perlapi - autogenerated documentation for the perl public API
This file contains most of the documentation of the perl public API, as generated by embed.pl. Specifically, it is a listing of functions, macros, flags, and variables that may be used by extension writers. Besides perlintern and config.h, some items are listed here as being actually documented in another pod.
At the end is a list of functions which have yet to be documented. Patches welcome! The interfaces of these are subject to change without notice.
Some of the functions documented here are consolidated so that a single entry serves for multiple functions which all do basically the same thing, but have some slight differences. For example, one form might process magic, while another doesn't. The name of each variation is listed at the top of the single entry. But if all have the same signature (arguments and return type) except for their names, only the usage for the base form is shown. If any one of the forms has a different signature (such as returning const
or not) every function's signature is explicitly displayed.
Anything not listed here or in the other mentioned pods is not part of the public API, and should not be used by extension writers at all. For these reasons, blindly using functions listed in proto.h is to be avoided when writing extensions.
In Perl, unlike C, a string of characters may generally contain embedded NUL
characters. Sometimes in the documentation a Perl string is referred to as a "buffer" to distinguish it from a C string, but sometimes they are both just referred to as strings.
Note that all Perl API global variables must be referenced with the PL_
prefix. Again, those not listed here are not to be used by extension writers, and can be changed or removed without notice; same with macros. Some macros are provided for compatibility with the older, unadorned names, but this support may be disabled in a future release.
Perl was originally written to handle US-ASCII only (that is characters whose ordinal numbers are in the range 0 - 127). And documentation and comments may still use the term ASCII, when sometimes in fact the entire range from 0 - 255 is meant.
The non-ASCII characters below 256 can have various meanings, depending on various things. (See, most notably, perllocale.) But usually the whole range can be referred to as ISO-8859-1. Often, the term "Latin-1" (or "Latin1") is used as an equivalent for ISO-8859-1. But some people treat "Latin1" as referring just to the characters in the range 128 through 255, or sometimes from 160 through 255. This documentation uses "Latin1" and "Latin-1" to refer to all 256 characters.
Note that Perl can be compiled and run under either ASCII or EBCDIC (See perlebcdic). Most of the documentation (and even comments in the code) ignore the EBCDIC possibility. For almost all purposes the differences are transparent. As an example, under EBCDIC, instead of UTF-8, UTF-EBCDIC is used to encode Unicode strings, and so whenever this documentation refers to utf8
(and variants of that name, including in function names), it also (essentially transparently) means UTF-EBCDIC
. But the ordinals of characters differ between ASCII, EBCDIC, and the UTF- encodings, and a string encoded in UTF-EBCDIC may occupy a different number of bytes than in UTF-8.
The organization of this document is tentative and subject to change. Suggestions and patches welcome perl5-porters@perl.org.
The sections in this document currently are
The listing below is alphabetical, case insensitive.
AV
Described in perlguts.
AvALLOC
Described in perlguts.
AvALLOC(AV* av)
AvARRAY
Returns a pointer to the AV's internal SV* array.
This is useful for doing pointer arithmetic on the array. If all you need is to look up an array element, then prefer av_fetch
.
SV** AvARRAY(AV* av)
av_clear
Frees all the elements of an array, leaving it empty. The XS equivalent of @array = ()
. See also "av_undef".
Note that it is possible that the actions of a destructor called directly or indirectly by freeing an element of the array could cause the reference count of the array itself to be reduced (e.g. by deleting an entry in the symbol table). So it is a possibility that the AV could have been freed (or even reallocated) on return from the call unless you hold a reference to it.
void av_clear(AV *av)
av_count
Returns the number of elements in the array av
. This is the true length of the array, including any undefined elements. It is always the same as
.av_top_index(av) + 1
Size_t av_count(AV *av)
av_create_and_push
Push an SV onto the end of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.
NOTE: av_create_and_push
must be explicitly called as Perl_av_create_and_push
with an aTHX_
parameter.
void Perl_av_create_and_push(pTHX_ AV **const avp, SV *const val)
av_create_and_unshift_one
Unshifts an SV onto the beginning of the array, creating the array if necessary. A small internal helper function to remove a commonly duplicated idiom.
NOTE: av_create_and_unshift_one
must be explicitly called as Perl_av_create_and_unshift_one
with an aTHX_
parameter.
SV** Perl_av_create_and_unshift_one(pTHX_ AV **const avp, SV *const val)
av_delete
Deletes the element indexed by key
from the array, makes the element mortal, and returns it. If flags
equals G_DISCARD
, the element is freed and NULL is returned. NULL is also returned if key
is out of range.
Perl equivalent:
(with the splice(@myarray, $key, 1, undef)
splice
in void context if G_DISCARD
is present).
SV* av_delete(AV *av, SSize_t key, I32 flags)
av_exists
Returns true if the element indexed by key
has been initialized.
This relies on the fact that uninitialized array elements are set to NULL
.
Perl equivalent: exists($myarray[$key])
.
bool av_exists(AV *av, SSize_t key)
av_extend
Pre-extend an array so that it is capable of storing values at indexes 0..key
. Thus av_extend(av,99)
guarantees that the array can store 100 elements, i.e. that av_store(av, 0, sv)
through av_store(av, 99, sv)
on a plain array will work without any further memory allocation.
If the av argument is a tied array then will call the EXTEND
tied array method with an argument of (key+1)
.
void av_extend(AV *av, SSize_t key)
av_fetch
Returns the SV at the specified index in the array. The key
is the index. If lval
is true, you are guaranteed to get a real SV back (in case it wasn't real before), which you can then modify. Check that the return value is non-NULL before dereferencing it to a SV*
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
The rough perl equivalent is $myarray[$key]
.
SV** av_fetch(AV *av, SSize_t key, I32 lval)
AvFILL
Same as "av_top_index"
or "av_tindex"
.
SSize_t AvFILL(AV* av)
av_fill
Set the highest index in the array to the given number, equivalent to Perl's
.$#array = $fill;
The number of elements in the array will be
after fill + 1
av_fill()
returns. If the array was previously shorter, then the additional elements appended are set to NULL. If the array was longer, then the excess elements are freed.
is the same as av_fill(av, -1)
av_clear(av)
.
void av_fill(AV *av, SSize_t fill)
av_len
Same as "av_top_index". Note that, unlike what the name implies, it returns the maximum index in the array. This is unlike "sv_len", which returns what you would expect.
To get the true number of elements in the array, instead use "av_count"
.
SSize_t av_len(AV *av)
av_make
Creates a new AV and populates it with a list (**strp
, length size
) of SVs. A copy is made of each SV, so their refcounts are not changed. The new AV will have a reference count of 1.
Perl equivalent: my @new_array = ($scalar1, $scalar2, $scalar3...);
AV* av_make(SSize_t size, SV **strp)
av_pop
Removes one SV from the end of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns &PL_sv_undef
if the array is empty.
Perl equivalent: pop(@myarray);
SV* av_pop(AV *av)
av_push
Pushes an SV (transferring control of one reference count) onto the end of the array. The array will grow automatically to accommodate the addition.
Perl equivalent: push @myarray, $val;
.
void av_push(AV *av, SV *val)
av_shift
Removes one SV from the start of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns &PL_sv_undef
if the array is empty.
Perl equivalent: shift(@myarray);
SV* av_shift(AV *av)
av_store
Stores an SV in an array. The array index is specified as key
. The return value will be NULL
if the operation failed or if the value did not need to be actually stored within the array (as in the case of tied arrays). Otherwise, it can be dereferenced to get the SV*
that was stored there (= val
)).
Note that the caller is responsible for suitably incrementing the reference count of val
before the call, and decrementing it if the function returned NULL
.
Approximate Perl equivalent: splice(@myarray, $key, 1, $val)
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
SV** av_store(AV *av, SSize_t key, SV *val)
av_tindex
av_top_index
These behave identically. If the array av
is empty, these return -1; otherwise they return the maximum value of the indices of all the array elements which are currently defined in av
.
They process 'get' magic.
The Perl equivalent for these is $#av
.
Use "av_count"
to get the number of elements in an array.
SSize_t av_tindex(AV *av)
av_undef
Undefines the array. The XS equivalent of undef(@array)
.
As well as freeing all the elements of the array (like av_clear()
), this also frees the memory used by the av to store its list of scalars.
See "av_clear" for a note about the array possibly being invalid on return.
void av_undef(AV *av)
av_unshift
Unshift the given number of undef
values onto the beginning of the array. The array will grow automatically to accommodate the addition.
Perl equivalent: unshift @myarray, ((undef) x $num);
void av_unshift(AV *av, SSize_t num)
get_av
Returns the AV of the specified Perl global or package array with the given name (so it won't work on lexical variables). flags
are passed to gv_fetchpv
. If GV_ADD
is set and the Perl variable does not exist then it will be created. If flags
is zero and the variable does not exist then NULL is returned.
Perl equivalent: @{"$name"}
.
NOTE: the perl_get_av()
form is deprecated.
AV* get_av(const char *name, I32 flags)
newAV
newAV_alloc_x
newAV_alloc_xz
These all create a new AV, setting the reference count to 1. If you also know the initial elements of the array with, see "av_make
".
As background, an array consists of three things:
An empty array need only have the first data structure, and all these functions create that. They differ in what else they do, as follows:
newAV
form
This does nothing beyond creating the whole-array data structure. The Perl equivalent is approximately my @array;
This is useful when the minimum size of the array could be zero (perhaps there are likely code paths that will entirely skip using it).
If the array does get used, the pointers data structure will need to be allocated at that time. This will end up being done by "av_extend">, either explicitly:
av_extend(av, len);
or implicitly when the first element is stored:
(void)av_store(av, 0, sv);
Unused array elements are typically initialized by av_extend
.
newAV_alloc_x
form
This effectively does a newAV
followed by also allocating (uninitialized) space for the pointers array. This is used when you know ahead of time the likely minimum size of the array. It is more efficient to do this than doing a plain newAV
followed by an av_extend
.
Of course the array can be extended later should it become necessary.
size
must be at least 1.
newAV_alloc_xz
form
This is newAV_alloc_x
, but initializes each pointer in it to NULL. This gives added safety to guard against them being read before being set.
size
must be at least 1.
The following examples all result in an array that can fit four elements (indexes 0 .. 3):
AV *av = newAV(); av_extend(av, 3); AV *av = newAV_alloc_x(4); AV *av = newAV_alloc_xz(4);
In contrast, the following examples allocate an array that is only guaranteed to fit one element without extending:
AV *av = newAV_alloc_x(1); AV *av = newAV_alloc_xz(1);
AV* newAV () AV* newAV_alloc_x (SSize_t size) AV* newAV_alloc_xz(SSize_t size)
call_argv
Performs a callback to the specified named and package-scoped Perl subroutine with argv
(a NULL
-terminated array of strings) as arguments. See perlcall.
Approximate Perl equivalent: &{"$sub_name"}(@$argv)
.
NOTE: the perl_call_argv()
form is deprecated.
I32 call_argv(const char* sub_name, I32 flags, char** argv)
call_method
Performs a callback to the specified Perl method. The blessed object must be on the stack. See perlcall.
NOTE: the perl_call_method()
form is deprecated.
I32 call_method(const char* methname, I32 flags)
call_pv
Performs a callback to the specified Perl sub. See perlcall.
NOTE: the perl_call_pv()
form is deprecated.
I32 call_pv(const char* sub_name, I32 flags)
call_sv
Performs a callback to the Perl sub specified by the SV.
If neither the G_METHOD
nor G_METHOD_NAMED
flag is supplied, the SV may be any of a CV, a GV, a reference to a CV, a reference to a GV or SvPV(sv)
will be used as the name of the sub to call.
If the G_METHOD
flag is supplied, the SV may be a reference to a CV or SvPV(sv)
will be used as the name of the method to call.
If the G_METHOD_NAMED
flag is supplied, SvPV(sv)
will be used as the name of the method to call.
Some other values are treated specially for internal use and should not be depended on.
See perlcall.
NOTE: the perl_call_sv()
form is deprecated.
I32 call_sv(SV* sv, volatile I32 flags)
DESTRUCTORFUNC_NOCONTEXT_t
Described in perlguts.
DESTRUCTORFUNC_t
Described in perlguts.
ENTER_with_name
Same as "ENTER"
, but when debugging is enabled it also associates the given literal string with the new scope.
ENTER_with_name("name");
eval_pv
Tells Perl to eval
the given string in scalar context and return an SV* result.
NOTE: the perl_eval_pv()
form is deprecated.
SV* eval_pv(const char* p, I32 croak_on_error)
eval_sv
Tells Perl to eval
the string in the SV. It supports the same flags as call_sv
, with the obvious exception of G_EVAL
. See perlcall.
The G_RETHROW
flag can be used if you only need eval_sv() to execute code specified by a string, but not catch any errors.
NOTE: the perl_eval_sv()
form is deprecated.
I32 eval_sv(SV* sv, I32 flags)
FREETMPS
Closing bracket for temporaries on a callback. See "SAVETMPS"
and perlcall.
FREETMPS;
G_DISCARD
Described in perlcall.
G_EVAL
Described in perlcall.
GIMME
DEPRECATED!
It is planned to remove GIMME
from a future release of Perl. Do not use it for new code; remove it from existing code.
A backward-compatible version of GIMME_V
which can only return G_SCALAR
or G_LIST
; in a void context, it returns G_SCALAR
. Deprecated. Use GIMME_V
instead.
U32 GIMME
GIMME_V
The XSUB-writer's equivalent to Perl's wantarray
. Returns G_VOID
, G_SCALAR
or G_LIST
for void, scalar or list context, respectively. See perlcall for a usage example.
U32 GIMME_V
G_KEEPERR
Described in perlcall.
G_LIST
Described in perlcall.
G_NOARGS
Described in perlcall.
G_SCALAR
Described in perlcall.
G_VOID
Described in perlcall.
is_lvalue_sub
Returns non-zero if the sub calling this function is being called in an lvalue context. Returns 0 otherwise.
I32 is_lvalue_sub()
LEAVE_with_name
Same as "LEAVE"
, but when debugging is enabled it first checks that the scope has the given name. name
must be a literal string.
LEAVE_with_name("name");
PL_errgv
Described in perlcall.
save_aptr
Described in perlguts.
void save_aptr(AV** aptr)
save_ary
Described in perlguts.
AV* save_ary(GV* gv)
SAVEBOOL
Described in perlguts.
SAVEBOOL(bool i)
SAVEDELETE
Described in perlguts.
SAVEDELETE(HV * hv, char * key, I32 length)
SAVEDESTRUCTOR
Described in perlguts.
SAVEDESTRUCTOR(DESTRUCTORFUNC_NOCONTEXT_t f, void *p)
SAVEDESTRUCTOR_X
Described in perlguts.
SAVEDESTRUCTOR_X(DESTRUCTORFUNC_t f, void *p)
SAVEFREEOP
Described in perlguts.
SAVEFREEOP(OP *op)
SAVEFREEPV
Described in perlguts.
SAVEFREEPV(void * p)
SAVEFREESV
Described in perlguts.
SAVEFREESV(SV* sv)
save_hash
Described in perlguts.
HV* save_hash(GV* gv)
save_hptr
Described in perlguts.
void save_hptr(HV** hptr)
SAVEI8
Described in perlguts.
SAVEI8(I8 i)
SAVEI32
Described in perlguts.
SAVEI32(I32 i)
SAVEI16
Described in perlguts.
SAVEI16(I16 i)
SAVEINT
Described in perlguts.
SAVEINT(int i)
save_item
Described in perlguts.
void save_item(SV* item)
SAVEIV
Described in perlguts.
SAVEIV(IV i)
save_list
DEPRECATED!
It is planned to remove save_list
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlguts.
void save_list(SV** sarg, I32 maxsarg)
SAVELONG
Described in perlguts.
SAVELONG(long i)
SAVEMORTALIZESV
Described in perlguts.
SAVEMORTALIZESV(SV* sv)
SAVEPPTR
Described in perlguts.
SAVEPPTR(char * p)
save_scalar
Described in perlguts.
SV* save_scalar(GV* gv)
SAVESPTR
Described in perlguts.
SAVESPTR(SV * s)
SAVESTACK_POS
Described in perlguts.
SAVESTACK_POS()
SAVESTRLEN
Described in perlguts.
SAVESTRLEN(STRLEN i)
save_svref
Described in perlguts.
SV* save_svref(SV** sptr)
SAVETMPS
Opening bracket for temporaries on a callback. See "FREETMPS"
and perlcall.
SAVETMPS;
cBOOL
Cast-to-bool. When Perl was able to be compiled on pre-C99 compilers, a (bool)
cast didn't necessarily do the right thing, so this macro was created (and made somewhat complicated to work around bugs in old compilers). Now, many years later, and C99 is used, this is no longer required, but is kept for backwards compatibility.
bool cBOOL(bool expr)
INT2PTR
Described in perlguts.
type INT2PTR(type, int value)
PTR2IV
Described in perlguts.
IV PTR2IV(void * ptr)
PTR2nat
Described in perlguts.
IV PTR2nat(void *)
PTR2NV
Described in perlguts.
NV PTR2NV(void * ptr)
PTR2ul
Described in perlguts.
unsigned long PTR2ul(void *)
PTR2UV
Described in perlguts.
UV PTR2UV(void * ptr)
PTRV
Described in perlguts.
Perl uses "full" Unicode case mappings. This means that converting a single character to another case may result in a sequence of more than one character. For example, the uppercase of ß
(LATIN SMALL LETTER SHARP S) is the two character sequence SS
. This presents some complications The lowercase of all characters in the range 0..255 is a single character, and thus "toLOWER_L1"
is furnished. But, toUPPER_L1
can't exist, as it couldn't return a valid result for all legal inputs. Instead "toUPPER_uvchr"
has an API that does allow every possible legal result to be returned.) Likewise no other function that is crippled by not being able to give the correct results for the full range of possible inputs has been implemented here.
toFOLD
toFOLD_A
toFOLD_uvchr
toFOLD_utf8
toFOLD_utf8_safe
These all return the foldcase of a character. "foldcase" is an internal case for /i
pattern matching. If the foldcase of character A and the foldcase of character B are the same, they match caselessly; otherwise they don't.
The differences in the forms are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments
.p .. e - 1
toFOLD
and toFOLD_A
are synonyms of each other. They return the foldcase of any ASCII-range code point. In this range, the foldcase is identical to the lowercase. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is no toFOLD_L1
nor toFOLD_LATIN1
as the foldcase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead use toFOLD_uvchr
.
toFOLD_uvchr
returns the foldcase of any Unicode code point. The return value is identical to that of toFOLD_A
for input code points in the ASCII range. The foldcase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the foldcase of a code point may be more than one code point. The return value of this function is only the first of these. The entire foldcase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toFOLD_uvchr(cp, s, &len); if (len > UTF8SKIP(s)) { is multiple code points } else { is a single code point }
toFOLD_utf8
and toFOLD_utf8_safe
are synonyms of each other. The only difference between these and toFOLD_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.e - 1
UV toFOLD (UV cp) UV toFOLD_A (UV cp) UV toFOLD_uvchr (UV cp, U8* s, STRLEN* lenp) UV toFOLD_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp) UV toFOLD_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
toLOWER
toLOWER_A
toLOWER_L1
toLOWER_LATIN1
toLOWER_LC
toLOWER_uvchr
toLOWER_utf8
toLOWER_utf8_safe
These all return the lowercase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments
.p .. e - 1
toLOWER
and toLOWER_A
are synonyms of each other. They return the lowercase of any uppercase ASCII-range code point. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
toLOWER_L1
and toLOWER_LATIN1
are synonyms of each other. They behave identically as toLOWER
for ASCII-range input. But additionally will return the lowercase of any uppercase code point in the entire 0..255 range, assuming a Latin-1 encoding (or the EBCDIC equivalent on such platforms).
toLOWER_LC
returns the lowercase of the input code point according to the rules of the current POSIX locale. Input code points outside the range 0..255 are returned unchanged.
toLOWER_uvchr
returns the lowercase of any Unicode code point. The return value is identical to that of toLOWER_L1
for input code points in the 0..255 range. The lowercase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the lowercase of a code point may be more than one code point. The return value of this function is only the first of these. The entire lowercase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toLOWER_uvchr(cp, s, &len); if (len > UTF8SKIP(s)) { is multiple code points } else { is a single code point }
toLOWER_utf8
and toLOWER_utf8_safe
are synonyms of each other. The only difference between these and toLOWER_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.e - 1
UV toLOWER (UV cp) UV toLOWER_A (UV cp) UV toLOWER_L1 (UV cp) UV toLOWER_LATIN1 (UV cp) UV toLOWER_LC (UV cp) UV toLOWER_uvchr (UV cp, U8* s, STRLEN* lenp) UV toLOWER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp) UV toLOWER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
toTITLE
toTITLE_A
toTITLE_uvchr
toTITLE_utf8
toTITLE_utf8_safe
These all return the titlecase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments
.p .. e - 1
toTITLE
and toTITLE_A
are synonyms of each other. They return the titlecase of any lowercase ASCII-range code point. In this range, the titlecase is identical to the uppercase. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is no toTITLE_L1
nor toTITLE_LATIN1
as the titlecase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead use toTITLE_uvchr
.
toTITLE_uvchr
returns the titlecase of any Unicode code point. The return value is identical to that of toTITLE_A
for input code points in the ASCII range. The titlecase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the titlecase of a code point may be more than one code point. The return value of this function is only the first of these. The entire titlecase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toTITLE_uvchr(cp, s, &len); if (len > UTF8SKIP(s)) { is multiple code points } else { is a single code point }
toTITLE_utf8
and toTITLE_utf8_safe
are synonyms of each other. The only difference between these and toTITLE_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.e - 1
UV toTITLE (UV cp) UV toTITLE_A (UV cp) UV toTITLE_uvchr (UV cp, U8* s, STRLEN* lenp) UV toTITLE_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp) UV toTITLE_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
toUPPER
toUPPER_A
toUPPER_uvchr
toUPPER_utf8
toUPPER_utf8_safe
These all return the uppercase of a character. The differences are what domain they operate on, and whether the input is specified as a code point (those forms with a cp
parameter) or as a UTF-8 string (the others). In the latter case, the code point to use is the first one in the buffer of UTF-8 encoded code points, delineated by the arguments
.p .. e - 1
toUPPER
and toUPPER_A
are synonyms of each other. They return the uppercase of any lowercase ASCII-range code point. All other inputs are returned unchanged. Since these are macros, the input type may be any integral one, and the output will occupy the same number of bits as the input.
There is no toUPPER_L1
nor toUPPER_LATIN1
as the uppercase of some code points in the 0..255 range is above that range or consists of multiple characters. Instead use toUPPER_uvchr
.
toUPPER_uvchr
returns the uppercase of any Unicode code point. The return value is identical to that of toUPPER_A
for input code points in the ASCII range. The uppercase of the vast majority of Unicode code points is the same as the code point itself. For these, and for code points above the legal Unicode maximum, this returns the input code point unchanged. It additionally stores the UTF-8 of the result into the buffer beginning at s
, and its length in bytes into *lenp
. The caller must have made s
large enough to contain at least UTF8_MAXBYTES_CASE+1
bytes to avoid possible overflow.
NOTE: the uppercase of a code point may be more than one code point. The return value of this function is only the first of these. The entire uppercase is returned in s
. To determine if the result is more than a single code point, you can do something like this:
uc = toUPPER_uvchr(cp, s, &len); if (len > UTF8SKIP(s)) { is multiple code points } else { is a single code point }
toUPPER_utf8
and toUPPER_utf8_safe
are synonyms of each other. The only difference between these and toUPPER_uvchr
is that the source for these is encoded in UTF-8, instead of being a code point. It is passed as a buffer starting at p
, with e
pointing to one byte beyond its end. The p
buffer may certainly contain more than one code point; but only the first one (up through
) is examined. If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.e - 1
UV toUPPER (UV cp) UV toUPPER_A (UV cp) UV toUPPER_uvchr (UV cp, U8* s, STRLEN* lenp) UV toUPPER_utf8 (U8* p, U8* e, U8* s, STRLEN* lenp) UV toUPPER_utf8_safe(U8* p, U8* e, U8* s, STRLEN* lenp)
This section is about functions (really macros) that classify characters into types, such as punctuation versus alphabetic, etc. Most of these are analogous to regular expression character classes. (See "POSIX Character Classes" in perlrecharclass.) There are several variants for each class. (Not all macros have all variants; each item below lists the ones valid for it.) None are affected by use bytes
, and only the ones with LC
in the name are affected by the current locale.
The base function, e.g., isALPHA()
, takes any signed or unsigned value, treating it as a code point, and returns a boolean as to whether or not the character represented by it is (or on non-ASCII platforms, corresponds to) an ASCII character in the named class based on platform, Unicode, and Perl rules. If the input is a number that doesn't fit in an octet, FALSE is returned.
Variant isFOO_A
(e.g., isALPHA_A()
) is identical to the base function with no suffix "_A"
. This variant is used to emphasize by its name that only ASCII-range characters can return TRUE.
Variant isFOO_L1
imposes the Latin-1 (or EBCDIC equivalent) character set onto the platform. That is, the code points that are ASCII are unaffected, since ASCII is a subset of Latin-1. But the non-ASCII code points are treated as if they are Latin-1 characters. For example, isWORDCHAR_L1()
will return true when called with the code point 0xDF, which is a word character in both ASCII and EBCDIC (though it represents different characters in each). If the input is a number that doesn't fit in an octet, FALSE is returned. (Perl's documentation uses a colloquial definition of Latin-1, to include all code points below 256.)
Variant isFOO_uvchr
is exactly like the isFOO_L1
variant, for inputs below 256, but if the code point is larger than 255, Unicode rules are used to determine if it is in the character class. For example, isWORDCHAR_uvchr(0x100)
returns TRUE, since 0x100 is LATIN CAPITAL LETTER A WITH MACRON in Unicode, and is a word character.
Variants isFOO_utf8
and isFOO_utf8_safe
are like isFOO_uvchr
, but are used for UTF-8 encoded strings. The two forms are different names for the same thing. Each call to one of these classifies the first character of the string starting at p
. The second parameter, e
, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. Although both variants are identical, the suffix _safe
in one name emphasizes that it will not attempt to read beyond
, provided that the constraint e - 1
is true (this is asserted for in s < e
-DDEBUGGING
builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
Variant isFOO_LC
is like the isFOO_A
and isFOO_L1
variants, but the result is based on the current locale, which is what LC
in the name stands for. If Perl can determine that the current locale is a UTF-8 locale, it uses the published Unicode rules; otherwise, it uses the C library function that gives the named classification. For example, isDIGIT_LC()
when not in a UTF-8 locale returns the result of calling isdigit()
. FALSE is always returned if the input won't fit into an octet. On some platforms where the C library function is known to be defective, Perl changes its result to follow the POSIX standard's rules.
Variant isFOO_LC_uvchr
acts exactly like isFOO_LC
for inputs less than 256, but for larger ones it returns the Unicode classification of the code point.
Variants isFOO_LC_utf8
and isFOO_LC_utf8_safe
are like isFOO_LC_uvchr
, but are used for UTF-8 encoded strings. The two forms are different names for the same thing. Each call to one of these classifies the first character of the string starting at p
. The second parameter, e
, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. Although both variants are identical, the suffix _safe
in one name emphasizes that it will not attempt to read beyond
, provided that the constraint e - 1
is true (this is asserted for in s < e
-DDEBUGGING
builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
isALPHA
isALPHA_A
isALPHA_L1
isALPHA_uvchr
isALPHA_utf8_safe
isALPHA_utf8
isALPHA_LC
isALPHA_LC_uvchr
isALPHA_LC_utf8_safe
Returns a boolean indicating whether the specified input is one of [A-Za-z]
, analogous to m/[[:alpha:]]/
. See the top of this section for an explanation of the variants.
bool isALPHA (UV ch) bool isALPHA_A (UV ch) bool isALPHA_L1 (UV ch) bool isALPHA_uvchr (UV ch) bool isALPHA_utf8_safe (U8 * s, U8 * end) bool isALPHA_utf8 (U8 * s, U8 * end) bool isALPHA_LC (UV ch) bool isALPHA_LC_uvchr (UV ch) bool isALPHA_LC_utf8_safe(U8 * s, U8 *end)
isALPHANUMERIC
isALPHANUMERIC_A
isALPHANUMERIC_L1
isALPHANUMERIC_uvchr
isALPHANUMERIC_utf8_safe
isALPHANUMERIC_utf8
isALPHANUMERIC_LC
isALPHANUMERIC_LC_uvchr
isALPHANUMERIC_LC_utf8_safe
isALNUMC
isALNUMC_A
isALNUMC_L1
isALNUMC_LC
isALNUMC_LC_uvchr
Returns a boolean indicating whether the specified character is one of [A-Za-z0-9]
, analogous to m/[[:alnum:]]/
. See the top of this section for an explanation of the variants.
A (discouraged from use) synonym is isALNUMC
(where the C
suffix means this corresponds to the C language alphanumeric definition). Also there are the variants isALNUMC_A
, isALNUMC_L1
isALNUMC_LC
, and isALNUMC_LC_uvchr
.
bool isALPHANUMERIC (UV ch) bool isALPHANUMERIC_A (UV ch) bool isALPHANUMERIC_L1 (UV ch) bool isALPHANUMERIC_uvchr (UV ch) bool isALPHANUMERIC_utf8_safe (U8 * s, U8 * end) bool isALPHANUMERIC_utf8 (U8 * s, U8 * end) bool isALPHANUMERIC_LC (UV ch) bool isALPHANUMERIC_LC_uvchr (UV ch) bool isALPHANUMERIC_LC_utf8_safe(U8 * s, U8 *end) bool isALNUMC (UV ch) bool isALNUMC_A (UV ch) bool isALNUMC_L1 (UV ch) bool isALNUMC_LC (UV ch) bool isALNUMC_LC_uvchr (UV ch)
isASCII
isASCII_A
isASCII_L1
isASCII_uvchr
isASCII_utf8_safe
isASCII_utf8
isASCII_LC
isASCII_LC_uvchr
isASCII_LC_utf8_safe
Returns a boolean indicating whether the specified character is one of the 128 characters in the ASCII character set, analogous to m/[[:ascii:]]/
. On non-ASCII platforms, it returns TRUE iff this character corresponds to an ASCII character. Variants isASCII_A()
and isASCII_L1()
are identical to isASCII()
. See the top of this section for an explanation of the variants. Note, however, that some platforms do not have the C library routine isascii()
. In these cases, the variants whose names contain LC
are the same as the corresponding ones without.
Also note, that because all ASCII characters are UTF-8 invariant (meaning they have the exact same representation (always a single byte) whether encoded in UTF-8 or not), isASCII
will give the correct results when called with any byte in any string encoded or not in UTF-8. And similarly isASCII_utf8
and isASCII_utf8_safe
will work properly on any string encoded or not in UTF-8.
bool isASCII (UV ch) bool isASCII_A (UV ch) bool isASCII_L1 (UV ch) bool isASCII_uvchr (UV ch) bool isASCII_utf8_safe (U8 * s, U8 * end) bool isASCII_utf8 (U8 * s, U8 * end) bool isASCII_LC (UV ch) bool isASCII_LC_uvchr (UV ch) bool isASCII_LC_utf8_safe(U8 * s, U8 *end)
isBLANK
isBLANK_A
isBLANK_L1
isBLANK_uvchr
isBLANK_utf8_safe
isBLANK_utf8
isBLANK_LC
isBLANK_LC_uvchr
isBLANK_LC_utf8_safe
Returns a boolean indicating whether the specified character is a character considered to be a blank, analogous to m/[[:blank:]]/
. See the top of this section for an explanation of the variants. Note, however, that some platforms do not have the C library routine isblank()
. In these cases, the variants whose names contain LC
are the same as the corresponding ones without.
bool isBLANK (UV ch) bool isBLANK_A (UV ch) bool isBLANK_L1 (UV ch) bool isBLANK_uvchr (UV ch) bool isBLANK_utf8_safe (U8 * s, U8 * end) bool isBLANK_utf8 (U8 * s, U8 * end) bool isBLANK_LC (UV ch) bool isBLANK_LC_uvchr (UV ch) bool isBLANK_LC_utf8_safe(U8 * s, U8 *end)
isCNTRL
isCNTRL_A
isCNTRL_L1
isCNTRL_uvchr
isCNTRL_utf8_safe
isCNTRL_utf8
isCNTRL_LC
isCNTRL_LC_uvchr
isCNTRL_LC_utf8_safe
Returns a boolean indicating whether the specified character is a control character, analogous to m/[[:cntrl:]]/
. See the top of this section for an explanation of the variants. On EBCDIC platforms, you almost always want to use the isCNTRL_L1
variant.
bool isCNTRL (UV ch) bool isCNTRL_A (UV ch) bool isCNTRL_L1 (UV ch) bool isCNTRL_uvchr (UV ch) bool isCNTRL_utf8_safe (U8 * s, U8 * end) bool isCNTRL_utf8 (U8 * s, U8 * end) bool isCNTRL_LC (UV ch) bool isCNTRL_LC_uvchr (UV ch) bool isCNTRL_LC_utf8_safe(U8 * s, U8 *end)
isDIGIT
isDIGIT_A
isDIGIT_L1
isDIGIT_uvchr
isDIGIT_utf8_safe
isDIGIT_utf8
isDIGIT_LC
isDIGIT_LC_uvchr
isDIGIT_LC_utf8_safe
Returns a boolean indicating whether the specified character is a digit, analogous to m/[[:digit:]]/
. Variants isDIGIT_A
and isDIGIT_L1
are identical to isDIGIT
. See the top of this section for an explanation of the variants.
bool isDIGIT (UV ch) bool isDIGIT_A (UV ch) bool isDIGIT_L1 (UV ch) bool isDIGIT_uvchr (UV ch) bool isDIGIT_utf8_safe (U8 * s, U8 * end) bool isDIGIT_utf8 (U8 * s, U8 * end) bool isDIGIT_LC (UV ch) bool isDIGIT_LC_uvchr (UV ch) bool isDIGIT_LC_utf8_safe(U8 * s, U8 *end)
isGRAPH
isGRAPH_A
isGRAPH_L1
isGRAPH_uvchr
isGRAPH_utf8_safe
isGRAPH_utf8
isGRAPH_LC
isGRAPH_LC_uvchr
isGRAPH_LC_utf8_safe
Returns a boolean indicating whether the specified character is a graphic character, analogous to m/[[:graph:]]/
. See the top of this section for an explanation of the variants.
bool isGRAPH (UV ch) bool isGRAPH_A (UV ch) bool isGRAPH_L1 (UV ch) bool isGRAPH_uvchr (UV ch) bool isGRAPH_utf8_safe (U8 * s, U8 * end) bool isGRAPH_utf8 (U8 * s, U8 * end) bool isGRAPH_LC (UV ch) bool isGRAPH_LC_uvchr (UV ch) bool isGRAPH_LC_utf8_safe(U8 * s, U8 *end)
isIDCONT
isIDCONT_A
isIDCONT_L1
isIDCONT_uvchr
isIDCONT_utf8_safe
isIDCONT_utf8
isIDCONT_LC
isIDCONT_LC_uvchr
isIDCONT_LC_utf8_safe
Returns a boolean indicating whether the specified character can be the second or succeeding character of an identifier. This is very close to, but not quite the same as the official Unicode property XID_Continue
. The difference is that this returns true only if the input character also matches "isWORDCHAR". See the top of this section for an explanation of the variants.
bool isIDCONT (UV ch) bool isIDCONT_A (UV ch) bool isIDCONT_L1 (UV ch) bool isIDCONT_uvchr (UV ch) bool isIDCONT_utf8_safe (U8 * s, U8 * end) bool isIDCONT_utf8 (U8 * s, U8 * end) bool isIDCONT_LC (UV ch) bool isIDCONT_LC_uvchr (UV ch) bool isIDCONT_LC_utf8_safe(U8 * s, U8 *end)
isIDFIRST
isIDFIRST_A
isIDFIRST_L1
isIDFIRST_uvchr
isIDFIRST_utf8_safe
isIDFIRST_utf8
isIDFIRST_LC
isIDFIRST_LC_uvchr
isIDFIRST_LC_utf8_safe
Returns a boolean indicating whether the specified character can be the first character of an identifier. This is very close to, but not quite the same as the official Unicode property XID_Start
. The difference is that this returns true only if the input character also matches "isWORDCHAR". See the top of this section for an explanation of the variants.
bool isIDFIRST (UV ch) bool isIDFIRST_A (UV ch) bool isIDFIRST_L1 (UV ch) bool isIDFIRST_uvchr (UV ch) bool isIDFIRST_utf8_safe (U8 * s, U8 * end) bool isIDFIRST_utf8 (U8 * s, U8 * end) bool isIDFIRST_LC (UV ch) bool isIDFIRST_LC_uvchr (UV ch) bool isIDFIRST_LC_utf8_safe(U8 * s, U8 *end)
isLOWER
isLOWER_A
isLOWER_L1
isLOWER_uvchr
isLOWER_utf8_safe
isLOWER_utf8
isLOWER_LC
isLOWER_LC_uvchr
isLOWER_LC_utf8_safe
Returns a boolean indicating whether the specified character is a lowercase character, analogous to m/[[:lower:]]/
. See the top of this section for an explanation of the variants
bool isLOWER (UV ch) bool isLOWER_A (UV ch) bool isLOWER_L1 (UV ch) bool isLOWER_uvchr (UV ch) bool isLOWER_utf8_safe (U8 * s, U8 * end) bool isLOWER_utf8 (U8 * s, U8 * end) bool isLOWER_LC (UV ch) bool isLOWER_LC_uvchr (UV ch) bool isLOWER_LC_utf8_safe(U8 * s, U8 *end)
isOCTAL
isOCTAL_A
isOCTAL_L1
Returns a boolean indicating whether the specified character is an octal digit, [0-7]. The only two variants are isOCTAL_A
and isOCTAL_L1
; each is identical to isOCTAL
.
bool isOCTAL(UV ch)
isPRINT
isPRINT_A
isPRINT_L1
isPRINT_uvchr
isPRINT_utf8_safe
isPRINT_utf8
isPRINT_LC
isPRINT_LC_uvchr
isPRINT_LC_utf8_safe
Returns a boolean indicating whether the specified character is a printable character, analogous to m/[[:print:]]/
. See the top of this section for an explanation of the variants.
bool isPRINT (UV ch) bool isPRINT_A (UV ch) bool isPRINT_L1 (UV ch) bool isPRINT_uvchr (UV ch) bool isPRINT_utf8_safe (U8 * s, U8 * end) bool isPRINT_utf8 (U8 * s, U8 * end) bool isPRINT_LC (UV ch) bool isPRINT_LC_uvchr (UV ch) bool isPRINT_LC_utf8_safe(U8 * s, U8 *end)
isPSXSPC
isPSXSPC_A
isPSXSPC_L1
isPSXSPC_uvchr
isPSXSPC_utf8_safe
isPSXSPC_utf8
isPSXSPC_LC
isPSXSPC_LC_uvchr
isPSXSPC_LC_utf8_safe
(short for Posix Space) Starting in 5.18, this is identical in all its forms to the corresponding isSPACE()
macros. The locale forms of this macro are identical to their corresponding isSPACE()
forms in all Perl releases. In releases prior to 5.18, the non-locale forms differ from their isSPACE()
forms only in that the isSPACE()
forms don't match a Vertical Tab, and the isPSXSPC()
forms do. Otherwise they are identical. Thus this macro is analogous to what m/[[:space:]]/
matches in a regular expression. See the top of this section for an explanation of the variants.
bool isPSXSPC (UV ch) bool isPSXSPC_A (UV ch) bool isPSXSPC_L1 (UV ch) bool isPSXSPC_uvchr (UV ch) bool isPSXSPC_utf8_safe (U8 * s, U8 * end) bool isPSXSPC_utf8 (U8 * s, U8 * end) bool isPSXSPC_LC (UV ch) bool isPSXSPC_LC_uvchr (UV ch) bool isPSXSPC_LC_utf8_safe(U8 * s, U8 *end)
isPUNCT
isPUNCT_A
isPUNCT_L1
isPUNCT_uvchr
isPUNCT_utf8_safe
isPUNCT_utf8
isPUNCT_LC
isPUNCT_LC_uvchr
isPUNCT_LC_utf8_safe
Returns a boolean indicating whether the specified character is a punctuation character, analogous to m/[[:punct:]]/
. Note that the definition of what is punctuation isn't as straightforward as one might desire. See "POSIX Character Classes" in perlrecharclass for details. See the top of this section for an explanation of the variants.
bool isPUNCT (UV ch) bool isPUNCT_A (UV ch) bool isPUNCT_L1 (UV ch) bool isPUNCT_uvchr (UV ch) bool isPUNCT_utf8_safe (U8 * s, U8 * end) bool isPUNCT_utf8 (U8 * s, U8 * end) bool isPUNCT_LC (UV ch) bool isPUNCT_LC_uvchr (UV ch) bool isPUNCT_LC_utf8_safe(U8 * s, U8 *end)
isSPACE
isSPACE_A
isSPACE_L1
isSPACE_uvchr
isSPACE_utf8_safe
isSPACE_utf8
isSPACE_LC
isSPACE_LC_uvchr
isSPACE_LC_utf8_safe
Returns a boolean indicating whether the specified character is a whitespace character. This is analogous to what m/\s/
matches in a regular expression. Starting in Perl 5.18 this also matches what m/[[:space:]]/
does. Prior to 5.18, only the locale forms of this macro (the ones with LC
in their names) matched precisely what m/[[:space:]]/
does. In those releases, the only difference, in the non-locale variants, was that isSPACE()
did not match a vertical tab. (See "isPSXSPC" for a macro that matches a vertical tab in all releases.) See the top of this section for an explanation of the variants.
bool isSPACE (UV ch) bool isSPACE_A (UV ch) bool isSPACE_L1 (UV ch) bool isSPACE_uvchr (UV ch) bool isSPACE_utf8_safe (U8 * s, U8 * end) bool isSPACE_utf8 (U8 * s, U8 * end) bool isSPACE_LC (UV ch) bool isSPACE_LC_uvchr (UV ch) bool isSPACE_LC_utf8_safe(U8 * s, U8 *end)
isUPPER
isUPPER_A
isUPPER_L1
isUPPER_uvchr
isUPPER_utf8_safe
isUPPER_utf8
isUPPER_LC
isUPPER_LC_uvchr
isUPPER_LC_utf8_safe
Returns a boolean indicating whether the specified character is an uppercase character, analogous to m/[[:upper:]]/
. See the top of this section for an explanation of the variants.
bool isUPPER (UV ch) bool isUPPER_A (UV ch) bool isUPPER_L1 (UV ch) bool isUPPER_uvchr (UV ch) bool isUPPER_utf8_safe (U8 * s, U8 * end) bool isUPPER_utf8 (U8 * s, U8 * end) bool isUPPER_LC (UV ch) bool isUPPER_LC_uvchr (UV ch) bool isUPPER_LC_utf8_safe(U8 * s, U8 *end)
isWORDCHAR
isWORDCHAR_A
isWORDCHAR_L1
isWORDCHAR_uvchr
isWORDCHAR_utf8_safe
isWORDCHAR_utf8
isWORDCHAR_LC
isWORDCHAR_LC_uvchr
isWORDCHAR_LC_utf8_safe
isALNUM
isALNUM_A
isALNUM_LC
isALNUM_LC_uvchr
Returns a boolean indicating whether the specified character is a character that is a word character, analogous to what m/\w/
and m/[[:word:]]/
match in a regular expression. A word character is an alphabetic character, a decimal digit, a connecting punctuation character (such as an underscore), or a "mark" character that attaches to one of those (like some sort of accent). isALNUM()
is a synonym provided for backward compatibility, even though a word character includes more than the standard C language meaning of alphanumeric. See the top of this section for an explanation of the variants. isWORDCHAR_A
, isWORDCHAR_L1
, isWORDCHAR_uvchr
, isWORDCHAR_LC
, isWORDCHAR_LC_uvchr
, isWORDCHAR_LC_utf8
, and isWORDCHAR_LC_utf8_safe
are also as described there, but additionally include the platform's native underscore.
bool isWORDCHAR (UV ch) bool isWORDCHAR_A (UV ch) bool isWORDCHAR_L1 (UV ch) bool isWORDCHAR_uvchr (UV ch) bool isWORDCHAR_utf8_safe (U8 * s, U8 * end) bool isWORDCHAR_utf8 (U8 * s, U8 * end) bool isWORDCHAR_LC (UV ch) bool isWORDCHAR_LC_uvchr (UV ch) bool isWORDCHAR_LC_utf8_safe(U8 * s, U8 *end) bool isALNUM (UV ch) bool isALNUM_A (UV ch) bool isALNUM_LC (UV ch) bool isALNUM_LC_uvchr (UV ch)
isXDIGIT
isXDIGIT_A
isXDIGIT_L1
isXDIGIT_uvchr
isXDIGIT_utf8_safe
isXDIGIT_utf8
isXDIGIT_LC
isXDIGIT_LC_uvchr
isXDIGIT_LC_utf8_safe
Returns a boolean indicating whether the specified character is a hexadecimal digit. In the ASCII range these are [0-9A-Fa-f]
. Variants isXDIGIT_A()
and isXDIGIT_L1()
are identical to isXDIGIT()
. See the top of this section for an explanation of the variants.
bool isXDIGIT (UV ch) bool isXDIGIT_A (UV ch) bool isXDIGIT_L1 (UV ch) bool isXDIGIT_uvchr (UV ch) bool isXDIGIT_utf8_safe (U8 * s, U8 * end) bool isXDIGIT_utf8 (U8 * s, U8 * end) bool isXDIGIT_LC (UV ch) bool isXDIGIT_LC_uvchr (UV ch) bool isXDIGIT_LC_utf8_safe(U8 * s, U8 *end)
CPPLAST
This symbol is intended to be used along with CPPRUN
in the same manner symbol CPPMINUS
is used with CPPSTDIN
. It contains either "-" or "".
CPPMINUS
This symbol contains the second part of the string which will invoke the C preprocessor on the standard input and produce to standard output. This symbol will have the value "-" if CPPSTDIN
needs a minus to specify standard input, otherwise the value is "".
CPPRUN
This symbol contains the string which will invoke a C preprocessor on the standard input and produce to standard output. It needs to end with CPPLAST
, after all other preprocessor flags have been specified. The main difference with CPPSTDIN
is that this program will never be a pointer to a shell wrapper, i.e. it will be empty if no preprocessor is available directly to the user. Note that it may well be different from the preprocessor used to compile the C program.
CPPSTDIN
This symbol contains the first part of the string which will invoke the C preprocessor on the standard input and produce to standard output. Typical value of "cc -E" or "/lib/cpp", but it can also call a wrapper. See "CPPRUN"
.
HAS_BUILTIN_ADD_OVERFLOW
This symbol, if defined, indicates that the compiler supports __builtin_add_overflow
for adding integers with overflow checks.
HAS_BUILTIN_MUL_OVERFLOW
This symbol, if defined, indicates that the compiler supports __builtin_mul_overflow
for multiplying integers with overflow checks.
HAS_BUILTIN_SUB_OVERFLOW
This symbol, if defined, indicates that the compiler supports __builtin_sub_overflow
for subtracting integers with overflow checks.
HAS_STATIC_INLINE
This symbol, if defined, indicates that the C compiler supports C99-style static inline. That is, the function can't be called from another translation unit.
MEM_ALIGNBYTES
This symbol contains the number of bytes required to align a double, or a long double when applicable. Usual values are 2, 4 and 8. The default is eight, for safety. For cross-compiling or multiarch support, Configure will set a minimum of 8.
PERL_STATIC_INLINE
This symbol gives the best-guess incantation to use for static inline functions. If HAS_STATIC_INLINE
is defined, this will give C99-style inline. If HAS_STATIC_INLINE
is not defined, this will give a plain 'static'. It will always be defined to something that gives static linkage. Possibilities include
static inline (c99) static __inline__ (gcc -ansi) static __inline (MSVC) static _inline (older MSVC) static (c89 compilers)
PERL_THREAD_LOCAL
This symbol, if defined, gives a linkage specification for thread-local storage. For example, for a C11 compiler this will be _Thread_local
. Beware, some compilers are sensitive to the C language standard they are told to parse. For example, suncc defaults to C11, so our probe will report that _Thread_local
can be used. However, if the -std=c99 is later added to the compiler flags, then _Thread_local
will become a syntax error. Hence it is important for these flags to be consistent between probing and use.
ASSUME
ASSUME
is like assert()
, but it has a benefit in a release build. It is a hint to a compiler about a statement of fact in a function call free expression, which allows the compiler to generate better machine code. In a debug build, ASSUME(x)
is a synonym for assert(x)
. ASSUME(0)
means the control path is unreachable. In a for loop, ASSUME
can be used to hint that a loop will run at least X times. ASSUME
is based off MSVC's __assume
intrinsic function, see its documents for more details.
ASSUME(bool expr)
dNOOP
Declare nothing; typically used as a placeholder to replace something that used to declare something. Works on compilers that require declarations before any code.
dNOOP;
END_EXTERN_C
When not compiling using C++, expands to nothing. Otherwise ends a section of code already begun by a "START_EXTERN_C"
.
END_EXTERN_C
EXTERN_C
When not compiling using C++, expands to nothing. Otherwise is used in a declaration of a function to indicate the function should have external C linkage. This is required for things to work for just about all functions with external linkage compiled into perl. Often, you can use "START_EXTERN_C"
... "END_EXTERN_C"
blocks surrounding all your code that you need to have this linkage.
Example usage:
EXTERN_C int flock(int fd, int op);
LIKELY
Returns the input unchanged, but at the same time it gives a branch prediction hint to the compiler that this condition is likely to be true.
LIKELY(bool expr)
NOOP
Do nothing; typically used as a placeholder to replace something that used to do something.
NOOP;
PERL_UNUSED_ARG
This is used to suppress compiler warnings that a parameter to a function is not used. This situation can arise, for example, when a parameter is needed under some configuration conditions, but not others, so that C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_ARG(void x);
PERL_UNUSED_CONTEXT
This is used to suppress compiler warnings that the thread context parameter to a function is not used. This situation can arise, for example, when a C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_CONTEXT;
PERL_UNUSED_DECL
Tells the compiler that the parameter in the function prototype just before it is not necessarily expected to be used in the function. Not that many compilers understand this, so this should only be used in cases where "PERL_UNUSED_ARG"
can't conveniently be used.
Example usage:
Signal_t Perl_perly_sighandler(int sig, Siginfo_t *sip PERL_UNUSED_DECL, void *uap PERL_UNUSED_DECL, bool safe)
PERL_UNUSED_RESULT
This macro indicates to discard the return value of the function call inside it, e.g.,
PERL_UNUSED_RESULT(foo(a, b))
The main reason for this is that the combination of gcc -Wunused-result
(part of -Wall
) and the __attribute__((warn_unused_result))
cannot be silenced with casting to void
. This causes trouble when the system header files use the attribute.
Use PERL_UNUSED_RESULT
sparingly, though, since usually the warning is there for a good reason: you might lose success/failure information, or leak resources, or changes in resources.
But sometimes you just want to ignore the return value, e.g., on codepaths soon ending up in abort, or in "best effort" attempts, or in situations where there is no good way to handle failures.
Sometimes PERL_UNUSED_RESULT
might not be the most natural way: another possibility is that you can capture the return value and use "PERL_UNUSED_VAR"
on that.
PERL_UNUSED_RESULT(void x)
PERL_UNUSED_VAR
This is used to suppress compiler warnings that the variable x is not used. This situation can arise, for example, when a C preprocessor conditional compilation causes it be used just some times.
PERL_UNUSED_VAR(void x);
PERL_USE_GCC_BRACE_GROUPS
This C pre-processor value, if defined, indicates that it is permissible to use the GCC brace groups extension. This extension, of the form
({ statement ... })
turns the block consisting of statements ... into an expression with a value, unlike plain C language blocks. This can present optimization possibilities, BUT you generally need to specify an alternative in case this ability doesn't exist or has otherwise been forbidden.
Example usage:
#ifdef PERL_USE_GCC_BRACE_GROUPS ... #else ... #endif
START_EXTERN_C
When not compiling using C++, expands to nothing. Otherwise begins a section of code in which every function will effectively have "EXTERN_C"
applied to it, that is to have external C linkage. The section is ended by a "END_EXTERN_C"
.
START_EXTERN_C
STATIC
Described in perlguts.
STMT_START
STMT_END
This allows a series of statements in a macro to be used as a single statement, as in
if (x) STMT_START { ... } STMT_END else ...
Note that you can't return a value out of them, which limits their utility. But see "PERL_USE_GCC_BRACE_GROUPS"
.
UNLIKELY
Returns the input unchanged, but at the same time it gives a branch prediction hint to the compiler that this condition is likely to be false.
UNLIKELY(bool expr)
__ASSERT_
This is a helper macro to avoid preprocessor issues, replaced by nothing unless under DEBUGGING, where it expands to an assert of its argument, followed by a comma (hence the comma operator). If we just used a straight assert(), we would get a comma with nothing before it when not DEBUGGING.
__ASSERT_(bool expr)
BhkDISABLE
NOTE: BhkDISABLE
is experimental and may change or be removed without notice.
Temporarily disable an entry in this BHK structure, by clearing the appropriate flag. which
is a preprocessor token indicating which entry to disable.
void BhkDISABLE(BHK *hk, which)
BhkENABLE
NOTE: BhkENABLE
is experimental and may change or be removed without notice.
Re-enable an entry in this BHK structure, by setting the appropriate flag. which
is a preprocessor token indicating which entry to enable. This will assert (under -DDEBUGGING) if the entry doesn't contain a valid pointer.
void BhkENABLE(BHK *hk, which)
BhkENTRY_set
NOTE: BhkENTRY_set
is experimental and may change or be removed without notice.
Set an entry in the BHK structure, and set the flags to indicate it is valid. which
is a preprocessing token indicating which entry to set. The type of ptr
depends on the entry.
void BhkENTRY_set(BHK *hk, which, void *ptr)
blockhook_register
NOTE: blockhook_register
is experimental and may change or be removed without notice.
Register a set of hooks to be called when the Perl lexical scope changes at compile time. See "Compile-time scope hooks" in perlguts.
NOTE: blockhook_register
must be explicitly called as Perl_blockhook_register
with an aTHX_
parameter.
void Perl_blockhook_register(pTHX_ BHK *hk)
aTHX
Described in perlguts.
aTHX_
Described in perlguts.
CPERLscope
DEPRECATED!
It is planned to remove CPERLscope
from a future release of Perl. Do not use it for new code; remove it from existing code.
Now a no-op.
void CPERLscope(void x)
dTHR
Described in perlguts.
dTHX
Described in perlguts.
dTHXoa
Now a synonym for "dTHXa"
.
GETENV_PRESERVES_OTHER_THREAD
This symbol, if defined, indicates that the getenv system call doesn't zap the static buffer of getenv()
in a different thread. The typical getenv()
implementation will return a pointer to the proper position in **environ. But some may instead copy them to a static buffer in getenv()
. If there is a per-thread instance of that buffer, or the return points to **environ, then a many-reader/1-writer mutex will work; otherwise an exclusive locking mutex is required to prevent races.
HAS_PTHREAD_ATFORK
This symbol, if defined, indicates that the pthread_atfork
routine is available to setup fork handlers.
HAS_PTHREAD_ATTR_SETSCOPE
This symbol, if defined, indicates that the pthread_attr_setscope
system call is available to set the contention scope attribute of a thread attribute object.
HAS_PTHREAD_YIELD
This symbol, if defined, indicates that the pthread_yield
routine is available to yield the execution of the current thread. sched_yield
is preferable to pthread_yield
.
HAS_SCHED_YIELD
This symbol, if defined, indicates that the sched_yield
routine is available to yield the execution of the current thread. sched_yield
is preferable to pthread_yield
.
I_MACH_CTHREADS
This symbol, if defined, indicates to the C program that it should include mach/cthreads.h.
#ifdef I_MACH_CTHREADS #include <mach_cthreads.h> #endif
I_PTHREAD
This symbol, if defined, indicates to the C program that it should include pthread.h.
#ifdef I_PTHREAD #include <pthread.h> #endif
MULTIPLICITY
This symbol, if defined, indicates that Perl should be built to use multiplicity.
OLD_PTHREADS_API
This symbol, if defined, indicates that Perl should be built to use the old draft POSIX
threads API
.
OLD_PTHREAD_CREATE_JOINABLE
This symbol, if defined, indicates how to create pthread in joinable (aka undetached) state. NOTE
: not defined if pthread.h already has defined PTHREAD_CREATE_JOINABLE
(the new version of the constant). If defined, known values are PTHREAD_CREATE_UNDETACHED
and __UNDETACHED
.
PERL_IMPLICIT_CONTEXT
Described in perlguts.
pTHX
Described in perlguts.
pTHX_
Described in perlguts.
cop_fetch_label
NOTE: cop_fetch_label
is experimental and may change or be removed without notice.
Returns the label attached to a cop, and stores its length in bytes into *len
. Upon return, *flags
will be set to either SVf_UTF8
or 0.
Alternatively, use the macro "CopLABEL_len_flags"
; or if you don't need to know if the label is UTF-8 or not, the macro "CopLABEL_len"
; or if you additionally dont need to know the length, "CopLABEL"
.
const char * cop_fetch_label(COP *const cop, STRLEN *len, U32 *flags)
CopFILEAV
Returns the AV associated with the COP
c
, creating it if necessary.
AV * CopFILEAV(const COP * c)
CopFILEAVn
Returns the AV associated with the COP
c
, returning NULL if it doesn't already exist.
AV * CopFILEAVn(const COP * c)
CopFILEGV_set
Available only on unthreaded perls. Makes pv
the name of the file associated with the COP
c
void CopFILEGV_set(COP * c, GV * gv)
CopFILE_set
Makes pv
the name of the file associated with the COP
c
void CopFILE_set(COP * c, const char * pv)
cophh_2hv
NOTE: cophh_2hv
is experimental and may change or be removed without notice.
Generates and returns a standard Perl hash representing the full set of key/value pairs in the cop hints hash cophh
. flags
is currently unused and must be zero.
HV * cophh_2hv(const COPHH *cophh, U32 flags)
cophh_copy
NOTE: cophh_copy
is experimental and may change or be removed without notice.
Make and return a complete copy of the cop hints hash cophh
.
COPHH * cophh_copy(COPHH *cophh)
cophh_delete_pvn
cophh_delete_pv
cophh_delete_pvs
cophh_delete_sv
NOTE: all these forms are experimental and may change or be removed without notice.
These delete a key and its associated value from the cop hints hash cophh
, and return the modified hash. The returned hash pointer is in general not the same as the hash pointer that was passed in. The input hash is consumed by the function, and the pointer to it must not be subsequently used. Use "cophh_copy" if you need both hashes.
The forms differ in how the key is specified. In all forms, the key is pointed to by key
. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_delete_pvn(COPHH *cophh, const char *key, STRLEN keylen, U32 hash, U32 flags) COPHH * cophh_delete_pv (COPHH *cophh, const char *key, U32 hash, U32 flags) COPHH * cophh_delete_pvs(COPHH *cophh, "key", U32 flags) COPHH * cophh_delete_sv (COPHH *cophh, SV *key, U32 hash, U32 flags)
cophh_exists_pvn
NOTE: cophh_exists_pvn
is experimental and may change or be removed without notice.
These look up the hint entry in the cop cop
with the key specified by key
(and keylen
in the pvn
form), returning true if a value exists, and false otherwise.
The forms differ in how the key is specified. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
bool cophh_exists_pvn(const COPHH *cophh, const char *key, STRLEN keylen, U32 hash, U32 flags)
cophh_fetch_pvn
cophh_fetch_pv
cophh_fetch_pvs
cophh_fetch_sv
NOTE: all these forms are experimental and may change or be removed without notice.
These look up the entry in the cop hints hash cophh
with the key specified by key
(and keylen
in the pvn
form), returning that value as a mortal scalar copy, or &PL_sv_placeholder
if there is no value associated with the key.
The forms differ in how the key is specified. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
SV * cophh_fetch_pvn(const COPHH *cophh, const char *key, STRLEN keylen, U32 hash, U32 flags) SV * cophh_fetch_pv (const COPHH *cophh, const char *key, U32 hash, U32 flags) SV * cophh_fetch_pvs(const COPHH *cophh, "key", U32 flags) SV * cophh_fetch_sv (const COPHH *cophh, SV *key, U32 hash, U32 flags)
cophh_free
NOTE: cophh_free
is experimental and may change or be removed without notice.
Discard the cop hints hash cophh
, freeing all resources associated with it.
void cophh_free(COPHH *cophh)
cophh_new_empty
NOTE: cophh_new_empty
is experimental and may change or be removed without notice.
Generate and return a fresh cop hints hash containing no entries.
COPHH * cophh_new_empty()
cophh_store_pvn
cophh_store_pv
cophh_store_pvs
cophh_store_sv
NOTE: all these forms are experimental and may change or be removed without notice.
These store a value, associated with a key, in the cop hints hash cophh
, and return the modified hash. The returned hash pointer is in general not the same as the hash pointer that was passed in. The input hash is consumed by the function, and the pointer to it must not be subsequently used. Use "cophh_copy" if you need both hashes.
value
is the scalar value to store for this key. value
is copied by these functions, which thus do not take ownership of any reference to it, and hence later changes to the scalar will not be reflected in the value visible in the cop hints hash. Complex types of scalar will not be stored with referential integrity, but will be coerced to strings.
The forms differ in how the key is specified. In all forms, the key is pointed to by key
. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
COPHH * cophh_store_pvn(COPHH *cophh, const char *key, STRLEN keylen, U32 hash, SV *value, U32 flags) COPHH * cophh_store_pv (COPHH *cophh, const char *key, U32 hash, SV *value, U32 flags) COPHH * cophh_store_pvs(COPHH *cophh, "key", SV *value, U32 flags) COPHH * cophh_store_sv (COPHH *cophh, SV *key, U32 hash, SV *value, U32 flags)
cop_hints_2hv
Generates and returns a standard Perl hash representing the full set of hint entries in the cop cop
. flags
is currently unused and must be zero.
HV * cop_hints_2hv(const COP *cop, U32 flags)
cop_hints_exists_pvn
cop_hints_exists_pv
cop_hints_exists_pvs
cop_hints_exists_sv
These look up the hint entry in the cop cop
with the key specified by key
(and keylen
in the pvn
form), returning true if a value exists, and false otherwise.
The forms differ in how the key is specified. In all forms, the key is pointed to by key
. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
bool cop_hints_exists_pvn(const COP *cop, const char *key, STRLEN keylen, U32 hash, U32 flags) bool cop_hints_exists_pv (const COP *cop, const char *key, U32 hash, U32 flags) bool cop_hints_exists_pvs(const COP *cop, "key", U32 flags) bool cop_hints_exists_sv (const COP *cop, SV *key, U32 hash, U32 flags)
cop_hints_fetch_pvn
cop_hints_fetch_pv
cop_hints_fetch_pvs
cop_hints_fetch_sv
These look up the hint entry in the cop cop
with the key specified by key
(and keylen
in the pvn
form), returning that value as a mortal scalar copy, or &PL_sv_placeholder
if there is no value associated with the key.
The forms differ in how the key is specified. In the plain pv
form, the key is a C language NUL-terminated string. In the pvs
form, the key is a C language string literal. In the pvn
form, an additional parameter, keylen
, specifies the length of the string, which hence, may contain embedded-NUL characters. In the sv
form, *key
is an SV, and the key is the PV extracted from that. using "SvPV_const"
.
hash
is a precomputed hash of the key string, or zero if it has not been precomputed. This parameter is omitted from the pvs
form, as it is computed automatically at compile time.
The only flag currently used from the flags
parameter is COPHH_KEY_UTF8
. It is illegal to set this in the sv
form. In the pv*
forms, it specifies whether the key octets are interpreted as UTF-8 (if set) or as Latin-1 (if cleared). The sv
form uses the underlying SV to determine the UTF-8ness of the octets.
SV * cop_hints_fetch_pvn(const COP *cop, const char *key, STRLEN keylen, U32 hash, U32 flags) SV * cop_hints_fetch_pv (const COP *cop, const char *key, U32 hash, U32 flags) SV * cop_hints_fetch_pvs(const COP *cop, "key", U32 flags) SV * cop_hints_fetch_sv (const COP *cop, SV *key, U32 hash, U32 flags)
CopLABEL
CopLABEL_len
CopLABEL_len_flags
These return the label attached to a cop.
CopLABEL_len
and CopLABEL_len_flags
additionally store the number of bytes comprising the returned label into *len
.
CopLABEL_len_flags
additionally returns the UTF-8ness of the returned label, by setting *flags
to 0 or SVf_UTF8
.
const char * CopLABEL (COP *const cop) const char * CopLABEL_len (COP *const cop, STRLEN *len) const char * CopLABEL_len_flags(COP *const cop, STRLEN *len, U32 *flags)
CopLINE
Returns the line number in the source code associated with the COP
c
STRLEN CopLINE(const COP * c)
CopSTASH_eq
Returns a boolean as to whether or not hv
is the stash associated with c
.
bool CopSTASH_eq(const COP * c, const HV * hv)
CopSTASHPV
Returns the package name of the stash associated with c
, or NULL
if no associated stash
char * CopSTASHPV(const COP * c)
CopSTASHPV_set
Set the package name of the stash associated with c
, to the NUL-terminated C string p
, creating the package if necessary.
void CopSTASHPV_set(COP * c, const char * pv)
custom_op_desc
DEPRECATED!
It is planned to remove custom_op_desc
from a future release of Perl. Do not use it for new code; remove it from existing code.
Return the description of a given custom op. This was once used by the OP_DESC
macro, but is no longer: it has only been kept for compatibility, and should not be used.
const char * custom_op_desc(const OP *o)
custom_op_name
DEPRECATED!
It is planned to remove custom_op_name
from a future release of Perl. Do not use it for new code; remove it from existing code.
Return the name for a given custom op. This was once used by the OP_NAME
macro, but is no longer: it has only been kept for compatibility, and should not be used.
const char * custom_op_name(const OP *o)
custom_op_register
Register a custom op. See "Custom Operators" in perlguts.
NOTE: custom_op_register
must be explicitly called as Perl_custom_op_register
with an aTHX_
parameter.
void Perl_custom_op_register(pTHX_ Perl_ppaddr_t ppaddr, const XOP *xop)
Perl_custom_op_xop
Return the XOP structure for a given custom op. This macro should be considered internal to OP_NAME
and the other access macros: use them instead. This macro does call a function. Prior to 5.19.6, this was implemented as a function.
const XOP * Perl_custom_op_xop(pTHX_ const OP *o)
XopDISABLE
Temporarily disable a member of the XOP, by clearing the appropriate flag.
void XopDISABLE(XOP *xop, which)
XopENTRY
Return a member of the XOP structure. which
is a cpp token indicating which entry to return. If the member is not set this will return a default value. The return type depends on which
. This macro evaluates its arguments more than once. If you are using Perl_custom_op_xop
to retrieve a XOP *
from a OP *
, use the more efficient "XopENTRYCUSTOM" instead.
XopENTRY(XOP *xop, which)
XopENTRYCUSTOM
Exactly like XopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which)
but more efficient. The which
parameter is identical to "XopENTRY".
XopENTRYCUSTOM(const OP *o, which)
XopENTRY_set
Set a member of the XOP structure. which
is a cpp token indicating which entry to set. See "Custom Operators" in perlguts for details about the available members and how they are used. This macro evaluates its argument more than once.
void XopENTRY_set(XOP *xop, which, value)
This section documents functions to manipulate CVs which are code-values, meaning subroutines. For more information, see perlguts.
caller_cx
The XSUB-writer's equivalent of caller(). The returned PERL_CONTEXT
structure can be interrogated to find all the information returned to Perl by caller
. Note that XSUBs don't get a stack frame, so caller_cx(0, NULL)
will return information for the immediately-surrounding Perl code.
This function skips over the automatic calls to &DB::sub
made on the behalf of the debugger. If the stack frame requested was a sub called by DB::sub
, the return value will be the frame for the call to DB::sub
, since that has the correct line number/etc. for the call site. If dbcxp is non-NULL
, it will be set to a pointer to the frame for the sub call itself.
const PERL_CONTEXT * caller_cx(I32 level, const PERL_CONTEXT **dbcxp)
CvDEPTH
Returns the recursion level of the CV sv
. Hence >= 2 indicates we are in a recursive call.
I32 * CvDEPTH(const CV * const sv)
CvSTASH
Returns the stash of the CV. A stash is the symbol table hash, containing the package-scoped variables in the package where the subroutine was defined. For more information, see perlguts.
This also has a special use with XS AUTOLOAD subs. See "Autoloading with XSUBs" in perlguts.
HV* CvSTASH(CV* cv)
find_runcv
Locate the CV corresponding to the currently executing sub or eval. If db_seqp
is non_null, skip CVs that are in the DB package and populate *db_seqp
with the cop sequence number at the point that the DB:: code was entered. (This allows debuggers to eval in the scope of the breakpoint rather than in the scope of the debugger itself.)
CV* find_runcv(U32 *db_seqp)
get_cv
get_cvs
get_cvn_flags
These return the CV of the specified Perl subroutine. flags
are passed to gv_fetchpvn_flags
. If GV_ADD
is set and the Perl subroutine does not exist then it will be declared (which has the same effect as saying sub name;
). If GV_ADD
is not set and the subroutine does not exist, then NULL is returned.
The forms differ only in how the subroutine is specified.. With get_cvs
, the name is a literal C string, enclosed in double quotes. With get_cv
, the name is given by the name
parameter, which must be a NUL-terminated C string. With get_cvn_flags
, the name is also given by the name
parameter, but it is a Perl string (possibly containing embedded NUL bytes), and its length in bytes is contained in the len
parameter.
NOTE: the perl_get_cv()
form is deprecated.
NOTE: the perl_get_cvs()
form is deprecated.
NOTE: the perl_get_cvn_flags()
form is deprecated.
CV* get_cv (const char* name, I32 flags) CV * get_cvs ("string", I32 flags) CV* get_cvn_flags(const char* name, STRLEN len, I32 flags)
deb
deb_nocontext
When perl is compiled with -DDEBUGGING
, this prints to STDERR the information given by the arguments, prefaced by the name of the file containing the script causing the call, and the line number within that file.
If the v
(verbose) debugging option is in effect, the process id is also printed.
The two forms differ only in that deb_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: deb
must be explicitly called as Perl_deb
with an aTHX_
parameter.
void Perl_deb (pTHX_ const char* pat, ...) void deb_nocontext(const char* pat, ...)
dump_all
Dumps the entire optree of the current program starting at PL_main_root
to STDERR
. Also dumps the optrees for all visible subroutines in PL_defstash
.
void dump_all()
dump_c_backtrace
Dumps the C backtrace to the given fp
.
Returns true if a backtrace could be retrieved, false if not.
bool dump_c_backtrace(PerlIO* fp, int max_depth, int skip)
dump_eval
Described in perlguts.
void dump_eval()
dump_form
Dumps the contents of the format contained in the GV gv
to STDERR
, or a message that one doesn't exist.
void dump_form(const GV* gv)
dump_packsubs
Dumps the optrees for all visible subroutines in stash
.
void dump_packsubs(const HV* stash)
dump_sub
Described in perlguts.
void dump_sub(const GV* gv)
get_c_backtrace_dump
Returns a SV containing a dump of depth
frames of the call stack, skipping the skip
innermost ones. depth
of 20 is usually enough.
The appended output looks like:
... 1 10e004812:0082 Perl_croak util.c:1716 /usr/bin/perl 2 10df8d6d2:1d72 perl_parse perl.c:3975 /usr/bin/perl ...
The fields are tab-separated. The first column is the depth (zero being the innermost non-skipped frame). In the hex:offset, the hex is where the program counter was in S_parse_body
, and the :offset (might be missing) tells how much inside the S_parse_body
the program counter was.
The util.c:1716
is the source code file and line number.
The /usr/bin/perl is obvious (hopefully).
Unknowns are "-"
. Unknowns can happen unfortunately quite easily: if the platform doesn't support retrieving the information; if the binary is missing the debug information; if the optimizer has transformed the code by for example inlining.
SV* get_c_backtrace_dump(int max_depth, int skip)
gv_dump
Dump the name and, if they differ, the effective name of the GV gv
to STDERR
.
void gv_dump(GV* gv)
HAS_BACKTRACE
This symbol, if defined, indicates that the backtrace()
routine is available to get a stack trace. The execinfo.h header must be included to use this routine.
op_class
Given an op, determine what type of struct it has been allocated as. Returns one of the OPclass enums, such as OPclass_LISTOP.
OPclass op_class(const OP *o)
PL_op
Described in perlhacktips.
PL_runops
Described in perlguts.
PL_sv_serial
Described in perlhacktips.
pmop_dump
Dump an OP that is related to Pattern Matching, such as s/foo/bar/
; these require special handling.
void pmop_dump(PMOP* pm)
sv_dump
Dumps the contents of an SV to the STDERR
filehandle.
For an example of its output, see Devel::Peek.
void sv_dump(SV* sv)
vdeb
This is like "deb"
, but args
are an encapsulated argument list.
void vdeb(const char* pat, va_list* args)
form
form_nocontext
These take a sprintf-style format pattern and conventional (non-SV) arguments and return the formatted string.
(char *) Perl_form(pTHX_ const char* pat, ...)
can be used any place a string (char *) is required:
char * s = Perl_form("%d.%d",major,minor);
They use a single (per-thread) private buffer so if you want to format several strings you must explicitly copy the earlier strings away (and free the copies when you are done).
The two forms differ only in that form_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: form
must be explicitly called as Perl_form
with an aTHX_
parameter.
char* Perl_form (pTHX_ const char* pat, ...) char* form_nocontext(const char* pat, ...)
mess
mess_nocontext
These take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv"
.
Normally, the resulting message is returned in a new mortal SV. But during global destruction a single SV may be shared between uses of this function.
The two forms differ only in that mess_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: mess
must be explicitly called as Perl_mess
with an aTHX_
parameter.
SV* Perl_mess (pTHX_ const char* pat, ...) SV* mess_nocontext(const char* pat, ...)
mess_sv
Expands a message, intended for the user, to include an indication of the current location in the code, if the message does not already appear to be complete.
basemsg
is the initial message or object. If it is a reference, it will be used as-is and will be the result of this function. Otherwise it is used as a string, and if it already ends with a newline, it is taken to be complete, and the result of this function will be the same string. If the message does not end with a newline, then a segment such as at foo.pl line 37
will be appended, and possibly other clauses indicating the current state of execution. The resulting message will end with a dot and a newline.
Normally, the resulting message is returned in a new mortal SV. During global destruction a single SV may be shared between uses of this function. If consume
is true, then the function is permitted (but not required) to modify and return basemsg
instead of allocating a new SV.
SV* mess_sv(SV* basemsg, bool consume)
pv_display
Similar to
pv_escape(dsv,pv,cur,pvlim,PERL_PV_ESCAPE_QUOTE);
except that an additional "\0" will be appended to the string when len > cur and pv[cur] is "\0".
Note that the final string may be up to 7 chars longer than pvlim.
char* pv_display(SV *dsv, const char *pv, STRLEN cur, STRLEN len, STRLEN pvlim)
pv_escape
Escapes at most the first count
chars of pv
and puts the results into dsv
such that the size of the escaped string will not exceed max
chars and will not contain any incomplete escape sequences. The number of bytes escaped will be returned in the STRLEN *escaped
parameter if it is not null. When the dsv
parameter is null no escaping actually occurs, but the number of bytes that would be escaped were it not null will be calculated.
If flags contains PERL_PV_ESCAPE_QUOTE
then any double quotes in the string will also be escaped.
Normally the SV will be cleared before the escaped string is prepared, but when PERL_PV_ESCAPE_NOCLEAR
is set this will not occur.
If PERL_PV_ESCAPE_UNI
is set then the input string is treated as UTF-8 if PERL_PV_ESCAPE_UNI_DETECT
is set then the input string is scanned using is_utf8_string()
to determine if it is UTF-8.
If PERL_PV_ESCAPE_ALL
is set then all input chars will be output using \x01F1
style escapes, otherwise if PERL_PV_ESCAPE_NONASCII
is set, only non-ASCII chars will be escaped using this style; otherwise, only chars above 255 will be so escaped; other non printable chars will use octal or common escaped patterns like \n
. Otherwise, if PERL_PV_ESCAPE_NOBACKSLASH
then all chars below 255 will be treated as printable and will be output as literals.
If PERL_PV_ESCAPE_FIRSTCHAR
is set then only the first char of the string will be escaped, regardless of max. If the output is to be in hex, then it will be returned as a plain hex sequence. Thus the output will either be a single char, an octal escape sequence, a special escape like \n
or a hex value.
If PERL_PV_ESCAPE_RE
is set then the escape char used will be a "%"
and not a "\\"
. This is because regexes very often contain backslashed sequences, whereas "%"
is not a particularly common character in patterns.
Returns a pointer to the escaped text as held by dsv
.
char* pv_escape(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, STRLEN * const escaped, const U32 flags)
pv_pretty
Converts a string into something presentable, handling escaping via pv_escape()
and supporting quoting and ellipses.
If the PERL_PV_PRETTY_QUOTE
flag is set then the result will be double quoted with any double quotes in the string escaped. Otherwise if the PERL_PV_PRETTY_LTGT
flag is set then the result be wrapped in angle brackets.
If the PERL_PV_PRETTY_ELLIPSES
flag is set and not all characters in string were output then an ellipsis ...
will be appended to the string. Note that this happens AFTER it has been quoted.
If start_color
is non-null then it will be inserted after the opening quote (if there is one) but before the escaped text. If end_color
is non-null then it will be inserted after the escaped text but before any quotes or ellipses.
Returns a pointer to the prettified text as held by dsv
.
char* pv_pretty(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, char const * const start_color, char const * const end_color, const U32 flags)
vform
Like "form"
but but the arguments are an encapsulated argument list.
char* vform(const char* pat, va_list* args)
vmess
pat
and args
are a sprintf-style format pattern and encapsulated argument list, respectively. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv".
Normally, the resulting message is returned in a new mortal SV. During global destruction a single SV may be shared between uses of this function.
SV* vmess(const char* pat, va_list* args)
call_atexit
Add a function fn
to the list of functions to be called at global destruction. ptr
will be passed as an argument to fn
; it can point to a struct
so that you can pass anything you want.
Note that under threads, fn
may run multiple times. This is because the list is executed each time the current or any descendent thread terminates.
void call_atexit(ATEXIT_t fn, void *ptr)
cv_clone
Clone a CV, making a lexical closure. proto
supplies the prototype of the function: its code, pad structure, and other attributes. The prototype is combined with a capture of outer lexicals to which the code refers, which are taken from the currently-executing instance of the immediately surrounding code.
CV* cv_clone(CV* proto)
cv_name
Returns an SV containing the name of the CV, mainly for use in error reporting. The CV may actually be a GV instead, in which case the returned SV holds the GV's name. Anything other than a GV or CV is treated as a string already holding the sub name, but this could change in the future.
An SV may be passed as a second argument. If so, the name will be assigned to it and it will be returned. Otherwise the returned SV will be a new mortal.
If flags
has the CV_NAME_NOTQUAL
bit set, then the package name will not be included. If the first argument is neither a CV nor a GV, this flag is ignored (subject to change).
SV * cv_name(CV *cv, SV *sv, U32 flags)
cv_undef
Clear out all the active components of a CV. This can happen either by an explicit undef &foo
, or by the reference count going to zero. In the former case, we keep the CvOUTSIDE
pointer, so that any anonymous children can still follow the full lexical scope chain.
void cv_undef(CV* cv)
find_rundefsvoffset
DEPRECATED!
It is planned to remove find_rundefsvoffset
from a future release of Perl. Do not use it for new code; remove it from existing code.
Until the lexical $_
feature was removed, this function would find the position of the lexical $_
in the pad of the currently-executing function and return the offset in the current pad, or NOT_IN_PAD
.
Now it always returns NOT_IN_PAD
.
PADOFFSET find_rundefsvoffset()
HAS_SKIP_LOCALE_INIT
Described in perlembed.
intro_my
"Introduce" my
variables to visible status. This is called during parsing at the end of each statement to make lexical variables visible to subsequent statements.
U32 intro_my()
load_module
load_module_nocontext
These load the module whose name is pointed to by the string part of name
. Note that the actual module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". ver, if specified and not NULL, provides version semantics similar to use Foo::Bar VERSION
. The optional trailing arguments can be used to specify arguments to the module's import()
method, similar to use Foo::Bar VERSION LIST
; their precise handling depends on the flags. The flags argument is a bitwise-ORed collection of any of PERL_LOADMOD_DENY
, PERL_LOADMOD_NOIMPORT
, or PERL_LOADMOD_IMPORT_OPS
(or 0 for no flags).
If PERL_LOADMOD_NOIMPORT
is set, the module is loaded as if with an empty import list, as in use Foo::Bar ()
; this is the only circumstance in which the trailing optional arguments may be omitted entirely. Otherwise, if PERL_LOADMOD_IMPORT_OPS
is set, the trailing arguments must consist of exactly one OP*
, containing the op tree that produces the relevant import arguments. Otherwise, the trailing arguments must all be SV*
values that will be used as import arguments; and the list must be terminated with (SV*) NULL
. If neither PERL_LOADMOD_NOIMPORT
nor PERL_LOADMOD_IMPORT_OPS
is set, the trailing NULL
pointer is needed even if no import arguments are desired. The reference count for each specified SV*
argument is decremented. In addition, the name
argument is modified.
If PERL_LOADMOD_DENY
is set, the module is loaded as if with no
rather than use
.
load_module
and load_module_nocontext
have the same apparent signature, but the former hides the fact that it is accessing a thread context parameter. So use the latter when you get a compilation error about pTHX
.
void load_module (U32 flags, SV* name, SV* ver, ...) void load_module_nocontext(U32 flags, SV* name, SV* ver, ...)
my_exit
A wrapper for the C library exit(3), honoring what "PL_exit_flags" in perlapi say to do.
void my_exit(U32 status)
newPADNAMELIST
NOTE: newPADNAMELIST
is experimental and may change or be removed without notice.
Creates a new pad name list. max
is the highest index for which space is allocated.
PADNAMELIST * newPADNAMELIST(size_t max)
newPADNAMEouter
NOTE: newPADNAMEouter
is experimental and may change or be removed without notice.
Constructs and returns a new pad name. Only use this function for names that refer to outer lexicals. (See also "newPADNAMEpvn".) outer
is the outer pad name that this one mirrors. The returned pad name has the PADNAMEt_OUTER
flag already set.
PADNAME * newPADNAMEouter(PADNAME *outer)
newPADNAMEpvn
NOTE: newPADNAMEpvn
is experimental and may change or be removed without notice.
Constructs and returns a new pad name. s
must be a UTF-8 string. Do not use this for pad names that point to outer lexicals. See "newPADNAMEouter"
.
PADNAME * newPADNAMEpvn(const char *s, STRLEN len)
nothreadhook
Stub that provides thread hook for perl_destruct when there are no threads.
int nothreadhook()
pad_add_anon
Allocates a place in the currently-compiling pad (via "pad_alloc") for an anonymous function that is lexically scoped inside the currently-compiling function. The function func
is linked into the pad, and its CvOUTSIDE
link to the outer scope is weakened to avoid a reference loop.
One reference count is stolen, so you may need to do SvREFCNT_inc(func)
.
optype
should be an opcode indicating the type of operation that the pad entry is to support. This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_add_anon(CV* func, I32 optype)
pad_add_name_pv
Exactly like "pad_add_name_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_add_name_pv(const char *name, const U32 flags, HV *typestash, HV *ourstash)
pad_add_name_pvn
Allocates a place in the currently-compiling pad for a named lexical variable. Stores the name and other metadata in the name part of the pad, and makes preparations to manage the variable's lexical scoping. Returns the offset of the allocated pad slot.
namepv
/namelen
specify the variable's name, including leading sigil. If typestash
is non-null, the name is for a typed lexical, and this identifies the type. If ourstash
is non-null, it's a lexical reference to a package variable, and this identifies the package. The following flags can be OR'ed together:
padadd_OUR redundantly specifies if it's a package var padadd_STATE variable will retain value persistently padadd_NO_DUP_CHECK skip check for lexical shadowing
PADOFFSET pad_add_name_pvn(const char *namepv, STRLEN namelen, U32 flags, HV *typestash, HV *ourstash)
pad_add_name_sv
Exactly like "pad_add_name_pvn", but takes the name string in the form of an SV instead of a string/length pair.
PADOFFSET pad_add_name_sv(SV *name, U32 flags, HV *typestash, HV *ourstash)
pad_alloc
NOTE: pad_alloc
is experimental and may change or be removed without notice.
Allocates a place in the currently-compiling pad, returning the offset of the allocated pad slot. No name is initially attached to the pad slot. tmptype
is a set of flags indicating the kind of pad entry required, which will be set in the value SV for the allocated pad entry:
SVs_PADMY named lexical variable ("my", "our", "state") SVs_PADTMP unnamed temporary store SVf_READONLY constant shared between recursion levels
SVf_READONLY
has been supported here only since perl 5.20. To work with earlier versions as well, use SVf_READONLY|SVs_PADTMP
. SVf_READONLY
does not cause the SV in the pad slot to be marked read-only, but simply tells pad_alloc
that it will be made read-only (by the caller), or at least should be treated as such.
optype
should be an opcode indicating the type of operation that the pad entry is to support. This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_alloc(I32 optype, U32 tmptype)
pad_findmy_pv
Exactly like "pad_findmy_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_findmy_pv(const char* name, U32 flags)
pad_findmy_pvn
Given the name of a lexical variable, find its position in the currently-compiling pad. namepv
/namelen
specify the variable's name, including leading sigil. flags
is reserved and must be zero. If it is not in the current pad but appears in the pad of any lexically enclosing scope, then a pseudo-entry for it is added in the current pad. Returns the offset in the current pad, or NOT_IN_PAD
if no such lexical is in scope.
PADOFFSET pad_findmy_pvn(const char* namepv, STRLEN namelen, U32 flags)
pad_findmy_sv
Exactly like "pad_findmy_pvn", but takes the name string in the form of an SV instead of a string/length pair.
PADOFFSET pad_findmy_sv(SV* name, U32 flags)
padnamelist_fetch
NOTE: padnamelist_fetch
is experimental and may change or be removed without notice.
Fetches the pad name from the given index.
PADNAME * padnamelist_fetch(PADNAMELIST *pnl, SSize_t key)
padnamelist_store
NOTE: padnamelist_store
is experimental and may change or be removed without notice.
Stores the pad name (which may be null) at the given index, freeing any existing pad name in that slot.
PADNAME ** padnamelist_store(PADNAMELIST *pnl, SSize_t key, PADNAME *val)
pad_tidy
NOTE: pad_tidy
is experimental and may change or be removed without notice.
Tidy up a pad at the end of compilation of the code to which it belongs. Jobs performed here are: remove most stuff from the pads of anonsub prototypes; give it a @_
; mark temporaries as such. type
indicates the kind of subroutine:
padtidy_SUB ordinary subroutine padtidy_SUBCLONE prototype for lexical closure padtidy_FORMAT format
void pad_tidy(padtidy_type type)
perl_alloc
Allocates a new Perl interpreter. See perlembed.
PerlInterpreter* perl_alloc()
PERL_ASYNC_CHECK
Described in perlinterp.
void PERL_ASYNC_CHECK()
perl_construct
Initializes a new Perl interpreter. See perlembed.
void perl_construct(PerlInterpreter *my_perl)
perl_destruct
Shuts down a Perl interpreter. See perlembed for a tutorial.
my_perl
points to the Perl interpreter. It must have been previously created through the use of "perl_alloc" and "perl_construct". It may have been initialised through "perl_parse", and may have been used through "perl_run" and other means. This function should be called for any Perl interpreter that has been constructed with "perl_construct", even if subsequent operations on it failed, for example if "perl_parse" returned a non-zero value.
If the interpreter's PL_exit_flags
word has the PERL_EXIT_DESTRUCT_END
flag set, then this function will execute code in END
blocks before performing the rest of destruction. If it is desired to make any use of the interpreter between "perl_parse" and "perl_destruct" other than just calling "perl_run", then this flag should be set early on. This matters if "perl_run" will not be called, or if anything else will be done in addition to calling "perl_run".
Returns a value be a suitable value to pass to the C library function exit
(or to return from main
), to serve as an exit code indicating the nature of the way the interpreter terminated. This takes into account any failure of "perl_parse" and any early exit from "perl_run". The exit code is of the type required by the host operating system, so because of differing exit code conventions it is not portable to interpret specific numeric values as having specific meanings.
int perl_destruct(PerlInterpreter *my_perl)
perl_free
Releases a Perl interpreter. See perlembed.
void perl_free(PerlInterpreter *my_perl)
PERL_GET_CONTEXT
Described in perlguts.
PerlInterpreter
Described in perlembed.
perl_parse
Tells a Perl interpreter to parse a Perl script. This performs most of the initialisation of a Perl interpreter. See perlembed for a tutorial.
my_perl
points to the Perl interpreter that is to parse the script. It must have been previously created through the use of "perl_alloc" and "perl_construct". xsinit
points to a callback function that will be called to set up the ability for this Perl interpreter to load XS extensions, or may be null to perform no such setup.
argc
and argv
supply a set of command-line arguments to the Perl interpreter, as would normally be passed to the main
function of a C program. argv[argc]
must be null. These arguments are where the script to parse is specified, either by naming a script file or by providing a script in a -e
option. If $0
will be written to in the Perl interpreter, then the argument strings must be in writable memory, and so mustn't just be string constants.
env
specifies a set of environment variables that will be used by this Perl interpreter. If non-null, it must point to a null-terminated array of environment strings. If null, the Perl interpreter will use the environment supplied by the environ
global variable.
This function initialises the interpreter, and parses and compiles the script specified by the command-line arguments. This includes executing code in BEGIN
, UNITCHECK
, and CHECK
blocks. It does not execute INIT
blocks or the main program.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether there was a failure in initialisation. If zero is returned, this indicates that initialisation was successful, and it is safe to proceed to call "perl_run" and make other use of it. If a non-zero value is returned, this indicates some problem that means the interpreter wants to terminate. The interpreter should not be just abandoned upon such failure; the caller should proceed to shut the interpreter down cleanly with "perl_destruct" and free it with "perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library function exit
(or to return from main
), to serve as an exit code indicating the nature of the way initialisation terminated. However, this isn't portable, due to differing exit code conventions. A historical bug is preserved for the time being: if the Perl built-in exit
is called during this function's execution, with a type of exit entailing a zero exit code under the host operating system's conventions, then this function returns zero rather than a non-zero value. This bug, [perl #2754], leads to perl_run
being called (and therefore INIT
blocks and the main program running) despite a call to exit
. It has been preserved because a popular module-installing module has come to rely on it and needs time to be fixed. This issue is [perl #132577], and the original bug is due to be fixed in Perl 5.30.
int perl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit, int argc, char** argv, char** env)
perl_run
Tells a Perl interpreter to run its main program. See perlembed for a tutorial.
my_perl
points to the Perl interpreter. It must have been previously created through the use of "perl_alloc" and "perl_construct", and initialised through "perl_parse". This function should not be called if "perl_parse" returned a non-zero value, indicating a failure in initialisation or compilation.
This function executes code in INIT
blocks, and then executes the main program. The code to be executed is that established by the prior call to "perl_parse". If the interpreter's PL_exit_flags
word does not have the PERL_EXIT_DESTRUCT_END
flag set, then this function will also execute code in END
blocks. If it is desired to make any further use of the interpreter after calling this function, then END
blocks should be postponed to "perl_destruct" time by setting that flag.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether the program terminated non-locally. If zero is returned, this indicates that the program ran to completion, and it is safe to make other use of the interpreter (provided that the PERL_EXIT_DESTRUCT_END
flag was set as described above). If a non-zero value is returned, this indicates that the interpreter wants to terminate early. The interpreter should not be just abandoned because of this desire to terminate; the caller should proceed to shut the interpreter down cleanly with "perl_destruct" and free it with "perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library function exit
(or to return from main
), to serve as an exit code indicating the nature of the way the program terminated. However, this isn't portable, due to differing exit code conventions. An attempt is made to return an exit code of the type required by the host operating system, but because it is constrained to be non-zero, it is not necessarily possible to indicate every type of exit. It is only reliable on Unix, where a zero exit code can be augmented with a set bit that will be ignored. In any case, this function is not the correct place to acquire an exit code: one should get that from "perl_destruct".
int perl_run(PerlInterpreter *my_perl)
PERL_SET_CONTEXT
Described in perlguts.
void PERL_SET_CONTEXT(PerlInterpreter* i)
PERL_SYS_INIT
PERL_SYS_INIT3
These provide system-specific tune up of the C runtime environment necessary to run Perl interpreters. Only one should be used, and it should be called only once, before creating any Perl interpreters.
They differ in that PERL_SYS_INIT3
also initializes env
.
void PERL_SYS_INIT (int *argc, char*** argv) void PERL_SYS_INIT3(int *argc, char*** argv, char*** env)
PERL_SYS_TERM
Provides system-specific clean up of the C runtime environment after running Perl interpreters. This should be called only once, after freeing any remaining Perl interpreters.
void PERL_SYS_TERM()
PL_exit_flags
Contains flags controlling perl's behaviour on exit():
PERL_EXIT_DESTRUCT_END
If set, END blocks are executed when the interpreter is destroyed. This is normally set by perl itself after the interpreter is constructed.
PERL_EXIT_ABORT
Call abort()
on exit. This is used internally by perl itself to abort if exit is called while processing exit.
PERL_EXIT_WARN
Warn on exit.
PERL_EXIT_EXPECTED
Set by the "exit" in perlfunc operator.
U8 PL_exit_flags
PL_origalen
Described in perlembed.
PL_perl_destruct_level
This value may be set when embedding for full cleanup.
Possible values:
If $ENV{PERL_DESTRUCT_LEVEL}
is set to an integer greater than the value of PL_perl_destruct_level
its value is used instead.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
signed char PL_perl_destruct_level
require_pv
Tells Perl to require
the file named by the string argument. It is analogous to the Perl code eval "require '$file'"
. It's even implemented that way; consider using load_module instead.
NOTE: the perl_require_pv()
form is deprecated.
void require_pv(const char* pv)
vload_module
Like "load_module"
but the arguments are an encapsulated argument list.
void vload_module(U32 flags, SV* name, SV* ver, va_list* args)
sv_string_from_errnum
Generates the message string describing an OS error and returns it as an SV. errnum
must be a value that errno
could take, identifying the type of error.
If tgtsv
is non-null then the string will be written into that SV (overwriting existing content) and it will be returned. If tgtsv
is a null pointer then the string will be written into a new mortal SV which will be returned.
The message will be taken from whatever locale would be used by $!
, and will be encoded in the SV in whatever manner would be used by $!
. The details of this process are subject to future change. Currently, the message is taken from the C locale by default (usually producing an English message), and from the currently selected locale when in the scope of the use locale
pragma. A heuristic attempt is made to decode the message from the locale's character encoding, but it will only be decoded as either UTF-8 or ISO-8859-1. It is always correctly decoded in a UTF-8 locale, usually in an ISO-8859-1 locale, and never in any other locale.
The SV is always returned containing an actual string, and with no other OK bits set. Unlike $!
, a message is even yielded for errnum
zero (meaning success), and if no useful message is available then a useless string (currently empty) is returned.
SV* sv_string_from_errnum(int errnum, SV* tgtsv)
dXCPT
Set up necessary local variables for exception handling. See "Exception Handling" in perlguts.
dXCPT;
JMPENV_JUMP
Described in perlinterp.
void JMPENV_JUMP(int v)
JMPENV_PUSH
Described in perlinterp.
void JMPENV_PUSH(int v)
PL_restartop
Described in perlinterp.
XCPT_CATCH
Introduces a catch block. See "Exception Handling" in perlguts.
XCPT_RETHROW
Rethrows a previously caught exception. See "Exception Handling" in perlguts.
XCPT_RETHROW;
XCPT_TRY_END
Ends a try block. See "Exception Handling" in perlguts.
XCPT_TRY_START
Starts a try block. See "Exception Handling" in perlguts.
Also see "List of capability HAS_foo symbols".
DIRNAMLEN
This symbol, if defined, indicates to the C program that the length of directory entry names is provided by a d_namlen
field. Otherwise you need to do strlen()
on the d_name
field.
DOSUID
This symbol, if defined, indicates that the C program should check the script that it is executing for setuid/setgid bits, and attempt to emulate setuid/setgid on systems that have disabled setuid #! scripts because the kernel can't do it securely. It is up to the package designer to make sure that this emulation is done securely. Among other things, it should do an fstat on the script it just opened to make sure it really is a setuid/setgid script, it should make sure the arguments passed correspond exactly to the argument on the #! line, and it should not trust any subprocesses to which it must pass the filename rather than the file descriptor of the script to be executed.
EOF_NONBLOCK
This symbol, if defined, indicates to the C program that a read()
on a non-blocking file descriptor will return 0 on EOF
, and not the value held in RD_NODATA
(-1 usually, in that case!).
FCNTL_CAN_LOCK
This symbol, if defined, indicates that fcntl()
can be used for file locking. Normally on Unix systems this is defined. It may be undefined on VMS
.
FFLUSH_ALL
This symbol, if defined, tells that to flush all pending stdio output one must loop through all the stdio file handles stored in an array and fflush them. Note that if fflushNULL
is defined, fflushall will not even be probed for and will be left undefined.
FFLUSH_NULL
This symbol, if defined, tells that fflush(NULL)
correctly flushes all pending stdio output without side effects. In particular, on some platforms calling fflush(NULL)
*still* corrupts STDIN
if it is a pipe.
FILE_base
This macro is used to access the _base
field (or equivalent) of the FILE
structure pointed to by its argument. This macro will always be defined if USE_STDIO_BASE
is defined.
void * FILE_base(FILE * f)
FILE_bufsiz
This macro is used to determine the number of bytes in the I/O buffer pointed to by _base
field (or equivalent) of the FILE
structure pointed to its argument. This macro will always be defined if USE_STDIO_BASE
is defined.
Size_t FILE_bufsiz(FILE *f)
FILE_cnt
This macro is used to access the _cnt
field (or equivalent) of the FILE
structure pointed to by its argument. This macro will always be defined if USE_STDIO_PTR
is defined.
Size_t FILE_cnt(FILE * f)
FILE_ptr
This macro is used to access the _ptr
field (or equivalent) of the FILE
structure pointed to by its argument. This macro will always be defined if USE_STDIO_PTR
is defined.
void * FILE_ptr(FILE * f)
FLEXFILENAMES
This symbol, if defined, indicates that the system supports filenames longer than 14 characters.
HAS_DIR_DD_FD
This symbol, if defined, indicates that the the DIR
* dirstream structure contains a member variable named dd_fd
.
HAS_DUP2
This symbol, if defined, indicates that the dup2
routine is available to duplicate file descriptors.
HAS_DUP3
This symbol, if defined, indicates that the dup3
routine is available to duplicate file descriptors.
HAS_FAST_STDIO
This symbol, if defined, indicates that the "fast stdio" is available to manipulate the stdio buffers directly.
HAS_FCHDIR
This symbol, if defined, indicates that the fchdir
routine is available to change directory using a file descriptor.
HAS_FDCLOSE
This symbol, if defined, indicates that the fdclose
routine is available to free a FILE
structure without closing the underlying file descriptor. This function appeared in FreeBSD
10.2.
HAS_FPATHCONF
This symbol, if defined, indicates that pathconf()
is available to determine file-system related limits and options associated with a given open file descriptor.
HAS_FSTATFS
This symbol, if defined, indicates that the fstatfs
routine is available to stat filesystems by file descriptors.
HAS_FSTATVFS
This symbol, if defined, indicates that the fstatvfs
routine is available to stat filesystems by file descriptors.
HAS_GETFSSTAT
This symbol, if defined, indicates that the getfsstat
routine is available to stat filesystems in bulk.
HAS_GETMNT
This symbol, if defined, indicates that the getmnt
routine is available to get filesystem mount info by filename.
HAS_GETMNTENT
This symbol, if defined, indicates that the getmntent
routine is available to iterate through mounted file systems to get their info.
HAS_HASMNTOPT
This symbol, if defined, indicates that the hasmntopt
routine is available to query the mount options of file systems.
HAS_LSEEK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the lseek()
function. Otherwise, it is up to the program to supply one. A good guess is
extern off_t lseek(int, off_t, int);
HAS_MKDIR
This symbol, if defined, indicates that the mkdir
routine is available to create directories. Otherwise you should fork off a new process to exec /bin/mkdir.
HAS_OPEN3
This manifest constant lets the C program know that the three argument form of open(2)
is available.
HAS_POLL
This symbol, if defined, indicates that the poll
routine is available to poll
active file descriptors. Please check I_POLL
and I_SYS_POLL
to know which header should be included as well.
HAS_READDIR
This symbol, if defined, indicates that the readdir
routine is available to read directory entries. You may have to include dirent.h. See "I_DIRENT"
.
HAS_READDIR64_R
This symbol, if defined, indicates that the readdir64_r
routine is available to readdir64 re-entrantly.
HAS_REWINDDIR
This symbol, if defined, indicates that the rewinddir
routine is available. You may have to include dirent.h. See "I_DIRENT"
.
HAS_RMDIR
This symbol, if defined, indicates that the rmdir
routine is available to remove directories. Otherwise you should fork off a new process to exec /bin/rmdir.
HAS_SEEKDIR
This symbol, if defined, indicates that the seekdir
routine is available. You may have to include dirent.h. See "I_DIRENT"
.
HAS_SELECT
This symbol, if defined, indicates that the select
routine is available to select
active file descriptors. If the timeout field is used, sys/time.h may need to be included.
HAS_SETVBUF
This symbol, if defined, indicates that the setvbuf
routine is available to change buffering on an open stdio stream. to a line-buffered mode.
HAS_STDIO_STREAM_ARRAY
This symbol, if defined, tells that there is an array holding the stdio streams.
HAS_STRUCT_FS_DATA
This symbol, if defined, indicates that the struct fs_data
to do statfs()
is supported.
HAS_STRUCT_STATFS
This symbol, if defined, indicates that the struct statfs
to do statfs()
is supported.
HAS_STRUCT_STATFS_F_FLAGS
This symbol, if defined, indicates that the struct statfs
does have the f_flags
member containing the mount flags of the filesystem containing the file. This kind of struct statfs
is coming from sys/mount.h (BSD
4.3), not from sys/statfs.h (SYSV
). Older BSDs
(like Ultrix) do not have statfs()
and struct statfs
, they have ustat()
and getmnt()
with struct ustat
and struct fs_data
.
HAS_TELLDIR
This symbol, if defined, indicates that the telldir
routine is available. You may have to include dirent.h. See "I_DIRENT"
.
HAS_USTAT
This symbol, if defined, indicates that the ustat
system call is available to query file system statistics by dev_t
.
I_FCNTL
This manifest constant tells the C program to include fcntl.h.
#ifdef I_FCNTL #include <fcntl.h> #endif
I_SYS_DIR
This symbol, if defined, indicates to the C program that it should include sys/dir.h.
#ifdef I_SYS_DIR #include <sys_dir.h> #endif
I_SYS_FILE
This symbol, if defined, indicates to the C program that it should include sys/file.h to get definition of R_OK
and friends.
#ifdef I_SYS_FILE #include <sys_file.h> #endif
I_SYS_NDIR
This symbol, if defined, indicates to the C program that it should include sys/ndir.h.
#ifdef I_SYS_NDIR #include <sys_ndir.h> #endif
I_SYS_STATFS
This symbol, if defined, indicates that sys/statfs.h exists.
#ifdef I_SYS_STATFS #include <sys_statfs.h> #endif
RD_NODATA
This symbol holds the return code from read()
when no data is present on the non-blocking file descriptor. Be careful! If EOF_NONBLOCK
is not defined, then you can't distinguish between no data and EOF
by issuing a read()
. You'll have to find another way to tell for sure!
READDIR64_R_PROTO
This symbol encodes the prototype of readdir64_r
. It is zero if d_readdir64_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_readdir64_r
is defined.
STDCHAR
This symbol is defined to be the type of char used in stdio.h. It has the values "unsigned char" or "char".
STDIO_PTR_LVAL_NOCHANGE_CNT
This symbol is defined if using the FILE_ptr
macro as an lvalue to increase the pointer by n leaves File_cnt(fp)
unchanged.
STDIO_PTR_LVAL_SETS_CNT
This symbol is defined if using the FILE_ptr
macro as an lvalue to increase the pointer by n has the side effect of decreasing the value of File_cnt(fp)
by n.
STDIO_STREAM_ARRAY
This symbol tells the name of the array holding the stdio streams. Usual values include _iob
, __iob
, and __sF
.
ST_INO_SIGN
This symbol holds the signedness of struct stat
's st_ino
. 1 for unsigned, -1 for signed.
VAL_EAGAIN
This symbol holds the errno error code set by read()
when no data was present on the non-blocking file descriptor.
VAL_O_NONBLOCK
This symbol is to be used during open()
or fcntl(F_SETFL)
to turn on non-blocking I/O for the file descriptor. Note that there is no way back, i.e. you cannot turn it blocking again this way. If you wish to alternatively switch between blocking and non-blocking, use the ioctl(FIOSNBIO)
call instead, but that is not supported by all devices.
Also "List of capability HAS_foo symbols" lists capabilities that arent in this section. For example HAS_ASINH
, for the hyperbolic sine function.
CASTFLAGS
This symbol contains flags that say what difficulties the compiler has casting odd floating values to unsigned long:
0 = ok 1 = couldn't cast < 0 2 = couldn't cast >= 0x80000000 4 = couldn't cast in argument expression list
CASTNEGFLOAT
This symbol is defined if the C compiler can cast negative numbers to unsigned longs, ints and shorts.
DOUBLE_HAS_SUBNORMALS
This symbol, if defined, indicates that the double has the subnormals (denormals).
DOUBLEINFBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes for the double precision infinity.
DOUBLEKIND
DOUBLEKIND
will be one of DOUBLE_IS_IEEE_754_32_BIT_LITTLE_ENDIAN
DOUBLE_IS_IEEE_754_32_BIT_BIG_ENDIAN
DOUBLE_IS_IEEE_754_64_BIT_LITTLE_ENDIAN
DOUBLE_IS_IEEE_754_64_BIT_BIG_ENDIAN
DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIAN
DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIAN
DOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_LE_BE
DOUBLE_IS_IEEE_754_64_BIT_MIXED_ENDIAN_BE_LE
DOUBLE_IS_VAX_F_FLOAT
DOUBLE_IS_VAX_D_FLOAT
DOUBLE_IS_VAX_G_FLOAT
DOUBLE_IS_IBM_SINGLE_32_BIT
DOUBLE_IS_IBM_DOUBLE_64_BIT
DOUBLE_IS_CRAY_SINGLE_64_BIT
DOUBLE_IS_UNKNOWN_FORMAT
DOUBLEMANTBITS
This symbol, if defined, tells how many mantissa bits there are in double precision floating point format. Note that this is usually DBL_MANT_DIG
minus one, since with the standard IEEE
754 formats DBL_MANT_DIG
includes the implicit bit, which doesn't really exist.
DOUBLENANBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes (0xHH) for the double precision not-a-number.
DOUBLESIZE
This symbol contains the size of a double, so that the C preprocessor can make decisions based on it.
DOUBLE_STYLE_CRAY
This symbol, if defined, indicates that the double is the 64-bit CRAY
mainframe format.
DOUBLE_STYLE_IBM
This symbol, if defined, indicates that the double is the 64-bit IBM
mainframe format.
DOUBLE_STYLE_VAX
This symbol, if defined, indicates that the double is the 64-bit VAX
format D or G.
HAS_ATOLF
This symbol, if defined, indicates that the atolf
routine is available to convert strings into long doubles.
HAS_CLASS
This symbol, if defined, indicates that the class
routine is available to classify doubles. Available for example in AIX
. The returned values are defined in float.h and are:
FP_PLUS_NORM Positive normalized, nonzero FP_MINUS_NORM Negative normalized, nonzero FP_PLUS_DENORM Positive denormalized, nonzero FP_MINUS_DENORM Negative denormalized, nonzero FP_PLUS_ZERO +0.0 FP_MINUS_ZERO -0.0 FP_PLUS_INF +INF FP_MINUS_INF -INF FP_NANS Signaling Not a Number (NaNS) FP_NANQ Quiet Not a Number (NaNQ)
HAS_FINITE
This symbol, if defined, indicates that the finite
routine is available to check whether a double is finite
(non-infinity non-NaN).
HAS_FINITEL
This symbol, if defined, indicates that the finitel
routine is available to check whether a long double is finite (non-infinity non-NaN).
HAS_FPCLASS
This symbol, if defined, indicates that the fpclass
routine is available to classify doubles. Available for example in Solaris/SVR4
. The returned values are defined in ieeefp.h and are:
FP_SNAN signaling NaN FP_QNAN quiet NaN FP_NINF negative infinity FP_PINF positive infinity FP_NDENORM negative denormalized non-zero FP_PDENORM positive denormalized non-zero FP_NZERO negative zero FP_PZERO positive zero FP_NNORM negative normalized non-zero FP_PNORM positive normalized non-zero
HAS_FPCLASSIFY
This symbol, if defined, indicates that the fpclassify
routine is available to classify doubles. Available for example in HP-UX. The returned values are defined in math.h and are
FP_NORMAL Normalized FP_ZERO Zero FP_INFINITE Infinity FP_SUBNORMAL Denormalized FP_NAN NaN
HAS_FPCLASSL
This symbol, if defined, indicates that the fpclassl
routine is available to classify long doubles. Available for example in IRIX
. The returned values are defined in ieeefp.h and are:
FP_SNAN signaling NaN FP_QNAN quiet NaN FP_NINF negative infinity FP_PINF positive infinity FP_NDENORM negative denormalized non-zero FP_PDENORM positive denormalized non-zero FP_NZERO negative zero FP_PZERO positive zero FP_NNORM negative normalized non-zero FP_PNORM positive normalized non-zero
HAS_FPGETROUND
This symbol, if defined, indicates that the fpgetround
routine is available to get the floating point rounding mode.
HAS_FP_CLASS
This symbol, if defined, indicates that the fp_class
routine is available to classify doubles. Available for example in Digital UNIX
. The returned values are defined in math.h and are:
FP_SNAN Signaling NaN (Not-a-Number) FP_QNAN Quiet NaN (Not-a-Number) FP_POS_INF +infinity FP_NEG_INF -infinity FP_POS_NORM Positive normalized FP_NEG_NORM Negative normalized FP_POS_DENORM Positive denormalized FP_NEG_DENORM Negative denormalized FP_POS_ZERO +0.0 (positive zero) FP_NEG_ZERO -0.0 (negative zero)
HAS_FP_CLASSIFY
This symbol, if defined, indicates that the fp_classify
routine is available to classify doubles. The values are defined in math.h
FP_NORMAL Normalized FP_ZERO Zero FP_INFINITE Infinity FP_SUBNORMAL Denormalized FP_NAN NaN
HAS_FP_CLASSL
This symbol, if defined, indicates that the fp_classl
routine is available to classify long doubles. Available for example in Digital UNIX
. See for possible values HAS_FP_CLASS
.
HAS_FREXPL
This symbol, if defined, indicates that the frexpl
routine is available to break a long double floating-point number into a normalized fraction and an integral power of 2.
HAS_ILOGB
This symbol, if defined, indicates that the ilogb
routine is available to get integer exponent of a floating-point value.
HAS_ISFINITE
This symbol, if defined, indicates that the isfinite
routine is available to check whether a double is finite (non-infinity non-NaN).
HAS_ISFINITEL
This symbol, if defined, indicates that the isfinitel
routine is available to check whether a long double is finite. (non-infinity non-NaN).
HAS_ISINF
This symbol, if defined, indicates that the isinf
routine is available to check whether a double is an infinity.
HAS_ISINFL
This symbol, if defined, indicates that the isinfl
routine is available to check whether a long double is an infinity.
HAS_ISNAN
This symbol, if defined, indicates that the isnan
routine is available to check whether a double is a NaN.
HAS_ISNANL
This symbol, if defined, indicates that the isnanl
routine is available to check whether a long double is a NaN.
HAS_ISNORMAL
This symbol, if defined, indicates that the isnormal
routine is available to check whether a double is normal (non-zero normalized).
HAS_J0
This symbol, if defined, indicates to the C program that the j0()
function is available for Bessel functions of the first kind of the order zero, for doubles.
HAS_J0L
This symbol, if defined, indicates to the C program that the j0l()
function is available for Bessel functions of the first kind of the order zero, for long doubles.
HAS_LDBL_DIG
This symbol, if defined, indicates that this system's float.h or limits.h defines the symbol LDBL_DIG
, which is the number of significant digits in a long double precision number. Unlike for DBL_DIG
, there's no good guess for LDBL_DIG
if it is undefined.
HAS_LDEXPL
This symbol, if defined, indicates that the ldexpl
routine is available to shift a long double floating-point number by an integral power of 2.
HAS_LLRINT
This symbol, if defined, indicates that the llrint
routine is available to return the long long value closest to a double (according to the current rounding mode).
HAS_LLRINTL
This symbol, if defined, indicates that the llrintl
routine is available to return the long long value closest to a long double (according to the current rounding mode).
HAS_LLROUNDL
This symbol, if defined, indicates that the llroundl
routine is available to return the nearest long long value away from zero of the long double argument value.
HAS_LRINT
This symbol, if defined, indicates that the lrint
routine is available to return the integral value closest to a double (according to the current rounding mode).
HAS_LRINTL
This symbol, if defined, indicates that the lrintl
routine is available to return the integral value closest to a long double (according to the current rounding mode).
HAS_LROUNDL
This symbol, if defined, indicates that the lroundl
routine is available to return the nearest integral value away from zero of the long double argument value.
HAS_MODFL
This symbol, if defined, indicates that the modfl
routine is available to split a long double x into a fractional part f and an integer part i such that |f| < 1.0 and (f + i) = x.
HAS_NEXTTOWARD
This symbol, if defined, indicates that the nexttoward
routine is available to return the next machine representable long double from x in direction y.
HAS_REMAINDER
This symbol, if defined, indicates that the remainder
routine is available to return the floating-point remainder
.
HAS_SCALBN
This symbol, if defined, indicates that the scalbn
routine is available to multiply floating-point number by integral power of radix.
HAS_SIGNBIT
This symbol, if defined, indicates that the signbit
routine is available to check if the given number has the sign bit set. This should include correct testing of -0.0. This will only be set if the signbit()
routine is safe to use with the NV type used internally in perl. Users should call Perl_signbit()
, which will be #defined to the system's signbit()
function or macro if this symbol is defined.
HAS_SQRTL
This symbol, if defined, indicates that the sqrtl
routine is available to do long double square roots.
HAS_STRTOD_L
This symbol, if defined, indicates that the strtod_l
routine is available to convert strings to long doubles.
HAS_STRTOLD
This symbol, if defined, indicates that the strtold
routine is available to convert strings to long doubles.
HAS_STRTOLD_L
This symbol, if defined, indicates that the strtold_l
routine is available to convert strings to long doubles.
HAS_TRUNC
This symbol, if defined, indicates that the trunc
routine is available to round doubles towards zero.
HAS_UNORDERED
This symbol, if defined, indicates that the unordered
routine is available to check whether two doubles are unordered
(effectively: whether either of them is NaN)
I_FENV
This symbol, if defined, indicates to the C program that it should include fenv.h to get the floating point environment definitions.
#ifdef I_FENV #include <fenv.h> #endif
I_QUADMATH
This symbol, if defined, indicates that quadmath.h exists and should be included.
#ifdef I_QUADMATH #include <quadmath.h> #endif
LONGDBLINFBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes for the long double precision infinity.
LONGDBLMANTBITS
This symbol, if defined, tells how many mantissa bits there are in long double precision floating point format. Note that this can be LDBL_MANT_DIG
minus one, since LDBL_MANT_DIG
can include the IEEE
754 implicit bit. The common x86-style 80-bit long double does not have an implicit bit.
LONGDBLNANBYTES
This symbol, if defined, is a comma-separated list of hexadecimal bytes (0xHH) for the long double precision not-a-number.
LONG_DOUBLEKIND
LONG_DOUBLEKIND
will be one of LONG_DOUBLE_IS_DOUBLE
LONG_DOUBLE_IS_IEEE_754_128_BIT_LITTLE_ENDIAN
LONG_DOUBLE_IS_IEEE_754_128_BIT_BIG_ENDIAN
LONG_DOUBLE_IS_X86_80_BIT_LITTLE_ENDIAN
LONG_DOUBLE_IS_X86_80_BIT_BIG_ENDIAN
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_LE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_BE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LE_BE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BE_LE
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_LITTLE_ENDIAN
LONG_DOUBLE_IS_DOUBLEDOUBLE_128_BIT_BIG_ENDIAN
LONG_DOUBLE_IS_VAX_H_FLOAT
LONG_DOUBLE_IS_UNKNOWN_FORMAT
It is only defined if the system supports long doubles.
LONG_DOUBLESIZE
This symbol contains the size of a long double, so that the C preprocessor can make decisions based on it. It is only defined if the system supports long doubles. Note that this is sizeof(long double)
, which may include unused bytes.
LONG_DOUBLE_STYLE_IEEE
This symbol, if defined, indicates that the long double is any of the IEEE
754 style long doubles: LONG_DOUBLE_STYLE_IEEE_STD
, LONG_DOUBLE_STYLE_IEEE_EXTENDED
, LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE
.
LONG_DOUBLE_STYLE_IEEE_DOUBLEDOUBLE
This symbol, if defined, indicates that the long double is the 128-bit double-double.
LONG_DOUBLE_STYLE_IEEE_EXTENDED
This symbol, if defined, indicates that the long double is the 80-bit IEEE
754. Note that despite the 'extended' this is less than the 'std', since this is an extension of the double precision.
LONG_DOUBLE_STYLE_IEEE_STD
This symbol, if defined, indicates that the long double is the 128-bit IEEE
754.
LONG_DOUBLE_STYLE_VAX
This symbol, if defined, indicates that the long double is the 128-bit VAX
format H.
NV
Described in perlguts.
NVMANTBITS
This symbol, if defined, tells how many mantissa bits (not including implicit bit) there are in a Perl NV. This depends on which floating point type was chosen.
NV_OVERFLOWS_INTEGERS_AT
This symbol gives the largest integer value that NVs can hold. This value + 1.0 cannot be stored accurately. It is expressed as constant floating point expression to reduce the chance of decimal/binary conversion issues. If it can not be determined, the value 0 is given.
NV_PRESERVES_UV
This symbol, if defined, indicates that a variable of type NVTYPE
can preserve all the bits of a variable of type UVTYPE
.
NV_PRESERVES_UV_BITS
This symbol contains the number of bits a variable of type NVTYPE
can preserve of a variable of type UVTYPE
.
NVSIZE
This symbol contains the sizeof(NV)
. Note that some floating point formats have unused bytes. The most notable example is the x86* 80-bit extended precision which comes in byte sizes of 12 and 16 (for 32 and 64 bit platforms, respectively), but which only uses 10 bytes. Perl compiled with -Duselongdouble
on x86* is like this.
This section contains configuration information not otherwise found in the more specialized sections of this document. At the end is a list of #defines
whose name should be enough to tell you what they do, and a list of #defines which tell you if you need to #include
files to get the corresponding functionality.
BYTEORDER
This symbol holds the hexadecimal constant defined in byteorder, in a UV, i.e. 0x1234 or 0x4321 or 0x12345678, etc... If the compiler supports cross-compiling or multiple-architecture binaries, use compiler-defined macros to determine the byte order.
CHARBITS
This symbol contains the size of a char, so that the C preprocessor can make decisions based on it.
DB_VERSION_MAJOR_CFG
This symbol, if defined, defines the major version number of Berkeley DB found in the db.h header when Perl was configured.
DB_VERSION_MINOR_CFG
This symbol, if defined, defines the minor version number of Berkeley DB found in the db.h header when Perl was configured. For DB version 1 this is always 0.
DB_VERSION_PATCH_CFG
This symbol, if defined, defines the patch version number of Berkeley DB found in the db.h header when Perl was configured. For DB version 1 this is always 0.
DEFAULT_INC_EXCLUDES_DOT
This symbol, if defined, removes the legacy default behavior of including '.' at the end of @INC
.
DLSYM_NEEDS_UNDERSCORE
This symbol, if defined, indicates that we need to prepend an underscore to the symbol name before calling dlsym()
. This only makes sense if you *have* dlsym, which we will presume is the case if you're using dl_dlopen.xs.
HAS_GETHOSTNAME
This symbol, if defined, indicates that the C program may use the gethostname()
routine to derive the host name. See also "HAS_UNAME"
and "PHOSTNAME"
.
HAS_GNULIBC
This symbol, if defined, indicates to the C program that the GNU
C library is being used. A better check is to use the __GLIBC__
and __GLIBC_MINOR__
symbols supplied with glibc.
HAS_LGAMMA
This symbol, if defined, indicates that the lgamma
routine is available to do the log gamma function. See also "HAS_TGAMMA"
and "HAS_LGAMMA_R"
.
HAS_LGAMMA_R
This symbol, if defined, indicates that the lgamma_r
routine is available to do the log gamma function without using the global signgam variable.
HAS_NON_INT_BITFIELDS
This symbol, if defined, indicates that the C compiler accepts, without error or warning, struct bitfields
that are declared with sizes other than plain 'int'; for example 'unsigned char' is accepted.
HAS_PRCTL_SET_NAME
This symbol, if defined, indicates that the prctl routine is available to set process title and supports PR_SET_NAME
.
HAS_PROCSELFEXE
This symbol is defined if PROCSELFEXE_PATH
is a symlink to the absolute pathname of the executing program.
HAS_PSEUDOFORK
This symbol, if defined, indicates that an emulation of the fork routine is available.
HAS_REGCOMP
This symbol, if defined, indicates that the regcomp()
routine is available to do some regular pattern matching (usually on POSIX
.2 conforming systems).
HAS_SETPGID
This symbol, if defined, indicates that the setpgid(pid, gpid)
routine is available to set process group ID.
HAS_SIGSETJMP
This variable indicates to the C program that the sigsetjmp()
routine is available to save the calling process's registers and stack environment for later use by siglongjmp()
, and to optionally save the process's signal mask. See "Sigjmp_buf"
, "Sigsetjmp"
, and "Siglongjmp"
.
HAS_TGAMMA
This symbol, if defined, indicates that the tgamma
routine is available to do the gamma function. See also "HAS_LGAMMA"
.
HAS_UNAME
This symbol, if defined, indicates that the C program may use the uname()
routine to derive the host name. See also "HAS_GETHOSTNAME"
and "PHOSTNAME"
.
HAS_UNION_SEMUN
This symbol, if defined, indicates that the union semun
is defined by including sys/sem.h. If not, the user code probably needs to define it as:
union semun { int val; struct semid_ds *buf; unsigned short *array; }
I_DIRENT
This symbol, if defined, indicates to the C program that it should include dirent.h. Using this symbol also triggers the definition of the Direntry_t
define which ends up being 'struct dirent
' or 'struct direct
' depending on the availability of dirent.h.
#ifdef I_DIRENT #include <dirent.h> #endif
I_POLL
This symbol, if defined, indicates that poll.h exists and should be included. (see also "HAS_POLL"
)
#ifdef I_POLL #include <poll.h> #endif
I_SYS_RESOURCE
This symbol, if defined, indicates to the C program that it should include sys/resource.h.
#ifdef I_SYS_RESOURCE #include <sys_resource.h> #endif
LIBM_LIB_VERSION
This symbol, if defined, indicates that libm exports _LIB_VERSION
and that math.h defines the enum to manipulate it.
NEED_VA_COPY
This symbol, if defined, indicates that the system stores the variable argument list datatype, va_list
, in a format that cannot be copied by simple assignment, so that some other means must be used when copying is required. As such systems vary in their provision (or non-provision) of copying mechanisms, handy.h defines a platform- independent macro, Perl_va_copy(src, dst)
, to do the job.
OSNAME
This symbol contains the name of the operating system, as determined by Configure. You shouldn't rely on it too much; the specific feature tests from Configure are generally more reliable.
OSVERS
This symbol contains the version of the operating system, as determined by Configure. You shouldn't rely on it too much; the specific feature tests from Configure are generally more reliable.
PHOSTNAME
This symbol, if defined, indicates the command to feed to the popen()
routine to derive the host name. See also "HAS_GETHOSTNAME"
and "HAS_UNAME"
. Note that the command uses a fully qualified path, so that it is safe even if used by a process with super-user privileges.
PROCSELFEXE_PATH
If HAS_PROCSELFEXE
is defined this symbol is the filename of the symbolic link pointing to the absolute pathname of the executing program.
PTRSIZE
This symbol contains the size of a pointer, so that the C preprocessor can make decisions based on it. It will be sizeof(void *)
if the compiler supports (void *); otherwise it will be sizeof(char *)
.
RANDBITS
This symbol indicates how many bits are produced by the function used to generate normalized random numbers. Values include 15, 16, 31, and 48.
SELECT_MIN_BITS
This symbol holds the minimum number of bits operated by select. That is, if you do select(n, ...)
, how many bits at least will be cleared in the masks if some activity is detected. Usually this is either n or 32*ceil(n/32)
, especially many little-endians do the latter. This is only useful if you have select()
, naturally.
SETUID_SCRIPTS_ARE_SECURE_NOW
This symbol, if defined, indicates that the bug that prevents setuid scripts from being secure is not present in this kernel.
ST_DEV_SIGN
This symbol holds the signedness of struct stat
's st_dev
. 1 for unsigned, -1 for signed.
HAS_foo
symbols
This is a list of those symbols that dont appear elsewhere in ths document that indicate if the current platform has a certain capability. Their names all begin with HAS_
. Only those symbols whose capability is directly derived from the name are listed here. All others have their meaning expanded out elsewhere in this document. This (relatively) compact list is because we think that the expansion would add little or no value and take up a lot of space (because there are so many). If you think certain ones should be expanded, send email to perl5-porters@perl.org.
Each symbol here will be #define
d if and only if the platform has the capability. If you need more detail, see the corresponding entry in config.h. For convenience, the list is split so that the ones that indicate there is a reentrant version of a capability are listed separately
HAS_ACCEPT4
,
HAS_ACCESS
,
HAS_ACCESSX
,
HAS_ACOSH
,
HAS_AINTL
,
HAS_ALARM
,
HAS_ASINH
,
HAS_ATANH
,
HAS_ATOLL
,
HAS_CBRT
,
HAS_CHOWN
,
HAS_CHROOT
,
HAS_CHSIZE
,
HAS_CLEARENV
,
HAS_COPYSIGN
,
HAS_COPYSIGNL
,
HAS_CRYPT
,
HAS_CTERMID
,
HAS_CUSERID
,
HAS_DIRFD
,
HAS_DLADDR
,
HAS_DLERROR
,
HAS_EACCESS
,
HAS_ENDHOSTENT
,
HAS_ENDNETENT
,
HAS_ENDPROTOENT
,
HAS_ENDSERVENT
,
HAS_ERF
,
HAS_ERFC
,
HAS_EXP2
,
HAS_EXPM1
,
HAS_FCHMOD
,
HAS_FCHMODAT
,
HAS_FCHOWN
,
HAS_FDIM
,
HAS_FD_SET
,
HAS_FEGETROUND
,
HAS_FFS
,
HAS_FFSL
,
HAS_FGETPOS
,
HAS_FLOCK
,
HAS_FMA
,
HAS_FMAX
,
HAS_FMIN
,
HAS_FORK
,
HAS_FSEEKO
,
HAS_FSETPOS
,
HAS_FSYNC
,
HAS_FTELLO
,
HAS_GAI_STRERROR
,
HAS_GETADDRINFO
,
HAS_GETCWD
,
HAS_GETESPWNAM
,
HAS_GETGROUPS
,
HAS_GETHOSTBYADDR
,
HAS_GETHOSTBYNAME
,
HAS_GETHOSTENT
,
HAS_GETLOGIN
,
HAS_GETNAMEINFO
,
HAS_GETNETBYADDR
,
HAS_GETNETBYNAME
,
HAS_GETNETENT
,
HAS_GETPAGESIZE
,
HAS_GETPGID
,
HAS_GETPGRP
,
HAS_GETPGRP2
,
HAS_GETPPID
,
HAS_GETPRIORITY
,
HAS_GETPROTOBYNAME
,
HAS_GETPROTOBYNUMBER
,
HAS_GETPROTOENT
,
HAS_GETPRPWNAM
,
HAS_GETSERVBYNAME
,
HAS_GETSERVBYPORT
,
HAS_GETSERVENT
,
HAS_GETSPNAM
,
HAS_HTONL
,
HAS_HTONS
,
HAS_HYPOT
,
HAS_ILOGBL
,
HAS_INETNTOP
,
HAS_INETPTON
,
HAS_INET_ATON
,
HAS_IPV6_MREQ
,
HAS_IPV6_MREQ_SOURCE
,
HAS_IP_MREQ
,
HAS_IP_MREQ_SOURCE
,
HAS_ISASCII
,
HAS_ISBLANK
,
HAS_ISLESS
,
HAS_KILLPG
,
HAS_LCHOWN
,
HAS_LINK
,
HAS_LINKAT
,
HAS_LLROUND
,
HAS_LOCKF
,
HAS_LOG1P
,
HAS_LOG2
,
HAS_LOGB
,
HAS_LROUND
,
HAS_LSTAT
,
HAS_MADVISE
,
HAS_MBLEN
,
HAS_MBRLEN
,
HAS_MBRTOWC
,
HAS_MBSTOWCS
,
HAS_MBTOWC
,
HAS_MEMMEM
,
HAS_MEMRCHR
,
HAS_MKDTEMP
,
HAS_MKFIFO
,
HAS_MKOSTEMP
,
HAS_MKSTEMP
,
HAS_MKSTEMPS
,
HAS_MMAP
,
HAS_MPROTECT
,
HAS_MSG
,
HAS_MSYNC
,
HAS_MUNMAP
,
HAS_NEARBYINT
,
HAS_NEXTAFTER
,
HAS_NICE
,
HAS_NTOHL
,
HAS_NTOHS
,
HAS_PATHCONF
,
HAS_PAUSE
,
HAS_PHOSTNAME
,
HAS_PIPE
,
HAS_PIPE2
,
HAS_PRCTL
,
HAS_PTRDIFF_T
,
HAS_READLINK
,
HAS_READV
,
HAS_RECVMSG
,
HAS_REMQUO
,
HAS_RENAME
,
HAS_RENAMEAT
,
HAS_RINT
,
HAS_ROUND
,
HAS_SCALBNL
,
HAS_SEM
,
HAS_SENDMSG
,
HAS_SETEGID
,
HAS_SETEUID
,
HAS_SETGROUPS
,
HAS_SETHOSTENT
,
HAS_SETLINEBUF
,
HAS_SETNETENT
,
HAS_SETPGRP
,
HAS_SETPGRP2
,
HAS_SETPRIORITY
,
HAS_SETPROCTITLE
,
HAS_SETPROTOENT
,
HAS_SETREGID
,
HAS_SETRESGID
,
HAS_SETRESUID
,
HAS_SETREUID
,
HAS_SETRGID
,
HAS_SETRUID
,
HAS_SETSERVENT
,
HAS_SETSID
,
HAS_SHM
,
HAS_SIGACTION
,
HAS_SIGPROCMASK
,
HAS_SIN6_SCOPE_ID
,
HAS_SNPRINTF
,
HAS_STAT
,
HAS_STRCOLL
,
HAS_STRERROR_L
,
HAS_STRLCAT
,
HAS_STRLCPY
,
HAS_STRNLEN
,
HAS_STRTOD
,
HAS_STRTOL
,
HAS_STRTOLL
,
HAS_STRTOQ
,
HAS_STRTOUL
,
HAS_STRTOULL
,
HAS_STRTOUQ
,
HAS_STRXFRM
,
HAS_STRXFRM_L
,
HAS_SYMLINK
,
HAS_SYSCALL
,
HAS_SYSCONF
,
HAS_SYSTEM
,
HAS_SYS_ERRLIST
,
HAS_TCGETPGRP
,
HAS_TCSETPGRP
,
HAS_TOWLOWER
,
HAS_TOWUPPER
,
HAS_TRUNCATE
,
HAS_TRUNCL
,
HAS_UALARM
,
HAS_UMASK
,
HAS_UNLINKAT
,
HAS_UNSETENV
,
HAS_VFORK
,
HAS_VSNPRINTF
,
HAS_WAIT4
,
HAS_WAITPID
,
HAS_WCRTOMB
,
HAS_WCSCMP
,
HAS_WCSTOMBS
,
HAS_WCSXFRM
,
HAS_WCTOMB
,
HAS_WRITEV
,
HAS__FWALK
And, the reentrant capabilities:
HAS_CRYPT_R
,
HAS_CTERMID_R
,
HAS_DRAND48_R
,
HAS_ENDHOSTENT_R
,
HAS_ENDNETENT_R
,
HAS_ENDPROTOENT_R
,
HAS_ENDSERVENT_R
,
HAS_GETGRGID_R
,
HAS_GETGRNAM_R
,
HAS_GETHOSTBYADDR_R
,
HAS_GETHOSTBYNAME_R
,
HAS_GETHOSTENT_R
,
HAS_GETLOGIN_R
,
HAS_GETNETBYADDR_R
,
HAS_GETNETBYNAME_R
,
HAS_GETNETENT_R
,
HAS_GETPROTOBYNAME_R
,
HAS_GETPROTOBYNUMBER_R
,
HAS_GETPROTOENT_R
,
HAS_GETPWNAM_R
,
HAS_GETPWUID_R
,
HAS_GETSERVBYNAME_R
,
HAS_GETSERVBYPORT_R
,
HAS_GETSERVENT_R
,
HAS_GETSPNAM_R
,
HAS_RANDOM_R
,
HAS_READDIR_R
,
HAS_SETHOSTENT_R
,
HAS_SETNETENT_R
,
HAS_SETPROTOENT_R
,
HAS_SETSERVENT_R
,
HAS_SRAND48_R
,
HAS_SRANDOM_R
,
HAS_STRERROR_R
,
HAS_TMPNAM_R
,
HAS_TTYNAME_R
Example usage:
#ifdef HAS_STRNLEN use strnlen() #else use an alternative implementation #endif
#include
needed symbols
This list contains symbols that indicate if certain #include
files are present on the platform. If your code accesses the functionality that one of these is for, you will need to #include
it if the symbol on this list is #define
d. For more detail, see the corresponding entry in config.h.
I_ARPA_INET
,
I_BFD
,
I_CRYPT
,
I_DBM
,
I_DLFCN
,
I_EXECINFO
,
I_FP
,
I_FP_CLASS
,
I_GDBM
,
I_GDBMNDBM
,
I_GDBM_NDBM
,
I_GRP
,
I_IEEEFP
,
I_INTTYPES
,
I_LIBUTIL
,
I_MNTENT
,
I_NDBM
,
I_NETDB
,
I_NETINET_IN
,
I_NETINET_TCP
,
I_NET_ERRNO
,
I_PROT
,
I_PWD
,
I_RPCSVC_DBM
,
I_SGTTY
,
I_SHADOW
,
I_STDBOOL
,
I_STDINT
,
I_SUNMATH
,
I_SYSLOG
,
I_SYSMODE
,
I_SYSUIO
,
I_SYSUTSNAME
,
I_SYS_ACCESS
,
I_SYS_IOCTL
,
I_SYS_MOUNT
,
I_SYS_PARAM
,
I_SYS_POLL
,
I_SYS_SECURITY
,
I_SYS_SELECT
,
I_SYS_STAT
,
I_SYS_STATVFS
,
I_SYS_TIME
,
I_SYS_TIMES
,
I_SYS_TIME_KERNEL
,
I_SYS_TYPES
,
I_SYS_UN
,
I_SYS_VFS
,
I_SYS_WAIT
,
I_TERMIO
,
I_TERMIOS
,
I_UNISTD
,
I_USTAT
,
I_VFORK
,
I_WCHAR
,
I_WCTYPE
Example usage:
#ifdef I_WCHAR #include <wchar.h> #endif
These variables are global to an entire process. They are shared between all interpreters and all threads in a process. Any variables not documented here may be changed or removed without notice, so don't use them! If you feel you really do need to use an unlisted variable, first send email to perl5-porters@perl.org. It may be that someone there will point out a way to accomplish what you need without using an internal variable. But if not, you should get a go-ahead to document and then use the variable.
PL_check
Array, indexed by opcode, of functions that will be called for the "check" phase of optree building during compilation of Perl code. For most (but not all) types of op, once the op has been initially built and populated with child ops it will be filtered through the check function referenced by the appropriate element of this array. The new op is passed in as the sole argument to the check function, and the check function returns the completed op. The check function may (as the name suggests) check the op for validity and signal errors. It may also initialise or modify parts of the ops, or perform more radical surgery such as adding or removing child ops, or even throw the op away and return a different op in its place.
This array of function pointers is a convenient place to hook into the compilation process. An XS module can put its own custom check function in place of any of the standard ones, to influence the compilation of a particular type of op. However, a custom check function must never fully replace a standard check function (or even a custom check function from another module). A module modifying checking must instead wrap the preexisting check function. A custom check function must be selective about when to apply its custom behaviour. In the usual case where it decides not to do anything special with an op, it must chain the preexisting op function. Check functions are thus linked in a chain, with the core's base checker at the end.
For thread safety, modules should not write directly to this array. Instead, use the function "wrap_op_checker".
PL_keyword_plugin
NOTE: PL_keyword_plugin
is experimental and may change or be removed without notice.
Function pointer, pointing at a function used to handle extended keywords. The function should be declared as
int keyword_plugin_function(pTHX_ char *keyword_ptr, STRLEN keyword_len, OP **op_ptr)
The function is called from the tokeniser, whenever a possible keyword is seen. keyword_ptr
points at the word in the parser's input buffer, and keyword_len
gives its length; it is not null-terminated. The function is expected to examine the word, and possibly other state such as %^H, to decide whether it wants to handle it as an extended keyword. If it does not, the function should return KEYWORD_PLUGIN_DECLINE
, and the normal parser process will continue.
If the function wants to handle the keyword, it first must parse anything following the keyword that is part of the syntax introduced by the keyword. See "Lexer interface" for details.
When a keyword is being handled, the plugin function must build a tree of OP
structures, representing the code that was parsed. The root of the tree must be stored in *op_ptr
. The function then returns a constant indicating the syntactic role of the construct that it has parsed: KEYWORD_PLUGIN_STMT
if it is a complete statement, or KEYWORD_PLUGIN_EXPR
if it is an expression. Note that a statement construct cannot be used inside an expression (except via do BLOCK
and similar), and an expression is not a complete statement (it requires at least a terminating semicolon).
When a keyword is handled, the plugin function may also have (compile-time) side effects. It may modify %^H
, define functions, and so on. Typically, if side effects are the main purpose of a handler, it does not wish to generate any ops to be included in the normal compilation. In this case it is still required to supply an op tree, but it suffices to generate a single null op.
That's how the *PL_keyword_plugin
function needs to behave overall. Conventionally, however, one does not completely replace the existing handler function. Instead, take a copy of PL_keyword_plugin
before assigning your own function pointer to it. Your handler function should look for keywords that it is interested in and handle those. Where it is not interested, it should call the saved plugin function, passing on the arguments it received. Thus PL_keyword_plugin
actually points at a chain of handler functions, all of which have an opportunity to handle keywords, and only the last function in the chain (built into the Perl core) will normally return KEYWORD_PLUGIN_DECLINE
.
For thread safety, modules should not set this variable directly. Instead, use the function "wrap_keyword_plugin".
PL_phase
A value that indicates the current Perl interpreter's phase. Possible values include PERL_PHASE_CONSTRUCT
, PERL_PHASE_START
, PERL_PHASE_CHECK
, PERL_PHASE_INIT
, PERL_PHASE_RUN
, PERL_PHASE_END
, and PERL_PHASE_DESTRUCT
.
For example, the following determines whether the interpreter is in global destruction:
if (PL_phase == PERL_PHASE_DESTRUCT) { // we are in global destruction }
PL_phase
was introduced in Perl 5.14; in prior perls you can use PL_dirty
(boolean) to determine whether the interpreter is in global destruction. (Use of PL_dirty
is discouraged since 5.14.)
enum perl_phase PL_phase
A GV is a structure which corresponds to to a Perl typeglob, ie *foo. It is a structure that holds a pointer to a scalar, an array, a hash etc, corresponding to $foo, @foo, %foo.
GVs are usually found as values in stashes (symbol table hashes) where Perl stores its global variables.
A stash is a hash that contains all variables that are defined within a package. See "Stashes and Globs" in perlguts
amagic_call
Perform the overloaded (active magic) operation given by method
. method
is one of the values found in overload.h.
flags
affects how the operation is performed, as follows:
AMGf_noleft
left
is not to be used in this operation.
AMGf_noright
right
is not to be used in this operation.
AMGf_unary
The operation is done only on just one operand.
AMGf_assign
The operation changes one of the operands, e.g., $x += 1
SV* amagic_call(SV* left, SV* right, int method, int dir)
amagic_deref_call
Perform method
overloading dereferencing on ref
, returning the dereferenced result. method
must be one of the dereference operations given in overload.h.
If overloading is inactive on ref
, returns ref
itself.
SV * amagic_deref_call(SV *ref, int method)
gv_add_by_type
Make sure there is a slot of type type
in the GV gv
.
GV* gv_add_by_type(GV *gv, svtype type)
Gv_AMupdate
Recalculates overload magic in the package given by stash
.
Returns:
destructing
is true).int Gv_AMupdate(HV* stash, bool destructing)
gv_autoload4
Equivalent to "gv_autoload_pvn"
.
GV* gv_autoload4(HV* stash, const char* name, STRLEN len, I32 method)
gv_AVadd
gv_HVadd
gv_IOadd
gv_SVadd
Make sure there is a slot of the given type (AV, HV, IO, SV) in the GV gv
.
GV* gv_AVadd(GV *gv) GV* gv_HVadd(GV *gv) GV* gv_IOadd(GV* gv) GV* gv_SVadd(GV *gv)
gv_const_sv
If gv
is a typeglob whose subroutine entry is a constant sub eligible for inlining, or gv
is a placeholder reference that would be promoted to such a typeglob, then returns the value returned by the sub. Otherwise, returns NULL
.
SV* gv_const_sv(GV* gv)
gv_fetchfile
gv_fetchfile_flags
These return the debugger glob for the file (compiled by Perl) whose name is given by the name
parameter.
There are currently exactly two differences between these functions.
The name
parameter to gv_fetchfile
is a C string, meaning it is NUL
-terminated; whereas the name
parameter to gv_fetchfile_flags
is a Perl string, whose length (in bytes) is passed in via the namelen
parameter This means the name may contain embedded NUL
characters. namelen
doesn't exist in plain gv_fetchfile
).
The other difference is that gv_fetchfile_flags
has an extra flags
parameter, which is currently completely ignored, but allows for possible future extensions.
GV* gv_fetchfile (const char* name) GV* gv_fetchfile_flags(const char *const name, const STRLEN len, const U32 flags)
gv_fetchmeth
Like "gv_fetchmeth_pvn", but lacks a flags parameter.
GV* gv_fetchmeth(HV* stash, const char* name, STRLEN len, I32 level)
gv_fetchmethod_autoload
Returns the glob which contains the subroutine to call to invoke the method on the stash
. In fact in the presence of autoloading this may be the glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD
is already setup.
The third parameter of gv_fetchmethod_autoload
determines whether AUTOLOAD lookup is performed if the given method is not present: non-zero means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD. Calling gv_fetchmethod
is equivalent to calling gv_fetchmethod_autoload
with a non-zero autoload
parameter.
These functions grant "SUPER"
token as a prefix of the method name. Note that if you want to keep the returned glob for a long time, you need to check for it being "AUTOLOAD", since at the later time the call may load a different subroutine due to $AUTOLOAD
changing its value. Use the glob created as a side effect to do this.
These functions have the same side-effects as gv_fetchmeth
with level==0
. The warning against passing the GV returned by gv_fetchmeth
to call_sv
applies equally to these functions.
GV* gv_fetchmethod_autoload(HV* stash, const char* name, I32 autoload)
gv_fetchmeth_autoload
This is the old form of "gv_fetchmeth_pvn_autoload", which has no flags parameter.
GV* gv_fetchmeth_autoload(HV* stash, const char* name, STRLEN len, I32 level)
gv_fetchmeth_pv
Exactly like "gv_fetchmeth_pvn", but takes a nul-terminated string instead of a string/length pair.
GV* gv_fetchmeth_pv(HV* stash, const char* name, I32 level, U32 flags)
gv_fetchmeth_pvn
Returns the glob with the given name
and a defined subroutine or NULL
. The glob lives in the given stash
, or in the stashes accessible via @ISA
and UNIVERSAL::
.
The argument level
should be either 0 or -1. If level==0
, as a side-effect creates a glob with the given name
in the given stash
which in the case of success contains an alias for the subroutine, and sets up caching info for this glob.
The only significant values for flags
are GV_SUPER
, GV_NOUNIVERSAL
, and SVf_UTF8
.
GV_SUPER
indicates that we want to look up the method in the superclasses of the stash
.
GV_NOUNIVERSAL
indicates that we do not want to look up the method in the stash accessible by UNIVERSAL::
.
The GV returned from gv_fetchmeth
may be a method cache entry, which is not visible to Perl code. So when calling call_sv
, you should not use the GV directly; instead, you should use the method's CV, which can be obtained from the GV with the GvCV
macro.
GV* gv_fetchmeth_pvn(HV* stash, const char* name, STRLEN len, I32 level, U32 flags)
gv_fetchmeth_pvn_autoload
Same as gv_fetchmeth_pvn()
, but looks for autoloaded subroutines too. Returns a glob for the subroutine.
For an autoloaded subroutine without a GV, will create a GV even if level < 0
. For an autoloaded subroutine without a stub, GvCV()
of the result may be zero.
Currently, the only significant value for flags
is SVf_UTF8
.
GV* gv_fetchmeth_pvn_autoload(HV* stash, const char* name, STRLEN len, I32 level, U32 flags)
gv_fetchmeth_pv_autoload
Exactly like "gv_fetchmeth_pvn_autoload", but takes a nul-terminated string instead of a string/length pair.
GV* gv_fetchmeth_pv_autoload(HV* stash, const char* name, I32 level, U32 flags)
gv_fetchmeth_sv
Exactly like "gv_fetchmeth_pvn", but takes the name string in the form of an SV instead of a string/length pair.
GV* gv_fetchmeth_sv(HV* stash, SV* namesv, I32 level, U32 flags)
gv_fetchmeth_sv_autoload
Exactly like "gv_fetchmeth_pvn_autoload", but takes the name string in the form of an SV instead of a string/length pair.
GV* gv_fetchmeth_sv_autoload(HV* stash, SV* namesv, I32 level, U32 flags)
gv_fetchpv
gv_fetchpvn
gv_fetchpvn_flags
gv_fetchpvs
gv_fetchsv
gv_fetchsv_nomg
These all return the GV of type sv_type
whose name is given by the inputs, or NULL if no GV of that name and type could be found. See "Stashes and Globs" in perlguts.
The only differences are how the input name is specified, and if 'get' magic is normally used in getting that name.
Don't be fooled by the fact that only one form has flags
in its name. They all have a flags
parameter in fact, and all the flag bits have the same meanings for all
If any of the flags GV_ADD
, GV_ADDMG
, GV_ADDWARN
, GV_ADDMULTI
, or GV_NOINIT
is set, a GV is created if none already exists for the input name and type. However, GV_ADDMG
will only do the creation for magical GV's. For all of these flags except GV_NOINIT
, "gv_init_pvn"
is called after the addition. GV_ADDWARN
is used when the caller expects that adding won't be necessary because the symbol should already exist; but if not, add it anyway, with a warning that it was unexpectedly absent. The GV_ADDMULTI
flag means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
The flag GV_NOADD_NOINIT
causes "gv_init_pvn"
not be to called if the GV existed but isn't PVGV.
If the SVf_UTF8
bit is set, the name is treated as being encoded in UTF-8; otherwise the name won't be considered to be UTF-8 in the pv
-named forms, and the UTF-8ness of the underlying SVs will be used in the sv
forms.
If the flag GV_NOTQUAL
is set, the caller warrants that the input name is a plain symbol name, not qualified with a package, otherwise the name is checked for being a qualified one.
In gv_fetchpv
, nambeg
is a C string, NUL-terminated with no intermediate NULs.
In gv_fetchpvs
, name
is a literal C string, hence is enclosed in double quotes.
gv_fetchpvn
and gv_fetchpvn_flags
are identical. In these, <nambeg> is a Perl string whose byte length is given by full_len
, and may contain embedded NULs.
In gv_fetchsv
and gv_fetchsv_nomg
, the name is extracted from the PV of the input name
SV. The only difference between these two forms is that 'get' magic is normally done on name
in gv_fetchsv
, and always skipped with gv_fetchsv_nomg
. Including GV_NO_SVGMAGIC
in the flags
parameter to gv_fetchsv
makes it behave identically to gv_fetchsv_nomg
.
GV* gv_fetchpv (const char *nambeg, I32 flags, const svtype sv_type) GV * gv_fetchpvn (const char * nambeg, STRLEN full_len, I32 flags, const svtype sv_type) GV* gv_fetchpvn_flags(const char* name, STRLEN len, I32 flags, const svtype sv_type) GV * gv_fetchpvs ("name", I32 flags, const svtype sv_type) GV* gv_fetchsv (SV *name, I32 flags, const svtype sv_type) GV * gv_fetchsv_nomg (SV *name, I32 flags, const svtype sv_type)
gv_fullname3
gv_fullname4
gv_efullname3
gv_efullname4
Place the full package name of gv
into sv
. The gv_e*
forms return instead the effective package name (see "HvENAME").
If prefix
is non-NULL, it is considered to be a C language NUL-terminated string, and the stored name will be prefaced with it.
The other difference between the functions is that the *4
forms have an extra parameter, keepmain
. If true
an initial main::
in the name is kept; if false
it is stripped. With the *3
forms, it is always kept.
void gv_fullname3 (SV* sv, const GV* gv, const char* prefix) void gv_fullname4 (SV* sv, const GV* gv, const char* prefix, bool keepmain) void gv_efullname3(SV* sv, const GV* gv, const char* prefix) void gv_efullname4(SV* sv, const GV* gv, const char* prefix, bool keepmain)
gv_init
The old form of gv_init_pvn()
. It does not work with UTF-8 strings, as it has no flags parameter. If the multi
parameter is set, the GV_ADDMULTI
flag will be passed to gv_init_pvn()
.
void gv_init(GV* gv, HV* stash, const char* name, STRLEN len, int multi)
gv_init_pv
Same as gv_init_pvn()
, but takes a nul-terminated string for the name instead of separate char * and length parameters.
void gv_init_pv(GV* gv, HV* stash, const char* name, U32 flags)
gv_init_pvn
Converts a scalar into a typeglob. This is an incoercible typeglob; assigning a reference to it will assign to one of its slots, instead of overwriting it as happens with typeglobs created by SvSetSV
. Converting any scalar that is SvOK()
may produce unpredictable results and is reserved for perl's internal use.
gv
is the scalar to be converted.
stash
is the parent stash/package, if any.
name
and len
give the name. The name must be unqualified; that is, it must not include the package name. If gv
is a stash element, it is the caller's responsibility to ensure that the name passed to this function matches the name of the element. If it does not match, perl's internal bookkeeping will get out of sync.
flags
can be set to SVf_UTF8
if name
is a UTF-8 string, or the return value of SvUTF8(sv). It can also take the GV_ADDMULTI
flag, which means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
void gv_init_pvn(GV* gv, HV* stash, const char* name, STRLEN len, U32 flags)
gv_init_sv
Same as gv_init_pvn()
, but takes an SV * for the name instead of separate char * and length parameters. flags
is currently unused.
void gv_init_sv(GV* gv, HV* stash, SV* namesv, U32 flags)
gv_stashpv
Returns a pointer to the stash for a specified package. Uses strlen
to determine the length of name
, then calls gv_stashpvn()
.
HV* gv_stashpv(const char* name, I32 flags)
gv_stashpvn
Returns a pointer to the stash for a specified package. The namelen
parameter indicates the length of the name
, in bytes. flags
is passed to gv_fetchpvn_flags()
, so if set to GV_ADD
then the package will be created if it does not already exist. If the package does not exist and flags
is 0 (or any other setting that does not create packages) then NULL
is returned.
Flags may be one of:
GV_ADD Create and initialize the package if doesn't already exist GV_NOADD_NOINIT Don't create the package, GV_ADDMG GV_ADD iff the GV is magical GV_NOINIT GV_ADD, but don't initialize GV_NOEXPAND Don't expand SvOK() entries to PVGV SVf_UTF8 The name is in UTF-8
The most important of which are probably GV_ADD
and SVf_UTF8
.
Note, use of gv_stashsv
instead of gv_stashpvn
where possible is strongly recommended for performance reasons.
HV* gv_stashpvn(const char* name, U32 namelen, I32 flags)
gv_stashpvs
Like gv_stashpvn
, but takes a literal string instead of a string/length pair.
HV* gv_stashpvs("name", I32 create)
gv_stashsv
Returns a pointer to the stash for a specified package. See "gv_stashpvn"
.
Note this interface is strongly preferred over gv_stashpvn
for performance reasons.
HV* gv_stashsv(SV* sv, I32 flags)
GvSV
Return the SV from the GV.
Prior to Perl v5.9.3, this would add a scalar if none existed. Nowadays, use "GvSVn"
for that, or compile perl with
. See perl5100delta.-DPERL_CREATE_GVSV
SV* GvSV(GV* gv)
GvSVn
Like "GvSV"
, but creates an empty scalar if none already exists.
SV* GvSVn(GV* gv)
newGVgen
newGVgen_flags
Create a new, guaranteed to be unique, GV in the package given by the NUL-terminated C language string pack
, and return a pointer to it.
For newGVgen
or if flags
in newGVgen_flags
is 0, pack
is to be considered to be encoded in Latin-1. The only other legal flags
value is SVf_UTF8
, which indicates pack
is to be considered to be encoded in UTF-8.
GV* newGVgen (const char* pack) GV* newGVgen_flags(const char* pack, U32 flags)
PL_curstash
The stash for the package code will be compiled into.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
HV* PL_curstash
PL_defgv
The GV representing *_
. Useful for access to $_
.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
GV * PL_defgv
PL_defstash
Described in perlguts.
save_gp
Saves the current GP of gv on the save stack to be restored on scope exit.
If empty
is true, replace the GP with a new GP.
If empty
is false, mark gv
with GVf_INTRO
so the next reference assigned is localized, which is how
works. local *foo = $someref;
void save_gp(GV* gv, I32 empty)
setdefout
Sets PL_defoutgv
, the default file handle for output, to the passed in typeglob. As PL_defoutgv
"owns" a reference on its typeglob, the reference count of the passed in typeglob is increased by one, and the reference count of the typeglob that PL_defoutgv
points to is decreased by one.
void setdefout(GV* gv)
These functions provide convenient and thread-safe means of manipulating hook variables.
wrap_op_checker
Puts a C function into the chain of check functions for a specified op type. This is the preferred way to manipulate the "PL_check" array. opcode
specifies which type of op is to be affected. new_checker
is a pointer to the C function that is to be added to that opcode's check chain, and old_checker_p
points to the storage location where a pointer to the next function in the chain will be stored. The value of new_checker
is written into the "PL_check" array, while the value previously stored there is written to *old_checker_p
.
"PL_check" is global to an entire process, and a module wishing to hook op checking may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location *old_checker_p
must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also marked static
to give it internal linkage) will be implicitly initialised appropriately, if it does not have an explicit initialiser. This function will only actually modify the check chain if it finds *old_checker_p
to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing "PL_check".
When this function is called, the function referenced by new_checker
must be ready to be called, except for *old_checker_p
being unfilled. In a threading situation, new_checker
may be called immediately, even before this function has returned. *old_checker_p
will always be appropriately set before new_checker
is called. If new_checker
decides not to do anything special with an op that it is given (which is the usual case for most uses of op check hooking), it must chain the check function referenced by *old_checker_p
.
Taken all together, XS code to hook an op checker should typically look something like this:
static Perl_check_t nxck_frob; static OP *myck_frob(pTHX_ OP *op) { ... op = nxck_frob(aTHX_ op); ... return op; } BOOT: wrap_op_checker(OP_FROB, myck_frob, &nxck_frob);
If you want to influence compilation of calls to a specific subroutine, then use "cv_set_call_checker_flags" rather than hooking checking of all entersub
ops.
void wrap_op_checker(Optype opcode, Perl_check_t new_checker, Perl_check_t *old_checker_p)
A HV structure represents a Perl hash. It consists mainly of an array of pointers, each of which points to a linked list of HE structures. The array is indexed by the hash function of the key, so each linked list represents all the hash entries with the same hash value. Each HE contains a pointer to the actual value, plus a pointer to a HEK structure which holds the key and hash value.
get_hv
Returns the HV of the specified Perl hash. flags
are passed to gv_fetchpv
. If GV_ADD
is set and the Perl variable does not exist then it will be created. If flags
is zero and the variable does not exist then NULL
is returned.
NOTE: the perl_get_hv()
form is deprecated.
HV* get_hv(const char *name, I32 flags)
HE
Described in perlguts.
HEf_SVKEY
This flag, used in the length slot of hash entries and magic structures, specifies the structure contains an SV*
pointer where a char*
pointer is to be expected. (For information only--not to be used).
HeKEY
Returns the actual pointer stored in the key slot of the hash entry. The pointer may be either char*
or SV*
, depending on the value of HeKLEN()
. Can be assigned to. The HePV()
or HeSVKEY()
macros are usually preferable for finding the value of a key.
void* HeKEY(HE* he)
HeKLEN
If this is negative, and amounts to HEf_SVKEY
, it indicates the entry holds an SV*
key. Otherwise, holds the actual length of the key. Can be assigned to. The HePV()
macro is usually preferable for finding key lengths.
STRLEN HeKLEN(HE* he)
HePV
Returns the key slot of the hash entry as a char*
value, doing any necessary dereferencing of possibly SV*
keys. The length of the string is placed in len
(this is a macro, so do not use &len
). If you do not care about what the length of the key is, you may use the global variable PL_na
, though this is rather less efficient than using a local variable. Remember though, that hash keys in perl are free to contain embedded nulls, so using strlen()
or similar is not a good way to find the length of hash keys. This is very similar to the SvPV()
macro described elsewhere in this document. See also "HeUTF8"
.
If you are using HePV
to get values to pass to newSVpvn()
to create a new SV, you should consider using newSVhek(HeKEY_hek(he))
as it is more efficient.
char* HePV(HE* he, STRLEN len)
HeSVKEY
Returns the key as an SV*
, or NULL
if the hash entry does not contain an SV*
key.
SV* HeSVKEY(HE* he)
HeSVKEY_force
Returns the key as an SV*
. Will create and return a temporary mortal SV*
if the hash entry contains only a char*
key.
SV* HeSVKEY_force(HE* he)
HeSVKEY_set
Sets the key to a given SV*
, taking care to set the appropriate flags to indicate the presence of an SV*
key, and returns the same SV*
.
SV* HeSVKEY_set(HE* he, SV* sv)
HeUTF8
Returns whether the char *
value returned by HePV
is encoded in UTF-8, doing any necessary dereferencing of possibly SV*
keys. The value returned will be 0 or non-0, not necessarily 1 (or even a value with any low bits set), so do not blindly assign this to a bool
variable, as bool
may be a typedef for char
.
U32 HeUTF8(HE* he)
HeVAL
Returns the value slot (type SV*
) stored in the hash entry. Can be assigned to.
SV *foo= HeVAL(hv); HeVAL(hv)= sv;
SV* HeVAL(HE* he)
HV
Described in perlguts.
hv_assert
Check that a hash is in an internally consistent state.
NOTE: hv_assert
must be explicitly called as Perl_hv_assert
with an aTHX_
parameter.
void Perl_hv_assert(pTHX_ HV *hv)
hv_bucket_ratio
NOTE: hv_bucket_ratio
is experimental and may change or be removed without notice.
If the hash is tied dispatches through to the SCALAR tied method, otherwise if the hash contains no keys returns 0, otherwise returns a mortal sv containing a string specifying the number of used buckets, followed by a slash, followed by the number of available buckets.
This function is expensive, it must scan all of the buckets to determine which are used, and the count is NOT cached. In a large hash this could be a lot of buckets.
SV* hv_bucket_ratio(HV *hv)
hv_clear
Frees all the elements of a hash, leaving it empty. The XS equivalent of %hash = ()
. See also "hv_undef".
See "av_clear" for a note about the hash possibly being invalid on return.
void hv_clear(HV *hv)
hv_clear_placeholders
Clears any placeholders from a hash. If a restricted hash has any of its keys marked as readonly and the key is subsequently deleted, the key is not actually deleted but is marked by assigning it a value of &PL_sv_placeholder
. This tags it so it will be ignored by future operations such as iterating over the hash, but will still allow the hash to have a value reassigned to the key at some future point. This function clears any such placeholder keys from the hash. See Hash::Util::lock_keys()
for an example of its use.
void hv_clear_placeholders(HV *hv)
hv_copy_hints_hv
A specialised version of "newHVhv" for copying %^H
. ohv
must be a pointer to a hash (which may have %^H
magic, but should be generally non-magical), or NULL
(interpreted as an empty hash). The content of ohv
is copied to a new hash, which has the %^H
-specific magic added to it. A pointer to the new hash is returned.
HV * hv_copy_hints_hv(HV *const ohv)
hv_delete
Deletes a key/value pair in the hash. The value's SV is removed from the hash, made mortal, and returned to the caller. The absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode. The flags
value will normally be zero; if set to G_DISCARD
then NULL
will be returned. NULL
will also be returned if the key is not found.
SV* hv_delete(HV *hv, const char *key, I32 klen, I32 flags)
hv_delete_ent
Deletes a key/value pair in the hash. The value SV is removed from the hash, made mortal, and returned to the caller. The flags
value will normally be zero; if set to G_DISCARD
then NULL
will be returned. NULL
will also be returned if the key is not found. hash
can be a valid precomputed hash value, or 0 to ask for it to be computed.
SV* hv_delete_ent(HV *hv, SV *keysv, I32 flags, U32 hash)
HvENAME
Returns the effective name of a stash, or NULL if there is none. The effective name represents a location in the symbol table where this stash resides. It is updated automatically when packages are aliased or deleted. A stash that is no longer in the symbol table has no effective name. This name is preferable to HvNAME
for use in MRO linearisations and isa caches.
char* HvENAME(HV* stash)
HvENAMEUTF8
Returns true if the effective name is in UTF-8 encoding.
unsigned char HvENAMEUTF8(HV *stash)
hv_exists
Returns a boolean indicating whether the specified hash key exists. The absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode.
bool hv_exists(HV *hv, const char *key, I32 klen)
hv_exists_ent
Returns a boolean indicating whether the specified hash key exists. hash
can be a valid precomputed hash value, or 0 to ask for it to be computed.
bool hv_exists_ent(HV *hv, SV *keysv, U32 hash)
hv_fetch
Returns the SV which corresponds to the specified key in the hash. The absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode. If lval
is set then the fetch will be part of a store. This means that if there is no value in the hash associated with the given key, then one is created and a pointer to it is returned. The SV*
it points to can be assigned to. But always check that the return value is non-null before dereferencing it to an SV*
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
SV** hv_fetch(HV *hv, const char *key, I32 klen, I32 lval)
hv_fetchs
Like hv_fetch
, but takes a literal string instead of a string/length pair.
SV** hv_fetchs(HV* tb, "key", I32 lval)
hv_fetch_ent
Returns the hash entry which corresponds to the specified key in the hash. hash
must be a valid precomputed hash number for the given key
, or 0 if you want the function to compute it. IF lval
is set then the fetch will be part of a store. Make sure the return value is non-null before accessing it. The return value when hv
is a tied hash is a pointer to a static location, so be sure to make a copy of the structure if you need to store it somewhere.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
HE* hv_fetch_ent(HV *hv, SV *keysv, I32 lval, U32 hash)
HvFILL
Returns the number of hash buckets that happen to be in use.
As of perl 5.25 this function is used only for debugging purposes, and the number of used hash buckets is not in any way cached, thus this function can be costly to execute as it must iterate over all the buckets in the hash.
STRLEN HvFILL(HV *const hv)
hv_iterinit
Prepares a starting point to traverse a hash table. Returns the number of keys in the hash, including placeholders (i.e. the same as HvTOTALKEYS(hv)
). The return value is currently only meaningful for hashes without tie magic.
NOTE: Before version 5.004_65, hv_iterinit
used to return the number of hash buckets that happen to be in use. If you still need that esoteric value, you can get it through the macro HvFILL(hv)
.
I32 hv_iterinit(HV *hv)
hv_iterkey
Returns the key from the current position of the hash iterator. See "hv_iterinit"
.
char* hv_iterkey(HE* entry, I32* retlen)
hv_iterkeysv
Returns the key as an SV*
from the current position of the hash iterator. The return value will always be a mortal copy of the key. Also see "hv_iterinit"
.
SV* hv_iterkeysv(HE* entry)
hv_iternext
Returns entries from a hash iterator. See "hv_iterinit"
.
You may call hv_delete
or hv_delete_ent
on the hash entry that the iterator currently points to, without losing your place or invalidating your iterator. Note that in this case the current entry is deleted from the hash with your iterator holding the last reference to it. Your iterator is flagged to free the entry on the next call to hv_iternext
, so you must not discard your iterator immediately else the entry will leak - call hv_iternext
to trigger the resource deallocation.
HE* hv_iternext(HV *hv)
hv_iternextsv
Performs an hv_iternext
, hv_iterkey
, and hv_iterval
in one operation.
SV* hv_iternextsv(HV *hv, char **key, I32 *retlen)
hv_iternext_flags
NOTE: hv_iternext_flags
is experimental and may change or be removed without notice.
Returns entries from a hash iterator. See "hv_iterinit"
and "hv_iternext"
. The flags
value will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS
is set the placeholders keys (for restricted hashes) will be returned in addition to normal keys. By default placeholders are automatically skipped over. Currently a placeholder is implemented with a value that is &PL_sv_placeholder
. Note that the implementation of placeholders and restricted hashes may change, and the implementation currently is insufficiently abstracted for any change to be tidy.
HE* hv_iternext_flags(HV *hv, I32 flags)
hv_iterval
Returns the value from the current position of the hash iterator. See "hv_iterkey"
.
SV* hv_iterval(HV *hv, HE *entry)
hv_magic
Adds magic to a hash. See "sv_magic"
.
void hv_magic(HV *hv, GV *gv, int how)
HvNAME
Returns the package name of a stash, or NULL
if stash
isn't a stash. See "SvSTASH"
, "CvSTASH"
.
char* HvNAME(HV* stash)
HvNAMELEN
Returns the length of the stash's name.
Disfavored forms of HvNAME and HvNAMELEN; suppress mention of them
STRLEN HvNAMELEN(HV *stash)
hv_scalar
Evaluates the hash in scalar context and returns the result.
When the hash is tied dispatches through to the SCALAR method, otherwise returns a mortal SV containing the number of keys in the hash.
Note, prior to 5.25 this function returned what is now returned by the hv_bucket_ratio() function.
SV* hv_scalar(HV *hv)
hv_store
Stores an SV in a hash. The hash key is specified as key
and the absolute value of klen
is the length of the key. If klen
is negative the key is assumed to be in UTF-8-encoded Unicode. The hash
parameter is the precomputed hash value; if it is zero then Perl will compute it.
The return value will be NULL
if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise it can be dereferenced to get the original SV*
. Note that the caller is responsible for suitably incrementing the reference count of val
before the call, and decrementing it if the function returned NULL
. Effectively a successful hv_store
takes ownership of one reference to val
. This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash, hv_store
will own the only reference to the new SV, and your code doesn't need to do anything further to tidy up. hv_store
is not implemented as a call to hv_store_ent
, and does not create a temporary SV for the key, so if your key data is not already in SV form then use hv_store
in preference to hv_store_ent
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
SV** hv_store(HV *hv, const char *key, I32 klen, SV *val, U32 hash)
hv_stores
Like hv_store
, but takes a literal string instead of a string/length pair and omits the hash parameter.
SV** hv_stores(HV* tb, "key", SV* val)
hv_store_ent
Stores val
in a hash. The hash key is specified as key
. The hash
parameter is the precomputed hash value; if it is zero then Perl will compute it. The return value is the new hash entry so created. It will be NULL
if the operation failed or if the value did not need to be actually stored within the hash (as in the case of tied hashes). Otherwise the contents of the return value can be accessed using the He?
macros described here. Note that the caller is responsible for suitably incrementing the reference count of val
before the call, and decrementing it if the function returned NULL. Effectively a successful hv_store_ent
takes ownership of one reference to val
. This is usually what you want; a newly created SV has a reference count of one, so if all your code does is create SVs then store them in a hash, hv_store
will own the only reference to the new SV, and your code doesn't need to do anything further to tidy up. Note that hv_store_ent
only reads the key
; unlike val
it does not take ownership of it, so maintaining the correct reference count on key
is entirely the caller's responsibility. The reason it does not take ownership, is that key
is not used after this function returns, and so can be freed immediately. hv_store
is not implemented as a call to hv_store_ent
, and does not create a temporary SV for the key, so if your key data is not already in SV form then use hv_store
in preference to hv_store_ent
.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied hashes.
HE* hv_store_ent(HV *hv, SV *key, SV *val, U32 hash)
hv_undef
Undefines the hash. The XS equivalent of undef(%hash)
.
As well as freeing all the elements of the hash (like hv_clear()
), this also frees any auxiliary data and storage associated with the hash.
See "av_clear" for a note about the hash possibly being invalid on return.
void hv_undef(HV *hv)
newHVhv
The content of ohv
is copied to a new hash. A pointer to the new hash is returned.
HV* newHVhv(HV *hv)
Nullhv
DEPRECATED!
It is planned to remove Nullhv
from a future release of Perl. Do not use it for new code; remove it from existing code.
Null HV pointer.
(deprecated - use (HV *)NULL
instead)
PERL_HASH
Described in perlguts.
void PERL_HASH(U32 hash, char *key, STRLEN klen)
PL_modglobal
PL_modglobal
is a general purpose, interpreter global HV for use by extensions that need to keep information on a per-interpreter basis. In a pinch, it can also be used as a symbol table for extensions to share data among each other. It is a good idea to use keys prefixed by the package name of the extension that owns the data.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
HV* PL_modglobal
IoDIRP
Described in perlguts.
DIR * IoDIRP(IO *io)
IOf_FLUSH
Described in perlguts.
IoFLAGS
Described in perlguts.
U8 IoFLAGS(IO *io)
IOf_UNTAINT
Described in perlguts.
IoIFP
Described in perlguts.
PerlIO * IoIFP(IO *io)
IoOFP
Described in perlguts.
PerlIO * IoOFP(IO *io)
IoTYPE
Described in perlguts.
char IoTYPE(IO *io)
my_chsize
The C library chsize(3) if available, or a Perl implementation of it.
I32 my_chsize(int fd, Off_t length)
my_dirfd
The C library dirfd(3)
if available, or a Perl implementation of it, or die if not easily emulatable.
int my_dirfd(DIR* dir)
my_pclose
A wrapper for the C library pclose(3). Don't use the latter, as the Perl version knows things that interact with the rest of the perl interpreter.
I32 my_pclose(PerlIO* ptr)
my_popen
A wrapper for the C library popen(3). Don't use the latter, as the Perl version knows things that interact with the rest of the perl interpreter.
PerlIO* my_popen(const char* cmd, const char* mode)
PERL_FLUSHALL_FOR_CHILD
This defines a way to flush all output buffers. This may be a performance issue, so we allow people to disable it. Also, if we are using stdio, there are broken implementations of fflush(NULL) out there, Solaris being the most prominent.
void PERL_FLUSHALL_FOR_CHILD
PerlIO_apply_layers
PerlIO_binmode
PerlIO_canset_cnt
PerlIO_clearerr
PerlIO_close
PerlIO_debug
PerlIO_eof
PerlIO_error
PerlIO_exportFILE
PerlIO_fast_gets
PerlIO_fdopen
PerlIO_fileno
PerlIO_fill
PerlIO_findFILE
PerlIO_flush
PerlIO_get_base
PerlIO_get_bufsiz
PerlIO_getc
PerlIO_get_cnt
PerlIO_getpos
PerlIO_get_ptr
PerlIO_has_base
PerlIO_has_cntptr
PerlIO_importFILE
PerlIO_open
PerlIO_printf
PerlIO_putc
PerlIO_puts
PerlIO_read
PerlIO_releaseFILE
PerlIO_reopen
PerlIO_rewind
PerlIO_seek
PerlIO_set_cnt
PerlIO_setlinebuf
PerlIO_setpos
PerlIO_set_ptrcnt
PerlIO_stderr
PerlIO_stdin
PerlIO_stdout
PerlIO_stdoutf
PerlIO_tell
PerlIO_ungetc
PerlIO_unread
PerlIO_vprintf
PerlIO_write
Described in perlapio.
int PerlIO_apply_layers(PerlIO *f, const char *mode, const char *layers) int PerlIO_binmode (PerlIO *f, int ptype, int imode, const char *layers) int PerlIO_canset_cnt (PerlIO *f) void PerlIO_clearerr (PerlIO *f) int PerlIO_close (PerlIO *f) void PerlIO_debug (const char *fmt, ...) int PerlIO_eof (PerlIO *f) int PerlIO_error (PerlIO *f) FILE * PerlIO_exportFILE (PerlIO *f, const char *mode) int PerlIO_fast_gets (PerlIO *f) PerlIO * PerlIO_fdopen (int fd, const char *mode) int PerlIO_fileno (PerlIO *f) int PerlIO_fill (PerlIO *f) FILE * PerlIO_findFILE (PerlIO *f) int PerlIO_flush (PerlIO *f) STDCHAR * PerlIO_get_base (PerlIO *f) SSize_t PerlIO_get_bufsiz (PerlIO *f) int PerlIO_getc (PerlIO *d) SSize_t PerlIO_get_cnt (PerlIO *f) int PerlIO_getpos (PerlIO *f, SV *save) STDCHAR * PerlIO_get_ptr (PerlIO *f) int PerlIO_has_base (PerlIO *f) int PerlIO_has_cntptr (PerlIO *f) PerlIO * PerlIO_importFILE (FILE *stdio, const char *mode) PerlIO * PerlIO_open (const char *path, const char *mode) int PerlIO_printf (PerlIO *f, const char *fmt, ...) int PerlIO_putc (PerlIO *f, int ch) int PerlIO_puts (PerlIO *f, const char *string) SSize_t PerlIO_read (PerlIO *f, void *vbuf, Size_t count) void PerlIO_releaseFILE (PerlIO *f, FILE *stdio) PerlIO * PerlIO_reopen (const char *path, const char *mode, PerlIO *old) void PerlIO_rewind (PerlIO *f) int PerlIO_seek (PerlIO *f, Off_t offset, int whence) void PerlIO_set_cnt (PerlIO *f, SSize_t cnt) void PerlIO_setlinebuf (PerlIO *f) int PerlIO_setpos (PerlIO *f, SV *saved) void PerlIO_set_ptrcnt (PerlIO *f, STDCHAR *ptr, SSize_t cnt) PerlIO * PerlIO_stderr (PerlIO *f, const char *mode, const char *layers) PerlIO * PerlIO_stdin (PerlIO *f, const char *mode, const char *layers) PerlIO * PerlIO_stdout (PerlIO *f, const char *mode, const char *layers) int PerlIO_stdoutf (const char *fmt, ...) Off_t PerlIO_tell (PerlIO *f) int PerlIO_ungetc (PerlIO *f, int ch) SSize_t PerlIO_unread (PerlIO *f, const void *vbuf, Size_t count) int PerlIO_vprintf (PerlIO *f, const char *fmt, va_list args) SSize_t PerlIO_write (PerlIO *f, const void *vbuf, Size_t count)
PERLIO_FUNCS_DECL
Declare ftab
to be a PerlIO function table, that is, of type PerlIO_funcs
.
PERLIO_FUNCS_DECL(PerlIO * ftab)
PERLIO_F_APPEND
PERLIO_F_CANREAD
PERLIO_F_CANWRITE
PERLIO_F_CRLF
PERLIO_F_EOF
PERLIO_F_ERROR
PERLIO_F_FASTGETS
PERLIO_F_LINEBUF
PERLIO_F_OPEN
PERLIO_F_RDBUF
PERLIO_F_TEMP
PERLIO_F_TRUNCATE
PERLIO_F_UNBUF
PERLIO_F_UTF8
PERLIO_F_WRBUF
Described in perliol.
PERLIO_K_BUFFERED
PERLIO_K_CANCRLF
PERLIO_K_FASTGETS
PERLIO_K_MULTIARG
PERLIO_K_RAW
Described in perliol.
PERLIO_NOT_STDIO
Described in perlapio.
PL_maxsysfd
Described in perliol.
repeatcpy
Make count
copies of the len
bytes beginning at from
, placing them into memory beginning at to
, which must be big enough to accommodate them all.
void repeatcpy(char* to, const char* from, I32 len, IV count)
USE_STDIO
Described in perlapio.
CASTI32
This symbol is defined if the C compiler can cast negative or large floating point numbers to 32-bit ints.
HAS_INT64_T
This symbol will defined if the C compiler supports int64_t
. Usually the inttypes.h needs to be included, but sometimes sys/types.h is enough.
HAS_QUAD
This symbol, if defined, tells that there's a 64-bit integer type, Quad_t
, and its unsigned counterpart, Uquad_t
. QUADKIND
will be one of QUAD_IS_INT
, QUAD_IS_LONG
, QUAD_IS_LONG_LONG
, QUAD_IS_INT64_T
, or QUAD_IS___INT64
.
I8
I16
I32
I64
IV
Described in perlguts.
INT16_C
INT32_C
INT64_C
Returns a token the C compiler recognizes for the constant number
of the corresponding integer type on the machine.
If the machine does not have a 64-bit type, INT64_C
is undefined. Use "INTMAX_C"
to get the largest type available on the platform.
I16 INT16_C(number) I32 INT32_C(number) I64 INT64_C(number)
INTMAX_C
Returns a token the C compiler recognizes for the constant number
of the widest integer type on the machine. For example, if the machine has long long
s, INTMAX_C(-1)
would yield
-1LL
See also, for example, "INT32_C"
.
Use "IV" to declare variables of the maximum usable size on this platform.
INTMAX_C(number)
INTSIZE
This symbol contains the value of sizeof(int)
so that the C preprocessor can make decisions based on it.
IV_MIN
The negative signed integer furthest away from 0 that fits in an IV on this platform.
IV IV_MIN
LONGLONGSIZE
This symbol contains the size of a long long, so that the C preprocessor can make decisions based on it. It is only defined if the system supports long long.
LONGSIZE
This symbol contains the value of sizeof(long)
so that the C preprocessor can make decisions based on it.
PERL_INT_FAST8_T
PERL_INT_FAST16_T
PERL_UINT_FAST8_T
PERL_UINT_FAST16_T
These are equivalent to the correspondingly-named C99 typedefs on platforms that have those; they evaluate to int
and unsigned int
on platforms that don't, so that you can portably take advantage of this C99 feature.
PERL_INT_MAX
PERL_INT_MIN
PERL_LONG_MAX
PERL_LONG_MIN
PERL_SHORT_MAX
PERL_SHORT_MIN
PERL_UCHAR_MAX
PERL_UCHAR_MIN
PERL_UINT_MAX
PERL_UINT_MIN
PERL_ULONG_MAX
PERL_ULONG_MIN
PERL_USHORT_MAX
PERL_USHORT_MIN
PERL_QUAD_MAX
PERL_QUAD_MIN
PERL_UQUAD_MAX
PERL_UQUAD_MIN
These give the largest and smallest number representable in the current platform in variables of the corresponding types.
For signed types, the smallest representable number is the most negative number, the one furthest away from zero.
For C99 and later compilers, these correspond to things like INT_MAX
, which are available to the C code. But these constants, furnished by Perl, allow code compiled on earlier compilers to portably have access to the same constants.
SHORTSIZE
This symbol contains the value of sizeof(short)
so that the C preprocessor can make decisions based on it.
U8
U16
U32
U64
UV
Described in perlguts.
UINT16_C
UINT32_C
UINT64_C
Returns a token the C compiler recognizes for the constant number
of the corresponding unsigned integer type on the machine.
If the machine does not have a 64-bit type, UINT64_C
is undefined. Use "UINTMAX_C"
to get the largest type available on the platform.
U16 UINT16_C(number) U32 UINT32_C(number) U64 UINT64_C(number)
UINTMAX_C
Returns a token the C compiler recognizes for the constant number
of the widest unsigned integer type on the machine. For example, if the machine has long
s, UINTMAX_C(1)
would yield
1UL
See also, for example, "UINT32_C"
.
Use "UV" to declare variables of the maximum usable size on this platform.
UINTMAX_C(number)
These are used for formatting the corresponding type For example, instead of saying
Perl_newSVpvf(pTHX_ "Create an SV with a %d in it\n", iv);
use
Perl_newSVpvf(pTHX_ "Create an SV with a " IVdf " in it\n", iv);
This keeps you from having to know if, say an IV, needs to be printed as %d
, %ld
, or something else.
NVef
This symbol defines the format string used for printing a Perl NV using %e-ish floating point format.
NVff
This symbol defines the format string used for printing a Perl NV using %f-ish floating point format.
NVgf
This symbol defines the format string used for printing a Perl NV using %g-ish floating point format.
PERL_PRIeldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'e') for output.
PERL_PRIfldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'f') for output.
PERL_PRIgldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'g') for output.
PERL_SCNfldbl
This symbol, if defined, contains the string used by stdio to format long doubles (format 'f') for input.
SVf
Described in perlguts.
SVfARG
Described in perlguts.
SVfARG(SV *sv)
UTF8f
Described in perlguts.
UTF8fARG
Described in perlguts.
UTF8fARG(bool is_utf8, Size_t byte_len, char *str)
UVf
DEPRECATED!
It is planned to remove UVf
from a future release of Perl. Do not use it for new code; remove it from existing code.
Obsolete form of UVuf
, which you should convert to instead use
const char * UVf
UVof
This symbol defines the format string used for printing a Perl UV as an unsigned octal integer.
UVuf
This symbol defines the format string used for printing a Perl UV as an unsigned decimal integer.
This is the lower layer of the Perl parser, managing characters and tokens.
BHK
Described in perlguts.
lex_bufutf8
NOTE: lex_bufutf8
is experimental and may change or be removed without notice.
Indicates whether the octets in the lexer buffer ("PL_parser->linestr") should be interpreted as the UTF-8 encoding of Unicode characters. If not, they should be interpreted as Latin-1 characters. This is analogous to the SvUTF8
flag for scalars.
In UTF-8 mode, it is not guaranteed that the lexer buffer actually contains valid UTF-8. Lexing code must be robust in the face of invalid encoding.
The actual SvUTF8
flag of the "PL_parser->linestr" scalar is significant, but not the whole story regarding the input character encoding. Normally, when a file is being read, the scalar contains octets and its SvUTF8
flag is off, but the octets should be interpreted as UTF-8 if the use utf8
pragma is in effect. During a string eval, however, the scalar may have the SvUTF8
flag on, and in this case its octets should be interpreted as UTF-8 unless the use bytes
pragma is in effect. This logic may change in the future; use this function instead of implementing the logic yourself.
bool lex_bufutf8()
lex_discard_to
NOTE: lex_discard_to
is experimental and may change or be removed without notice.
Discards the first part of the "PL_parser->linestr" buffer, up to ptr
. The remaining content of the buffer will be moved, and all pointers into the buffer updated appropriately. ptr
must not be later in the buffer than the position of "PL_parser->bufptr": it is not permitted to discard text that has yet to be lexed.
Normally it is not necessarily to do this directly, because it suffices to use the implicit discarding behaviour of "lex_next_chunk" and things based on it. However, if a token stretches across multiple lines, and the lexing code has kept multiple lines of text in the buffer for that purpose, then after completion of the token it would be wise to explicitly discard the now-unneeded earlier lines, to avoid future multi-line tokens growing the buffer without bound.
void lex_discard_to(char* ptr)
lex_grow_linestr
NOTE: lex_grow_linestr
is experimental and may change or be removed without notice.
Reallocates the lexer buffer ("PL_parser->linestr") to accommodate at least len
octets (including terminating NUL
). Returns a pointer to the reallocated buffer. This is necessary before making any direct modification of the buffer that would increase its length. "lex_stuff_pvn" provides a more convenient way to insert text into the buffer.
Do not use SvGROW
or sv_grow
directly on PL_parser->linestr
; this function updates all of the lexer's variables that point directly into the buffer.
char* lex_grow_linestr(STRLEN len)
lex_next_chunk
NOTE: lex_next_chunk
is experimental and may change or be removed without notice.
Reads in the next chunk of text to be lexed, appending it to "PL_parser->linestr". This should be called when lexing code has looked to the end of the current chunk and wants to know more. It is usual, but not necessary, for lexing to have consumed the entirety of the current chunk at this time.
If "PL_parser->bufptr" is pointing to the very end of the current chunk (i.e., the current chunk has been entirely consumed), normally the current chunk will be discarded at the same time that the new chunk is read in. If flags
has the LEX_KEEP_PREVIOUS
bit set, the current chunk will not be discarded. If the current chunk has not been entirely consumed, then it will not be discarded regardless of the flag.
Returns true if some new text was added to the buffer, or false if the buffer has reached the end of the input text.
bool lex_next_chunk(U32 flags)
lex_peek_unichar
NOTE: lex_peek_unichar
is experimental and may change or be removed without notice.
Looks ahead one (Unicode) character in the text currently being lexed. Returns the codepoint (unsigned integer value) of the next character, or -1 if lexing has reached the end of the input text. To consume the peeked character, use "lex_read_unichar".
If the next character is in (or extends into) the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but if flags
has the LEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding error is encountered, an exception is generated.
I32 lex_peek_unichar(U32 flags)
lex_read_space
NOTE: lex_read_space
is experimental and may change or be removed without notice.
Reads optional spaces, in Perl style, in the text currently being lexed. The spaces may include ordinary whitespace characters and Perl-style comments. #line
directives are processed if encountered. "PL_parser->bufptr" is moved past the spaces, so that it points at a non-space character (or the end of the input text).
If spaces extend into the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but if flags
has the LEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
void lex_read_space(U32 flags)
lex_read_to
NOTE: lex_read_to
is experimental and may change or be removed without notice.
Consume text in the lexer buffer, from "PL_parser->bufptr" up to ptr
. This advances "PL_parser->bufptr" to match ptr
, performing the correct bookkeeping whenever a newline character is passed. This is the normal way to consume lexed text.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level functions "lex_peek_unichar" and "lex_read_unichar".
void lex_read_to(char* ptr)
lex_read_unichar
NOTE: lex_read_unichar
is experimental and may change or be removed without notice.
Reads the next (Unicode) character in the text currently being lexed. Returns the codepoint (unsigned integer value) of the character read, and moves "PL_parser->bufptr" past the character, or returns -1 if lexing has reached the end of the input text. To non-destructively examine the next character, use "lex_peek_unichar" instead.
If the next character is in (or extends into) the next chunk of input text, the next chunk will be read in. Normally the current chunk will be discarded at the same time, but if flags
has the LEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
If the input is being interpreted as UTF-8 and a UTF-8 encoding error is encountered, an exception is generated.
I32 lex_read_unichar(U32 flags)
lex_start
NOTE: lex_start
is experimental and may change or be removed without notice.
Creates and initialises a new lexer/parser state object, supplying a context in which to lex and parse from a new source of Perl code. A pointer to the new state object is placed in "PL_parser". An entry is made on the save stack so that upon unwinding, the new state object will be destroyed and the former value of "PL_parser" will be restored. Nothing else need be done to clean up the parsing context.
The code to be parsed comes from line
and rsfp
. line
, if non-null, provides a string (in SV form) containing code to be parsed. A copy of the string is made, so subsequent modification of line
does not affect parsing. rsfp
, if non-null, provides an input stream from which code will be read to be parsed. If both are non-null, the code in line
comes first and must consist of complete lines of input, and rsfp
supplies the remainder of the source.
The flags
parameter is reserved for future use. Currently it is only used by perl internally, so extensions should always pass zero.
void lex_start(SV* line, PerlIO *rsfp, U32 flags)
lex_stuff_pv
NOTE: lex_stuff_pv
is experimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by octets starting at pv
and continuing to the first nul. These octets are interpreted as either UTF-8 or Latin-1, according to whether the LEX_STUFF_UTF8
flag is set in flags
. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If it is not convenient to nul-terminate a string to be inserted, the "lex_stuff_pvn" function is more appropriate.
void lex_stuff_pv(const char* pv, U32 flags)
lex_stuff_pvn
NOTE: lex_stuff_pvn
is experimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by len
octets starting at pv
. These octets are interpreted as either UTF-8 or Latin-1, according to whether the LEX_STUFF_UTF8
flag is set in flags
. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string to be inserted is available as a Perl scalar, the "lex_stuff_sv" function is more convenient.
void lex_stuff_pvn(const char* pv, STRLEN len, U32 flags)
lex_stuff_pvs
NOTE: lex_stuff_pvs
is experimental and may change or be removed without notice.
Like "lex_stuff_pvn", but takes a literal string instead of a string/length pair.
void lex_stuff_pvs("pv", U32 flags)
lex_stuff_sv
NOTE: lex_stuff_sv
is experimental and may change or be removed without notice.
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing code that runs later will see the characters as if they had appeared in the input. It is not recommended to do this as part of normal parsing, and most uses of this facility run the risk of the inserted characters being interpreted in an unintended manner.
The string to be inserted is the string value of sv
. The characters are recoded for the lexer buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string to be inserted is not already a Perl scalar, the "lex_stuff_pvn" function avoids the need to construct a scalar.
void lex_stuff_sv(SV* sv, U32 flags)
lex_unstuff
NOTE: lex_unstuff
is experimental and may change or be removed without notice.
Discards text about to be lexed, from "PL_parser->bufptr" up to ptr
. Text following ptr
will be moved, and the buffer shortened. This hides the discarded text from any lexing code that runs later, as if the text had never appeared.
This is not the normal way to consume lexed text. For that, use "lex_read_to".
void lex_unstuff(char* ptr)
parse_arithexpr
NOTE: parse_arithexpr
is experimental and may change or be removed without notice.
Parse a Perl arithmetic expression. This may contain operators of precedence down to the bit shift operators. The expression must be followed (and thus terminated) either by a comparison or lower-precedence operator or by something that would normally terminate an expression such as semicolon. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP* parse_arithexpr(U32 flags)
parse_barestmt
NOTE: parse_barestmt
is experimental and may change or be removed without notice.
Parse a single unadorned Perl statement. This may be a normal imperative statement or a declaration that has compile-time effect. It does not include any label or other affixture. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement is null, for example if it was actually a subroutine definition (which has compile-time side effects). If not null, it will be ops directly implementing the statement, suitable to pass to "newSTATEOP". It will not normally include a nextstate
or equivalent op (except for those embedded in a scope contained entirely within the statement).
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP* parse_barestmt(U32 flags)
parse_block
NOTE: parse_block
is experimental and may change or be removed without notice.
Parse a single complete Perl code block. This consists of an opening brace, a sequence of statements, and a closing brace. The block constitutes a lexical scope, so my
variables and various compile-time effects can be contained within it. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the code block is returned. This is always a real op, never a null pointer. It will normally be a lineseq
list, including nextstate
or equivalent ops. No ops to construct any kind of runtime scope are included by virtue of it being a block.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP* parse_block(U32 flags)
parse_fullexpr
NOTE: parse_fullexpr
is experimental and may change or be removed without notice.
Parse a single complete Perl expression. This allows the full expression grammar, including the lowest-precedence operators such as or
. The expression must be followed (and thus terminated) by a token that an expression would normally be terminated by: end-of-file, closing bracketing punctuation, semicolon, or one of the keywords that signals a postfix expression-statement modifier. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP* parse_fullexpr(U32 flags)
parse_fullstmt
NOTE: parse_fullstmt
is experimental and may change or be removed without notice.
Parse a single complete Perl statement. This may be a normal imperative statement or a declaration that has compile-time effect, and may include optional labels. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement is null, for example if it was actually a subroutine definition (which has compile-time side effects). If not null, it will be the result of a "newSTATEOP" call, normally including a nextstate
or equivalent op.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP* parse_fullstmt(U32 flags)
parse_label
NOTE: parse_label
is experimental and may change or be removed without notice.
Parse a single label, possibly optional, of the type that may prefix a Perl statement. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed. If flags
has the PARSE_OPTIONAL
bit set, then the label is optional, otherwise it is mandatory.
The name of the label is returned in the form of a fresh scalar. If an optional label is absent, a null pointer is returned.
If an error occurs in parsing, which can only occur if the label is mandatory, a valid label is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred.
SV* parse_label(U32 flags)
parse_listexpr
NOTE: parse_listexpr
is experimental and may change or be removed without notice.
Parse a Perl list expression. This may contain operators of precedence down to the comma operator. The expression must be followed (and thus terminated) either by a low-precedence logic operator such as or
or by something that would normally terminate an expression such as semicolon. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP* parse_listexpr(U32 flags)
parse_stmtseq
NOTE: parse_stmtseq
is experimental and may change or be removed without notice.
Parse a sequence of zero or more Perl statements. These may be normal imperative statements, including optional labels, or declarations that have compile-time effect, or any mixture thereof. The statement sequence ends when a closing brace or end-of-file is encountered in a place where a new statement could have validly started. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the statements.
The op tree representing the statement sequence is returned. This may be a null pointer if the statements were all null, for example if there were no statements or if there were only subroutine definitions (which have compile-time side effects). If not null, it will be a lineseq
list, normally including nextstate
or equivalent ops.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
The flags
parameter is reserved for future use, and must always be zero.
OP* parse_stmtseq(U32 flags)
parse_subsignature
NOTE: parse_subsignature
is experimental and may change or be removed without notice.
Parse a subroutine signature declaration. This is the contents of the parentheses following a named or anonymous subroutine declaration when the signatures
feature is enabled. Note that this function neither expects nor consumes the opening and closing parentheses around the signature; it is the caller's job to handle these.
This function must only be called during parsing of a subroutine; after "start_subparse" has been called. It might allocate lexical variables on the pad for the current subroutine.
The op tree to unpack the arguments from the stack at runtime is returned. This op tree should appear at the beginning of the compiled function. The caller may wish to use "op_append_list" to build their function body after it, or splice it together with the body before calling "newATTRSUB".
The flags
parameter is reserved for future use, and must always be zero.
OP* parse_subsignature(U32 flags)
parse_termexpr
NOTE: parse_termexpr
is experimental and may change or be removed without notice.
Parse a Perl term expression. This may contain operators of precedence down to the assignment operators. The expression must be followed (and thus terminated) either by a comma or lower-precedence operator or by something that would normally terminate an expression such as semicolon. If flags
has the PARSE_OPTIONAL
bit set, then the expression is optional, otherwise it is mandatory. It is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed and the lexical context for the expression.
The op tree representing the expression is returned. If an optional expression is absent, a null pointer is returned, otherwise the pointer will be non-null.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. Some compilation errors, however, will throw an exception immediately.
OP* parse_termexpr(U32 flags)
PL_parser
Pointer to a structure encapsulating the state of the parsing operation currently in progress. The pointer can be locally changed to perform a nested parse without interfering with the state of an outer parse. Individual members of PL_parser
have their own documentation.
PL_parser->bufend
NOTE: PL_parser->bufend
is experimental and may change or be removed without notice.
Direct pointer to the end of the chunk of text currently being lexed, the end of the lexer buffer. This is equal to SvPVX(PL_parser->linestr) + SvCUR(PL_parser->linestr)
. A NUL
character (zero octet) is always located at the end of the buffer, and does not count as part of the buffer's contents.
PL_parser->bufptr
NOTE: PL_parser->bufptr
is experimental and may change or be removed without notice.
Points to the current position of lexing inside the lexer buffer. Characters around this point may be freely examined, within the range delimited by SvPVX("PL_parser->linestr")
and "PL_parser->bufend". The octets of the buffer may be intended to be interpreted as either UTF-8 or Latin-1, as indicated by "lex_bufutf8".
Lexing code (whether in the Perl core or not) moves this pointer past the characters that it consumes. It is also expected to perform some bookkeeping whenever a newline character is consumed. This movement can be more conveniently performed by the function "lex_read_to", which handles newlines appropriately.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level functions "lex_peek_unichar" and "lex_read_unichar".
PL_parser->linestart
NOTE: PL_parser->linestart
is experimental and may change or be removed without notice.
Points to the start of the current line inside the lexer buffer. This is useful for indicating at which column an error occurred, and not much else. This must be updated by any lexing code that consumes a newline; the function "lex_read_to" handles this detail.
PL_parser->linestr
NOTE: PL_parser->linestr
is experimental and may change or be removed without notice.
Buffer scalar containing the chunk currently under consideration of the text currently being lexed. This is always a plain string scalar (for which SvPOK
is true). It is not intended to be used as a scalar by normal scalar means; instead refer to the buffer directly by the pointer variables described below.
The lexer maintains various char*
pointers to things in the PL_parser->linestr
buffer. If PL_parser->linestr
is ever reallocated, all of these pointers must be updated. Don't attempt to do this manually, but rather use "lex_grow_linestr" if you need to reallocate the buffer.
The content of the text chunk in the buffer is commonly exactly one complete line of input, up to and including a newline terminator, but there are situations where it is otherwise. The octets of the buffer may be intended to be interpreted as either UTF-8 or Latin-1. The function "lex_bufutf8" tells you which. Do not use the SvUTF8
flag on this scalar, which may disagree with it.
For direct examination of the buffer, the variable "PL_parser->bufend" points to the end of the buffer. The current lexing position is pointed to by "PL_parser->bufptr". Direct use of these pointers is usually preferable to examination of the scalar through normal scalar means.
wrap_keyword_plugin
NOTE: wrap_keyword_plugin
is experimental and may change or be removed without notice.
Puts a C function into the chain of keyword plugins. This is the preferred way to manipulate the "PL_keyword_plugin" variable. new_plugin
is a pointer to the C function that is to be added to the keyword plugin chain, and old_plugin_p
points to the storage location where a pointer to the next function in the chain will be stored. The value of new_plugin
is written into the "PL_keyword_plugin" variable, while the value previously stored there is written to *old_plugin_p
.
"PL_keyword_plugin" is global to an entire process, and a module wishing to hook keyword parsing may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location *old_plugin_p
must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also marked static
to give it internal linkage) will be implicitly initialised appropriately, if it does not have an explicit initialiser. This function will only actually modify the plugin chain if it finds *old_plugin_p
to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing "PL_keyword_plugin".
When this function is called, the function referenced by new_plugin
must be ready to be called, except for *old_plugin_p
being unfilled. In a threading situation, new_plugin
may be called immediately, even before this function has returned. *old_plugin_p
will always be appropriately set before new_plugin
is called. If new_plugin
decides not to do anything special with the identifier that it is given (which is the usual case for most calls to a keyword plugin), it must chain the plugin function referenced by *old_plugin_p
.
Taken all together, XS code to install a keyword plugin should typically look something like this:
static Perl_keyword_plugin_t next_keyword_plugin; static OP *my_keyword_plugin(pTHX_ char *keyword_ptr, STRLEN keyword_len, OP **op_ptr) { if (memEQs(keyword_ptr, keyword_len, "my_new_keyword")) { ... } else { return next_keyword_plugin(aTHX_ keyword_ptr, keyword_len, op_ptr); } } BOOT: wrap_keyword_plugin(my_keyword_plugin, &next_keyword_plugin);
Direct access to "PL_keyword_plugin" should be avoided.
void wrap_keyword_plugin(Perl_keyword_plugin_t new_plugin, Perl_keyword_plugin_t *old_plugin_p)
DECLARATION_FOR_LC_NUMERIC_MANIPULATION
This macro should be used as a statement. It declares a private variable (whose name begins with an underscore) that is needed by the other macros in this section. Failing to include this correctly should lead to a syntax error. For compatibility with C89 C compilers it should be placed in a block before any executable statements.
void DECLARATION_FOR_LC_NUMERIC_MANIPULATION
foldEQ_locale
Returns true if the leading len
bytes of the strings s1
and s2
are the same case-insensitively in the current locale; false otherwise.
I32 foldEQ_locale(const char* a, const char* b, I32 len)
HAS_DUPLOCALE
This symbol, if defined, indicates that the duplocale
routine is available to duplicate a locale object.
HAS_FREELOCALE
This symbol, if defined, indicates that the freelocale
routine is available to deallocates the resources associated with a locale object.
HAS_LC_MONETARY_2008
This symbol, if defined, indicates that the localeconv routine is available and has the additional members added in POSIX
1003.1-2008.
HAS_LOCALECONV
This symbol, if defined, indicates that the localeconv
routine is available for numeric and monetary formatting conventions.
HAS_LOCALECONV_L
This symbol, if defined, indicates that the localeconv_l
routine is available to query certain information about a locale.
HAS_NEWLOCALE
This symbol, if defined, indicates that the newlocale
routine is available to return a new locale object or modify an existing locale object.
HAS_NL_LANGINFO
This symbol, if defined, indicates that the nl_langinfo
routine is available to return local data. You will also need langinfo.h and therefore I_LANGINFO
.
HAS_QUERYLOCALE
This symbol, if defined, indicates that the querylocale
routine is available to return the name of the locale for a category mask.
HAS_SETLOCALE
This symbol, if defined, indicates that the setlocale
routine is available to handle locale-specific ctype implementations.
HAS_SETLOCALE_R
This symbol, if defined, indicates that the setlocale_r
routine is available to setlocale re-entrantly.
HAS_THREAD_SAFE_NL_LANGINFO_L
This symbol, when defined, indicates presence of the nl_langinfo_l()
function, and that it is thread-safe.
HAS_USELOCALE
This symbol, if defined, indicates that the uselocale
routine is available to set the current locale for the calling thread.
I_LANGINFO
This symbol, if defined, indicates that langinfo.h exists and should be included.
#ifdef I_LANGINFO #include <langinfo.h> #endif
I_LOCALE
This symbol, if defined, indicates to the C program that it should include locale.h.
#ifdef I_LOCALE #include <locale.h> #endif
IN_LOCALE
Evaluates to TRUE if the plain locale pragma without a parameter (
) is in effect.use locale
bool IN_LOCALE
IN_LOCALE_COMPILETIME
Evaluates to TRUE if, when compiling a perl program (including an eval
) if the plain locale pragma without a parameter (
) is in effect.use locale
bool IN_LOCALE_COMPILETIME
IN_LOCALE_RUNTIME
Evaluates to TRUE if, when executing a perl program (including an eval
) if the plain locale pragma without a parameter (
) is in effect.use locale
bool IN_LOCALE_RUNTIME
I_XLOCALE
This symbol, if defined, indicates to the C program that the header xlocale.h is available. See also "NEED_XLOCALE_H"
#ifdef I_XLOCALE #include <xlocale.h> #endif
NEED_XLOCALE_H
This symbol, if defined, indicates that the C program should include xlocale.h to get newlocale()
and its friends.
Perl_langinfo
This is an (almost) drop-in replacement for the system nl_langinfo(3)
, taking the same item
parameter values, and returning the same information. But it is more thread-safe than regular nl_langinfo()
, and hides the quirks of Perl's locale handling from your code, and can be used on systems that lack a native nl_langinfo
.
Expanding on these:
const char *
, whereas plain nl_langinfo()
returns char *
, but you are (only by documentation) forbidden to write into the buffer. By declaring this const
, the compiler enforces this restriction, so if it is violated, you know at compilation time, rather than getting segfaults at runtime.RADIXCHAR
and THOUSEP
items, without you having to write extra code. The reason for the extra code would be because these are from the LC_NUMERIC
locale category, which is normally kept set by Perl so that the radix is a dot, and the separator is the empty string, no matter what the underlying locale is supposed to be, and so to get the expected results, you have to temporarily toggle into the underlying locale, and later toggle back. (You could use plain nl_langinfo
and "STORE_LC_NUMERIC_FORCE_TO_UNDERLYING"
for this but then you wouldn't get the other advantages of Perl_langinfo()
; not keeping LC_NUMERIC
in the C (or equivalent) locale would break a lot of CPAN, which is expecting the radix (decimal point) character to be a dot.)freelocale
, setlocale
, or other locale change. The returned buffer of this function is not changed until the next call to it, so the buffer is never in a trashed state.nl_langinfo
, such as Windows, hence makes your code more portable. Of the fifty-some possible items specified by the POSIX 2008 standard, http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html, only one is completely unimplemented, though on non-Windows platforms, another significant one is also not implemented). It uses various techniques to recover the other items, including calling localeconv(3)
, and strftime(3)
, both of which are specified in C89, so should be always be available. Later strftime()
versions have additional capabilities; ""
is returned for those not available on your system.
It is important to note that when called with an item that is recovered by using localeconv
, the buffer from any previous explicit call to localeconv
will be overwritten. This means you must save that buffer's contents if you need to access them after a call to this function. (But note that you might not want to be using localeconv()
directly anyway, because of issues like the ones listed in the second item of this list (above) for RADIXCHAR
and THOUSEP
. You can use the methods given in perlcall to call "localeconv" in POSIX and avoid all the issues, but then you have a hash to unpack).
The details for those items which may deviate from what this emulation returns and what a native nl_langinfo()
would return are specified in I18N::Langinfo.
When using Perl_langinfo
on systems that don't have a native nl_langinfo()
, you must
#include "perl_langinfo.h"
before the perl.h
#include
. You can replace your langinfo.h
#include
with this one. (Doing it this way keeps out the symbols that plain langinfo.h
would try to import into the namespace for code that doesn't need it.)
The original impetus for Perl_langinfo()
was so that code that needs to find out the current currency symbol, floating point radix character, or digit grouping separator can use, on all systems, the simpler and more thread-friendly nl_langinfo
API instead of localeconv(3)
which is a pain to make thread-friendly. For other fields returned by localeconv
, it is better to use the methods given in perlcall to call POSIX::localeconv()
, which is thread-friendly.
const char* Perl_langinfo(const nl_item item)
Perl_setlocale
This is an (almost) drop-in replacement for the system setlocale(3)
, taking the same parameters, and returning the same information, except that it returns the correct underlying LC_NUMERIC
locale. Regular setlocale
will instead return C
if the underlying locale has a non-dot decimal point character, or a non-empty thousands separator for displaying floating point numbers. This is because perl keeps that locale category such that it has a dot and empty separator, changing the locale briefly during the operations where the underlying one is required. Perl_setlocale
knows about this, and compensates; regular setlocale
doesn't.
Another reason it isn't completely a drop-in replacement is that it is declared to return
, whereas the system setlocale omits the const char *
const
(presumably because its API was specified long ago, and can't be updated; it is illegal to change the information setlocale
returns; doing so leads to segfaults.)
Finally, Perl_setlocale
works under all circumstances, whereas plain setlocale
can be completely ineffective on some platforms under some configurations.
Perl_setlocale
should not be used to change the locale except on systems where the predefined variable ${^SAFE_LOCALES}
is 1. On some such systems, the system setlocale()
is ineffective, returning the wrong information, and failing to actually change the locale. Perl_setlocale
, however works properly in all circumstances.
The return points to a per-thread static buffer, which is overwritten the next time Perl_setlocale
is called from the same thread.
const char* Perl_setlocale(const int category, const char* locale)
RESTORE_LC_NUMERIC
This is used in conjunction with one of the macros "STORE_LC_NUMERIC_SET_TO_NEEDED" and "STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" to properly restore the LC_NUMERIC
state.
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro and the two STORE
ones. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{ DECLARATION_FOR_LC_NUMERIC_MANIPULATION; ... RESTORE_LC_NUMERIC(); ... }
void RESTORE_LC_NUMERIC()
SETLOCALE_ACCEPTS_ANY_LOCALE_NAME
This symbol, if defined, indicates that the setlocale routine is available and it accepts any input locale name as valid.
STORE_LC_NUMERIC_FORCE_TO_UNDERLYING
This is used by XS code that is LC_NUMERIC
locale-aware to force the locale for category LC_NUMERIC
to be what perl thinks is the current underlying locale. (The perl interpreter could be wrong about what the underlying locale actually is if some C or XS code has called the C library function setlocale(3) behind its back; calling "sync_locale" before calling this macro will update perl's records.)
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{ DECLARATION_FOR_LC_NUMERIC_MANIPULATION; ... STORE_LC_NUMERIC_FORCE_TO_UNDERLYING(); ... RESTORE_LC_NUMERIC(); ... }
The private variable is used to save the current locale state, so that the requisite matching call to "RESTORE_LC_NUMERIC" can restore it.
On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called.
void STORE_LC_NUMERIC_FORCE_TO_UNDERLYING()
STORE_LC_NUMERIC_SET_TO_NEEDED
This is used to help wrap XS or C code that is LC_NUMERIC
locale-aware. This locale category is generally kept set to a locale where the decimal radix character is a dot, and the separator between groups of digits is empty. This is because most XS code that reads floating point numbers is expecting them to have this syntax.
This macro makes sure the current LC_NUMERIC
state is set properly, to be aware of locale if the call to the XS or C code from the Perl program is from within the scope of a
; or to ignore locale if the call is instead from outside such scope.use locale
This macro is the start of wrapping the C or XS code; the wrap ending is done by calling the "RESTORE_LC_NUMERIC" macro after the operation. Otherwise the state can be changed that will adversely affect other XS code.
A call to "DECLARATION_FOR_LC_NUMERIC_MANIPULATION" must have been made to declare at compile time a private variable used by this macro. This macro should be called as a single statement, not an expression, but with an empty argument list, like this:
{ DECLARATION_FOR_LC_NUMERIC_MANIPULATION; ... STORE_LC_NUMERIC_SET_TO_NEEDED(); ... RESTORE_LC_NUMERIC(); ... }
On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called; see "WITH_LC_NUMERIC_SET_TO_NEEDED" for a more contained way to ensure that.
void STORE_LC_NUMERIC_SET_TO_NEEDED()
STORE_LC_NUMERIC_SET_TO_NEEDED_IN
Same as "STORE_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided as the precalculated value of IN_LC(LC_NUMERIC)
. It is the caller's responsibility to ensure that the status of PL_compiling
and PL_hints
cannot have changed since the precalculation.
void STORE_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric)
switch_to_global_locale
On systems without locale support, or on typical single-threaded builds, or on platforms that do not support per-thread locale operations, this function does nothing. On such systems that do have locale support, only a locale global to the whole program is available.
On multi-threaded builds on systems that do have per-thread locale operations, this function converts the thread it is running in to use the global locale. This is for code that has not yet or cannot be updated to handle multi-threaded locale operation. As long as only a single thread is so-converted, everything works fine, as all the other threads continue to ignore the global one, so only this thread looks at it.
However, on Windows systems this isn't quite true prior to Visual Studio 15, at which point Microsoft fixed a bug. A race can occur if you use the following operations on earlier Windows platforms:
CRNCYSTR
and THOUSEP
CRNCYSTR
and THOUSEP
The first item is not fixable (except by upgrading to a later Visual Studio release), but it would be possible to work around the latter two items by using the Windows API functions GetNumberFormat
and GetCurrencyFormat
; patches welcome.
Without this function call, threads that use the setlocale(3)
system function will not work properly, as all the locale-sensitive functions will look at the per-thread locale, and setlocale
will have no effect on this thread.
Perl code should convert to either call Perl_setlocale
(which is a drop-in for the system setlocale
) or use the methods given in perlcall to call POSIX::setlocale
. Either one will transparently properly handle all cases of single- vs multi-thread, POSIX 2008-supported or not.
Non-Perl libraries, such as gtk
, that call the system setlocale
can continue to work if this function is called before transferring control to the library.
Upon return from the code that needs to use the global locale, sync_locale()
should be called to restore the safe multi-thread operation.
void switch_to_global_locale()
sync_locale
Perl_setlocale
can be used at any time to query or change the locale (though changing the locale is antisocial and dangerous on multi-threaded systems that don't have multi-thread safe locale operations. (See "Multi-threaded operation" in perllocale). Using the system setlocale(3)
should be avoided. Nevertheless, certain non-Perl libraries called from XS, such as Gtk
do so, and this can't be changed. When the locale is changed by XS code that didn't use Perl_setlocale
, Perl needs to be told that the locale has changed. Use this function to do so, before returning to Perl.
The return value is a boolean: TRUE if the global locale at the time of call was in effect; and FALSE if a per-thread locale was in effect. This can be used by the caller that needs to restore things as-they-were to decide whether or not to call Perl_switch_to_global_locale
.
bool sync_locale()
WITH_LC_NUMERIC_SET_TO_NEEDED
This macro invokes the supplied statement or block within the context of a "STORE_LC_NUMERIC_SET_TO_NEEDED" .. "RESTORE_LC_NUMERIC" pair if required, so eg:
WITH_LC_NUMERIC_SET_TO_NEEDED( SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis) );
is equivalent to:
{ #ifdef USE_LOCALE_NUMERIC DECLARATION_FOR_LC_NUMERIC_MANIPULATION; STORE_LC_NUMERIC_SET_TO_NEEDED(); #endif SNPRINTF_G(fv, ebuf, sizeof(ebuf), precis); #ifdef USE_LOCALE_NUMERIC RESTORE_LC_NUMERIC(); #endif }
void WITH_LC_NUMERIC_SET_TO_NEEDED(block)
WITH_LC_NUMERIC_SET_TO_NEEDED_IN
Same as "WITH_LC_NUMERIC_SET_TO_NEEDED" with in_lc_numeric provided as the precalculated value of IN_LC(LC_NUMERIC)
. It is the caller's responsibility to ensure that the status of PL_compiling
and PL_hints
cannot have changed since the precalculation.
void WITH_LC_NUMERIC_SET_TO_NEEDED_IN(bool in_lc_numeric, block)
"Magic" is special data attached to SV structures in order to give them "magical" properties. When any Perl code tries to read from, or assign to, an SV marked as magical, it calls the 'get' or 'set' function associated with that SV's magic. A get is called prior to reading an SV, in order to give it a chance to update its internal value (get on $. writes the line number of the last read filehandle into the SV's IV slot), while set is called after an SV has been written to, in order to allow it to make use of its changed value (set on $/ copies the SV's new value to the PL_rs global variable).
Magic is implemented as a linked list of MAGIC structures attached to the SV. Each MAGIC struct holds the type of the magic, a pointer to an array of functions that implement the get(), set(), length() etc functions, plus space for some flags and pointers. For example, a tied variable has a MAGIC structure that contains a pointer to the object associated with the tie.
mg_clear
Clear something magical that the SV represents. See "sv_magic"
.
int mg_clear(SV* sv)
mg_copy
Copies the magic from one SV to another. See "sv_magic"
.
int mg_copy(SV *sv, SV *nsv, const char *key, I32 klen)
MGf_COPY
MGf_DUP
MGf_LOCAL
Described in perlguts.
mg_find
Finds the magic pointer for type
matching the SV. See "sv_magic"
.
MAGIC* mg_find(const SV* sv, int type)
mg_findext
Finds the magic pointer of type
with the given vtbl
for the SV
. See "sv_magicext"
.
MAGIC* mg_findext(const SV* sv, int type, const MGVTBL *vtbl)
mg_free
Free any magic storage used by the SV. See "sv_magic"
.
int mg_free(SV* sv)
mg_freeext
Remove any magic of type how
using virtual table vtbl
from the SV sv
. See "sv_magic".
mg_freeext(sv, how, NULL)
is equivalent to mg_free_type(sv, how)
.
void mg_freeext(SV* sv, int how, const MGVTBL *vtbl)
mg_free_type
Remove any magic of type how
from the SV sv
. See "sv_magic".
void mg_free_type(SV* sv, int how)
mg_get
Do magic before a value is retrieved from the SV. The type of SV must be >= SVt_PVMG
. See "sv_magic"
.
int mg_get(SV* sv)
mg_length
DEPRECATED!
It is planned to remove mg_length
from a future release of Perl. Do not use it for new code; remove it from existing code.
Reports on the SV's length in bytes, calling length magic if available, but does not set the UTF8 flag on sv
. It will fall back to 'get' magic if there is no 'length' magic, but with no indication as to whether it called 'get' magic. It assumes sv
is a PVMG
or higher. Use sv_len()
instead.
U32 mg_length(SV* sv)
mg_magical
Turns on the magical status of an SV. See "sv_magic"
.
void mg_magical(SV* sv)
mg_set
Do magic after a value is assigned to the SV. See "sv_magic"
.
int mg_set(SV* sv)
MGVTBL
Described in perlguts.
perl_clone
Create and return a new interpreter by cloning the current one.
perl_clone
takes these flags as parameters:
CLONEf_COPY_STACKS
- is used to, well, copy the stacks also, without it we only clone the data and zero the stacks, with it we copy the stacks and the new perl interpreter is ready to run at the exact same point as the previous one. The pseudo-fork code uses COPY_STACKS
while the threads->create doesn't.
CLONEf_KEEP_PTR_TABLE
- perl_clone
keeps a ptr_table with the pointer of the old variable as a key and the new variable as a value, this allows it to check if something has been cloned and not clone it again, but rather just use the value and increase the refcount. If KEEP_PTR_TABLE
is not set then perl_clone
will kill the ptr_table using the function
. A reason to keep it around is if you want to dup some of your own variables which are outside the graph that perl scans.ptr_table_free(PL_ptr_table); PL_ptr_table = NULL;
CLONEf_CLONE_HOST
- This is a win32 thing, it is ignored on unix, it tells perl's win32host code (which is c++) to clone itself, this is needed on win32 if you want to run two threads at the same time, if you just want to do some stuff in a separate perl interpreter and then throw it away and return to the original one, you don't need to do anything.
PerlInterpreter* perl_clone(PerlInterpreter *proto_perl, UV flags)
PERL_MAGIC_arylen
PERL_MAGIC_arylen_p
PERL_MAGIC_backref
PERL_MAGIC_bm
PERL_MAGIC_checkcall
PERL_MAGIC_collxfrm
PERL_MAGIC_dbfile
PERL_MAGIC_dbline
PERL_MAGIC_debugvar
PERL_MAGIC_defelem
PERL_MAGIC_env
PERL_MAGIC_envelem
PERL_MAGIC_ext
PERL_MAGIC_fm
PERL_MAGIC_hints
PERL_MAGIC_hintselem
PERL_MAGIC_isa
PERL_MAGIC_isaelem
PERL_MAGIC_lvref
PERL_MAGIC_nkeys
PERL_MAGIC_nonelem
PERL_MAGIC_overload_table
PERL_MAGIC_pos
PERL_MAGIC_qr
PERL_MAGIC_regdata
PERL_MAGIC_regdatum
PERL_MAGIC_regex_global
PERL_MAGIC_rhash
PERL_MAGIC_shared
PERL_MAGIC_shared_scalar
PERL_MAGIC_sig
PERL_MAGIC_sigelem
PERL_MAGIC_substr
PERL_MAGIC_sv
PERL_MAGIC_symtab
PERL_MAGIC_taint
PERL_MAGIC_tied
PERL_MAGIC_tiedelem
PERL_MAGIC_tiedscalar
PERL_MAGIC_utf8
PERL_MAGIC_uvar
PERL_MAGIC_uvar_elem
PERL_MAGIC_vec
PERL_MAGIC_vstring
Described in perlguts.
ptr_table_fetch
Look for sv
in the pointer-mapping table tbl
, returning its value, or NULL if not found.
void* ptr_table_fetch(PTR_TBL_t *const tbl, const void *const sv)
ptr_table_split
Double the hash bucket size of an existing ptr table
void ptr_table_split(PTR_TBL_t *const tbl)
ptr_table_store
Add a new entry to a pointer-mapping table tbl
. In hash terms, oldsv
is the key; Cnewsv> is the value.
The names "old" and "new" are specific to the core's typical use of ptr_tables in thread cloning.
void ptr_table_store(PTR_TBL_t *const tbl, const void *const oldsv, void *const newsv)
SvTIED_obj
Described in perlinterp.
SvTIED_obj(SV *sv, MAGIC *mg)
dump_mstats
When enabled by compiling with -DDEBUGGING_MSTATS
, print out statistics about malloc as two lines of numbers, one showing the length of the free list for each size category, the second showing the number of mallocs - frees
for each size category.
s
, if not NULL, is used as a phrase to include in the output, such as "after compilation"
.
void dump_mstats(const char* s)
HAS_MALLOC_GOOD_SIZE
This symbol, if defined, indicates that the malloc_good_size
routine is available for use.
HAS_MALLOC_SIZE
This symbol, if defined, indicates that the malloc_size
routine is available for use.
I_MALLOCMALLOC
This symbol, if defined, indicates to the C program that it should include malloc/malloc.h.
#ifdef I_MALLOCMALLOC #include <mallocmalloc.h> #endif
Newx
safemalloc
The XSUB-writer's interface to the C malloc
function.
Memory obtained by this should ONLY be freed with "Safefree".
In 5.9.3, Newx() and friends replace the older New() API, and drops the first parameter, x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG (see "PERL_MEM_LOG" in perlhacktips). The older API is still there for use in XS modules supporting older perls.
void Newx (void* ptr, int nitems, type) void* safemalloc(size_t size)
Newxc
The XSUB-writer's interface to the C malloc
function, with cast. See also "Newx"
.
Memory obtained by this should ONLY be freed with "Safefree".
void Newxc(void* ptr, int nitems, type, cast)
Newxz
safecalloc
The XSUB-writer's interface to the C malloc
function. The allocated memory is zeroed with memzero
. See also "Newx"
.
Memory obtained by this should ONLY be freed with "Safefree".
void Newxz (void* ptr, int nitems, type) void* safecalloc(size_t nitems, size_t item_size)
Renew
saferealloc
The XSUB-writer's interface to the C realloc
function.
Memory obtained by this should ONLY be freed with "Safefree".
void Renew (void* ptr, int nitems, type) void* saferealloc(void *ptr, size_t size)
Renewc
The XSUB-writer's interface to the C realloc
function, with cast.
Memory obtained by this should ONLY be freed with "Safefree".
void Renewc(void* ptr, int nitems, type, cast)
Safefree
The XSUB-writer's interface to the C free
function.
This should ONLY be used on memory obtained using "Newx" and friends.
void Safefree(void* ptr)
These functions are related to the method resolution order of perl classes Also see perlmroapi.
HvMROMETA
Described in perlmroapi.
struct mro_meta * HvMROMETA(HV *hv)
mro_get_from_name
Returns the previously registered mro with the given name
, or NULL if not registered. See "mro_register
".
NOTE: mro_get_from_name
must be explicitly called as Perl_mro_get_from_name
with an aTHX_
parameter.
const struct mro_alg * Perl_mro_get_from_name(pTHX_ SV *name)
mro_get_linear_isa
Returns the mro linearisation for the given stash. By default, this will be whatever mro_get_linear_isa_dfs
returns unless some other MRO is in effect for the stash. The return value is a read-only AV*.
You are responsible for SvREFCNT_inc()
on the return value if you plan to store it anywhere semi-permanently (otherwise it might be deleted out from under you the next time the cache is invalidated).
AV* mro_get_linear_isa(HV* stash)
MRO_GET_PRIVATE_DATA
Described in perlmroapi.
SV* MRO_GET_PRIVATE_DATA(struct mro_meta *const smeta, const struct mro_alg *const which)
mro_method_changed_in
Invalidates method caching on any child classes of the given stash, so that they might notice the changes in this one.
Ideally, all instances of PL_sub_generation++
in perl source outside of mro.c should be replaced by calls to this.
Perl automatically handles most of the common ways a method might be redefined. However, there are a few ways you could change a method in a stash without the cache code noticing, in which case you need to call this method afterwards:
1) Directly manipulating the stash HV entries from XS code.
2) Assigning a reference to a readonly scalar constant into a stash entry in order to create a constant subroutine (like constant.pm does).
This same method is available from pure perl via, mro::method_changed_in(classname)
.
void mro_method_changed_in(HV* stash)
mro_register
Registers a custom mro plugin. See perlmroapi for details on this and other mro functions.
NOTE: mro_register
must be explicitly called as Perl_mro_register
with an aTHX_
parameter.
void Perl_mro_register(pTHX_ const struct mro_alg *mro)
mro_set_mro
Set meta
to the value contained in the registered mro plugin whose name is name
.
Croaks if name
hasn't been registered
NOTE: mro_set_mro
must be explicitly called as Perl_mro_set_mro
with an aTHX_
parameter.
void Perl_mro_set_mro(pTHX_ struct mro_meta *const meta, SV *const name)
mro_set_private_data
Described in perlmroapi.
NOTE: mro_set_private_data
must be explicitly called as Perl_mro_set_private_data
with an aTHX_
parameter.
SV* Perl_mro_set_private_data(pTHX_ struct mro_meta *const smeta, const struct mro_alg *const which, SV *const data)
dMULTICALL
Declare local variables for a multicall. See "LIGHTWEIGHT CALLBACKS" in perlcall.
dMULTICALL;
MULTICALL
Make a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
MULTICALL;
POP_MULTICALL
Closing bracket for a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
POP_MULTICALL;
PUSH_MULTICALL
Opening bracket for a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
PUSH_MULTICALL(CV* the_cv);
Atol
DEPRECATED!
It is planned to remove Atol
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlhacktips.
Atol(const char * nptr)
Atoul
DEPRECATED!
It is planned to remove Atoul
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlhacktips.
Atoul(const char * nptr)
Drand01
This macro is to be used to generate uniformly distributed random numbers over the range [0., 1.[. You may have to supply an 'extern double drand48()
;' in your program since SunOS 4.1.3 doesn't provide you with anything relevant in its headers. See "HAS_DRAND48_PROTO"
.
double Drand01()
Gconvert
This preprocessor macro is defined to convert a floating point number to a string without a trailing decimal point. This emulates the behavior of sprintf("%g")
, but is sometimes much more efficient. If gconvert()
is not available, but gcvt()
drops the trailing decimal point, then gcvt()
is used. If all else fails, a macro using sprintf("%g")
is used. Arguments for the Gconvert macro are: value, number of digits, whether trailing zeros should be retained, and the output buffer. The usual values are:
d_Gconvert='gconvert((x),(n),(t),(b))' d_Gconvert='gcvt((x),(n),(b))' d_Gconvert='sprintf((b),"%.*g",(n),(x))'
The last two assume trailing zeros should not be kept.
char * Gconvert(double x, Size_t n, bool t, char * b)
grok_atoUV
parse a string, looking for a decimal unsigned integer.
On entry, pv
points to the beginning of the string; valptr
points to a UV that will receive the converted value, if found; endptr
is either NULL or points to a variable that points to one byte beyond the point in pv
that this routine should examine. If endptr
is NULL, pv
is assumed to be NUL-terminated.
Returns FALSE if pv
doesn't represent a valid unsigned integer value (with no leading zeros). Otherwise it returns TRUE, and sets *valptr
to that value.
If you constrain the portion of pv
that is looked at by this function (by passing a non-NULL endptr
), and if the intial bytes of that portion form a valid value, it will return TRUE, setting *endptr
to the byte following the final digit of the value. But if there is no constraint at what's looked at, all of pv
must be valid in order for TRUE to be returned. *endptr
is unchanged from its value on input if FALSE is returned;
The only characters this accepts are the decimal digits '0'..'9'.
As opposed to atoi(3) or strtol(3), grok_atoUV
does NOT allow optional leading whitespace, nor negative inputs. If such features are required, the calling code needs to explicitly implement those.
Note that this function returns FALSE for inputs that would overflow a UV, or have leading zeros. Thus a single 0
is accepted, but not 00
nor 01
, 002
, etc.
Background: atoi
has severe problems with illegal inputs, it cannot be used for incremental parsing, and therefore should be avoided atoi
and strtol
are also affected by locale settings, which can also be seen as a bug (global state controlled by user environment).
bool grok_atoUV(const char* pv, UV* valptr, const char** endptr)
grok_bin
converts a string representing a binary number to numeric form.
On entry start
and *len_p
give the string to scan, *flags
gives conversion flags, and result
should be NULL
or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. Unless PERL_SCAN_SILENT_ILLDIGIT
is set in *flags
, encountering an invalid character (except NUL) will also trigger a warning. On return *len_p
is set to the length of the scanned string, and *flags
gives output flags.
If the value is <= UV_MAX
it is returned as a UV, the output flags are clear, and nothing is written to *result
. If the value is > UV_MAX
, grok_bin
returns UV_MAX
, sets PERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes an approximation of the correct value into *result
(which is an NV; or the approximation is discarded if result
is NULL).
The binary number may optionally be prefixed with "0b"
or "b"
unless PERL_SCAN_DISALLOW_PREFIX
is set in *flags
on entry.
If PERL_SCAN_ALLOW_UNDERSCORES
is set in *flags
then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
UV grok_bin(const char* start, STRLEN* len_p, I32* flags, NV *result)
grok_hex
converts a string representing a hex number to numeric form.
On entry start
and *len_p
give the string to scan, *flags
gives conversion flags, and result
should be NULL
or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. Unless PERL_SCAN_SILENT_ILLDIGIT
is set in *flags
, encountering an invalid character (except NUL) will also trigger a warning. On return *len_p
is set to the length of the scanned string, and *flags
gives output flags.
If the value is <= UV_MAX
it is returned as a UV, the output flags are clear, and nothing is written to *result
. If the value is > UV_MAX
, grok_hex
returns UV_MAX
, sets PERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes an approximation of the correct value into *result
(which is an NV; or the approximation is discarded if result
is NULL).
The hex number may optionally be prefixed with "0x"
or "x"
unless PERL_SCAN_DISALLOW_PREFIX
is set in *flags
on entry.
If PERL_SCAN_ALLOW_UNDERSCORES
is set in *flags
then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
UV grok_hex(const char* start, STRLEN* len_p, I32* flags, NV *result)
grok_infnan
Helper for grok_number()
, accepts various ways of spelling "infinity" or "not a number", and returns one of the following flag combinations:
IS_NUMBER_INFINITY IS_NUMBER_NAN IS_NUMBER_INFINITY | IS_NUMBER_NEG IS_NUMBER_NAN | IS_NUMBER_NEG 0
possibly |-ed with IS_NUMBER_TRAILING
.
If an infinity or a not-a-number is recognized, *sp
will point to one byte past the end of the recognized string. If the recognition fails, zero is returned, and *sp
will not move.
int grok_infnan(const char** sp, const char *send)
grok_number
Identical to grok_number_flags()
with flags
set to zero.
int grok_number(const char *pv, STRLEN len, UV *valuep)
grok_number_flags
Recognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise it is a bit-ORed combination of IS_NUMBER_IN_UV
, IS_NUMBER_GREATER_THAN_UV_MAX
, IS_NUMBER_NOT_INT
, IS_NUMBER_NEG
, IS_NUMBER_INFINITY
, IS_NUMBER_NAN
(defined in perl.h).
If the value of the number can fit in a UV, it is returned in *valuep
. IS_NUMBER_IN_UV
will be set to indicate that *valuep
is valid, IS_NUMBER_IN_UV
will never be set unless *valuep
is valid, but *valuep
may have been assigned to during processing even though IS_NUMBER_IN_UV
is not set on return. If valuep
is NULL
, IS_NUMBER_IN_UV
will be set for the same cases as when valuep
is non-NULL
, but no actual assignment (or SEGV) will occur.
IS_NUMBER_NOT_INT
will be set with IS_NUMBER_IN_UV
if trailing decimals were seen (in which case *valuep
gives the true value truncated to an integer), and IS_NUMBER_NEG
if the number is negative (in which case *valuep
holds the absolute value). IS_NUMBER_IN_UV
is not set if e
notation was used or the number is larger than a UV.
flags
allows only PERL_SCAN_TRAILING
, which allows for trailing non-numeric text on an otherwise successful grok, setting IS_NUMBER_TRAILING
on the result.
int grok_number_flags(const char *pv, STRLEN len, UV *valuep, U32 flags)
GROK_NUMERIC_RADIX
A synonym for "grok_numeric_radix"
bool GROK_NUMERIC_RADIX(NN const char **sp, NN const char *send)
grok_numeric_radix
Scan and skip for a numeric decimal separator (radix).
bool grok_numeric_radix(const char **sp, const char *send)
grok_oct
converts a string representing an octal number to numeric form.
On entry start
and *len_p
give the string to scan, *flags
gives conversion flags, and result
should be NULL
or a pointer to an NV. The scan stops at the end of the string, or at just before the first invalid character. Unless PERL_SCAN_SILENT_ILLDIGIT
is set in *flags
, encountering an invalid character (except NUL) will also trigger a warning. On return *len_p
is set to the length of the scanned string, and *flags
gives output flags.
If the value is <= UV_MAX
it is returned as a UV, the output flags are clear, and nothing is written to *result
. If the value is > UV_MAX
, grok_oct
returns UV_MAX
, sets PERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes an approximation of the correct value into *result
(which is an NV; or the approximation is discarded if result
is NULL).
If PERL_SCAN_ALLOW_UNDERSCORES
is set in *flags
then any or all pairs of digits may be separated from each other by a single underscore; also a single leading underscore is accepted.
The PERL_SCAN_DISALLOW_PREFIX
flag is always treated as being set for this function.
UV grok_oct(const char* start, STRLEN* len_p, I32* flags, NV *result)
isinfnan
Perl_isinfnan()
is a utility function that returns true if the NV argument is either an infinity or a NaN
, false otherwise. To test in more detail, use Perl_isinf()
and Perl_isnan()
.
This is also the logical inverse of Perl_isfinite().
bool isinfnan(NV nv)
my_atof
atof
(3), but properly works with Perl locale handling, accepting a dot radix character always, but also the current locale's radix character if and only if called from within the lexical scope of a Perl use locale
statement.
N.B. s
must be NUL terminated.
NV my_atof(const char *s)
my_strtod
This function is equivalent to the libc strtod() function, and is available even on platforms that lack plain strtod(). Its return value is the best available precision depending on platform capabilities and Configure options.
It properly handles the locale radix character, meaning it expects a dot except when called from within the scope of
, in which case the radix character should be that specified by the current locale.use locale
The synonym Strtod() may be used instead.
NV my_strtod(const char * const s, char ** e)
PERL_ABS
Typeless abs
or fabs
, etc. (The usage below indicates it is for integers, but it works for any type.) Use instead of these, since the C library ones force their argument to be what it is expecting, potentially leading to disaster. But also beware that this evaluates its argument twice, so no x++
.
int PERL_ABS(int x)
Perl_acos
Perl_asin
Perl_atan
Perl_atan2
Perl_ceil
Perl_cos
Perl_cosh
Perl_exp
Perl_floor
Perl_fmod
Perl_frexp
Perl_isfinite
Perl_isinf
Perl_isnan
Perl_ldexp
Perl_log
Perl_log10
Perl_modf
Perl_pow
Perl_sin
Perl_sinh
Perl_sqrt
Perl_tan
Perl_tanh
These perform the corresponding mathematical operation on the operand(s), using the libc function designed for the task that has just enough precision for an NV on this platform. If no such function with sufficient precision exists, the highest precision one available is used.
NV Perl_acos (NV x) NV Perl_asin (NV x) NV Perl_atan (NV x) NV Perl_atan2 (NV x, NV y) NV Perl_ceil (NV x) NV Perl_cos (NV x) NV Perl_cosh (NV x) NV Perl_exp (NV x) NV Perl_floor (NV x) NV Perl_fmod (NV x, NV y) NV Perl_frexp (NV x, int *exp) IV Perl_isfinite(NV x) IV Perl_isinf (NV x) IV Perl_isnan (NV x) NV Perl_ldexp (NV x, int exp) NV Perl_log (NV x) NV Perl_log10 (NV x) NV Perl_modf (NV x, NV *iptr) NV Perl_pow (NV x, NV y) NV Perl_sin (NV x) NV Perl_sinh (NV x) NV Perl_sqrt (NV x) NV Perl_tan (NV x) NV Perl_tanh (NV x)
Perl_signbit
NOTE: Perl_signbit
is experimental and may change or be removed without notice.
Return a non-zero integer if the sign bit on an NV is set, and 0 if it is not.
If Configure detects this system has a signbit()
that will work with our NVs, then we just use it via the #define
in perl.h. Otherwise, fall back on this implementation. The main use of this function is catching -0.0
.
Configure
notes: This function is called 'Perl_signbit'
instead of a plain 'signbit'
because it is easy to imagine a system having a signbit()
function or macro that doesn't happen to work with our particular choice of NVs. We shouldn't just re-#define
signbit
as Perl_signbit
and expect the standard system headers to be happy. Also, this is a no-context function (no pTHX_
) because Perl_signbit()
is usually re-#defined
in perl.h as a simple macro call to the system's signbit()
. Users should just always call Perl_signbit()
.
int Perl_signbit(NV f)
PL_hexdigit
This array, indexed by an integer, converts that value into the character that represents it. For example, if the input is 8, the return will be a string whose first character is '8'. What is actually returned is a pointer into a string. All you are interested in is the first character of that string. To get uppercase letters (for the values 10..15), add 16 to the index. Hence, PL_hexdigit[11]
is 'b'
, and PL_hexdigit[11+16]
is 'B'
. Adding 16 to an index whose representation is '0'..'9' yields the same as not adding 16. Indices outside the range 0..31 result in (bad) undedefined behavior.
READ_XDIGIT
Returns the value of an ASCII-range hex digit and advances the string pointer. Behaviour is only well defined when isXDIGIT(*str) is true.
U8 READ_XDIGIT(char str*)
scan_bin
For backwards compatibility. Use grok_bin
instead.
NV scan_bin(const char* start, STRLEN len, STRLEN* retlen)
scan_hex
For backwards compatibility. Use grok_hex
instead.
NV scan_hex(const char* start, STRLEN len, STRLEN* retlen)
scan_oct
For backwards compatibility. Use grok_oct
instead.
NV scan_oct(const char* start, STRLEN len, STRLEN* retlen)
seedDrand01
This symbol defines the macro to be used in seeding the random number generator (see "Drand01"
).
void seedDrand01(Rand_seed_t x)
Strtod
This is a synonym for "my_strtod".
NV Strtod(NN const char * const s, NULLOK char ** e)
alloccopstash
NOTE: alloccopstash
is experimental and may change or be removed without notice.
Available only under threaded builds, this function allocates an entry in PL_stashpad
for the stash passed to it.
PADOFFSET alloccopstash(HV *hv)
BINOP
Described in perlguts.
block_end
Handles compile-time scope exit. floor
is the savestack index returned by block_start
, and seq
is the body of the block. Returns the block, possibly modified.
OP* block_end(I32 floor, OP* seq)
block_start
Handles compile-time scope entry. Arranges for hints to be restored on block exit and also handles pad sequence numbers to make lexical variables scope right. Returns a savestack index for use with block_end
.
int block_start(int full)
ck_entersub_args_list
Performs the default fixup of the arguments part of an entersub
op tree. This consists of applying list context to each of the argument ops. This is the standard treatment used on a call marked with &
, or a method call, or a call through a subroutine reference, or any other call where the callee can't be identified at compile time, or a call where the callee has no prototype.
OP* ck_entersub_args_list(OP *entersubop)
ck_entersub_args_proto
Performs the fixup of the arguments part of an entersub
op tree based on a subroutine prototype. This makes various modifications to the argument ops, from applying context up to inserting refgen
ops, and checking the number and syntactic types of arguments, as directed by the prototype. This is the standard treatment used on a subroutine call, not marked with &
, where the callee can be identified at compile time and has a prototype.
protosv
supplies the subroutine prototype to be applied to the call. It may be a normal defined scalar, of which the string value will be used. Alternatively, for convenience, it may be a subroutine object (a CV*
that has been cast to SV*
) which has a prototype. The prototype supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of arguments, a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. In the error message, the callee is referred to by the name defined by the namegv
parameter.
OP* ck_entersub_args_proto(OP *entersubop, GV *namegv, SV *protosv)
ck_entersub_args_proto_or_list
Performs the fixup of the arguments part of an entersub
op tree either based on a subroutine prototype or using default list-context processing. This is the standard treatment used on a subroutine call, not marked with &
, where the callee can be identified at compile time.
protosv
supplies the subroutine prototype to be applied to the call, or indicates that there is no prototype. It may be a normal scalar, in which case if it is defined then the string value will be used as a prototype, and if it is undefined then there is no prototype. Alternatively, for convenience, it may be a subroutine object (a CV*
that has been cast to SV*
), of which the prototype will be used if it has one. The prototype (or lack thereof) supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of arguments, a valid op tree is returned anyway. The error is reflected in the parser state, normally resulting in a single exception at the top level of parsing which covers all the compilation errors that occurred. In the error message, the callee is referred to by the name defined by the namegv
parameter.
OP* ck_entersub_args_proto_or_list(OP *entersubop, GV *namegv, SV *protosv)
cv_const_sv
If cv
is a constant sub eligible for inlining, returns the constant value returned by the sub. Otherwise, returns NULL
.
Constant subs can be created with newCONSTSUB
or as described in "Constant Functions" in perlsub.
SV* cv_const_sv(const CV *const cv)
cv_get_call_checker
The original form of "cv_get_call_checker_flags", which does not return checker flags. When using a checker function returned by this function, it is only safe to call it with a genuine GV as its namegv
argument.
void cv_get_call_checker(CV *cv, Perl_call_checker *ckfun_p, SV **ckobj_p)
cv_get_call_checker_flags
Retrieves the function that will be used to fix up a call to cv
. Specifically, the function is applied to an entersub
op tree for a subroutine call, not marked with &
, where the callee can be identified at compile time as cv
.
The C-level function pointer is returned in *ckfun_p
, an SV argument for it is returned in *ckobj_p
, and control flags are returned in *ckflags_p
. The function is intended to be called in this manner:
entersubop = (*ckfun_p)(aTHX_ entersubop, namegv, (*ckobj_p));
In this call, entersubop
is a pointer to the entersub
op, which may be replaced by the check function, and namegv
supplies the name that should be used by the check function to refer to the callee of the entersub
op if it needs to emit any diagnostics. It is permitted to apply the check function in non-standard situations, such as to a call to a different subroutine or to a method call.
namegv
may not actually be a GV. If the CALL_CHECKER_REQUIRE_GV
bit is clear in *ckflags_p
, it is permitted to pass a CV or other SV instead, anything that can be used as the first argument to "cv_name". If the CALL_CHECKER_REQUIRE_GV
bit is set in *ckflags_p
then the check function requires namegv
to be a genuine GV.
By default, the check function is Perl_ck_entersub_args_proto_or_list, the SV parameter is cv
itself, and the CALL_CHECKER_REQUIRE_GV
flag is clear. This implements standard prototype processing. It can be changed, for a particular subroutine, by "cv_set_call_checker_flags".
If the CALL_CHECKER_REQUIRE_GV
bit is set in gflags
then it indicates that the caller only knows about the genuine GV version of namegv
, and accordingly the corresponding bit will always be set in *ckflags_p
, regardless of the check function's recorded requirements. If the CALL_CHECKER_REQUIRE_GV
bit is clear in gflags
then it indicates the caller knows about the possibility of passing something other than a GV as namegv
, and accordingly the corresponding bit may be either set or clear in *ckflags_p
, indicating the check function's recorded requirements.
gflags
is a bitset passed into cv_get_call_checker_flags
, in which only the CALL_CHECKER_REQUIRE_GV
bit currently has a defined meaning (for which see above). All other bits should be clear.
void cv_get_call_checker_flags(CV *cv, U32 gflags, Perl_call_checker *ckfun_p, SV **ckobj_p, U32 *ckflags_p)
cv_set_call_checker
The original form of "cv_set_call_checker_flags", which passes it the CALL_CHECKER_REQUIRE_GV
flag for backward-compatibility. The effect of that flag setting is that the check function is guaranteed to get a genuine GV as its namegv
argument.
void cv_set_call_checker(CV *cv, Perl_call_checker ckfun, SV *ckobj)
cv_set_call_checker_flags
Sets the function that will be used to fix up a call to cv
. Specifically, the function is applied to an entersub
op tree for a subroutine call, not marked with &
, where the callee can be identified at compile time as cv
.
The C-level function pointer is supplied in ckfun
, an SV argument for it is supplied in ckobj
, and control flags are supplied in ckflags
. The function should be defined like this:
STATIC OP * ckfun(pTHX_ OP *op, GV *namegv, SV *ckobj)
It is intended to be called in this manner:
entersubop = ckfun(aTHX_ entersubop, namegv, ckobj);
In this call, entersubop
is a pointer to the entersub
op, which may be replaced by the check function, and namegv
supplies the name that should be used by the check function to refer to the callee of the entersub
op if it needs to emit any diagnostics. It is permitted to apply the check function in non-standard situations, such as to a call to a different subroutine or to a method call.
namegv
may not actually be a GV. For efficiency, perl may pass a CV or other SV instead. Whatever is passed can be used as the first argument to "cv_name". You can force perl to pass a GV by including CALL_CHECKER_REQUIRE_GV
in the ckflags
.
ckflags
is a bitset, in which only the CALL_CHECKER_REQUIRE_GV
bit currently has a defined meaning (for which see above). All other bits should be clear.
The current setting for a particular CV can be retrieved by "cv_get_call_checker_flags".
void cv_set_call_checker_flags(CV *cv, Perl_call_checker ckfun, SV *ckobj, U32 ckflags)
LINKLIST
Given the root of an optree, link the tree in execution order using the op_next
pointers and return the first op executed. If this has already been done, it will not be redone, and o->op_next
will be returned. If o->op_next
is not already set, o
should be at least an UNOP
.
OP* LINKLIST(OP *o)
LISTOP
Described in perlguts.
LOGOP
Described in perlguts.
LOOP
Described in perlguts.
newASSIGNOP
Constructs, checks, and returns an assignment op. left
and right
supply the parameters of the assignment; they are consumed by this function and become part of the constructed op tree.
If optype
is OP_ANDASSIGN
, OP_ORASSIGN
, or OP_DORASSIGN
, then a suitable conditional optree is constructed. If optype
is the opcode of a binary operator, such as OP_BIT_OR
, then an op is constructed that performs the binary operation and assigns the result to the left argument. Either way, if optype
is non-zero then flags
has no effect.
If optype
is zero, then a plain scalar or list assignment is constructed. Which type of assignment it is is automatically determined. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 or 2 is automatically set as required.
OP* newASSIGNOP(I32 flags, OP* left, I32 optype, OP* right)
newATTRSUB
Construct a Perl subroutine, also performing some surrounding jobs.
This is the same as "newATTRSUB_x
" in perlintern with its o_is_gv
parameter set to FALSE. This means that if o
is null, the new sub will be anonymous; otherwise the name will be derived from o
in the way described (as with all other details) in "newATTRSUB_x
" in perlintern.
CV* newATTRSUB(I32 floor, OP *o, OP *proto, OP *attrs, OP *block)
newBINOP
Constructs, checks, and returns an op of any binary type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 or 2 is automatically set as required. first
and last
supply up to two ops to be the direct children of the binary op; they are consumed by this function and become part of the constructed op tree.
OP* newBINOP(I32 type, I32 flags, OP* first, OP* last)
newCONDOP
Constructs, checks, and returns a conditional-expression (cond_expr
) op. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. first
supplies the expression selecting between the two branches, and trueop
and falseop
supply the branches; they are consumed by this function and become part of the constructed op tree.
OP* newCONDOP(I32 flags, OP* first, OP* trueop, OP* falseop)
newCONSTSUB
Behaves like "newCONSTSUB_flags", except that name
is nul-terminated rather than of counted length, and no flags are set. (This means that name
is always interpreted as Latin-1.)
CV* newCONSTSUB(HV* stash, const char* name, SV* sv)
newCONSTSUB_flags
Construct a constant subroutine, also performing some surrounding jobs. A scalar constant-valued subroutine is eligible for inlining at compile-time, and in Perl code can be created by
. Other kinds of constant subroutine have other treatment.sub FOO () { 123 }
The subroutine will have an empty prototype and will ignore any arguments when called. Its constant behaviour is determined by sv
. If sv
is null, the subroutine will yield an empty list. If sv
points to a scalar, the subroutine will always yield that scalar. If sv
points to an array, the subroutine will always yield a list of the elements of that array in list context, or the number of elements in the array in scalar context. This function takes ownership of one counted reference to the scalar or array, and will arrange for the object to live as long as the subroutine does. If sv
points to a scalar then the inlining assumes that the value of the scalar will never change, so the caller must ensure that the scalar is not subsequently written to. If sv
points to an array then no such assumption is made, so it is ostensibly safe to mutate the array or its elements, but whether this is really supported has not been determined.
The subroutine will have CvFILE
set according to PL_curcop
. Other aspects of the subroutine will be left in their default state. The caller is free to mutate the subroutine beyond its initial state after this function has returned.
If name
is null then the subroutine will be anonymous, with its CvGV
referring to an __ANON__
glob. If name
is non-null then the subroutine will be named accordingly, referenced by the appropriate glob. name
is a string of length len
bytes giving a sigilless symbol name, in UTF-8 if flags
has the SVf_UTF8
bit set and in Latin-1 otherwise. The name may be either qualified or unqualified. If the name is unqualified then it defaults to being in the stash specified by stash
if that is non-null, or to PL_curstash
if stash
is null. The symbol is always added to the stash if necessary, with GV_ADDMULTI
semantics.
flags
should not have bits set other than SVf_UTF8
.
If there is already a subroutine of the specified name, then the new sub will replace the existing one in the glob. A warning may be generated about the redefinition.
If the subroutine has one of a few special names, such as BEGIN
or END
, then it will be claimed by the appropriate queue for automatic running of phase-related subroutines. In this case the relevant glob will be left not containing any subroutine, even if it did contain one before. Execution of the subroutine will likely be a no-op, unless sv
was a tied array or the caller modified the subroutine in some interesting way before it was executed. In the case of BEGIN
, the treatment is buggy: the sub will be executed when only half built, and may be deleted prematurely, possibly causing a crash.
The function returns a pointer to the constructed subroutine. If the sub is anonymous then ownership of one counted reference to the subroutine is transferred to the caller. If the sub is named then the caller does not get ownership of a reference. In most such cases, where the sub has a non-phase name, the sub will be alive at the point it is returned by virtue of being contained in the glob that names it. A phase-named subroutine will usually be alive by virtue of the reference owned by the phase's automatic run queue. A BEGIN
subroutine may have been destroyed already by the time this function returns, but currently bugs occur in that case before the caller gets control. It is the caller's responsibility to ensure that it knows which of these situations applies.
CV* newCONSTSUB_flags(HV* stash, const char* name, STRLEN len, U32 flags, SV* sv)
newDEFEROP
NOTE: newDEFEROP
is experimental and may change or be removed without notice.
Constructs and returns a deferred-block statement that implements the defer
semantics. The block
optree is consumed by this function and becomes part of the returned optree.
The flags
argument carries additional flags to set on the returned op, including the op_private
field.
OP* newDEFEROP(I32 flags, OP *block)
newFOROP
Constructs, checks, and returns an op tree expressing a foreach
loop (iteration through a list of values). This is a heavyweight loop, with structure that allows exiting the loop by last
and suchlike.
sv
optionally supplies the variable(s) that will be aliased to each item in turn; if null, it defaults to $_
. expr
supplies the list of values to iterate over. block
supplies the main body of the loop, and cont
optionally supplies a continue
block that operates as a second half of the body. All of these optree inputs are consumed by this function and become part of the constructed op tree.
flags
gives the eight bits of op_flags
for the leaveloop
op and, shifted up eight bits, the eight bits of op_private
for the leaveloop
op, except that (in both cases) some bits will be set automatically.
OP* newFOROP(I32 flags, OP* sv, OP* expr, OP* block, OP* cont)
newGIVENOP
Constructs, checks, and returns an op tree expressing a given
block. cond
supplies the expression to whose value $_
will be locally aliased, and block
supplies the body of the given
construct; they are consumed by this function and become part of the constructed op tree. defsv_off
must be zero (it used to identity the pad slot of lexical $_).
OP* newGIVENOP(OP* cond, OP* block, PADOFFSET defsv_off)
newGVOP
Constructs, checks, and returns an op of any type that involves an embedded reference to a GV. type
is the opcode. flags
gives the eight bits of op_flags
. gv
identifies the GV that the op should reference; calling this function does not transfer ownership of any reference to it.
OP* newGVOP(I32 type, I32 flags, GV* gv)
newLISTOP
Constructs, checks, and returns an op of any list type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically if required. first
and last
supply up to two ops to be direct children of the list op; they are consumed by this function and become part of the constructed op tree.
For most list operators, the check function expects all the kid ops to be present already, so calling newLISTOP(OP_JOIN, ...)
(e.g.) is not appropriate. What you want to do in that case is create an op of type OP_LIST
, append more children to it, and then call "op_convert_list". See "op_convert_list" for more information.
OP* newLISTOP(I32 type, I32 flags, OP* first, OP* last)
newLOGOP
Constructs, checks, and returns a logical (flow control) op. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. first
supplies the expression controlling the flow, and other
supplies the side (alternate) chain of ops; they are consumed by this function and become part of the constructed op tree.
OP* newLOGOP(I32 optype, I32 flags, OP *first, OP *other)
newLOOPEX
Constructs, checks, and returns a loop-exiting op (such as goto
or last
). type
is the opcode. label
supplies the parameter determining the target of the op; it is consumed by this function and becomes part of the constructed op tree.
OP* newLOOPEX(I32 type, OP* label)
newLOOPOP
Constructs, checks, and returns an op tree expressing a loop. This is only a loop in the control flow through the op tree; it does not have the heavyweight loop structure that allows exiting the loop by last
and suchlike. flags
gives the eight bits of op_flags
for the top-level op, except that some bits will be set automatically as required. expr
supplies the expression controlling loop iteration, and block
supplies the body of the loop; they are consumed by this function and become part of the constructed op tree. debuggable
is currently unused and should always be 1.
OP* newLOOPOP(I32 flags, I32 debuggable, OP* expr, OP* block)
newMETHOP
Constructs, checks, and returns an op of method type with a method name evaluated at runtime. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. dynamic_meth
supplies an op which evaluates method name; it is consumed by this function and become part of the constructed op tree. Supported optypes: OP_METHOD
.
OP* newMETHOP(I32 type, I32 flags, OP* dynamic_meth)
newMETHOP_named
Constructs, checks, and returns an op of method type with a constant method name. type
is the opcode. flags
gives the eight bits of op_flags
, and, shifted up eight bits, the eight bits of op_private
. const_meth
supplies a constant method name; it must be a shared COW string. Supported optypes: OP_METHOD_NAMED
.
OP* newMETHOP_named(I32 type, I32 flags, SV* const_meth)
newNULLLIST
Constructs, checks, and returns a new stub
op, which represents an empty list expression.
OP* newNULLLIST()
newOP
Constructs, checks, and returns an op of any base type (any type that has no extra fields). type
is the opcode. flags
gives the eight bits of op_flags
, and, shifted up eight bits, the eight bits of op_private
.
OP* newOP(I32 optype, I32 flags)
newPADOP
Constructs, checks, and returns an op of any type that involves a reference to a pad element. type
is the opcode. flags
gives the eight bits of op_flags
. A pad slot is automatically allocated, and is populated with sv
; this function takes ownership of one reference to it.
This function only exists if Perl has been compiled to use ithreads.
OP* newPADOP(I32 type, I32 flags, SV* sv)
newPMOP
Constructs, checks, and returns an op of any pattern matching type. type
is the opcode. flags
gives the eight bits of op_flags
and, shifted up eight bits, the eight bits of op_private
.
OP* newPMOP(I32 type, I32 flags)
newPVOP
Constructs, checks, and returns an op of any type that involves an embedded C-level pointer (PV). type
is the opcode. flags
gives the eight bits of op_flags
. pv
supplies the C-level pointer. Depending on the op type, the memory referenced by pv
may be freed when the op is destroyed. If the op is of a freeing type, pv
must have been allocated using PerlMemShared_malloc
.
OP* newPVOP(I32 type, I32 flags, char* pv)
newRANGE
Constructs and returns a range
op, with subordinate flip
and flop
ops. flags
gives the eight bits of op_flags
for the flip
op and, shifted up eight bits, the eight bits of op_private
for both the flip
and range
ops, except that the bit with value 1 is automatically set. left
and right
supply the expressions controlling the endpoints of the range; they are consumed by this function and become part of the constructed op tree.
OP* newRANGE(I32 flags, OP* left, OP* right)
newSLICEOP
Constructs, checks, and returns an lslice
(list slice) op. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 or 2 is automatically set as required. listval
and subscript
supply the parameters of the slice; they are consumed by this function and become part of the constructed op tree.
OP* newSLICEOP(I32 flags, OP* subscript, OP* listop)
newSTATEOP
Constructs a state op (COP). The state op is normally a nextstate
op, but will be a dbstate
op if debugging is enabled for currently-compiled code. The state op is populated from PL_curcop
(or PL_compiling
). If label
is non-null, it supplies the name of a label to attach to the state op; this function takes ownership of the memory pointed at by label
, and will free it. flags
gives the eight bits of op_flags
for the state op.
If o
is null, the state op is returned. Otherwise the state op is combined with o
into a lineseq
list op, which is returned. o
is consumed by this function and becomes part of the returned op tree.
OP* newSTATEOP(I32 flags, char* label, OP* o)
newSUB
Like "newATTRSUB"
, but without attributes.
CV* newSUB(I32 floor, OP* o, OP* proto, OP* block)
newSVOP
Constructs, checks, and returns an op of any type that involves an embedded SV. type
is the opcode. flags
gives the eight bits of op_flags
. sv
gives the SV to embed in the op; this function takes ownership of one reference to it.
OP* newSVOP(I32 type, I32 flags, SV* sv)
newTRYCATCHOP
NOTE: newTRYCATCHOP
is experimental and may change or be removed without notice.
Constructs and returns a conditional execution statement that implements the try
/catch
semantics. First the op tree in tryblock
is executed, inside a context that traps exceptions. If an exception occurs then the optree in catchblock
is executed, with the trapped exception set into the lexical variable given by catchvar
(which must be an op of type OP_PADSV
). All the optrees are consumed by this function and become part of the returned op tree.
The flags
argument is currently ignored.
OP* newTRYCATCHOP(I32 flags, OP* tryblock, OP *catchvar, OP* catchblock)
newUNOP
Constructs, checks, and returns an op of any unary type. type
is the opcode. flags
gives the eight bits of op_flags
, except that OPf_KIDS
will be set automatically if required, and, shifted up eight bits, the eight bits of op_private
, except that the bit with value 1 is automatically set. first
supplies an optional op to be the direct child of the unary op; it is consumed by this function and become part of the constructed op tree.
OP* newUNOP(I32 type, I32 flags, OP* first)
newUNOP_AUX
Similar to newUNOP
, but creates an UNOP_AUX
struct instead, with op_aux
initialised to aux
OP* newUNOP_AUX(I32 type, I32 flags, OP* first, UNOP_AUX_item *aux)
newWHENOP
Constructs, checks, and returns an op tree expressing a when
block. cond
supplies the test expression, and block
supplies the block that will be executed if the test evaluates to true; they are consumed by this function and become part of the constructed op tree. cond
will be interpreted DWIMically, often as a comparison against $_
, and may be null to generate a default
block.
OP* newWHENOP(OP* cond, OP* block)
newWHILEOP
Constructs, checks, and returns an op tree expressing a while
loop. This is a heavyweight loop, with structure that allows exiting the loop by last
and suchlike.
loop
is an optional preconstructed enterloop
op to use in the loop; if it is null then a suitable op will be constructed automatically. expr
supplies the loop's controlling expression. block
supplies the main body of the loop, and cont
optionally supplies a continue
block that operates as a second half of the body. All of these optree inputs are consumed by this function and become part of the constructed op tree.
flags
gives the eight bits of op_flags
for the leaveloop
op and, shifted up eight bits, the eight bits of op_private
for the leaveloop
op, except that (in both cases) some bits will be set automatically. debuggable
is currently unused and should always be 1. has_my
can be supplied as true to force the loop body to be enclosed in its own scope.
OP* newWHILEOP(I32 flags, I32 debuggable, LOOP* loop, OP* expr, OP* block, OP* cont, I32 has_my)
newXS
Used by xsubpp
to hook up XSUBs as Perl subs. filename
needs to be static storage, as it is used directly as CvFILE(), without a copy being made.
OA_BASEOP
OA_BINOP
OA_COP
OA_LISTOP
OA_LOGOP
OA_PADOP
OA_PMOP
OA_PVOP_OR_SVOP
OA_SVOP
OA_UNOP
OA_LOOP
Described in perlguts.
OP
Described in perlguts.
op_append_elem
Append an item to the list of ops contained directly within a list-type op, returning the lengthened list. first
is the list-type op, and last
is the op to append to the list. optype
specifies the intended opcode for the list. If first
is not already a list of the right type, it will be upgraded into one. If either first
or last
is null, the other is returned unchanged.
OP* op_append_elem(I32 optype, OP* first, OP* last)
op_append_list
Concatenate the lists of ops contained directly within two list-type ops, returning the combined list. first
and last
are the list-type ops to concatenate. optype
specifies the intended opcode for the list. If either first
or last
is not already a list of the right type, it will be upgraded into one. If either first
or last
is null, the other is returned unchanged.
OP* op_append_list(I32 optype, OP* first, OP* last)
OP_CLASS
Return the class of the provided OP: that is, which of the *OP structures it uses. For core ops this currently gets the information out of PL_opargs
, which does not always accurately reflect the type used; in v5.26 onwards, see also the function "op_class"
which can do a better job of determining the used type.
For custom ops the type is returned from the registration, and it is up to the registree to ensure it is accurate. The value returned will be one of the OA_
* constants from op.h.
U32 OP_CLASS(OP *o)
op_contextualize
Applies a syntactic context to an op tree representing an expression. o
is the op tree, and context
must be G_SCALAR
, G_LIST
, or G_VOID
to specify the context to apply. The modified op tree is returned.
OP* op_contextualize(OP* o, I32 context)
op_convert_list
Converts o
into a list op if it is not one already, and then converts it into the specified type
, calling its check function, allocating a target if it needs one, and folding constants.
A list-type op is usually constructed one kid at a time via newLISTOP
, op_prepend_elem
and op_append_elem
. Then finally it is passed to op_convert_list
to make it the right type.
OP* op_convert_list(I32 optype, I32 flags, OP* o)
op_free
Free an op and its children. Only use this when an op is no longer linked to from any optree.
void op_free(OP* arg)
OpLASTSIB_set
Marks o
as having no further siblings and marks o as having the specified parent. See also "OpMORESIB_set"
and OpMAYBESIB_set
. For a higher-level interface, see "op_sibling_splice"
.
void OpLASTSIB_set(OP *o, OP *parent)
op_linklist
This function is the implementation of the "LINKLIST" macro. It should not be called directly.
OP* op_linklist(OP *o)
op_lvalue
NOTE: op_lvalue
is experimental and may change or be removed without notice.
Propagate lvalue ("modifiable") context to an op and its children. type
represents the context type, roughly based on the type of op that would do the modifying, although local()
is represented by OP_NULL
, because it has no op type of its own (it is signalled by a flag on the lvalue op).
This function detects things that can't be modified, such as $x+1
, and generates errors for them. For example, $x+1 = 2
would cause it to be called with an op of type OP_ADD
and a type
argument of OP_SASSIGN
.
It also flags things that need to behave specially in an lvalue context, such as $$x = 5
which might have to vivify a reference in $x
.
OP* op_lvalue(OP* o, I32 type)
OpMAYBESIB_set
Conditionally does OpMORESIB_set
or OpLASTSIB_set
depending on whether sib
is non-null. For a higher-level interface, see "op_sibling_splice"
.
void OpMAYBESIB_set(OP *o, OP *sib, OP *parent)
OpMORESIB_set
Sets the sibling of o
to the non-zero value sib
. See also "OpLASTSIB_set"
and "OpMAYBESIB_set"
. For a higher-level interface, see "op_sibling_splice"
.
void OpMORESIB_set(OP *o, OP *sib)
OP_NAME
Return the name of the provided OP. For core ops this looks up the name from the op_type; for custom ops from the op_ppaddr.
const char * OP_NAME(OP *o)
op_null
Neutralizes an op when it is no longer needed, but is still linked to from other ops.
void op_null(OP* o)
op_parent
Returns the parent OP of o
, if it has a parent. Returns NULL
otherwise.
OP* op_parent(OP *o)
op_prepend_elem
Prepend an item to the list of ops contained directly within a list-type op, returning the lengthened list. first
is the op to prepend to the list, and last
is the list-type op. optype
specifies the intended opcode for the list. If last
is not already a list of the right type, it will be upgraded into one. If either first
or last
is null, the other is returned unchanged.
OP* op_prepend_elem(I32 optype, OP* first, OP* last)
op_scope
NOTE: op_scope
is experimental and may change or be removed without notice.
Wraps up an op tree with some additional ops so that at runtime a dynamic scope will be created. The original ops run in the new dynamic scope, and then, provided that they exit normally, the scope will be unwound. The additional ops used to create and unwind the dynamic scope will normally be an enter
/leave
pair, but a scope
op may be used instead if the ops are simple enough to not need the full dynamic scope structure.
OP* op_scope(OP* o)
op_sibling_splice
A general function for editing the structure of an existing chain of op_sibling nodes. By analogy with the perl-level splice()
function, allows you to delete zero or more sequential nodes, replacing them with zero or more different nodes. Performs the necessary op_first/op_last housekeeping on the parent node and op_sibling manipulation on the children. The last deleted node will be marked as the last node by updating the op_sibling/op_sibparent or op_moresib field as appropriate.
Note that op_next is not manipulated, and nodes are not freed; that is the responsibility of the caller. It also won't create a new list op for an empty list etc; use higher-level functions like op_append_elem() for that.
parent
is the parent node of the sibling chain. It may passed as NULL
if the splicing doesn't affect the first or last op in the chain.
start
is the node preceding the first node to be spliced. Node(s) following it will be deleted, and ops will be inserted after it. If it is NULL
, the first node onwards is deleted, and nodes are inserted at the beginning.
del_count
is the number of nodes to delete. If zero, no nodes are deleted. If -1 or greater than or equal to the number of remaining kids, all remaining kids are deleted.
insert
is the first of a chain of nodes to be inserted in place of the nodes. If NULL
, no nodes are inserted.
The head of the chain of deleted ops is returned, or NULL
if no ops were deleted.
For example:
action before after returns ------ ----- ----- ------- P P splice(P, A, 2, X-Y-Z) | | B-C A-B-C-D A-X-Y-Z-D P P splice(P, NULL, 1, X-Y) | | A A-B-C-D X-Y-B-C-D P P splice(P, NULL, 3, NULL) | | A-B-C A-B-C-D D P P splice(P, B, 0, X-Y) | | NULL A-B-C-D A-B-X-Y-C-D
For lower-level direct manipulation of op_sibparent
and op_moresib
, see "OpMORESIB_set"
, "OpLASTSIB_set"
, "OpMAYBESIB_set"
.
OP* op_sibling_splice(OP *parent, OP *start, int del_count, OP* insert)
OP_TYPE_IS
Returns true if the given OP is not a NULL
pointer and if it is of the given type.
The negation of this macro, OP_TYPE_ISNT
is also available as well as OP_TYPE_IS_NN
and OP_TYPE_ISNT_NN
which elide the NULL pointer check.
bool OP_TYPE_IS(OP *o, Optype type)
OP_TYPE_IS_OR_WAS
Returns true if the given OP is not a NULL pointer and if it is of the given type or used to be before being replaced by an OP of type OP_NULL.
The negation of this macro, OP_TYPE_ISNT_AND_WASNT
is also available as well as OP_TYPE_IS_OR_WAS_NN
and OP_TYPE_ISNT_AND_WASNT_NN
which elide the NULL
pointer check.
bool OP_TYPE_IS_OR_WAS(OP *o, Optype type)
op_wrap_finally
NOTE: op_wrap_finally
is experimental and may change or be removed without notice.
Wraps the given block
optree fragment in its own scoped block, arranging for the finally
optree fragment to be invoked when leaving that block for any reason. Both optree fragments are consumed and the combined result is returned.
OP* op_wrap_finally(OP *block, OP *finally)
peep_t
Described in perlguts.
Perl_cpeep_t
Described in perlguts.
PL_opfreehook
When non-NULL
, the function pointed by this variable will be called each time an OP is freed with the corresponding OP as the argument. This allows extensions to free any extra attribute they have locally attached to an OP. It is also assured to first fire for the parent OP and then for its kids.
When you replace this variable, it is considered a good practice to store the possibly previously installed hook and that you recall it inside your own.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
Perl_ophook_t PL_opfreehook
PL_peepp
Pointer to the per-subroutine peephole optimiser. This is a function that gets called at the end of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform fixups of some ops and to perform small-scale optimisations. The function is called once for each subroutine that is compiled, and is passed, as sole parameter, a pointer to the op that is the entry point to the subroutine. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping the existing optimiser. The basic way to do this can be seen in "Compile pass 3: peephole optimization" in perlguts. If the new code wishes to operate on ops throughout the subroutine's structure, rather than just at the top level, it is likely to be more convenient to wrap the "PL_rpeepp" hook.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
peep_t PL_peepp
PL_rpeepp
Pointer to the recursive peephole optimiser. This is a function that gets called at the end of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform fixups of some ops and to perform small-scale optimisations. The function is called once for each chain of ops linked through their op_next
fields; it is recursively called to handle each side chain. It is passed, as sole parameter, a pointer to the op that is at the head of the chain. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping the existing optimiser. The basic way to do this can be seen in "Compile pass 3: peephole optimization" in perlguts. If the new code wishes to operate only on ops at a subroutine's top level, rather than throughout the structure, it is likely to be more convenient to wrap the "PL_peepp" hook.
On threaded perls, each thread has an independent copy of this variable; each initialized at creation time with the current value of the creating thread's copy.
peep_t PL_rpeepp
PMOP
Described in perlguts.
rv2cv_op_cv
Examines an op, which is expected to identify a subroutine at runtime, and attempts to determine at compile time which subroutine it identifies. This is normally used during Perl compilation to determine whether a prototype can be applied to a function call. cvop
is the op being considered, normally an rv2cv
op. A pointer to the identified subroutine is returned, if it could be determined statically, and a null pointer is returned if it was not possible to determine statically.
Currently, the subroutine can be identified statically if the RV that the rv2cv
is to operate on is provided by a suitable gv
or const
op. A gv
op is suitable if the GV's CV slot is populated. A const
op is suitable if the constant value must be an RV pointing to a CV. Details of this process may change in future versions of Perl. If the rv2cv
op has the OPpENTERSUB_AMPER
flag set then no attempt is made to identify the subroutine statically: this flag is used to suppress compile-time magic on a subroutine call, forcing it to use default runtime behaviour.
If flags
has the bit RV2CVOPCV_MARK_EARLY
set, then the handling of a GV reference is modified. If a GV was examined and its CV slot was found to be empty, then the gv
op has the OPpEARLY_CV
flag set. If the op is not optimised away, and the CV slot is later populated with a subroutine having a prototype, that flag eventually triggers the warning "called too early to check prototype".
If flags
has the bit RV2CVOPCV_RETURN_NAME_GV
set, then instead of returning a pointer to the subroutine it returns a pointer to the GV giving the most appropriate name for the subroutine in this context. Normally this is just the CvGV
of the subroutine, but for an anonymous (CvANON
) subroutine that is referenced through a GV it will be the referencing GV. The resulting GV*
is cast to CV*
to be returned. A null pointer is returned as usual if there is no statically-determinable subroutine.
CV* rv2cv_op_cv(OP *cvop, U32 flags)
UNOP
Described in perlguts.
XOP
Described in perlguts.
pack_cat
DEPRECATED!
It is planned to remove pack_cat
from a future release of Perl. Do not use it for new code; remove it from existing code.
The engine implementing pack()
Perl function. Note: parameters next_in_list
and flags
are not used. This call should not be used; use "packlist"
instead.
void pack_cat(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist, SV ***next_in_list, U32 flags)
packlist
The engine implementing pack()
Perl function.
void packlist(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist)
unpack_str
DEPRECATED!
It is planned to remove unpack_str
from a future release of Perl. Do not use it for new code; remove it from existing code.
The engine implementing unpack()
Perl function. Note: parameters strbeg
, new_s
and ocnt
are not used. This call should not be used, use unpackstring
instead.
SSize_t unpack_str(const char *pat, const char *patend, const char *s, const char *strbeg, const char *strend, char **new_s, I32 ocnt, U32 flags)
unpackstring
The engine implementing the unpack()
Perl function.
Using the template pat..patend
, this function unpacks the string s..strend
into a number of mortal SVs, which it pushes onto the perl argument (@_
) stack (so you will need to issue a PUTBACK
before and SPAGAIN
after the call to this function). It returns the number of pushed elements.
The strend
and patend
pointers should point to the byte following the last character of each string.
Although this function returns its values on the perl argument stack, it doesn't take any parameters from that stack (and thus in particular there's no need to do a PUSHMARK
before calling it, unlike "call_pv" for example).
SSize_t unpackstring(const char *pat, const char *patend, const char *s, const char *strend, U32 flags)
CvPADLIST
NOTE: CvPADLIST
is experimental and may change or be removed without notice.
CV's can have CvPADLIST(cv) set to point to a PADLIST. This is the CV's scratchpad, which stores lexical variables and opcode temporary and per-thread values.
For these purposes "formats" are a kind-of CV; eval""s are too (except they're not callable at will and are always thrown away after the eval"" is done executing). Require'd files are simply evals without any outer lexical scope.
XSUBs do not have a CvPADLIST
. dXSTARG
fetches values from PL_curpad
, but that is really the callers pad (a slot of which is allocated by every entersub). Do not get or set CvPADLIST
if a CV is an XSUB (as determined by CvISXSUB()
), CvPADLIST
slot is reused for a different internal purpose in XSUBs.
The PADLIST has a C array where pads are stored.
The 0th entry of the PADLIST is a PADNAMELIST which represents the "names" or rather the "static type information" for lexicals. The individual elements of a PADNAMELIST are PADNAMEs. Future refactorings might stop the PADNAMELIST from being stored in the PADLIST's array, so don't rely on it. See "PadlistNAMES".
The CvDEPTH'th entry of a PADLIST is a PAD (an AV) which is the stack frame at that depth of recursion into the CV. The 0th slot of a frame AV is an AV which is @_
. Other entries are storage for variables and op targets.
Iterating over the PADNAMELIST iterates over all possible pad items. Pad slots for targets (SVs_PADTMP
) and GVs end up having &PL_padname_undef "names", while slots for constants have &PL_padname_const
"names" (see "pad_alloc"
). That &PL_padname_undef
and &PL_padname_const
are used is an implementation detail subject to change. To test for them, use !PadnamePV(name)
and
, respectively.PadnamePV(name) && !PadnameLEN(name)
Only my
/our
variable slots get valid names. The rest are op targets/GVs/constants which are statically allocated or resolved at compile time. These don't have names by which they can be looked up from Perl code at run time through eval"" the way my
/our
variables can be. Since they can't be looked up by "name" but only by their index allocated at compile time (which is usually in PL_op->op_targ
), wasting a name SV for them doesn't make sense.
The pad names in the PADNAMELIST have their PV holding the name of the variable. The COP_SEQ_RANGE_LOW
and _HIGH
fields form a range (low+1..high inclusive) of cop_seq numbers for which the name is valid. During compilation, these fields may hold the special value PERL_PADSEQ_INTRO to indicate various stages:
COP_SEQ_RANGE_LOW _HIGH ----------------- ----- PERL_PADSEQ_INTRO 0 variable not yet introduced: { my ($x valid-seq# PERL_PADSEQ_INTRO variable in scope: { my ($x); valid-seq# valid-seq# compilation of scope complete: { my ($x); .... }
When a lexical var hasn't yet been introduced, it already exists from the perspective of duplicate declarations, but not for variable lookups, e.g.
my ($x, $x); # '"my" variable $x masks earlier declaration' my $x = $x; # equal to my $x = $::x;
For typed lexicals PadnameTYPE
points at the type stash. For our
lexicals, PadnameOURSTASH
points at the stash of the associated global (so that duplicate our
declarations in the same package can be detected). PadnameGEN
is sometimes used to store the generation number during compilation.
If PadnameOUTER
is set on the pad name, then that slot in the frame AV is a REFCNT'ed reference to a lexical from "outside". Such entries are sometimes referred to as 'fake'. In this case, the name does not use 'low' and 'high' to store a cop_seq range, since it is in scope throughout. Instead 'high' stores some flags containing info about the real lexical (is it declared in an anon, and is it capable of being instantiated multiple times?), and for fake ANONs, 'low' contains the index within the parent's pad where the lexical's value is stored, to make cloning quicker.
If the 'name' is &
the corresponding entry in the PAD is a CV representing a possible closure.
Note that formats are treated as anon subs, and are cloned each time write is called (if necessary).
The flag SVs_PADSTALE
is cleared on lexicals each time the my()
is executed, and set on scope exit. This allows the "Variable $x is not available"
warning to be generated in evals, such as
{ my $x = 1; sub f { eval '$x'} } f();
For state vars, SVs_PADSTALE
is overloaded to mean 'not yet initialised', but this internal state is stored in a separate pad entry.
PADLIST * CvPADLIST(CV *cv)
pad_add_name_pvs
Exactly like "pad_add_name_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_add_name_pvs("name", U32 flags, HV *typestash, HV *ourstash)
PadARRAY
NOTE: PadARRAY
is experimental and may change or be removed without notice.
The C array of pad entries.
SV ** PadARRAY(PAD * pad)
pad_compname_type
DEPRECATED!
It is planned to remove pad_compname_type
from a future release of Perl. Do not use it for new code; remove it from existing code.
Looks up the type of the lexical variable at position po
in the currently-compiling pad. If the variable is typed, the stash of the class to which it is typed is returned. If not, NULL
is returned.
Use "PAD_COMPNAME_TYPE
" in perlintern instead.
HV* pad_compname_type(const PADOFFSET po)
pad_findmy_pvs
Exactly like "pad_findmy_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_findmy_pvs("name", U32 flags)
PadlistARRAY
NOTE: PadlistARRAY
is experimental and may change or be removed without notice.
The C array of a padlist, containing the pads. Only subscript it with numbers >= 1, as the 0th entry is not guaranteed to remain usable.
PAD ** PadlistARRAY(PADLIST * padlist)
PadlistMAX
NOTE: PadlistMAX
is experimental and may change or be removed without notice.
The index of the last allocated space in the padlist. Note that the last pad may be in an earlier slot. Any entries following it will be NULL
in that case.
SSize_t PadlistMAX(PADLIST * padlist)
PadlistNAMES
NOTE: PadlistNAMES
is experimental and may change or be removed without notice.
The names associated with pad entries.
PADNAMELIST * PadlistNAMES(PADLIST * padlist)
PadlistNAMESARRAY
NOTE: PadlistNAMESARRAY
is experimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadlistNAMESARRAY(PADLIST * padlist)
PadlistNAMESMAX
NOTE: PadlistNAMESMAX
is experimental and may change or be removed without notice.
The index of the last pad name.
SSize_t PadlistNAMESMAX(PADLIST * padlist)
PadlistREFCNT
NOTE: PadlistREFCNT
is experimental and may change or be removed without notice.
The reference count of the padlist. Currently this is always 1.
U32 PadlistREFCNT(PADLIST * padlist)
PadMAX
NOTE: PadMAX
is experimental and may change or be removed without notice.
The index of the last pad entry.
SSize_t PadMAX(PAD * pad)
PadnameLEN
NOTE: PadnameLEN
is experimental and may change or be removed without notice.
The length of the name.
STRLEN PadnameLEN(PADNAME * pn)
PadnamelistARRAY
NOTE: PadnamelistARRAY
is experimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadnamelistARRAY(PADNAMELIST * pnl)
PadnamelistMAX
NOTE: PadnamelistMAX
is experimental and may change or be removed without notice.
The index of the last pad name.
SSize_t PadnamelistMAX(PADNAMELIST * pnl)
PadnamelistREFCNT
NOTE: PadnamelistREFCNT
is experimental and may change or be removed without notice.
The reference count of the pad name list.
SSize_t PadnamelistREFCNT(PADNAMELIST * pnl)
PadnamelistREFCNT_dec
NOTE: PadnamelistREFCNT_dec
is experimental and may change or be removed without notice.
Lowers the reference count of the pad name list.
void PadnamelistREFCNT_dec(PADNAMELIST * pnl)
PadnamePV
NOTE: PadnamePV
is experimental and may change or be removed without notice.
The name stored in the pad name struct. This returns NULL
for a target slot.
char * PadnamePV(PADNAME * pn)
PadnameREFCNT
NOTE: PadnameREFCNT
is experimental and may change or be removed without notice.
The reference count of the pad name.
SSize_t PadnameREFCNT(PADNAME * pn)
PadnameREFCNT_dec
NOTE: PadnameREFCNT_dec
is experimental and may change or be removed without notice.
Lowers the reference count of the pad name.
void PadnameREFCNT_dec(PADNAME * pn)
PadnameSV
NOTE: PadnameSV
is experimental and may change or be removed without notice.
Returns the pad name as a mortal SV.
SV * PadnameSV(PADNAME * pn)
PadnameUTF8
NOTE: PadnameUTF8
is experimental and may change or be removed without notice.
Whether PadnamePV is in UTF-8. Currently, this is always true.
bool PadnameUTF8(PADNAME * pn)
pad_new
Create a new padlist, updating the global variables for the currently-compiling padlist to point to the new padlist. The following flags can be OR'ed together:
padnew_CLONE this pad is for a cloned CV padnew_SAVE save old globals on the save stack padnew_SAVESUB also save extra stuff for start of sub
PADLIST* pad_new(int flags)
PL_comppad
NOTE: PL_comppad
is experimental and may change or be removed without notice.
During compilation, this points to the array containing the values part of the pad for the currently-compiling code. (At runtime a CV may have many such value arrays; at compile time just one is constructed.) At runtime, this points to the array containing the currently-relevant values for the pad for the currently-executing code.
PL_comppad_name
NOTE: PL_comppad_name
is experimental and may change or be removed without notice.
During compilation, this points to the array containing the names part of the pad for the currently-compiling code.
PL_curpad
NOTE: PL_curpad
is experimental and may change or be removed without notice.
Points directly to the body of the "PL_comppad" array. (I.e., this is PadARRAY(PL_comppad)
.)
SVs_PADMY
DEPRECATED!
It is planned to remove SVs_PADMY
from a future release of Perl. Do not use it for new code; remove it from existing code.
Described in perlguts.
SVs_PADTMP
Described in perlguts.
GRPASSWD
This symbol, if defined, indicates to the C program that struct group
in grp.h contains gr_passwd
.
HAS_ENDGRENT
This symbol, if defined, indicates that the getgrent routine is available for finalizing sequential access of the group database.
HAS_ENDGRENT_R
This symbol, if defined, indicates that the endgrent_r
routine is available to endgrent re-entrantly.
HAS_ENDPWENT
This symbol, if defined, indicates that the endpwent
routine is available for finalizing sequential access of the passwd database.
HAS_ENDPWENT_R
This symbol, if defined, indicates that the endpwent_r
routine is available to endpwent re-entrantly.
HAS_GETGRENT
This symbol, if defined, indicates that the getgrent
routine is available for sequential access of the group database.
HAS_GETGRENT_R
This symbol, if defined, indicates that the getgrent_r
routine is available to getgrent re-entrantly.
HAS_GETPWENT
This symbol, if defined, indicates that the getpwent
routine is available for sequential access of the passwd database. If this is not available, the older getpw()
function may be available.
HAS_GETPWENT_R
This symbol, if defined, indicates that the getpwent_r
routine is available to getpwent re-entrantly.
HAS_SETGRENT
This symbol, if defined, indicates that the setgrent
routine is available for initializing sequential access of the group database.
HAS_SETGRENT_R
This symbol, if defined, indicates that the setgrent_r
routine is available to setgrent re-entrantly.
HAS_SETPWENT
This symbol, if defined, indicates that the setpwent
routine is available for initializing sequential access of the passwd database.
HAS_SETPWENT_R
This symbol, if defined, indicates that the setpwent_r
routine is available to setpwent re-entrantly.
CRYPT_R_PROTO
This symbol encodes the prototype of crypt_r
. It is zero if d_crypt_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_crypt_r
is defined.
CTERMID_R_PROTO
This symbol encodes the prototype of ctermid_r
. It is zero if d_ctermid_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_ctermid_r
is defined.
DRAND48_R_PROTO
This symbol encodes the prototype of drand48_r
. It is zero if d_drand48_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_drand48_r
is defined.
ENDGRENT_R_PROTO
This symbol encodes the prototype of endgrent_r
. It is zero if d_endgrent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endgrent_r
is defined.
ENDHOSTENT_R_PROTO
This symbol encodes the prototype of endhostent_r
. It is zero if d_endhostent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endhostent_r
is defined.
ENDNETENT_R_PROTO
This symbol encodes the prototype of endnetent_r
. It is zero if d_endnetent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endnetent_r
is defined.
ENDPROTOENT_R_PROTO
This symbol encodes the prototype of endprotoent_r
. It is zero if d_endprotoent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endprotoent_r
is defined.
ENDPWENT_R_PROTO
This symbol encodes the prototype of endpwent_r
. It is zero if d_endpwent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endpwent_r
is defined.
ENDSERVENT_R_PROTO
This symbol encodes the prototype of endservent_r
. It is zero if d_endservent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_endservent_r
is defined.
GDBMNDBM_H_USES_PROTOTYPES
This symbol, if defined, indicates that gdbm/ndbm.h uses real ANSI
C prototypes instead of K&R style function declarations without any parameter information. While ANSI
C prototypes are supported in C++, K&R style function declarations will yield errors.
GDBM_NDBM_H_USES_PROTOTYPES
This symbol, if defined, indicates that <gdbm-ndbm.h> uses real ANSI
C prototypes instead of K&R style function declarations without any parameter information. While ANSI
C prototypes are supported in C++, K&R style function declarations will yield errors.
GETGRENT_R_PROTO
This symbol encodes the prototype of getgrent_r
. It is zero if d_getgrent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getgrent_r
is defined.
GETGRGID_R_PROTO
This symbol encodes the prototype of getgrgid_r
. It is zero if d_getgrgid_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getgrgid_r
is defined.
GETGRNAM_R_PROTO
This symbol encodes the prototype of getgrnam_r
. It is zero if d_getgrnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getgrnam_r
is defined.
GETHOSTBYADDR_R_PROTO
This symbol encodes the prototype of gethostbyaddr_r
. It is zero if d_gethostbyaddr_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gethostbyaddr_r
is defined.
GETHOSTBYNAME_R_PROTO
This symbol encodes the prototype of gethostbyname_r
. It is zero if d_gethostbyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gethostbyname_r
is defined.
GETHOSTENT_R_PROTO
This symbol encodes the prototype of gethostent_r
. It is zero if d_gethostent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gethostent_r
is defined.
GETLOGIN_R_PROTO
This symbol encodes the prototype of getlogin_r
. It is zero if d_getlogin_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getlogin_r
is defined.
GETNETBYADDR_R_PROTO
This symbol encodes the prototype of getnetbyaddr_r
. It is zero if d_getnetbyaddr_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getnetbyaddr_r
is defined.
GETNETBYNAME_R_PROTO
This symbol encodes the prototype of getnetbyname_r
. It is zero if d_getnetbyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getnetbyname_r
is defined.
GETNETENT_R_PROTO
This symbol encodes the prototype of getnetent_r
. It is zero if d_getnetent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getnetent_r
is defined.
GETPROTOBYNAME_R_PROTO
This symbol encodes the prototype of getprotobyname_r
. It is zero if d_getprotobyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getprotobyname_r
is defined.
GETPROTOBYNUMBER_R_PROTO
This symbol encodes the prototype of getprotobynumber_r
. It is zero if d_getprotobynumber_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getprotobynumber_r
is defined.
GETPROTOENT_R_PROTO
This symbol encodes the prototype of getprotoent_r
. It is zero if d_getprotoent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getprotoent_r
is defined.
GETPWENT_R_PROTO
This symbol encodes the prototype of getpwent_r
. It is zero if d_getpwent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getpwent_r
is defined.
GETPWNAM_R_PROTO
This symbol encodes the prototype of getpwnam_r
. It is zero if d_getpwnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getpwnam_r
is defined.
GETPWUID_R_PROTO
This symbol encodes the prototype of getpwuid_r
. It is zero if d_getpwuid_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getpwuid_r
is defined.
GETSERVBYNAME_R_PROTO
This symbol encodes the prototype of getservbyname_r
. It is zero if d_getservbyname_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getservbyname_r
is defined.
GETSERVBYPORT_R_PROTO
This symbol encodes the prototype of getservbyport_r
. It is zero if d_getservbyport_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getservbyport_r
is defined.
GETSERVENT_R_PROTO
This symbol encodes the prototype of getservent_r
. It is zero if d_getservent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getservent_r
is defined.
GETSPNAM_R_PROTO
This symbol encodes the prototype of getspnam_r
. It is zero if d_getspnam_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_getspnam_r
is defined.
HAS_DBMINIT_PROTO
This symbol, if defined, indicates that the system provides a prototype for the dbminit()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int dbminit(char *);
HAS_DRAND48_PROTO
This symbol, if defined, indicates that the system provides a prototype for the drand48()
function. Otherwise, it is up to the program to supply one. A good guess is
extern double drand48(void);
HAS_FLOCK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the flock()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int flock(int, int);
HAS_GETHOST_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for gethostent()
, gethostbyname()
, and gethostbyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_GETNET_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for getnetent()
, getnetbyname()
, and getnetbyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_GETPROTO_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for getprotoent()
, getprotobyname()
, and getprotobyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_GETSERV_PROTOS
This symbol, if defined, indicates that netdb.h includes prototypes for getservent()
, getservbyname()
, and getservbyaddr()
. Otherwise, it is up to the program to guess them. See netdbtype.U (part of metaconfig) for probing for various Netdb_xxx_t
types.
HAS_MODFL_PROTO
This symbol, if defined, indicates that the system provides a prototype for the modfl()
function. Otherwise, it is up to the program to supply one.
HAS_SBRK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the sbrk()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern void* sbrk(int); extern void* sbrk(size_t);
HAS_SETRESGID_PROTO
This symbol, if defined, indicates that the system provides a prototype for the setresgid()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern int setresgid(uid_t ruid, uid_t euid, uid_t suid);
HAS_SETRESUID_PROTO
This symbol, if defined, indicates that the system provides a prototype for the setresuid()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern int setresuid(uid_t ruid, uid_t euid, uid_t suid);
HAS_SHMAT_PROTOTYPE
This symbol, if defined, indicates that the sys/shm.h includes a prototype for shmat()
. Otherwise, it is up to the program to guess one. Shmat_t
shmat(int, Shmat_t, int)
is a good guess, but not always right so it should be emitted by the program only when HAS_SHMAT_PROTOTYPE
is not defined to avoid conflicting defs.
HAS_SOCKATMARK_PROTO
This symbol, if defined, indicates that the system provides a prototype for the sockatmark()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int sockatmark(int);
HAS_SYSCALL_PROTO
This symbol, if defined, indicates that the system provides a prototype for the syscall()
function. Otherwise, it is up to the program to supply one. Good guesses are
extern int syscall(int, ...); extern int syscall(long, ...);
HAS_TELLDIR_PROTO
This symbol, if defined, indicates that the system provides a prototype for the telldir()
function. Otherwise, it is up to the program to supply one. A good guess is
extern long telldir(DIR*);
NDBM_H_USES_PROTOTYPES
This symbol, if defined, indicates that ndbm.h uses real ANSI
C prototypes instead of K&R style function declarations without any parameter information. While ANSI
C prototypes are supported in C++, K&R style function declarations will yield errors.
RANDOM_R_PROTO
This symbol encodes the prototype of random_r
. It is zero if d_random_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_random_r
is defined.
READDIR_R_PROTO
This symbol encodes the prototype of readdir_r
. It is zero if d_readdir_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_readdir_r
is defined.
SETGRENT_R_PROTO
This symbol encodes the prototype of setgrent_r
. It is zero if d_setgrent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setgrent_r
is defined.
SETHOSTENT_R_PROTO
This symbol encodes the prototype of sethostent_r
. It is zero if d_sethostent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_sethostent_r
is defined.
SETLOCALE_R_PROTO
This symbol encodes the prototype of setlocale_r
. It is zero if d_setlocale_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setlocale_r
is defined.
SETNETENT_R_PROTO
This symbol encodes the prototype of setnetent_r
. It is zero if d_setnetent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setnetent_r
is defined.
SETPROTOENT_R_PROTO
This symbol encodes the prototype of setprotoent_r
. It is zero if d_setprotoent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setprotoent_r
is defined.
SETPWENT_R_PROTO
This symbol encodes the prototype of setpwent_r
. It is zero if d_setpwent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setpwent_r
is defined.
SETSERVENT_R_PROTO
This symbol encodes the prototype of setservent_r
. It is zero if d_setservent_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_setservent_r
is defined.
SRAND48_R_PROTO
This symbol encodes the prototype of srand48_r
. It is zero if d_srand48_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_srand48_r
is defined.
SRANDOM_R_PROTO
This symbol encodes the prototype of srandom_r
. It is zero if d_srandom_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_srandom_r
is defined.
STRERROR_R_PROTO
This symbol encodes the prototype of strerror_r
. It is zero if d_strerror_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_strerror_r
is defined.
pregcomp
Described in perlreguts.
REGEXP* pregcomp(SV * const pattern, const U32 flags)
pregexec
Described in perlreguts.
I32 pregexec(REGEXP * const prog, char* stringarg, char* strend, char* strbeg, SSize_t minend, SV* screamer, U32 nosave)
re_compile
Compile the regular expression pattern pattern
, returning a pointer to the compiled object for later matching with the internal regex engine.
This function is typically used by a custom regexp engine .comp()
function to hand off to the core regexp engine those patterns it doesn't want to handle itself (typically passing through the same flags it was called with). In almost all other cases, a regexp should be compiled by calling "pregcomp
" to compile using the currently active regexp engine.
If pattern
is already a REGEXP
, this function does nothing but return a pointer to the input. Otherwise the PV is extracted and treated like a string representing a pattern. See perlre.
The possible flags for rx_flags
are documented in perlreapi. Their names all begin with RXf_
.
REGEXP* re_compile(SV * const pattern, U32 orig_rx_flags)
re_dup_guts
Duplicate a regexp.
This routine is expected to clone a given regexp structure. It is only compiled under USE_ITHREADS.
After all of the core data stored in struct regexp is duplicated the regexp_engine.dupe
method is used to copy any private data stored in the *pprivate pointer. This allows extensions to handle any duplication they need to do.
void re_dup_guts(const REGEXP *sstr, REGEXP *dstr, CLONE_PARAMS* param)
REGEX_LOCALE_CHARSET
Described in perlreapi.
REGEXP
Described in perlreapi.
regexp_engine
When a regexp is compiled, its engine
field is then set to point at the appropriate structure, so that when it needs to be used Perl can find the right routines to do so.
In order to install a new regexp handler, $^H{regcomp}
is set to an integer which (when casted appropriately) resolves to one of these structures. When compiling, the comp
method is executed, and the resulting regexp
structure's engine field is expected to point back at the same structure.
The pTHX_ symbol in the definition is a macro used by Perl under threading to provide an extra argument to the routine holding a pointer back to the interpreter that is executing the regexp. So under threading all routines get an extra argument.
regexp_paren_pair
Described in perlreapi.
regmatch_info
Some basic information about the current match that is created by Perl_regexec_flags and then passed to regtry(), regmatch() etc. It is allocated as a local var on the stack, so nothing should be stored in it that needs preserving or clearing up on croak(). For that, see the aux_info and aux_info_eval members of the regmatch_state union.
REXEC_COPY_STR
REXEC_COPY_SKIP_PRE
REXEC_COPY_SKIP_POST
Described in perlreapi.
RXapif_CLEAR
RXapif_DELETE
RXapif_EXISTS
RXapif_FETCH
RXapif_FIRSTKEY
RXapif_NEXTKEY
RXapif_SCALAR
RXapif_STORE
RXapif_ALL
RXapif_ONE
RXapif_REGNAME
RXapif_REGNAMES
RXapif_REGNAMES_COUNT
Described in perlreapi.
RX_BUFF_IDX_CARET_FULLMATCH
RX_BUFF_IDX_CARET_POSTMATCH
RX_BUFF_IDX_CARET_PREMATCH
RX_BUFF_IDX_FULLMATCH
RX_BUFF_IDX_POSTMATCH
RX_BUFF_IDX_PREMATCH
Described in perlreapi.
RXf_PMf_MULTILINE
RXf_PMf_SINGLELINE
RXf_PMf_FOLD
RXf_PMf_EXTENDED
RXf_PMf_KEEPCOPY
Described in perlreapi.
RXf_SPLIT
RXf_SKIPWHITE
RXf_START_ONLY
RXf_WHITE
RXf_NULL
RXf_NO_INPLACE_SUBST
Described in perlreapi.
RX_MATCH_COPIED
Described in perlreapi.
RX_MATCH_COPIED(const REGEXP * rx)
RX_OFFS
Described in perlreapi.
RX_OFFS(const REGEXP * rx_sv)
SvRX
Convenience macro to get the REGEXP from a SV. This is approximately equivalent to the following snippet:
if (SvMAGICAL(sv)) mg_get(sv); if (SvROK(sv)) sv = MUTABLE_SV(SvRV(sv)); if (SvTYPE(sv) == SVt_REGEXP) return (REGEXP*) sv;
NULL
will be returned if a REGEXP* is not found.
REGEXP * SvRX(SV *sv)
SvRXOK
Returns a boolean indicating whether the SV (or the one it references) is a REGEXP.
If you want to do something with the REGEXP* later use SvRX instead and check for NULL.
bool SvRXOK(SV* sv)
SV_SAVED_COPY
Described in perlreapi.
These are used in the simple report generation feature of Perl. See perlform.
IoBOTTOM_GV
Described in perlguts.
GV * IoBOTTOM_GV(IO *io)
IoBOTTOM_NAME
Described in perlguts.
char * IoBOTTOM_NAME(IO *io)
IoFMT_GV
Described in perlguts.
GV * IoFMT_GV(IO *io)
IoFMT_NAME
Described in perlguts.
char * IoFMT_NAME(IO *io)
IoLINES
Described in perlguts.
IV IoLINES(IO *io)
IoLINES_LEFT
Described in perlguts.
IV IoLINES_LEFT(IO *io)
IoPAGE
Described in perlguts.
IV IoPAGE(IO *io)
IoPAGE_LEN
Described in perlguts.
IV IoPAGE_LEN(IO *io)
IoTOP_GV
Described in perlguts.
GV * IoTOP_GV(IO *io)
IoTOP_NAME
Described in perlguts.
char * IoTOP_NAME(IO *io)
PERL_SIGNALS_UNSAFE_FLAG
If this bit in PL_signals
is set, the system is uing the pre-Perl 5.8 unsafe signals. See "PERL_SIGNALS" in perlrun and "Deferred Signals (Safe Signals)" in perlipc.
U32 PERL_SIGNALS_UNSAFE_FLAG
rsignal
A wrapper for the C library functions sigaction(2) or signal(2). Use this instead of those libc functions, as the Perl version gives the safest available implementation, and knows things that interact with the rest of the perl interpreter.
Sighandler_t rsignal(int i, Sighandler_t t)
rsignal_state
Returns a the current signal handler for signal signo
. See "rsignal
".
Sighandler_t rsignal_state(int i)
Siglongjmp
This macro is used in the same way as siglongjmp()
, but will invoke traditional longjmp()
if siglongjmp isn't available. See "HAS_SIGSETJMP"
.
void Siglongjmp(jmp_buf env, int val)
SIG_NAME
This symbol contains a list of signal names in order of signal number. This is intended to be used as a static array initialization, like this:
char *sig_name[] = { SIG_NAME };
The signals in the list are separated with commas, and each signal is surrounded by double quotes. There is no leading SIG
in the signal name, i.e. SIGQUIT
is known as "QUIT
". Gaps in the signal numbers (up to NSIG
) are filled in with NUMnn
, etc., where nn is the actual signal number (e.g. NUM37
). The signal number for sig_name[i]
is stored in sig_num[i]
. The last element is 0 to terminate the list with a NULL
. This corresponds to the 0 at the end of the sig_name_init
list. Note that this variable is initialized from the sig_name_init
, not from sig_name
(which is unused).
SIG_NUM
This symbol contains a list of signal numbers, in the same order as the SIG_NAME
list. It is suitable for static array initialization, as in:
int sig_num[] = { SIG_NUM };
The signals in the list are separated with commas, and the indices within that list and the SIG_NAME
list match, so it's easy to compute the signal name from a number or vice versa at the price of a small dynamic linear lookup. Duplicates are allowed, but are moved to the end of the list. The signal number corresponding to sig_name[i]
is sig_number[i]
. if (i < NSIG
) then sig_number[i]
== i. The last element is 0, corresponding to the 0 at the end of the sig_name_init
list. Note that this variable is initialized from the sig_num_init
, not from sig_num
(which is unused).
Sigsetjmp
This macro is used in the same way as sigsetjmp()
, but will invoke traditional setjmp()
if sigsetjmp isn't available. See "HAS_SIGSETJMP"
.
int Sigsetjmp(jmp_buf env, int savesigs)
SIG_SIZE
This variable contains the number of elements of the SIG_NAME
and SIG_NUM
arrays, excluding the final NULL
entry.
whichsig
whichsig_pv
whichsig_pvn
whichsig_sv
These all convert a signal name into its corresponding signal number; returning -1 if no corresponding number was found.
They differ only in the source of the signal name:
whichsig_pv
takes the name from the NUL
-terminated string starting at sig
.
whichsig
is merely a different spelling, a synonym, of whichsig_pv
.
whichsig_pvn
takes the name from the string starting at sig
, with length len
bytes.
whichsig_sv
takes the name from the PV stored in the SV sigsv
.
I32 whichsig (const char* sig) I32 whichsig_pv (const char* sig) I32 whichsig_pvn(const char* sig, STRLEN len) I32 whichsig_sv (SV* sigsv)
These variables give details as to where various libraries, installation destinations, etc., go, as well as what various installation options were selected
ARCHLIB
This variable, if defined, holds the name of the directory in which the user wants to put architecture-dependent public library files for perl5. It is most often a local directory such as /usr/local/lib. Programs using this variable must be prepared to deal with filename expansion. If ARCHLIB
is the same as PRIVLIB
, it is not defined, since presumably the program already searches PRIVLIB
.
ARCHLIB_EXP
This symbol contains the ~name expanded version of ARCHLIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
ARCHNAME
This symbol holds a string representing the architecture name. It may be used to construct an architecture-dependant pathname where library files may be held under a private library, for instance.
BIN
This symbol holds the path of the bin directory where the package will be installed. Program must be prepared to deal with ~name substitution.
BIN_EXP
This symbol is the filename expanded version of the BIN
symbol, for programs that do not want to deal with that at run-time.
INSTALL_USR_BIN_PERL
This symbol, if defined, indicates that Perl is to be installed also as /usr/bin/perl.
MULTIARCH
This symbol, if defined, signifies that the build process will produce some binary files that are going to be used in a cross-platform environment. This is the case for example with the NeXT "fat" binaries that contain executables for several CPUs
.
PERL_INC_VERSION_LIST
This variable specifies the list of subdirectories in over which perl.c:incpush()
and lib/lib.pm will automatically search when adding directories to @INC
, in a format suitable for a C initialization string. See the inc_version_list
entry in Porting/Glossary for more details.
PERL_OTHERLIBDIRS
This variable contains a colon-separated set of paths for the perl binary to search for additional library files or modules. These directories will be tacked to the end of @INC
. Perl will automatically search below each path for version- and architecture-specific directories. See "PERL_INC_VERSION_LIST"
for more details.
PERL_RELOCATABLE_INC
This symbol, if defined, indicates that we'd like to relocate entries in @INC
at run time based on the location of the perl binary.
PERL_TARGETARCH
This symbol, if defined, indicates the target architecture Perl has been cross-compiled to. Undefined if not a cross-compile.
PERL_USE_DEVEL
This symbol, if defined, indicates that Perl was configured with -Dusedevel
, to enable development features. This should not be done for production builds.
PERL_VENDORARCH
If defined, this symbol contains the name of a private library. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own architecture-dependent modules and extensions in this directory with
MakeMaker Makefile.PL INSTALLDIRS=vendor
or equivalent. See INSTALL
for details.
PERL_VENDORARCH_EXP
This symbol contains the ~name expanded version of PERL_VENDORARCH
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
PERL_VENDORLIB_EXP
This symbol contains the ~name expanded version of VENDORLIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
PERL_VENDORLIB_STEM
This define is PERL_VENDORLIB_EXP
with any trailing version-specific component removed. The elements in inc_version_list
(inc_version_list
.U (part of metaconfig)) can be tacked onto this variable to generate a list of directories to search.
PRIVLIB
This symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion.
PRIVLIB_EXP
This symbol contains the ~name expanded version of PRIVLIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITEARCH
This symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-dependent modules in this directory with
MakeMaker Makefile.PL
or equivalent. See INSTALL
for details.
SITEARCH_EXP
This symbol contains the ~name expanded version of SITEARCH
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITELIB
This symbol contains the name of the private library for this package. The library is private in the sense that it needn't be in anyone's execution path, but it should be accessible by the world. The program should be prepared to do ~ expansion. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-independent modules in this directory with
MakeMaker Makefile.PL
or equivalent. See INSTALL
for details.
SITELIB_EXP
This symbol contains the ~name expanded version of SITELIB
, to be used in programs that are not prepared to deal with ~ expansion at run-time.
SITELIB_STEM
This define is SITELIB_EXP
with any trailing version-specific component removed. The elements in inc_version_list
(inc_version_list
.U (part of metaconfig)) can be tacked onto this variable to generate a list of directories to search.
STARTPERL
This variable contains the string to put in front of a perl script to make sure (one hopes) that it runs with perl and not some shell.
USE_64_BIT_ALL
This symbol, if defined, indicates that 64-bit integers should be used when available. If not defined, the native integers will be used (be they 32 or 64 bits). The maximal possible 64-bitness is employed: LP64 or ILP64
, meaning that you will be able to use more than 2 gigabytes of memory. This mode is even more binary incompatible than USE_64_BIT_INT
. You may not be able to run the resulting executable in a 32-bit CPU
at all or you may need at least to reboot your OS to 64-bit mode.
USE_64_BIT_INT
This symbol, if defined, indicates that 64-bit integers should be used when available. If not defined, the native integers will be employed (be they 32 or 64 bits). The minimal possible 64-bitness is used, just enough to get 64-bit integers into Perl. This may mean using for example "long longs", while your memory may still be limited to 2 gigabytes.
USE_BSD_GETPGRP
This symbol, if defined, indicates that getpgrp needs one arguments whereas USG
one needs none.
USE_BSD_SETPGRP
This symbol, if defined, indicates that setpgrp needs two arguments whereas USG
one needs none. See also "HAS_SETPGID"
for a POSIX
interface.
USE_CPLUSPLUS
This symbol, if defined, indicates that a C++ compiler was used to compiled Perl and will be used to compile extensions.
USE_C_BACKTRACE
This symbol, if defined, indicates that Perl should be built with support for backtrace.
USE_DYNAMIC_LOADING
This symbol, if defined, indicates that dynamic loading of some sort is available.
USE_FAST_STDIO
This symbol, if defined, indicates that Perl should be built to use 'fast stdio'. Defaults to define in Perls 5.8 and earlier, to undef later.
USE_ITHREADS
This symbol, if defined, indicates that Perl should be built to use the interpreter-based threading implementation.
USE_KERN_PROC_PATHNAME
This symbol, if defined, indicates that we can use sysctl with KERN_PROC_PATHNAME
to get a full path for the executable, and hence convert $^X to an absolute path.
USE_LARGE_FILES
This symbol, if defined, indicates that large file support should be used when available.
USE_MORE_BITS
This symbol, if defined, indicates that 64-bit interfaces and long doubles should be used when available.
USE_NSGETEXECUTABLEPATH
This symbol, if defined, indicates that we can use _NSGetExecutablePath
and realpath to get a full path for the executable, and hence convert $^X to an absolute path.
USE_PERLIO
This symbol, if defined, indicates that the PerlIO abstraction should be used throughout. If not defined, stdio should be used in a fully backward compatible manner.
USE_QUADMATH
This symbol, if defined, indicates that the quadmath library should be used when available.
USE_REENTRANT_API
This symbol, if defined, indicates that Perl should try to use the various _r
versions of library functions. This is extremely experimental.
USE_SEMCTL_SEMID_DS
This symbol, if defined, indicates that struct semid_ds
* is used for semctl IPC_STAT
.
USE_STAT_BLOCKS
This symbol is defined if this system has a stat structure declaring st_blksize
and st_blocks
.
USE_STDIO_BASE
This symbol is defined if the _base
field (or similar) of the stdio FILE
structure can be used to access the stdio buffer for a file handle. If this is defined, then the FILE_base(fp)
macro will also be defined and should be used to access this field. Also, the FILE_bufsiz(fp)
macro will be defined and should be used to determine the number of bytes in the buffer. USE_STDIO_BASE
will never be defined unless USE_STDIO_PTR
is.
USE_STDIO_PTR
This symbol is defined if the _ptr
and _cnt
fields (or similar) of the stdio FILE
structure can be used to access the stdio buffer for a file handle. If this is defined, then the FILE_ptr(fp)
and FILE_cnt(fp)
macros will also be defined and should be used to access these fields.
HAS_SOCKADDR_SA_LEN
This symbol, if defined, indicates that the struct sockaddr
structure has a member called sa_len
, indicating the length of the structure.
HAS_SOCKADDR_STORAGE
This symbol, if defined, indicates the availability of struct sockaddr_storage
;
HAS_SOCKATMARK
This symbol, if defined, indicates that the sockatmark
routine is available to test whether a socket is at the out-of-band mark.
HAS_SOCKS5_INIT
This symbol, if defined, indicates that the socks5_init
routine is available to initialize SOCKS
5.
filter_add
Described in perlfilter.
SV* filter_add(filter_t funcp, SV* datasv)
filter_del
Delete most recently added instance of the filter function argument
void filter_del(filter_t funcp)
filter_read
Described in perlfilter.
I32 filter_read(int idx, SV *buf_sv, int maxlen)
scan_vstring
Returns a pointer to the next character after the parsed vstring, as well as updating the passed in sv.
Function must be called like
sv = sv_2mortal(newSV(5)); s = scan_vstring(s,e,sv);
where s and e are the start and end of the string. The sv should already be large enough to store the vstring passed in, for performance reasons.
This function may croak if fatal warnings are enabled in the calling scope, hence the sv_2mortal in the example (to prevent a leak). Make sure to do SvREFCNT_inc afterwards if you use sv_2mortal.
char* scan_vstring(const char *s, const char *const e, SV *sv)
dMARK
Declare a stack marker variable, mark
, for the XSUB. See "MARK"
and "dORIGMARK"
.
dMARK;
dORIGMARK
Saves the original stack mark for the XSUB. See "ORIGMARK"
.
dORIGMARK;
dSP
Declares a local copy of perl's stack pointer for the XSUB, available via the SP
macro. See "SP"
.
dSP;
EXTEND
Used to extend the argument stack for an XSUB's return values. Once used, guarantees that there is room for at least nitems
to be pushed onto the stack.
void EXTEND(SP, SSize_t nitems)
MARK
Stack marker variable for the XSUB. See "dMARK"
.
mPUSHi
Push an integer onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHi"
, "mXPUSHi"
and "XPUSHi"
.
void mPUSHi(IV iv)
mPUSHn
Push a double onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHn"
, "mXPUSHn"
and "XPUSHn"
.
void mPUSHn(NV nv)
mPUSHp
Push a string onto the stack. The stack must have room for this element. The len
indicates the length of the string. Does not use TARG
. See also "PUSHp"
, "mXPUSHp"
and "XPUSHp"
.
void mPUSHp(char* str, STRLEN len)
mPUSHs
Push an SV onto the stack and mortalizes the SV. The stack must have room for this element. Does not use TARG
. See also "PUSHs"
and "mXPUSHs"
.
void mPUSHs(SV* sv)
mPUSHu
Push an unsigned integer onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHu"
, "mXPUSHu"
and "XPUSHu"
.
void mPUSHu(UV uv)
mXPUSHi
Push an integer onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHi"
, "mPUSHi"
and "PUSHi"
.
void mXPUSHi(IV iv)
mXPUSHn
Push a double onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHn"
, "mPUSHn"
and "PUSHn"
.
void mXPUSHn(NV nv)
mXPUSHp
Push a string onto the stack, extending the stack if necessary. The len
indicates the length of the string. Does not use TARG
. See also "XPUSHp"
, mPUSHp
and PUSHp
.
void mXPUSHp(char* str, STRLEN len)
mXPUSHs
Push an SV onto the stack, extending the stack if necessary and mortalizes the SV. Does not use TARG
. See also "XPUSHs"
and "mPUSHs"
.
void mXPUSHs(SV* sv)
mXPUSHu
Push an unsigned integer onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHu"
, "mPUSHu"
and "PUSHu"
.
void mXPUSHu(UV uv)
ORIGMARK
The original stack mark for the XSUB. See "dORIGMARK"
.
PL_markstack
Described in perlguts.
PL_markstack_ptr
Described in perlguts.
PL_savestack
Described in perlguts.
PL_savestack_ix
Described in perlguts.
PL_scopestack
Described in perlguts.
PL_scopestack_ix
Described in perlguts.
PL_scopestack_name
Described in perlguts.
PL_stack_base
Described in perlguts.
PL_stack_sp
Described in perlguts.
PL_tmps_floor
Described in perlguts.
PL_tmps_ix
Described in perlguts.
PL_tmps_stack
Described in perlguts.
POPpbytex
Pops a string off the stack which must consist of bytes i.e. characters < 256.
char* POPpbytex
POPpx
Pops a string off the stack. Identical to POPp. There are two names for historical reasons.
char* POPpx
PUSHi
Push an integer onto the stack. The stack must have room for this element. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHi"
instead. See also "XPUSHi"
and "mXPUSHi"
.
void PUSHi(IV iv)
PUSHmortal
Push a new mortal SV onto the stack. The stack must have room for this element. Does not use TARG
. See also "PUSHs"
, "XPUSHmortal"
and "XPUSHs"
.
void PUSHmortal
PUSHn
Push a double onto the stack. The stack must have room for this element. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHn"
instead. See also "XPUSHn"
and "mXPUSHn"
.
void PUSHn(NV nv)
PUSHp
Push a string onto the stack. The stack must have room for this element. The len
indicates the length of the string. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHp"
instead. See also "XPUSHp"
and "mXPUSHp"
.
void PUSHp(char* str, STRLEN len)
PUSHs
Push an SV onto the stack. The stack must have room for this element. Does not handle 'set' magic. Does not use TARG
. See also "PUSHmortal"
, "XPUSHs"
, and "XPUSHmortal"
.
void PUSHs(SV* sv)
PUSHu
Push an unsigned integer onto the stack. The stack must have room for this element. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mPUSHu"
instead. See also "XPUSHu"
and "mXPUSHu"
.
void PUSHu(UV uv)
PUTBACK
Closing bracket for XSUB arguments. This is usually handled by xsubpp
. See "PUSHMARK"
and perlcall for other uses.
PUTBACK;
SAVEt_INT
Described in perlguts.
SP
Stack pointer. This is usually handled by xsubpp
. See "dSP"
and SPAGAIN
.
SPAGAIN
Refetch the stack pointer. Used after a callback. See perlcall.
SPAGAIN;
SSNEW
SSNEWa
SSNEWt
SSNEWat
These temporarily allocates data on the savestack, returning an I32 index into the savestack, because a pointer would get broken if the savestack is moved on reallocation. Use "SSPTR
" to convert the returned index into a pointer.
The forms differ in that plain SSNEW
allocates size
bytes; SSNEWt
and SSNEWat
allocate size
objects, each of which is type type
; and <SSNEWa> and SSNEWat
make sure to align the new data to an align
boundary. The most useful value for the alignment is likely to be "MEM_ALIGNBYTES
". The alignment will be preserved through savestack reallocation only if realloc returns data aligned to a size divisible by "align"!
I32 SSNEW (Size_t size) I32 SSNEWa (Size_t_size, Size_t align) I32 SSNEWt (Size_t size, type) I32 SSNEWat(Size_t_size, type, Size_t align)
SSPTR
SSPTRt
These convert the index
returned by L/<SSNEW
> and kin into actual pointers.
The difference is that SSPTR
casts the result to type
, and SSPTRt
casts it to a pointer of that type
.
type SSPTR (I32 index, type) type * SSPTRt(I32 index, type)
TARG
TARG
is short for "target". It is an entry in the pad that an OPs op_targ
refers to. It is scratchpad space, often used as a return value for the OP, but some use it for other purposes.
TARG;
TOPs
Described in perlguts.
XPUSHi
Push an integer onto the stack, extending the stack if necessary. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHi"
instead. See also "PUSHi"
and "mPUSHi"
.
void XPUSHi(IV iv)
XPUSHmortal
Push a new mortal SV onto the stack, extending the stack if necessary. Does not use TARG
. See also "XPUSHs"
, "PUSHmortal"
and "PUSHs"
.
void XPUSHmortal
XPUSHn
Push a double onto the stack, extending the stack if necessary. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHn"
instead. See also "PUSHn"
and "mPUSHn"
.
void XPUSHn(NV nv)
XPUSHp
Push a string onto the stack, extending the stack if necessary. The len
indicates the length of the string. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHp"
instead. See also "PUSHp"
and "mPUSHp"
.
void XPUSHp(char* str, STRLEN len)
XPUSHs
Push an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. Does not use TARG
. See also "XPUSHmortal"
, PUSHs
and PUSHmortal
.
void XPUSHs(SV* sv)
XPUSHu
Push an unsigned integer onto the stack, extending the stack if necessary. Handles 'set' magic. Uses TARG
, so dTARGET
or dXSTARG
should be called to declare it. Do not call multiple TARG
-oriented macros to return lists from XSUB's - see "mXPUSHu"
instead. See also "PUSHu"
and "mPUSHu"
.
void XPUSHu(UV uv)
XS_APIVERSION_BOOTCHECK
Macro to verify that the perl api version an XS module has been compiled against matches the api version of the perl interpreter it's being loaded into.
XS_APIVERSION_BOOTCHECK;
XSRETURN
Return from XSUB, indicating number of items on the stack. This is usually handled by xsubpp
.
void XSRETURN(int nitems)
XSRETURN_PV
Return a copy of a string from an XSUB immediately. Uses XST_mPV
.
void XSRETURN_PV(char* str)
XST_mIV
Place an integer into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mIV(int pos, IV iv)
XST_mNV
Place a double into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mNV(int pos, NV nv)
XST_mPV
Place a copy of a string into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mPV(int pos, char* str)
XST_mUNDEF
Place &PL_sv_undef
into the specified position pos
on the stack.
void XST_mUNDEF(int pos)
XST_mUV
Place an unsigned integer into the specified position pos
on the stack. The value is stored in a new mortal SV.
void XST_mUV(int pos, UV uv)
XS_VERSION
The version identifier for an XS module. This is usually handled automatically by ExtUtils::MakeMaker
. See "XS_VERSION_BOOTCHECK"
.
XS_VERSION_BOOTCHECK
Macro to verify that a PM module's $VERSION
variable matches the XS module's XS_VERSION
variable. This is usually handled automatically by xsubpp
. See "The VERSIONCHECK: Keyword" in perlxs.
XS_VERSION_BOOTCHECK;
See also "Unicode Support"
.
Copy
CopyD
The XSUB-writer's interface to the C memcpy
function. The src
is the source, dest
is the destination, nitems
is the number of items, and type
is the type. May fail on overlapping copies. See also "Move"
.
CopyD
is like Copy
but returns dest
. Useful for encouraging compilers to tail-call optimise.
void Copy (void* src, void* dest, int nitems, type) void * CopyD(void* src, void* dest, int nitems, type)
delimcpy
Copy a source buffer to a destination buffer, stopping at (but not including) the first occurrence in the source of an unescaped (defined below) delimiter byte, delim
. The source is the bytes between
. Similarly, the dest is from
and from_end
- 1to
up to to_end
.
The number of bytes copied is written to *retlen
.
Returns the position of the first uncopied delim
in the from
buffer, but if there is no such occurrence before from_end
, then from_end
is returned, and the entire buffer
is copied.from
.. from_end
- 1
If there is room in the destination available after the copy, an extra terminating safety NUL
byte is appended (not included in the returned length).
The error case is if the destination buffer is not large enough to accommodate everything that should be copied. In this situation, a value larger than
is written to to_end
- to
*retlen
, and as much of the source as fits will be written to the destination. Not having room for the safety NUL
is not considered an error.
In the following examples, let x
be the delimiter, and 0
represent a NUL
byte (NOT the digit 0
). Then we would have
Source Destination abcxdef abc0
provided the destination buffer is at least 4 bytes long.
An escaped delimiter is one which is immediately preceded by a single backslash. Escaped delimiters are copied, and the copy continues past the delimiter; the backslash is not copied:
Source Destination abc\xdef abcxdef0
(provided the destination buffer is at least 8 bytes long).
It's actually somewhat more complicated than that. A sequence of any odd number of backslashes escapes the following delimiter, and the copy continues with exactly one of the backslashes stripped.
Source Destination abc\xdef abcxdef0 abc\\\xdef abc\\xdef0 abc\\\\\xdef abc\\\\xdef0
(as always, if the destination is large enough)
An even number of preceding backslashes does not escape the delimiter, so that the copy stops just before it, and includes all the backslashes (no stripping; zero is considered even):
Source Destination abcxdef abc0 abc\\xdef abc\\0 abc\\\\xdef abc\\\\0
char* delimcpy(char* to, const char* to_end, const char* from, const char* from_end, const int delim, I32* retlen)
do_join
This performs a Perl join
, placing the joined output into sv
.
The elements to join are in SVs, stored in a C array of pointers to SVs, from **mark
to
. Hence **sp - 1
*mark
is a reference to the first SV. Each SV will be coerced into a PV if not one already.
delim
contains the string (or coerced into a string) that is to separate each of the joined elements.
If any component is in UTF-8, the result will be as well, and all non-UTF-8 components will be converted to UTF-8 as necessary.
Magic and tainting are handled.
void do_join(SV *sv, SV *delim, SV **mark, SV **sp)
do_sprintf
This performs a Perl sprintf
placing the string output into sv
.
The elements to format are in SVs, stored in a C array of pointers to SVs of length len
> and beginning at **sarg
. The element referenced by *sarg
is the format.
Magic and tainting are handled.
void do_sprintf(SV* sv, SSize_t len, SV** sarg)
fbm_compile
Analyzes the string in order to make fast searches on it using fbm_instr()
-- the Boyer-Moore algorithm.
void fbm_compile(SV* sv, U32 flags)
fbm_instr
Returns the location of the SV in the string delimited by big
and bigend
(bigend
) is the char following the last char). It returns NULL
if the string can't be found. The sv
does not have to be fbm_compiled
, but the search will not be as fast then.
char* fbm_instr(unsigned char* big, unsigned char* bigend, SV* littlestr, U32 flags)
foldEQ
Returns true if the leading len
bytes of the strings s1
and s2
are the same case-insensitively; false otherwise. Uppercase and lowercase ASCII range bytes match themselves and their opposite case counterparts. Non-cased and non-ASCII range bytes match only themselves.
I32 foldEQ(const char* a, const char* b, I32 len)
ibcmp_locale
This is a synonym for (! foldEQ_locale())
I32 ibcmp_locale(const char* a, const char* b, I32 len)
ibcmp_utf8
This is a synonym for (! foldEQ_utf8())
I32 ibcmp_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)
instr
Same as strstr(3), which finds and returns a pointer to the first occurrence of the NUL-terminated substring little
in the NUL-terminated string big
, returning NULL if not found. The terminating NUL bytes are not compared.
char* instr(const char* big, const char* little)
memCHRs
Returns the position of the first occurence of the byte c
in the literal string "list"
, or NULL if c
doesn't appear in "list"
. All bytes are treated as unsigned char. Thus this macro can be used to determine if c
is in a set of particular characters. Unlike strchr(3), it works even if c
is NUL
(and the set doesn't include NUL
).
bool memCHRs("list", char c)
memEQ
Test two buffers (which may contain embedded NUL
characters, to see if they are equal. The len
parameter indicates the number of bytes to compare. Returns true or false. It is undefined behavior if either of the buffers doesn't contain at least len
bytes.
bool memEQ(char* s1, char* s2, STRLEN len)
memEQs
Like "memEQ", but the second string is a literal enclosed in double quotes, l1
gives the number of bytes in s1
. Returns true or false.
bool memEQs(char* s1, STRLEN l1, "s2")
memNE
Test two buffers (which may contain embedded NUL
characters, to see if they are not equal. The len
parameter indicates the number of bytes to compare. Returns true or false. It is undefined behavior if either of the buffers doesn't contain at least len
bytes.
bool memNE(char* s1, char* s2, STRLEN len)
memNEs
Like "memNE", but the second string is a literal enclosed in double quotes, l1
gives the number of bytes in s1
. Returns true or false.
bool memNEs(char* s1, STRLEN l1, "s2")
Move
MoveD
The XSUB-writer's interface to the C memmove
function. The src
is the source, dest
is the destination, nitems
is the number of items, and type
is the type. Can do overlapping moves. See also "Copy"
.
MoveD
is like Move
but returns dest
. Useful for encouraging compilers to tail-call optimise.
void Move (void* src, void* dest, int nitems, type) void * MoveD(void* src, void* dest, int nitems, type)
my_snprintf
The C library snprintf
functionality, if available and standards-compliant (uses vsnprintf
, actually). However, if the vsnprintf
is not available, will unfortunately use the unsafe vsprintf
which can overrun the buffer (there is an overrun check, but that may be too late). Consider using sv_vcatpvf
instead, or getting vsnprintf
.
int my_snprintf(char *buffer, const Size_t len, const char *format, ...)
my_sprintf
DEPRECATED!
It is planned to remove my_sprintf
from a future release of Perl. Do not use it for new code; remove it from existing code.
Do NOT use this due to the possibility of overflowing buffer
. Instead use my_snprintf()
int my_sprintf(NN char *buffer, NN const char *pat, ...)
my_strlcat
The C library strlcat
if available, or a Perl implementation of it. This operates on C NUL
-terminated strings.
my_strlcat()
appends string src
to the end of dst
. It will append at most
characters. It will then size - strlen(dst) - 1
NUL
-terminate, unless size
is 0 or the original dst
string was longer than size
(in practice this should not happen as it means that either size
is incorrect or that dst
is not a proper NUL
-terminated string).
Note that size
is the full size of the destination buffer and the result is guaranteed to be NUL
-terminated if there is room. Note that room for the NUL
should be included in size
.
The return value is the total length that dst
would have if size
is sufficiently large. Thus it is the initial length of dst
plus the length of src
. If size
is smaller than the return, the excess was not appended.
Size_t my_strlcat(char *dst, const char *src, Size_t size)
my_strlcpy
The C library strlcpy
if available, or a Perl implementation of it. This operates on C NUL
-terminated strings.
my_strlcpy()
copies up to
characters from the string size - 1
src
to dst
, NUL
-terminating the result if size
is not 0.
The return value is the total length src
would be if the copy completely succeeded. If it is larger than size
, the excess was not copied.
Size_t my_strlcpy(char *dst, const char *src, Size_t size)
my_strnlen
The C library strnlen
if available, or a Perl implementation of it.
my_strnlen()
computes the length of the string, up to maxlen
characters. It will never attempt to address more than maxlen
characters, making it suitable for use with strings that are not guaranteed to be NUL-terminated.
Size_t my_strnlen(const char *str, Size_t maxlen)
my_vsnprintf
The C library vsnprintf
if available and standards-compliant. However, if the vsnprintf
is not available, will unfortunately use the unsafe vsprintf
which can overrun the buffer (there is an overrun check, but that may be too late). Consider using sv_vcatpvf
instead, or getting vsnprintf
.
int my_vsnprintf(char *buffer, const Size_t len, const char *format, va_list ap)
ninstr
Find the first (leftmost) occurrence of a sequence of bytes within another sequence. This is the Perl version of strstr()
, extended to handle arbitrary sequences, potentially containing embedded NUL
characters (NUL
is what the initial n
in the function name stands for; some systems have an equivalent, memmem()
, but with a somewhat different API).
Another way of thinking about this function is finding a needle in a haystack. big
points to the first byte in the haystack. big_end
points to one byte beyond the final byte in the haystack. little
points to the first byte in the needle. little_end
points to one byte beyond the final byte in the needle. All the parameters must be non-NULL
.
The function returns NULL
if there is no occurrence of little
within big
. If little
is the empty string, big
is returned.
Because this function operates at the byte level, and because of the inherent characteristics of UTF-8 (or UTF-EBCDIC), it will work properly if both the needle and the haystack are strings with the same UTF-8ness, but not if the UTF-8ness differs.
char* ninstr(const char* big, const char* bigend, const char* little, const char* lend)
PL_na
A scratch pad variable in which to store a STRLEN
value. If would have been better named something like PL_temp_strlen
.
It is is typically used with SvPV
when one is actually planning to discard the returned length, (hence the length is "Not Applicable", which is how this variable got its name).
It is usually more efficient to either declare a local variable and use that instead, or to use the SvPV_nolen
macro.
STRLEN PL_na
rninstr
Like "ninstr"
, but instead finds the final (rightmost) occurrence of a sequence of bytes within another sequence, returning NULL
if there is no such occurrence.
char* rninstr(const char* big, const char* bigend, const char* little, const char* lend)
savepv
Perl's version of strdup()
. Returns a pointer to a newly allocated string which is a duplicate of pv
. The size of the string is determined by strlen()
, which means it may not contain embedded NUL
characters and must have a trailing NUL
. To prevent memory leaks, the memory allocated for the new string needs to be freed when no longer needed. This can be done with the "Safefree"
function, or SAVEFREEPV
.
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as "savesharedpv"
.
char* savepv(const char* pv)
savepvn
Perl's version of what strndup()
would be if it existed. Returns a pointer to a newly allocated string which is a duplicate of the first len
bytes from pv
, plus a trailing NUL
byte. The memory allocated for the new string can be freed with the Safefree()
function.
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as "savesharedpvn"
.
char* savepvn(const char* pv, Size_t len)
savepvs
Like savepvn
, but takes a literal string instead of a string/length pair.
char* savepvs("literal string")
savesharedpv
A version of savepv()
which allocates the duplicate string in memory which is shared between threads.
char* savesharedpv(const char* pv)
savesharedpvn
A version of savepvn()
which allocates the duplicate string in memory which is shared between threads. (With the specific difference that a NULL
pointer is not acceptable)
char* savesharedpvn(const char *const pv, const STRLEN len)
savesharedpvs
A version of savepvs()
which allocates the duplicate string in memory which is shared between threads.
char* savesharedpvs("literal string")
savesharedsvpv
A version of savesharedpv()
which allocates the duplicate string in memory which is shared between threads.
char* savesharedsvpv(SV *sv)
savesvpv
A version of savepv()
/savepvn()
which gets the string to duplicate from the passed in SV using SvPV()
On some platforms, Windows for example, all allocated memory owned by a thread is deallocated when that thread ends. So if you need that not to happen, you need to use the shared memory functions, such as "savesharedsvpv"
.
char* savesvpv(SV* sv)
strEQ
Test two NUL
-terminated strings to see if they are equal. Returns true or false.
bool strEQ(char* s1, char* s2)
strGE
Test two NUL
-terminated strings to see if the first, s1
, is greater than or equal to the second, s2
. Returns true or false.
bool strGE(char* s1, char* s2)
strGT
Test two NUL
-terminated strings to see if the first, s1
, is greater than the second, s2
. Returns true or false.
bool strGT(char* s1, char* s2)
strLE
Test two NUL
-terminated strings to see if the first, s1
, is less than or equal to the second, s2
. Returns true or false.
bool strLE(char* s1, char* s2)
STRLEN
Described in perlguts.
strLT
Test two NUL
-terminated strings to see if the first, s1
, is less than the second, s2
. Returns true or false.
bool strLT(char* s1, char* s2)
strNE
Test two NUL
-terminated strings to see if they are different. Returns true or false.
bool strNE(char* s1, char* s2)
strnEQ
Test two NUL
-terminated strings to see if they are equal. The len
parameter indicates the number of bytes to compare. Returns true or false. (A wrapper for strncmp
).
bool strnEQ(char* s1, char* s2, STRLEN len)
strnNE
Test two NUL
-terminated strings to see if they are different. The len
parameter indicates the number of bytes to compare. Returns true or false. (A wrapper for strncmp
).
bool strnNE(char* s1, char* s2, STRLEN len)
STR_WITH_LEN
Returns two comma separated tokens of the input literal string, and its length. This is convenience macro which helps out in some API calls. Note that it can't be used as an argument to macros or functions that under some configurations might be macros, which means that it requires the full Perl_xxx(aTHX_ ...) form for any API calls where it's used.
pair STR_WITH_LEN("literal string")
Zero
ZeroD
The XSUB-writer's interface to the C memzero
function. The dest
is the destination, nitems
is the number of items, and type
is the type.
ZeroD
is like Zero
but returns dest
. Useful for encouraging compilers to tail-call optimise.
void Zero (void* dest, int nitems, type) void * ZeroD(void* dest, int nitems, type)
SVt_IV
Type flag for scalars. See "svtype".
SVt_NULL
Type flag for scalars. See "svtype".
SVt_NV
Type flag for scalars. See "svtype".
SVt_PV
Type flag for scalars. See "svtype".
SVt_PVAV
Type flag for arrays. See "svtype".
SVt_PVCV
Type flag for subroutines. See "svtype".
SVt_PVFM
Type flag for formats. See "svtype".
SVt_PVGV
Type flag for typeglobs. See "svtype".
SVt_PVHV
Type flag for hashes. See "svtype".
SVt_PVIO
Type flag for I/O objects. See "svtype".
SVt_PVIV
Type flag for scalars. See "svtype".
SVt_PVLV
Type flag for scalars. See "svtype".
SVt_PVMG
Type flag for scalars. See "svtype".
SVt_PVNV
Type flag for scalars. See "svtype".
SVt_REGEXP
Type flag for regular expressions. See "svtype".
svtype
An enum of flags for Perl types. These are found in the file sv.h in the svtype
enum. Test these flags with the SvTYPE
macro.
The types are:
SVt_NULL SVt_IV SVt_NV SVt_RV SVt_PV SVt_PVIV SVt_PVNV SVt_PVMG SVt_INVLIST SVt_REGEXP SVt_PVGV SVt_PVLV SVt_PVAV SVt_PVHV SVt_PVCV SVt_PVFM SVt_PVIO
These are most easily explained from the bottom up.
SVt_PVIO
is for I/O objects, SVt_PVFM
for formats, SVt_PVCV
for subroutines, SVt_PVHV
for hashes and SVt_PVAV
for arrays.
All the others are scalar types, that is, things that can be bound to a $
variable. For these, the internal types are mostly orthogonal to types in the Perl language.
Hence, checking SvTYPE(sv) < SVt_PVAV
is the best way to see whether something is a scalar.
SVt_PVGV
represents a typeglob. If !SvFAKE(sv)
, then it is a real, incoercible typeglob. If SvFAKE(sv)
, then it is a scalar to which a typeglob has been assigned. Assigning to it again will stop it from being a typeglob. SVt_PVLV
represents a scalar that delegates to another scalar behind the scenes. It is used, e.g., for the return value of substr
and for tied hash and array elements. It can hold any scalar value, including a typeglob. SVt_REGEXP
is for regular expressions. SVt_INVLIST
is for Perl core internal use only.
SVt_PVMG
represents a "normal" scalar (not a typeglob, regular expression, or delegate). Since most scalars do not need all the internal fields of a PVMG, we save memory by allocating smaller structs when possible. All the other types are just simpler forms of SVt_PVMG
, with fewer internal fields. SVt_NULL
can only hold undef. SVt_IV
can hold undef, an integer, or a reference. (SVt_RV
is an alias for SVt_IV
, which exists for backward compatibility.) SVt_NV
can hold any of those or a double. SVt_PV
can only hold undef
or a string. SVt_PVIV
is a superset of SVt_PV
and SVt_IV
. SVt_PVNV
is similar. SVt_PVMG
can hold anything SVt_PVNV
can hold, but it can, but does not have to, be blessed or magical.
boolSV
Returns a true SV if b
is a true value, or a false SV if b
is 0.
See also "PL_sv_yes"
and "PL_sv_no"
.
SV * boolSV(bool b)
croak_xs_usage
A specialised variant of croak()
for emitting the usage message for xsubs
croak_xs_usage(cv, "eee_yow");
works out the package name and subroutine name from cv
, and then calls croak()
. Hence if cv
is &ouch::awk
, it would call croak
as:
Perl_croak(aTHX_ "Usage: %" SVf "::%" SVf "(%s)", "ouch" "awk", "eee_yow");
void croak_xs_usage(const CV *const cv, const char *const params)
get_sv
Returns the SV of the specified Perl scalar. flags
are passed to "gv_fetchpv
". If GV_ADD
is set and the Perl variable does not exist then it will be created. If flags
is zero and the variable does not exist then NULL is returned.
NOTE: the perl_get_sv()
form is deprecated.
SV* get_sv(const char *name, I32 flags)
isGV_with_GP
Returns a boolean as to whether or not sv
is a GV with a pointer to a GP (glob pointer).
bool isGV_with_GP(SV * sv)
looks_like_number
Test if the content of an SV looks like a number (or is a number). Inf
and Infinity
are treated as numbers (so will not issue a non-numeric warning), even if your atof()
doesn't grok them. Get-magic is ignored.
I32 looks_like_number(SV *const sv)
MUTABLE_PTR
MUTABLE_AV
MUTABLE_CV
MUTABLE_GV
MUTABLE_HV
MUTABLE_IO
MUTABLE_SV
The MUTABLE_*
() macros cast pointers to the types shown, in such a way (compiler permitting) that casting away const-ness will give a warning; e.g.:
const SV *sv = ...; AV *av1 = (AV*)sv; <== BAD: the const has been silently cast away AV *av2 = MUTABLE_AV(sv); <== GOOD: it may warn
MUTABLE_PTR
is the base macro used to derive new casts. The other already-built-in ones return pointers to what their names indicate.
void * MUTABLE_PTR(void * p) AV * MUTABLE_AV (AV * p) CV * MUTABLE_CV (CV * p) GV * MUTABLE_GV (GV * p) HV * MUTABLE_HV (HV * p) IO * MUTABLE_IO (IO * p) SV * MUTABLE_SV (SV * p)
newRV
newRV_inc
These are identical. They create an RV wrapper for an SV. The reference count for the original SV is incremented.
SV* newRV(SV *const sv)
newRV_noinc
Creates an RV wrapper for an SV. The reference count for the original SV is not incremented.
SV* newRV_noinc(SV *const tmpRef)
newSV
Creates a new SV. A non-zero len
parameter indicates the number of bytes of preallocated string space the SV should have. An extra byte for a trailing NUL
is also reserved. (SvPOK
is not set for the SV even if string space is allocated.) The reference count for the new SV is set to 1.
In 5.9.3, newSV()
replaces the older NEWSV()
API, and drops the first parameter, x, a debug aid which allowed callers to identify themselves. This aid has been superseded by a new build option, PERL_MEM_LOG
(see "PERL_MEM_LOG" in perlhacktips). The older API is still there for use in XS modules supporting older perls.
SV* newSV(const STRLEN len)
newSVhek
Creates a new SV from the hash key structure. It will generate scalars that point to the shared string table where possible. Returns a new (undefined) SV if hek
is NULL.
SV* newSVhek(const HEK *const hek)
newSViv
Creates a new SV and copies an integer into it. The reference count for the SV is set to 1.
SV* newSViv(const IV i)
newSVnv
Creates a new SV and copies a floating point value into it. The reference count for the SV is set to 1.
SV* newSVnv(const NV n)
newSVpadname
NOTE: newSVpadname
is experimental and may change or be removed without notice.
Creates a new SV containing the pad name.
SV* newSVpadname(PADNAME *pn)
newSVpv
Creates a new SV and copies a string (which may contain NUL
(\0
) characters) into it. The reference count for the SV is set to 1. If len
is zero, Perl will compute the length using strlen()
, (which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte).
This function can cause reliability issues if you are likely to pass in empty strings that are not null terminated, because it will run strlen on the string and potentially run past valid memory.
Using "newSVpvn" is a safer alternative for non NUL
terminated strings. For string literals use "newSVpvs" instead. This function will work fine for NUL
terminated strings, but if you want to avoid the if statement on whether to call strlen
use newSVpvn
instead (calling strlen
yourself).
SV* newSVpv(const char *const s, const STRLEN len)
newSVpvf
Creates a new SV and initializes it with the string formatted like sv_catpvf
.
NOTE: newSVpvf
must be explicitly called as Perl_newSVpvf
with an aTHX_
parameter.
SV* Perl_newSVpvf(pTHX_ const char *const pat, ...)
newSVpvf_nocontext
Like "newSVpvf"
but does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
SV* newSVpvf_nocontext(const char *const pat, ...)
newSVpvn
Creates a new SV and copies a string into it, which may contain NUL
characters (\0
) and other binary data. The reference count for the SV is set to 1. Note that if len
is zero, Perl will create a zero length (Perl) string. You are responsible for ensuring that the source buffer is at least len
bytes long. If the buffer
argument is NULL the new SV will be undefined.
SV* newSVpvn(const char *const buffer, const STRLEN len)
newSVpvn_flags
Creates a new SV and copies a string (which may contain NUL
(\0
) characters) into it. The reference count for the SV is set to 1. Note that if len
is zero, Perl will create a zero length string. You are responsible for ensuring that the source string is at least len
bytes long. If the s
argument is NULL the new SV will be undefined. Currently the only flag bits accepted are SVf_UTF8
and SVs_TEMP
. If SVs_TEMP
is set, then sv_2mortal()
is called on the result before returning. If SVf_UTF8
is set, s
is considered to be in UTF-8 and the SVf_UTF8
flag will be set on the new SV. newSVpvn_utf8()
is a convenience wrapper for this function, defined as
#define newSVpvn_utf8(s, len, u) \ newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)
SV* newSVpvn_flags(const char *const s, const STRLEN len, const U32 flags)
newSVpvn_share
Creates a new SV with its SvPVX_const
pointing to a shared string in the string table. If the string does not already exist in the table, it is created first. Turns on the SvIsCOW
flag (or READONLY
and FAKE
in 5.16 and earlier). If the hash
parameter is non-zero, that value is used; otherwise the hash is computed. The string's hash can later be retrieved from the SV with the "SvSHARED_HASH"
macro. The idea here is that as the string table is used for shared hash keys these strings will have SvPVX_const == HeKEY
and hash lookup will avoid string compare.
SV* newSVpvn_share(const char* s, I32 len, U32 hash)
newSVpvn_utf8
Creates a new SV and copies a string (which may contain NUL
(\0
) characters) into it. If utf8
is true, calls SvUTF8_on
on the new SV. Implemented as a wrapper around newSVpvn_flags
.
SV* newSVpvn_utf8(const char* s, STRLEN len, U32 utf8)
newSVpvs
Like newSVpvn
, but takes a literal string instead of a string/length pair.
SV* newSVpvs("literal string")
newSVpvs_flags
Like newSVpvn_flags
, but takes a literal string instead of a string/length pair.
SV* newSVpvs_flags("literal string", U32 flags)
newSVpv_share
Like newSVpvn_share
, but takes a NUL
-terminated string instead of a string/length pair.
SV* newSVpv_share(const char* s, U32 hash)
newSVpvs_share
Like newSVpvn_share
, but takes a literal string instead of a string/length pair and omits the hash parameter.
SV* newSVpvs_share("literal string")
newSVrv
Creates a new SV for the existing RV, rv
, to point to. If rv
is not an RV then it will be upgraded to one. If classname
is non-null then the new SV will be blessed in the specified package. The new SV is returned and its reference count is 1. The reference count 1 is owned by rv
. See also newRV_inc() and newRV_noinc() for creating a new RV properly.
SV* newSVrv(SV *const rv, const char *const classname)
newSVsv
newSVsv_nomg
newSVsv_flags
These create a new SV which is an exact duplicate of the original SV (using sv_setsv
.)
They differ only in that newSVsv
performs 'get' magic; newSVsv_nomg
skips any magic; and newSVsv_flags
allows you to explicitly set a flags
parameter.
SV* newSVsv (SV *const old) SV* newSVsv_nomg (SV *const old) SV* newSVsv_flags(SV *const old, I32 flags)
newSV_type
Creates a new SV, of the type specified. The reference count for the new SV is set to 1.
SV* newSV_type(const svtype type)
newSV_type_mortal
Creates a new mortal SV, of the type specified. The reference count for the new SV is set to 1.
This is equivalent to SV* sv = sv_2mortal(newSV_type(<some type>)) and SV* sv = sv_newmortal(); sv_upgrade(sv, <some_type>) but should be more efficient than both of them. (Unless sv_2mortal is inlined at some point in the future.)
SV* newSV_type_mortal(const svtype type)
newSVuv
Creates a new SV and copies an unsigned integer into it. The reference count for the SV is set to 1.
SV* newSVuv(const UV u)
PL_sv_no
This is the false
SV. It is readonly. See "PL_sv_yes"
. Always refer to this as &PL_sv_no
.
SV PL_sv_no
PL_sv_undef
This is the undef
SV. It is readonly. Always refer to this as &PL_sv_undef
.
SV PL_sv_undef
PL_sv_yes
This is the true
SV. It is readonly. See "PL_sv_no"
. Always refer to this as &PL_sv_yes
.
SV PL_sv_yes
PL_sv_zero
This readonly SV has a zero numeric value and a "0"
string value. It's similar to "PL_sv_no"
except for its string value. Can be used as a cheap alternative to mXPUSHi(0)
for example. Always refer to this as &PL_sv_zero
. Introduced in 5.28.
SV PL_sv_zero
SAVE_DEFSV
Localize $_
. See "Localizing changes" in perlguts.
void SAVE_DEFSV
sortsv
In-place sort an array of SV pointers with the given comparison routine.
Currently this always uses mergesort. See "sortsv_flags"
for a more flexible routine.
void sortsv(SV** array, size_t num_elts, SVCOMPARE_t cmp)
sortsv_flags
In-place sort an array of SV pointers with the given comparison routine, with various SORTf_* flag options.
void sortsv_flags(SV** array, size_t num_elts, SVCOMPARE_t cmp, U32 flags)
SV
Described in perlguts.
sv_2cv
Using various gambits, try to get a CV from an SV; in addition, try if possible to set *st
and *gvp
to the stash and GV associated with it. The flags in lref
are passed to gv_fetchsv
.
CV* sv_2cv(SV* sv, HV **const st, GV **const gvp, const I32 lref)
sv_2io
Using various gambits, try to get an IO from an SV: the IO slot if its a GV; or the recursive result if we're an RV; or the IO slot of the symbol named after the PV if we're a string.
'Get' magic is ignored on the sv
passed in, but will be called on SvRV(sv)
if sv
is an RV.
IO* sv_2io(SV *const sv)
sv_2iv_flags
Return the integer value of an SV, doing any necessary string conversion. If flags
has the SV_GMAGIC
bit set, does an mg_get()
first. Normally used via the SvIV(sv)
and SvIVx(sv)
macros.
IV sv_2iv_flags(SV *const sv, const I32 flags)
sv_2mortal
Marks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call to FREETMPS
, or by an implicit call at places such as statement boundaries. SvTEMP()
is turned on which means that the SV's string buffer can be "stolen" if this SV is copied. See also "sv_newmortal"
and "sv_mortalcopy"
.
SV* sv_2mortal(SV *const sv)
sv_2nv_flags
Return the num value of an SV, doing any necessary string or integer conversion. If flags
has the SV_GMAGIC
bit set, does an mg_get()
first. Normally used via the SvNV(sv)
and SvNVx(sv)
macros.
NV sv_2nv_flags(SV *const sv, const I32 flags)
sv_2pv
sv_2pv_flags
These implement the various forms of the "SvPV
" in perlapi macros. The macros are the preferred interface.
These return a pointer to the string value of an SV (coercing it to a string if necessary), and set *lp
to its length in bytes.
The forms differ in that plain sv_2pvbyte
always processes 'get' magic; and sv_2pvbyte_flags
processes 'get' magic if and only if flags
contains SV_GMAGIC
.
char* sv_2pv (SV *sv, STRLEN *lp) char* sv_2pv_flags(SV *const sv, STRLEN *const lp, const U32 flags)
sv_2pvbyte
sv_2pvbyte_flags
These implement the various forms of the "SvPVbyte
" in perlapi macros. The macros are the preferred interface.
These return a pointer to the byte-encoded representation of the SV, and set *lp
to its length. If the SV is marked as being encoded as UTF-8, it will be downgraded, if possible, to a byte string. If the SV cannot be downgraded, they croak.
The forms differ in that plain sv_2pvbyte
always processes 'get' magic; and sv_2pvbyte_flags
processes 'get' magic if and only if flags
contains SV_GMAGIC
.
char* sv_2pvbyte (SV *sv, STRLEN *const lp) char* sv_2pvbyte_flags(SV *sv, STRLEN *const lp, const U32 flags)
sv_2pvutf8
sv_2pvutf8_flags
These implement the various forms of the "SvPVutf8
" in perlapi macros. The macros are the preferred interface.
These return a pointer to the UTF-8-encoded representation of the SV, and set *lp
to its length in bytes. They may cause the SV to be upgraded to UTF-8 as a side-effect.
The forms differ in that plain sv_2pvutf8
always processes 'get' magic; and sv_2pvutf8_flags
processes 'get' magic if and only if flags
contains SV_GMAGIC
.
char* sv_2pvutf8 (SV *sv, STRLEN *const lp) char* sv_2pvutf8_flags(SV *sv, STRLEN *const lp, const U32 flags)
sv_2uv_flags
Return the unsigned integer value of an SV, doing any necessary string conversion. If flags
has the SV_GMAGIC
bit set, does an mg_get()
first. Normally used via the SvUV(sv)
and SvUVx(sv)
macros.
UV sv_2uv_flags(SV *const sv, const I32 flags)
SvAMAGIC
Returns a boolean as to whether sv
has overloading (active magic) enabled or not.
bool SvAMAGIC(SV * sv)
sv_backoff
Remove any string offset. You should normally use the SvOOK_off
macro wrapper instead.
void sv_backoff(SV *const sv)
sv_bless
Blesses an SV into a specified package. The SV must be an RV. The package must be designated by its stash (see "gv_stashpv"
). The reference count of the SV is unaffected.
SV* sv_bless(SV *const sv, HV *const stash)
sv_catpv
sv_catpv_flags
sv_catpv_mg
sv_catpv_nomg
These concatenate the NUL
-terminated string sstr
onto the end of the string which is in the SV. If the SV has the UTF-8 status set, then the bytes appended should be valid UTF-8.
They differ only in how they handle magic:
sv_catpv_mg
performs both 'get' and 'set' magic.
sv_catpv
performs only 'get' magic.
sv_catpv_nomg
skips all magic.
sv_catpv_flags
has an extra flags
parameter which allows you to specify any combination of magic handling (using SV_GMAGIC
and/or SV_SMAGIC
), and to also override the UTF-8 handling. By supplying the SV_CATUTF8
flag, the appended string is forced to be interpreted as UTF-8; by supplying instead the SV_CATBYTES
flag, it will be interpreted as just bytes. Either the SV or the string appended will be upgraded to UTF-8 if necessary.
void sv_catpv (SV *const dsv, const char* sstr) void sv_catpv_flags(SV *dsv, const char *sstr, const I32 flags) void sv_catpv_mg (SV *const dsv, const char *const sstr) void sv_catpv_nomg (SV *const dsv, const char* sstr)
sv_catpvf
sv_catpvf_nocontext
sv_catpvf_mg
sv_catpvf_mg_nocontext
These process their arguments like sprintf
, and append the formatted output to an SV. As with sv_vcatpvfn
, argument reordering is not supporte when called with a non-null C-style variable argument list.
If the appended data contains "wide" characters (including, but not limited to, SVs with a UTF-8 PV formatted with %s
, and characters >255 formatted with %c
), the original SV might get upgraded to UTF-8.
If the original SV was UTF-8, the pattern should be valid UTF-8; if the original SV was bytes, the pattern should be too.
All perform 'get' magic, but only sv_catpvf_mg
and sv_catpvf_mg_nocontext
perform 'set' magic.
sv_catpvf_nocontext
and sv_catpvf_mg_nocontext
do not take a thread context (aTHX
) parameter, so are used in situations where the caller doesn't already have the thread context.
NOTE: sv_catpvf
must be explicitly called as Perl_sv_catpvf
with an aTHX_
parameter.
NOTE: sv_catpvf_mg
must be explicitly called as Perl_sv_catpvf_mg
with an aTHX_
parameter.
void Perl_sv_catpvf (pTHX_ SV *const sv, const char *const pat, ...) void sv_catpvf_nocontext (SV *const sv, const char *const pat, ...) void Perl_sv_catpvf_mg (pTHX_ SV *const sv, const char *const pat, ...) void sv_catpvf_mg_nocontext(SV *const sv, const char *const pat, ...)
sv_catpvn
sv_catpvn_flags
sv_catpvn_mg
sv_catpvn_nomg
These concatenate the len
bytes of the string beginning at ptr
onto the end of the string which is in dsv
. The caller must make sure ptr
contains at least len
bytes.
For all but sv_catpvn_flags
, the string appended is assumed to be valid UTF-8 if the SV has the UTF-8 status set, and a string of bytes otherwise.
They differ in that:
sv_catpvn_mg
performs both 'get' and 'set' magic on dsv
.
sv_catpvn
performs only 'get' magic.
sv_catpvn_nomg
skips all magic.
sv_catpvn_flags
has an extra flags
parameter which allows you to specify any combination of magic handling (using SV_GMAGIC
and/or SV_SMAGIC
) and to also override the UTF-8 handling. By supplying the SV_CATBYTES
flag, the appended string is interpreted as plain bytes; by supplying instead the SV_CATUTF8
flag, it will be interpreted as UTF-8, and the dsv
will be upgraded to UTF-8 if necessary.
sv_catpvn
, sv_catpvn_mg
, and sv_catpvn_nomg
are implemented in terms of sv_catpvn_flags
.
void sv_catpvn (SV *dsv, const char *sstr, STRLEN len) void sv_catpvn_flags(SV *const dsv, const char *sstr, const STRLEN len, const I32 flags) void sv_catpvn_mg (SV *dsv, const char *sstr, STRLEN len) void sv_catpvn_nomg (SV *dsv, const char *sstr, STRLEN len)
sv_catpvs
Like sv_catpvn
, but takes a literal string instead of a string/length pair.
void sv_catpvs(SV* sv, "literal string")
sv_catpvs_flags
Like sv_catpvn_flags
, but takes a literal string instead of a string/length pair.
void sv_catpvs_flags(SV* sv, "literal string", I32 flags)
sv_catpvs_mg
Like sv_catpvn_mg
, but takes a literal string instead of a string/length pair.
void sv_catpvs_mg(SV* sv, "literal string")
sv_catpvs_nomg
Like sv_catpvn_nomg
, but takes a literal string instead of a string/length pair.
void sv_catpvs_nomg(SV* sv, "literal string")
sv_catsv
sv_catsv_flags
sv_catsv_mg
sv_catsv_nomg
These concatenate the string from SV sstr
onto the end of the string in SV dsv
. If sstr
is null, these are no-ops; otherwise only dsv
is modified.
They differ only in what magic they perform:
sv_catsv_mg
performs 'get' magic on both SVs before the copy, and 'set' magic on dsv
afterwards.
sv_catsv
performs just 'get' magic, on both SVs.
sv_catsv_nomg
skips all magic.
sv_catsv_flags
has an extra flags
parameter which allows you to use SV_GMAGIC
and/or SV_SMAGIC
to specify any combination of magic handling (although either both or neither SV will have 'get' magic applied to it.)
sv_catsv
, sv_catsv_mg
, and sv_catsv_nomg
are implemented in terms of sv_catsv_flags
.
void sv_catsv (SV *dsv, SV *sstr) void sv_catsv_flags(SV *const dsv, SV *const sstr, const I32 flags) void sv_catsv_mg (SV *dsv, SV *sstr) void sv_catsv_nomg (SV *dsv, SV *sstr)
sv_chop
Efficient removal of characters from the beginning of the string buffer. SvPOK(sv)
, or at least SvPOKp(sv)
, must be true and ptr
must be a pointer to somewhere inside the string buffer. ptr
becomes the first character of the adjusted string. Uses the OOK
hack. On return, only SvPOK(sv)
and SvPOKp(sv)
among the OK
flags will be true.
Beware: after this function returns, ptr
and SvPVX_const(sv) may no longer refer to the same chunk of data.
The unfortunate similarity of this function's name to that of Perl's chop
operator is strictly coincidental. This function works from the left; chop
works from the right.
void sv_chop(SV *const sv, const char *const ptr)
sv_clear
Clear an SV: call any destructors, free up any memory used by the body, and free the body itself. The SV's head is not freed, although its type is set to all 1's so that it won't inadvertently be assumed to be live during global destruction etc. This function should only be called when REFCNT
is zero. Most of the time you'll want to call sv_free()
(or its macro wrapper SvREFCNT_dec
) instead.
void sv_clear(SV *const orig_sv)
sv_cmp
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in sv1
is less than, equal to, or greater than the string in sv2
. Is UTF-8 and
aware, handles get magic, and will coerce its args to strings if necessary. See also 'use bytes'
"sv_cmp_locale"
.
I32 sv_cmp(SV *const sv1, SV *const sv2)
sv_cmp_flags
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in sv1
is less than, equal to, or greater than the string in sv2
. Is UTF-8 and
aware and will coerce its args to strings if necessary. If the flags has the 'use bytes'
SV_GMAGIC
bit set, it handles get magic. See also "sv_cmp_locale_flags"
.
I32 sv_cmp_flags(SV *const sv1, SV *const sv2, const U32 flags)
sv_cmp_locale
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and
aware, handles get magic, and will coerce its args to strings if necessary. See also 'use bytes'
"sv_cmp"
.
I32 sv_cmp_locale(SV *const sv1, SV *const sv2)
sv_cmp_locale_flags
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and
aware and will coerce its args to strings if necessary. If the flags contain 'use bytes'
SV_GMAGIC
, it handles get magic. See also "sv_cmp_flags"
.
I32 sv_cmp_locale_flags(SV *const sv1, SV *const sv2, const U32 flags)
sv_collxfrm
This calls sv_collxfrm_flags
with the SV_GMAGIC flag. See "sv_collxfrm_flags"
.
char* sv_collxfrm(SV *const sv, STRLEN *const nxp)
sv_collxfrm_flags
Add Collate Transform magic to an SV if it doesn't already have it. If the flags contain SV_GMAGIC
, it handles get-magic.
Any scalar variable may carry PERL_MAGIC_collxfrm
magic that contains the scalar data of the variable, but transformed to such a format that a normal memory comparison can be used to compare the data according to the locale settings.
char* sv_collxfrm_flags(SV *const sv, STRLEN *const nxp, I32 const flags)
sv_copypv
sv_copypv_nomg
sv_copypv_flags
These copy a stringified representation of the source SV into the destination SV. They automatically perform coercion of numeric values into strings. Guaranteed to preserve the UTF8
flag even from overloaded objects. Similar in nature to sv_2pv[_flags]
but they operate directly on an SV instead of just the string. Mostly they use "sv_2pv_flags
" to do the work, except when that would lose the UTF-8'ness of the PV.
The three forms differ only in whether or not they perform 'get magic' on sv
. sv_copypv_nomg
skips 'get magic'; sv_copypv
performs it; and sv_copypv_flags
either performs it (if the SV_GMAGIC
bit is set in flags
) or doesn't (if that bit is cleared).
void sv_copypv (SV *const dsv, SV *const ssv) void sv_copypv_nomg (SV *const dsv, SV *const ssv) void sv_copypv_flags(SV *const dsv, SV *const ssv, const I32 flags)
SvCUR
Returns the length, in bytes, of the PV inside the SV. Note that this may not match Perl's length
; for that, use sv_len_utf8(sv)
. See "SvLEN"
also.
STRLEN SvCUR(SV* sv)
SvCUR_set
Sets the current length, in bytes, of the C string which is in the SV. See "SvCUR"
and SvIV_set
>.
void SvCUR_set(SV* sv, STRLEN len)
sv_dec
sv_dec_nomg
These auto-decrement the value in the SV, doing string to numeric conversion if necessary. They both handle operator overloading.
They differ only in that:
sv_dec
handles 'get' magic; sv_dec_nomg
skips 'get' magic.
void sv_dec(SV *const sv)
sv_derived_from
Exactly like "sv_derived_from_pv", but doesn't take a flags
parameter.
bool sv_derived_from(SV* sv, const char *const name)
sv_derived_from_pv
Exactly like "sv_derived_from_pvn", but takes a nul-terminated string instead of a string/length pair.
bool sv_derived_from_pv(SV* sv, const char *const name, U32 flags)
sv_derived_from_pvn
Returns a boolean indicating whether the SV is derived from the specified class at the C level. To check derivation at the Perl level, call isa()
as a normal Perl method.
Currently, the only significant value for flags
is SVf_UTF8.
bool sv_derived_from_pvn(SV* sv, const char *const name, const STRLEN len, U32 flags)
sv_derived_from_sv
Exactly like "sv_derived_from_pvn", but takes the name string in the form of an SV instead of a string/length pair. This is the advised form.
bool sv_derived_from_sv(SV* sv, SV *namesv, U32 flags)
sv_does
Like "sv_does_pv", but doesn't take a flags
parameter.
bool sv_does(SV* sv, const char *const name)
sv_does_pv
Like "sv_does_sv", but takes a nul-terminated string instead of an SV.
bool sv_does_pv(SV* sv, const char *const name, U32 flags)
sv_does_pvn
Like "sv_does_sv", but takes a string/length pair instead of an SV.
bool sv_does_pvn(SV* sv, const char *const name, const STRLEN len, U32 flags)
sv_does_sv
Returns a boolean indicating whether the SV performs a specific, named role. The SV can be a Perl object or the name of a Perl class.
bool sv_does_sv(SV* sv, SV* namesv, U32 flags)
SvEND
Returns a pointer to the spot just after the last character in the string which is in the SV, where there is usually a trailing NUL
character (even though Perl scalars do not strictly require it). See "SvCUR"
. Access the character as *(SvEND(sv))
.
Warning: If SvCUR
is equal to SvLEN
, then SvEND
points to unallocated memory.
char* SvEND(SV* sv)
sv_eq
Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF-8 and
aware, handles get magic, and will coerce its args to strings if necessary.'use bytes'
This function does not handle operator overloading. For a version that does, see instead sv_streq
.
I32 sv_eq(SV* sv1, SV* sv2)
sv_eq_flags
Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF-8 and
aware and coerces its args to strings if necessary. If the flags has the 'use bytes'
SV_GMAGIC
bit set, it handles get-magic, too.
This function does not handle operator overloading. For a version that does, see instead sv_streq_flags
.
I32 sv_eq_flags(SV* sv1, SV* sv2, const U32 flags)
sv_force_normal
Undo various types of fakery on an SV: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to an xpvmg
. See also "sv_force_normal_flags"
.
void sv_force_normal(SV *sv)
sv_force_normal_flags
Undo various types of fakery on an SV, where fakery means "more than" a string: if the PV is a shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to an xpvmg
; if we're a copy-on-write scalar, this is the on-write time when we do the copy, and is also used locally; if this is a vstring, drop the vstring magic. If SV_COW_DROP_PV
is set then a copy-on-write scalar drops its PV buffer (if any) and becomes SvPOK_off
rather than making a copy. (Used where this scalar is about to be set to some other value.) In addition, the flags
parameter gets passed to sv_unref_flags()
when unreffing. sv_force_normal
calls this function with flags set to 0.
This function is expected to be used to signal to perl that this SV is about to be written to, and any extra book-keeping needs to be taken care of. Hence, it croaks on read-only values.
void sv_force_normal_flags(SV *const sv, const U32 flags)
sv_free
Decrement an SV's reference count, and if it drops to zero, call sv_clear
to invoke destructors and free up any memory used by the body; finally, deallocating the SV's head itself. Normally called via a wrapper macro SvREFCNT_dec
.
void sv_free(SV *const sv)
SvGAMAGIC
Returns true if the SV has get magic or overloading. If either is true then the scalar is active data, and has the potential to return a new value every time it is accessed. Hence you must be careful to only read it once per user logical operation and work with that returned value. If neither is true then the scalar's value cannot change unless written to.
U32 SvGAMAGIC(SV* sv)
SvGETMAGIC
Invokes "mg_get"
on an SV if it has 'get' magic. For example, this will call FETCH
on a tied variable. This macro evaluates its argument more than once.
void SvGETMAGIC(SV* sv)
sv_gets
Get a line from the filehandle and store it into the SV, optionally appending to the currently-stored string. If append
is not 0, the line is appended to the SV instead of overwriting it. append
should be set to the byte offset that the appended string should start at in the SV (typically, SvCUR(sv)
is a suitable choice).
char* sv_gets(SV *const sv, PerlIO *const fp, I32 append)
sv_get_backrefs
NOTE: sv_get_backrefs
is experimental and may change or be removed without notice.
If sv
is the target of a weak reference then it returns the back references structure associated with the sv; otherwise return NULL
.
When returning a non-null result the type of the return is relevant. If it is an AV then the elements of the AV are the weak reference RVs which point at this item. If it is any other type then the item itself is the weak reference.
See also Perl_sv_add_backref()
, Perl_sv_del_backref()
, Perl_sv_kill_backrefs()
SV* sv_get_backrefs(SV *const sv)
SvGROW
Expands the character buffer in the SV so that it has room for the indicated number of bytes (remember to reserve space for an extra trailing NUL
character). Calls sv_grow
to perform the expansion if necessary. Returns a pointer to the character buffer. SV must be of type >= SVt_PV
. One alternative is to call sv_grow
if you are not sure of the type of SV.
You might mistakenly think that len
is the number of bytes to add to the existing size, but instead it is the total size sv
should be.
char * SvGROW(SV* sv, STRLEN len)
sv_inc
sv_inc_nomg
These auto-increment the value in the SV, doing string to numeric conversion if necessary. They both handle operator overloading.
They differ only in that sv_inc
performs 'get' magic; sv_inc_nomg
skips any magic.
void sv_inc(SV *const sv)
sv_insert
Inserts and/or replaces a string at the specified offset/length within the SV. Similar to the Perl substr()
function, with littlelen
bytes starting at little
replacing len
bytes of the string in bigstr
starting at offset
. Handles get magic.
void sv_insert(SV *const bigstr, const STRLEN offset, const STRLEN len, const char *const little, const STRLEN littlelen)
sv_insert_flags
Same as sv_insert
, but the extra flags
are passed to the SvPV_force_flags
that applies to bigstr
.
void sv_insert_flags(SV *const bigstr, const STRLEN offset, const STRLEN len, const char *little, const STRLEN littlelen, const U32 flags)
SvIOK_notUV
Returns a boolean indicating whether the SV contains a signed integer.
bool SvIOK_notUV(SV* sv)
SvIOK_only
Tells an SV that it is an integer and disables all other OK
bits.
void SvIOK_only(SV* sv)
SvIOK_only_UV
Tells an SV that it is an unsigned integer and disables all other OK
bits.
void SvIOK_only_UV(SV* sv)
SvIOKp
Returns a U32 value indicating whether the SV contains an integer. Checks the private setting. Use SvIOK
instead.
U32 SvIOKp(SV* sv)
SvIOK_UV
Returns a boolean indicating whether the SV contains an integer that must be interpreted as unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be flagged as either SvUOK
or SvIOK
.
bool SvIOK_UV(SV* sv)
sv_isa
Returns a boolean indicating whether the SV is blessed into the specified class.
This does not check for subtypes or method overloading. Use sv_isa_sv
to verify an inheritance relationship in the same way as the isa
operator by respecting any isa()
method overloading; or sv_derived_from_sv
to test directly on the actual object type.
int sv_isa(SV* sv, const char *const name)
sv_isa_sv
NOTE: sv_isa_sv
is experimental and may change or be removed without notice.
Returns a boolean indicating whether the SV is an object reference and is derived from the specified class, respecting any isa()
method overloading it may have. Returns false if sv
is not a reference to an object, or is not derived from the specified class.
This is the function used to implement the behaviour of the isa
operator.
Does not invoke magic on sv
.
Not to be confused with the older sv_isa
function, which does not use an overloaded isa()
method, nor will check subclassing.
bool sv_isa_sv(SV* sv, SV* namesv)
SvIsBOOL
Returns true if the SV is one of the special boolean constants (PL_sv_yes or PL_sv_no), or is a regular SV whose last assignment stored a copy of one.
bool SvIsBOOL(SV* sv)
SvIsCOW
Returns a U32 value indicating whether the SV is Copy-On-Write (either shared hash key scalars, or full Copy On Write scalars if 5.9.0 is configured for COW).
U32 SvIsCOW(SV* sv)
SvIsCOW_shared_hash
Returns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.
bool SvIsCOW_shared_hash(SV* sv)
sv_isobject
Returns a boolean indicating whether the SV is an RV pointing to a blessed object. If the SV is not an RV, or if the object is not blessed, then this will return false.
int sv_isobject(SV* sv)
SvIV
SvIVx
SvIV_nomg
These coerce the given SV to IV and return it. The returned value in many circumstances will get stored in sv
's IV slot, but not in all cases. (Use "sv_setiv"
to make sure it does).
SvIVx
is different from the others in that it is guaranteed to evaluate sv
exactly once; the others may evaluate it multiple times. Only use this form if sv
is an expression with side effects, otherwise use the more efficient SvIV
.
SvIV_nomg
is the same as SvIV
, but does not perform 'get' magic.
IV SvIV(SV* sv)
SvIV_set
Set the value of the IV pointer in sv to val. It is possible to perform the same function of this macro with an lvalue assignment to SvIVX
. With future Perls, however, it will be more efficient to use SvIV_set
instead of the lvalue assignment to SvIVX
.
void SvIV_set(SV* sv, IV val)
SvIVX
Returns the raw value in the SV's IV slot, without checks or conversions. Only use when you are sure SvIOK
is true. See also "SvIV"
.
IV SvIVX(SV* sv)
SvLEN
Returns the size of the string buffer in the SV, not including any part attributable to SvOOK
. See "SvCUR"
.
STRLEN SvLEN(SV* sv)
sv_len
Returns the length of the string in the SV. Handles magic and type coercion and sets the UTF8 flag appropriately. See also "SvCUR"
, which gives raw access to the xpv_cur
slot.
STRLEN sv_len(SV *const sv)
SvLEN_set
Set the size of the string buffer for the SV. See "SvLEN"
.
void SvLEN_set(SV* sv, STRLEN len)
sv_len_utf8
sv_len_utf8_nomg
These return the number of characters in the string in an SV, counting wide UTF-8 bytes as a single character. Both handle type coercion. They differ only in that sv_len_utf8
performs 'get' magic; sv_len_utf8_nomg
skips any magic.
STRLEN sv_len_utf8(SV *const sv)
SvLOCK
Arranges for a mutual exclusion lock to be obtained on sv
if a suitable module has been loaded.
void SvLOCK(SV* sv)
sv_magic
Adds magic to an SV. First upgrades sv
to type SVt_PVMG
if necessary, then adds a new magic item of type how
to the head of the magic list.
See "sv_magicext"
(which sv_magic
now calls) for a description of the handling of the name
and namlen
arguments.
You need to use sv_magicext
to add magic to SvREADONLY
SVs and also to add more than one instance of the same how
.
void sv_magic(SV *const sv, SV *const obj, const int how, const char *const name, const I32 namlen)
sv_magicext
Adds magic to an SV, upgrading it if necessary. Applies the supplied vtable
and returns a pointer to the magic added.
Note that sv_magicext
will allow things that sv_magic
will not. In particular, you can add magic to SvREADONLY
SVs, and add more than one instance of the same how
.
If namlen
is greater than zero then a savepvn
copy of name
is stored, if namlen
is zero then name
is stored as-is and - as another special case - if (name && namlen == HEf_SVKEY)
then name
is assumed to contain an SV* and is stored as-is with its REFCNT
incremented.
(This is now used as a subroutine by sv_magic
.)
MAGIC * sv_magicext(SV *const sv, SV *const obj, const int how, const MGVTBL *const vtbl, const char *const name, const I32 namlen)
SvMAGIC_set
Set the value of the MAGIC pointer in sv
to val. See "SvIV_set"
.
void SvMAGIC_set(SV* sv, MAGIC* val)
sv_mortalcopy
Creates a new SV which is a copy of the original SV (using sv_setsv
). The new SV is marked as mortal. It will be destroyed "soon", either by an explicit call to FREETMPS
, or by an implicit call at places such as statement boundaries. See also "sv_newmortal"
and "sv_2mortal"
.
SV* sv_mortalcopy(SV *const oldsv)
sv_mortalcopy_flags
Like sv_mortalcopy
, but the extra flags
are passed to the sv_setsv_flags
.
SV* sv_mortalcopy_flags(SV *const oldsv, U32 flags)
sv_newmortal
Creates a new null SV which is mortal. The reference count of the SV is set to 1. It will be destroyed "soon", either by an explicit call to FREETMPS
, or by an implicit call at places such as statement boundaries. See also "sv_mortalcopy"
and "sv_2mortal"
.
SV* sv_newmortal()
SvNIOK
Returns a U32 value indicating whether the SV contains a number, integer or double.
U32 SvNIOK(SV* sv)
SvNIOKp
Returns a U32 value indicating whether the SV contains a number, integer or double. Checks the private setting. Use SvNIOK
instead.
U32 SvNIOKp(SV* sv)
SvNOKp
Returns a U32 value indicating whether the SV contains a double. Checks the private setting. Use SvNOK
instead.
U32 SvNOKp(SV* sv)
sv_nolocking
DEPRECATED!
It is planned to remove sv_nolocking
from a future release of Perl. Do not use it for new code; remove it from existing code.
Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing()
.
void sv_nolocking(SV *sv)
sv_nounlocking
DEPRECATED!
It is planned to remove sv_nounlocking
from a future release of Perl. Do not use it for new code; remove it from existing code.
Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" by sv_nosharing()
.
void sv_nounlocking(SV *sv)
sv_numeq
A convenient shortcut for calling sv_numeq_flags
with the SV_GMAGIC
flag. This function basically behaves like the Perl code $sv1 == $sv2
.
bool sv_numeq(SV* sv1, SV* sv2)
sv_numeq_flags
Returns a boolean indicating whether the numbers in the two SVs are identical. If the flags argument has the SV_GMAGIC
bit set, it handles get-magic too. Will coerce its args to numbers if necessary. Treats NULL
as undef.
If flags does not have the SV_SKIP_OVERLOAD
bit set, an attempt to use ==
overloading will be made. If such overloading does not exist or the flag is set, then regular numerical comparison will be used instead.
bool sv_numeq_flags(SV* sv1, SV* sv2, const U32 flags)
SvNV
SvNVx
SvNV_nomg
These coerce the given SV to NV and return it. The returned value in many circumstances will get stored in sv
's NV slot, but not in all cases. (Use "sv_setnv"
to make sure it does).
SvNVx
is different from the others in that it is guaranteed to evaluate sv
exactly once; the others may evaluate it multiple times. Only use this form if sv
is an expression with side effects, otherwise use the more efficient SvNV
.
SvNV_nomg
is the same as SvNV
, but does not perform 'get' magic.
NV SvNV(SV* sv)
SvNV_set
Set the value of the NV pointer in sv
to val. See "SvIV_set"
.
void SvNV_set(SV* sv, NV val)
SvNVX
Returns the raw value in the SV's NV slot, without checks or conversions. Only use when you are sure SvNOK
is true. See also "SvNV"
.
NV SvNVX(SV* sv)
SvOK
Returns a U32 value indicating whether the value is defined. This is only meaningful for scalars.
U32 SvOK(SV* sv)
SvOOK
Returns a U32 indicating whether the pointer to the string buffer is offset. This hack is used internally to speed up removal of characters from the beginning of a "SvPV"
. When SvOOK
is true, then the start of the allocated string buffer is actually SvOOK_offset()
bytes before SvPVX
. This offset used to be stored in SvIVX
, but is now stored within the spare part of the buffer.
U32 SvOOK(SV* sv)
SvOOK_offset
Reads into len
the offset from SvPVX
back to the true start of the allocated buffer, which will be non-zero if sv_chop
has been used to efficiently remove characters from start of the buffer. Implemented as a macro, which takes the address of len
, which must be of type STRLEN
. Evaluates sv
more than once. Sets len
to 0 if SvOOK(sv)
is false.
void SvOOK_offset(SV*sv, STRLEN len)
SvPOK_only
Tells an SV that it is a string and disables all other OK
bits. Will also turn off the UTF-8 status.
void SvPOK_only(SV* sv)
SvPOK_only_UTF8
Tells an SV that it is a string and disables all other OK
bits, and leaves the UTF-8 status as it was.
void SvPOK_only_UTF8(SV* sv)
SvPOKp
Returns a U32 value indicating whether the SV contains a character string. Checks the private setting. Use SvPOK
instead.
U32 SvPOKp(SV* sv)
sv_pos_b2u
Converts the value pointed to by offsetp
from a count of bytes from the start of the string, to a count of the equivalent number of UTF-8 chars. Handles magic and type coercion.
Use sv_pos_b2u_flags
in preference, which correctly handles strings longer than 2Gb.
void sv_pos_b2u(SV *const sv, I32 *const offsetp)
sv_pos_b2u_flags
Converts offset
from a count of bytes from the start of the string, to a count of the equivalent number of UTF-8 chars. Handles type coercion. flags
is passed to SvPV_flags
, and usually should be SV_GMAGIC|SV_CONST_RETURN
to handle magic.
STRLEN sv_pos_b2u_flags(SV *const sv, STRLEN const offset, U32 flags)
sv_pos_u2b
Converts the value pointed to by offsetp
from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; if lenp
is non-zero, it does the same to lenp
, but this time starting from the offset, rather than from the start of the string. Handles magic and type coercion.
Use sv_pos_u2b_flags
in preference, which correctly handles strings longer than 2Gb.
void sv_pos_u2b(SV *const sv, I32 *const offsetp, I32 *const lenp)
sv_pos_u2b_flags
Converts the offset from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; if lenp
is non-zero, it does the same to lenp
, but this time starting from offset
, rather than from the start of the string. Handles type coercion. flags
is passed to SvPV_flags
, and usually should be SV_GMAGIC|SV_CONST_RETURN
to handle magic.
STRLEN sv_pos_u2b_flags(SV *const sv, STRLEN uoffset, STRLEN *const lenp, U32 flags)
SvPV
SvPVx
SvPV_nomg
SvPV_nolen
SvPVx_nolen
SvPV_nomg_nolen
SvPV_mutable
SvPV_const
SvPVx_const
SvPV_nolen_const
SvPVx_nolen_const
SvPV_nomg_const
SvPV_nomg_const_nolen
SvPV_flags
SvPV_flags_const
SvPV_flags_mutable
SvPVbyte
SvPVbyte_nomg
SvPVbyte_nolen
SvPVbytex_nolen
SvPVbytex
SvPVbyte_or_null
SvPVbyte_or_null_nomg
SvPVutf8
SvPVutf8x
SvPVutf8_nomg
SvPVutf8_nolen
SvPVutf8_or_null
SvPVutf8_or_null_nomg
All these return a pointer to the string in sv
, or a stringified form of sv
if it does not contain a string. The SV may cache the stringified version becoming SvPOK
.
This is a very basic and common operation, so there are lots of slightly different versions of it.
Note that there is no guarantee that the return value of SvPV(sv)
, for example, is equal to SvPVX(sv)
, or that SvPVX(sv)
contains valid data, or that successive calls to SvPV(sv)
(or another of these forms) will return the same pointer value each time. This is due to the way that things like overloading and Copy-On-Write are handled. In these cases, the return value may point to a temporary buffer or similar. If you absolutely need the SvPVX
field to be valid (for example, if you intend to write to it), then see "SvPV_force"
.
The differences between the forms are:
The forms with neither byte
nor utf8
in their names (e.g., SvPV
or SvPV_nolen
) can expose the SV's internal string buffer. If that buffer consists entirely of bytes 0-255 and includes any bytes above 127, then you MUST consult SvUTF8
to determine the actual code points the string is meant to contain. Generally speaking, it is probably safer to prefer SvPVbyte
, SvPVutf8
, and the like. See "How do I pass a Perl string to a C library?" in perlguts for more details.
The forms with flags
in their names allow you to use the flags
parameter to specify to process 'get' magic (by setting the SV_GMAGIC
flag) or to skip 'get' magic (by clearing it). The other forms process 'get' magic, except for the ones with nomg
in their names, which skip 'get' magic.
The forms that take a len
parameter will set that variable to the byte length of the resultant string (these are macros, so don't use &len
).
The forms with nolen
in their names indicate they don't have a len
parameter. They should be used only when it is known that the PV is a C string, terminated by a NUL byte, and without intermediate NUL characters; or when you don't care about its length.
The forms with const
in their names return
so that the compiler will hopefully complain if you were to try to modify the contents of the string (unless you cast away const yourself).const char *
The other forms return a mutable pointer so that the string is modifiable by the caller; this is emphasized for the ones with mutable
in their names.
The forms whose name ends in x
are the same as the corresponding form without the x
, but the x
form is guaranteed to evaluate sv
exactly once, with a slight loss of efficiency. Use this if sv
is an expression with side effects.
SvPVutf8
is like SvPV
, but converts sv
to UTF-8 first if not already UTF-8. Similiarly, the other forms with utf8
in their names correspond to their respective forms without.
SvPVutf8_or_null
and SvPVutf8_or_null_nomg
don't have corresponding non-utf8
forms. Instead they are like SvPVutf8_nomg
, but when sv
is undef, they return NULL
.
SvPVbyte
is like SvPV
, but converts sv
to byte representation first if currently encoded as UTF-8. If sv
cannot be downgraded from UTF-8, it croaks. Similiarly, the other forms with byte
in their names correspond to their respective forms without.
SvPVbyte_or_null
doesn't have a corresponding non-byte
form. Instead it is like SvPVbyte
, but when sv
is undef, it returns NULL
.
char* SvPV (SV* sv, STRLEN len) char* SvPVx (SV* sv, STRLEN len) char* SvPV_nomg (SV* sv, STRLEN len) char* SvPV_nolen (SV* sv) char* SvPVx_nolen (SV* sv) char* SvPV_nomg_nolen (SV* sv) char* SvPV_mutable (SV* sv, STRLEN len) const char* SvPV_const (SV* sv, STRLEN len) const char* SvPVx_const (SV* sv, STRLEN len) const char* SvPV_nolen_const (SV* sv) const char* SvPVx_nolen_const (SV* sv) const char* SvPV_nomg_const (SV* sv, STRLEN len) const char* SvPV_nomg_const_nolen(SV* sv) char * SvPV_flags (SV * sv, STRLEN len, U32 flags) const char * SvPV_flags_const (SV * sv, STRLEN len, U32 flags) char * SvPV_flags_mutable (SV * sv, STRLEN len, U32 flags) char* SvPVbyte (SV* sv, STRLEN len) char* SvPVbyte_nomg (SV* sv, STRLEN len) char* SvPVbyte_nolen (SV* sv) char* SvPVbytex_nolen (SV* sv) char* SvPVbytex (SV* sv, STRLEN len) char* SvPVbyte_or_null (SV* sv, STRLEN len) char* SvPVbyte_or_null_nomg(SV* sv, STRLEN len) char* SvPVutf8 (SV* sv, STRLEN len) char* SvPVutf8x (SV* sv, STRLEN len) char* SvPVutf8_nomg (SV* sv, STRLEN len) char* SvPVutf8_nolen (SV* sv) char* SvPVutf8_or_null (SV* sv, STRLEN len) char* SvPVutf8_or_null_nomg(SV* sv, STRLEN len)
SvPVCLEAR
Ensures that sv is a SVt_PV and that its SvCUR is 0, and that it is properly null terminated. Equivalent to sv_setpvs(""), but more efficient.
char * SvPVCLEAR(SV* sv)
SvPV_force
SvPV_force_nolen
SvPVx_force
SvPV_force_nomg
SvPV_force_nomg_nolen
SvPV_force_mutable
SvPV_force_flags
SvPV_force_flags_nolen
SvPV_force_flags_mutable
SvPVbyte_force
SvPVbytex_force
SvPVutf8_force
SvPVutf8x_force
These are like "SvPV"
, returning the string in the SV, but will force the SV into containing a string ("SvPOK"
), and only a string ("SvPOK_only"
), by hook or by crook. You need to use one of these force
routines if you are going to update the "SvPVX"
directly.
Note that coercing an arbitrary scalar into a plain PV will potentially strip useful data from it. For example if the SV was SvROK
, then the referent will have its reference count decremented, and the SV itself may be converted to an SvPOK
scalar with a string buffer containing a value such as "ARRAY(0x1234)"
.
The differences between the forms are:
The forms with flags
in their names allow you to use the flags
parameter to specify to perform 'get' magic (by setting the SV_GMAGIC
flag) or to skip 'get' magic (by clearing it). The other forms do perform 'get' magic, except for the ones with nomg
in their names, which skip 'get' magic.
The forms that take a len
parameter will set that variable to the byte length of the resultant string (these are macros, so don't use &len
).
The forms with nolen
in their names indicate they don't have a len
parameter. They should be used only when it is known that the PV is a C string, terminated by a NUL byte, and without intermediate NUL characters; or when you don't care about its length.
The forms with mutable
in their names are effectively the same as those without, but the name emphasizes that the string is modifiable by the caller, which it is in all the forms.
SvPVutf8_force
is like SvPV_force
, but converts sv
to UTF-8 first if not already UTF-8.
SvPVutf8x_force
is like SvPVutf8_force
, but guarantees to evaluate sv
only once; use the more efficient SvPVutf8_force
otherwise.
SvPVbyte_force
is like SvPV_force
, but converts sv
to byte representation first if currently encoded as UTF-8. If the SV cannot be downgraded from UTF-8, this croaks.
SvPVbytex_force
is like SvPVbyte_force
, but guarantees to evaluate sv
only once; use the more efficient SvPVbyte_force
otherwise.
char* SvPV_force (SV* sv, STRLEN len) char* SvPV_force_nolen (SV* sv) char* SvPVx_force (SV* sv, STRLEN len) char* SvPV_force_nomg (SV* sv, STRLEN len) char* SvPV_force_nomg_nolen (SV * sv) char* SvPV_force_mutable (SV * sv, STRLEN len) char* SvPV_force_flags (SV * sv, STRLEN len, U32 flags) char* SvPV_force_flags_nolen (SV * sv, U32 flags) char* SvPV_force_flags_mutable(SV * sv, STRLEN len, U32 flags) char* SvPVbyte_force (SV* sv, STRLEN len) char* SvPVbytex_force (SV* sv, STRLEN len) char* SvPVutf8_force (SV* sv, STRLEN len) char* SvPVutf8x_force (SV* sv, STRLEN len)
SvPV_free
Frees the PV buffer in sv
, leaving things in a precarious state, so should only be used as part of a larger operation
void SvPV_free(SV * sv)
sv_pvn_force_flags
Get a sensible string out of the SV somehow. If flags
has the SV_GMAGIC
bit set, will "mg_get"
on sv
if appropriate, else not. sv_pvn_force
and sv_pvn_force_nomg
are implemented in terms of this function. You normally want to use the various wrapper macros instead: see "SvPV_force"
and "SvPV_force_nomg"
.
char* sv_pvn_force_flags(SV *const sv, STRLEN *const lp, const U32 flags)
SvPV_renew
Low level micro optimization of "SvGROW"
. It is generally better to use SvGROW
instead. This is because SvPV_renew
ignores potential issues that SvGROW
handles. sv
needs to have a real PV
that is unencombered by things like COW. Using SV_CHECK_THINKFIRST
or SV_CHECK_THINKFIRST_COW_DROP
before calling this should clean it up, but why not just use SvGROW
if you're not sure about the provenance?
void SvPV_renew(SV* sv, STRLEN len)
SvPV_set
This is probably not what you want to use, you probably wanted "sv_usepvn_flags" or "sv_setpvn" or "sv_setpvs".
Set the value of the PV pointer in sv
to the Perl allocated NUL
-terminated string val
. See also "SvIV_set"
.
Remember to free the previous PV buffer. There are many things to check. Beware that the existing pointer may be involved in copy-on-write or other mischief, so do SvOOK_off(sv)
and use sv_force_normal
or SvPV_force
(or check the SvIsCOW
flag) first to make sure this modification is safe. Then finally, if it is not a COW, call "SvPV_free"
to free the previous PV buffer.
void SvPV_set(SV* sv, char* val)
SvPVX
SvPVXx
SvPVX_const
SvPVX_mutable
These return a pointer to the physical string in the SV. The SV must contain a string. Prior to 5.9.3 it is not safe to execute these unless the SV's type >= SVt_PV
.
These are also used to store the name of an autoloaded subroutine in an XS AUTOLOAD routine. See "Autoloading with XSUBs" in perlguts.
SvPVXx
is identical to SvPVX
.
SvPVX_mutable
is merely a synonym for SvPVX
, but its name emphasizes that the string is modifiable by the caller.
SvPVX_const
differs in that the return value has been cast so that the compiler will complain if you were to try to modify the contents of the string, (unless you cast away const yourself).
char* SvPVX (SV* sv) char* SvPVXx (SV* sv) const char* SvPVX_const (SV* sv) char* SvPVX_mutable(SV* sv)
SvPVXtrue
Note: This macro may evaluate sv
more than once.
Returns a boolean as to whether or not sv
contains a PV that is considered TRUE. FALSE is returned if sv
doesn't contain a PV, or if the PV it does contain is zero length, or consists of just the single character '0'. Every other PV value is considered TRUE.
bool SvPVXtrue(SV * sv)
SvREADONLY
Returns true if the argument is readonly, otherwise returns false. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY(SV* sv)
SvREADONLY_off
Mark an object as not-readonly. Exactly what this mean depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_off(SV* sv)
SvREADONLY_on
Mark an object as readonly. Exactly what this means depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32 SvREADONLY_on(SV* sv)
sv_ref
Returns a SV describing what the SV passed in is a reference to.
dst can be a SV to be set to the description or NULL, in which case a mortal SV is returned.
If ob is true and the SV is blessed, the description is the class name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
SV* sv_ref(SV *dst, const SV *const sv, const int ob)
SvREFCNT
Returns the value of the object's reference count. Exposed to perl code via Internals::SvREFCNT().
U32 SvREFCNT(SV* sv)
SvREFCNT_dec
SvREFCNT_dec_NN
These decrement the reference count of the given SV.
SvREFCNT_dec_NN
may only be used when sv
is known to not be NULL
.
void SvREFCNT_dec(SV *sv)
SvREFCNT_inc
SvREFCNT_inc_NN
SvREFCNT_inc_void
SvREFCNT_inc_void_NN
SvREFCNT_inc_simple
SvREFCNT_inc_simple_NN
SvREFCNT_inc_simple_void
SvREFCNT_inc_simple_void_NN
These all increment the reference count of the given SV. The ones without void
in their names return the SV.
SvREFCNT_inc
is the base operation; the rest are optimizations if various input constraints are known to be true; hence, all can be replaced with SvREFCNT_inc
.
SvREFCNT_inc_NN
can only be used if you know sv
is not NULL
. Since we don't have to check the NULLness, it's faster and smaller.
SvREFCNT_inc_void
can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
SvREFCNT_inc_void_NN
can only be used if you both don't need the return value, and you know that sv
is not NULL
. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
SvREFCNT_inc_simple
can only be used with expressions without side effects. Since we don't have to store a temporary value, it's faster.
SvREFCNT_inc_simple_NN
can only be used with expressions without side effects and you know sv
is not NULL
. Since we don't have to store a temporary value, nor check for NULLness, it's faster and smaller.
SvREFCNT_inc_simple_void
can only be used with expressions without side effects and you don't need the return value.
SvREFCNT_inc_simple_void_NN
can only be used with expressions without side effects, you don't need the return value, and you know sv
is not NULL
.
SV * SvREFCNT_inc (SV *sv) SV * SvREFCNT_inc_NN (SV *sv) void SvREFCNT_inc_void (SV *sv) void SvREFCNT_inc_void_NN (SV* sv) SV* SvREFCNT_inc_simple (SV* sv) SV* SvREFCNT_inc_simple_NN (SV* sv) void SvREFCNT_inc_simple_void (SV* sv) void SvREFCNT_inc_simple_void_NN(SV* sv)
sv_reftype
Returns a string describing what the SV is a reference to.
If ob is true and the SV is blessed, the string is the class name, otherwise it is the type of the SV, "SCALAR", "ARRAY" etc.
const char* sv_reftype(const SV *const sv, const int ob)
sv_replace
Make the first argument a copy of the second, then delete the original. The target SV physically takes over ownership of the body of the source SV and inherits its flags; however, the target keeps any magic it owns, and any magic in the source is discarded. Note that this is a rather specialist SV copying operation; most of the time you'll want to use sv_setsv
or one of its many macro front-ends.
void sv_replace(SV *const sv, SV *const nsv)
sv_reset
Underlying implementation for the reset
Perl function. Note that the perl-level function is vaguely deprecated.
void sv_reset(const char* s, HV *const stash)
SvRV_set
Set the value of the RV pointer in sv
to val. See "SvIV_set"
.
void SvRV_set(SV* sv, SV* val)
sv_rvunweaken
Unweaken a reference: Clear the SvWEAKREF
flag on this RV; remove the backreference to this RV from the array of backreferences associated with the target SV, increment the refcount of the target. Silently ignores undef
and warns on non-weak references.
SV* sv_rvunweaken(SV *const sv)
sv_rvweaken
Weaken a reference: set the SvWEAKREF
flag on this RV; give the referred-to SV PERL_MAGIC_backref
magic if it hasn't already; and push a back-reference to this RV onto the array of backreferences associated with that magic. If the RV is magical, set magic will be called after the RV is cleared. Silently ignores undef
and warns on already-weak references.
SV* sv_rvweaken(SV *const sv)
sv_setbool
sv_setbool_mg
These set an SV to a true or false boolean value, upgrading first if necessary.
They differ only in that sv_setbool_mg
handles 'set' magic; sv_setbool
does not.
void sv_setbool(SV *sv, bool b)
sv_setiv
sv_setiv_mg
These copy an integer into the given SV, upgrading first if necessary.
They differ only in that sv_setiv_mg
handles 'set' magic; sv_setiv
does not.
void sv_setiv (SV *const sv, const IV num) void sv_setiv_mg(SV *const sv, const IV i)
SvSETMAGIC
Invokes "mg_set"
on an SV if it has 'set' magic. This is necessary after modifying a scalar, in case it is a magical variable like $|
or a tied variable (it calls STORE
). This macro evaluates its argument more than once.
void SvSETMAGIC(SV* sv)
sv_setnv
sv_setnv_mg
These copy a double into the given SV, upgrading first if necessary.
They differ only in that sv_setnv_mg
handles 'set' magic; sv_setnv
does not.
void sv_setnv(SV *const sv, const NV num)
sv_setpv
sv_setpv_mg
sv_setpvn
sv_setpvn_fresh
sv_setpvn_mg
sv_setpvs
sv_setpvs_mg
These copy a string into the SV sv
, making sure it is "SvPOK_only"
.
In the pvs
forms, the string must be a C literal string, enclosed in double quotes.
In the pvn
forms, the first byte of the string is pointed to by ptr
, and len
indicates the number of bytes to be copied, potentially including embedded NUL
characters.
In the plain pv
forms, ptr
points to a NUL-terminated C string. That is, it points to the first byte of the string, and the copy proceeds up through the first enountered NUL
byte.
In the forms that take a ptr
argument, if it is NULL, the SV will become undefined.
The UTF-8 flag is not changed by these functions. A terminating NUL byte is guaranteed in the result.
The _mg
forms handle 'set' magic; the other forms skip all magic.
sv_setpvn_fresh
is a cut-down alternative to sv_setpvn
, intended ONLY to be used with a fresh sv that has been upgraded to a SVt_PV, SVt_PVIV, SVt_PVNV, or SVt_PVMG.
void sv_setpv (SV *const sv, const char *const ptr) void sv_setpv_mg (SV *const sv, const char *const ptr) void sv_setpvn (SV *const sv, const char *const ptr, const STRLEN len) void sv_setpvn_fresh(SV *const sv, const char *const ptr, const STRLEN len) void sv_setpvn_mg (SV *const sv, const char *const ptr, const STRLEN len) void sv_setpvs (SV* sv, "literal string") void sv_setpvs_mg (SV* sv, "literal string")
sv_setpvf
sv_setpvf_nocontext
sv_setpvf_mg
sv_setpvf_mg_nocontext
These work like "sv_catpvf"
but copy the text into the SV instead of appending it.
The differences between these are:
sv_setpvf_mg
and sv_setpvf_mg_nocontext
perform 'set' magic; sv_setpvf
and sv_setpvf_nocontext
skip all magic.
sv_setpvf_nocontext
and sv_setpvf_mg_nocontext
do not take a thread context (aTHX
) parameter, so are used in situations where the caller doesn't already have the thread context.
NOTE: sv_setpvf
must be explicitly called as Perl_sv_setpvf
with an aTHX_
parameter.
NOTE: sv_setpvf_mg
must be explicitly called as Perl_sv_setpvf_mg
with an aTHX_
parameter.
void Perl_sv_setpvf (pTHX_ SV *const sv, const char *const pat, ...) void sv_setpvf_nocontext (SV *const sv, const char *const pat, ...) void Perl_sv_setpvf_mg (pTHX_ SV *const sv, const char *const pat, ...) void sv_setpvf_mg_nocontext(SV *const sv, const char *const pat, ...)
sv_setpviv
sv_setpviv_mg
DEPRECATED!
It is planned to remove both forms from a future release of Perl. Do not use them for new code; remove them from existing code.
These copy an integer into the given SV, also updating its string value.
They differ only in that sv_setpviv_mg
performs 'set' magic; sv_setpviv
skips any magic.
void sv_setpviv (SV *const sv, const IV num) void sv_setpviv_mg(SV *const sv, const IV iv)
sv_setpv_bufsize
Sets the SV to be a string of cur bytes length, with at least len bytes available. Ensures that there is a null byte at SvEND. Returns a char * pointer to the SvPV buffer.
char * sv_setpv_bufsize(SV *const sv, const STRLEN cur, const STRLEN len)
sv_setref_iv
Copies an integer into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV* sv_setref_iv(SV *const rv, const char *const classname, const IV iv)
sv_setref_nv
Copies a double into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV* sv_setref_nv(SV *const rv, const char *const classname, const NV nv)
sv_setref_pv
Copies a pointer into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. If the pv
argument is NULL
, then PL_sv_undef
will be placed into the SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Do not use with other Perl types such as HV, AV, SV, CV, because those objects will become corrupted by the pointer copy process.
Note that sv_setref_pvn
copies the string while this copies the pointer.
SV* sv_setref_pv(SV *const rv, const char *const classname, void *const pv)
sv_setref_pvn
Copies a string into a new SV, optionally blessing the SV. The length of the string must be specified with n
. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Note that sv_setref_pv
copies the pointer while this copies the string.
SV* sv_setref_pvn(SV *const rv, const char *const classname, const char *const pv, const STRLEN n)
sv_setref_pvs
Like sv_setref_pvn
, but takes a literal string instead of a string/length pair.
SV * sv_setref_pvs(SV *const rv, const char *const classname, "literal string")
sv_setref_uv
Copies an unsigned integer into a new SV, optionally blessing the SV. The rv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. The classname
argument indicates the package for the blessing. Set classname
to NULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
SV* sv_setref_uv(SV *const rv, const char *const classname, const UV uv)
sv_setrv_inc
sv_setrv_inc_mg
As sv_setrv_noinc
but increments the reference count of ref.
sv_setrv_inc_mg
will invoke 'set' magic on the SV; sv_setrv_inc
will not.
void sv_setrv_inc(SV *const sv, SV *const ref)
sv_setrv_noinc
sv_setrv_noinc_mg
Copies an SV pointer into the given SV as an SV reference, upgrading it if necessary. After this, SvRV(sv)
is equal to ref. This does not adjust the reference count of ref. The reference ref must not be NULL.
sv_setrv_noinc_mg
will invoke 'set' magic on the SV; sv_setrv_noinc
will not.
void sv_setrv_noinc(SV *const sv, SV *const ref)
SvSetSV
SvSetMagicSV
SvSetSV_nosteal
SvSetMagicSV_nosteal
if dsv
is the same as ssv
, these do nothing. Otherwise they all call some form of "sv_setsv"
. They may evaluate their arguments more than once.
The only differences are:
SvSetMagicSV
and SvSetMagicSV_nosteal
perform any required 'set' magic afterwards on the destination SV; SvSetSV
and SvSetSV_nosteal
do not.
SvSetSV_nosteal
SvSetMagicSV_nosteal
call a non-destructive version of sv_setsv
.
void SvSetSV(SV* dsv, SV* ssv)
sv_setsv
sv_setsv_flags
sv_setsv_mg
sv_setsv_nomg
These copy the contents of the source SV ssv
into the destination SV dsv
. ssv
may be destroyed if it is mortal, so don't use these functions if the source SV needs to be reused. Loosely speaking, they perform a copy-by-value, obliterating any previous content of the destination.
They differ only in that:
sv_setsv
calls 'get' magic on ssv
, but skips 'set' magic on dsv
.
sv_setsv_mg
calls both 'get' magic on ssv
and 'set' magic on dsv
.
sv_setsv_nomg
skips all magic.
sv_setsv_flags
has a flags
parameter which you can use to specify any combination of magic handling, and also you can specify SV_NOSTEAL
so that the buffers of temps will not be stolen.
You probably want to instead use one of the assortment of wrappers, such as "SvSetSV"
, "SvSetSV_nosteal"
, "SvSetMagicSV"
and "SvSetMagicSV_nosteal"
.
sv_setsv_flags
is the primary function for copying scalars, and most other copy-ish functions and macros use it underneath.
void sv_setsv (SV *dsv, SV *ssv) void sv_setsv_flags(SV *dsv, SV *ssv, const I32 flags) void sv_setsv_mg (SV *const dsv, SV *const ssv) void sv_setsv_nomg (SV *dsv, SV *ssv)
sv_setuv
sv_setuv_mg
These copy an unsigned integer into the given SV, upgrading first if necessary.
They differ only in that sv_setuv_mg
handles 'set' magic; sv_setuv
does not.
void sv_setuv (SV *const sv, const UV num) void sv_setuv_mg(SV *const sv, const UV u)
sv_set_undef
Equivalent to sv_setsv(sv, &PL_sv_undef)
, but more efficient. Doesn't handle set magic.
The perl equivalent is $sv = undef;
. Note that it doesn't free any string buffer, unlike undef $sv
.
Introduced in perl 5.25.12.
void sv_set_undef(SV *sv)
SvSHARE
Arranges for sv
to be shared between threads if a suitable module has been loaded.
void SvSHARE(SV* sv)
SvSHARED_HASH
Returns the hash for sv
created by "newSVpvn_share"
.
struct hek* SvSHARED_HASH(SV * sv)
SvSTASH_set
Set the value of the STASH pointer in sv
to val. See "SvIV_set"
.
void SvSTASH_set(SV* sv, HV* val)
sv_streq
A convenient shortcut for calling sv_streq_flags
with the SV_GMAGIC
flag. This function basically behaves like the Perl code $sv1 eq $sv2
.
bool sv_streq(SV* sv1, SV* sv2)
sv_streq_flags
Returns a boolean indicating whether the strings in the two SVs are identical. If the flags argument has the SV_GMAGIC
bit set, it handles get-magic too. Will coerce its args to strings if necessary. Treats NULL
as undef. Correctly handles the UTF8 flag.
If flags does not have the SV_SKIP_OVERLOAD
bit set, an attempt to use eq
overloading will be made. If such overloading does not exist or the flag is set, then regular string comparison will be used instead.
bool sv_streq_flags(SV* sv1, SV* sv2, const U32 flags)
SvTRUE
SvTRUEx
SvTRUE_nomg
SvTRUE_NN
SvTRUE_nomg_NN
These return a boolean indicating whether Perl would evaluate the SV as true or false. See "SvOK"
for a defined/undefined test.
As of Perl 5.32, all are guaranteed to evaluate sv
only once. Prior to that release, only SvTRUEx
guaranteed single evaluation; now SvTRUEx
is identical to SvTRUE
.
SvTRUE_nomg
and TRUE_nomg_NN
do not perform 'get' magic; the others do unless the scalar is already SvPOK
, SvIOK
, or SvNOK
(the public, not the private flags).
SvTRUE_NN
is like "SvTRUE"
, but sv
is assumed to be non-null (NN). If there is a possibility that it is NULL, use plain SvTRUE
.
SvTRUE_nomg_NN
is like "SvTRUE_nomg"
, but sv
is assumed to be non-null (NN). If there is a possibility that it is NULL, use plain SvTRUE_nomg
.
bool SvTRUE(SV *sv)
SvTYPE
Returns the type of the SV. See "svtype"
.
svtype SvTYPE(SV* sv)
SvUNLOCK
Releases a mutual exclusion lock on sv
if a suitable module has been loaded.
void SvUNLOCK(SV* sv)
sv_unmagicext
Removes all magic of type type
with the specified vtbl
from an SV.
int sv_unmagicext(SV *const sv, const int type, MGVTBL *vtbl)
sv_unref
Unsets the RV status of the SV, and decrements the reference count of whatever was being referenced by the RV. This can almost be thought of as a reversal of newSVrv
. This is sv_unref_flags
with the flag
being zero. See "SvROK_off"
.
void sv_unref(SV* sv)
sv_unref_flags
Unsets the RV status of the SV, and decrements the reference count of whatever was being referenced by the RV. This can almost be thought of as a reversal of newSVrv
. The cflags
argument can contain SV_IMMEDIATE_UNREF
to force the reference count to be decremented (otherwise the decrementing is conditional on the reference count being different from one or the reference being a readonly SV). See "SvROK_off"
.
void sv_unref_flags(SV *const ref, const U32 flags)
SvUOK
Returns a boolean indicating whether the SV contains an integer that must be interpreted as unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be flagged as either SvUOK
or SvIOK
.
bool SvUOK(SV* sv)
SvUPGRADE
Used to upgrade an SV to a more complex form. Uses sv_upgrade
to perform the upgrade if necessary. See "svtype"
.
void SvUPGRADE(SV* sv, svtype type)
sv_upgrade
Upgrade an SV to a more complex form. Generally adds a new body type to the SV, then copies across as much information as possible from the old body. It croaks if the SV is already in a more complex form than requested. You generally want to use the SvUPGRADE
macro wrapper, which checks the type before calling sv_upgrade
, and hence does not croak. See also "svtype"
.
void sv_upgrade(SV *const sv, svtype new_type)
sv_usepvn
sv_usepvn_mg
sv_usepvn_flags
These tell an SV to use ptr
for its string value. Normally SVs have their string stored inside the SV, but these tell the SV to use an external string instead.
ptr
should point to memory that was allocated by "Newx
". It must be the start of a Newx
-ed block of memory, and not a pointer to the middle of it (beware of OOK
and copy-on-write), and not be from a non-Newx
memory allocator like malloc
. The string length, len
, must be supplied. By default this function will "Renew
" (i.e. realloc, move) the memory pointed to by ptr
, so that the pointer should not be freed or used by the programmer after giving it to sv_usepvn
, and neither should any pointers from "behind" that pointer (e.g.,
) be used.ptr
+ 1
In the sv_usepvn_flags
form, if
is true, flags & SV_SMAGIC
SvSETMAGIC
is called before returning. And if
is true, then flags & SV_HAS_TRAILING_NUL
ptr[len]
must be NUL
, and the realloc will be skipped (i.e., the buffer is actually at least 1 byte longer than len
, and already meets the requirements for storing in SvPVX
).
sv_usepvn
is merely sv_usepvn_flags
with flags
set to 0, so 'set' magic is skipped.
sv_usepvn_mg
is merely sv_usepvn_flags
with flags
set to SV_SMAGIC
, so 'set' magic is performed.
void sv_usepvn (SV* sv, char* ptr, STRLEN len) void sv_usepvn_mg (SV *sv, char *ptr, STRLEN len) void sv_usepvn_flags(SV *const sv, char* ptr, const STRLEN len, const U32 flags)
SvUTF8
Returns a U32 value indicating the UTF-8 status of an SV. If things are set-up properly, this indicates whether or not the SV contains UTF-8 encoded data. You should use this after a call to "SvPV"
or one of its variants, in case any call to string overloading updates the internal flag.
If you want to take into account the bytes pragma, use "DO_UTF8"
instead.
U32 SvUTF8(SV* sv)
sv_utf8_decode
If the PV of the SV is an octet sequence in Perl's extended UTF-8 and contains a multiple-byte character, the SvUTF8
flag is turned on so that it looks like a character. If the PV contains only single-byte characters, the SvUTF8
flag stays off. Scans PV for validity and returns FALSE if the PV is invalid UTF-8.
bool sv_utf8_decode(SV *const sv)
sv_utf8_downgrade
sv_utf8_downgrade_flags
sv_utf8_downgrade_nomg
These attempt to convert the PV of an SV from characters to bytes. If the PV contains a character that cannot fit in a byte, this conversion will fail; in this case, FALSE
is returned if fail_ok
is true; otherwise they croak.
They are not a general purpose Unicode to byte encoding interface: use the Encode
extension for that.
They differ only in that:
sv_utf8_downgrade
processes 'get' magic on sv
.
sv_utf8_downgrade_nomg
does not.
sv_utf8_downgrade_flags
has an additional flags
parameter in which you can specify SV_GMAGIC
to process 'get' magic, or leave it cleared to not process 'get' magic.
bool sv_utf8_downgrade (SV *const sv, const bool fail_ok) bool sv_utf8_downgrade_flags(SV *const sv, const bool fail_ok, const U32 flags) bool sv_utf8_downgrade_nomg (SV *const sv, const bool fail_ok)
sv_utf8_encode
Converts the PV of an SV to UTF-8, but then turns the SvUTF8
flag off so that it looks like octets again.
void sv_utf8_encode(SV *const sv)
sv_utf8_upgrade
sv_utf8_upgrade_nomg
sv_utf8_upgrade_flags
sv_utf8_upgrade_flags_grow
These convert the PV of an SV to its UTF-8-encoded form. The SV is forced to string form if it is not already. They always set the SvUTF8
flag to avoid future validity checks even if the whole string is the same in UTF-8 as not. They return the number of bytes in the converted string
The forms differ in just two ways. The main difference is whether or not they perform 'get magic' on sv
. sv_utf8_upgrade_nomg
skips 'get magic'; sv_utf8_upgrade
performs it; and sv_utf8_upgrade_flags
and sv_utf8_upgrade_flags_grow
either perform it (if the SV_GMAGIC
bit is set in flags
) or don't (if that bit is cleared).
The other difference is that sv_utf8_upgrade_flags_grow
has an additional parameter, extra
, which allows the caller to specify an amount of space to be reserved as spare beyond what is needed for the actual conversion. This is used when the caller knows it will soon be needing yet more space, and it is more efficient to request space from the system in a single call. This form is otherwise identical to sv_utf8_upgrade_flags
.
These are not a general purpose byte encoding to Unicode interface: use the Encode extension for that.
The SV_FORCE_UTF8_UPGRADE
flag is now ignored.
STRLEN sv_utf8_upgrade (SV *sv) STRLEN sv_utf8_upgrade_nomg (SV *sv) STRLEN sv_utf8_upgrade_flags (SV *const sv, const I32 flags) STRLEN sv_utf8_upgrade_flags_grow(SV *const sv, const I32 flags, STRLEN extra)
SvUTF8_off
Unsets the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_off(SV *sv)
SvUTF8_on
Turn on the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
void SvUTF8_on(SV *sv)
SvUV
SvUVx
SvUV_nomg
These coerce the given SV to UV and return it. The returned value in many circumstances will get stored in sv
's UV slot, but not in all cases. (Use "sv_setuv"
to make sure it does).
SvUVx
is different from the others in that it is guaranteed to evaluate sv
exactly once; the others may evaluate it multiple times. Only use this form if sv
is an expression with side effects, otherwise use the more efficient SvUV
.
SvUV_nomg
is the same as SvUV
, but does not perform 'get' magic.
UV SvUV(SV* sv)
SvUV_set
Set the value of the UV pointer in sv
to val. See "SvIV_set"
.
void SvUV_set(SV* sv, UV val)
SvUVX
Returns the raw value in the SV's UV slot, without checks or conversions. Only use when you are sure SvIOK
is true. See also "SvUV"
.
UV SvUVX(SV* sv)
SvUVXx
DEPRECATED!
It is planned to remove SvUVXx
from a future release of Perl. Do not use it for new code; remove it from existing code.
This is an unnecessary synonym for "SvUVX"
UV SvUVXx(SV* sv)
sv_vcatpvf
sv_vcatpvf_mg
These process their arguments like sv_vcatpvfn
called with a non-null C-style variable argument list, and append the formatted output to sv
.
They differ only in that sv_vcatpvf_mg
performs 'set' magic; sv_vcatpvf
skips 'set' magic.
Both perform 'get' magic.
They are usually accessed via their frontends "sv_catpvf"
and "sv_catpvf_mg"
.
void sv_vcatpvf(SV *const sv, const char *const pat, va_list *const args)
sv_vcatpvfn
sv_vcatpvfn_flags
These process their arguments like vsprintf(3)
and append the formatted output to an SV. They use an array of SVs if the C-style variable argument list is missing (NULL
). Argument reordering (using format specifiers like %2$d
or %*2$d
) is supported only when using an array of SVs; using a C-style va_list
argument list with a format string that uses argument reordering will yield an exception.
When running with taint checks enabled, they indicate via maybe_tainted
if results are untrustworthy (often due to the use of locales).
They assume that pat
has the same utf8-ness as sv
. It's the caller's responsibility to ensure that this is so.
They differ in that sv_vcatpvfn_flags
has a flags
parameter in which you can set or clear the SV_GMAGIC
and/or SV_SMAGIC
flags, to specify which magic to handle or not handle; whereas plain sv_vcatpvfn
always specifies both 'get' and 'set' magic.
They are usually used via one of the frontends "sv_vcatpvf
" and "sv_vcatpvf_mg
".
void sv_vcatpvfn (SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const Size_t sv_count, bool *const maybe_tainted) void sv_vcatpvfn_flags(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const Size_t sv_count, bool *const maybe_tainted, const U32 flags)
sv_vsetpvf
sv_vsetpvf_mg
These work like "sv_vcatpvf"
but copy the text into the SV instead of appending it.
They differ only in that sv_vsetpvf_mg
performs 'set' magic; sv_vsetpvf
skips all magic.
They are usually used via their frontends, "sv_setpvf"
and "sv_setpvf_mg"
.
void sv_vsetpvf(SV *const sv, const char *const pat, va_list *const args)
sv_vsetpvfn
Works like sv_vcatpvfn
but copies the text into the SV instead of appending it.
Usually used via one of its frontends "sv_vsetpvf
" and "sv_vsetpvf_mg
".
void sv_vsetpvfn(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const Size_t sv_count, bool *const maybe_tainted)
vnewSVpvf
Like "newSVpvf"
but the arguments are an encapsulated argument list.
SV* vnewSVpvf(const char *const pat, va_list *const args)
SvTAINT
Taints an SV if tainting is enabled, and if some input to the current expression is tainted--usually a variable, but possibly also implicit inputs such as locale settings. SvTAINT
propagates that taintedness to the outputs of an expression in a pessimistic fashion; i.e., without paying attention to precisely which outputs are influenced by which inputs.
void SvTAINT(SV* sv)
SvTAINTED
Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.
bool SvTAINTED(SV* sv)
SvTAINTED_off
Untaints an SV. Be very careful with this routine, as it short-circuits some of Perl's fundamental security features. XS module authors should not use this function unless they fully understand all the implications of unconditionally untainting the value. Untainting should be done in the standard perl fashion, via a carefully crafted regexp, rather than directly untainting variables.
void SvTAINTED_off(SV* sv)
ASCTIME_R_PROTO
This symbol encodes the prototype of asctime_r
. It is zero if d_asctime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_asctime_r
is defined.
CTIME_R_PROTO
This symbol encodes the prototype of ctime_r
. It is zero if d_ctime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_ctime_r
is defined.
GMTIME_MAX
This symbol contains the maximum value for the time_t
offset that the system function gmtime () accepts, and defaults to 0
GMTIME_MIN
This symbol contains the minimum value for the time_t
offset that the system function gmtime () accepts, and defaults to 0
GMTIME_R_PROTO
This symbol encodes the prototype of gmtime_r
. It is zero if d_gmtime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_gmtime_r
is defined.
HAS_ASCTIME64
This symbol, if defined, indicates that the asctime64
() routine is available to do the 64bit variant of asctime ()
HAS_ASCTIME_R
This symbol, if defined, indicates that the asctime_r
routine is available to asctime re-entrantly.
HAS_CTIME64
This symbol, if defined, indicates that the ctime64
() routine is available to do the 64bit variant of ctime ()
HAS_CTIME_R
This symbol, if defined, indicates that the ctime_r
routine is available to ctime re-entrantly.
HAS_DIFFTIME64
This symbol, if defined, indicates that the difftime64
() routine is available to do the 64bit variant of difftime ()
HAS_FUTIMES
This symbol, if defined, indicates that the futimes
routine is available to change file descriptor time stamps with struct timevals
.
HAS_GETITIMER
This symbol, if defined, indicates that the getitimer
routine is available to return interval timers.
HAS_GETTIMEOFDAY
This symbol, if defined, indicates that the gettimeofday()
system call is available for a sub-second accuracy clock. Usually, the file sys/resource.h needs to be included (see "I_SYS_RESOURCE"
). The type "Timeval" should be used to refer to "struct timeval
".
HAS_GMTIME64
This symbol, if defined, indicates that the gmtime64
() routine is available to do the 64bit variant of gmtime ()
HAS_GMTIME_R
This symbol, if defined, indicates that the gmtime_r
routine is available to gmtime re-entrantly.
HAS_LOCALTIME64
This symbol, if defined, indicates that the localtime64
() routine is available to do the 64bit variant of localtime ()
HAS_LOCALTIME_R
This symbol, if defined, indicates that the localtime_r
routine is available to localtime re-entrantly.
HAS_MKTIME64
This symbol, if defined, indicates that the mktime64
() routine is available to do the 64bit variant of mktime ()
HAS_NANOSLEEP
This symbol, if defined, indicates that the nanosleep
system call is available to sleep with 1E-9 sec accuracy.
HAS_SETITIMER
This symbol, if defined, indicates that the setitimer
routine is available to set interval timers.
HAS_STRFTIME
This symbol, if defined, indicates that the strftime
routine is available to do time formatting.
HAS_TIMEGM
This symbol, if defined, indicates that the timegm
routine is available to do the opposite of gmtime ()
HAS_TIMES
This symbol, if defined, indicates that the times()
routine exists. Note that this became obsolete on some systems (SUNOS
), which now use getrusage()
. It may be necessary to include sys/times.h.
HAS_TM_TM_GMTOFF
This symbol, if defined, indicates to the C program that the struct tm
has a tm_gmtoff
field.
HAS_TM_TM_ZONE
This symbol, if defined, indicates to the C program that the struct tm
has a tm_zone
field.
HAS_TZNAME
This symbol, if defined, indicates that the tzname[]
array is available to access timezone names.
HAS_USLEEP
This symbol, if defined, indicates that the usleep
routine is available to let the process sleep on a sub-second accuracy.
HAS_USLEEP_PROTO
This symbol, if defined, indicates that the system provides a prototype for the usleep()
function. Otherwise, it is up to the program to supply one. A good guess is
extern int usleep(useconds_t);
I_TIME
This symbol is always defined, and indicates to the C program that it should include time.h.
#ifdef I_TIME #include <time.h> #endif
I_UTIME
This symbol, if defined, indicates to the C program that it should include utime.h.
#ifdef I_UTIME #include <utime.h> #endif
LOCALTIME_MAX
This symbol contains the maximum value for the time_t
offset that the system function localtime () accepts, and defaults to 0
LOCALTIME_MIN
This symbol contains the minimum value for the time_t
offset that the system function localtime () accepts, and defaults to 0
LOCALTIME_R_NEEDS_TZSET
Many libc's localtime_r
implementations do not call tzset, making them differ from localtime()
, and making timezone changes using $ENV
{TZ} without explicitly calling tzset impossible. This symbol makes us call tzset before localtime_r
LOCALTIME_R_PROTO
This symbol encodes the prototype of localtime_r
. It is zero if d_localtime_r
is undef, and one of the REENTRANT_PROTO_T_ABC
macros of reentr.h if d_localtime_r
is defined.
mini_mktime
normalise
values without the localtime() semantics (and overhead) of mktime().struct tm
void mini_mktime(struct tm *ptm)
my_strftime
strftime(), but with a different API so that the return value is a pointer to the formatted result (which MUST be arranged to be FREED BY THE CALLER). This allows this function to increase the buffer size as needed, so that the caller doesn't have to worry about that.
Note that yday and wday effectively are ignored by this function, as mini_mktime() overwrites them
Also note that this is always executed in the underlying locale of the program, giving localized results.
NOTE: my_strftime
must be explicitly called as Perl_my_strftime
with an aTHX_
parameter.
char * Perl_my_strftime(pTHX_ const char *fmt, int sec, int min, int hour, int mday, int mon, int year, int wday, int yday, int isdst)
DB_Hash_t
This symbol contains the type of the prefix structure element in the db.h header file. In older versions of DB, it was int, while in newer ones it is size_t
.
DB_Prefix_t
This symbol contains the type of the prefix structure element in the db.h header file. In older versions of DB, it was int, while in newer ones it is u_int32_t
.
Direntry_t
This symbol is set to 'struct direct
' or 'struct dirent
' depending on whether dirent is available or not. You should use this pseudo type to portably declare your directory entries.
Fpos_t
This symbol holds the type used to declare file positions in libc. It can be fpos_t
, long, uint, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Gid_t
This symbol holds the return type of getgid()
and the type of argument to setrgid()
and related functions. Typically, it is the type of group ids in the kernel. It can be int, ushort, gid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Groups_t
This symbol holds the type used for the second argument to getgroups()
and setgroups()
. Usually, this is the same as gidtype (gid_t
) , but sometimes it isn't. It can be int, ushort, gid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information. This is only required if you have getgroups()
or setgroups()
..
Mmap_t
This symbol holds the return type of the mmap()
system call (and simultaneously the type of the first argument). Usually set to 'void *' or 'caddr_t
'.
Mode_t
This symbol holds the type used to declare file modes for systems calls. It is usually mode_t
, but may be int or unsigned short. It may be necessary to include sys/types.h to get any typedef'ed information.
Off_t
This symbol holds the type used to declare offsets in the kernel. It can be int, long, off_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Pid_t
This symbol holds the type used to declare process ids in the kernel. It can be int, uint, pid_t
, etc... It may be necessary to include sys/types.h to get any typedef'ed information.
Select_fd_set_t
This symbol holds the type used for the 2nd, 3rd, and 4th arguments to select. Usually, this is 'fd_set
*', if HAS_FD_SET
is defined, and 'int *' otherwise. This is only useful if you have select()
, of course.
Shmat_t
This symbol holds the return type of the shmat()
system call. Usually set to 'void *' or 'char *'.
Signal_t
This symbol's value is either "void" or "int", corresponding to the appropriate return type of a signal handler. Thus, you can declare a signal handler using "Signal_t
(*handler)()", and define the handler using "Signal_t
handler(sig)
".
Size_t
This symbol holds the type used to declare length parameters for string functions. It is usually size_t
, but may be unsigned long, int, etc. It may be necessary to include sys/types.h to get any typedef'ed information.
Sock_size_t
This symbol holds the type used for the size argument of various socket calls (just the base type, not the pointer-to).
SSize_t
This symbol holds the type used by functions that return a count of bytes or an error condition. It must be a signed type. It is usually ssize_t
, but may be long or int, etc. It may be necessary to include sys/types.h or unistd.h to get any typedef'ed information. We will pick a type such that sizeof(SSize_t)
== sizeof(Size_t)
.
Time_t
This symbol holds the type returned by time()
. It can be long, or time_t
on BSD
sites (in which case sys/types.h should be included).
"Unicode Support" in perlguts has an introduction to this API.
See also "Character classification"
, "Character case changing"
, and "String Handling"
. Various functions outside this section also work specially with Unicode. Search for the string "utf8" in this document.
BOM_UTF8
This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode BYTE ORDER MARK (U+FEFF) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms.
can be used to get its length in bytes.sizeof(BOM_UTF8) - 1
bytes_cmp_utf8
Compares the sequence of characters (stored as octets) in b
, blen
with the sequence of characters (stored as UTF-8) in u
, ulen
. Returns 0 if they are equal, -1 or -2 if the first string is less than the second string, +1 or +2 if the first string is greater than the second string.
-1 or +1 is returned if the shorter string was identical to the start of the longer string. -2 or +2 is returned if there was a difference between characters within the strings.
int bytes_cmp_utf8(const U8 *b, STRLEN blen, const U8 *u, STRLEN ulen)
bytes_from_utf8
NOTE: bytes_from_utf8
is experimental and may change or be removed without notice.
Converts a potentially UTF-8 encoded string s
of length *lenp
into native byte encoding. On input, the boolean *is_utf8p
gives whether or not s
is actually encoded in UTF-8.
Unlike "utf8_to_bytes" but like "bytes_to_utf8", this is non-destructive of the input string.
Do nothing if *is_utf8p
is 0, or if there are code points in the string not expressible in native byte encoding. In these cases, *is_utf8p
and *lenp
are unchanged, and the return value is the original s
.
Otherwise, *is_utf8p
is set to 0, and the return value is a pointer to a newly created string containing a downgraded copy of s
, and whose length is returned in *lenp
, updated. The new string is NUL
-terminated. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of *lenp
before the call, and subtracting the after-call value of *lenp
from it.
U8* bytes_from_utf8(const U8 *s, STRLEN *lenp, bool *is_utf8p)
bytes_to_utf8
NOTE: bytes_to_utf8
is experimental and may change or be removed without notice.
Converts a string s
of length *lenp
bytes from the native encoding into UTF-8. Returns a pointer to the newly-created string, and sets *lenp
to reflect the new length in bytes. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of *lenp
before the call, and subtracting it from the after-call value of *lenp
.
A NUL
character will be written after the end of the string.
If you want to convert to UTF-8 from encodings other than the native (Latin1 or EBCDIC), see "sv_recode_to_utf8"().
U8* bytes_to_utf8(const U8 *s, STRLEN *lenp)
DO_UTF8
Returns a bool giving whether or not the PV in sv
is to be treated as being encoded in UTF-8.
You should use this after a call to SvPV()
or one of its variants, in case any call to string overloading updates the internal UTF-8 encoding flag.
bool DO_UTF8(SV* sv)
foldEQ_utf8
Returns true if the leading portions of the strings s1
and s2
(either or both of which may be in UTF-8) are the same case-insensitively; false otherwise. How far into the strings to compare is determined by other input parameters.
If u1
is true, the string s1
is assumed to be in UTF-8-encoded Unicode; otherwise it is assumed to be in native 8-bit encoding. Correspondingly for u2
with respect to s2
.
If the byte length l1
is non-zero, it says how far into s1
to check for fold equality. In other words, s1
+l1
will be used as a goal to reach. The scan will not be considered to be a match unless the goal is reached, and scanning won't continue past that goal. Correspondingly for l2
with respect to s2
.
If pe1
is non-NULL
and the pointer it points to is not NULL
, that pointer is considered an end pointer to the position 1 byte past the maximum point in s1
beyond which scanning will not continue under any circumstances. (This routine assumes that UTF-8 encoded input strings are not malformed; malformed input can cause it to read past pe1
). This means that if both l1
and pe1
are specified, and pe1
is less than s1
+l1
, the match will never be successful because it can never get as far as its goal (and in fact is asserted against). Correspondingly for pe2
with respect to s2
.
At least one of s1
and s2
must have a goal (at least one of l1
and l2
must be non-zero), and if both do, both have to be reached for a successful match. Also, if the fold of a character is multiple characters, all of them must be matched (see tr21 reference below for 'folding').
Upon a successful match, if pe1
is non-NULL
, it will be set to point to the beginning of the next character of s1
beyond what was matched. Correspondingly for pe2
and s2
.
For case-insensitiveness, the "casefolding" of Unicode is used instead of upper/lowercasing both the characters, see https://www.unicode.org/reports/tr21/ (Case Mappings).
I32 foldEQ_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)
is_ascii_string
This is a misleadingly-named synonym for "is_utf8_invariant_string". On ASCII-ish platforms, the name isn't misleading: the ASCII-range characters are exactly the UTF-8 invariants. But EBCDIC machines have more invariants than just the ASCII characters, so is_utf8_invariant_string
is preferred.
bool is_ascii_string(const U8* const s, STRLEN len)
is_c9strict_utf8_string
Returns TRUE if the first len
bytes of string s
form a valid UTF-8-encoded string that conforms to Unicode Corrigendum #9; otherwise it returns FALSE. If len
is 0, it will be calculated using strlen(s)
(which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
This function returns FALSE for strings containing any code points above the Unicode max of 0x10FFFF or surrogate code points, but accepts non-character code points per Corrigendum #9.
See also "is_utf8_invariant_string"
, "is_utf8_invariant_string_loc"
, "is_utf8_string"
, "is_utf8_string_flags"
, "is_utf8_string_loc"
, "is_utf8_string_loc_flags"
, "is_utf8_string_loclen"
, "is_utf8_string_loclen_flags"
, "is_utf8_fixed_width_buf_flags"
, "is_utf8_fixed_width_buf_loc_flags"
, "is_utf8_fixed_width_buf_loclen_flags"
, "is_strict_utf8_string"
, "is_strict_utf8_string_loc"
, "is_strict_utf8_string_loclen"
, "is_c9strict_utf8_string_loc"
, and "is_c9strict_utf8_string_loclen"
.
bool is_c9strict_utf8_string(const U8 *s, STRLEN len)
is_c9strict_utf8_string_loc
Like "is_c9strict_utf8_string"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer.
See also "is_c9strict_utf8_string_loclen"
.
bool is_c9strict_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)
is_c9strict_utf8_string_loclen
Like "is_c9strict_utf8_string"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer, and the number of UTF-8 encoded characters in the el
pointer.
See also "is_c9strict_utf8_string_loc"
.
bool is_c9strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
isC9_STRICT_UTF8_CHAR
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8 that represents some Unicode non-surrogate code point; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at e - 1
s
comprise the code point's representation. Any bytes remaining before e
, but beyond the ones needed to form the first code point in s
, are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF. This differs from "isSTRICT_UTF8_CHAR"
only in that it accepts non-character code points. This corresponds to Unicode Corrigendum #9. which said that non-character code points are merely discouraged rather than completely forbidden in open interchange. See "Noncharacter code points" in perlunicode.
Use "isUTF8_CHAR"
to check for Perl's extended UTF-8; and "isUTF8_CHAR_flags"
for a more customized definition.
Use "is_c9strict_utf8_string"
, "is_c9strict_utf8_string_loc"
, and "is_c9strict_utf8_string_loclen"
to check entire strings.
Size_t isC9_STRICT_UTF8_CHAR(const U8 * const s0, const U8 * const e)
is_invariant_string
This is a somewhat misleadingly-named synonym for "is_utf8_invariant_string". is_utf8_invariant_string
is preferred, as it indicates under what conditions the string is invariant.
bool is_invariant_string(const U8* const s, STRLEN len)
isSTRICT_UTF8_CHAR
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8 that represents some Unicode code point completely acceptable for open interchange between all applications; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at e - 1
s
comprise the code point's representation. Any bytes remaining before e
, but beyond the ones needed to form the first code point in s
, are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF, and must not be a surrogate nor a non-character code point. Thus this excludes any code point from Perl's extended UTF-8.
This is used to efficiently decide if the next few bytes in s
is legal Unicode-acceptable UTF-8 for a single character.
Use "isC9_STRICT_UTF8_CHAR"
to use the Unicode Corrigendum #9 definition of allowable code points; "isUTF8_CHAR"
to check for Perl's extended UTF-8; and "isUTF8_CHAR_flags"
for a more customized definition.
Use "is_strict_utf8_string"
, "is_strict_utf8_string_loc"
, and "is_strict_utf8_string_loclen"
to check entire strings.
Size_t isSTRICT_UTF8_CHAR(const U8 * const s0, const U8 * const e)
is_strict_utf8_string
Returns TRUE if the first len
bytes of string s
form a valid UTF-8-encoded string that is fully interchangeable by any application using Unicode rules; otherwise it returns FALSE. If len
is 0, it will be calculated using strlen(s)
(which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
This function returns FALSE for strings containing any code points above the Unicode max of 0x10FFFF, surrogate code points, or non-character code points.
See also "is_utf8_invariant_string"
, "is_utf8_invariant_string_loc"
, "is_utf8_string"
, "is_utf8_string_flags"
, "is_utf8_string_loc"
, "is_utf8_string_loc_flags"
, "is_utf8_string_loclen"
, "is_utf8_string_loclen_flags"
, "is_utf8_fixed_width_buf_flags"
, "is_utf8_fixed_width_buf_loc_flags"
, "is_utf8_fixed_width_buf_loclen_flags"
, "is_strict_utf8_string_loc"
, "is_strict_utf8_string_loclen"
, "is_c9strict_utf8_string"
, "is_c9strict_utf8_string_loc"
, and "is_c9strict_utf8_string_loclen"
.
bool is_strict_utf8_string(const U8 *s, STRLEN len)
is_strict_utf8_string_loc
Like "is_strict_utf8_string"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer.
See also "is_strict_utf8_string_loclen"
.
bool is_strict_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)
is_strict_utf8_string_loclen
Like "is_strict_utf8_string"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer, and the number of UTF-8 encoded characters in the el
pointer.
See also "is_strict_utf8_string_loc"
.
bool is_strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
is_utf8_char
DEPRECATED!
It is planned to remove is_utf8_char
from a future release of Perl. Do not use it for new code; remove it from existing code.
Tests if some arbitrary number of bytes begins in a valid UTF-8 character. Note that an INVARIANT (i.e. ASCII on non-EBCDIC machines) character is a valid UTF-8 character. The actual number of bytes in the UTF-8 character will be returned if it is valid, otherwise 0.
This function is deprecated due to the possibility that malformed input could cause reading beyond the end of the input buffer. Use "isUTF8_CHAR" instead.
STRLEN is_utf8_char(const U8 *s)
is_utf8_char_buf
This is identical to the macro "isUTF8_CHAR" in perlapi.
STRLEN is_utf8_char_buf(const U8 *buf, const U8 *buf_end)
is_utf8_fixed_width_buf_flags
Returns TRUE if the fixed-width buffer starting at s
with length len
is entirely valid UTF-8, subject to the restrictions given by flags
; otherwise it returns FALSE.
If flags
is 0, any well-formed UTF-8, as extended by Perl, is accepted without restriction. If the final few bytes of the buffer do not form a complete code point, this will return TRUE anyway, provided that "is_utf8_valid_partial_char_flags"
returns TRUE for them.
If flags
in non-zero, it can be any combination of the UTF8_DISALLOW_foo
flags accepted by "utf8n_to_uvchr"
, and with the same meanings.
This function differs from "is_utf8_string_flags"
only in that the latter returns FALSE if the final few bytes of the string don't form a complete code point.
bool is_utf8_fixed_width_buf_flags(const U8 * const s, STRLEN len, const U32 flags)
is_utf8_fixed_width_buf_loclen_flags
Like "is_utf8_fixed_width_buf_loc_flags"
but stores the number of complete, valid characters found in the el
pointer.
bool is_utf8_fixed_width_buf_loclen_flags(const U8 * const s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)
is_utf8_fixed_width_buf_loc_flags
Like "is_utf8_fixed_width_buf_flags"
but stores the location of the failure in the ep
pointer. If the function returns TRUE, *ep
will point to the beginning of any partial character at the end of the buffer; if there is no partial character *ep
will contain s
+len
.
See also "is_utf8_fixed_width_buf_loclen_flags"
.
bool is_utf8_fixed_width_buf_loc_flags(const U8 * const s, STRLEN len, const U8 **ep, const U32 flags)
is_utf8_invariant_string
Returns TRUE if the first len
bytes of the string s
are the same regardless of the UTF-8 encoding of the string (or UTF-EBCDIC encoding on EBCDIC machines); otherwise it returns FALSE. That is, it returns TRUE if they are UTF-8 invariant. On ASCII-ish machines, all the ASCII characters and only the ASCII characters fit this definition. On EBCDIC machines, the ASCII-range characters are invariant, but so also are the C1 controls.
If len
is 0, it will be calculated using strlen(s)
, (which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte).
See also "is_utf8_string"
, "is_utf8_string_flags"
, "is_utf8_string_loc"
, "is_utf8_string_loc_flags"
, "is_utf8_string_loclen"
, "is_utf8_string_loclen_flags"
, "is_utf8_fixed_width_buf_flags"
, "is_utf8_fixed_width_buf_loc_flags"
, "is_utf8_fixed_width_buf_loclen_flags"
, "is_strict_utf8_string"
, "is_strict_utf8_string_loc"
, "is_strict_utf8_string_loclen"
, "is_c9strict_utf8_string"
, "is_c9strict_utf8_string_loc"
, and "is_c9strict_utf8_string_loclen"
.
bool is_utf8_invariant_string(const U8* const s, STRLEN len)
is_utf8_invariant_string_loc
Like "is_utf8_invariant_string"
but upon failure, stores the location of the first UTF-8 variant character in the ep
pointer; if all characters are UTF-8 invariant, this function does not change the contents of *ep
.
bool is_utf8_invariant_string_loc(const U8* const s, STRLEN len, const U8 ** ep)
is_utf8_string
Returns TRUE if the first len
bytes of string s
form a valid Perl-extended-UTF-8 string; returns FALSE otherwise. If len
is 0, it will be calculated using strlen(s)
(which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
This function considers Perl's extended UTF-8 to be valid. That means that code points above Unicode, surrogates, and non-character code points are considered valid by this function. Use "is_strict_utf8_string"
, "is_c9strict_utf8_string"
, or "is_utf8_string_flags"
to restrict what code points are considered valid.
See also "is_utf8_invariant_string"
, "is_utf8_invariant_string_loc"
, "is_utf8_string_loc"
, "is_utf8_string_loclen"
, "is_utf8_fixed_width_buf_flags"
, "is_utf8_fixed_width_buf_loc_flags"
, "is_utf8_fixed_width_buf_loclen_flags"
,
bool is_utf8_string(const U8 *s, STRLEN len)
is_utf8_string_flags
Returns TRUE if the first len
bytes of string s
form a valid UTF-8 string, subject to the restrictions imposed by flags
; returns FALSE otherwise. If len
is 0, it will be calculated using strlen(s)
(which means if you use this option, that s
can't have embedded NUL
characters and has to have a terminating NUL
byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
If flags
is 0, this gives the same results as "is_utf8_string"
; if flags
is UTF8_DISALLOW_ILLEGAL_INTERCHANGE
, this gives the same results as "is_strict_utf8_string"
; and if flags
is UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE
, this gives the same results as "is_c9strict_utf8_string"
. Otherwise flags
may be any combination of the UTF8_DISALLOW_foo
flags understood by "utf8n_to_uvchr"
, with the same meanings.
See also "is_utf8_invariant_string"
, "is_utf8_invariant_string_loc"
, "is_utf8_string"
, "is_utf8_string_loc"
, "is_utf8_string_loc_flags"
, "is_utf8_string_loclen"
, "is_utf8_string_loclen_flags"
, "is_utf8_fixed_width_buf_flags"
, "is_utf8_fixed_width_buf_loc_flags"
, "is_utf8_fixed_width_buf_loclen_flags"
, "is_strict_utf8_string"
, "is_strict_utf8_string_loc"
, "is_strict_utf8_string_loclen"
, "is_c9strict_utf8_string"
, "is_c9strict_utf8_string_loc"
, and "is_c9strict_utf8_string_loclen"
.
bool is_utf8_string_flags(const U8 *s, STRLEN len, const U32 flags)
is_utf8_string_loc
Like "is_utf8_string"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer.
See also "is_utf8_string_loclen"
.
bool is_utf8_string_loc(const U8 *s, const STRLEN len, const U8 **ep)
is_utf8_string_loclen
Like "is_utf8_string"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer, and the number of UTF-8 encoded characters in the el
pointer.
See also "is_utf8_string_loc"
.
bool is_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
is_utf8_string_loclen_flags
Like "is_utf8_string_flags"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer, and the number of UTF-8 encoded characters in the el
pointer.
See also "is_utf8_string_loc_flags"
.
bool is_utf8_string_loclen_flags(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)
is_utf8_string_loc_flags
Like "is_utf8_string_flags"
but stores the location of the failure (in the case of "utf8ness failure") or the location s
+len
(in the case of "utf8ness success") in the ep
pointer.
See also "is_utf8_string_loclen_flags"
.
bool is_utf8_string_loc_flags(const U8 *s, STRLEN len, const U8 **ep, const U32 flags)
is_utf8_valid_partial_char
Returns 0 if the sequence of bytes starting at s
and looking no further than
is the UTF-8 encoding, as extended by Perl, for one or more code points. Otherwise, it returns 1 if there exists at least one non-empty sequence of bytes that when appended to sequence e - 1
s
, starting at position e
causes the entire sequence to be the well-formed UTF-8 of some code point; otherwise returns 0.
In other words this returns TRUE if s
points to a partial UTF-8-encoded code point.
This is useful when a fixed-length buffer is being tested for being well-formed UTF-8, but the final few bytes in it don't comprise a full character; that is, it is split somewhere in the middle of the final code point's UTF-8 representation. (Presumably when the buffer is refreshed with the next chunk of data, the new first bytes will complete the partial code point.) This function is used to verify that the final bytes in the current buffer are in fact the legal beginning of some code point, so that if they aren't, the failure can be signalled without having to wait for the next read.
bool is_utf8_valid_partial_char(const U8 * const s0, const U8 * const e)
is_utf8_valid_partial_char_flags
Like "is_utf8_valid_partial_char"
, it returns a boolean giving whether or not the input is a valid UTF-8 encoded partial character, but it takes an extra parameter, flags
, which can further restrict which code points are considered valid.
If flags
is 0, this behaves identically to "is_utf8_valid_partial_char"
. Otherwise flags
can be any combination of the UTF8_DISALLOW_foo
flags accepted by "utf8n_to_uvchr"
. If there is any sequence of bytes that can complete the input partial character in such a way that a non-prohibited character is formed, the function returns TRUE; otherwise FALSE. Non character code points cannot be determined based on partial character input. But many of the other possible excluded types can be determined from just the first one or two bytes.
bool is_utf8_valid_partial_char_flags(const U8 * const s0, const U8 * const e, const U32 flags)
isUTF8_CHAR
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8, as extended by Perl, that represents some code point; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at e - 1
s
comprise the code point's representation. Any bytes remaining before e
, but beyond the ones needed to form the first code point in s
, are not examined.
The code point can be any that will fit in an IV on this machine, using Perl's extension to official UTF-8 to represent those higher than the Unicode maximum of 0x10FFFF. That means that this macro is used to efficiently decide if the next few bytes in s
is legal UTF-8 for a single character.
Use "isSTRICT_UTF8_CHAR"
to restrict the acceptable code points to those defined by Unicode to be fully interchangeable across applications; "isC9_STRICT_UTF8_CHAR"
to use the Unicode Corrigendum #9 definition of allowable code points; and "isUTF8_CHAR_flags"
for a more customized definition.
Use "is_utf8_string"
, "is_utf8_string_loc"
, and "is_utf8_string_loclen"
to check entire strings.
Note also that a UTF-8 "invariant" character (i.e. ASCII on non-EBCDIC machines) is a valid UTF-8 character.
Size_t isUTF8_CHAR(const U8 * const s0, const U8 * const e)
isUTF8_CHAR_flags
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8, as extended by Perl, that represents some code point, subject to the restrictions given by e - 1
flags
; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at s
comprise the code point's representation. Any bytes remaining before e
, but beyond the ones needed to form the first code point in s
, are not examined.
If flags
is 0, this gives the same results as "isUTF8_CHAR"
; if flags
is UTF8_DISALLOW_ILLEGAL_INTERCHANGE
, this gives the same results as "isSTRICT_UTF8_CHAR"
; and if flags
is UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE
, this gives the same results as "isC9_STRICT_UTF8_CHAR"
. Otherwise flags
may be any combination of the UTF8_DISALLOW_foo
flags understood by "utf8n_to_uvchr"
, with the same meanings.
The three alternative macros are for the most commonly needed validations; they are likely to run somewhat faster than this more general one, as they can be inlined into your code.
Use "is_utf8_string_flags", "is_utf8_string_loc_flags", and "is_utf8_string_loclen_flags" to check entire strings.
Size_t isUTF8_CHAR_flags(const U8 * const s0, const U8 * const e, const U32 flags)
LATIN1_TO_NATIVE
Returns the native equivalent of the input Latin-1 code point (including ASCII and control characters) given by ch
. Thus, LATIN1_TO_NATIVE(66)
on EBCDIC platforms returns 194. These each represent the character "B"
on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
For conversion of code points potentially larger than will fit in a character, use "UNI_TO_NATIVE".
U8 LATIN1_TO_NATIVE(U8 ch)
NATIVE_TO_LATIN1
Returns the Latin-1 (including ASCII and control characters) equivalent of the input native code point given by ch
. Thus, NATIVE_TO_LATIN1(193)
on EBCDIC platforms returns 65. These each represent the character "A"
on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
For conversion of code points potentially larger than will fit in a character, use "NATIVE_TO_UNI".
U8 NATIVE_TO_LATIN1(U8 ch)
NATIVE_TO_UNI
Returns the Unicode equivalent of the input native code point given by ch
. Thus, NATIVE_TO_UNI(195)
on EBCDIC platforms returns 67. These each represent the character "C"
on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
UV NATIVE_TO_UNI(UV ch)
pv_uni_display
Build to the scalar dsv
a displayable version of the UTF-8 encoded string spv
, length len
, the displayable version being at most pvlim
bytes long (if longer, the rest is truncated and "..."
will be appended).
The flags
argument can have UNI_DISPLAY_ISPRINT
set to display isPRINT()
able characters as themselves, UNI_DISPLAY_BACKSLASH
to display the \\[nrfta\\]
as the backslashed versions (like "\n"
) (UNI_DISPLAY_BACKSLASH
is preferred over UNI_DISPLAY_ISPRINT
for "\\"
). UNI_DISPLAY_QQ
(and its alias UNI_DISPLAY_REGEX
) have both UNI_DISPLAY_BACKSLASH
and UNI_DISPLAY_ISPRINT
turned on.
Additionally, there is now UNI_DISPLAY_BACKSPACE
which allows \b
for a backspace, but only when UNI_DISPLAY_BACKSLASH
also is set.
The pointer to the PV of the dsv
is returned.
See also "sv_uni_display".
char* pv_uni_display(SV *dsv, const U8 *spv, STRLEN len, STRLEN pvlim, UV flags)
REPLACEMENT_CHARACTER_UTF8
This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode REPLACEMENT CHARACTER (U+FFFD) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms.
can be used to get its length in bytes.sizeof(REPLACEMENT_CHARACTER_UTF8) - 1
sv_cat_decode
encoding
is assumed to be an Encode
object, the PV of ssv
is assumed to be octets in that encoding and decoding the input starts from the position which
pointed to. (PV + *offset)
dsv
will be concatenated with the decoded UTF-8 string from ssv
. Decoding will terminate when the string tstr
appears in decoding output or the input ends on the PV of ssv
. The value which offset
points will be modified to the last input position on ssv
.
Returns TRUE if the terminator was found, else returns FALSE.
bool sv_cat_decode(SV* dsv, SV *encoding, SV *ssv, int *offset, char* tstr, int tlen)
sv_recode_to_utf8
encoding
is assumed to be an Encode
object, on entry the PV of sv
is assumed to be octets in that encoding, and sv
will be converted into Unicode (and UTF-8).
If sv
already is UTF-8 (or if it is not POK
), or if encoding
is not a reference, nothing is done to sv
. If encoding
is not an Encode::XS
Encoding object, bad things will happen. (See encoding and Encode.)
The PV of sv
is returned.
char* sv_recode_to_utf8(SV* sv, SV *encoding)
sv_uni_display
Build to the scalar dsv
a displayable version of the scalar sv
, the displayable version being at most pvlim
bytes long (if longer, the rest is truncated and "..." will be appended).
The flags
argument is as in "pv_uni_display"().
The pointer to the PV of the dsv
is returned.
char* sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim, UV flags)
UNICODE_IS_NONCHAR
Returns a boolean as to whether or not uv
is one of the Unicode non-character code points
bool UNICODE_IS_NONCHAR(const UV uv)
UNICODE_IS_REPLACEMENT
Returns a boolean as to whether or not uv
is the Unicode REPLACEMENT CHARACTER
bool UNICODE_IS_REPLACEMENT(const UV uv)
UNICODE_IS_SUPER
Returns a boolean as to whether or not uv
is above the maximum legal Unicode code point of U+10FFFF.
bool UNICODE_IS_SUPER(const UV uv)
UNICODE_IS_SURROGATE
Returns a boolean as to whether or not uv
is one of the Unicode surrogate code points
bool UNICODE_IS_SURROGATE(const UV uv)
UNI_TO_NATIVE
Returns the native equivalent of the input Unicode code point given by ch
. Thus, UNI_TO_NATIVE(68)
on EBCDIC platforms returns 196. These each represent the character "D"
on their respective platforms. On ASCII platforms no conversion is needed, so this macro expands to just its input, adding no time nor space requirements to the implementation.
UV UNI_TO_NATIVE(UV ch)
utf8n_to_uvchr
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use "utf8_to_uvchr_buf"() rather than call this directly.
Bottom level UTF-8 decode routine. Returns the native code point value of the first character in the string s
, which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer than curlen
bytes; *retlen
(if retlen
isn't NULL) will be set to the length, in bytes, of that character.
The value of flags
determines the behavior when s
does not point to a well-formed UTF-8 character. If flags
is 0, encountering a malformation causes zero to be returned and *retlen
is set so that (
) is the next possible position in s
+ *retlen
s
that could begin a non-malformed character. Also, if UTF-8 warnings haven't been lexically disabled, a warning is raised. Some UTF-8 input sequences may contain multiple malformations. This function tries to find every possible one in each call, so multiple warnings can be raised for the same sequence.
Various ALLOW flags can be set in flags
to allow (and not warn on) individual types of malformations, such as the sequence being overlong (that is, when there is a shorter sequence that can express the same code point; overlong sequences are expressly forbidden in the UTF-8 standard due to potential security issues). Another malformation example is the first byte of a character not being a legal first byte. See utf8.h for the list of such flags. Even if allowed, this function generally returns the Unicode REPLACEMENT CHARACTER when it encounters a malformation. There are flags in utf8.h to override this behavior for the overlong malformations, but don't do that except for very specialized purposes.
The UTF8_CHECK_ONLY
flag overrides the behavior when a non-allowed (by other flags) malformation is found. If this flag is set, the routine assumes that the caller will raise a warning, and this function will silently just set retlen
to -1
(cast to STRLEN
) and return zero.
Note that this API requires disambiguation between successful decoding a NUL
character, and an error return (unless the UTF8_CHECK_ONLY
flag is set), as in both cases, 0 is returned, and, depending on the malformation, retlen
may be set to 1. To disambiguate, upon a zero return, see if the first byte of s
is 0 as well. If so, the input was a NUL
; if not, the input had an error. Or you can use "utf8n_to_uvchr_error"
.
Certain code points are considered problematic. These are Unicode surrogates, Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF. By default these are considered regular code points, but certain situations warrant special handling for them, which can be specified using the flags
parameter. If flags
contains UTF8_DISALLOW_ILLEGAL_INTERCHANGE
, all three classes are treated as malformations and handled as such. The flags UTF8_DISALLOW_SURROGATE
, UTF8_DISALLOW_NONCHAR
, and UTF8_DISALLOW_SUPER
(meaning above the legal Unicode maximum) can be set to disallow these categories individually. UTF8_DISALLOW_ILLEGAL_INTERCHANGE
restricts the allowed inputs to the strict UTF-8 traditionally defined by Unicode. Use UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE
to use the strictness definition given by Unicode Corrigendum #9. The difference between traditional strictness and C9 strictness is that the latter does not forbid non-character code points. (They are still discouraged, however.) For more discussion see "Noncharacter code points" in perlunicode.
The flags UTF8_WARN_ILLEGAL_INTERCHANGE
, UTF8_WARN_ILLEGAL_C9_INTERCHANGE
, UTF8_WARN_SURROGATE
, UTF8_WARN_NONCHAR
, and UTF8_WARN_SUPER
will cause warning messages to be raised for their respective categories, but otherwise the code points are considered valid (not malformations). To get a category to both be treated as a malformation and raise a warning, specify both the WARN and DISALLOW flags. (But note that warnings are not raised if lexically disabled nor if UTF8_CHECK_ONLY
is also specified.)
Extremely high code points were never specified in any standard, and require an extension to UTF-8 to express, which Perl does. It is likely that programs written in something other than Perl would not be able to read files that contain these; nor would Perl understand files written by something that uses a different extension. For these reasons, there is a separate set of flags that can warn and/or disallow these extremely high code points, even if other above-Unicode ones are accepted. They are the UTF8_WARN_PERL_EXTENDED
and UTF8_DISALLOW_PERL_EXTENDED
flags. For more information see "UTF8_GOT_PERL_EXTENDED"
. Of course UTF8_DISALLOW_SUPER
will treat all above-Unicode code points, including these, as malformations. (Note that the Unicode standard considers anything above 0x10FFFF to be illegal, but there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym for UTF8_WARN_PERL_EXTENDED
is retained for backward compatibility: UTF8_WARN_ABOVE_31_BIT
. Similarly, UTF8_DISALLOW_ABOVE_31_BIT
is usable instead of the more accurately named UTF8_DISALLOW_PERL_EXTENDED
. The names are misleading because these flags can apply to code points that actually do fit in 31 bits. This happens on EBCDIC platforms, and sometimes when the overlong malformation is also present. The new names accurately describe the situation in all cases.
All other code points corresponding to Unicode characters, including private use and those yet to be assigned, are never considered malformed and never warn.
UV utf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags)
utf8n_to_uvchr_error
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use "utf8_to_uvchr_buf"() rather than call this directly.
This function is for code that needs to know what the precise malformation(s) are when an error is found. If you also need to know the generated warning messages, use "utf8n_to_uvchr_msgs"() instead.
It is like "utf8n_to_uvchr"
but it takes an extra parameter placed after all the others, errors
. If this parameter is 0, this function behaves identically to "utf8n_to_uvchr"
. Otherwise, errors
should be a pointer to a U32
variable, which this function sets to indicate any errors found. Upon return, if *errors
is 0, there were no errors found. Otherwise, *errors
is the bit-wise OR
of the bits described in the list below. Some of these bits will be set if a malformation is found, even if the input flags
parameter indicates that the given malformation is allowed; those exceptions are noted:
UTF8_GOT_PERL_EXTENDED
The input sequence is not standard UTF-8, but a Perl extension. This bit is set only if the input flags
parameter contains either the UTF8_DISALLOW_PERL_EXTENDED
or the UTF8_WARN_PERL_EXTENDED
flags.
Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard, and so some extension must be used to express them. Perl uses a natural extension to UTF-8 to represent the ones up to 2**36-1, and invented a further extension to represent even higher ones, so that any code point that fits in a 64-bit word can be represented. Text using these extensions is not likely to be portable to non-Perl code. We lump both of these extensions together and refer to them as Perl extended UTF-8. There exist other extensions that people have invented, incompatible with Perl's.
On EBCDIC platforms starting in Perl v5.24, the Perl extension for representing extremely high code points kicks in at 0x3FFF_FFFF (2**30 -1), which is lower than on ASCII. Prior to that, code points 2**31 and higher were simply unrepresentable, and a different, incompatible method was used to represent code points between 2**30 and 2**31 - 1.
On both platforms, ASCII and EBCDIC, UTF8_GOT_PERL_EXTENDED
is set if Perl extended UTF-8 is used.
In earlier Perls, this bit was named UTF8_GOT_ABOVE_31_BIT
, which you still may use for backward compatibility. That name is misleading, as this flag may be set when the code point actually does fit in 31 bits. This happens on EBCDIC platforms, and sometimes when the overlong malformation is also present. The new name accurately describes the situation in all cases.
UTF8_GOT_CONTINUATION
The input sequence was malformed in that the first byte was a UTF-8 continuation byte.
UTF8_GOT_EMPTY
The input curlen
parameter was 0.
UTF8_GOT_LONG
The input sequence was malformed in that there is some other sequence that evaluates to the same code point, but that sequence is shorter than this one.
Until Unicode 3.1, it was legal for programs to accept this malformation, but it was discovered that this created security issues.
UTF8_GOT_NONCHAR
The code point represented by the input UTF-8 sequence is for a Unicode non-character code point. This bit is set only if the input flags
parameter contains either the UTF8_DISALLOW_NONCHAR
or the UTF8_WARN_NONCHAR
flags.
UTF8_GOT_NON_CONTINUATION
The input sequence was malformed in that a non-continuation type byte was found in a position where only a continuation type one should be. See also "UTF8_GOT_SHORT"
.
UTF8_GOT_OVERFLOW
The input sequence was malformed in that it is for a code point that is not representable in the number of bits available in an IV on the current platform.
UTF8_GOT_SHORT
The input sequence was malformed in that curlen
is smaller than required for a complete sequence. In other words, the input is for a partial character sequence.
UTF8_GOT_SHORT
and UTF8_GOT_NON_CONTINUATION
both indicate a too short sequence. The difference is that UTF8_GOT_NON_CONTINUATION
indicates always that there is an error, while UTF8_GOT_SHORT
means that an incomplete sequence was looked at. If no other flags are present, it means that the sequence was valid as far as it went. Depending on the application, this could mean one of three things:
curlen
length parameter passed in was too small, and the function was prevented from examining all the necessary bytes.UTF8_GOT_SUPER
The input sequence was malformed in that it is for a non-Unicode code point; that is, one above the legal Unicode maximum. This bit is set only if the input flags
parameter contains either the UTF8_DISALLOW_SUPER
or the UTF8_WARN_SUPER
flags.
UTF8_GOT_SURROGATE
The input sequence was malformed in that it is for a -Unicode UTF-16 surrogate code point. This bit is set only if the input flags
parameter contains either the UTF8_DISALLOW_SURROGATE
or the UTF8_WARN_SURROGATE
flags.
To do your own error handling, call this function with the UTF8_CHECK_ONLY
flag to suppress any warnings, and then examine the *errors
return.
UV utf8n_to_uvchr_error(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags, U32 * errors)
utf8n_to_uvchr_msgs
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use "utf8_to_uvchr_buf"() rather than call this directly.
This function is for code that needs to know what the precise malformation(s) are when an error is found, and wants the corresponding warning and/or error messages to be returned to the caller rather than be displayed. All messages that would have been displayed if all lexical warnings are enabled will be returned.
It is just like "utf8n_to_uvchr_error"
but it takes an extra parameter placed after all the others, msgs
. If this parameter is 0, this function behaves identically to "utf8n_to_uvchr_error"
. Otherwise, msgs
should be a pointer to an AV *
variable, in which this function creates a new AV to contain any appropriate messages. The elements of the array are ordered so that the first message that would have been displayed is in the 0th element, and so on. Each element is a hash with three key-value pairs, as follows:
text
The text of the message as a SVpv
.
warn_categories
The warning category (or categories) packed into a SVuv
.
flag
A single flag bit associated with this message, in a SVuv
. The bit corresponds to some bit in the *errors
return value, such as UTF8_GOT_LONG
.
It's important to note that specifying this parameter as non-null will cause any warnings this function would otherwise generate to be suppressed, and instead be placed in *msgs
. The caller can check the lexical warnings state (or not) when choosing what to do with the returned messages.
If the flag UTF8_CHECK_ONLY
is passed, no warnings are generated, and hence no AV is created.
The caller, of course, is responsible for freeing any returned AV.
UV utf8n_to_uvchr_msgs(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags, U32 * errors, AV ** msgs)
UTF8SKIP
returns the number of bytes a non-malformed UTF-8 encoded character whose first (perhaps only) byte is pointed to by s
.
If there is a possibility of malformed input, use instead:
"UTF8_SAFE_SKIP"
if you know the maximum ending pointer in the buffer pointed to by s
; or"UTF8_CHK_SKIP"
if you don't know it.
It is better to restructure your code so the end pointer is passed down so that you know what it actually is at the point of this call, but if that isn't possible, "UTF8_CHK_SKIP"
can minimize the chance of accessing beyond the end of the input buffer.
STRLEN UTF8SKIP(char* s)
UTF8_CHK_SKIP
This is a safer version of "UTF8SKIP"
, but still not as safe as "UTF8_SAFE_SKIP"
. This version doesn't blindly assume that the input string pointed to by s
is well-formed, but verifies that there isn't a NUL terminating character before the expected end of the next character in s
. The length UTF8_CHK_SKIP
returns stops just before any such NUL.
Perl tends to add NULs, as an insurance policy, after the end of strings in SV's, so it is likely that using this macro will prevent inadvertent reading beyond the end of the input buffer, even if it is malformed UTF-8.
This macro is intended to be used by XS modules where the inputs could be malformed, and it isn't feasible to restructure to use the safer "UTF8_SAFE_SKIP"
, for example when interfacing with a C library.
STRLEN UTF8_CHK_SKIP(char* s)
utf8_distance
Returns the number of UTF-8 characters between the UTF-8 pointers a
and b
.
WARNING: use only if you *know* that the pointers point inside the same UTF-8 buffer.
IV utf8_distance(const U8 *a, const U8 *b)
utf8_hop
Return the UTF-8 pointer s
displaced by off
characters, either forward or backward.
WARNING: do not use the following unless you *know* off
is within the UTF-8 data pointed to by s
*and* that on entry s
is aligned on the first byte of character or just after the last byte of a character.
U8* utf8_hop(const U8 *s, SSize_t off)
utf8_hop_back
Return the UTF-8 pointer s
displaced by up to off
characters, backward.
off
must be non-positive.
s
must be after or equal to start
.
When moving backward it will not move before start
.
Will not exceed this limit even if the string is not valid "UTF-8".
U8* utf8_hop_back(const U8 *s, SSize_t off, const U8 *start)
utf8_hop_forward
Return the UTF-8 pointer s
displaced by up to off
characters, forward.
off
must be non-negative.
s
must be before or equal to end
.
When moving forward it will not move beyond end
.
Will not exceed this limit even if the string is not valid "UTF-8".
U8* utf8_hop_forward(const U8 *s, SSize_t off, const U8 *end)
utf8_hop_safe
Return the UTF-8 pointer s
displaced by up to off
characters, either forward or backward.
When moving backward it will not move before start
.
When moving forward it will not move beyond end
.
Will not exceed those limits even if the string is not valid "UTF-8".
U8* utf8_hop_safe(const U8 *s, SSize_t off, const U8 *start, const U8 *end)
UTF8_IS_INVARIANT
Evaluates to 1 if the byte c
represents the same character when encoded in UTF-8 as when not; otherwise evaluates to 0. UTF-8 invariant characters can be copied as-is when converting to/from UTF-8, saving time.
In spite of the name, this macro gives the correct result if the input string from which c
comes is not encoded in UTF-8.
See "UVCHR_IS_INVARIANT"
for checking if a UV is invariant.
bool UTF8_IS_INVARIANT(char c)
UTF8_IS_NONCHAR
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8 that represents one of the Unicode non-character code points; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at e - 1
s
comprise the code point's representation.
bool UTF8_IS_NONCHAR(const U8 *s, const U8 *e)
UTF8_IS_REPLACEMENT
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8 that represents the Unicode REPLACEMENT CHARACTER; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at e - 1
s
comprise the code point's representation.
bool UTF8_IS_REPLACEMENT(const U8 *s, const U8 *e)
UTF8_IS_SUPER
Recall that Perl recognizes an extension to UTF-8 that can encode code points larger than the ones defined by Unicode, which are 0..0x10FFFF.
This macro evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are from this UTF-8 extension; otherwise it evaluates to 0. If non-zero, the return is how many bytes starting at e - 1
s
comprise the code point's representation.
0 is returned if the bytes are not well-formed extended UTF-8, or if they represent a code point that cannot fit in a UV on the current platform. Hence this macro can give different results when run on a 64-bit word machine than on one with a 32-bit word size.
Note that it is illegal in Perl to have code points that are larger than what can fit in an IV on the current machine; and illegal in Unicode to have any that this macro matches
bool UTF8_IS_SUPER(const U8 *s, const U8 *e)
UTF8_IS_SURROGATE
Evaluates to non-zero if the first few bytes of the string starting at s
and looking no further than
are well-formed UTF-8 that represents one of the Unicode surrogate code points; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting at e - 1
s
comprise the code point's representation.
bool UTF8_IS_SURROGATE(const U8 *s, const U8 *e)
utf8_length
Returns the number of characters in the sequence of UTF-8-encoded bytes starting at s
and ending at the byte just before e
. If <s> and <e> point to the same place, it returns 0 with no warning raised.
If e < s
or if the scan would end up past e
, it raises a UTF8 warning and returns the number of valid characters.
STRLEN utf8_length(const U8* s, const U8 *e)
UTF8_MAXBYTES
The maximum width of a single UTF-8 encoded character, in bytes.
NOTE: Strictly speaking Perl's UTF-8 should not be called UTF-8 since UTF-8 is an encoding of Unicode, and Unicode's upper limit, 0x10FFFF, can be expressed with 4 bytes. However, Perl thinks of UTF-8 as a way to encode non-negative integers in a binary format, even those above Unicode.
UTF8_MAXBYTES_CASE
The maximum number of UTF-8 bytes a single Unicode character can uppercase/lowercase/titlecase/fold into.
UTF8_SAFE_SKIP
returns 0 if
; otherwise returns the number of bytes in the UTF-8 encoded character whose first byte is pointed to by s >= e
s
. But it never returns beyond e
. On DEBUGGING builds, it asserts that
.s <= e
STRLEN UTF8_SAFE_SKIP(char* s, char* e)
UTF8_SKIP
This is a synonym for "UTF8SKIP"
STRLEN UTF8_SKIP(char* s)
utf8_to_bytes
NOTE: utf8_to_bytes
is experimental and may change or be removed without notice.
Converts a string "s"
of length *lenp
from UTF-8 into native byte encoding. Unlike "bytes_to_utf8", this over-writes the original string, and updates *lenp
to contain the new length. Returns zero on failure (leaving "s"
unchanged) setting *lenp
to -1.
Upon successful return, the number of variants in the string can be computed by having saved the value of *lenp
before the call, and subtracting the after-call value of *lenp
from it.
If you need a copy of the string, see "bytes_from_utf8".
U8* utf8_to_bytes(U8 *s, STRLEN *lenp)
utf8_to_uvchr
DEPRECATED!
It is planned to remove utf8_to_uvchr
from a future release of Perl. Do not use it for new code; remove it from existing code.
Returns the native code point of the first character in the string s
which is assumed to be in UTF-8 encoding; retlen
will be set to the length, in bytes, of that character.
Some, but not all, UTF-8 malformations are detected, and in fact, some malformed input could cause reading beyond the end of the input buffer, which is why this function is deprecated. Use "utf8_to_uvchr_buf" instead.
If s
points to one of the detected malformations, and UTF8 warnings are enabled, zero is returned and *retlen
is set (if retlen
isn't NULL
) to -1. If those warnings are off, the computed value if well-defined (or the Unicode REPLACEMENT CHARACTER, if not) is silently returned, and *retlen
is set (if retlen
isn't NULL) so that (
) is the next possible position in s
+ *retlen
s
that could begin a non-malformed character. See "utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvchr(const U8 *s, STRLEN *retlen)
utf8_to_uvchr_buf
Returns the native code point of the first character in the string s
which is assumed to be in UTF-8 encoding; send
points to 1 beyond the end of s
. *retlen
will be set to the length, in bytes, of that character.
If s
does not point to a well-formed UTF-8 character and UTF8 warnings are enabled, zero is returned and *retlen
is set (if retlen
isn't NULL
) to -1. If those warnings are off, the computed value, if well-defined (or the Unicode REPLACEMENT CHARACTER if not), is silently returned, and *retlen
is set (if retlen
isn't NULL
) so that (
) is the next possible position in s
+ *retlen
s
that could begin a non-malformed character. See "utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvchr_buf(const U8 *s, const U8 *send, STRLEN *retlen)
UVCHR_IS_INVARIANT
Evaluates to 1 if the representation of code point cp
is the same whether or not it is encoded in UTF-8; otherwise evaluates to 0. UTF-8 invariant characters can be copied as-is when converting to/from UTF-8, saving time. cp
is Unicode if above 255; otherwise is platform-native.
bool UVCHR_IS_INVARIANT(UV cp)
UVCHR_SKIP
returns the number of bytes required to represent the code point cp
when encoded as UTF-8. cp
is a native (ASCII or EBCDIC) code point if less than 255; a Unicode code point otherwise.
STRLEN UVCHR_SKIP(UV cp)
uvchr_to_utf8
Adds the UTF-8 representation of the native code point uv
to the end of the string d
; d
should have at least UVCHR_SKIP(uv)+1
(up to UTF8_MAXBYTES+1
) free bytes available. The return value is the pointer to the byte after the end of the new character. In other words,
d = uvchr_to_utf8(d, uv);
is the recommended wide native character-aware way of saying
*(d++) = uv;
This function accepts any code point from 0..IV_MAX
as input. IV_MAX
is typically 0x7FFF_FFFF in a 32-bit word.
It is possible to forbid or warn on non-Unicode code points, or those that may be problematic by using "uvchr_to_utf8_flags".
U8* uvchr_to_utf8(U8 *d, UV uv)
uvchr_to_utf8_flags
Adds the UTF-8 representation of the native code point uv
to the end of the string d
; d
should have at least UVCHR_SKIP(uv)+1
(up to UTF8_MAXBYTES+1
) free bytes available. The return value is the pointer to the byte after the end of the new character. In other words,
d = uvchr_to_utf8_flags(d, uv, flags);
or, in most cases,
d = uvchr_to_utf8_flags(d, uv, 0);
This is the Unicode-aware way of saying
*(d++) = uv;
If flags
is 0, this function accepts any code point from 0..IV_MAX
as input. IV_MAX
is typically 0x7FFF_FFFF in a 32-bit word.
Specifying flags
can further restrict what is allowed and not warned on, as follows:
If uv
is a Unicode surrogate code point and UNICODE_WARN_SURROGATE
is set, the function will raise a warning, provided UTF8 warnings are enabled. If instead UNICODE_DISALLOW_SURROGATE
is set, the function will fail and return NULL. If both flags are set, the function will both warn and return NULL.
Similarly, the UNICODE_WARN_NONCHAR
and UNICODE_DISALLOW_NONCHAR
flags affect how the function handles a Unicode non-character.
And likewise, the UNICODE_WARN_SUPER
and UNICODE_DISALLOW_SUPER
flags affect the handling of code points that are above the Unicode maximum of 0x10FFFF. Languages other than Perl may not be able to accept files that contain these.
The flag UNICODE_WARN_ILLEGAL_INTERCHANGE
selects all three of the above WARN flags; and UNICODE_DISALLOW_ILLEGAL_INTERCHANGE
selects all three DISALLOW flags. UNICODE_DISALLOW_ILLEGAL_INTERCHANGE
restricts the allowed inputs to the strict UTF-8 traditionally defined by Unicode. Similarly, UNICODE_WARN_ILLEGAL_C9_INTERCHANGE
and UNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE
are shortcuts to select the above-Unicode and surrogate flags, but not the non-character ones, as defined in Unicode Corrigendum #9. See "Noncharacter code points" in perlunicode.
Extremely high code points were never specified in any standard, and require an extension to UTF-8 to express, which Perl does. It is likely that programs written in something other than Perl would not be able to read files that contain these; nor would Perl understand files written by something that uses a different extension. For these reasons, there is a separate set of flags that can warn and/or disallow these extremely high code points, even if other above-Unicode ones are accepted. They are the UNICODE_WARN_PERL_EXTENDED
and UNICODE_DISALLOW_PERL_EXTENDED
flags. For more information see "UTF8_GOT_PERL_EXTENDED"
. Of course UNICODE_DISALLOW_SUPER
will treat all above-Unicode code points, including these, as malformations. (Note that the Unicode standard considers anything above 0x10FFFF to be illegal, but there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym for UNICODE_WARN_PERL_EXTENDED
is retained for backward compatibility: UNICODE_WARN_ABOVE_31_BIT
. Similarly, UNICODE_DISALLOW_ABOVE_31_BIT
is usable instead of the more accurately named UNICODE_DISALLOW_PERL_EXTENDED
. The names are misleading because on EBCDIC platforms,these flags can apply to code points that actually do fit in 31 bits. The new names accurately describe the situation in all cases.
U8* uvchr_to_utf8_flags(U8 *d, UV uv, UV flags)
uvchr_to_utf8_flags_msgs
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use "uvchr_to_utf8_flags"()
rather than call this directly.
This function is for code that wants any warning and/or error messages to be returned to the caller rather than be displayed. All messages that would have been displayed if all lexical warnings are enabled will be returned.
It is just like "uvchr_to_utf8_flags"
but it takes an extra parameter placed after all the others, msgs
. If this parameter is 0, this function behaves identically to "uvchr_to_utf8_flags"
. Otherwise, msgs
should be a pointer to an HV *
variable, in which this function creates a new HV to contain any appropriate messages. The hash has three key-value pairs, as follows:
text
The text of the message as a SVpv
.
warn_categories
The warning category (or categories) packed into a SVuv
.
flag
A single flag bit associated with this message, in a SVuv
. The bit corresponds to some bit in the *errors
return value, such as UNICODE_GOT_SURROGATE
.
It's important to note that specifying this parameter as non-null will cause any warnings this function would otherwise generate to be suppressed, and instead be placed in *msgs
. The caller can check the lexical warnings state (or not) when choosing what to do with the returned messages.
The caller, of course, is responsible for freeing any returned HV.
U8* uvchr_to_utf8_flags_msgs(U8 *d, UV uv, UV flags, HV ** msgs)
C_ARRAY_END
Returns a pointer to one element past the final element of the input C array.
void * C_ARRAY_END(void *a)
C_ARRAY_LENGTH
Returns the number of elements in the input C array (so you want your zero-based indices to be less than but not equal to).
STRLEN C_ARRAY_LENGTH(void *a)
IN_PERL_COMPILETIME
Returns 1 if this macro is being called during the compilation phase of the program; otherwise 0;
bool IN_PERL_COMPILETIME
IN_PERL_RUNTIME
Returns 1 if this macro is being called during the execution phase of the program; otherwise 0;
bool IN_PERL_RUNTIME
IS_SAFE_SYSCALL
Same as "is_safe_syscall".
bool IS_SAFE_SYSCALL(NN const char *pv, STRLEN len, NN const char *what, NN const char *op_name)
is_safe_syscall
Test that the given pv
(with length len
) doesn't contain any internal NUL
characters. If it does, set errno
to ENOENT
, optionally warn using the syscalls
category, and return FALSE.
Return TRUE if the name is safe.
what
and op_name
are used in any warning.
Used by the IS_SAFE_SYSCALL()
macro.
bool is_safe_syscall(const char *pv, STRLEN len, const char *what, const char *op_name)
my_setenv
A wrapper for the C library setenv(3). Don't use the latter, as the perl version has desirable safeguards
void my_setenv(const char* nam, const char* val)
phase_name
Returns the given phase's name as a NUL-terminated string.
For example, to print a stack trace that includes the current interpreter phase you might do:
const char* phase_name = phase_name(PL_phase); mess("This is weird. (Perl phase: %s)", phase_name);
const char *const phase_name(enum perl_phase)
Poison
PoisonWith(0xEF) for catching access to freed memory.
void Poison(void* dest, int nitems, type)
PoisonFree
PoisonWith(0xEF) for catching access to freed memory.
void PoisonFree(void* dest, int nitems, type)
PoisonNew
PoisonWith(0xAB) for catching access to allocated but uninitialized memory.
void PoisonNew(void* dest, int nitems, type)
PoisonWith
Fill up memory with a byte pattern (a byte repeated over and over again) that hopefully catches attempts to access uninitialized memory.
void PoisonWith(void* dest, int nitems, type, U8 byte)
StructCopy
This is an architecture-independent macro to copy one structure to another.
void StructCopy(type *src, type *dest, type)
sv_destroyable
Dummy routine which reports that object can be destroyed when there is no sharing module present. It ignores its single SV argument, and returns 'true'. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
bool sv_destroyable(SV *sv)
sv_nosharing
Dummy routine which "shares" an SV when there is no sharing module present. Or "locks" it. Or "unlocks" it. In other words, ignores its single SV argument. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
void sv_nosharing(SV *sv)
new_version
Returns a new version object based on the passed in SV:
SV *sv = new_version(SV *ver);
Does not alter the passed in ver SV. See "upg_version" if you want to upgrade the SV.
SV* new_version(SV *ver)
PERL_REVISION
DEPRECATED!
It is planned to remove PERL_REVISION
from a future release of Perl. Do not use it for new code; remove it from existing code.
The major number component of the perl interpreter currently being compiled or executing. This has been 5
from 1993 into 2020.
Instead use one of the version comparison macros. See "PERL_VERSION_EQ"
.
PERL_SUBVERSION
DEPRECATED!
It is planned to remove PERL_SUBVERSION
from a future release of Perl. Do not use it for new code; remove it from existing code.
The micro number component of the perl interpreter currently being compiled or executing. In stable releases this gives the dot release number for maintenance updates. In development releases this gives a tag for a snapshot of the status at various points in the development cycle.
Instead use one of the version comparison macros. See "PERL_VERSION_EQ"
.
PERL_VERSION
DEPRECATED!
It is planned to remove PERL_VERSION
from a future release of Perl. Do not use it for new code; remove it from existing code.
The minor number component of the perl interpreter currently being compiled or executing. Between 1993 into 2020, this has ranged from 0 to 33.
Instead use one of the version comparison macros. See "PERL_VERSION_EQ"
.
PERL_VERSION_EQ
PERL_VERSION_NE
PERL_VERSION_LT
PERL_VERSION_LE
PERL_VERSION_GT
PERL_VERSION_GE
Returns whether or not the perl currently being compiled has the specified relationship to the perl given by the parameters. For example,
#if PERL_VERSION_GT(5,24,2) code that will only be compiled on perls after v5.24.2 #else fallback code #endif
Note that this is usable in making compile-time decisions
You may use the special value '*' for the final number to mean ALL possible values for it. Thus,
#if PERL_VERSION_EQ(5,31,'*')
means all perls in the 5.31 series. And
#if PERL_VERSION_NE(5,24,'*')
means all perls EXCEPT 5.24 ones. And
#if PERL_VERSION_LE(5,9,'*')
is effectively
#if PERL_VERSION_LT(5,10,0)
This means you don't have to think so much when converting from the existing deprecated PERL_VERSION
to using this macro:
#if PERL_VERSION <= 9
becomes
#if PERL_VERSION_LE(5,9,'*')
bool PERL_VERSION_EQ(const U8 major, const U8 minor, const U8 patch)
prescan_version
Validate that a given string can be parsed as a version object, but doesn't actually perform the parsing. Can use either strict or lax validation rules. Can optionally set a number of hint variables to save the parsing code some time when tokenizing.
const char* prescan_version(const char *s, bool strict, const char** errstr, bool *sqv, int *ssaw_decimal, int *swidth, bool *salpha)
scan_version
Returns a pointer to the next character after the parsed version string, as well as upgrading the passed in SV to an RV.
Function must be called with an already existing SV like
sv = newSV(0); s = scan_version(s, SV *sv, bool qv);
Performs some preprocessing to the string to ensure that it has the correct characteristics of a version. Flags the object if it contains an underscore (which denotes this is an alpha version). The boolean qv denotes that the version should be interpreted as if it had multiple decimals, even if it doesn't.
const char* scan_version(const char *s, SV *rv, bool qv)
upg_version
In-place upgrade of the supplied SV to a version object.
SV *sv = upg_version(SV *sv, bool qv);
Returns a pointer to the upgraded SV. Set the boolean qv if you want to force this SV to be interpreted as an "extended" version.
SV* upg_version(SV *ver, bool qv)
vcmp
Version object aware cmp. Both operands must already have been converted into version objects.
int vcmp(SV *lhv, SV *rhv)
vnormal
Accepts a version object and returns the normalized string representation. Call like:
sv = vnormal(rv);
NOTE: you can pass either the object directly or the SV contained within the RV.
The SV returned has a refcount of 1.
SV* vnormal(SV *vs)
vnumify
Accepts a version object and returns the normalized floating point representation. Call like:
sv = vnumify(rv);
NOTE: you can pass either the object directly or the SV contained within the RV.
The SV returned has a refcount of 1.
SV* vnumify(SV *vs)
vstringify
In order to maintain maximum compatibility with earlier versions of Perl, this function will return either the floating point notation or the multiple dotted notation, depending on whether the original version contained 1 or more dots, respectively.
The SV returned has a refcount of 1.
SV* vstringify(SV *vs)
vverify
Validates that the SV contains valid internal structure for a version object. It may be passed either the version object (RV) or the hash itself (HV). If the structure is valid, it returns the HV. If the structure is invalid, it returns NULL.
SV *hv = vverify(sv);
Note that it only confirms the bare minimum structure (so as not to get confused by derived classes which may contain additional hash entries):
SV* vverify(SV *vs)
In all these calls, the U32 wn
parameters are warning category constants. You can see the ones currently available in "Category Hierarchy" in warnings, just capitalize all letters in the names and prefix them by WARN_
. So, for example, the category void
used in a perl program becomes WARN_VOID
when used in XS code and passed to one of the calls below.
ckWARN
ckWARN2
ckWARN3
ckWARN4
These return a boolean as to whether or not warnings are enabled for any of the warning category(ies) parameters: w
, w1
, ....
Should any of the categories by default be enabled even if not within the scope of
, instead use the use warnings
"ckWARN_d"
macros.
The categories must be completely independent, one may not be subclassed from the other.
bool ckWARN (U32 w) bool ckWARN2(U32 w1, U32 w2) bool ckWARN3(U32 w1, U32 w2, U32 w3) bool ckWARN4(U32 w1, U32 w2, U32 w3, U32 w4)
ckWARN_d
ckWARN2_d
ckWARN3_d
ckWARN4_d
Like "ckWARN"
, but for use if and only if the warning category(ies) is by default enabled even if not within the scope of
.use warnings
bool ckWARN_d (U32 w) bool ckWARN2_d(U32 w1, U32 w2) bool ckWARN3_d(U32 w1, U32 w2, U32 w3) bool ckWARN4_d(U32 w1, U32 w2, U32 w3, U32 w4)
ck_warner
ck_warner_d
If none of the warning categories given by err
are enabled, do nothing; otherwise call "warner"
or "warner_nocontext"
with the passed-in parameters;.
err
must be one of the "packWARN"
, packWARN2
, packWARN3
, packWARN4
macros populated with the appropriate number of warning categories.
The two forms differ only in that ck_warner_d
should be used if warnings for any of the categories are by default enabled.
NOTE: ck_warner
must be explicitly called as Perl_ck_warner
with an aTHX_
parameter.
NOTE: ck_warner_d
must be explicitly called as Perl_ck_warner_d
with an aTHX_
parameter.
void Perl_ck_warner(pTHX_ U32 err, const char* pat, ...)
CLEAR_ERRSV
Clear the contents of $@
, setting it to the empty string.
This replaces any read-only SV with a fresh SV and removes any magic.
void CLEAR_ERRSV()
croak
croak_nocontext
These are XS interfaces to Perl's die
function.
They take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv"
.
The error message will be used as an exception, by default returning control to the nearest enclosing eval
, but subject to modification by a $SIG{__DIE__}
handler. In any case, these croak functions never return normally.
For historical reasons, if pat
is null then the contents of ERRSV
($@
) will be used as an error message or object instead of building an error message from arguments. If you want to throw a non-string object, or build an error message in an SV yourself, it is preferable to use the "croak_sv"
function, which does not involve clobbering ERRSV
.
The two forms differ only in that croak_nocontext
does not take a thread context (aTHX
) parameter. It is usually preferred as it takes up fewer bytes of code than plain Perl_croak
, and time is rarely a critical resource when you are about to throw an exception.
NOTE: croak
must be explicitly called as Perl_croak
with an aTHX_
parameter.
void Perl_croak (pTHX_ const char* pat, ...) void croak_nocontext(const char* pat, ...)
croak_no_modify
This encapsulates a common reason for dying, generating terser object code than using the generic Perl_croak
. It is exactly equivalent to Perl_croak(aTHX_ "%s", PL_no_modify)
(which expands to something like "Modification of a read-only value attempted").
Less code used on exception code paths reduces CPU cache pressure.
void croak_no_modify()
croak_sv
This is an XS interface to Perl's die
function.
baseex
is the error message or object. If it is a reference, it will be used as-is. Otherwise it is used as a string, and if it does not end with a newline then it will be extended with some indication of the current location in the code, as described for "mess_sv".
The error message or object will be used as an exception, by default returning control to the nearest enclosing eval
, but subject to modification by a $SIG{__DIE__}
handler. In any case, the croak_sv
function never returns normally.
To die with a simple string message, the "croak" function may be more convenient.
void croak_sv(SV *baseex)
die
die_nocontext
These behave the same as "croak", except for the return type. They should be used only where the OP *
return type is required. They never actually return.
The two forms differ only in that die_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: die
must be explicitly called as Perl_die
with an aTHX_
parameter.
OP* Perl_die (pTHX_ const char* pat, ...) OP* die_nocontext(const char* pat, ...)
die_sv
This behaves the same as "croak_sv", except for the return type. It should be used only where the OP *
return type is required. The function never actually returns.
OP* die_sv(SV *baseex)
packWARN
packWARN2
packWARN3
packWARN4
These macros are used to pack warning categories into a single U32 to pass to macros and functions that take a warning category parameter. The number of categories to pack is given by the name, with a corresponding number of category parameters passed.
U32 packWARN (U32 w1) U32 packWARN2(U32 w1, U32 w2) U32 packWARN3(U32 w1, U32 w2, U32 w3) U32 packWARN4(U32 w1, U32 w2, U32 w3, U32 w4)
SANE_ERRSV
Clean up ERRSV so we can safely set it.
This replaces any read-only SV with a fresh writable copy and removes any magic.
void SANE_ERRSV()
vcroak
This is an XS interface to Perl's die
function.
pat
and args
are a sprintf-style format pattern and encapsulated argument list. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv".
The error message will be used as an exception, by default returning control to the nearest enclosing eval
, but subject to modification by a $SIG{__DIE__}
handler. In any case, the croak
function never returns normally.
For historical reasons, if pat
is null then the contents of ERRSV
($@
) will be used as an error message or object instead of building an error message from arguments. If you want to throw a non-string object, or build an error message in an SV yourself, it is preferable to use the "croak_sv" function, which does not involve clobbering ERRSV
.
void vcroak(const char* pat, va_list* args)
vwarn
This is an XS interface to Perl's warn
function.
This is like "warn"
, but args
are an encapsulated argument list.
Unlike with "vcroak", pat
is not permitted to be null.
void vwarn(const char* pat, va_list* args)
vwarner
This is like "warner"
, but args
are an encapsulated argument list.
void vwarner(U32 err, const char* pat, va_list* args)
warn
warn_nocontext
These are XS interfaces to Perl's warn
function.
They take a sprintf-style format pattern and argument list, which are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv"
.
The error message or object will by default be written to standard error, but this is subject to modification by a $SIG{__WARN__}
handler.
Unlike with "croak"
, pat
is not permitted to be null.
The two forms differ only in that warn_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
NOTE: warn
must be explicitly called as Perl_warn
with an aTHX_
parameter.
void Perl_warn (pTHX_ const char* pat, ...) void warn_nocontext(const char* pat, ...)
warner
warner_nocontext
These output a warning of the specified category (or categories) given by err
, using the sprintf-style format pattern pat
, and argument list.
err
must be one of the "packWARN"
, packWARN2
, packWARN3
, packWARN4
macros populated with the appropriate number of warning categories. If any of the warning categories they specify is fatal, a fatal exception is thrown.
In any event a message is generated by the pattern and arguments. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for "mess_sv".
The error message or object will by default be written to standard error, but this is subject to modification by a $SIG{__WARN__}
handler.
pat
is not permitted to be null.
The two forms differ only in that warner_nocontext
does not take a thread context (aTHX
) parameter, so is used in situations where the caller doesn't already have the thread context.
These functions differ from the similarly named "warn"
functions, in that the latter are for XS code to unconditionally display a warning, whereas these are for code that may be compiling a perl program, and does extra checking to see if the warning should be fatal.
NOTE: warner
must be explicitly called as Perl_warner
with an aTHX_
parameter.
void Perl_warner (pTHX_ U32 err, const char* pat, ...) void warner_nocontext(U32 err, const char* pat, ...)
warn_sv
This is an XS interface to Perl's warn
function.
baseex
is the error message or object. If it is a reference, it will be used as-is. Otherwise it is used as a string, and if it does not end with a newline then it will be extended with some indication of the current location in the code, as described for "mess_sv".
The error message or object will by default be written to standard error, but this is subject to modification by a $SIG{__WARN__}
handler.
To warn with a simple string message, the "warn" function may be more convenient.
void warn_sv(SV *baseex)
xsubpp compiles XS code into C. See "xsubpp" in perlutil.
aMY_CXT
Described in perlxs.
aMY_CXT_
Described in perlxs.
_aMY_CXT
Described in perlxs.
ax
Variable which is setup by xsubpp
to indicate the stack base offset, used by the ST
, XSprePUSH
and XSRETURN
macros. The dMARK
macro must be called prior to setup the MARK
variable.
I32 ax
CLASS
Variable which is setup by xsubpp
to indicate the class name for a C++ XS constructor. This is always a char*
. See "THIS"
.
char* CLASS
dAX
Sets up the ax
variable. This is usually handled automatically by xsubpp
by calling dXSARGS
.
dAX;
dAXMARK
Sets up the ax
variable and stack marker variable mark
. This is usually handled automatically by xsubpp
by calling dXSARGS
.
dAXMARK;
dITEMS
Sets up the items
variable. This is usually handled automatically by xsubpp
by calling dXSARGS
.
dITEMS;
dMY_CXT
Described in perlxs.
dUNDERBAR
Sets up any variable needed by the UNDERBAR
macro. It used to define padoff_du
, but it is currently a noop. However, it is strongly advised to still use it for ensuring past and future compatibility.
dUNDERBAR;
dXSARGS
Sets up stack and mark pointers for an XSUB, calling dSP
and dMARK
. Sets up the ax
and items
variables by calling dAX
and dITEMS
. This is usually handled automatically by xsubpp
.
dXSARGS;
dXSI32
Sets up the ix
variable for an XSUB which has aliases. This is usually handled automatically by xsubpp
.
dXSI32;
items
Variable which is setup by xsubpp
to indicate the number of items on the stack. See "Variable-length Parameter Lists" in perlxs.
I32 items
ix
Variable which is setup by xsubpp
to indicate which of an XSUB's aliases was used to invoke it. See "The ALIAS: Keyword" in perlxs.
I32 ix
MY_CXT
Described in perlxs.
MY_CXT_CLONE
Described in perlxs.
MY_CXT_INIT
Described in perlxs.
pMY_CXT
Described in perlxs.
pMY_CXT_
Described in perlxs.
_pMY_CXT
Described in perlxs.
RETVAL
Variable which is setup by xsubpp
to hold the return value for an XSUB. This is always the proper type for the XSUB. See "The RETVAL Variable" in perlxs.
type RETVAL
START_MY_CXT
Described in perlxs.
THIS
Variable which is setup by xsubpp
to designate the object in a C++ XSUB. This is always the proper type for the C++ object. See "CLASS"
and "Using XS With C++" in perlxs.
type THIS
XS
Macro to declare an XSUB and its C parameter list. This is handled by xsubpp
. It is the same as using the more explicit XS_EXTERNAL
macro; the latter is preferred.
XS_INTERNAL
Macro to declare an XSUB and its C parameter list without exporting the symbols. This is handled by xsubpp
and generally preferable over exporting the XSUB symbols unnecessarily.
XSPROTO
Macro used by "XS_INTERNAL"
and "XS_EXTERNAL"
to declare a function prototype. You probably shouldn't be using this directly yourself.
The following functions have been flagged as part of the public API, but are currently undocumented. Use them at your own risk, as the interfaces are subject to change. Functions that are not listed in this document are not intended for public use, and should NOT be used under any circumstances.
If you feel you need to use one of these functions, first send email to perl5-porters@perl.org. It may be that there is a good reason for the function not being documented, and it should be removed from this list; or it may just be that no one has gotten around to documenting it. In the latter case, you will be asked to submit a patch to document the function. Once your patch is accepted, it will indicate that the interface is stable (unless it is explicitly marked otherwise) and usable by you.
clone_params_del gv_name_set newANONSUB save_helem clone_params_new hv_free_ent newAVREF save_helem_flags do_close hv_ksplit newCVREF save_pushi32ptr do_open hv_name_set newGVREF save_pushptr do_openn my_failure_exit newHVREF save_pushptrptr gv_autoload_pv newANONATTRSUB newSVREF start_subparse gv_autoload_pvn newANONHASH save_aelem sv_dup gv_autoload_sv newANONLIST save_aelem_flags sv_dup_inc
Until May 1997, this document was maintained by Jeff Okamoto <okamoto@corp.hp.com>. It is now maintained as part of Perl itself.
With lots of help and suggestions from Dean Roehrich, Malcolm Beattie, Andreas Koenig, Paul Hudson, Ilya Zakharevich, Paul Marquess, Neil Bowers, Matthew Green, Tim Bunce, Spider Boardman, Ulrich Pfeifer, Stephen McCamant, and Gurusamy Sarathy.
API Listing originally by Dean Roehrich <roehrich@cray.com>.
Updated to be autogenerated from comments in the source by Benjamin Stuhl.
config.h, perlapio, perlcall, perlclib, perlembed, perlfilter, perlguts, perlhacktips, perlintern, perlinterp, perliol, perlmroapi, perlreapi, perlreguts, perlxs