perlapi - autogenerated documentation for the perl public API
This file contains the documentation of the perl public API generated byembed.pl, specifically a listing of functions, macros, flags, and variables that may be used by extension writers.At the end is a list of functions which have yet to be documented. The interfaces of those are subject to change without notice. Anything not listed here 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 embeddedNUL
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 thePL_
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 somethimes 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 (Seeperlebcdic). 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 toutf8
(and variants of that name, including in function names), it also (essentially transparently) meansUTF-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 listing below is alphabetical, case insensitive.
Frees the 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.
voidav_clear(AV *av)
NOTE: this function is experimental and may change or be removed without notice.
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.
voidav_create_and_push(AV **const avp, SV *const val)
NOTE: this function is experimental and may change or be removed without notice.
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.
SV**av_create_and_unshift_one(AV **const avp, SV *const val)
Deletes the element indexed bykey
from the array, makes the element mortal, and returns it. Ifflags
equalsG_DISCARD
, the element is freed and null is returned. Perl equivalent:my $elem = delete($myarray[$idx]);
for the non-G_DISCARD
version and a void-contextdelete($myarray[$idx]);
for theG_DISCARD
version.
SV*av_delete(AV *av, SSize_t key, I32 flags)
Returns true if the element indexed bykey
has been initialized.
This relies on the fact that uninitialized array elements are set toNULL
.
Perl equivalent:exists($myarray[$key])
.
boolav_exists(AV *av, SSize_t key)
Pre-extend an array. Thekey
is the index to which the array should be extended.
voidav_extend(AV *av, SSize_t key)
Returns the SV at the specified index in the array. Thekey
is the index. If lval is true, you are guaranteed to get a real SV back (in case it wasn't real before), which you can then modify. Check that the return value is non-null before dereferencing it to aSV*
.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
The rough perl equivalent is$myarray[$idx]
.
SV**av_fetch(AV *av, SSize_t key, I32 lval)
Same asav_top_index()
. Deprecated, useav_top_index()
instead.
intAvFILL(AV* av)
Set the highest index in the array to the given number, equivalent to Perl's$#array = $fill;
.
The number of elements in the array will befill + 1
afterav_fill()
returns. If the array was previously shorter, then the additional elements appended are set to NULL. If the array was longer, then the excess elements are freed.av_fill(av, -1)
is the same asav_clear(av)
.
voidav_fill(AV *av, SSize_t fill)
Same as"av_top_index". Note that, unlike what the name implies, it returns the highest index in the array, so to get the size of the array you need to useav_len(av) + 1
. This is unlike"sv_len", which returns what you would expect.
SSize_tav_len(AV *av)
Creates a new AV and populates it with a list of SVs. The SVs are copied into the array, so they may be freed after the call toav_make
. The new AV will have a reference count of 1.
Perl equivalent:my @new_array = ($scalar1, $scalar2, $scalar3...);
AV*av_make(SSize_t size, SV **strp)
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)
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, $elem;
.
voidav_push(AV *av, SV *val)
Removes one SV from the start of the array, reducing its size by one and returning the SV (transferring control of one reference count) to the caller. Returns&PL_sv_undef
if the array is empty.
Perl equivalent:shift(@myarray);
SV*av_shift(AV *av)
Stores an SV in an array. The array index is specified askey
. The return value will beNULL
if the operation failed or if the value did not need to be actually stored within the array (as in the case of tied arrays). Otherwise, it can be dereferenced to get theSV*
that was stored there (=val
)).
Note that the caller is responsible for suitably incrementing the reference count ofval
before the call, and decrementing it if the function returnedNULL
.
Approximate Perl equivalent:$myarray[$key] = $val;
.
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
SV**av_store(AV *av, SSize_t key, SV *val)
Same asav_top_index()
.
intav_tindex(AV* av)
Returns the highest index in the array. The number of elements in the array isav_top_index(av) + 1
. Returns -1 if the array is empty.
The Perl equivalent for this is$#myarray
.
(A slightly shorter form isav_tindex
.)
SSize_tav_top_index(AV *av)
Undefines the array. The XS equivalent ofundef(@array)
.
As well as freeing all the elements of the array (likeav_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.
voidav_undef(AV *av)
Unshift the given number ofundef
values onto the beginning of the array. The array will grow automatically to accommodate the addition. You must then useav_store
to assign values to these new elements.
Perl equivalent:unshift @myarray, ( (undef) x $n );
voidav_unshift(AV *av, SSize_t num)
Returns the AV of the specified Perl global or package array with the given name (so it won't work on lexical variables).flags
are passed togv_fetchpv
. IfGV_ADD
is set and the Perl variable does not exist then it will be created. Ifflags
is zero and the variable does not exist then NULL is returned.
Perl equivalent:@{"$name"}
.
NOTE: the perl_ form of this function is deprecated.
AV*get_av(const char *name, I32 flags)
Creates a new AV. The reference count is set to 1.
Perl equivalent:my @array;
.
AV*newAV()
Sort an array. Here is an example:
sortsv(AvARRAY(av), av_top_index(av)+1, Perl_sv_cmp_locale);
Currently this always uses mergesort. See"sortsv_flags"
for a more flexible routine.
voidsortsv(SV** array, size_t num_elts, SVCOMPARE_t cmp)
Sort an array, with various options.
voidsortsv_flags(SV** array, size_t num_elts, SVCOMPARE_t cmp, U32 flags)
Performs a callback to the specified named and package-scoped Perl subroutine withargv
(aNULL
-terminated array of strings) as arguments. Seeperlcall.
Approximate Perl equivalent:&{"$sub_name"}(@$argv)
.
NOTE: the perl_ form of this function is deprecated.
I32call_argv(const char* sub_name, I32 flags, char** argv)
Performs a callback to the specified Perl method. The blessed object must be on the stack. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_method(const char* methname, I32 flags)
Performs a callback to the specified Perl sub. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_pv(const char* sub_name, I32 flags)
Performs a callback to the Perl sub specified by the SV.
If neither theG_METHOD
norG_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 orSvPV(sv)
will be used as the name of the sub to call.
If theG_METHOD
flag is supplied, the SV may be a reference to a CV orSvPV(sv)
will be used as the name of the method to call.
If theG_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.
Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32call_sv(SV* sv, VOL I32 flags)
Opening bracket on a callback. See"LEAVE"
andperlcall.
ENTER;
Tells Perl toeval
the given string in scalar context and return an SV* result.
NOTE: the perl_ form of this function is deprecated.
SV*eval_pv(const char* p, I32 croak_on_error)
Tells Perl toeval
the string in the SV. It supports the same flags ascall_sv
, with the obvious exception ofG_EVAL
. Seeperlcall.
NOTE: the perl_ form of this function is deprecated.
I32eval_sv(SV* sv, I32 flags)
Closing bracket for temporaries on a callback. See"SAVETMPS"
andperlcall.
FREETMPS;
Closing bracket on a callback. See"ENTER"
andperlcall.
LEAVE;
Opening bracket for temporaries on a callback. See"FREETMPS"
andperlcall.
SAVETMPS;
Converts the specified character to foldcase. If the input is anything but an ASCII uppercase character, that input character itself is returned. VarianttoFOLD_A
is equivalent. (There is no equivalentto_FOLD_L1
for the full Latin1 range, as the full generality of"toFOLD_uvchr" is needed there.)
U8toFOLD(U8 ch)
Converts the UTF-8 encoded character atp
to its foldcase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the foldcase version may be longer than the original character.
The first code point of the foldcased version is returned (but note, as explained just above, that there may be more.)
The input character atp
is assumed to be well-formed.
UVtoFOLD_utf8(U8* p, U8* s, STRLEN* lenp)
Converts the code pointcp
to its foldcase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. The code point is interpreted as native if less than 256; otherwise as Unicode. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the foldcase version may be longer than the original character.
The first code point of the foldcased version is returned (but note, as explained just above, that there may be more.)
UVtoFOLD_uvchr(UV cp, U8* s, STRLEN* lenp)
Converts the specified character to lowercase. If the input is anything but an ASCII uppercase character, that input character itself is returned. VarianttoLOWER_A
is equivalent.
U8toLOWER(U8 ch)
Converts the specified Latin1 character to lowercase. The results are undefined if the input doesn't fit in a byte.
U8toLOWER_L1(U8 ch)
Converts the specified character to lowercase using the current locale's rules, if possible; otherwise returns the input character itself.
U8toLOWER_LC(U8 ch)
Converts the UTF-8 encoded character atp
to its lowercase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the lowercase version may be longer than the original character.
The first code point of the lowercased version is returned (but note, as explained just above, that there may be more.)
The input character atp
is assumed to be well-formed.
UVtoLOWER_utf8(U8* p, U8* s, STRLEN* lenp)
Converts the code pointcp
to its lowercase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. The code point is interpreted as native if less than 256; otherwise as Unicode. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the lowercase version may be longer than the original character.
The first code point of the lowercased version is returned (but note, as explained just above, that there may be more.)
UVtoLOWER_uvchr(UV cp, U8* s, STRLEN* lenp)
Converts the specified character to titlecase. If the input is anything but an ASCII lowercase character, that input character itself is returned. VarianttoTITLE_A
is equivalent. (There is notoTITLE_L1
for the full Latin1 range, as the full generality of"toTITLE_uvchr" is needed there. Titlecase is not a concept used in locale handling, so there is no functionality for that.)
U8toTITLE(U8 ch)
Converts the UTF-8 encoded character atp
to its titlecase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the titlecase version may be longer than the original character.
The first code point of the titlecased version is returned (but note, as explained just above, that there may be more.)
The input character atp
is assumed to be well-formed.
UVtoTITLE_utf8(U8* p, U8* s, STRLEN* lenp)
Converts the code pointcp
to its titlecase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. The code point is interpreted as native if less than 256; otherwise as Unicode. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the titlecase version may be longer than the original character.
The first code point of the titlecased version is returned (but note, as explained just above, that there may be more.)
UVtoTITLE_uvchr(UV cp, U8* s, STRLEN* lenp)
Converts the specified character to uppercase. If the input is anything but an ASCII lowercase character, that input character itself is returned. VarianttoUPPER_A
is equivalent.
U8toUPPER(U8 ch)
Converts the UTF-8 encoded character atp
to its uppercase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the uppercase version may be longer than the original character.
The first code point of the uppercased version is returned (but note, as explained just above, that there may be more.)
The input character atp
is assumed to be well-formed.
UVtoUPPER_utf8(U8* p, U8* s, STRLEN* lenp)
Converts the code pointcp
to its uppercase version, and stores that in UTF-8 ins
, and its length in bytes inlenp
. The code point is interpreted as native if less than 256; otherwise as Unicode. Note that the buffer pointed to bys
needs to be at leastUTF8_MAXBYTES_CASE+1
bytes since the uppercase version may be longer than the original character.
The first code point of the uppercased version is returned (but note, as explained just above, that there may be more.)
UVtoUPPER_uvchr(UV cp, 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 byuse bytes
, and only the ones withLC
in the name are affected by the current locale.
The base function, e.g.,isALPHA()
, takes an octet (either achar
or aU8
) as input and returns a boolean as to whether or not the character represented by that octet 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.
VariantisFOO_A
(e.g.,isALPHA_A()
) is identical to the base function with no suffix"_A"
.
VariantisFOO_L1
imposes the Latin-1 (or EBCDIC equivlalent) 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).
VariantisFOO_uvchr
is like theisFOO_L1
variant, but accepts any UV code point as input. 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.
VariantisFOO_utf8
is likeisFOO_uvchr
, but the input is a pointer to a (known to be well-formed) UTF-8 encoded string (U8*
orchar*
, and possibly containing embeddedNUL
characters). The classification of just the first (possibly multi-byte) character in the string is tested.
VariantisFOO_LC
is like theisFOO_A
andisFOO_L1
variants, but the result is based on the current locale, which is whatLC
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 callingisdigit()
. 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.
VariantisFOO_LC_uvchr
is likeisFOO_LC
, but is defined on any UV. It returns the same asisFOO_LC
for input code points less than 256, and returns the hard-coded, not-affected-by-locale, Unicode results for larger ones.
VariantisFOO_LC_utf8
is likeisFOO_LC_uvchr
, but the input is a pointer to a (known to be well-formed) UTF-8 encoded string (U8*
orchar*
, and possibly containing embeddedNUL
characters). The classification of just the first (possibly multi-byte) character in the string is tested.
Returns a boolean indicating whether the specified character is an alphabetic character, analogous tom/[[:alpha:]]/
. See thetop of this section for an explanation of variantsisALPHA_A
,isALPHA_L1
,isALPHA_uvchr
,isALPHA_utf8
,isALPHA_LC
,isALPHA_LC_uvchr
, andisALPHA_LC_utf8
.
boolisALPHA(char ch)
Returns a boolean indicating whether the specified character is a either an alphabetic character or decimal digit, analogous tom/[[:alnum:]]/
. See thetop of this section for an explanation of variantsisALPHANUMERIC_A
,isALPHANUMERIC_L1
,isALPHANUMERIC_uvchr
,isALPHANUMERIC_utf8
,isALPHANUMERIC_LC
,isALPHANUMERIC_LC_uvchr
, andisALPHANUMERIC_LC_utf8
.
boolisALPHANUMERIC(char ch)
Returns a boolean indicating whether the specified character is one of the 128 characters in the ASCII character set, analogous tom/[[:ascii:]]/
. On non-ASCII platforms, it returns TRUE iff this character corresponds to an ASCII character. VariantsisASCII_A()
andisASCII_L1()
are identical toisASCII()
. See thetop of this section for an explanation of variantsisASCII_uvchr
,isASCII_utf8
,isASCII_LC
,isASCII_LC_uvchr
, andisASCII_LC_utf8
. Note, however, that some platforms do not have the C library routineisascii()
. In these cases, the variants whose names containLC
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 similarlyisASCII_utf8
will work properly on any string encoded or not in UTF-8.
boolisASCII(char ch)
Returns a boolean indicating whether the specified character is a character considered to be a blank, analogous tom/[[:blank:]]/
. See thetop of this section for an explanation of variantsisBLANK_A
,isBLANK_L1
,isBLANK_uvchr
,isBLANK_utf8
,isBLANK_LC
,isBLANK_LC_uvchr
, andisBLANK_LC_utf8
. Note, however, that some platforms do not have the C library routineisblank()
. In these cases, the variants whose names containLC
are the same as the corresponding ones without.
boolisBLANK(char ch)
Returns a boolean indicating whether the specified character is a control character, analogous tom/[[:cntrl:]]/
. See thetop of this section for an explanation of variantsisCNTRL_A
,isCNTRL_L1
,isCNTRL_uvchr
,isCNTRL_utf8
,isCNTRL_LC
,isCNTRL_LC_uvchr
, andisCNTRL_LC_utf8
On EBCDIC platforms, you almost always want to use theisCNTRL_L1
variant.
boolisCNTRL(char ch)
Returns a boolean indicating whether the specified character is a digit, analogous tom/[[:digit:]]/
. VariantsisDIGIT_A
andisDIGIT_L1
are identical toisDIGIT
. See thetop of this section for an explanation of variantsisDIGIT_uvchr
,isDIGIT_utf8
,isDIGIT_LC
,isDIGIT_LC_uvchr
, andisDIGIT_LC_utf8
.
boolisDIGIT(char ch)
Returns a boolean indicating whether the specified character is a graphic character, analogous tom/[[:graph:]]/
. See thetop of this section for an explanation of variantsisGRAPH_A
,isGRAPH_L1
,isGRAPH_uvchr
,isGRAPH_utf8
,isGRAPH_LC
,isGRAPH_LC_uvchr
, andisGRAPH_LC_utf8
.
boolisGRAPH(char ch)
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 propertyXID_Continue
. The difference is that this returns true only if the input character also matches"isWORDCHAR". See thetop of this section for an explanation of variantsisIDCONT_A
,isIDCONT_L1
,isIDCONT_uvchr
,isIDCONT_utf8
,isIDCONT_LC
,isIDCONT_LC_uvchr
, andisIDCONT_LC_utf8
.
boolisIDCONT(char ch)
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 propertyXID_Start
. The difference is that this returns true only if the input character also matches"isWORDCHAR". See thetop of this section for an explanation of variantsisIDFIRST_A
,isIDFIRST_L1
,isIDFIRST_uvchr
,isIDFIRST_utf8
,isIDFIRST_LC
,isIDFIRST_LC_uvchr
, andisIDFIRST_LC_utf8
.
boolisIDFIRST(char ch)
Returns a boolean indicating whether the specified character is a lowercase character, analogous tom/[[:lower:]]/
. See thetop of this section for an explanation of variantsisLOWER_A
,isLOWER_L1
,isLOWER_uvchr
,isLOWER_utf8
,isLOWER_LC
,isLOWER_LC_uvchr
, andisLOWER_LC_utf8
.
boolisLOWER(char ch)
Returns a boolean indicating whether the specified character is an octal digit, [0-7]. The only two variants areisOCTAL_A
andisOCTAL_L1
; each is identical toisOCTAL
.
boolisOCTAL(char ch)
Returns a boolean indicating whether the specified character is a printable character, analogous tom/[[:print:]]/
. See thetop of this section for an explanation of variantsisPRINT_A
,isPRINT_L1
,isPRINT_uvchr
,isPRINT_utf8
,isPRINT_LC
,isPRINT_LC_uvchr
, andisPRINT_LC_utf8
.
boolisPRINT(char ch)
(short for Posix Space) Starting in 5.18, this is identical in all its forms to the correspondingisSPACE()
macros. The locale forms of this macro are identical to their correspondingisSPACE()
forms in all Perl releases. In releases prior to 5.18, the non-locale forms differ from theirisSPACE()
forms only in that theisSPACE()
forms don't match a Vertical Tab, and theisPSXSPC()
forms do. Otherwise they are identical. Thus this macro is analogous to whatm/[[:space:]]/
matches in a regular expression. See thetop of this section for an explanation of variantsisPSXSPC_A
,isPSXSPC_L1
,isPSXSPC_uvchr
,isPSXSPC_utf8
,isPSXSPC_LC
,isPSXSPC_LC_uvchr
, andisPSXSPC_LC_utf8
.
boolisPSXSPC(char ch)
Returns a boolean indicating whether the specified character is a punctuation character, analogous tom/[[: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 thetop of this section for an explanation of variantsisPUNCT_A
,isPUNCT_L1
,isPUNCT_uvchr
,isPUNCT_utf8
,isPUNCT_LC
,isPUNCT_LC_uvchr
, andisPUNCT_LC_utf8
.
boolisPUNCT(char ch)
Returns a boolean indicating whether the specified character is a whitespace character. This is analogous to whatm/\s/
matches in a regular expression. Starting in Perl 5.18 this also matches whatm/[[:space:]]/
does. Prior to 5.18, only the locale forms of this macro (the ones withLC
in their names) matched precisely whatm/[[:space:]]/
does. In those releases, the only difference, in the non-locale variants, was thatisSPACE()
did not match a vertical tab. (See"isPSXSPC" for a macro that matches a vertical tab in all releases.) See thetop of this section for an explanation of variantsisSPACE_A
,isSPACE_L1
,isSPACE_uvchr
,isSPACE_utf8
,isSPACE_LC
,isSPACE_LC_uvchr
, andisSPACE_LC_utf8
.
boolisSPACE(char ch)
Returns a boolean indicating whether the specified character is an uppercase character, analogous tom/[[:upper:]]/
. See thetop of this section for an explanation of variantsisUPPER_A
,isUPPER_L1
,isUPPER_uvchr
,isUPPER_utf8
,isUPPER_LC
,isUPPER_LC_uvchr
, andisUPPER_LC_utf8
.
boolisUPPER(char ch)
Returns a boolean indicating whether the specified character is a character that is a word character, analogous to whatm/\w/
andm/[[: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 thetop of this section for an explanation of variantsisWORDCHAR_A
,isWORDCHAR_L1
,isWORDCHAR_uvchr
, andisWORDCHAR_utf8
.isWORDCHAR_LC
,isWORDCHAR_LC_uvchr
, andisWORDCHAR_LC_utf8
are also as described there, but additionally include the platform's native underscore.
boolisWORDCHAR(char ch)
Returns a boolean indicating whether the specified character is a hexadecimal digit. In the ASCII range these are[0-9A-Fa-f]
. VariantsisXDIGIT_A()
andisXDIGIT_L1()
are identical toisXDIGIT()
. See thetop of this section for an explanation of variantsisXDIGIT_uvchr
,isXDIGIT_utf8
,isXDIGIT_LC
,isXDIGIT_LC_uvchr
, andisXDIGIT_LC_utf8
.
boolisXDIGIT(char ch)
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 usesCOPY_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. IfKEEP_PTR_TABLE
is not set thenperl_clone
will kill the ptr_table using the functionptr_table_free(PL_ptr_table); PL_ptr_table = NULL;
, reason to keep it around is if you want to dup some of your own variable who are outside the graph perl scans, an example of this code is inthreads.xs create.
CLONEf_CLONE_HOST
- This is a win32 thing, it is ignored on unix, it tells perls 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 )
NOTE: this function 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.
voidBhkDISABLE(BHK *hk, which)
NOTE: this function 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.
voidBhkENABLE(BHK *hk, which)
NOTE: this function 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 ofptr
depends on the entry.
voidBhkENTRY_set(BHK *hk, which, void *ptr)
NOTE: this function 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: this function must be explicitly called as Perl_blockhook_register with an aTHX_ parameter.
voidPerl_blockhook_register(pTHX_ BHK *hk)
NOTE: this function 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 hashcophh
.flags
is currently unused and must be zero.
HV *cophh_2hv(const COPHH *cophh, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Make and return a complete copy of the cop hints hashcophh
.
COPHH *cophh_copy(COPHH *cophh)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_delete_pvn", but takes a nul-terminated string instead of a string/length pair.
COPHH *cophh_delete_pv(const COPHH *cophh, const char *key, U32 hash, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Delete a key and its associated value from the cop hints hashcophh
, and returns 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 key is specified bykeypv
andkeylen
. Ifflags
has theCOPHH_KEY_UTF8
bit set, the key octets are interpreted as UTF-8, otherwise they are interpreted as Latin-1.hash
is a precomputed hash of the key string, or zero if it has not been precomputed.
COPHH *cophh_delete_pvn(COPHH *cophh, const char *keypv, STRLEN keylen, U32 hash, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_delete_pvn", but takes aNUL
-terminated literal string instead of a string/length pair, and no precomputed hash.
COPHH *cophh_delete_pvs(const COPHH *cophh, const char *key, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_delete_pvn", but takes a Perl scalar instead of a string/length pair.
COPHH *cophh_delete_sv(const COPHH *cophh, SV *key, U32 hash, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_fetch_pvn", but takes a nul-terminated string instead of a string/length pair.
SV *cophh_fetch_pv(const COPHH *cophh, const char *key, U32 hash, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Look up the entry in the cop hints hashcophh
with the key specified bykeypv
andkeylen
. Ifflags
has theCOPHH_KEY_UTF8
bit set, the key octets are interpreted as UTF-8, otherwise they are interpreted as Latin-1.hash
is a precomputed hash of the key string, or zero if it has not been precomputed. Returns a mortal scalar copy of the value associated with the key, or&PL_sv_placeholder
if there is no value associated with the key.
SV *cophh_fetch_pvn(const COPHH *cophh, const char *keypv, STRLEN keylen, U32 hash, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_fetch_pvn", but takes aNUL
-terminated literal string instead of a string/length pair, and no precomputed hash.
SV *cophh_fetch_pvs(const COPHH *cophh, const char *key, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_fetch_pvn", but takes a Perl scalar instead of a string/length pair.
SV *cophh_fetch_sv(const COPHH *cophh, SV *key, U32 hash, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Discard the cop hints hashcophh
, freeing all resources associated with it.
voidcophh_free(COPHH *cophh)
NOTE: this function 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()
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_store_pvn", but takes a nul-terminated string instead of a string/length pair.
COPHH *cophh_store_pv(const COPHH *cophh, const char *key, U32 hash, SV *value, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Stores a value, associated with a key, in the cop hints hashcophh
, and returns 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 key is specified bykeypv
andkeylen
. Ifflags
has theCOPHH_KEY_UTF8
bit set, the key octets are interpreted as UTF-8, otherwise they are interpreted as Latin-1.hash
is a precomputed hash of the key string, or zero if it has not been precomputed.
value
is the scalar value to store for this key.value
is copied by this function, which thus does not take ownership of any reference to it, and 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.
COPHH *cophh_store_pvn(COPHH *cophh, const char *keypv, STRLEN keylen, U32 hash, SV *value, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_store_pvn", but takes aNUL
-terminated literal string instead of a string/length pair, and no precomputed hash.
COPHH *cophh_store_pvs(const COPHH *cophh, const char *key, SV *value, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"cophh_store_pvn", but takes a Perl scalar instead of a string/length pair.
COPHH *cophh_store_sv(const COPHH *cophh, SV *key, U32 hash, SV *value, U32 flags)
Generates and returns a standard Perl hash representing the full set of hint entries in the copcop
.flags
is currently unused and must be zero.
HV *cop_hints_2hv(const COP *cop, U32 flags)
Like"cop_hints_fetch_pvn", but takes a nul-terminated string instead of a string/length pair.
SV *cop_hints_fetch_pv(const COP *cop, const char *key, U32 hash, U32 flags)
Look up the hint entry in the copcop
with the key specified bykeypv
andkeylen
. Ifflags
has theCOPHH_KEY_UTF8
bit set, the key octets are interpreted as UTF-8, otherwise they are interpreted as Latin-1.hash
is a precomputed hash of the key string, or zero if it has not been precomputed. Returns a mortal scalar copy of the value associated with the key, or&PL_sv_placeholder
if there is no value associated with the key.
SV *cop_hints_fetch_pvn(const COP *cop, const char *keypv, STRLEN keylen, U32 hash, U32 flags)
Like"cop_hints_fetch_pvn", but takes aNUL
-terminated literal string instead of a string/length pair, and no precomputed hash.
SV *cop_hints_fetch_pvs(const COP *cop, const char *key, U32 flags)
Like"cop_hints_fetch_pvn", but takes a Perl scalar instead of a string/length pair.
SV *cop_hints_fetch_sv(const COP *cop, SV *key, U32 hash, U32 flags)
Register a custom op. See"Custom Operators" in perlguts.
NOTE: this function must be explicitly called as Perl_custom_op_register with an aTHX_ parameter.
voidPerl_custom_op_register(pTHX_ Perl_ppaddr_t ppaddr, const XOP *xop)
Return the XOP structure for a given custom op. This macro should be considered internal toOP_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.
NOTE: this function must be explicitly called as Perl_custom_op_xop with an aTHX_ parameter.
const XOP * Perl_custom_op_xop(pTHX_ const OP *o)
Temporarily disable a member of the XOP, by clearing the appropriate flag.
voidXopDISABLE(XOP *xop, which)
Reenable a member of the XOP which has been disabled.
voidXopENABLE(XOP *xop, which)
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 onwhich
. This macro evaluates its arguments more than once. If you are usingPerl_custom_op_xop
to retreive aXOP *
from aOP *
, use the more efficient"XopENTRYCUSTOM" instead.
XopENTRY(XOP *xop, which)
Exactly likeXopENTRY(XopENTRY(Perl_custom_op_xop(aTHX_ o), which)
but more efficient. Thewhich
parameter is identical to"XopENTRY".
XopENTRYCUSTOM(const OP *o, which)
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.
voidXopENTRY_set(XOP *xop, which, value)
Return the XOP's flags.
U32XopFLAGS(XOP *xop)
This section documents functions to manipulate CVs which are code-values, or subroutines. For more information, seeperlguts.
The XSUB-writer's equivalent ofcaller(). The returnedPERL_CONTEXT
structure can be interrogated to find all the information returned to Perl bycaller
. Note that XSUBs don't get a stack frame, socaller_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 byDB::sub
, the return value will be the frame for the call toDB::sub
, since that has the correct line number/etc. for the call site. Ifdbcxp 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 )
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, seeperlguts.
This also has a special use with XS AUTOLOAD subs. See"Autoloading with XSUBs" in perlguts.
HV*CvSTASH(CV* cv)
Locate the CV corresponding to the currently executing sub or eval. Ifdb_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)
Usesstrlen
to get the length ofname
, then callsget_cvn_flags
.
NOTE: the perl_ form of this function is deprecated.
CV*get_cv(const char* name, I32 flags)
Returns the CV of the specified Perl subroutine.flags
are passed togv_fetchpvn_flags
. IfGV_ADD
is set and the Perl subroutine does not exist then it will be declared (which has the same effect as sayingsub name;
). IfGV_ADD
is not set and the subroutine does not exist then NULL is returned.
NOTE: the perl_ form of this function is deprecated.
CV*get_cvn_flags(const char* name, STRLEN len, I32 flags)
xsubpp
variables and internal functionsVariable which is setup byxsubpp
to indicate the stack base offset, used by theST
,XSprePUSH
andXSRETURN
macros. ThedMARK
macro must be called prior to setup theMARK
variable.
I32ax
Variable which is setup byxsubpp
to indicate the class name for a C++ XS constructor. This is always achar*
. See"THIS"
.
char*CLASS
Sets up theax
variable. This is usually handled automatically byxsubpp
by callingdXSARGS
.
dAX;
Sets up theax
variable and stack marker variablemark
. This is usually handled automatically byxsubpp
by callingdXSARGS
.
dAXMARK;
Sets up theitems
variable. This is usually handled automatically byxsubpp
by callingdXSARGS
.
dITEMS;
Sets up any variable needed by theUNDERBAR
macro. It used to definepadoff_du
, but it is currently a noop. However, it is strongly advised to still use it for ensuring past and future compatibility.
dUNDERBAR;
Sets up stack and mark pointers for an XSUB, callingdSP
anddMARK
. Sets up theax
anditems
variables by callingdAX
anddITEMS
. This is usually handled automatically byxsubpp
.
dXSARGS;
Sets up theix
variable for an XSUB which has aliases. This is usually handled automatically byxsubpp
.
dXSI32;
Variable which is setup byxsubpp
to indicate the number of items on the stack. See"Variable-length Parameter Lists" in perlxs.
I32items
Variable which is setup byxsubpp
to indicate which of an XSUB's aliases was used to invoke it. See"The ALIAS: Keyword" in perlxs.
I32ix
Variable which is setup byxsubpp
to hold the return value for an XSUB. This is always the proper type for the XSUB. See"The RETVAL Variable" in perlxs.
(whatever)RETVAL
Used to access elements on the XSUB's stack.
SV*ST(int ix)
Variable which is setup byxsubpp
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.
(whatever)THIS
The SV* corresponding to the$_
variable. Works even if there is a lexical$_
in scope.
Macro to declare an XSUB and its C parameter list. This is handled byxsubpp
. It is the same as using the more explicitXS_EXTERNAL
macro.
Macro to declare an XSUB and its C parameter list explicitly exporting the symbols.
Macro to declare an XSUB and its C parameter list without exporting the symbols. This is handled byxsubpp
and generally preferable over exporting the XSUB symbols unnecessarily.
Dumps the entire optree of the current program starting atPL_main_root
toSTDERR
. Also dumps the optrees for all visible subroutines inPL_defstash
.
voiddump_all()
Dumps the optrees for all visible subroutines instash
.
voiddump_packsubs(const HV* stash)
Dumps the optree starting at OPo
toSTDERR
.
voidop_dump(const OP *o)
Dumps the contents of an SV to theSTDERR
filehandle.
For an example of its output, seeDevel::Peek.
voidsv_dump(SV* sv)
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)
Escapes at most the firstcount
chars ofpv
and puts the results intodsv
such that the size of the escaped string will not exceedmax
chars and will not contain any incomplete escape sequences. The number of bytes escaped will be returned in theSTRLEN *escaped
parameter if it is not null. When thedsv
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 containsPERL_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 whenPERL_PV_ESCAPE_NOCLEAR
is set this will not occur.
IfPERL_PV_ESCAPE_UNI
is set then the input string is treated as UTF-8 ifPERL_PV_ESCAPE_UNI_DETECT
is set then the input string is scanned usingis_utf8_string()
to determine if it is UTF-8.
IfPERL_PV_ESCAPE_ALL
is set then all input chars will be output using\x01F1
style escapes, otherwise ifPERL_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, ifPERL_PV_ESCAPE_NOBACKSLASH
then all chars below 255 will be treated as printable and will be output as literals.
IfPERL_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.
IfPERL_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 bydsv
.
char*pv_escape(SV *dsv, char const * const str, const STRLEN count, const STRLEN max, STRLEN * const escaped, const U32 flags)
Converts a string into something presentable, handling escaping viapv_escape()
and supporting quoting and ellipses.
If thePERL_PV_PRETTY_QUOTE
flag is set then the result will be double quoted with any double quotes in the string escaped. Otherwise if thePERL_PV_PRETTY_LTGT
flag is set then the result be wrapped in angle brackets.
If thePERL_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.
Ifstart_color
is non-null then it will be inserted after the opening quote (if there is one) but before the escaped text. Ifend_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 bydsv
.
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)
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)
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.
Ifflags
has theCV_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)
Clear out all the active components of a CV. This can happen either by an explicitundef &foo
, or by the reference count going to zero. In the former case, we keep theCvOUTSIDE
pointer, so that any anonymous children can still follow the full lexical scope chain.
voidcv_undef(CV* cv)
Returns the global variable$_
.
SV *find_rundefsv()
DEPRECATED! It is planned to remove this function from a future release of Perl. Do not use it for new code; remove it from existing code.
Until the lexical$_
feature was removed, this function would find the position of the lexical$_
in the pad of the currently-executing function and returns the offset in the current pad, orNOT_IN_PAD
.
Now it always returnsNOT_IN_PAD
.
NOTE: the perl_ form of this function is deprecated.
PADOFFSET find_rundefsvoffset()
"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.
U32intro_my()
Loads 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". flags can be any ofPERL_LOADMOD_DENY
,PERL_LOADMOD_NOIMPORT
, orPERL_LOADMOD_IMPORT_OPS
(or 0 for no flags). ver, if specified and not NULL, provides version semantics similar touse Foo::Bar VERSION
. The optional trailing SV* arguments can be used to specify arguments to the module'simport()
method, similar touse Foo::Bar VERSION LIST
. They must be terminated with a finalNULL
pointer. Note that this list can only be omitted when thePERL_LOADMOD_NOIMPORT
flag has been used. Otherwise at least a singleNULL
pointer to designate the default import list is required.
The reference count for each specifiedSV*
parameter is decremented.
voidload_module(U32 flags, SV* name, SV* ver, ...)
NOTE: this function 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)
NOTE: this function 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 thePADNAMEt_OUTER
flag already set.
PADNAME * newPADNAMEouter(PADNAME *outer)
NOTE: this function 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)
Stub that provides thread hook for perl_destruct when there are no threads.
intnothreadhook()
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 functionfunc
is linked into the pad, and itsCvOUTSIDE
link to the outer scope is weakened to avoid a reference loop.
One reference count is stolen, so you may need to doSvREFCNT_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)
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, U32 flags, HV *typestash, HV *ourstash)
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. Iftypestash
is non-null, the name is for a typed lexical, and this identifies the type. Ifourstash
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 shadowingPADOFFSET pad_add_name_pvn(const char *namepv, STRLEN namelen, U32 flags, HV *typestash, HV *ourstash)
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)
NOTE: this function 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 storeSVf_READONLY constant shared between recursion levels
SVf_READONLY
has been supported here only since perl 5.20. To work with earlier versions as well, useSVf_READONLY|SVs_PADTMP
.SVf_READONLY
does not cause the SV in the pad slot to be marked read-only, but simply tellspad_alloc
that itwill 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)
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)
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, orNOT_IN_PAD
if no such lexical is in scope.
PADOFFSET pad_findmy_pvn(const char *namepv, STRLEN namelen, U32 flags)
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)
NOTE: this function 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)
NOTE: this function 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)
Set the value at offsetpo
in the current (compiling or executing) pad. Use the macroPAD_SETSV()
rather than calling this function directly.
voidpad_setsv(PADOFFSET po, SV *sv)
Get the value at offsetpo
in the current (compiling or executing) pad. Use macroPAD_SV
instead of calling this function directly.
SV *pad_sv(PADOFFSET po)
NOTE: this function 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 formatvoidpad_tidy(padtidy_type type)
Allocates a new Perl interpreter. Seeperlembed.
PerlInterpreter* perl_alloc()
Initializes a new Perl interpreter. Seeperlembed.
voidperl_construct(PerlInterpreter *my_perl)
Shuts down a Perl interpreter. Seeperlembed.
intperl_destruct(PerlInterpreter *my_perl)
Releases a Perl interpreter. Seeperlembed.
voidperl_free(PerlInterpreter *my_perl)
Tells a Perl interpreter to parse a Perl script. Seeperlembed.
intperl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit, int argc, char** argv, char** env)
Tells a Perl interpreter to run. Seeperlembed.
intperl_run(PerlInterpreter *my_perl)
Tells Perl torequire
the file named by the string argument. It is analogous to the Perl codeeval "require '$file'"
. It's even implemented that way; consider using load_module instead.
NOTE: the perl_ form of this function is deprecated.
voidrequire_pv(const char* pv)
Set up necessary local variables for exception handling. See"Exception Handling" in perlguts.
dXCPT;
Introduces a catch block. See"Exception Handling" in perlguts.
Rethrows a previously caught exception. See"Exception Handling" in perlguts.
XCPT_RETHROW;
Ends a try block. See"Exception Handling" in perlguts.
Starts a try block. See"Exception Handling" in perlguts.
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 local *foo = $someref;
works.
voidsave_gp(GV* gv, I32 empty)
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)
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)
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)
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)
Version object aware cmp. Both operands must already have been converted into version objects.
intvcmp(SV *lhv, SV *rhv)
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)
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)
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)
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)
Used to indicate list context. See"GIMME_V"
,"GIMME"
andperlcall.
Indicates that arguments returned from a callback should be discarded. Seeperlcall.
Used to force a Perleval
wrapper around a callback. Seeperlcall.
A backward-compatible version ofGIMME_V
which can only returnG_SCALAR
orG_ARRAY
; in a void context, it returnsG_SCALAR
. Deprecated. UseGIMME_V
instead.
U32GIMME
The XSUB-writer's equivalent to Perl'swantarray
. ReturnsG_VOID
,G_SCALAR
orG_ARRAY
for void, scalar or list context, respectively. Seeperlcall for a usage example.
U32GIMME_V
Indicates that no arguments are being sent to a callback. Seeperlcall.
Used to indicate scalar context. See"GIMME_V"
,"GIMME"
, andperlcall.
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 toperl5-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.
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 insteadwrap 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".
NOTE: this function 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, andkeyword_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 returnKEYWORD_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 ofOP
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, orKEYWORD_PLUGIN_EXPR
if it is an expression. Note that a statement construct cannot be used inside an expression (except viado 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 ofPL_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. ThusPL_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 returnKEYWORD_PLUGIN_DECLINE
.
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 $foo, @foo, %foo.
GVs are usually found as values in stashes (symbol table hashes) where Perl stores its global variables.
Return the AV from the GV.
AV*GvAV(GV* gv)
Ifgv
is a typeglob whose subroutine entry is a constant sub eligible for inlining, orgv
is a placeholder reference that would be promoted to such a typeglob, then returns the value returned by the sub. Otherwise, returnsNULL
.
SV*gv_const_sv(GV* gv)
Return the CV from the GV.
CV*GvCV(GV* gv)
Like"gv_fetchmeth_pvn", but lacks a flags parameter.
GV*gv_fetchmeth(HV* stash, const char* name, STRLEN len, I32 level)
Returns the glob which contains the subroutine to call to invoke the method on thestash
. In fact in the presence of autoloading this may be the glob for "AUTOLOAD". In this case the corresponding variable$AUTOLOAD
is already setup.
The third parameter ofgv_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. Callinggv_fetchmethod
is equivalent to callinggv_fetchmethod_autoload
with a non-zeroautoload
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 asgv_fetchmeth
withlevel==0
. The warning against passing the GV returned bygv_fetchmeth
tocall_sv
applies equally to these functions.
GV*gv_fetchmethod_autoload(HV* stash, const char* name, I32 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)
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)
Returns the glob with the givenname
and a defined subroutine orNULL
. The glob lives in the givenstash
, or in the stashes accessible via@ISA
andUNIVERSAL::
.
The argumentlevel
should be either 0 or -1. Iflevel==0
, as a side-effect creates a glob with the givenname
in the givenstash
which in the case of success contains an alias for the subroutine, and sets up caching info for this glob.
The only significant values forflags
areGV_SUPER
andSVf_UTF8
.
GV_SUPER
indicates that we want to look up the method in the superclasses of thestash
.
The GV returned fromgv_fetchmeth
may be a method cache entry, which is not visible to Perl code. So when callingcall_sv
, you should not use the GV directly; instead, you should use the method's CV, which can be obtained from the GV with theGvCV
macro.
GV*gv_fetchmeth_pvn(HV* stash, const char* name, STRLEN len, I32 level, U32 flags)
Same asgv_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 iflevel < 0
. For an autoloaded subroutine without a stub,GvCV()
of the result may be zero.
Currently, the only significant value forflags
isSVf_UTF8
.
GV*gv_fetchmeth_pvn_autoload(HV* stash, const char* name, STRLEN len, I32 level, U32 flags)
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)
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)
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)
Return the HV from the GV.
HV*GvHV(GV* gv)
The old form ofgv_init_pvn()
. It does not work with UTF-8 strings, as it has no flags parameter. If themulti
parameter is set, theGV_ADDMULTI
flag will be passed togv_init_pvn()
.
voidgv_init(GV* gv, HV* stash, const char* name, STRLEN len, int multi)
Same asgv_init_pvn()
, but takes a nul-terminated string for the name instead of separate char * and length parameters.
voidgv_init_pv(GV* gv, HV* stash, const char* name, U32 flags)
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 bySvSetSV
. Converting any scalar that isSvOK()
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
andlen
give the name. The name must be unqualified; that is, it must not include the package name. Ifgv
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 toSVf_UTF8
ifname
is a UTF-8 string, or the return value of SvUTF8(sv). It can also take theGV_ADDMULTI
flag, which means to pretend that the GV has been seen before (i.e., suppress "Used once" warnings).
voidgv_init_pvn(GV* gv, HV* stash, const char* name, STRLEN len, U32 flags)
Same asgv_init_pvn()
, but takes an SV * for the name instead of separate char * and length parameters.flags
is currently unused.
voidgv_init_sv(GV* gv, HV* stash, SV* namesv, U32 flags)
Returns a pointer to the stash for a specified package. Usesstrlen
to determine the length ofname
, then callsgv_stashpvn()
.
HV*gv_stashpv(const char* name, I32 flags)
Returns a pointer to the stash for a specified package. Thenamelen
parameter indicates the length of thename
, in bytes.flags
is passed togv_fetchpvn_flags()
, so if set toGV_ADD
then the package will be created if it does not already exist. If the package does not exist andflags
is 0 (or any other setting that does not create packages) thenNULL
is returned.
Flags may be one of:
GV_ADDSVf_UTF8GV_NOADD_NOINITGV_NOINITGV_NOEXPANDGV_ADDMG
The most important of which are probablyGV_ADD
andSVf_UTF8
.
Note, use ofgv_stashsv
instead ofgv_stashpvn
where possible is strongly recommended for performance reasons.
HV*gv_stashpvn(const char* name, U32 namelen, I32 flags)
Likegv_stashpvn
, but takes aNUL
-terminated literal string instead of a string/length pair.
HV*gv_stashpvs(const char* name, I32 create)
Returns a pointer to the stash for a specified package. See"gv_stashpvn"
.
Note this interface is strongly preferred overgv_stashpvn
for performance reasons.
HV*gv_stashsv(SV* sv, I32 flags)
Return the SV from the GV.
SV*GvSV(GV* gv)
SetsPL_defoutgv
, the default file handle for output, to the passed in typeglob. AsPL_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 thatPL_defoutgv
points to is decreased by one.
voidsetdefout(GV* gv)
Null AV pointer.
(deprecated - use(AV *)NULL
instead)
Null character pointer. (No longer available whenPERL_CORE
is defined.)
Null CV pointer.
(deprecated - use(CV *)NULL
instead)
Null HV pointer.
(deprecated - use(HV *)NULL
instead)
Null SV pointer. (No longer available whenPERL_CORE
is defined.)
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.
NOTE: this function is experimental and may change or be removed without notice.
Returns the label attached to a cop. The flags pointer may be set toSVf_UTF8
or 0.
const char * cop_fetch_label(COP *const cop, STRLEN *len, U32 *flags)
NOTE: this function is experimental and may change or be removed without notice.
Save a label into acop_hints_hash
. You need to set flags toSVf_UTF8
for a UTF-8 label.
voidcop_store_label(COP *const cop, const char *label, STRLEN len, U32 flags)
Returns the HV of the specified Perl hash.flags
are passed togv_fetchpv
. IfGV_ADD
is set and the Perl variable does not exist then it will be created. Ifflags
is zero and the variable does not exist thenNULL
is returned.
NOTE: the perl_ form of this function is deprecated.
HV*get_hv(const char *name, I32 flags)
This flag, used in the length slot of hash entries and magic structures, specifies the structure contains anSV*
pointer where achar*
pointer is to be expected. (For information only--not to be used).
Returns the computed hash stored in the hash entry.
U32HeHASH(HE* he)
Returns the actual pointer stored in the key slot of the hash entry. The pointer may be eitherchar*
orSV*
, depending on the value ofHeKLEN()
. Can be assigned to. TheHePV()
orHeSVKEY()
macros are usually preferable for finding the value of a key.
void*HeKEY(HE* he)
If this is negative, and amounts toHEf_SVKEY
, it indicates the entry holds anSV*
key. Otherwise, holds the actual length of the key. Can be assigned to. TheHePV()
macro is usually preferable for finding key lengths.
STRLENHeKLEN(HE* he)
Returns the key slot of the hash entry as achar*
value, doing any necessary dereferencing of possiblySV*
keys. The length of the string is placed inlen
(this is a macro, so donot use&len
). If you do not care about what the length of the key is, you may use the global variablePL_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 usingstrlen()
or similar is not a good way to find the length of hash keys. This is very similar to theSvPV()
macro described elsewhere in this document. See also"HeUTF8"
.
If you are usingHePV
to get values to pass tonewSVpvn()
to create a new SV, you should consider usingnewSVhek(HeKEY_hek(he))
as it is more efficient.
char*HePV(HE* he, STRLEN len)
Returns the key as anSV*
, orNULL
if the hash entry does not contain anSV*
key.
SV*HeSVKEY(HE* he)
Returns the key as anSV*
. Will create and return a temporary mortalSV*
if the hash entry contains only achar*
key.
SV*HeSVKEY_force(HE* he)
Sets the key to a givenSV*
, taking care to set the appropriate flags to indicate the presence of anSV*
key, and returns the sameSV*
.
SV*HeSVKEY_set(HE* he, SV* sv)
Returns whether thechar *
value returned byHePV
is encoded in UTF-8, doing any necessary dereferencing of possiblySV*
keys. The value returned will be 0 or non-0, not necessarily 1 (or even a value with any low bits set), sodo not blindly assign this to abool
variable, asbool
may be a typedef forchar
.
U32HeUTF8(HE* he)
Returns the value slot (typeSV*
) stored in the hash entry. Can be assigned to.
SV *foo= HeVAL(hv); HeVAL(hv)= sv;SV*HeVAL(HE* he)
Check that a hash is in an internally consistent state.
voidhv_assert(HV *hv)
Frees the 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.
voidhv_clear(HV *hv)
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. SeeHash::Util::lock_keys()
for an example of its use.
voidhv_clear_placeholders(HV *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), orNULL
(interpreted as an empty hash). The content ofohv
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 *ohv)
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 ofklen
is the length of the key. Ifklen
is negative the key is assumed to be in UTF-8-encoded Unicode. Theflags
value will normally be zero; if set toG_DISCARD
thenNULL
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)
Deletes a key/value pair in the hash. The value SV is removed from the hash, made mortal, and returned to the caller. Theflags
value will normally be zero; if set toG_DISCARD
thenNULL
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)
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 toHvNAME
for use in MRO linearisations and isa caches.
char*HvENAME(HV* stash)
Returns the length of the stash's effective name.
STRLENHvENAMELEN(HV *stash)
Returns true if the effective name is in UTF-8 encoding.
unsigned char HvENAMEUTF8(HV *stash)
Returns a boolean indicating whether the specified hash key exists. The absolute value ofklen
is the length of the key. Ifklen
is negative the key is assumed to be in UTF-8-encoded Unicode.
boolhv_exists(HV *hv, const char *key, I32 klen)
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.
boolhv_exists_ent(HV *hv, SV *keysv, U32 hash)
Returns the SV which corresponds to the specified key in the hash. The absolute value ofklen
is the length of the key. Ifklen
is negative the key is assumed to be in UTF-8-encoded Unicode. Iflval
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. TheSV*
it points to can be assigned to. But always check that the return value is non-null before dereferencing it to anSV*
.
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)
Likehv_fetch
, but takes aNUL
-terminated literal string instead of a string/length pair.
SV**hv_fetchs(HV* tb, const char* key, I32 lval)
Returns the hash entry which corresponds to the specified key in the hash.hash
must be a valid precomputed hash number for the givenkey
, or 0 if you want the function to compute it. IFlval
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 whenhv
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)
Returns the number of hash buckets that happen to be in use. This function is wrapped by the macroHvFILL
.
Previously this value was always stored in the HV structure, which created an overhead on every hash (and pretty much every object) for something that was rarely used. Now we calculate it on demand the first time that it is needed, and cache it if that calculation is going to be costly to repeat. The cached value is updated by insertions and deletions, but (currently) discarded if the hash is split.
STRLENhv_fill(HV *const hv)
Prepares a starting point to traverse a hash table. Returns the number of keys in the hash (i.e. the same asHvUSEDKEYS(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 macroHvFILL(hv)
.
I32hv_iterinit(HV *hv)
Returns the key from the current position of the hash iterator. See"hv_iterinit"
.
char*hv_iterkey(HE* entry, I32* retlen)
Returns the key as anSV*
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)
Returns entries from a hash iterator. See"hv_iterinit"
.
You may callhv_delete
orhv_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 tohv_iternext
, so you must not discard your iterator immediately else the entry will leak - callhv_iternext
to trigger the resource deallocation.
HE*hv_iternext(HV *hv)
Performs anhv_iternext
,hv_iterkey
, andhv_iterval
in one operation.
SV*hv_iternextsv(HV *hv, char **key, I32 *retlen)
NOTE: this function is experimental and may change or be removed without notice.
Returns entries from a hash iterator. See"hv_iterinit"
and"hv_iternext"
. Theflags
value will normally be zero; ifHV_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)
Returns the value from the current position of the hash iterator. See"hv_iterkey"
.
SV*hv_iterval(HV *hv, HE *entry)
Adds magic to a hash. See"sv_magic"
.
voidhv_magic(HV *hv, GV *gv, int how)
Returns the package name of a stash, orNULL
ifstash
isn't a stash. See"SvSTASH"
,"CvSTASH"
.
char*HvNAME(HV* stash)
Returns the length of the stash's name.
STRLENHvNAMELEN(HV *stash)
Returns true if the name is in UTF-8 encoding.
unsigned char HvNAMEUTF8(HV *stash)
Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
SV*hv_scalar(HV *hv)
Stores an SV in a hash. The hash key is specified askey
and the absolute value ofklen
is the length of the key. Ifklen
is negative the key is assumed to be in UTF-8-encoded Unicode. Thehash
parameter is the precomputed hash value; if it is zero then Perl will compute it.
The return value will beNULL
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 originalSV*
. Note that the caller is responsible for suitably incrementing the reference count ofval
before the call, and decrementing it if the function returnedNULL
. Effectively a successfulhv_store
takes ownership of one reference toval
. 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 tohv_store_ent
, and does not create a temporary SV for the key, so if your key data is not already in SV form then usehv_store
in preference tohv_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)
Likehv_store
, but takes aNUL
-terminated literal string instead of a string/length pair and omits the hash parameter.
SV**hv_stores(HV* tb, const char* key, NULLOK SV* val)
Storesval
in a hash. The hash key is specified askey
. Thehash
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 beNULL
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 theHe?
macros described here. Note that the caller is responsible for suitably incrementing the reference count ofval
before the call, and decrementing it if the function returned NULL. Effectively a successfulhv_store_ent
takes ownership of one reference toval
. 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 thathv_store_ent
only reads thekey
; unlikeval
it does not take ownership of it, so maintaining the correct reference count onkey
is entirely the caller's responsibility.hv_store
is not implemented as a call tohv_store_ent
, and does not create a temporary SV for the key, so if your key data is not already in SV form then usehv_store
in preference tohv_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)
Undefines the hash. The XS equivalent ofundef(%hash)
.
As well as freeing all the elements of the hash (likehv_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.
voidhv_undef(HV *hv)
Creates a new HV. The reference count is set to 1.
HV*newHV()
These functions provide convenient and thread-safe means of manipulating hook variables.
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, andold_checker_p
points to the storage location where a pointer to the next function in the chain will be stored. The value ofnew_pointer
is written into the"PL_check" array, while the value previously stored there is written to*old_checker_p
.
The function should be defined like this:
static OP *new_checker(pTHX_ OP *op) { ... }
It is intended to be called in this manner:
new_checker(aTHX_ op)
old_checker_p
should be defined like this:
static Perl_check_t 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 markedstatic
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 bynew_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 beforenew_checker
is called. Ifnew_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
.
If you want to influence compilation of calls to a specific subroutine, then use"cv_set_call_checker" rather than hooking checking of allentersub
ops.
voidwrap_op_checker(Optype opcode, Perl_check_t new_checker, Perl_check_t *old_checker_p)
This is the lower layer of the Perl parser, managing characters and tokens.
NOTE: this function 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 theSvUTF8
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 actualSvUTF8
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 itsSvUTF8
flag is off, but the octets should be interpreted as UTF-8 if theuse utf8
pragma is in effect. During a string eval, however, the scalar may have theSvUTF8
flag on, and in this case its octets should be interpreted as UTF-8 unless theuse bytes
pragma is in effect. This logic may change in the future; use this function instead of implementing the logic yourself.
boollex_bufutf8()
NOTE: this function is experimental and may change or be removed without notice.
Discards the first part of the"PL_parser->linestr" buffer, up toptr
. 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.
voidlex_discard_to(char *ptr)
NOTE: this function is experimental and may change or be removed without notice.
Reallocates the lexer buffer ("PL_parser->linestr") to accommodate at leastlen
octets (including terminatingNUL
). 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 useSvGROW
orsv_grow
directly onPL_parser->linestr
; this function updates all of the lexer's variables that point directly into the buffer.
char *lex_grow_linestr(STRLEN len)
NOTE: this function 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. Ifflags
has theLEX_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.
boollex_next_chunk(U32 flags)
NOTE: this function 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 ifflags
has theLEX_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.
I32lex_peek_unichar(U32 flags)
NOTE: this function 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 ifflags
has theLEX_KEEP_PREVIOUS
bit set, then the current chunk will not be discarded.
voidlex_read_space(U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Consume text in the lexer buffer, from"PL_parser->bufptr" up toptr
. This advances"PL_parser->bufptr" to matchptr
, 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".
voidlex_read_to(char *ptr)
NOTE: this function 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 ifflags
has theLEX_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.
I32lex_read_unichar(U32 flags)
NOTE: this function 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 fromline
andrsfp
.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 ofline
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 inline
comes first and must consist of complete lines of input, andrsfp
supplies the remainder of the source.
Theflags
parameter is reserved for future use. Currently it is only used by perl internally, so extensions should always pass zero.
voidlex_start(SV *line, PerlIO *rsfp, U32 flags)
NOTE: this function 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 atpv
and continuing to the first nul. These octets are interpreted as either UTF-8 or Latin-1, according to whether theLEX_STUFF_UTF8
flag is set inflags
. 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.
voidlex_stuff_pv(const char *pv, U32 flags)
NOTE: this function 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 bylen
octets starting atpv
. These octets are interpreted as either UTF-8 or Latin-1, according to whether theLEX_STUFF_UTF8
flag is set inflags
. 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.
voidlex_stuff_pvn(const char *pv, STRLEN len, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Like"lex_stuff_pvn", but takes aNUL
-terminated literal string instead of a string/length pair.
voidlex_stuff_pvs(const char *pv, U32 flags)
NOTE: this function 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 ofsv
. 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.
voidlex_stuff_sv(SV *sv, U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
Discards text about to be lexed, from"PL_parser->bufptr" up toptr
. Text followingptr
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".
voidlex_unstuff(char *ptr)
NOTE: this function 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. Ifflags
has thePARSE_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)
NOTE: this function 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 anextstate
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.
Theflags
parameter is reserved for future use, and must always be zero.
OP *parse_barestmt(U32 flags)
NOTE: this function 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, somy
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 alineseq
list, includingnextstate
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.
Theflags
parameter is reserved for future use, and must always be zero.
OP *parse_block(U32 flags)
NOTE: this function 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 asor
. 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. Ifflags
has thePARSE_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)
NOTE: this function 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 anextstate
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.
Theflags
parameter is reserved for future use, and must always be zero.
OP *parse_fullstmt(U32 flags)
NOTE: this function 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. Ifflags
has thePARSE_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)
NOTE: this function 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 asor
or by something that would normally terminate an expression such as semicolon. Ifflags
has thePARSE_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)
NOTE: this function 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 alineseq
list, normally includingnextstate
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.
Theflags
parameter is reserved for future use, and must always be zero.
OP *parse_stmtseq(U32 flags)
NOTE: this function 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. Ifflags
has thePARSE_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)
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 ofPL_parser
have their own documentation.
NOTE: this function 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 toSvPVX(PL_parser->linestr) + SvCUR(PL_parser->linestr)
. ANUL
character (zero octet) is always located at the end of the buffer, and does not count as part of the buffer's contents.
NOTE: this function 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 bySvPVX("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".
NOTE: this function 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.
NOTE: this function 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 whichSvPOK
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 variouschar*
pointers to things in thePL_parser->linestr
buffer. IfPL_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 theSvUTF8
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.
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.
voidDECLARATION_FOR_LC_NUMERIC_MANIPULATION
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 theLC_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 twoSTORE
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(); ... }voidRESTORE_LC_NUMERIC()
This is used by XS code that that isLC_NUMERIC
locale-aware to force the locale for categoryLC_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 functionsetlocale(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.
voidSTORE_LC_NUMERIC_FORCE_TO_UNDERLYING()
This is used to help wrap XS or C code that that isLC_NUMERIC
locale-aware. This locale category is generally kept set to the C locale by Perl for backwards compatibility, and because most XS code that reads floating point values can cope only with the decimal radix character being a dot.
This macro makes sure the currentLC_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 ause locale
; or to ignore locale if the call is instead from outside such scope.
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(); ... }voidSTORE_LC_NUMERIC_SET_TO_NEEDED()
Changing the program's locale should be avoided by XS code. Nevertheless, certain non-Perl libraries called from XS, such asGtk
do so. When this happens, Perl needs to be told that the locale has changed. Use this function to do so, before returning to Perl.
voidsync_locale()
Clear something magical that the SV represents. See"sv_magic"
.
intmg_clear(SV* sv)
Copies the magic from one SV to another. See"sv_magic"
.
intmg_copy(SV *sv, SV *nsv, const char *key, I32 klen)
Finds the magic pointer fortype
matching the SV. See"sv_magic"
.
MAGIC*mg_find(const SV* sv, int type)
Finds the magic pointer oftype
with the givenvtbl
for theSV
. See"sv_magicext"
.
MAGIC*mg_findext(const SV* sv, int type, const MGVTBL *vtbl)
Free any magic storage used by the SV. See"sv_magic"
.
intmg_free(SV* sv)
Remove any magic of typehow
from the SVsv
. See"sv_magic".
voidmg_free_type(SV *sv, int how)
Do magic before a value is retrieved from the SV. The type of SV must be >=SVt_PVMG
. See"sv_magic"
.
intmg_get(SV* sv)
DEPRECATED! It is planned to remove this function 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 onsv
. 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 assumessv
is aPVMG
or higher. Usesv_len()
instead.
U32mg_length(SV* sv)
Turns on the magical status of an SV. See"sv_magic"
.
voidmg_magical(SV* sv)
Do magic after a value is assigned to the SV. See"sv_magic"
.
intmg_set(SV* sv)
Invokesmg_get
on an SV if it has 'get' magic. For example, this will callFETCH
on a tied variable. This macro evaluates its argument more than once.
voidSvGETMAGIC(SV* sv)
Arranges for a mutual exclusion lock to be obtained onsv
if a suitable module has been loaded.
voidSvLOCK(SV* sv)
Invokesmg_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 callsSTORE
). This macro evaluates its argument more than once.
voidSvSETMAGIC(SV* sv)
LikeSvSetSV
, but does any set magic required afterwards.
voidSvSetMagicSV(SV* dsv, SV* ssv)
LikeSvSetSV_nosteal
, but does any set magic required afterwards.
voidSvSetMagicSV_nosteal(SV* dsv, SV* ssv)
Callssv_setsv
ifdsv
is not the same asssv
. May evaluate arguments more than once. Does not handle 'set' magic on the destination SV.
voidSvSetSV(SV* dsv, SV* ssv)
Calls a non-destructive version ofsv_setsv
ifdsv
is not the same asssv
. May evaluate arguments more than once.
voidSvSetSV_nosteal(SV* dsv, SV* ssv)
Arranges forsv
to be shared between threads if a suitable module has been loaded.
voidSvSHARE(SV* sv)
Releases a mutual exclusion lock onsv
if a suitable module has been loaded.
voidSvUNLOCK(SV* sv)
The XSUB-writer's interface to the Cmemcpy
function. Thesrc
is the source,dest
is the destination,nitems
is the number of items, andtype
is the type. May fail on overlapping copies. See also"Move"
.
voidCopy(void* src, void* dest, int nitems, type)
LikeCopy
but returnsdest
. Useful for encouraging compilers to tail-call optimise.
void *CopyD(void* src, void* dest, int nitems, type)
The XSUB-writer's interface to the Cmemmove
function. Thesrc
is the source,dest
is the destination,nitems
is the number of items, andtype
is the type. Can do overlapping moves. See also"Copy"
.
voidMove(void* src, void* dest, int nitems, type)
LikeMove
but returnsdest
. Useful for encouraging compilers to tail-call optimise.
void *MoveD(void* src, void* dest, int nitems, type)
The XSUB-writer's interface to the Cmalloc
function.
Memory obtained by this shouldONLY 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.
voidNewx(void* ptr, int nitems, type)
The XSUB-writer's interface to the Cmalloc
function, with cast. See also"Newx"
.
Memory obtained by this shouldONLY be freed with"Safefree".
voidNewxc(void* ptr, int nitems, type, cast)
The XSUB-writer's interface to the Cmalloc
function. The allocated memory is zeroed withmemzero
. See also"Newx"
.
Memory obtained by this shouldONLY be freed with"Safefree".
voidNewxz(void* ptr, int nitems, type)
PoisonWith(0xEF) for catching access to freed memory.
voidPoison(void* dest, int nitems, type)
PoisonWith(0xEF) for catching access to freed memory.
voidPoisonFree(void* dest, int nitems, type)
PoisonWith(0xAB) for catching access to allocated but uninitialized memory.
voidPoisonNew(void* dest, int nitems, type)
Fill up memory with a byte pattern (a byte repeated over and over again) that hopefully catches attempts to access uninitialized memory.
voidPoisonWith(void* dest, int nitems, type, U8 byte)
The XSUB-writer's interface to the Crealloc
function.
Memory obtained by this shouldONLY be freed with"Safefree".
voidRenew(void* ptr, int nitems, type)
The XSUB-writer's interface to the Crealloc
function, with cast.
Memory obtained by this shouldONLY be freed with"Safefree".
voidRenewc(void* ptr, int nitems, type, cast)
The XSUB-writer's interface to the Cfree
function.
This shouldONLY be used on memory obtained using"Newx" and friends.
voidSafefree(void* ptr)
Perl's version ofstrdup()
. Returns a pointer to a newly allocated string which is a duplicate ofpv
. The size of the string is determined bystrlen()
, which means it may not contain embeddedNUL
characters and must have a trailingNUL
. The memory allocated for the new string can be freed with theSafefree()
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"savesharedpv"
.
char*savepv(const char* pv)
Perl's version of whatstrndup()
would be if it existed. Returns a pointer to a newly allocated string which is a duplicate of the firstlen
bytes frompv
, plus a trailingNUL
byte. The memory allocated for the new string can be freed with theSafefree()
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, I32 len)
Likesavepvn
, but takes aNUL
-terminated literal string instead of a string/length pair.
char*savepvs(const char* s)
A version ofsavepv()
which allocates the duplicate string in memory which is shared between threads.
char*savesharedpv(const char* pv)
A version ofsavepvn()
which allocates the duplicate string in memory which is shared between threads. (With the specific difference that aNULL
pointer is not acceptable)
char*savesharedpvn(const char *const pv, const STRLEN len)
A version ofsavepvs()
which allocates the duplicate string in memory which is shared between threads.
char*savesharedpvs(const char* s)
A version ofsavesharedpv()
which allocates the duplicate string in memory which is shared between threads.
char*savesharedsvpv(SV *sv)
A version ofsavepv()
/savepvn()
which gets the string to duplicate from the passed in SV usingSvPV()
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)
This is an architecture-independent macro to copy one structure to another.
voidStructCopy(type *src, type *dest, type)
The XSUB-writer's interface to the Cmemzero
function. Thedest
is the destination,nitems
is the number of items, andtype
is the type.
voidZero(void* dest, int nitems, type)
LikeZero
but returns dest. Useful for encouraging compilers to tail-call optimise.
void *ZeroD(void* dest, int nitems, type)
Dumps the C backtrace to the givenfp
.
Returns true if a backtrace could be retrieved, false if not.
booldump_c_backtrace(PerlIO* fp, int max_depth, int skip)
Analyses the string in order to make fast searches on it usingfbm_instr()
-- the Boyer-Moore algorithm.
voidfbm_compile(SV* sv, U32 flags)
Returns the location of the SV in the string delimited bybig
andbigend
(bigend
) is the char following the last char). It returnsNULL
if the string can't be found. Thesv
does not have to befbm_compiled
, but the search will not be as fast then.
char*fbm_instr(unsigned char* big, unsigned char* bigend, SV* littlestr, U32 flags)
Returns true if the leadinglen
bytes of the stringss1
ands2
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.
I32foldEQ(const char* a, const char* b, I32 len)
Returns true if the leadinglen
bytes of the stringss1
ands2
are the same case-insensitively in the current locale; false otherwise.
I32foldEQ_locale(const char* a, const char* b, I32 len)
Takes a sprintf-style format pattern and conventional (non-SV) arguments and returns 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);
Uses a single 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).
char*form(const char* pat, ...)
Fillsv
with current working directory
intgetcwd_sv(SV* sv)
Returns a SV containing a dump ofdepth
frames of the call stack, skipping theskip
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 inS_parse_body
, and the :offset (might be missing) tells how much inside theS_parse_body
the program counter was.
Theutil.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)
This is a synonym for(! foldEQ())
I32ibcmp(const char* a, const char* b, I32 len)
This is a synonym for(! foldEQ_locale())
I32ibcmp_locale(const char* a, const char* b, I32 len)
Test that the givenpv
doesn't contain any internalNUL
characters. If it does, seterrno
toENOENT
, optionally warn, and return FALSE.
Return TRUE if the name is safe.
Used by theIS_SAFE_SYSCALL()
macro.
boolis_safe_syscall(const char *pv, STRLEN len, const char *what, const char *op_name)
Test two buffers (which may contain embeddedNUL
characters, to see if they are equal. Thelen
parameter indicates the number of bytes to compare. Returns zero if equal, or non-zero if non-equal.
boolmemEQ(char* s1, char* s2, STRLEN len)
Test two buffers (which may contain embeddedNUL
characters, to see if they are not equal. Thelen
parameter indicates the number of bytes to compare. Returns zero if non-equal, or non-zero if equal.
boolmemNE(char* s1, char* s2, STRLEN len)
Take a sprintf-style format pattern and 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".
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 *mess(const char *pat, ...)
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 asat 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. Ifconsume
is true, then the function is permitted (but not required) to modify and returnbasemsg
instead of allocating a new SV.
SV *mess_sv(SV *basemsg, bool consume)
The C librarysnprintf
functionality, if available and standards-compliant (usesvsnprintf
, actually). However, if thevsnprintf
is not available, will unfortunately use the unsafevsprintf
which can overrun the buffer (there is an overrun check, but that may be too late). Consider usingsv_vcatpvf
instead, or gettingvsnprintf
.
intmy_snprintf(char *buffer, const Size_t len, const char *format, ...)
The C librarysprintf
, wrapped if necessary, to ensure that it will return the length of the string written to the buffer. Only rare pre-ANSI systems need the wrapper function - usually this is a direct call tosprintf
.
intmy_sprintf(char *buffer, const char *pat, ...)
The C librarystrlcat
if available, or a Perl implementation of it. This operates on CNUL
-terminated strings.
my_strlcat()
appends stringsrc
to the end ofdst
. It will append at mostsize - strlen(dst) - 1
characters. It will thenNUL
-terminate, unlesssize
is 0 or the originaldst
string was longer thansize
(in practice this should not happen as it means that eithersize
is incorrect or thatdst
is not a properNUL
-terminated string).
Note thatsize
is the full size of the destination buffer and the result is guaranteed to beNUL
-terminated if there is room. Note that room for theNUL
should be included insize
.
Size_tmy_strlcat(char *dst, const char *src, Size_t size)
The C librarystrlcpy
if available, or a Perl implementation of it. This operates on CNUL
-terminated strings.
my_strlcpy()
copies up tosize - 1
characters from the stringsrc
todst
,NUL
-terminating the result ifsize
is not 0.
Size_tmy_strlcpy(char *dst, const char *src, Size_t size)
The C libraryvsnprintf
if available and standards-compliant. However, if if thevsnprintf
is not available, will unfortunately use the unsafevsprintf
which can overrun the buffer (there is an overrun check, but that may be too late). Consider usingsv_vcatpvf
instead, or gettingvsnprintf
.
intmy_vsnprintf(char *buffer, const Size_t len, const char *format, va_list ap)
Find the first (leftmost) occurrence of a sequence of bytes within another sequence. This is the Perl version ofstrstr()
, extended to handle arbitrary sequences, potentially containing embeddedNUL
characters (NUL
is what the initialn
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 returnsNULL
if there is no occurrence oflittle
withinbig
. Iflittle
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(char * big, char * bigend, char * little, char * little_end)
Provides system-specific tune up of the C runtime environment necessary to run Perl interpreters. This should be called only once, before creating any Perl interpreters.
voidPERL_SYS_INIT(int *argc, char*** argv)
Provides system-specific tune up of the C runtime environment necessary to run Perl interpreters. This should be called only once, before creating any Perl interpreters.
voidPERL_SYS_INIT3(int *argc, char*** argv, char*** env)
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.
voidPERL_SYS_TERM()
quadmath_format_needed()
returns true if theformat
string seems to contain at least one non-Q-prefixed%[efgaEFGA]
format specifier, or returns false otherwise.
The format specifier detection is not complete printf-syntax detection, but it should catch most common cases.
If true is returned, those argumentsshould in theory be processed withquadmath_snprintf()
, but in case there is more than one such format specifier (see"quadmath_format_single"), and if there is anything else beyond that one (even just a single byte), theycannot be processed becausequadmath_snprintf()
is very strict, accepting only one format spec, and nothing else. In this case, the code should probably fail.
boolquadmath_format_needed(const char* format)
quadmath_snprintf()
is very strict about itsformat
string and will fail, returning -1, if the format is invalid. It accepts exactly one format spec.
quadmath_format_single()
checks that the intended single spec looks sane: begins with%
, has only one%
, ends with[efgaEFGA]
, and hasQ
before it. This is not a full "printf syntax check", just the basics.
Returns the format if it is valid, NULL if not.
quadmath_format_single()
can and will actually patch in the missingQ
, if necessary. In this case it will return the modified copy of the format,which the caller will need to free.
See also"quadmath_format_needed".
const char* quadmath_format_single(const char* format)
Returns the value of an ASCII-range hex digit and advances the string pointer. Behaviour is only well defined when isXDIGIT(*str) is true.
U8READ_XDIGIT(char str*)
Like"ninstr"
, but instead finds the final (rightmost) occurrence of a sequence of bytes within another sequence, returningNULL
if there is no such occurrence.
char *rninstr(char * big, char * bigend, char * little, char * little_end)
Test twoNUL
-terminated strings to see if they are equal. Returns true or false.
boolstrEQ(char* s1, char* s2)
Test twoNUL
-terminated strings to see if the first,s1
, is greater than or equal to the second,s2
. Returns true or false.
boolstrGE(char* s1, char* s2)
Test twoNUL
-terminated strings to see if the first,s1
, is greater than the second,s2
. Returns true or false.
boolstrGT(char* s1, char* s2)
Test twoNUL
-terminated strings to see if the first,s1
, is less than or equal to the second,s2
. Returns true or false.
boolstrLE(char* s1, char* s2)
Test twoNUL
-terminated strings to see if the first,s1
, is less than the second,s2
. Returns true or false.
boolstrLT(char* s1, char* s2)
Test twoNUL
-terminated strings to see if they are different. Returns true or false.
boolstrNE(char* s1, char* s2)
Test twoNUL
-terminated strings to see if they are equal. Thelen
parameter indicates the number of bytes to compare. Returns true or false. (A wrapper forstrncmp
).
boolstrnEQ(char* s1, char* s2, STRLEN len)
Test twoNUL
-terminated strings to see if they are different. Thelen
parameter indicates the number of bytes to compare. Returns true or false. (A wrapper forstrncmp
).
boolstrnNE(char* s1, char* s2, STRLEN len)
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 aNULL
function pointer and because it could potentially warn under some level of strict-ness.
boolsv_destroyable(SV *sv)
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 aNULL
function pointer and because it could potentially warn under some level of strict-ness.
voidsv_nosharing(SV *sv)
pat
andargs
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)
These functions are related to the method resolution order of perl classes
Returns the mro linearisation for the given stash. By default, this will be whatevermro_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 forSvREFCNT_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)
Invalidates method caching on any child classes of the given stash, so that they might notice the changes in this one.
Ideally, all instances ofPL_sub_generation++
in perl source outside ofmro.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 (likeconstant.pm does).
This same method is available from pure perl via,mro::method_changed_in(classname)
.
voidmro_method_changed_in(HV* stash)
Registers a custom mro plugin. Seeperlmroapi for details.
voidmro_register(const struct mro_alg *mro)
Declare local variables for a multicall. See"LIGHTWEIGHT CALLBACKS" in perlcall.
dMULTICALL;
Make a lightweight callback. See"LIGHTWEIGHT CALLBACKS" in perlcall.
MULTICALL;
Closing bracket for a lightweight callback. See"LIGHTWEIGHT CALLBACKS" in perlcall.
POP_MULTICALL;
Opening bracket for a lightweight callback. See"LIGHTWEIGHT CALLBACKS" in perlcall.
PUSH_MULTICALL;
converts a string representing a binary number to numeric form.
On entrystart
and*len
give the string to scan,*flags
gives conversion flags, andresult
should beNULL
or a pointer to an NV. The scan stops at the end of the string, or the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT
is set in*flags
, encountering an invalid character will also trigger a warning. On return*len
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
returnsUV_MAX
, setsPERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes the value to*result
(or the value is discarded ifresult
is NULL).
The binary number may optionally be prefixed with"0b"
or"b"
unlessPERL_SCAN_DISALLOW_PREFIX
is set in*flags
on entry. IfPERL_SCAN_ALLOW_UNDERSCORES
is set in*flags
then the binary number may use"_"
characters to separate digits.
UVgrok_bin(const char* start, STRLEN* len_p, I32* flags, NV *result)
converts a string representing a hex number to numeric form.
On entrystart
and*len_p
give the string to scan,*flags
gives conversion flags, andresult
should beNULL
or a pointer to an NV. The scan stops at the end of the string, or the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT
is set in*flags
, encountering an invalid character will also trigger a warning. On return*len
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
returnsUV_MAX
, setsPERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes the value to*result
(or the value is discarded ifresult
isNULL
).
The hex number may optionally be prefixed with"0x"
or"x"
unlessPERL_SCAN_DISALLOW_PREFIX
is set in*flags
on entry. IfPERL_SCAN_ALLOW_UNDERSCORES
is set in*flags
then the hex number may use"_"
characters to separate digits.
UVgrok_hex(const char* start, STRLEN* len_p, I32* flags, NV *result)
Helper forgrok_number()
, accepts various ways of spelling "infinity" or "not a number", and returns one of the following flag combinations:
IS_NUMBER_INFINITEIS_NUMBER_NANIS_NUMBER_INFINITE | IS_NUMBER_NEGIS_NUMBER_NAN | IS_NUMBER_NEG0
possibly |-ed withIS_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.
intgrok_infnan(const char** sp, const char *send)
Identical togrok_number_flags()
withflags
set to zero.
intgrok_number(const char *pv, STRLEN len, UV *valuep)
Recognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise it is a bit-ORed combination ofIS_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 thoughIS_NUMBER_IN_UV
is not set on return. Ifvaluep
isNULL
,IS_NUMBER_IN_UV
will be set for the same cases as whenvaluep
is non-NULL
, but no actual assignment (or SEGV) will occur.
IS_NUMBER_NOT_INT
will be set withIS_NUMBER_IN_UV
if trailing decimals were seen (in which case*valuep
gives the true value truncated to an integer), andIS_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 onlyPERL_SCAN_TRAILING
, which allows for trailing non-numeric text on an otherwise successfulgrok, settingIS_NUMBER_TRAILING
on the result.
intgrok_number_flags(const char *pv, STRLEN len, UV *valuep, U32 flags)
Scan and skip for a numeric decimal separator (radix).
boolgrok_numeric_radix(const char **sp, const char *send)
converts a string representing an octal number to numeric form.
On entrystart
and*len
give the string to scan,*flags
gives conversion flags, andresult
should beNULL
or a pointer to an NV. The scan stops at the end of the string, or the first invalid character. UnlessPERL_SCAN_SILENT_ILLDIGIT
is set in*flags
, encountering an 8 or 9 will also trigger a warning. On return*len
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
returnsUV_MAX
, setsPERL_SCAN_GREATER_THAN_UV_MAX
in the output flags, and writes the value to*result
(or the value is discarded ifresult
isNULL
).
IfPERL_SCAN_ALLOW_UNDERSCORES
is set in*flags
then the octal number may use"_"
characters to separate digits.
UVgrok_oct(const char* start, STRLEN* len_p, I32* flags, NV *result)
Perl_isinfnan()
is utility function that returns true if the NV argument is either an infinity or aNaN
, false otherwise. To test in more detail, usePerl_isinf()
andPerl_isnan()
.
This is also the logical inverse of Perl_isfinite().
boolisinfnan(NV nv)
NOTE: this function 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.
IfConfigure detects this system has asignbit()
that will work with our NVs, then we just use it via the#define
inperl.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 asignbit()
function or macro that doesn't happen to work with our particular choice of NVs. We shouldn't just re-#define
signbit
asPerl_signbit
and expect the standard system headers to be happy. Also, this is a no-context function (nopTHX_
) becausePerl_signbit()
is usually re-#defined
inperl.h as a simple macro call to the system'ssignbit()
. Users should just always callPerl_signbit()
.
intPerl_signbit(NV f)
For backwards compatibility. Usegrok_bin
instead.
NVscan_bin(const char* start, STRLEN len, STRLEN* retlen)
For backwards compatibility. Usegrok_hex
instead.
NVscan_hex(const char* start, STRLEN len, STRLEN* retlen)
For backwards compatibility. Usegrok_oct
instead.
NVscan_oct(const char* start, STRLEN len, STRLEN* retlen)
Some of these are also deprecated. You can exclude these from your compiled Perl by adding this option to Configure:-Accflags='-DNO_MATHOMS'
Return the description of a given custom op. This was once used by theOP_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)
Return the name for a given custom op. This was once used by theOP_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)
GV*gv_fetchmethod(HV* stash, const char* name)
DEPRECATED! It is planned to remove this function 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.
STRLENis_utf8_char(const U8 *s)
This is identical to the macro"isUTF8_CHAR".
STRLENis_utf8_char_buf(const U8 *buf, const U8 *buf_end)
The engine implementingpack()
Perl function. Note: parametersnext_in_list
andflags
are not used. This call should not be used; usepacklist
instead.
voidpack_cat(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist, SV ***next_in_list, U32 flags)
Looks up the type of the lexical variable at positionpo
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.
HV *pad_compname_type(PADOFFSET po)
Return a pointer to the byte-encoded representation of the SV. May cause the SV to be downgraded from UTF-8 as a side-effect.
Usually accessed via theSvPVbyte_nolen
macro.
char*sv_2pvbyte_nolen(SV* sv)
Return a pointer to the UTF-8-encoded representation of the SV. May cause the SV to be upgraded to UTF-8 as a side-effect.
Usually accessed via theSvPVutf8_nolen
macro.
char*sv_2pvutf8_nolen(SV* sv)
Likesv_2pv()
, but doesn't return the length too. You should usually use the macro wrapperSvPV_nolen(sv)
instead.
char*sv_2pv_nolen(SV* sv)
Likesv_catpvn
, but also handles 'set' magic.
voidsv_catpvn_mg(SV *sv, const char *ptr, STRLEN len)
Likesv_catsv
, but also handles 'set' magic.
voidsv_catsv_mg(SV *dsv, SV *ssv)
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 anxpvmg
. See also"sv_force_normal_flags"
.
voidsv_force_normal(SV *sv)
A private implementation of theSvIVx
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
IVsv_iv(SV* sv)
Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test for aNULL
function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" bysv_nosharing()
.
voidsv_nolocking(SV *sv)
Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid test for aNULL
function pointer and because it could potentially warn under some level of strict-ness.
"Superseded" bysv_nosharing()
.
voidsv_nounlocking(SV *sv)
A private implementation of theSvNVx
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
NVsv_nv(SV* sv)
Use theSvPV_nolen
macro instead
char*sv_pv(SV *sv)
UseSvPVbyte_nolen
instead.
char*sv_pvbyte(SV *sv)
A private implementation of theSvPVbyte
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvbyten(SV *sv, STRLEN *lp)
A private implementation of theSvPV
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvn(SV *sv, STRLEN *lp)
Use theSvPVutf8_nolen
macro instead
char*sv_pvutf8(SV *sv)
A private implementation of theSvPVutf8
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvutf8n(SV *sv, STRLEN *lp)
Taint an SV. UseSvTAINTED_on
instead.
voidsv_taint(SV* sv)
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 ofnewSVrv
. This issv_unref_flags
with theflag
being zero. See"SvROK_off"
.
voidsv_unref(SV* sv)
Tells an SV to useptr
to find its string value. Implemented by callingsv_usepvn_flags
withflags
of 0, hence does not handle 'set' magic. See"sv_usepvn_flags"
.
voidsv_usepvn(SV* sv, char* ptr, STRLEN len)
Likesv_usepvn
, but also handles 'set' magic.
voidsv_usepvn_mg(SV *sv, char *ptr, STRLEN len)
A private implementation of theSvUVx
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
UVsv_uv(SV* sv)
The engine implementingunpack()
Perl function. Note: parametersstrbeg
,new_s
andocnt
are not used. This call should not be used, useunpackstring
instead.
I32unpack_str(const char *pat, const char *patend, const char *s, const char *strbeg, const char *strend, char **new_s, I32 ocnt, U32 flags)
DEPRECATED! It is planned to remove this function 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 strings
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.
Ifs
points to one of the detected malformations, and UTF8 warnings are enabled, zero is returned and*retlen
is set (ifretlen
isn'tNULL
) 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 (ifretlen
isn't NULL) so that (s
+*retlen
) is the next possible position ins
that could begin a non-malformed character. See"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
UVutf8_to_uvchr(const U8 *s, STRLEN *retlen)
DEPRECATED! It is planned to remove this function from a future release of Perl. Do not use it for new code; remove it from existing code.
Returns the Unicode code point of the first character in the strings
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 one reason why this function is deprecated. The other is that only in extremely limited circumstances should the Unicode versus native code point be of any interest to you. See"utf8_to_uvuni_buf" for alternatives.
Ifs
points to one of the detected malformations, and UTF8 warnings are enabled, zero is returned and*retlen
is set (ifretlen
doesn't point to 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 (ifretlen
isn't NULL) so that (s
+*retlen
) is the next possible position ins
that could begin a non-malformed character. See"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
UVutf8_to_uvuni(const U8 *s, STRLEN *retlen)
Constructs, checks, and returns an assignment op.left
andright
supply the parameters of the assignment; they are consumed by this function and become part of the constructed op tree.
Ifoptype
isOP_ANDASSIGN
,OP_ORASSIGN
, orOP_DORASSIGN
, then a suitable conditional optree is constructed. Ifoptype
is the opcode of a binary operator, such asOP_BIT_OR
, then an op is constructed that performs the binary operation and assigns the result to the left argument. Either way, ifoptype
is non-zero thenflags
has no effect.
Ifoptype
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 ofop_flags
, except thatOPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits ofop_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)
Constructs, checks, and returns an op of any binary type.type
is the opcode.flags
gives the eight bits ofop_flags
, except thatOPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits ofop_private
, except that the bit with value 1 or 2 is automatically set as required.first
andlast
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)
Constructs, checks, and returns a conditional-expression (cond_expr
) op.flags
gives the eight bits ofop_flags
, except thatOPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits ofop_private
, except that the bit with value 1 is automatically set.first
supplies the expression selecting between the two branches, andtrueop
andfalseop
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)
Constructs and returns an op to access$_
.
OP *newDEFSVOP()
Constructs, checks, and returns an op tree expressing aforeach
loop (iteration through a list of values). This is a heavyweight loop, with structure that allows exiting the loop bylast
and suchlike.
sv
optionally supplies the variable that will be aliased to each item in turn; if null, it defaults to$_
.expr
supplies the list of values to iterate over.block
supplies the main body of the loop, andcont
optionally supplies acontinue
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 ofop_flags
for theleaveloop
op and, shifted up eight bits, the eight bits ofop_private
for theleaveloop
op, except that (in both cases) some bits will be set automatically.
OP *newFOROP(I32 flags, OP *sv, OP *expr, OP *block, OP *cont)
Constructs, checks, and returns an op tree expressing agiven
block.cond
supplies the expression that will be locally assigned to a lexical variable, andblock
supplies the body of thegiven
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)
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 ofop_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)
Constructs, checks, and returns an op of any list type.type
is the opcode.flags
gives the eight bits ofop_flags
, except thatOPf_KIDS
will be set automatically if required.first
andlast
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 callingnewLISTOP(OP_JOIN, ...)
(e.g.) is not appropriate. What you want to do in that case is create an op of typeOP_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)
Constructs, checks, and returns a logical (flow control) op.type
is the opcode.flags
gives the eight bits ofop_flags
, except thatOPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits ofop_private
, except that the bit with value 1 is automatically set.first
supplies the expression controlling the flow, andother
supplies the side (alternate) chain of ops; they are consumed by this function and become part of the constructed op tree.
OP *newLOGOP(I32 type, I32 flags, OP *first, OP *other)
Constructs, checks, and returns a loop-exiting op (such asgoto
orlast
).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)
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 bylast
and suchlike.flags
gives the eight bits ofop_flags
for the top-level op, except that some bits will be set automatically as required.expr
supplies the expression controlling loop iteration, andblock
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)
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 ofop_flags
, except thatOPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits ofop_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 *first)
Constructs, checks, and returns an op of method type with a constant method name.type
is the opcode.flags
gives the eight bits ofop_flags
, and, shifted up eight bits, the eight bits ofop_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)
Constructs, checks, and returns a newstub
op, which represents an empty list expression.
OP *newNULLLIST()
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 ofop_flags
, and, shifted up eight bits, the eight bits ofop_private
.
OP *newOP(I32 type, I32 flags)
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 ofop_flags
. A pad slot is automatically allocated, and is populated withsv
; 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)
Constructs, checks, and returns an op of any pattern matching type.type
is the opcode.flags
gives the eight bits ofop_flags
and, shifted up eight bits, the eight bits ofop_private
.
OP *newPMOP(I32 type, I32 flags)
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 ofop_flags
.pv
supplies the C-level pointer, which must have been allocated usingPerlMemShared_malloc
; the memory will be freed when the op is destroyed.
OP *newPVOP(I32 type, I32 flags, char *pv)
Constructs and returns arange
op, with subordinateflip
andflop
ops.flags
gives the eight bits ofop_flags
for theflip
op and, shifted up eight bits, the eight bits ofop_private
for both theflip
andrange
ops, except that the bit with value 1 is automatically set.left
andright
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)
Constructs, checks, and returns anlslice
(list slice) op.flags
gives the eight bits ofop_flags
, except thatOPf_KIDS
will be set automatically, and, shifted up eight bits, the eight bits ofop_private
, except that the bit with value 1 or 2 is automatically set as required.listval
andsubscript
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 *listval)
Constructs a state op (COP). The state op is normally anextstate
op, but will be adbstate
op if debugging is enabled for currently-compiled code. The state op is populated fromPL_curcop
(orPL_compiling
). Iflabel
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 bylabel
, and will free it.flags
gives the eight bits ofop_flags
for the state op.
Ifo
is null, the state op is returned. Otherwise the state op is combined witho
into alineseq
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)
Constructs, checks, and returns an op of any type that involves an embedded SV.type
is the opcode.flags
gives the eight bits ofop_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)
Constructs, checks, and returns an op of any unary type.type
is the opcode.flags
gives the eight bits ofop_flags
, except thatOPf_KIDS
will be set automatically if required, and, shifted up eight bits, the eight bits ofop_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)
Similar tonewUNOP
, but creates anUNOP_AUX
struct instead, withop_aux
initialised toaux
OP*newUNOP_AUX(I32 type, I32 flags, OP* first, UNOP_AUX_item *aux)
Constructs, checks, and returns an op tree expressing awhen
block.cond
supplies the test expression, andblock
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 adefault
block.
OP *newWHENOP(OP *cond, OP *block)
Constructs, checks, and returns an op tree expressing awhile
loop. This is a heavyweight loop, with structure that allows exiting the loop bylast
and suchlike.
loop
is an optional preconstructedenterloop
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, andcont
optionally supplies acontinue
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 ofop_flags
for theleaveloop
op and, shifted up eight bits, the eight bits ofop_private
for theleaveloop
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)
NOTE: this function is experimental and may change or be removed without notice.
Available only under threaded builds, this function allocates an entry inPL_stashpad
for the stash passed to it.
PADOFFSET alloccopstash(HV *hv)
Handles compile-time scope exit.floor
is the savestack index returned byblock_start
, andseq
is the body of the block. Returns the block, possibly modified.
OP *block_end(I32 floor, OP *seq)
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 withblock_end
.
intblock_start(int full)
Performs the default fixup of the arguments part of anentersub
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)
Performs the fixup of the arguments part of anentersub
op tree based on a subroutine prototype. This makes various modifications to the argument ops, from applying context up to insertingrefgen
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 (aCV*
that has been cast toSV*
) 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 thenamegv
parameter.
OP *ck_entersub_args_proto(OP *entersubop, GV *namegv, SV *protosv)
Performs the fixup of the arguments part of anentersub
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 (aCV*
that has been cast toSV*
), 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 thenamegv
parameter.
OP *ck_entersub_args_proto_or_list(OP *entersubop, GV *namegv, SV *protosv)
Ifcv
is a constant sub eligible for inlining, returns the constant value returned by the sub. Otherwise, returnsNULL
.
Constant subs can be created withnewCONSTSUB
or as described in"Constant Functions" in perlsub.
SV*cv_const_sv(const CV *const cv)
Retrieves the function that will be used to fix up a call tocv
. Specifically, the function is applied to anentersub
op tree for a subroutine call, not marked with&
, where the callee can be identified at compile time ascv
.
The C-level function pointer is returned in*ckfun_p
, and an SV argument for it is returned in*ckobj_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 theentersub
op, which may be replaced by the check function, andnamegv
is a GV supplying the name that should be used by the check function to refer to the callee of theentersub
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.
By default, the function isPerl_ck_entersub_args_proto_or_list, and the SV parameter iscv
itself. This implements standard prototype processing. It can be changed, for a particular subroutine, by"cv_set_call_checker".
voidcv_get_call_checker(CV *cv, Perl_call_checker *ckfun_p, SV **ckobj_p)
The original form of"cv_set_call_checker_flags", which passes it theCALL_CHECKER_REQUIRE_GV
flag for backward-compatibility.
voidcv_set_call_checker(CV *cv, Perl_call_checker ckfun, SV *ckobj)
Sets the function that will be used to fix up a call tocv
. Specifically, the function is applied to anentersub
op tree for a subroutine call, not marked with&
, where the callee can be identified at compile time ascv
.
The C-level function pointer is supplied inckfun
, and an SV argument for it is supplied inckobj
. 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 theentersub
op, which may be replaced by the check function, andnamegv
supplies the name that should be used by the check function to refer to the callee of theentersub
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 includingCALL_CHECKER_REQUIRE_GV
in theflags
.
The current setting for a particular CV can be retrieved by"cv_get_call_checker".
voidcv_set_call_checker_flags( CV *cv, Perl_call_checker ckfun, SV *ckobj, U32 flags)
Given the root of an optree, link the tree in execution order using theop_next
pointers and return the first op executed. If this has already been done, it will not be redone, ando->op_next
will be returned. Ifo->op_next
is not already set,o
should be at least anUNOP
.
OP*LINKLIST(OP *o)
CV*newCONSTSUB(HV* stash, const char* name, SV* sv)
Creates a constant sub equivalent to Perlsub FOO () { 123 }
which is eligible for inlining at compile-time.
Currently, the only useful value forflags
isSVf_UTF8
.
The newly created subroutine takes ownership of a reference to the passed in SV.
PassingNULL
for SV creates a constant sub equivalent tosub BAR () {}
, which won't be called if used as a destructor, but will suppress the overhead of a call toAUTOLOAD
. (This form, however, isn't eligible for inlining at compile time.)
CV*newCONSTSUB_flags(HV* stash, const char* name, STRLEN len, U32 flags, SV* sv)
Used byxsubpp
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.
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, andlast
is the op to append to the list.optype
specifies the intended opcode for the list. Iffirst
is not already a list of the right type, it will be upgraded into one. If eitherfirst
orlast
is null, the other is returned unchanged.
OP *op_append_elem(I32 optype, OP *first, OP *last)
Concatenate the lists of ops contained directly within two list-type ops, returning the combined list.first
andlast
are the list-type ops to concatenate.optype
specifies the intended opcode for the list. If eitherfirst
orlast
is not already a list of the right type, it will be upgraded into one. If eitherfirst
orlast
is null, the other is returned unchanged.
OP *op_append_list(I32 optype, OP *first, OP *last)
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 ofPL_opargs
, which does not always accurately reflect the type used. 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 theOA_
* constants fromop.h.
U32OP_CLASS(OP *o)
Applies a syntactic context to an op tree representing an expression.o
is the op tree, andcontext
must beG_SCALAR
,G_ARRAY
, orG_VOID
to specify the context to apply. The modified op tree is returned.
OP *op_contextualize(OP *o, I32 context)
Convertso
into a list op if it is not one already, and then converts it into the specifiedtype
, 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 vianewLISTOP
,op_prepend_elem
andop_append_elem
. Then finally it is passed toop_convert_list
to make it the right type.
OP *op_convert_list(I32 type, I32 flags, OP *o)
Return a short description of the provided OP.
const char * OP_DESC(OP *o)
Free an op. Only use this when an op is no longer linked to from any optree.
voidop_free(OP *o)
Returns true ifo
has a sibling
boolOpHAS_SIBLING(OP *o)
Markso
as having no further siblings. OnPERL_OP_PARENT
builds, marks o as having the specified parent. See also"OpMORESIB_set"
andOpMAYBESIB_set
. For a higher-level interface, see"op_sibling_splice"
.
voidOpLASTSIB_set(OP *o, OP *parent)
This function is the implementation of the"LINKLIST" macro. It should not be called directly.
OP*op_linklist(OP *o)
NOTE: this function 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, althoughlocal()
is represented byOP_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 typeOP_ADD
and atype
argument ofOP_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)
Conditionally doesOpMORESIB_set
orOpLASTSIB_set
depending on whethersib
is non-null. For a higher-level interface, see"op_sibling_splice"
.
voidOpMAYBESIB_set(OP *o, OP *sib, OP *parent)
Sets the sibling ofo
to the non-zero valuesib
. See also"OpLASTSIB_set"
and"OpMAYBESIB_set"
. For a higher-level interface, see"op_sibling_splice"
.
voidOpMORESIB_set(OP *o, OP *sib)
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)
Neutralizes an op when it is no longer needed, but is still linked to from other ops.
voidop_null(OP *o)
Returns the parent OP ofo
, if it has a parent. ReturnsNULL
otherwise. This function is only available on perls built with-DPERL_OP_PARENT
.
OP*op_parent(OP *o)
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, andlast
is the list-type op.optype
specifies the intended opcode for the list. Iflast
is not already a list of the right type, it will be upgraded into one. If eitherfirst
orlast
is null, the other is returned unchanged.
OP *op_prepend_elem(I32 optype, OP *first, OP *last)
NOTE: this function 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 anenter
/leave
pair, but ascope
op may be used instead if the ops are simple enough to not need the full dynamic scope structure.
OP *op_scope(OP *o)
Returns the sibling ofo
, orNULL
if there is no sibling
OP*OpSIBLING(OP *o)
A general function for editing the structure of an existing chain of op_sibling nodes. By analogy with the perl-levelsplice()
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 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 asNULL
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 isNULL
, 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. IfNULL
, no nodes are inserted.
The head of the chain of deleted ops is returned, orNULL
if no ops were deleted.
For example:
action before after returns------ ----- ----- ------- P Psplice(P, A, 2, X-Y-Z) | | B-C A-B-C-D A-X-Y-Z-D P Psplice(P, NULL, 1, X-Y) | | A A-B-C-D X-Y-B-C-D P Psplice(P, NULL, 3, NULL) | | A-B-C A-B-C-D D P Psplice(P, B, 0, X-Y) | | NULL A-B-C-D A-B-X-Y-C-D
For lower-level direct manipulation ofop_sibparent
andop_moresib
, see"OpMORESIB_set"
,"OpLASTSIB_set"
,"OpMAYBESIB_set"
.
OP*op_sibling_splice(OP *parent, OP *start, int del_count, OP* insert)
Returns true if the given OP is not aNULL
pointer and if it is of the given type.
The negation of this macro,OP_TYPE_ISNT
is also available as well asOP_TYPE_IS_NN
andOP_TYPE_ISNT_NN
which elide the NULL pointer check.
boolOP_TYPE_IS(OP *o, Optype type)
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 asOP_TYPE_IS_OR_WAS_NN
andOP_TYPE_ISNT_AND_WASNT_NN
which elide theNULL
pointer check.
boolOP_TYPE_IS_OR_WAS(OP *o, Optype type)
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 anrv2cv
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 therv2cv
is to operate on is provided by a suitablegv
orconst
op. Agv
op is suitable if the GV's CV slot is populated. Aconst
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 therv2cv
op has theOPpENTERSUB_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.
Ifflags
has the bitRV2CVOPCV_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 thegv
op has theOPpEARLY_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".
Ifflags
has the bitRV2CVOPCV_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 theCvGV
of the subroutine, but for an anonymous (CvANON
) subroutine that is referenced through a GV it will be the referencing GV. The resultingGV*
is cast toCV*
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)
The engine implementingpack()
Perl function.
voidpacklist(SV *cat, const char *pat, const char *patend, SV **beglist, SV **endlist)
The engine implementing theunpack()
Perl function.
Using the templatepat..patend
, this function unpacks the strings..strend
into a number of mortal SVs, which it pushes onto the perl argument (@_
) stack (so you will need to issue aPUTBACK
before andSPAGAIN
after the call to this function). It returns the number of pushed elements.
Thestrend
andpatend
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 aPUSHMARK
before calling it, unlike"call_pv" for example).
I32unpackstring(const char *pat, const char *patend, const char *s, const char *strend, U32 flags)
NOTE: this function 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 aCvPADLIST
.dXSTARG
fetches values fromPL_curpad
, but that is really the callers pad (a slot of which is allocated by every entersub). Do not get or setCvPADLIST
if a CV is an XSUB (as determined byCvISXSUB()
),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)
andPadnamePV(name) && !PadnameLEN(name)
, respectively.
Onlymy
/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 waymy
/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 inPL_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. TheCOP_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 ($xvalid-seq# PERL_PADSEQ_INTRO variable in scope: { my ($x)valid-seq# valid-seq# compilation of scope complete: { my ($x) }
For typed lexicalsPadnameTYPE
points at the type stash. Forour
lexicals,PadnameOURSTASH
points at the stash of the associated global (so that duplicateour
declarations in the same package can be detected).PadnameGEN
is sometimes used to store the generation number during compilation.
IfPadnameOUTER
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 flagSVs_PADSTALE
is cleared on lexicals each time themy()
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)
Exactly like"pad_add_name_pvn", but takes aNUL
-terminated literal string instead of a string/length pair.
PADOFFSET pad_add_name_pvs(const char *name, U32 flags, HV *typestash, HV *ourstash)
NOTE: this function is experimental and may change or be removed without notice.
The C array of pad entries.
SV **PadARRAY(PAD pad)
Exactly like"pad_findmy_pvn", but takes aNUL
-terminated literal string instead of a string/length pair.
PADOFFSET pad_findmy_pvs(const char *name, U32 flags)
NOTE: this function 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)
NOTE: this function 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 beNULL
in that case.
SSize_tPadlistMAX(PADLIST padlist)
NOTE: this function is experimental and may change or be removed without notice.
The names associated with pad entries.
PADNAMELIST * PadlistNAMES(PADLIST padlist)
NOTE: this function is experimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadlistNAMESARRAY(PADLIST padlist)
NOTE: this function is experimental and may change or be removed without notice.
The index of the last pad name.
SSize_tPadlistNAMESMAX(PADLIST padlist)
NOTE: this function is experimental and may change or be removed without notice.
The reference count of the padlist. Currently this is always 1.
U32PadlistREFCNT(PADLIST padlist)
NOTE: this function is experimental and may change or be removed without notice.
The index of the last pad entry.
SSize_tPadMAX(PAD pad)
NOTE: this function is experimental and may change or be removed without notice.
The length of the name.
STRLENPadnameLEN(PADNAME pn)
NOTE: this function is experimental and may change or be removed without notice.
The C array of pad names.
PADNAME ** PadnamelistARRAY(PADNAMELIST pnl)
NOTE: this function is experimental and may change or be removed without notice.
The index of the last pad name.
SSize_tPadnamelistMAX(PADNAMELIST pnl)
NOTE: this function is experimental and may change or be removed without notice.
The reference count of the pad name list.
SSize_tPadnamelistREFCNT(PADNAMELIST pnl)
NOTE: this function is experimental and may change or be removed without notice.
Lowers the reference count of the pad name list.
voidPadnamelistREFCNT_dec(PADNAMELIST pnl)
NOTE: this function is experimental and may change or be removed without notice.
The name stored in the pad name struct. This returnsNULL
for a target slot.
char *PadnamePV(PADNAME pn)
NOTE: this function is experimental and may change or be removed without notice.
The reference count of the pad name.
SSize_tPadnameREFCNT(PADNAME pn)
NOTE: this function is experimental and may change or be removed without notice.
Lowers the reference count of the pad name.
voidPadnameREFCNT_dec(PADNAME pn)
NOTE: this function is experimental and may change or be removed without notice.
Returns the pad name as a mortal SV.
SV *PadnameSV(PADNAME pn)
NOTE: this function is experimental and may change or be removed without notice.
Whether PadnamePV is in UTF-8. Currently, this is always true.
boolPadnameUTF8(PADNAME pn)
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_CLONEthis pad is for a cloned CV padnew_SAVEsave old globals on the save stack padnew_SAVESUBalso save extra stuff for start of subPADLIST * pad_new(int flags)
NOTE: this function 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.
NOTE: this function 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.
NOTE: this function is experimental and may change or be removed without notice.
Points directly to the body of the"PL_comppad" array. (I.e., this isPAD_ARRAY(PL_comppad)
.)
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.
HV*PL_modglobal
A convenience variable which is typically used withSvPV
when one doesn't care about the length of the string. It is usually more efficient to either declare a local variable and use that instead or to use theSvPV_nolen
macro.
STRLENPL_na
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.
Perl_ophook_tPL_opfreehook
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.
peep_tPL_peepp
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 theirop_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.
peep_tPL_rpeepp
This is thefalse
SV. See"PL_sv_yes"
. Always refer to this as&PL_sv_no
.
SVPL_sv_no
This is theundef
SV. Always refer to this as&PL_sv_undef
.
SVPL_sv_undef
This is thetrue
SV. See"PL_sv_no"
. Always refer to this as&PL_sv_yes
.
SVPL_sv_yes
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)
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.
boolSvRXOK(SV* sv)
Declare a stack marker variable,mark
, for the XSUB. See"MARK"
and"dORIGMARK"
.
dMARK;
Saves the original stack mark for the XSUB. See"ORIGMARK"
.
dORIGMARK;
Declares a local copy of perl's stack pointer for the XSUB, available via theSP
macro. See"SP"
.
dSP;
Used to extend the argument stack for an XSUB's return values. Once used, guarantees that there is room for at leastnitems
to be pushed onto the stack.
voidEXTEND(SP, SSize_t nitems)
Stack marker variable for the XSUB. See"dMARK"
.
Push an integer onto the stack. The stack must have room for this element. Does not useTARG
. See also"PUSHi"
,"mXPUSHi"
and"XPUSHi"
.
voidmPUSHi(IV iv)
Push a double onto the stack. The stack must have room for this element. Does not useTARG
. See also"PUSHn"
,"mXPUSHn"
and"XPUSHn"
.
voidmPUSHn(NV nv)
Push a string onto the stack. The stack must have room for this element. Thelen
indicates the length of the string. Does not useTARG
. See also"PUSHp"
,"mXPUSHp"
and"XPUSHp"
.
voidmPUSHp(char* str, STRLEN len)
Push an SV onto the stack and mortalizes the SV. The stack must have room for this element. Does not useTARG
. See also"PUSHs"
and"mXPUSHs"
.
voidmPUSHs(SV* sv)
Push an unsigned integer onto the stack. The stack must have room for this element. Does not useTARG
. See also"PUSHu"
,"mXPUSHu"
and"XPUSHu"
.
voidmPUSHu(UV uv)
Push an integer onto the stack, extending the stack if necessary. Does not useTARG
. See also"XPUSHi"
,"mPUSHi"
and"PUSHi"
.
voidmXPUSHi(IV iv)
Push a double onto the stack, extending the stack if necessary. Does not useTARG
. See also"XPUSHn"
,"mPUSHn"
and"PUSHn"
.
voidmXPUSHn(NV nv)
Push a string onto the stack, extending the stack if necessary. Thelen
indicates the length of the string. Does not useTARG
. See also"XPUSHp"
,mPUSHp
andPUSHp
.
voidmXPUSHp(char* str, STRLEN len)
Push an SV onto the stack, extending the stack if necessary and mortalizes the SV. Does not useTARG
. See also"XPUSHs"
and"mPUSHs"
.
voidmXPUSHs(SV* sv)
Push an unsigned integer onto the stack, extending the stack if necessary. Does not useTARG
. See also"XPUSHu"
,"mPUSHu"
and"PUSHu"
.
voidmXPUSHu(UV uv)
The original stack mark for the XSUB. See"dORIGMARK"
.
Pops an integer off the stack.
IVPOPi
Pops a long off the stack.
longPOPl
Pops a double off the stack.
NVPOPn
Pops a string off the stack.
char*POPp
Pops a string off the stack which must consist of bytes i.e. characters < 256.
char*POPpbytex
Pops a string off the stack. Identical to POPp. There are two names for historical reasons.
char*POPpx
Pops an SV off the stack.
SV*POPs
Pops an unsigned integer off the stack.
UVPOPu
Pops an unsigned long off the stack.
longPOPul
Push an integer onto the stack. The stack must have room for this element. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mPUSHi"
instead. See also"XPUSHi"
and"mXPUSHi"
.
voidPUSHi(IV iv)
Opening bracket for arguments on a callback. See"PUTBACK"
andperlcall.
voidPUSHMARK(SP)
Push a new mortal SV onto the stack. The stack must have room for this element. Does not useTARG
. See also"PUSHs"
,"XPUSHmortal"
and"XPUSHs"
.
voidPUSHmortal()
Push a double onto the stack. The stack must have room for this element. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mPUSHn"
instead. See also"XPUSHn"
and"mXPUSHn"
.
voidPUSHn(NV nv)
Push a string onto the stack. The stack must have room for this element. Thelen
indicates the length of the string. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mPUSHp"
instead. See also"XPUSHp"
and"mXPUSHp"
.
voidPUSHp(char* str, STRLEN len)
Push an SV onto the stack. The stack must have room for this element. Does not handle 'set' magic. Does not useTARG
. See also"PUSHmortal"
,"XPUSHs"
, and"XPUSHmortal"
.
voidPUSHs(SV* sv)
Push an unsigned integer onto the stack. The stack must have room for this element. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mPUSHu"
instead. See also"XPUSHu"
and"mXPUSHu"
.
voidPUSHu(UV uv)
Closing bracket for XSUB arguments. This is usually handled byxsubpp
. See"PUSHMARK"
andperlcall for other uses.
PUTBACK;
Stack pointer. This is usually handled byxsubpp
. See"dSP"
andSPAGAIN
.
Refetch the stack pointer. Used after a callback. Seeperlcall.
SPAGAIN;
Push an integer onto the stack, extending the stack if necessary. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mXPUSHi"
instead. See also"PUSHi"
and"mPUSHi"
.
voidXPUSHi(IV iv)
Push a new mortal SV onto the stack, extending the stack if necessary. Does not useTARG
. See also"XPUSHs"
,"PUSHmortal"
and"PUSHs"
.
voidXPUSHmortal()
Push a double onto the stack, extending the stack if necessary. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mXPUSHn"
instead. See also"PUSHn"
and"mPUSHn"
.
voidXPUSHn(NV nv)
Push a string onto the stack, extending the stack if necessary. Thelen
indicates the length of the string. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mXPUSHp"
instead. See also"PUSHp"
and"mPUSHp"
.
voidXPUSHp(char* str, STRLEN len)
Push an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. Does not useTARG
. See also"XPUSHmortal"
,PUSHs
andPUSHmortal
.
voidXPUSHs(SV* sv)
Push an unsigned integer onto the stack, extending the stack if necessary. Handles 'set' magic. UsesTARG
, sodTARGET
ordXSTARG
should be called to declare it. Do not call multipleTARG
-oriented macros to return lists from XSUB's - see"mXPUSHu"
instead. See also"PUSHu"
and"mPUSHu"
.
voidXPUSHu(UV uv)
Return from XSUB, indicating number of items on the stack. This is usually handled byxsubpp
.
voidXSRETURN(int nitems)
Return an empty list from an XSUB immediately.
XSRETURN_EMPTY;
Return an integer from an XSUB immediately. UsesXST_mIV
.
voidXSRETURN_IV(IV iv)
Return&PL_sv_no
from an XSUB immediately. UsesXST_mNO
.
XSRETURN_NO;
Return a double from an XSUB immediately. UsesXST_mNV
.
voidXSRETURN_NV(NV nv)
Return a copy of a string from an XSUB immediately. UsesXST_mPV
.
voidXSRETURN_PV(char* str)
Return&PL_sv_undef
from an XSUB immediately. UsesXST_mUNDEF
.
XSRETURN_UNDEF;
Return an integer from an XSUB immediately. UsesXST_mUV
.
voidXSRETURN_UV(IV uv)
Return&PL_sv_yes
from an XSUB immediately. UsesXST_mYES
.
XSRETURN_YES;
Place an integer into the specified positionpos
on the stack. The value is stored in a new mortal SV.
voidXST_mIV(int pos, IV iv)
Place&PL_sv_no
into the specified positionpos
on the stack.
voidXST_mNO(int pos)
Place a double into the specified positionpos
on the stack. The value is stored in a new mortal SV.
voidXST_mNV(int pos, NV nv)
Place a copy of a string into the specified positionpos
on the stack. The value is stored in a new mortal SV.
voidXST_mPV(int pos, char* str)
Place&PL_sv_undef
into the specified positionpos
on the stack.
voidXST_mUNDEF(int pos)
Place&PL_sv_yes
into the specified positionpos
on the stack.
voidXST_mYES(int pos)
Test if the content of an SV looks like a number (or is a number).Inf
andInfinity
are treated as numbers (so will not issue a non-numeric warning), even if youratof()
doesn't grok them. Get-magic is ignored.
I32looks_like_number(SV *const sv)
Creates an RV wrapper for an SV. The reference count for the original SV isnot incremented.
SV*newRV_noinc(SV *const tmpRef)
Creates a new SV. A non-zerolen
parameter indicates the number of bytes of preallocated string space the SV should have. An extra byte for a trailingNUL
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 olderNEWSV()
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)
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 ifhek
is NULL.
SV*newSVhek(const HEK *const hek)
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)
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)
Creates a new SV and copies a string (which may containNUL
(\0
) characters) into it. The reference count for the SV is set to 1. Iflen
is zero, Perl will compute the length usingstrlen()
, (which means if you use this option, thats
can't have embeddedNUL
characters and has to have a terminatingNUL
byte).
For efficiency, consider usingnewSVpvn
instead.
SV*newSVpv(const char *const s, const STRLEN len)
Creates a new SV and initializes it with the string formatted likesv_catpvf
.
SV*newSVpvf(const char *const pat, ...)
Creates a new SV and copies a string into it, which may containNUL
characters (\0
) and other binary data. The reference count for the SV is set to 1. Note that iflen
is zero, Perl will create a zero length (Perl) string. You are responsible for ensuring that the source buffer is at leastlen
bytes long. If thebuffer
argument is NULL the new SV will be undefined.
SV*newSVpvn(const char *const s, const STRLEN len)
Creates a new SV and copies a string (which may containNUL
(\0
) characters) into it. The reference count for the SV is set to 1. Note that iflen
is zero, Perl will create a zero length string. You are responsible for ensuring that the source string is at leastlen
bytes long. If thes
argument is NULL the new SV will be undefined. Currently the only flag bits accepted areSVf_UTF8
andSVs_TEMP
. IfSVs_TEMP
is set, thensv_2mortal()
is called on the result before returning. IfSVf_UTF8
is set,s
is considered to be in UTF-8 and theSVf_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)
Creates a new SV with itsSvPVX_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 theSvIsCOW
flag (orREADONLY
andFAKE
in 5.16 and earlier). If thehash
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 theSvSHARED_HASH()
macro. The idea here is that as the string table is used for shared hash keys these strings will haveSvPVX_const == HeKEY
and hash lookup will avoid string compare.
SV*newSVpvn_share(const char* s, I32 len, U32 hash)
LikenewSVpvn
, but takes aNUL
-terminated literal string instead of a string/length pair.
SV*newSVpvs(const char* s)
LikenewSVpvn_flags
, but takes aNUL
-terminated literal string instead of a string/length pair.
SV*newSVpvs_flags(const char* s, U32 flags)
LikenewSVpvn_share
, but takes aNUL
-terminated string instead of a string/length pair.
SV*newSVpv_share(const char* s, U32 hash)
LikenewSVpvn_share
, but takes aNUL
-terminated literal string instead of a string/length pair and omits the hash parameter.
SV*newSVpvs_share(const char* s)
Creates a new SV for the existing RV,rv
, to point to. Ifrv
is not an RV then it will be upgraded to one. Ifclassname
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 byrv
.
SV*newSVrv(SV *const rv, const char *const classname)
Creates a new SV which is an exact duplicate of the original SV. (Usessv_setsv
.)
SV*newSVsv(SV *const old)
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)
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)
This macro is only used bysv_true()
or its macro equivalent, and only if the latter's argument is neitherSvPOK
,SvIOK
norSvNOK
. It callssv_2bool_flags
with theSV_GMAGIC
flag.
boolsv_2bool(SV *const sv)
This function is only used bysv_true()
and friends, and only if the latter's argument is neitherSvPOK
,SvIOK
norSvNOK
. If the flags containSV_GMAGIC
, then it does anmg_get()
first.
boolsv_2bool_flags(SV *sv, I32 flags)
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 inlref
are passed togv_fetchsv
.
CV*sv_2cv(SV* sv, HV **const st, GV **const gvp, const I32 lref)
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 thesv
passed in, but will be called onSvRV(sv)
ifsv
is an RV.
IO*sv_2io(SV *const sv)
Return the integer value of an SV, doing any necessary string conversion. Ifflags
has theSV_GMAGIC
bit set, does anmg_get()
first. Normally used via theSvIV(sv)
andSvIVx(sv)
macros.
IVsv_2iv_flags(SV *const sv, const I32 flags)
Marks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call toFREETMPS
, 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)
Return the num value of an SV, doing any necessary string or integer conversion. Ifflags
has theSV_GMAGIC
bit set, does anmg_get()
first. Normally used via theSvNV(sv)
andSvNVx(sv)
macros.
NVsv_2nv_flags(SV *const sv, const I32 flags)
Return a pointer to the byte-encoded representation of the SV, and set*lp
to its length. May cause the SV to be downgraded from UTF-8 as a side-effect.
Usually accessed via theSvPVbyte
macro.
char*sv_2pvbyte(SV *sv, STRLEN *const lp)
Return a pointer to the UTF-8-encoded representation of the SV, and set*lp
to its length. May cause the SV to be upgraded to UTF-8 as a side-effect.
Usually accessed via theSvPVutf8
macro.
char*sv_2pvutf8(SV *sv, STRLEN *const lp)
Returns a pointer to the string value of an SV, and sets*lp
to its length. If flags has theSV_GMAGIC
bit set, does anmg_get()
first. Coercessv
to a string if necessary. Normally invoked via theSvPV_flags
macro.sv_2pv()
andsv_2pv_nomg
usually end up here too.
char*sv_2pv_flags(SV *const sv, STRLEN *const lp, const I32 flags)
Return the unsigned integer value of an SV, doing any necessary string conversion. Ifflags
has theSV_GMAGIC
bit set, does anmg_get()
first. Normally used via theSvUV(sv)
andSvUVx(sv)
macros.
UVsv_2uv_flags(SV *const sv, const I32 flags)
Remove any string offset. You should normally use theSvOOK_off
macro wrapper instead.
voidsv_backoff(SV *const sv)
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)
Concatenates theNUL
-terminated string 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. Handles 'get' magic, but not 'set' magic. See"sv_catpv_mg"
.
voidsv_catpv(SV *const sv, const char* ptr)
Processes its arguments likesv_catpvfn
, and appends the formatted output to an SV. As withsv_catpvfn
called with a non-null C-style variable argument list, argument reordering is not supported. 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. Handles 'get' magic, but not 'set' magic. See"sv_catpvf_mg"
. 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.
voidsv_catpvf(SV *const sv, const char *const pat, ...)
Likesv_catpvf
, but also handles 'set' magic.
voidsv_catpvf_mg(SV *const sv, const char *const pat, ...)
Concatenates the string onto the end of the string which is in the SV.len
indicates number of bytes to copy. If the SV has the UTF-8 status set, then the bytes appended should be valid UTF-8. Handles 'get' magic, but not 'set' magic. See"sv_catpvn_mg"
.
voidsv_catpvn(SV *dsv, const char *sstr, STRLEN len)
Concatenates the string onto the end of the string which is in the SV. Thelen
indicates number of bytes to copy.
By default, 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. One can force the appended string to be interpreted as UTF-8 by supplying theSV_CATUTF8
flag, and as bytes by supplying theSV_CATBYTES
flag; the SV or the string appended will be upgraded to UTF-8 if necessary.
Ifflags
has theSV_SMAGIC
bit set, willmg_set
ondsv
afterwards if appropriate.sv_catpvn
andsv_catpvn_nomg
are implemented in terms of this function.
voidsv_catpvn_flags(SV *const dstr, const char *sstr, const STRLEN len, const I32 flags)
Likesv_catpvn
, but takes aNUL
-terminated literal string instead of a string/length pair.
voidsv_catpvs(SV* sv, const char* s)
Likesv_catpvn_flags
, but takes aNUL
-terminated literal string instead of a string/length pair.
voidsv_catpvs_flags(SV* sv, const char* s, I32 flags)
Likesv_catpvn_mg
, but takes aNUL
-terminated literal string instead of a string/length pair.
voidsv_catpvs_mg(SV* sv, const char* s)
Likesv_catpvn_nomg
, but takes aNUL
-terminated literal string instead of a string/length pair.
voidsv_catpvs_nomg(SV* sv, const char* s)
Concatenates theNUL
-terminated string 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. Ifflags
has theSV_SMAGIC
bit set, willmg_set
on the modified SV if appropriate.
voidsv_catpv_flags(SV *dstr, const char *sstr, const I32 flags)
Likesv_catpv
, but also handles 'set' magic.
voidsv_catpv_mg(SV *const sv, const char *const ptr)
Concatenates the string from SVssv
onto the end of the string in SVdsv
. Ifssv
is null, does nothing; otherwise modifies onlydsv
. Handles 'get' magic on both SVs, but no 'set' magic. See"sv_catsv_mg"
and"sv_catsv_nomg"
.
voidsv_catsv(SV *dstr, SV *sstr)
Concatenates the string from SVssv
onto the end of the string in SVdsv
. Ifssv
is null, does nothing; otherwise modifies onlydsv
. Ifflags
has theSV_GMAGIC
bit set, will callmg_get
on both SVs if appropriate. Ifflags
has theSV_SMAGIC
bit set,mg_set
will be called on the modified SV afterward, if appropriate.sv_catsv
,sv_catsv_nomg
, andsv_catsv_mg
are implemented in terms of this function.
voidsv_catsv_flags(SV *const dsv, SV *const ssv, const I32 flags)
Efficient removal of characters from the beginning of the string buffer.SvPOK(sv)
, or at leastSvPOKp(sv)
, must be true andptr
must be a pointer to somewhere inside the string buffer.ptr
becomes the first character of the adjusted string. Uses theOOK
hack. On return, onlySvPOK(sv)
andSvPOKp(sv)
among theOK
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'schop
operator is strictly coincidental. This function works from the left;chop
works from the right.
voidsv_chop(SV *const sv, const char *const ptr)
Clear an SV: call any destructors, free up any memory used by the body, and free the body itself. The SV's head isnot 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 whenREFCNT
is zero. Most of the time you'll want to callsv_free()
(or its macro wrapperSvREFCNT_dec
) instead.
voidsv_clear(SV *const orig_sv)
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string insv1
is less than, equal to, or greater than the string insv2
. Is UTF-8 and'use bytes'
aware, handles get magic, and will coerce its args to strings if necessary. See also"sv_cmp_locale"
.
I32sv_cmp(SV *const sv1, SV *const sv2)
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string insv1
is less than, equal to, or greater than the string insv2
. Is UTF-8 and'use bytes'
aware and will coerce its args to strings if necessary. If the flags has theSV_GMAGIC
bit set, it handles get magic. See also"sv_cmp_locale_flags"
.
I32sv_cmp_flags(SV *const sv1, SV *const sv2, const U32 flags)
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and'use bytes'
aware, handles get magic, and will coerce its args to strings if necessary. See also"sv_cmp"
.
I32sv_cmp_locale(SV *const sv1, SV *const sv2)
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and'use bytes'
aware and will coerce its args to strings if necessary. If the flags containSV_GMAGIC
, it handles get magic. See also"sv_cmp_flags"
.
I32sv_cmp_locale_flags(SV *const sv1, SV *const sv2, const U32 flags)
This callssv_collxfrm_flags
with the SV_GMAGIC flag. See"sv_collxfrm_flags"
.
char*sv_collxfrm(SV *const sv, STRLEN *const nxp)
Add Collate Transform magic to an SV if it doesn't already have it. If the flags containSV_GMAGIC
, it handles get-magic.
Any scalar variable may carryPERL_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)
Implementation ofsv_copypv
andsv_copypv_nomg
. Calls get magic iff flags has theSV_GMAGIC
bit set.
voidsv_copypv_flags(SV *const dsv, SV *const ssv, const I32 flags)
Likesv_copypv
, but doesn't invoke get magic first.
voidsv_copypv_nomg(SV *const dsv, SV *const ssv)
Auto-decrement of the value in the SV, doing string to numeric conversion if necessary. Handles 'get' magic and operator overloading.
voidsv_dec(SV *const sv)
Auto-decrement of the value in the SV, doing string to numeric conversion if necessary. Handles operator overloading. Skips handling 'get' magic.
voidsv_dec_nomg(SV *const sv)
Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF-8 and'use bytes'
aware, handles get magic, and will coerce its args to strings if necessary.
I32sv_eq(SV* sv1, SV* sv2)
Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF-8 and'use bytes'
aware and coerces its args to strings if necessary. If the flags has theSV_GMAGIC
bit set, it handles get-magic, too.
I32sv_eq_flags(SV* sv1, SV* sv2, const U32 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 anxpvmg
; 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. IfSV_COW_DROP_PV
is set then a copy-on-write scalar drops its PV buffer (if any) and becomesSvPOK_off
rather than making a copy. (Used where this scalar is about to be set to some other value.) In addition, theflags
parameter gets passed tosv_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.
voidsv_force_normal_flags(SV *const sv, const U32 flags)
Decrement an SV's reference count, and if it drops to zero, callsv_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 macroSvREFCNT_dec
.
voidsv_free(SV *const sv)
Get a line from the filehandle and store it into the SV, optionally appending to the currently-stored string. Ifappend
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)
NOTE: this function is experimental and may change or be removed without notice.
Ifsv
is the target of a weak reference then it returns the back references structure associated with the sv; otherwise returnNULL
.
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 alsoPerl_sv_add_backref()
,Perl_sv_del_backref()
,Perl_sv_kill_backrefs()
SV*sv_get_backrefs(SV *const sv)
Expands the character buffer in the SV. If necessary, usessv_unref
and upgrades the SV toSVt_PV
. Returns a pointer to the character buffer. Use theSvGROW
wrapper instead.
char*sv_grow(SV *const sv, STRLEN newlen)
Auto-increment of the value in the SV, doing string to numeric conversion if necessary. Handles 'get' magic and operator overloading.
voidsv_inc(SV *const sv)
Auto-increment of the value in the SV, doing string to numeric conversion if necessary. Handles operator overloading. Skips handling 'get' magic.
voidsv_inc_nomg(SV *const sv)
Inserts a string at the specified offset/length within the SV. Similar to the Perlsubstr()
function. Handles get magic.
voidsv_insert(SV *const bigstr, const STRLEN offset, const STRLEN len, const char *const little, const STRLEN littlelen)
Same assv_insert
, but the extraflags
are passed to theSvPV_force_flags
that applies tobigstr
.
voidsv_insert_flags(SV *const bigstr, const STRLEN offset, const STRLEN len, const char *const little, const STRLEN littlelen, const U32 flags)
Returns a boolean indicating whether the SV is blessed into the specified class. This does not check for subtypes; usesv_derived_from
to verify an inheritance relationship.
intsv_isa(SV* sv, const char *const name)
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.
intsv_isobject(SV* sv)
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 thexpv_cur
slot.
STRLENsv_len(SV *const sv)
Returns the number of characters in the string in an SV, counting wide UTF-8 bytes as a single character. Handles magic and type coercion.
STRLENsv_len_utf8(SV *const sv)
Adds magic to an SV. First upgradessv
to typeSVt_PVMG
if necessary, then adds a new magic item of typehow
to the head of the magic list.
See"sv_magicext"
(whichsv_magic
now calls) for a description of the handling of thename
andnamlen
arguments.
You need to usesv_magicext
to add magic toSvREADONLY
SVs and also to add more than one instance of the samehow
.
voidsv_magic(SV *const sv, SV *const obj, const int how, const char *const name, const I32 namlen)
Adds magic to an SV, upgrading it if necessary. Applies the suppliedvtable
and returns a pointer to the magic added.
Note thatsv_magicext
will allow things thatsv_magic
will not. In particular, you can add magic toSvREADONLY
SVs, and add more than one instance of the samehow
.
Ifnamlen
is greater than zero then asavepvn
copy ofname
is stored, ifnamlen
is zero thenname
is stored as-is and - as another special case - if(name && namlen == HEf_SVKEY)
thenname
is assumed to contain an SV* and is stored as-is with itsREFCNT
incremented.
(This is now used as a subroutine bysv_magic
.)
MAGIC *sv_magicext(SV *const sv, SV *const obj, const int how, const MGVTBL *const vtbl, const char *const name, const I32 namlen)
Creates a new SV which is a copy of the original SV (usingsv_setsv
). The new SV is marked as mortal. It will be destroyed "soon", either by an explicit call toFREETMPS
, or by an implicit call at places such as statement boundaries. See also"sv_newmortal"
and"sv_2mortal"
.
SV*sv_mortalcopy(SV *const oldsv)
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 toFREETMPS
, or by an implicit call at places such as statement boundaries. See also"sv_mortalcopy"
and"sv_2mortal"
.
SV*sv_newmortal()
Increment an SV's reference count. Use theSvREFCNT_inc()
wrapper instead.
SV*sv_newref(SV *const sv)
Converts the value pointed to byoffsetp
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.
Usesv_pos_b2u_flags
in preference, which correctly handles strings longer than 2Gb.
voidsv_pos_b2u(SV *const sv, I32 *const offsetp)
Convertsoffset
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 toSvPV_flags
, and usually should beSV_GMAGIC|SV_CONST_RETURN
to handle magic.
STRLENsv_pos_b2u_flags(SV *const sv, STRLEN const offset, U32 flags)
Converts the value pointed to byoffsetp
from a count of UTF-8 chars from the start of the string, to a count of the equivalent number of bytes; iflenp
is non-zero, it does the same tolenp
, but this time starting from the offset, rather than from the start of the string. Handles magic and type coercion.
Usesv_pos_u2b_flags
in preference, which correctly handles strings longer than 2Gb.
voidsv_pos_u2b(SV *const sv, I32 *const offsetp, I32 *const lenp)
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; iflenp
is non-zero, it does the same tolenp
, but this time starting fromoffset
, rather than from the start of the string. Handles type coercion.flags
is passed toSvPV_flags
, and usually should beSV_GMAGIC|SV_CONST_RETURN
to handle magic.
STRLENsv_pos_u2b_flags(SV *const sv, STRLEN uoffset, STRLEN *const lenp, U32 flags)
The backend for theSvPVbytex_force
macro. Always use the macro instead.
char*sv_pvbyten_force(SV *const sv, STRLEN *const lp)
Get a sensible string out of the SV somehow. A private implementation of theSvPV_force
macro for compilers which can't cope with complex macro expressions. Always use the macro instead.
char*sv_pvn_force(SV* sv, STRLEN* lp)
Get a sensible string out of the SV somehow. Ifflags
has theSV_GMAGIC
bit set, willmg_get
onsv
if appropriate, else not.sv_pvn_force
andsv_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 I32 flags)
The backend for theSvPVutf8x_force
macro. Always use the macro instead.
char*sv_pvutf8n_force(SV *const sv, STRLEN *const lp)
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)
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)
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 usesv_setsv
or one of its many macro front-ends.
voidsv_replace(SV *const sv, SV *const nsv)
Underlying implementation for thereset
Perl function. Note that the perl-level function is vaguely deprecated.
voidsv_reset(const char* s, HV *const stash)
Weaken a reference: set theSvWEAKREF
flag on this RV; give the referred-to SVPERL_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.
SV*sv_rvweaken(SV *const sv)
Copies an integer into the given SV, upgrading first if necessary. Does not handle 'set' magic. See also"sv_setiv_mg"
.
voidsv_setiv(SV *const sv, const IV num)
Likesv_setiv
, but also handles 'set' magic.
voidsv_setiv_mg(SV *const sv, const IV i)
Copies a double into the given SV, upgrading first if necessary. Does not handle 'set' magic. See also"sv_setnv_mg"
.
voidsv_setnv(SV *const sv, const NV num)
Likesv_setnv
, but also handles 'set' magic.
voidsv_setnv_mg(SV *const sv, const NV num)
Copies a string into an SV. The string must be terminated with aNUL
character. Does not handle 'set' magic. See"sv_setpv_mg"
.
voidsv_setpv(SV *const sv, const char *const ptr)
Works likesv_catpvf
but copies the text into the SV instead of appending it. Does not handle 'set' magic. See"sv_setpvf_mg"
.
voidsv_setpvf(SV *const sv, const char *const pat, ...)
Likesv_setpvf
, but also handles 'set' magic.
voidsv_setpvf_mg(SV *const sv, const char *const pat, ...)
Copies an integer into the given SV, also updating its string value. Does not handle 'set' magic. See"sv_setpviv_mg"
.
voidsv_setpviv(SV *const sv, const IV num)
Likesv_setpviv
, but also handles 'set' magic.
voidsv_setpviv_mg(SV *const sv, const IV iv)
Copies a string (possibly containing embeddedNUL
characters) into an SV. Thelen
parameter indicates the number of bytes to be copied. If theptr
argument is NULL the SV will become undefined. Does not handle 'set' magic. See"sv_setpvn_mg"
.
voidsv_setpvn(SV *const sv, const char *const ptr, const STRLEN len)
Likesv_setpvn
, but also handles 'set' magic.
voidsv_setpvn_mg(SV *const sv, const char *const ptr, const STRLEN len)
Likesv_setpvn
, but takes aNUL
-terminated literal string instead of a string/length pair.
voidsv_setpvs(SV* sv, const char* s)
Likesv_setpvn_mg
, but takes aNUL
-terminated literal string instead of a string/length pair.
voidsv_setpvs_mg(SV* sv, const char* s)
Likesv_setpv
, but also handles 'set' magic.
voidsv_setpv_mg(SV *const sv, const char *const ptr)
Copies an integer into a new SV, optionally blessing the SV. Therv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname
argument indicates the package for the blessing. Setclassname
toNULL
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)
Copies a double into a new SV, optionally blessing the SV. Therv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname
argument indicates the package for the blessing. Setclassname
toNULL
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)
Copies a pointer into a new SV, optionally blessing the SV. Therv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. If thepv
argument isNULL
, thenPL_sv_undef
will be placed into the SV. Theclassname
argument indicates the package for the blessing. Setclassname
toNULL
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 thatsv_setref_pvn
copies the string while this copies the pointer.
SV*sv_setref_pv(SV *const rv, const char *const classname, void *const pv)
Copies a string into a new SV, optionally blessing the SV. The length of the string must be specified withn
. Therv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname
argument indicates the package for the blessing. Setclassname
toNULL
to avoid the blessing. The new SV will have a reference count of 1, and the RV will be returned.
Note thatsv_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)
Likesv_setref_pvn
, but takes aNUL
-terminated literal string instead of a string/length pair.
SV *sv_setref_pvs(const char* s)
Copies an unsigned integer into a new SV, optionally blessing the SV. Therv
argument will be upgraded to an RV. That RV will be modified to point to the new SV. Theclassname
argument indicates the package for the blessing. Setclassname
toNULL
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)
Copies the contents of the source SVssv
into the destination SVdsv
. The source SV may be destroyed if it is mortal, so don't use this function if the source SV needs to be reused. Does not handle 'set' magic on destination SV. Calls 'get' magic on source SV. Loosely speaking, it performs a copy-by-value, obliterating any previous content of the destination.
You probably want to use one of the assortment of wrappers, such asSvSetSV
,SvSetSV_nosteal
,SvSetMagicSV
andSvSetMagicSV_nosteal
.
voidsv_setsv(SV *dstr, SV *sstr)
Copies the contents of the source SVssv
into the destination SVdsv
. The source SV may be destroyed if it is mortal, so don't use this function if the source SV needs to be reused. Does not handle 'set' magic. Loosely speaking, it performs a copy-by-value, obliterating any previous content of the destination. If theflags
parameter has theSV_GMAGIC
bit set, willmg_get
onssv
if appropriate, else not. If theflags
parameter has theSV_NOSTEAL
bit set then the buffers of temps will not be stolen.sv_setsv
andsv_setsv_nomg
are implemented in terms of this function.
You probably want to use one of the assortment of wrappers, such asSvSetSV
,SvSetSV_nosteal
,SvSetMagicSV
andSvSetMagicSV_nosteal
.
This is the primary function for copying scalars, and most other copy-ish functions and macros use this underneath.
voidsv_setsv_flags(SV *dstr, SV *sstr, const I32 flags)
Likesv_setsv
, but also handles 'set' magic.
voidsv_setsv_mg(SV *const dstr, SV *const sstr)
Copies an unsigned integer into the given SV, upgrading first if necessary. Does not handle 'set' magic. See also"sv_setuv_mg"
.
voidsv_setuv(SV *const sv, const UV num)
Likesv_setuv
, but also handles 'set' magic.
voidsv_setuv_mg(SV *const sv, const UV u)
Test an SV for taintedness. UseSvTAINTED
instead.
boolsv_tainted(SV *const sv)
Returns true if the SV has a true value by Perl's rules. Use theSvTRUE
macro instead, which may callsv_true()
or may instead use an in-line version.
I32sv_true(SV *const sv)
Removes all magic of typetype
from an SV.
intsv_unmagic(SV *const sv, const int type)
Removes all magic of typetype
with the specifiedvtbl
from an SV.
intsv_unmagicext(SV *const sv, const int type, MGVTBL *vtbl)
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 ofnewSVrv
. Thecflags
argument can containSV_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"
.
voidsv_unref_flags(SV *const ref, const U32 flags)
Untaint an SV. UseSvTAINTED_off
instead.
voidsv_untaint(SV *const sv)
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 theSvUPGRADE
macro wrapper, which checks the type before callingsv_upgrade
, and hence does not croak. See also"svtype"
.
voidsv_upgrade(SV *const sv, svtype new_type)
Tells an SV to useptr
to find its string value. Normally the string is stored inside the SV, but sv_usepvn allows the SV to use an outside string.ptr
should point to memory that was allocated byNewx
. It must be the start of aNewx
-ed block of memory, and not a pointer to the middle of it (beware ofOOK
and copy-on-write), and not be from a non-Newx
memory allocator likemalloc
. The string length,len
, must be supplied. By default this function willRenew
(i.e. realloc, move) the memory pointed to byptr
, so that pointer should not be freed or used by the programmer after giving it tosv_usepvn
, and neither should any pointers from "behind" that pointer (e.g. ptr + 1) be used.
Ifflags & SV_SMAGIC
is true, will callSvSETMAGIC
. Ifflags
& SV_HAS_TRAILING_NUL> is true, thenptr[len]
must beNUL
, and the realloc will be skipped (i.e. the buffer is actually at least 1 byte longer thanlen
, and already meets the requirements for storing inSvPVX
).
voidsv_usepvn_flags(SV *const sv, char* ptr, const STRLEN len, const U32 flags)
NOTE: this function is experimental and may change or be removed without notice.
If the PV of the SV is an octet sequence in UTF-8 and contains a multiple-byte character, theSvUTF8
flag is turned on so that it looks like a character. If the PV contains only single-byte characters, theSvUTF8
flag stays off. Scans PV for validity and returns false if the PV is invalid UTF-8.
boolsv_utf8_decode(SV *const sv)
NOTE: this function is experimental and may change or be removed without notice.
Attempts 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, either returns false or, iffail_ok
is not true, croaks.
This is not a general purpose Unicode to byte encoding interface: use theEncode
extension for that.
boolsv_utf8_downgrade(SV *const sv, const bool fail_ok)
Converts the PV of an SV to UTF-8, but then turns theSvUTF8
flag off so that it looks like octets again.
voidsv_utf8_encode(SV *const sv)
Converts the PV of an SV to its UTF-8-encoded form. Forces the SV to string form if it is not already. Willmg_get
onsv
if appropriate. Always sets theSvUTF8
flag to avoid future validity checks even if the whole string is the same in UTF-8 as not. Returns the number of bytes in the converted string
This is not a general purpose byte encoding to Unicode interface: use the Encode extension for that.
STRLENsv_utf8_upgrade(SV *sv)
Converts the PV of an SV to its UTF-8-encoded form. Forces the SV to string form if it is not already. Always sets the SvUTF8 flag to avoid future validity checks even if all the bytes are invariant in UTF-8. Ifflags
hasSV_GMAGIC
bit set, willmg_get
onsv
if appropriate, else not.
Ifflags
hasSV_FORCE_UTF8_UPGRADE
set, this function assumes that the PV will expand when converted to UTF-8, and skips the extra work of checking for that. Typically this flag is used by a routine that has already parsed the string and found such characters, and passes this information on so that the work doesn't have to be repeated.
Returns the number of bytes in the converted string.
This is not a general purpose byte encoding to Unicode interface: use the Encode extension for that.
STRLENsv_utf8_upgrade_flags(SV *const sv, const I32 flags)
Likesv_utf8_upgrade_flags
, but has an additional parameterextra
, which is the number of unused bytes the string ofsv
is guaranteed to have free after it upon return. This allows the caller to reserve extra space that it intends to fill, to avoid extra grows.
sv_utf8_upgrade
,sv_utf8_upgrade_nomg
, andsv_utf8_upgrade_flags
are implemented in terms of this function.
Returns the number of bytes in the converted string (not including the spares).
STRLENsv_utf8_upgrade_flags_grow(SV *const sv, const I32 flags, STRLEN extra)
Likesv_utf8_upgrade
, but doesn't do magic onsv
.
STRLENsv_utf8_upgrade_nomg(SV *sv)
Processes its arguments likesv_catpvfn
called with a non-null C-style variable argument list, and appends the formatted to an SV. Does not handle 'set' magic. See"sv_vcatpvf_mg"
.
Usually used via its frontendsv_catpvf
.
voidsv_vcatpvf(SV *const sv, const char *const pat, va_list *const args)
voidsv_vcatpvfn(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const I32 svmax, bool *const maybe_tainted)
Processes its arguments likevsprintf
and appends the formatted output to an SV. Uses 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-styleva_list
argument list with a format string that uses argument reordering will yield an exception.
When running with taint checks enabled, indicates viamaybe_tainted
if results are untrustworthy (often due to the use of locales).
If called assv_vcatpvfn
or flags has theSV_GMAGIC
bit set, calls get magic.
Usually used via one of its frontendssv_vcatpvf
andsv_vcatpvf_mg
.
voidsv_vcatpvfn_flags(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const I32 svmax, bool *const maybe_tainted, const U32 flags)
Likesv_vcatpvf
, but also handles 'set' magic.
Usually used via its frontendsv_catpvf_mg
.
voidsv_vcatpvf_mg(SV *const sv, const char *const pat, va_list *const args)
Works likesv_vcatpvf
but copies the text into the SV instead of appending it. Does not handle 'set' magic. See"sv_vsetpvf_mg"
.
Usually used via its frontendsv_setpvf
.
voidsv_vsetpvf(SV *const sv, const char *const pat, va_list *const args)
Works likesv_vcatpvfn
but copies the text into the SV instead of appending it.
Usually used via one of its frontendssv_vsetpvf
andsv_vsetpvf_mg
.
voidsv_vsetpvfn(SV *const sv, const char *const pat, const STRLEN patlen, va_list *const args, SV **const svargs, const I32 svmax, bool *const maybe_tainted)
Likesv_vsetpvf
, but also handles 'set' magic.
Usually used via its frontendsv_setpvf_mg
.
voidsv_vsetpvf_mg(SV *const sv, const char *const pat, va_list *const args)
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for arrays. See"svtype".
Type flag for subroutines. See"svtype".
Type flag for formats. See"svtype".
Type flag for typeglobs. See"svtype".
Type flag for hashes. See"svtype".
Type flag for I/O objects. See"svtype".
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for scalars. See"svtype".
Type flag for regular expressions. See"svtype".
An enum of flags for Perl types. These are found in the filesv.h in thesvtype
enum. Test these flags with theSvTYPE
macro.
The types are:
SVt_NULLSVt_IVSVt_NVSVt_RVSVt_PVSVt_PVIVSVt_PVNVSVt_PVMGSVt_INVLISTSVt_REGEXPSVt_PVGVSVt_PVLVSVt_PVAVSVt_PVHVSVt_PVCVSVt_PVFMSVt_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 andSVt_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, checkingSvTYPE(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. IfSvFAKE(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 ofsubstr
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 ofSVt_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 forSVt_IV
, which exists for backward compatibility.)SVt_NV
can hold any of those or a double.SVt_PV
can only holdundef
or a string.SVt_PVIV
is a superset ofSVt_PV
andSVt_IV
.SVt_PVNV
is similar.SVt_PVMG
can hold anythingSVt_PVNV
can hold, but it can, but does not have to, be blessed or magical.
Returns a true SV ifb
is a true value, or a false SV ifb
is 0.
See also"PL_sv_yes"
and"PL_sv_no"
.
SV *boolSV(bool b)
A specialised variant ofcroak()
for emitting the usage message for xsubs
croak_xs_usage(cv, "eee_yow");
works out the package name and subroutine name fromcv
, and then callscroak()
. Hence ifcv
is&ouch::awk
, it would callcroak
as:
Perl_croak(aTHX_ "Usage: %"SVf"::%"SVf"(%s)", "ouch" "awk", "eee_yow");voidcroak_xs_usage(const CV *const cv, const char *const params)
Returns the SV of the specified Perl scalar.flags
are passed togv_fetchpv
. IfGV_ADD
is set and the Perl variable does not exist then it will be created. Ifflags
is zero and the variable does not exist then NULL is returned.
NOTE: the perl_ form of this function is deprecated.
SV*get_sv(const char *name, I32 flags)
Creates an RV wrapper for an SV. The reference count for the original SV is incremented.
SV*newRV_inc(SV* sv)
NOTE: this function is experimental and may change or be removed without notice.
Creates a new SV containing the pad name.
SV*newSVpadname(PADNAME *pn)
Creates a new SV and copies a string (which may containNUL
(\0
) characters) into it. Ifutf8
is true, callsSvUTF8_on
on the new SV. Implemented as a wrapper aroundnewSVpvn_flags
.
SV*newSVpvn_utf8(NULLOK const char* s, STRLEN len, U32 utf8)
Likesv_catpvn
but doesn't process magic.
voidsv_catpvn_nomg(SV* sv, const char* ptr, STRLEN len)
Likesv_catpv
but doesn't process magic.
voidsv_catpv_nomg(SV* sv, const char* ptr)
Likesv_catsv
but doesn't process magic.
voidsv_catsv_nomg(SV* dsv, SV* ssv)
Returns the length of the string which is in the SV. See"SvLEN"
.
STRLENSvCUR(SV* sv)
Set the current length of the string which is in the SV. See"SvCUR"
andSvIV_set
>.
voidSvCUR_set(SV* sv, STRLEN len)
Exactly like"sv_derived_from_pv", but doesn't take aflags
parameter.
boolsv_derived_from(SV* sv, const char *const name)
Exactly like"sv_derived_from_pvn", but takes a nul-terminated string instead of a string/length pair.
boolsv_derived_from_pv(SV* sv, const char *const name, U32 flags)
Returns a boolean indicating whether the SV is derived from the specified classat the C level. To check derivation at the Perl level, callisa()
as a normal Perl method.
Currently, the only significant value forflags
is SVf_UTF8.
boolsv_derived_from_pvn(SV* sv, const char *const name, const STRLEN len, U32 flags)
Exactly like"sv_derived_from_pvn", but takes the name string in the form of an SV instead of a string/length pair.
boolsv_derived_from_sv(SV* sv, SV *namesv, U32 flags)
Like"sv_does_pv", but doesn't take aflags
parameter.
boolsv_does(SV* sv, const char *const name)
Like"sv_does_sv", but takes a nul-terminated string instead of an SV.
boolsv_does_pv(SV* sv, const char *const name, U32 flags)
Like"sv_does_sv", but takes a string/length pair instead of an SV.
boolsv_does_pvn(SV* sv, const char *const name, const STRLEN len, U32 flags)
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.
boolsv_does_sv(SV* sv, SV* namesv, U32 flags)
Returns a pointer to the spot just after the last character in the string which is in the SV, where there is usually a trailingNUL
character (even though Perl scalars do not strictly require it). See"SvCUR"
. Access the character as*(SvEND(sv))
.
Warning: IfSvCUR
is equal toSvLEN
, thenSvEND
points to unallocated memory.
char*SvEND(SV* sv)
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.
U32SvGAMAGIC(SV* sv)
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 trailingNUL
character). Callssv_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 callsv_grow
if you are not sure of the type of SV.
char *SvGROW(SV* sv, STRLEN len)
Returns a U32 value indicating whether the SV contains an integer.
U32SvIOK(SV* sv)
Returns a boolean indicating whether the SV contains a signed integer.
boolSvIOK_notUV(SV* sv)
Unsets the IV status of an SV.
voidSvIOK_off(SV* sv)
Tells an SV that it is an integer.
voidSvIOK_on(SV* sv)
Tells an SV that it is an integer and disables all otherOK
bits.
voidSvIOK_only(SV* sv)
Tells an SV that it is an unsigned integer and disables all otherOK
bits.
voidSvIOK_only_UV(SV* sv)
Returns a U32 value indicating whether the SV contains an integer. Checks theprivate setting. UseSvIOK
instead.
U32SvIOKp(SV* sv)
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 be flagged as eitherSvUOK
orSVIOK
.
boolSvIOK_UV(SV* sv)
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).
U32SvIsCOW(SV* sv)
Returns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.
boolSvIsCOW_shared_hash(SV* sv)
Coerces the given SV to an integer and returns it. See"SvIVx"
for a version which guarantees to evaluatesv
only once.
IVSvIV(SV* sv)
LikeSvIV
but doesn't process magic.
IVSvIV_nomg(SV* sv)
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 toSvIVX
. With future Perls, however, it will be more efficient to useSvIV_set
instead of the lvalue assignment toSvIVX
.
voidSvIV_set(SV* sv, IV val)
Returns the raw value in the SV's IV slot, without checks or conversions. Only use when you are sureSvIOK
is true. See also"SvIV"
.
IVSvIVX(SV* sv)
Coerces the given SV to an integer and returns it. Guarantees to evaluatesv
only once. Only use this ifsv
is an expression with side effects, otherwise use the more efficientSvIV
.
IVSvIVx(SV* sv)
Returns the size of the string buffer in the SV, not including any part attributable toSvOOK
. See"SvCUR"
.
STRLENSvLEN(SV* sv)
Set the size of the string buffer for the SV. See"SvLEN"
.
voidSvLEN_set(SV* sv, STRLEN len)
Set the value of the MAGIC pointer insv
to val. See"SvIV_set"
.
voidSvMAGIC_set(SV* sv, MAGIC* val)
Returns a U32 value indicating whether the SV contains a number, integer or double.
U32SvNIOK(SV* sv)
Unsets the NV/IV status of an SV.
voidSvNIOK_off(SV* sv)
Returns a U32 value indicating whether the SV contains a number, integer or double. Checks theprivate setting. UseSvNIOK
instead.
U32SvNIOKp(SV* sv)
Returns a U32 value indicating whether the SV contains a double.
U32SvNOK(SV* sv)
Unsets the NV status of an SV.
voidSvNOK_off(SV* sv)
Tells an SV that it is a double.
voidSvNOK_on(SV* sv)
Tells an SV that it is a double and disables all other OK bits.
voidSvNOK_only(SV* sv)
Returns a U32 value indicating whether the SV contains a double. Checks theprivate setting. UseSvNOK
instead.
U32SvNOKp(SV* sv)
Coerce the given SV to a double and return it. See"SvNVx"
for a version which guarantees to evaluatesv
only once.
NVSvNV(SV* sv)
LikeSvNV
but doesn't process magic.
NVSvNV_nomg(SV* sv)
Set the value of the NV pointer insv
to val. See"SvIV_set"
.
voidSvNV_set(SV* sv, NV val)
Returns the raw value in the SV's NV slot, without checks or conversions. Only use when you are sureSvNOK
is true. See also"SvNV"
.
NVSvNVX(SV* sv)
Coerces the given SV to a double and returns it. Guarantees to evaluatesv
only once. Only use this ifsv
is an expression with side effects, otherwise use the more efficientSvNV
.
NVSvNVx(SV* sv)
Returns a U32 value indicating whether the value is defined. This is only meaningful for scalars.
U32SvOK(SV* sv)
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 aSvPV
. WhenSvOOK
is true, then the start of the allocated string buffer is actuallySvOOK_offset()
bytes beforeSvPVX
. This offset used to be stored inSvIVX
, but is now stored within the spare part of the buffer.
U32SvOOK(SV* sv)
Reads intolen
the offset fromSvPVX
back to the true start of the allocated buffer, which will be non-zero ifsv_chop
has been used to efficiently remove characters from start of the buffer. Implemented as a macro, which takes the address oflen
, which must be of typeSTRLEN
. Evaluatessv
more than once. Setslen
to 0 ifSvOOK(sv)
is false.
voidSvOOK_offset(NN SV*sv, STRLEN len)
Returns a U32 value indicating whether the SV contains a character string.
U32SvPOK(SV* sv)
Unsets the PV status of an SV.
voidSvPOK_off(SV* sv)
Tells an SV that it is a string.
voidSvPOK_on(SV* sv)
Tells an SV that it is a string and disables all otherOK
bits. Will also turn off the UTF-8 status.
voidSvPOK_only(SV* sv)
Tells an SV that it is a string and disables all otherOK
bits, and leaves the UTF-8 status as it was.
voidSvPOK_only_UTF8(SV* sv)
Returns a U32 value indicating whether the SV contains a character string. Checks theprivate setting. UseSvPOK
instead.
U32SvPOKp(SV* sv)
Returns a pointer to the string in the SV, or a stringified form of the SV if the SV does not contain a string. The SV may cache the stringified version becomingSvPOK
. Handles 'get' magic. Thelen
variable will be set to the length of the string (this is a macro, so don't use&len
). See also"SvPVx"
for a version which guarantees to evaluatesv
only once.
Note that there is no guarantee that the return value ofSvPV()
is equal toSvPVX(sv)
, or thatSvPVX(sv)
contains valid data, or that successive calls toSvPV(sv)
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 theSvPVX
field to be valid (for example, if you intend to write to it), then see"SvPV_force"
.
char*SvPV(SV* sv, STRLEN len)
LikeSvPV
, but convertssv
to byte representation first if necessary.
char*SvPVbyte(SV* sv, STRLEN len)
LikeSvPV_force
, but convertssv
to byte representation first if necessary.
char*SvPVbyte_force(SV* sv, STRLEN len)
LikeSvPV_nolen
, but convertssv
to byte representation first if necessary.
char*SvPVbyte_nolen(SV* sv)
LikeSvPV
, but convertssv
to byte representation first if necessary. Guarantees to evaluatesv
only once; use the more efficientSvPVbyte
otherwise.
char*SvPVbytex(SV* sv, STRLEN len)
LikeSvPV_force
, but convertssv
to byte representation first if necessary. Guarantees to evaluatesv
only once; use the more efficientSvPVbyte_force
otherwise.
char*SvPVbytex_force(SV* sv, STRLEN len)
LikeSvPV
but will force the SV into containing a string (SvPOK
), and only a string (SvPOK_only
), by hook or by crook. You need force if you are going to update theSvPVX
directly. Processes get magic.
Note that coercing an arbitrary scalar into a plain PV will potentially strip useful data from it. For example if the SV wasSvROK
, then the referent will have its reference count decremented, and the SV itself may be converted to anSvPOK
scalar with a string buffer containing a value such as"ARRAY(0x1234)"
.
char*SvPV_force(SV* sv, STRLEN len)
LikeSvPV_force
, but doesn't process get magic.
char*SvPV_force_nomg(SV* sv, STRLEN len)
LikeSvPV
but doesn't set a length variable.
char*SvPV_nolen(SV* sv)
LikeSvPV
but doesn't process magic.
char*SvPV_nomg(SV* sv, STRLEN len)
LikeSvPV_nolen
but doesn't process magic.
char*SvPV_nomg_nolen(SV* sv)
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 insv
to the Perl allocatedNUL
-terminated stringval
. 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 doSvOOK_off(sv)
and usesv_force_normal
orSvPV_force
(or check theSvIsCOW
flag) first to make sure this modification is safe. Then finally, if it is not a COW, callSvPV_free
to free the previous PV buffer.
voidSvPV_set(SV* sv, char* val)
LikeSvPV
, but convertssv
to UTF-8 first if necessary.
char*SvPVutf8(SV* sv, STRLEN len)
LikeSvPV
, but convertssv
to UTF-8 first if necessary. Guarantees to evaluatesv
only once; use the more efficientSvPVutf8
otherwise.
char*SvPVutf8x(SV* sv, STRLEN len)
LikeSvPV_force
, but convertssv
to UTF-8 first if necessary. Guarantees to evaluatesv
only once; use the more efficientSvPVutf8_force
otherwise.
char*SvPVutf8x_force(SV* sv, STRLEN len)
LikeSvPV_force
, but convertssv
to UTF-8 first if necessary.
char*SvPVutf8_force(SV* sv, STRLEN len)
LikeSvPV_nolen
, but convertssv
to UTF-8 first if necessary.
char*SvPVutf8_nolen(SV* sv)
Returns 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 this macro unless the SV's type >=SVt_PV
.
This is also used to store the name of an autoloaded subroutine in an XS AUTOLOAD routine. See"Autoloading with XSUBs" in perlguts.
char*SvPVX(SV* sv)
A version ofSvPV
which guarantees to evaluatesv
only once. Only use this ifsv
is an expression with side effects, otherwise use the more efficientSvPV
.
char*SvPVx(SV* sv, STRLEN len)
Returns the value of the object's reference count.
U32SvREFCNT(SV* sv)
Decrements the reference count of the given SV.sv
may beNULL
.
voidSvREFCNT_dec(SV* sv)
Same asSvREFCNT_dec
, but can only be used if you knowsv
is notNULL
. Since we don't have to check the NULLness, it's faster and smaller.
voidSvREFCNT_dec_NN(SV* sv)
Increments the reference count of the given SV, returning the SV.
All of the followingSvREFCNT_inc
* macros are optimized versions ofSvREFCNT_inc
, and can be replaced withSvREFCNT_inc
.
SV*SvREFCNT_inc(SV* sv)
Same asSvREFCNT_inc
, but can only be used if you knowsv
is notNULL
. Since we don't have to check the NULLness, it's faster and smaller.
SV*SvREFCNT_inc_NN(SV* sv)
Same asSvREFCNT_inc
, but can only be used with expressions without side effects. Since we don't have to store a temporary value, it's faster.
SV*SvREFCNT_inc_simple(SV* sv)
Same asSvREFCNT_inc_simple
, but can only be used if you knowsv
is notNULL
. Since we don't have to check the NULLness, it's faster and smaller.
SV*SvREFCNT_inc_simple_NN(SV* sv)
Same asSvREFCNT_inc_simple
, but can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
voidSvREFCNT_inc_simple_void(SV* sv)
Same asSvREFCNT_inc
, but can only be used if you don't need the return value, and you know thatsv
is notNULL
. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
voidSvREFCNT_inc_simple_void_NN(SV* sv)
Same asSvREFCNT_inc
, but can only be used if you don't need the return value. The macro doesn't need to return a meaningful value.
voidSvREFCNT_inc_void(SV* sv)
Same asSvREFCNT_inc
, but can only be used if you don't need the return value, and you know thatsv
is notNULL
. The macro doesn't need to return a meaningful value, or check for NULLness, so it's smaller and faster.
voidSvREFCNT_inc_void_NN(SV* sv)
Dump the contents of all SVs not yet freed (debugging aid).
voidsv_report_used()
Tests if the SV is an RV.
U32SvROK(SV* sv)
Unsets the RV status of an SV.
voidSvROK_off(SV* sv)
Tells an SV that it is an RV.
voidSvROK_on(SV* sv)
Dereferences an RV to return the SV.
SV*SvRV(SV* sv)
Set the value of the RV pointer insv
to val. See"SvIV_set"
.
voidSvRV_set(SV* sv, SV* val)
Likesv_setsv
but doesn't process magic.
voidsv_setsv_nomg(SV* dsv, SV* ssv)
Returns the stash of the SV.
HV*SvSTASH(SV* sv)
Set the value of the STASH pointer insv
to val. See"SvIV_set"
.
voidSvSTASH_set(SV* sv, HV* val)
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.
voidSvTAINT(SV* sv)
Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.
boolSvTAINTED(SV* sv)
Untaints an SV. Bevery 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.
voidSvTAINTED_off(SV* sv)
Marks an SV as tainted if tainting is enabled.
voidSvTAINTED_on(SV* sv)
Returns a boolean indicating whether Perl would evaluate the SV as true or false. See"SvOK"
for a defined/undefined test. Handles 'get' magic unless the scalar is alreadySvPOK
,SvIOK
orSvNOK
(the public, not the private flags).
boolSvTRUE(SV* sv)
Returns a boolean indicating whether Perl would evaluate the SV as true or false. See"SvOK"
for a defined/undefined test. Does not handle 'get' magic.
boolSvTRUE_nomg(SV* sv)
Returns the type of the SV. See"svtype"
.
svtypeSvTYPE(SV* sv)
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 be flagged as eitherSvUOK
orSVIOK
.
boolSvUOK(SV* sv)
Used to upgrade an SV to a more complex form. Usessv_upgrade
to perform the upgrade if necessary. See"svtype"
.
voidSvUPGRADE(SV* sv, svtype type)
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 thisafter a call toSvPV()
or one of its variants, in case any call to string overloading updates the internal flag.
If you want to take into account thebytes pragma, use"DO_UTF8"
instead.
U32SvUTF8(SV* sv)
Likesv_utf8_upgrade
, but doesn't do magic onsv
.
STRLENsv_utf8_upgrade_nomg(NN SV *sv)
Unsets the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
voidSvUTF8_off(SV *sv)
Turn on the UTF-8 status of an SV (the data is not changed, just the flag). Do not use frivolously.
voidSvUTF8_on(SV *sv)
Coerces the given SV to an unsigned integer and returns it. See"SvUVx"
for a version which guarantees to evaluatesv
only once.
UVSvUV(SV* sv)
LikeSvUV
but doesn't process magic.
UVSvUV_nomg(SV* sv)
Set the value of the UV pointer insv
to val. See"SvIV_set"
.
voidSvUV_set(SV* sv, UV val)
Returns the raw value in the SV's UV slot, without checks or conversions. Only use when you are sureSvIOK
is true. See also"SvUV"
.
UVSvUVX(SV* sv)
Coerces the given SV to an unsigned integer and returns it. Guarantees to evaluatesv
only once. Only use this ifsv
is an expression with side effects, otherwise use the more efficientSvUV
.
UVSvUVx(SV* sv)
Returns a boolean indicating whether the SV contains a v-string.
boolSvVOK(SV* sv)
"Unicode Support" in perlguts has an introduction to this API.
See also"Character classification", and"Character case changing". Various functions outside this section also work specially with Unicode. Search for the string "utf8" in this document.
Compares the sequence of characters (stored as octets) inb
,blen
with the sequence of characters (stored as UTF-8) inu
,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.
intbytes_cmp_utf8(const U8 *b, STRLEN blen, const U8 *u, STRLEN ulen)
NOTE: this function is experimental and may change or be removed without notice.
Converts a strings
of lengthlen
from UTF-8 into native byte encoding. Unlike"utf8_to_bytes" but like"bytes_to_utf8", returns a pointer to the newly-created string, and updateslen
to contain the new length. Returns the original string if no conversion occurs,len
is unchanged. Do nothing ifis_utf8
points to 0. Setsis_utf8
to 0 ifs
is converted or consisted entirely of characters that are invariant in UTF-8 (i.e., US-ASCII on non-EBCDIC machines).
U8*bytes_from_utf8(const U8 *s, STRLEN *len, bool *is_utf8)
NOTE: this function is experimental and may change or be removed without notice.
Converts a strings
of lengthlen
bytes from the native encoding into UTF-8. Returns a pointer to the newly-created string, and setslen
to reflect the new length in bytes.
ANUL
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 *len)
Returns a bool giving whether or not the PV insv
is to be treated as being encoded in UTF-8.
You should use thisafter a call toSvPV()
or one of its variants, in case any call to string overloading updates the internal UTF-8 encoding flag.
boolDO_UTF8(SV* sv)
Returns true if the leading portions of the stringss1
ands2
(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.
Ifu1
is true, the strings1
is assumed to be in UTF-8-encoded Unicode; otherwise it is assumed to be in native 8-bit encoding. Correspondingly foru2
with respect tos2
.
If the byte lengthl1
is non-zero, it says how far intos1
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 forl2
with respect tos2
.
Ifpe1
is non-NULL
and the pointer it points to is notNULL
, that pointer is considered an end pointer to the position 1 byte past the maximum point ins1
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 pastpe1
). This means that if bothl1
andpe1
are specified, andpe1
is less thans1
+l1
, the match will never be successful because it can never get as far as its goal (and in fact is asserted against). Correspondingly forpe2
with respect tos2
.
At least one ofs1
ands2
must have a goal (at least one ofl1
andl2
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, ifpe1
is non-NULL
, it will be set to point to the beginning of thenext character ofs1
beyond what was matched. Correspondingly forpe2
ands2
.
For case-insensitiveness, the "casefolding" of Unicode is used instead of upper/lowercasing both the characters, seehttp://www.unicode.org/unicode/reports/tr21/ (Case Mappings).
I32foldEQ_utf8(const char *s1, char **pe1, UV l1, bool u1, const char *s2, char **pe2, UV l2, bool u2)
This is a misleadingly-named synonym for"is_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, sois_invariant_string
is preferred.
boolis_ascii_string(const U8 *s, STRLEN len)
Returns true iff the firstlen
bytes of the strings
are the same regardless of the UTF-8 encoding of the string (or UTF-EBCDIC encoding on EBCDIC machines). That is, 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 and\c?
(which isn't in the ASCII range on EBCDIC).
Iflen
is 0, it will be calculated usingstrlen(s)
, (which means if you use this option, thats
can't have embeddedNUL
characters and has to have a terminatingNUL
byte).
See also"is_utf8_string"(),"is_utf8_string_loclen"(), and"is_utf8_string_loc"().
boolis_invariant_string(const U8 *s, STRLEN len)
Returns true if the firstlen
bytes of strings
form a valid UTF-8 string, false otherwise. Iflen
is 0, it will be calculated usingstrlen(s)
(which means if you use this option, thats
can't have embeddedNUL
characters and has to have a terminatingNUL
byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
See also"is_invariant_string"(),"is_utf8_string_loclen"(), and"is_utf8_string_loc"().
boolis_utf8_string(const U8 *s, STRLEN len)
Like"is_utf8_string" but stores the location of the failure (in the case of "utf8ness failure") or the locations
+len
(in the case of "utf8ness success") in theep
.
See also"is_utf8_string_loclen"() and"is_utf8_string"().
boolis_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)
Like"is_utf8_string"() but stores the location of the failure (in the case of "utf8ness failure") or the locations
+len
(in the case of "utf8ness success") in theep
, and the number of UTF-8 encoded characters in theel
.
See also"is_utf8_string_loc"() and"is_utf8_string"().
boolis_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
Returns the number of bytes beginning ats
which form a legal UTF-8 (or UTF-EBCDIC) encoded character, looking no further thane - s
bytes intos
. Returns 0 if the sequence starting ats
throughe - 1
is not well-formed UTF-8.
Note that an INVARIANT character (i.e. ASCII on non-EBCDIC machines) is a valid UTF-8 character.
STRLENisUTF8_CHAR(const U8 *s, const U8 *e)
Build to the scalardsv
a displayable version of the stringspv
, lengthlen
, the displayable version being at mostpvlim
bytes long (if longer, the rest is truncated and"..."
will be appended).
Theflags
argument can haveUNI_DISPLAY_ISPRINT
set to displayisPRINT()
able characters as themselves,UNI_DISPLAY_BACKSLASH
to display the\\[nrfta\\]
as the backslashed versions (like"\n"
) (UNI_DISPLAY_BACKSLASH
is preferred overUNI_DISPLAY_ISPRINT
for"\\"
).UNI_DISPLAY_QQ
(and its aliasUNI_DISPLAY_REGEX
) have bothUNI_DISPLAY_BACKSLASH
andUNI_DISPLAY_ISPRINT
turned on.
The pointer to the PV of thedsv
is returned.
See also"sv_uni_display".
char*pv_uni_display(SV *dsv, const U8 *spv, STRLEN len, STRLEN pvlim, UV flags)
encoding
is assumed to be anEncode
object, the PV ofssv
is assumed to be octets in that encoding and decoding the input starts from the position which(PV + *offset)
pointed to.dsv
will be concatenated with the decoded UTF-8 string fromssv
. Decoding will terminate when the stringtstr
appears in decoding output or the input ends on the PV ofssv
. The value whichoffset
points will be modified to the last input position onssv
.
Returns TRUE if the terminator was found, else returns FALSE.
boolsv_cat_decode(SV* dsv, SV *encoding, SV *ssv, int *offset, char* tstr, int tlen)
encoding
is assumed to be anEncode
object, on entry the PV ofsv
is assumed to be octets in that encoding, andsv
will be converted into Unicode (and UTF-8).
Ifsv
already is UTF-8 (or if it is notPOK
), or ifencoding
is not a reference, nothing is done tosv
. Ifencoding
is not anEncode::XS
Encoding object, bad things will happen. (Seecpan/Encode/encoding.pm andEncode.)
The PV ofsv
is returned.
char*sv_recode_to_utf8(SV* sv, SV *encoding)
Build to the scalardsv
a displayable version of the scalarsv
, the displayable version being at mostpvlim
bytes long (if longer, the rest is truncated and "..." will be appended).
Theflags
argument is as in"pv_uni_display"().
The pointer to the PV of thedsv
is returned.
char*sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim, UV flags)
DEPRECATED! It is planned to remove this function from a future release of Perl. Do not use it for new code; remove it from existing code.
Instead use the appropriate one of"toUPPER_utf8","toTITLE_utf8","toLOWER_utf8", or"toFOLD_utf8".
p
contains the pointer to the UTF-8 string encoding the character that is being converted. This routine assumes that the character atp
is well-formed.
ustrp
is a pointer to the character buffer to put the conversion result to.lenp
is a pointer to the length of the result.
swashp
is a pointer to the swash to use.
Both the special and normal mappings are stored inlib/unicore/To/Foo.pl, and loaded bySWASHNEW
, usinglib/utf8_heavy.pl.special
(usually, but not always, a multicharacter mapping), is tried first.
special
is a string, normallyNULL
or""
.NULL
means to not use any special mappings;""
means to use the special mappings. Values other than these two are treated as the name of the hash containing the special mappings, like"utf8::ToSpecLower"
.
normal
is a string like"ToLower"
which means the swash%utf8::ToLower
.
Code points above the platform'sIV_MAX
will raise a deprecation warning, unless those are turned off.
UVto_utf8_case(const U8 *p, U8* ustrp, STRLEN *lenp, SV **swashp, const char *normal, const char *special)
Instead use"toFOLD_utf8".
UVto_utf8_fold(const U8 *p, U8* ustrp, STRLEN *lenp)
Instead use"toLOWER_utf8".
UVto_utf8_lower(const U8 *p, U8* ustrp, STRLEN *lenp)
Instead use"toTITLE_utf8".
UVto_utf8_title(const U8 *p, U8* ustrp, STRLEN *lenp)
Instead use"toUPPER_utf8".
UVto_utf8_upper(const U8 *p, U8* ustrp, STRLEN *lenp)
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 strings
, which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer thancurlen
bytes;*retlen
(ifretlen
isn't NULL) will be set to the length, in bytes, of that character.
The value offlags
determines the behavior whens
does not point to a well-formed UTF-8 character. Ifflags
is 0, when a malformation is found, zero is returned and*retlen
is set so that (s
+*retlen
) is the next possible position ins
that could begin a non-malformed character. Also, if UTF-8 warnings haven't been lexically disabled, a warning is raised.
Various ALLOW flags can be set inflags
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. Seeutf8.h for the list of such flags. For allowed 0 length strings, this function returns 0; for allowed overlong sequences, the computed code point is returned; for all other allowed malformations, the Unicode REPLACEMENT CHARACTER is returned, as these have no determinable reasonable value.
TheUTF8_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 setretlen
to-1
(cast toSTRLEN
) and return zero.
Note that this API requires disambiguation between successful decoding aNUL
character, and an error return (unless theUTF8_CHECK_ONLY
flag is set), as in both cases, 0 is returned. To disambiguate, upon a zero return, see if the first byte ofs
is 0 as well. If so, the input was aNUL
; if not, the input had an 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. Ifflags
containsUTF8_DISALLOW_ILLEGAL_INTERCHANGE
, all three classes are treated as malformations and handled as such. The flagsUTF8_DISALLOW_SURROGATE
,UTF8_DISALLOW_NONCHAR
, andUTF8_DISALLOW_SUPER
(meaning above the legal Unicode maximum) can be set to disallow these categories individually.
The flagsUTF8_WARN_ILLEGAL_INTERCHANGE
,UTF8_WARN_SURROGATE
,UTF8_WARN_NONCHAR
, andUTF8_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 ifUTF8_CHECK_ONLY
is also specified.)
It is now deprecated to have very high code points (aboveIV_MAX
on the platforms) and this function will raise a deprecation warning for these (unless such warnings are turned off). This value, is typically 0x7FFF_FFFF (2**31 -1) in a 32-bit word.
Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard, so using them is more problematic than other above-Unicode code points. Perl invented an extension to UTF-8 to represent the ones above 2**36-1, so it is likely that non-Perl languages will not be able to read files that contain these that written by the perl interpreter; 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. These are theUTF8_WARN_ABOVE_31_BIT
andUTF8_DISALLOW_ABOVE_31_BIT
flags. These are entirely independent from the deprecation warning for code points aboveIV_MAX
. On 32-bit machines, it will eventually be forbidden to have any code point that needs more than 31 bits to represent. When that happens, effectively theUTF8_DISALLOW_ABOVE_31_BIT
flag will always be set on 32-bit machines. (Of courseUTF8_DISALLOW_SUPER
will treat all above-Unicode code points, including these, as malformations; andUTF8_WARN_SUPER
warns on these.)
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. The flagsUTF8_WARN_ABOVE_31_BIT
andUTF8_DISALLOW_ABOVE_31_BIT
have the same function as on ASCII platforms, warning and disallowing 2**31 and higher.
All other code points corresponding to Unicode characters, including private use and those yet to be assigned, are never considered malformed and never warn.
UVutf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen, U32 flags)
Instead use"utf8_to_uvchr_buf", or rarely,"utf8n_to_uvchr".
This function was useful for code that wanted to handle both EBCDIC and ASCII platforms with Unicode properties, but starting in Perl v5.20, the distinctions between the platforms have mostly been made invisible to most code, so this function is quite unlikely to be what you want. If you do need this precise functionality, use insteadNATIVE_TO_UNI(utf8_to_uvchr_buf(...))
orNATIVE_TO_UNI(utf8n_to_uvchr(...))
.
UVutf8n_to_uvuni(const U8 *s, STRLEN curlen, STRLEN *retlen, U32 flags)
returns the number of bytes in the UTF-8 encoded character whose first (perhaps only) byte is pointed to bys
.
STRLENUTF8SKIP(char* s)
Returns the number of UTF-8 characters between the UTF-8 pointersa
andb
.
WARNING: use only if you *know* that the pointers point inside the same UTF-8 buffer.
IVutf8_distance(const U8 *a, const U8 *b)
Return the UTF-8 pointers
displaced byoff
characters, either forward or backward.
WARNING: do not use the following unless you *know*off
is within the UTF-8 data pointed to bys
*and* that on entrys
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)
Return the length of the UTF-8 char encoded strings
in characters. Stops ate
(inclusive). Ife < s
or if the scan would end up paste
, croaks.
STRLENutf8_length(const U8* s, const U8 *e)
NOTE: this function is experimental and may change or be removed without notice.
Converts a strings
of lengthlen
from UTF-8 into native byte encoding. Unlike"bytes_to_utf8", this over-writes the original string, and updateslen
to contain the new length. Returns zero on failure, settinglen
to -1.
If you need a copy of the string, see"bytes_from_utf8".
U8*utf8_to_bytes(U8 *s, STRLEN *len)
Returns the native code point of the first character in the strings
which is assumed to be in UTF-8 encoding;send
points to 1 beyond the end ofs
.*retlen
will be set to the length, in bytes, of that character.
Ifs
does not point to a well-formed UTF-8 character and UTF8 warnings are enabled, zero is returned and*retlen
is set (ifretlen
isn'tNULL
) 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 (ifretlen
isn'tNULL
) so that (s
+*retlen
) is the next possible position ins
that could begin a non-malformed character. See"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
Code points above the platform'sIV_MAX
will raise a deprecation warning, unless those are turned off.
UVutf8_to_uvchr_buf(const U8 *s, const U8 *send, STRLEN *retlen)
DEPRECATED! It is planned to remove this function from a future release of Perl. Do not use it for new code; remove it from existing code.
Only in very rare circumstances should code need to be dealing in Unicode (as opposed to native) code points. In those few cases, useNATIVE_TO_UNI(utf8_to_uvchr_buf(...))
instead.
Returns the Unicode (not-native) code point of the first character in the strings
which is assumed to be in UTF-8 encoding;send
points to 1 beyond the end ofs
.retlen
will be set to the length, in bytes, of that character.
Ifs
does not point to a well-formed UTF-8 character and UTF8 warnings are enabled, zero is returned and*retlen
is set (ifretlen
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 (ifretlen
isn't NULL) so that (s
+*retlen
) is the next possible position ins
that could begin a non-malformed character. See"utf8n_to_uvchr" for details on when the REPLACEMENT CHARACTER is returned.
Code points above the platform'sIV_MAX
will raise a deprecation warning, unless those are turned off.
UVutf8_to_uvuni_buf(const U8 *s, const U8 *send, STRLEN *retlen)
returns the number of bytes required to represent the code pointcp
when encoded as UTF-8.cp
is a native (ASCII or EBCDIC) code point if less than 255; a Unicode code point otherwise.
STRLENUVCHR_SKIP(UV cp)
Adds the UTF-8 representation of the native code pointuv
to the end of the stringd
;d
should have at leastUVCHR_SKIP(uv)+1
(up toUTF8_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 UV as input, but very high code points (aboveIV_MAX
on the platform) will raise a deprecation warning. This 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)
Adds the UTF-8 representation of the native code pointuv
to the end of the stringd
;d
should have at leastUVCHR_SKIP(uv)+1
(up toUTF8_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;
Ifflags
is 0, this function accepts any UV as input, but very high code points (aboveIV_MAX
for the platform) will raise a deprecation warning. This is typically 0x7FFF_FFFF in a 32-bit word.
Specifyingflags
can further restrict what is allowed and not warned on, as follows:
Ifuv
is a Unicode surrogate code point andUNICODE_WARN_SURROGATE
is set, the function will raise a warning, provided UTF8 warnings are enabled. If insteadUNICODE_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, theUNICODE_WARN_NONCHAR
andUNICODE_DISALLOW_NONCHAR
flags affect how the function handles a Unicode non-character.
And likewise, theUNICODE_WARN_SUPER
andUNICODE_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 flagUNICODE_WARN_ILLEGAL_INTERCHANGE
selects all three of the above WARN flags; andUNICODE_DISALLOW_ILLEGAL_INTERCHANGE
selects all three DISALLOW flags.
Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard, so using them is more problematic than other above-Unicode code points. Perl invented an extension to UTF-8 to represent the ones above 2**36-1, so it is likely that non-Perl languages will not be able to read files that contain these that written by the perl interpreter; 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. These are theUNICODE_WARN_ABOVE_31_BIT
andUNICODE_DISALLOW_ABOVE_31_BIT
flags. These are entirely independent from the deprecation warning for code points aboveIV_MAX
. On 32-bit machines, it will eventually be forbidden to have any code point that needs more than 31 bits to represent. When that happens, effectively theUNICODE_DISALLOW_ABOVE_31_BIT
flag will always be set on 32-bit machines. (Of courseUNICODE_DISALLOW_SUPER
will treat all above-Unicode code points, including these, as malformations; andUNICODE_WARN_SUPER
warns on these.)
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. The flagsUNICODE_WARN_ABOVE_31_BIT
andUNICODE_DISALLOW_ABOVE_31_BIT
have the same function as on ASCII platforms, warning and disallowing 2**31 and higher.
U8*uvchr_to_utf8_flags(U8 *d, UV uv, UV flags)
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Instead,Almost all code should use"uvchr_to_utf8" or"uvchr_to_utf8_flags".
This function is like them, but the input is a strict Unicode (as opposed to native) code point. Only in very rare circumstances should code not be using the native code point.
For details, see the description for"uvchr_to_utf8_flags".
U8*uvoffuni_to_utf8_flags(U8 *d, UV uv, UV flags)
Instead you almost certainly want to use"uvchr_to_utf8" or"uvchr_to_utf8_flags".
This function is a deprecated synonym for"uvoffuni_to_utf8_flags", which itself, while not deprecated, should be used only in isolated circumstances. These functions were useful for code that wanted to handle both EBCDIC and ASCII platforms with Unicode properties, but starting in Perl v5.20, the distinctions between the platforms have mostly been made invisible to most code, so this function is quite unlikely to be what you want.
U8*uvuni_to_utf8_flags(U8 *d, UV uv, UV flags)
xsubpp
andxsubpp
internal functionsUsed byxsubpp
to hook up XSUBs as Perl subs. Adds Perl prototypes to the subs.
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;
The version identifier for an XS module. This is usually handled automatically byExtUtils::MakeMaker
. See"XS_VERSION_BOOTCHECK"
.
Macro to verify that a PM module's$VERSION
variable matches the XS module'sXS_VERSION
variable. This is usually handled automatically byxsubpp
. See"The VERSIONCHECK: Keyword" in perlxs.
XS_VERSION_BOOTCHECK;
This is an XS interface to Perl'sdie
function.
Take a sprintf-style format pattern and argument list. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message will be used as an exception, by default returning control to the nearest enclosingeval
, but subject to modification by a$SIG{__DIE__}
handler. In any case, thecroak
function never returns normally.
For historical reasons, ifpat
is null then the contents ofERRSV
($@
) will be used as an error message or object instead of building an error message from arguments. If you want to throw a non-string object, or build an error message in an SV yourself, it is preferable to use the"croak_sv" function, which does not involve clobberingERRSV
.
voidcroak(const char *pat, ...)
Exactly equivalent toPerl_croak(aTHX_ "%s", PL_no_modify)
, but generates terser object code than usingPerl_croak
. Less code used on exception code paths reduces CPU cache pressure.
voidcroak_no_modify()
This is an XS interface to Perl'sdie
function.
baseex
is the error message or object. If it is a reference, it will be used as-is. Otherwise it is used as a string, and if it does not end with a newline then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message or object will be used as an exception, by default returning control to the nearest enclosingeval
, but subject to modification by a$SIG{__DIE__}
handler. In any case, thecroak_sv
function never returns normally.
To die with a simple string message, the"croak" function may be more convenient.
voidcroak_sv(SV *baseex)
Behaves the same as"croak", except for the return type. It should be used only where theOP *
return type is required. The function never actually returns.
OP *die(const char *pat, ...)
Behaves the same as"croak_sv", except for the return type. It should be used only where theOP *
return type is required. The function never actually returns.
OP *die_sv(SV *baseex)
This is an XS interface to Perl'sdie
function.
pat
andargs
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 enclosingeval
, but subject to modification by a$SIG{__DIE__}
handler. In any case, thecroak
function never returns normally.
For historical reasons, ifpat
is null then the contents ofERRSV
($@
) 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 clobberingERRSV
.
voidvcroak(const char *pat, va_list *args)
This is an XS interface to Perl'swarn
function.
pat
andargs
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 or object will by default be written to standard error, but this is subject to modification by a$SIG{__WARN__}
handler.
Unlike with"vcroak",pat
is not permitted to be null.
voidvwarn(const char *pat, va_list *args)
This is an XS interface to Perl'swarn
function.
Take a sprintf-style format pattern and argument list. These are used to generate a string message. If the message does not end with a newline, then it will be extended with some indication of the current location in the code, as described for"mess_sv".
The error message or object will by default be written to standard error, but this is subject to modification by a$SIG{__WARN__}
handler.
Unlike with"croak",pat
is not permitted to be null.
voidwarn(const char *pat, ...)
This is an XS interface to Perl'swarn
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.
voidwarn_sv(SV *baseex)
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 toperl5-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.
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.
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The Perl documentation is maintained by the Perl 5 Porters in the development of Perl. Please contact them via thePerl issue tracker, themailing list, orIRC to report any issues with the contents or format of the documentation.