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. NULL is also returned ifkey is out of range.
Perl equivalent:splice(@myarray, $key, 1, undef) (with thesplice in void context ifG_DISCARD is present).
SV*av_delete(AV *av, SSize_t key, I32 flags)Returns true if the element indexed bykey has been initialized.
This relies on the fact that uninitialized array elements are set toNULL.
Perl equivalent:exists($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[$key].
SV**av_fetch(AV *av, SSize_t key, I32 lval)Same asav_top_index() orav_tindex().
intAvFILL(AV* av)Set the highest index in the array to the given number, equivalent to Perl's$#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, $val;.
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:splice(@myarray, $key, 1, $val).
See"Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how to use this function on tied arrays.
SV**av_store(AV *av, SSize_t key, SV *val)Same asav_top_index().
intav_tindex(AV* av)Returns the highest index in the array. The number of elements in the array isav_top_index(av) + 1. Returns -1 if the array is empty.
The Perl equivalent for this is$#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.
Perl equivalent:unshift @myarray, ((undef) x $num);
voidav_unshift(AV *av, SSize_t num)Returns the AV of the specified Perl global or package array with the given name (so it won't work on lexical variables).flags are passed togv_fetchpv. IfGV_ADD is set and the Perl variable does not exist then it will be created. Ifflags is zero and the variable does not exist then NULL is returned.
Perl equivalent:@{"$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()In-place sort an array of SV pointers with the given comparison routine.
Currently this always uses mergesort. See"sortsv_flags" for a more flexible routine.
voidsortsv(SV** array, size_t num_elts, SVCOMPARE_t cmp)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, volatile I32 flags)Opening bracket on a callback. See"LEAVE" andperlcall.
ENTER;Same as"ENTER", but when debugging is enabled it also associates the given literal string with the new scope.
ENTER_with_name(name);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;Same as"LEAVE", but when debugging is enabled it first checks that the scope has the given name.name must be a literal string.
LEAVE_with_name(name);Opening bracket for temporaries on a callback. See"FREETMPS" andperlcall.
SAVETMPS;Perl uses "full" Unicode case mappings. This means that converting a single character to another case may result in a sequence of more than one character. For example, the uppercase ofß (LATIN SMALL LETTER SHARP S) is the two character sequenceSS. This presents some complications The lowercase of all characters in the range 0..255 is a single character, and thus"toLOWER_L1" is furnished. But,toUPPER_L1 can't exist, as it couldn't return a valid result for all legal inputs. Instead"toUPPER_uvchr" has an API that does allow every possible legal result to be returned.) Likewise no other function that is crippled by not being able to give the correct results for the full range of possible inputs has been implemented here.
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)This is like"toFOLD_utf8_safe", but doesn't have thee parameter The function therefore can't check if it is reading beyond the end of the string. Starting in Perl v5.30, it will take thee parameter, becoming a synonym fortoFOLD_utf8_safe. At that time every program that uses it will have to be changed to successfully compile. In the meantime, the first runtime call totoFOLD_utf8 from each call point in the program will raise a deprecation warning, enabled by default. You can convert your program now to usetoFOLD_utf8_safe, and avoid the warnings, and get an extra measure of protection, or you can wait until v5.30, when you'll be forced to add thee parameter.
UVtoFOLD_utf8(U8* p, U8* s, STRLEN* lenp)Converts the first UTF-8 encoded character in the sequence starting atp and extending no further thane - 1 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 atthe top of this section, that there may be more).
The suffix_safe in the function's name indicates that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UVtoFOLD_utf8_safe(U8* p, U8* e, 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 atthe top of this section, 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)This is like"toLOWER_utf8_safe", but doesn't have thee parameter The function therefore can't check if it is reading beyond the end of the string. Starting in Perl v5.30, it will take thee parameter, becoming a synonym fortoLOWER_utf8_safe. At that time every program that uses it will have to be changed to successfully compile. In the meantime, the first runtime call totoLOWER_utf8 from each call point in the program will raise a deprecation warning, enabled by default. You can convert your program now to usetoLOWER_utf8_safe, and avoid the warnings, and get an extra measure of protection, or you can wait until v5.30, when you'll be forced to add thee parameter.
UVtoLOWER_utf8(U8* p, U8* s, STRLEN* lenp)Converts the first UTF-8 encoded character in the sequence starting atp and extending no further thane - 1 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 atthe top of this section, that there may be more).
The suffix_safe in the function's name indicates that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UVtoLOWER_utf8_safe(U8* p, U8* e, 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 atthe top of this section, 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)This is like"toLOWER_utf8_safe", but doesn't have thee parameter The function therefore can't check if it is reading beyond the end of the string. Starting in Perl v5.30, it will take thee parameter, becoming a synonym fortoTITLE_utf8_safe. At that time every program that uses it will have to be changed to successfully compile. In the meantime, the first runtime call totoTITLE_utf8 from each call point in the program will raise a deprecation warning, enabled by default. You can convert your program now to usetoTITLE_utf8_safe, and avoid the warnings, and get an extra measure of protection, or you can wait until v5.30, when you'll be forced to add thee parameter.
UVtoTITLE_utf8(U8* p, U8* s, STRLEN* lenp)Converts the first UTF-8 encoded character in the sequence starting atp and extending no further thane - 1 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 atthe top of this section, that there may be more).
The suffix_safe in the function's name indicates that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UVtoTITLE_utf8_safe(U8* p, U8* e, 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 atthe top of this section, 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)This is like"toUPPER_utf8_safe", but doesn't have thee parameter The function therefore can't check if it is reading beyond the end of the string. Starting in Perl v5.30, it will take thee parameter, becoming a synonym fortoUPPER_utf8_safe. At that time every program that uses it will have to be changed to successfully compile. In the meantime, the first runtime call totoUPPER_utf8 from each call point in the program will raise a deprecation warning, enabled by default. You can convert your program now to usetoUPPER_utf8_safe, and avoid the warnings, and get an extra measure of protection, or you can wait until v5.30, when you'll be forced to add thee parameter.
UVtoUPPER_utf8(U8* p, U8* s, STRLEN* lenp)Converts the first UTF-8 encoded character in the sequence starting atp and extending no further thane - 1 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 atthe top of this section, that there may be more).
The suffix_safe in the function's name indicates that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return the REPLACEMENT CHARACTER, at the discretion of the implementation, and subject to change in future releases.
UVtoUPPER_utf8_safe(U8* p, U8* e, 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 atthe top of this section, 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". This variant is used to emphasize by its name that only ASCII-range characters can return TRUE.
VariantisFOO_L1 imposes the Latin-1 (or EBCDIC equivalent) character set onto the platform. That is, the code points that are ASCII are unaffected, since ASCII is a subset of Latin-1. But the non-ASCII code points are treated as if they are Latin-1 characters. For example,isWORDCHAR_L1() will return true when called with the code point 0xDF, which is a word character in both ASCII and EBCDIC (though it represents different characters in each).
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_safe is likeisFOO_uvchr, but is used for UTF-8 encoded strings. Each call classifies one character, even if the string contains many. This variant takes two parameters. The first,p, is a pointer to the first byte of the character to be classified. (Recall that it may take more than one byte to represent a character in UTF-8 strings.) The second parameter,e, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. The suffix_safe in the function's name indicates that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
VariantisFOO_utf8 is likeisFOO_utf8_safe, but takes just a single parameter,p, which has the same meaning as the corresponding parameter does inisFOO_utf8_safe. The function therefore can't check if it is reading beyond the end of the string. Starting in Perl v5.30, it will take a second parameter, becoming a synonym forisFOO_utf8_safe. At that time every program that uses it will have to be changed to successfully compile. In the meantime, the first runtime call toisFOO_utf8 from each call point in the program will raise a deprecation warning, enabled by default. You can convert your program now to useisFOO_utf8_safe, and avoid the warnings, and get an extra measure of protection, or you can wait until v5.30, when you'll be forced to add thee parameter.
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_safe is likeisFOO_LC_uvchr, but is used for UTF-8 encoded strings. Each call classifies one character, even if the string contains many. This variant takes two parameters. The first,p, is a pointer to the first byte of the character to be classified. (Recall that it may take more than one byte to represent a character in UTF-8 strings.) The second parameter,e, points to anywhere in the string beyond the first character, up to one byte past the end of the entire string. The suffix_safe in the function's name indicates that it will not attempt to read beyonde - 1, provided that the constraints < e is true (this is asserted for in-DDEBUGGING builds). If the UTF-8 for the input character is malformed in some way, the program may croak, or the function may return FALSE, at the discretion of the implementation, and subject to change in future releases.
VariantisFOO_LC_utf8 is likeisFOO_LC_utf8_safe, but takes just a single parameter,p, which has the same meaning as the corresponding parameter does inisFOO_LC_utf8_safe. The function therefore can't check if it is reading beyond the end of the string. Starting in Perl v5.30, it will take a second parameter, becoming a synonym forisFOO_LC_utf8_safe. At that time every program that uses it will have to be changed to successfully compile. In the meantime, the first runtime call toisFOO_LC_utf8 from each call point in the program will raise a deprecation warning, enabled by default. You can convert your program now to useisFOO_LC_utf8_safe, and avoid the warnings, and get an extra measure of protection, or you can wait until v5.30, when you'll be forced to add thee parameter.
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_safe,isALPHA_LC,isALPHA_LC_uvchr, andisALPHA_LC_utf8_safe.
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_safe,isALPHANUMERIC_LC,isALPHANUMERIC_LC_uvchr, andisALPHANUMERIC_LC_utf8_safe.
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_safe,isASCII_LC,isASCII_LC_uvchr, andisASCII_LC_utf8_safe. 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_safe 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_safe,isBLANK_LC,isBLANK_LC_uvchr, andisBLANK_LC_utf8_safe. 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_safe,isCNTRL_LC,isCNTRL_LC_uvchr, andisCNTRL_LC_utf8_safe 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_safe,isDIGIT_LC,isDIGIT_LC_uvchr, andisDIGIT_LC_utf8_safe.
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_safe,isGRAPH_LC,isGRAPH_LC_uvchr, andisGRAPH_LC_utf8_safe.
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_safe,isIDCONT_LC,isIDCONT_LC_uvchr, andisIDCONT_LC_utf8_safe.
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_safe,isIDFIRST_LC,isIDFIRST_LC_uvchr, andisIDFIRST_LC_utf8_safe.
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_safe,isLOWER_LC,isLOWER_LC_uvchr, andisLOWER_LC_utf8_safe.
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_safe,isPRINT_LC,isPRINT_LC_uvchr, andisPRINT_LC_utf8_safe.
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_safe,isPSXSPC_LC,isPSXSPC_LC_uvchr, andisPSXSPC_LC_utf8_safe.
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_safe,isPUNCT_LC,isPUNCT_LC_uvchr, andisPUNCT_LC_utf8_safe.
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_safe,isSPACE_LC,isSPACE_LC_uvchr, andisSPACE_LC_utf8_safe.
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_safe,isUPPER_LC,isUPPER_LC_uvchr, andisUPPER_LC_utf8_safe.
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_safe.isWORDCHAR_LC,isWORDCHAR_LC_uvchr, andisWORDCHAR_LC_utf8_safe 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_safe,isXDIGIT_LC,isXDIGIT_LC_uvchr, andisXDIGIT_LC_utf8_safe.
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 a literal string instead of a string/length pair, and no precomputed hash.
COPHH *cophh_delete_pvs(const COPHH *cophh, "literal string" 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 a literal string instead of a string/length pair, and no precomputed hash.
SV *cophh_fetch_pvs(const COPHH *cophh, "literal string" 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 a literal string instead of a string/length pair, and no precomputed hash.
COPHH *cophh_store_pvs(const COPHH *cophh, "literal string" 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 a literal string instead of a string/length pair, and no precomputed hash.
SV *cop_hints_fetch_pvs(const COP *cop, "literal string" 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.
I32axVariable which is setup byxsubpp to indicate the class name for a C++ XS constructor. This is always achar*. See"THIS".
char*CLASSSets 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.
I32itemsVariable which is setup byxsubpp to indicate which of an XSUB's aliases was used to invoke it. See"The ALIAS: Keyword" in perlxs.
I32ixVariable 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)RETVALUsed 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)THISThe 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)Given an op, determine what type of struct it has been allocated as. Returns one of the OPclass enums, such as OPclass_LISTOP.
OPclassop_class(const OP *o)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 return 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 ofname. Note that the actual module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". ver, if specified and not NULL, provides version semantics similar touse Foo::Bar VERSION. The optional trailing arguments can be used to specify arguments to the module'simport() method, similar touse Foo::Bar VERSION LIST; their precise handling depends on the flags. The flags argument is a bitwise-ORed collection of any ofPERL_LOADMOD_DENY,PERL_LOADMOD_NOIMPORT, orPERL_LOADMOD_IMPORT_OPS (or 0 for no flags).
IfPERL_LOADMOD_NOIMPORT is set, the module is loaded as if with an empty import list, as inuse Foo::Bar (); this is the only circumstance in which the trailing optional arguments may be omitted entirely. Otherwise, ifPERL_LOADMOD_IMPORT_OPS is set, the trailing arguments must consist of exactly oneOP*, containing the op tree that produces the relevant import arguments. Otherwise, the trailing arguments must all beSV* values that will be used as import arguments; and the list must be terminated with(SV*) NULL. If neitherPERL_LOADMOD_NOIMPORT norPERL_LOADMOD_IMPORT_OPS is set, the trailingNULL pointer is needed even if no import arguments are desired. The reference count for each specifiedSV* argument is decremented. In addition, thename argument is modified.
IfPERL_LOADMOD_DENY is set, the module is loaded as if withno rather thanuse.
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 levelsSVf_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 for a tutorial.
my_perl points to the Perl interpreter. It must have been previously created through the use of"perl_alloc" and"perl_construct". It may have been initialised through"perl_parse", and may have been used through"perl_run" and other means. This function should be called for any Perl interpreter that has been constructed with"perl_construct", even if subsequent operations on it failed, for example if"perl_parse" returned a non-zero value.
If the interpreter'sPL_exit_flags word has thePERL_EXIT_DESTRUCT_END flag set, then this function will execute code inEND blocks before performing the rest of destruction. If it is desired to make any use of the interpreter between"perl_parse" and"perl_destruct" other than just calling"perl_run", then this flag should be set early on. This matters if"perl_run" will not be called, or if anything else will be done in addition to calling"perl_run".
Returns a value be a suitable value to pass to the C library functionexit (or to return frommain), to serve as an exit code indicating the nature of the way the interpreter terminated. This takes into account any failure of"perl_parse" and any early exit from"perl_run". The exit code is of the type required by the host operating system, so because of differing exit code conventions it is not portable to interpret specific numeric values as having specific meanings.
intperl_destruct(PerlInterpreter *my_perl)Releases a Perl interpreter. Seeperlembed.
voidperl_free(PerlInterpreter *my_perl)Tells a Perl interpreter to parse a Perl script. This performs most of the initialisation of a Perl interpreter. Seeperlembed for a tutorial.
my_perl points to the Perl interpreter that is to parse the script. It must have been previously created through the use of"perl_alloc" and"perl_construct".xsinit points to a callback function that will be called to set up the ability for this Perl interpreter to load XS extensions, or may be null to perform no such setup.
argc andargv supply a set of command-line arguments to the Perl interpreter, as would normally be passed to themain function of a C program.argv[argc] must be null. These arguments are where the script to parse is specified, either by naming a script file or by providing a script in a-e option. If$0 will be written to in the Perl interpreter, then the argument strings must be in writable memory, and so mustn't just be string constants.
env specifies a set of environment variables that will be used by this Perl interpreter. If non-null, it must point to a null-terminated array of environment strings. If null, the Perl interpreter will use the environment supplied by theenviron global variable.
This function initialises the interpreter, and parses and compiles the script specified by the command-line arguments. This includes executing code inBEGIN,UNITCHECK, andCHECK blocks. It does not executeINIT blocks or the main program.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether there was a failure in initialisation. If zero is returned, this indicates that initialisation was successful, and it is safe to proceed to call"perl_run" and make other use of it. If a non-zero value is returned, this indicates some problem that means the interpreter wants to terminate. The interpreter should not be just abandoned upon such failure; the caller should proceed to shut the interpreter down cleanly with"perl_destruct" and free it with"perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library functionexit (or to return frommain), to serve as an exit code indicating the nature of the way initialisation terminated. However, this isn't portable, due to differing exit code conventions. A historical bug is preserved for the time being: if the Perl built-inexit is called during this function's execution, with a type of exit entailing a zero exit code under the host operating system's conventions, then this function returns zero rather than a non-zero value. This bug, [perl #2754], leads toperl_run being called (and thereforeINIT blocks and the main program running) despite a call toexit. It has been preserved because a popular module-installing module has come to rely on it and needs time to be fixed. This issue is [perl #132577], and the original bug is due to be fixed in Perl 5.30.
intperl_parse(PerlInterpreter *my_perl, XSINIT_t xsinit, int argc, char **argv, char **env)Tells a Perl interpreter to run its main program. Seeperlembed for a tutorial.
my_perl points to the Perl interpreter. It must have been previously created through the use of"perl_alloc" and"perl_construct", and initialised through"perl_parse". This function should not be called if"perl_parse" returned a non-zero value, indicating a failure in initialisation or compilation.
This function executes code inINIT blocks, and then executes the main program. The code to be executed is that established by the prior call to"perl_parse". If the interpreter'sPL_exit_flags word does not have thePERL_EXIT_DESTRUCT_END flag set, then this function will also execute code inEND blocks. If it is desired to make any further use of the interpreter after calling this function, thenEND blocks should be postponed to"perl_destruct" time by setting that flag.
Returns an integer of slightly tricky interpretation. The correct use of the return value is as a truth value indicating whether the program terminated non-locally. If zero is returned, this indicates that the program ran to completion, and it is safe to make other use of the interpreter (provided that thePERL_EXIT_DESTRUCT_END flag was set as described above). If a non-zero value is returned, this indicates that the interpreter wants to terminate early. The interpreter should not be just abandoned because of this desire to terminate; the caller should proceed to shut the interpreter down cleanly with"perl_destruct" and free it with"perl_free".
For historical reasons, the non-zero return value also attempts to be a suitable value to pass to the C library functionexit (or to return frommain), to serve as an exit code indicating the nature of the way the program terminated. However, this isn't portable, due to differing exit code conventions. An attempt is made to return an exit code of the type required by the host operating system, but because it is constrained to be non-zero, it is not necessarily possible to indicate every type of exit. It is only reliable on Unix, where a zero exit code can be augmented with a set bit that will be ignored. In any case, this function is not the correct place to acquire an exit code: one should get that from"perl_destruct".
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.
In-place sort an array of SV pointers with the given comparison routine, with various SORTf_* flag options.
voidsortsv_flags(SV** array, size_t num_elts, SVCOMPARE_t cmp, U32 flags)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):
The SV is an HV or a reference to an HV
The hash contains a "version" key
The "version" key has a reference to an AV as its value
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.
U32GIMMEThe 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_VIndicates 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.
For thread safety, modules should not set this variable directly. Instead, use the function"wrap_keyword_plugin".
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_ADDMGThe 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 a literal string instead of a string/length pair.
HV*gv_stashpvs("literal string" 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)NOTE: this function is experimental and may change or be removed without notice.
If the hash is tied dispatches through to the SCALAR tied method, otherwise if the hash contains no keys returns 0, otherwise returns a mortal sv containing a string specifying the number of used buckets, followed by a slash, followed by the number of available buckets.
This function is expensive, it must scan all of the buckets to determine which are used, and the count is NOT cached. In a large hash this could be a lot of buckets.
SV*hv_bucket_ratio(HV *hv)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 a literal string instead of a string/length pair.
SV**hv_fetchs(HV* tb, "literal string" 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.
As of perl 5.25 this function is used only for debugging purposes, and the number of used hash buckets is not in any way cached, thus this function can be costly to execute as it must iterate over all the buckets in the hash.
STRLENhv_fill(HV *const hv)Prepares a starting point to traverse a hash table. Returns the number of keys in the hash, including placeholders (i.e. the same asHvTOTALKEYS(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.
When the hash is tied dispatches through to the SCALAR method, otherwise returns a mortal SV containing the number of keys in the hash.
Note, prior to 5.25 this function returned what is now returned by the hv_bucket_ratio() function.
SV*hv_scalar(HV *hv)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 a literal string instead of a string/length pair and omits the hash parameter.
SV**hv_stores(HV* tb, "literal string" key, 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_checker is written into the"PL_check" array, while the value previously stored there is written to*old_checker_p.
"PL_check" is global to an entire process, and a module wishing to hook op checking may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location*old_checker_p must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also 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.
Taken all together, XS code to hook an op checker should typically look something like this:
static Perl_check_t nxck_frob; static OP *myck_frob(pTHX_ OP *op) {...op = nxck_frob(aTHX_ op);...return op; } BOOT:wrap_op_checker(OP_FROB, myck_frob, &nxck_frob);If you want to influence compilation of calls to a specific subroutine, then use"cv_set_call_checker_flags" rather than hooking checking of 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 a literal string instead of a string/length pair.
voidlex_stuff_pvs("literal string" 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.
NOTE: this function is experimental and may change or be removed without notice.
Puts a C function into the chain of keyword plugins. This is the preferred way to manipulate the"PL_keyword_plugin" variable.new_plugin is a pointer to the C function that is to be added to the keyword plugin chain, andold_plugin_p points to the storage location where a pointer to the next function in the chain will be stored. The value ofnew_plugin is written into the"PL_keyword_plugin" variable, while the value previously stored there is written to*old_plugin_p.
"PL_keyword_plugin" is global to an entire process, and a module wishing to hook keyword parsing may find itself invoked more than once per process, typically in different threads. To handle that situation, this function is idempotent. The location*old_plugin_p must initially (once per process) contain a null pointer. A C variable of static duration (declared at file scope, typically also 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 plugin chain if it finds*old_plugin_p to be null. This function is also thread safe on the small scale. It uses appropriate locking to avoid race conditions in accessing"PL_keyword_plugin".
When this function is called, the function referenced bynew_plugin must be ready to be called, except for*old_plugin_p being unfilled. In a threading situation,new_plugin may be called immediately, even before this function has returned.*old_plugin_p will always be appropriately set beforenew_plugin is called. Ifnew_plugin decides not to do anything special with the identifier that it is given (which is the usual case for most calls to a keyword plugin), it must chain the plugin function referenced by*old_plugin_p.
Taken all together, XS code to install a keyword plugin should typically look something like this:
static Perl_keyword_plugin_t next_keyword_plugin;static OP *my_keyword_plugin(pTHX_ char *keyword_plugin, STRLEN keyword_len, OP **op_ptr){ if (memEQs(keyword_ptr, keyword_len, "my_new_keyword")) { ... } else { return next_keyword_plugin(aTHX_ keyword_ptr, keyword_len, op_ptr); }}BOOT: wrap_keyword_plugin(my_keyword_plugin, &next_keyword_plugin);Direct access to"PL_keyword_plugin" should be avoided.
voidwrap_keyword_plugin( Perl_keyword_plugin_t new_plugin, Perl_keyword_plugin_t *old_plugin_p)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_MANIPULATIONThis is an (almost) drop-in replacement for the systemnl_langinfo(3), taking the sameitem parameter values, and returning the same information. But it is more thread-safe than regularnl_langinfo(), and hides the quirks of Perl's locale handling from your code, and can be used on systems that lack a nativenl_langinfo.
Expanding on these:
The reason it isn't quite a drop-in replacement is actually an advantage. The only difference is that it returnsconst char *, whereas plainnl_langinfo() returnschar *, but you are (only by documentation) forbidden to write into the buffer. By declaring thisconst, the compiler enforces this restriction, so if it is violated, you know at compilation time, rather than getting segfaults at runtime.
It delivers the correct results for theRADIXCHAR andTHOUSEP items, without you having to write extra code. The reason for the extra code would be because these are from theLC_NUMERIC locale category, which is normally kept set by Perl so that the radix is a dot, and the separator is the empty string, no matter what the underlying locale is supposed to be, and so to get the expected results, you have to temporarily toggle into the underlying locale, and later toggle back. (You could use plainnl_langinfo and"STORE_LC_NUMERIC_FORCE_TO_UNDERLYING" for this but then you wouldn't get the other advantages ofPerl_langinfo(); not keepingLC_NUMERIC in the C (or equivalent) locale would break a lot of CPAN, which is expecting the radix (decimal point) character to be a dot.)
The system function it replaces can have its static return buffer trashed, not only by a subesequent call to that function, but by afreelocale,setlocale, or other locale change. The returned buffer of this function is not changed until the next call to it, so the buffer is never in a trashed state.
Its return buffer is per-thread, so it also is never overwritten by a call to this function from another thread; unlike the function it replaces.
But most importantly, it works on systems that don't havenl_langinfo, such as Windows, hence makes your code more portable. Of the fifty-some possible items specified by the POSIX 2008 standard,http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html, only one is completely unimplemented, though on non-Windows platforms, another significant one is also not implemented). It uses various techniques to recover the other items, including callinglocaleconv(3), andstrftime(3), both of which are specified in C89, so should be always be available. Laterstrftime() versions have additional capabilities;"" is returned for those not available on your system.
It is important to note that when called with an item that is recovered by usinglocaleconv, the buffer from any previous explicit call tolocaleconv will be overwritten. This means you must save that buffer's contents if you need to access them after a call to this function. (But note that you might not want to be usinglocaleconv() directly anyway, because of issues like the ones listed in the second item of this list (above) forRADIXCHAR andTHOUSEP. You can use the methods given inperlcall to call"localeconv" in POSIX and avoid all the issues, but then you have a hash to unpack).
The details for those items which may deviate from what this emulation returns and what a nativenl_langinfo() would return are specified inI18N::Langinfo.
When usingPerl_langinfo on systems that don't have a nativenl_langinfo(), you must
#include "perl_langinfo.h"before theperl.h#include. You can replace yourlanginfo.h#include with this one. (Doing it this way keeps out the symbols that plainlanginfo.h would try to import into the namespace for code that doesn't need it.)
The original impetus forPerl_langinfo() was so that code that needs to find out the current currency symbol, floating point radix character, or digit grouping separator can use, on all systems, the simpler and more thread-friendlynl_langinfo API instead oflocaleconv(3) which is a pain to make thread-friendly. For other fields returned bylocaleconv, it is better to use the methods given inperlcall to callPOSIX::localeconv(), which is thread-friendly.
const char* Perl_langinfo(const nl_item item)This is an (almost) drop-in replacement for the systemsetlocale(3), taking the same parameters, and returning the same information, except that it returns the correct underlyingLC_NUMERIC locale. Regularsetlocale will instead returnC if the underlying locale has a non-dot decimal point character, or a non-empty thousands separator for displaying floating point numbers. This is because perl keeps that locale category such that it has a dot and empty separator, changing the locale briefly during the operations where the underlying one is required.Perl_setlocale knows about this, and compensates; regularsetlocale doesn't.
Another reason it isn't completely a drop-in replacement is that it is declared to returnconst char *, whereas the system setlocale omits theconst (presumably because its API was specified long ago, and can't be updated; it is illegal to change the informationsetlocale returns; doing so leads to segfaults.)
Finally,Perl_setlocale works under all circumstances, whereas plainsetlocale can be completely ineffective on some platforms under some configurations.
Perl_setlocale should not be used to change the locale except on systems where the predefined variable${^SAFE_LOCALES} is 1. On some such systems, the systemsetlocale() is ineffective, returning the wrong information, and failing to actually change the locale.Perl_setlocale, however works properly in all circumstances.
The return points to a per-thread static buffer, which is overwritten the next timePerl_setlocale is called from the same thread.
const char* Perl_setlocale(const int category, const char* locale)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.
On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called.
voidSTORE_LC_NUMERIC_FORCE_TO_UNDERLYING()This is used to help wrap XS or C code that isLC_NUMERIC locale-aware. This locale category is generally kept set to a locale where the decimal radix character is a dot, and the separator between groups of digits is empty. This is because most XS code that reads floating point numbers is expecting them to have this syntax.
This macro makes sure the 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(); ...}On threaded perls not operating with thread-safe functionality, this macro uses a mutex to force a critical section. Therefore the matching RESTORE should be close by, and guaranteed to be called.
voidSTORE_LC_NUMERIC_SET_TO_NEEDED()On systems without locale support, or on single-threaded builds, or on platforms that do not support per-thread locale operations, this function does nothing. On such systems that do have locale support, only a locale global to the whole program is available.
On multi-threaded builds on systems that do have per-thread locale operations, this function converts the thread it is running in to use the global locale. This is for code that has not yet or cannot be updated to handle multi-threaded locale operation. As long as only a single thread is so-converted, everything works fine, as all the other threads continue to ignore the global one, so only this thread looks at it.
However, on Windows systems this isn't quite true prior to Visual Studio 15, at which point Microsoft fixed a bug. A race can occur if you use the following operations on earlier Windows platforms:
CRNCYSTR andTHOUSEPCRNCYSTR andTHOUSEPThe first item is not fixable (except by upgrading to a later Visual Studio release), but it would be possible to work around the latter two items by using the Windows API functionsGetNumberFormat andGetCurrencyFormat; patches welcome.
Without this function call, threads that use thesetlocale(3) system function will not work properly, as all the locale-sensitive functions will look at the per-thread locale, andsetlocale will have no effect on this thread.
Perl code should convert to either callPerl_setlocale (which is a drop-in for the systemsetlocale) or use the methods given inperlcall to callPOSIX::setlocale. Either one will transparently properly handle all cases of single- vs multi-thread, POSIX 2008-supported or not.
Non-Perl libraries, such asgtk, that call the systemsetlocale can continue to work if this function is called before transferring control to the library.
Upon return from the code that needs to use the global locale,sync_locale() should be called to restore the safe multi-thread operation.
voidswitch_to_global_locale()Perl_setlocale can be used at any time to query or change the locale (though changing the locale is antisocial and dangerous on multi-threaded systems that don't have multi-thread safe locale operations. (See"Multi-threaded operation" in perllocale). Using the systemsetlocale(3) should be avoided. Nevertheless, certain non-Perl libraries called from XS, such asGtk do so, and this can't be changed. When the locale is changed by XS code that didn't usePerl_setlocale, Perl needs to be told that the locale has changed. Use this function to do so, before returning to Perl.
The return value is a boolean: TRUE if the global locale at the time of call was in effect; and FALSE if a per-thread locale was in effect. This can be used by the caller that needs to restore things as-they-were to decide whether or not to callPerl_switch_to_global_locale.
boolsync_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 using virtual tablevtbl from the SVsv. See"sv_magic".
mg_freeext(sv, how, NULL) is equivalent tomg_free_type(sv, how).
voidmg_freeext(SV* sv, int how, const MGVTBL *vtbl)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$| or a tied variable (it callsSTORE). This macro evaluates its argument more than once.
voidSvSETMAGIC(SV* sv)LikeSvSetSV, but does any set magic required afterwards.
voidSvSetMagicSV(SV* dsv, SV* ssv)LikeSvSetSV_nosteal, but does any set magic required afterwards.
voidSvSetMagicSV_nosteal(SV* dsv, SV* ssv)Callssv_setsv ifdsv is not the same asssv. May evaluate arguments more than once. Does not handle 'set' magic on the destination SV.
voidSvSetSV(SV* dsv, SV* ssv)Calls a non-destructive version ofsv_setsv ifdsv is not the same asssv. May evaluate arguments more than once.
voidSvSetSV_nosteal(SV* dsv, SV* ssv)Arranges forsv to be shared between threads if a suitable module has been loaded.
voidSvSHARE(SV* sv)Generates the message string describing an OS error and returns it as an SV.errnum must be a value thaterrno could take, identifying the type of error.
Iftgtsv is non-null then the string will be written into that SV (overwriting existing content) and it will be returned. Iftgtsv is a null pointer then the string will be written into a new mortal SV which will be returned.
The message will be taken from whatever locale would be used by$!, and will be encoded in the SV in whatever manner would be used by$!. The details of this process are subject to future change. Currently, the message is taken from the C locale by default (usually producing an English message), and from the currently selected locale when in the scope of theuse locale pragma. A heuristic attempt is made to decode the message from the locale's character encoding, but it will only be decoded as either UTF-8 or ISO-8859-1. It is always correctly decoded in a UTF-8 locale, usually in an ISO-8859-1 locale, and never in any other locale.
The SV is always returned containing an actual string, and with no other OK bits set. Unlike$!, a message is even yielded forerrnum zero (meaning success), and if no useful message is available then a useless string (currently empty) is returned.
SV *sv_string_from_errnum(int errnum, SV *tgtsv)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 a literal string instead of a string/length pair.
char*savepvs("literal string" 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("literal string" 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)Analyzes 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 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.
The return value is the total length thatdst would have ifsize is sufficiently large. Thus it is the initial length ofdst plus the length ofsrc. Ifsize is smaller than the return, the excess was not appended.
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.
The return value is the total lengthsrc would be if the copy completely succeeded. If it is larger thansize, the excess was not copied.
Size_tmy_strlcpy(char *dst, const char *src, Size_t size)The C librarystrnlen if available, or a Perl implementation of it.
my_strnlen() computes the length of the string, up tomaxlen characters. It will will never attempt to address more thanmaxlen characters, making it suitable for use with strings that are not guaranteed to be NUL-terminated.
Size_tmy_strnlen(const char *str, Size_t maxlen)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_INFINITYIS_NUMBER_NANIS_NUMBER_INFINITY | IS_NUMBER_NEGIS_NUMBER_NAN | IS_NUMBER_NEG0possibly |-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-#definesignbit 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.
SSize_tunpack_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 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 to whose value$_ will be locally aliased, 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. Depending on the op type, the memory referenced bypv may be freed when the op is destroyed. If the op is of a freeing type,pv must have been allocated usingPerlMemShared_malloc.
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)The original form of"cv_get_call_checker_flags", which does not return checker flags. When using a checker function returned by this function, it is only safe to call it with a genuine GV as itsnamegv argument.
voidcv_get_call_checker(CV *cv, Perl_call_checker *ckfun_p, SV **ckobj_p)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, an SV argument for it is returned in*ckobj_p, and control flags are returned in*ckflags_p. The function is intended to be called in this manner:
entersubop = (*ckfun_p)(aTHX_ entersubop, namegv, (*ckobj_p));In this call,entersubop is a pointer to 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. If theCALL_CHECKER_REQUIRE_GV bit is clear in*ckflags_p, it is permitted to pass a CV or other SV instead, anything that can be used as the first argument to"cv_name". If theCALL_CHECKER_REQUIRE_GV bit is set in*ckflags_p then the check function requiresnamegv to be a genuine GV.
By default, the check function isPerl_ck_entersub_args_proto_or_list, the SV parameter iscv itself, and theCALL_CHECKER_REQUIRE_GV flag is clear. This implements standard prototype processing. It can be changed, for a particular subroutine, by"cv_set_call_checker_flags".
If theCALL_CHECKER_REQUIRE_GV bit is set ingflags then it indicates that the caller only knows about the genuine GV version ofnamegv, and accordingly the corresponding bit will always be set in*ckflags_p, regardless of the check function's recorded requirements. If theCALL_CHECKER_REQUIRE_GV bit is clear ingflags then it indicates the caller knows about the possibility of passing something other than a GV asnamegv, and accordingly the corresponding bit may be either set or clear in*ckflags_p, indicating the check function's recorded requirements.
gflags is a bitset passed intocv_get_call_checker_flags, in which only theCALL_CHECKER_REQUIRE_GV bit currently has a defined meaning (for which see above). All other bits should be clear.
voidcv_get_call_checker_flags( CV *cv, U32 gflags, Perl_call_checker *ckfun_p, SV **ckobj_p, U32 *ckflags_p)The original form of"cv_set_call_checker_flags", which passes it theCALL_CHECKER_REQUIRE_GV flag for backward-compatibility. The effect of that flag setting is that the check function is guaranteed to get a genuine GV as itsnamegv argument.
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, an SV argument for it is supplied inckobj, and control flags are supplied inckflags. 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 theckflags.
ckflags is a bitset, in which only theCALL_CHECKER_REQUIRE_GV bit currently has a defined meaning (for which see above). All other bits should be clear.
The current setting for a particular CV can be retrieved by"cv_get_call_checker_flags".
voidcv_set_call_checker_flags( CV *cv, Perl_call_checker ckfun, SV *ckobj, U32 ckflags)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)Behaves like"newCONSTSUB_flags", except thatname is nul-terminated rather than of counted length, and no flags are set. (This means thatname is always interpreted as Latin-1.)
CV *newCONSTSUB(HV *stash, const char *name, SV *sv)Construct a constant subroutine, also performing some surrounding jobs. A scalar constant-valued subroutine is eligible for inlining at compile-time, and in Perl code can be created bysub FOO () { 123 }. Other kinds of constant subroutine have other treatment.
The subroutine will have an empty prototype and will ignore any arguments when called. Its constant behaviour is determined bysv. Ifsv is null, the subroutine will yield an empty list. Ifsv points to a scalar, the subroutine will always yield that scalar. Ifsv points to an array, the subroutine will always yield a list of the elements of that array in list context, or the number of elements in the array in scalar context. This function takes ownership of one counted reference to the scalar or array, and will arrange for the object to live as long as the subroutine does. Ifsv points to a scalar then the inlining assumes that the value of the scalar will never change, so the caller must ensure that the scalar is not subsequently written to. Ifsv points to an array then no such assumption is made, so it is ostensibly safe to mutate the array or its elements, but whether this is really supported has not been determined.
The subroutine will haveCvFILE set according toPL_curcop. Other aspects of the subroutine will be left in their default state. The caller is free to mutate the subroutine beyond its initial state after this function has returned.
Ifname is null then the subroutine will be anonymous, with itsCvGV referring to an__ANON__ glob. Ifname is non-null then the subroutine will be named accordingly, referenced by the appropriate glob.name is a string of lengthlen bytes giving a sigilless symbol name, in UTF-8 ifflags has theSVf_UTF8 bit set and in Latin-1 otherwise. The name may be either qualified or unqualified. If the name is unqualified then it defaults to being in the stash specified bystash if that is non-null, or toPL_curstash ifstash is null. The symbol is always added to the stash if necessary, withGV_ADDMULTI semantics.
flags should not have bits set other thanSVf_UTF8.
If there is already a subroutine of the specified name, then the new sub will replace the existing one in the glob. A warning may be generated about the redefinition.
If the subroutine has one of a few special names, such asBEGIN orEND, then it will be claimed by the appropriate queue for automatic running of phase-related subroutines. In this case the relevant glob will be left not containing any subroutine, even if it did contain one before. Execution of the subroutine will likely be a no-op, unlesssv was a tied array or the caller modified the subroutine in some interesting way before it was executed. In the case ofBEGIN, the treatment is buggy: the sub will be executed when only half built, and may be deleted prematurely, possibly causing a crash.
The function returns a pointer to the constructed subroutine. If the sub is anonymous then ownership of one counted reference to the subroutine is transferred to the caller. If the sub is named then the caller does not get ownership of a reference. In most such cases, where the sub has a non-phase name, the sub will be alive at the point it is returned by virtue of being contained in the glob that names it. A phase-named subroutine will usually be alive by virtue of the reference owned by the phase's automatic run queue. ABEGIN subroutine may have been destroyed already by the time this function returns, but currently bugs occur in that case before the caller gets control. It is the caller's responsibility to ensure that it knows which of these situations applies.
CV *newCONSTSUB_flags(HV *stash, const char *name, STRLEN len, U32 flags, SV *sv)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; in v5.26 onwards, see also the function"op_class" which can do a better job of determining the used type.
For custom ops the type is returned from the registration, and it is up to the registree to ensure it is accurate. The value returned will be one of 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-DFor 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).
SSize_tunpackstring(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); .... }When a lexical var hasn't yet been introduced, it already exists from the perspective of duplicate declarations, but not for variable lookups, e.g.
my ($x, $x); # '"my" variable $x masks earlier declaration'my $x = $x; # equal to my $x = $::x;For typed 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 a literal string instead of a string/length pair.
PADOFFSET pad_add_name_pvs("literal string" 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 a literal string instead of a string/length pair.
PADOFFSET pad_findmy_pvs("literal string" 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 isPadARRAY(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_modglobalA 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_naWhen 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_opfreehookPointer 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_peeppPointer 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_rpeeppThis is thefalse SV. See"PL_sv_yes". Always refer to this as&PL_sv_no.
SVPL_sv_noThis is theundef SV. Always refer to this as&PL_sv_undef.
SVPL_sv_undefThis is thetrue SV. See"PL_sv_no". Always refer to this as&PL_sv_yes.
SVPL_sv_yesThis readonly SV has a zero numeric value and a"0" string value. It's similar to"PL_sv_no" except for its string value. Can be used as a cheap alternative tomXPUSHi(0) for example. Always refer to this as&PL_sv_zero. Introduced in 5.28.
SVPL_sv_zeroConvenience 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.
IVPOPiPops a long off the stack.
longPOPlPops a double off the stack.
NVPOPnPops a string off the stack.
char*POPpPops a string off the stack which must consist of bytes i.e. characters < 256.
char*POPpbytexPops a string off the stack. Identical to POPp. There are two names for historical reasons.
char*POPpxPops an SV off the stack.
SV*POPsPops an unsigned integer off the stack.
UVPOPuPops an unsigned long off the stack.
longPOPulPush 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).
This function can cause reliability issues if you are likely to pass in empty strings that are not null terminated, because it will run strlen on the string and potentially run past valid memory.
Using"newSVpvn" is a safer alternative for nonNUL terminated strings. For string literals use"newSVpvs" instead. This function will work fine forNUL terminated strings, but if you want to avoid the if statement on whether to callstrlen usenewSVpvn instead (callingstrlen yourself).
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 thes argument is NULL the new SV will be undefined.
SV*newSVpvn(const char *const buffer, 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 a literal string instead of a string/length pair.
SV*newSVpvs("literal string" s)LikenewSVpvn_flags, but takes a literal string instead of a string/length pair.
SV*newSVpvs_flags("literal string" 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 a literal string instead of a string/length pair and omits the hash parameter.
SV*newSVpvs_share("literal string" 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 likesprintf, and appends the formatted output to an SV. As withsv_vcatpvfn 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 a literal string instead of a string/length pair.
voidsv_catpvs(SV* sv, "literal string" s)Likesv_catpvn_flags, but takes a literal string instead of a string/length pair.
voidsv_catpvs_flags(SV* sv, "literal string" s, I32 flags)Likesv_catpvn_mg, but takes a literal string instead of a string/length pair.
voidsv_catpvs_mg(SV* sv, "literal string" s)Likesv_catpvn_nomg, but takes a literal string instead of a string/length pair.
voidsv_catpvs_nomg(SV* sv, "literal string" 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)Copies a stringified representation of the source SV into the destination SV. Automatically performs any necessarymg_get and coercion of numeric values into strings. Guaranteed to preserveUTF8 flag even from overloaded objects. Similar in nature tosv_2pv[_flags] but operates directly on an SV instead of just the string. Mostly usessv_2pv_flags to do its work, except when that would lose the UTF-8'ness of the PV.
voidsv_copypv(SV *const dsv, SV *const ssv)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 *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 asavepvncopy 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)Unweaken a reference: Clear theSvWEAKREF flag on this RV; remove the backreference to this RV from the array of backreferences associated with the target SV, increment the refcount of the target. Silently ignoresundef and warns on non-weak references.
SV*sv_rvunweaken(SV *const sv)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. Silently ignoresundef and warns on already-weak references.
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, and not contain embededNUL's. 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 a literal string instead of a string/length pair.
voidsv_setpvs(SV* sv, "literal string" s)Likesv_setpvn_mg, but takes a literal string instead of a string/length pair.
voidsv_setpvs_mg(SV* sv, "literal string" s)Sets the SV to be a string of cur bytes length, with at least len bytes available. Ensures that there is a null byte at SvEND. Returns a char * pointer to the SvPV buffer.
char *sv_setpv_bufsize(SV *const sv, const STRLEN cur, const STRLEN len)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 a literal string instead of a string/length pair.
SV *sv_setref_pvs("literal string" 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)Equivalent tosv_setsv(sv, &PL_sv_undef), but more efficient. Doesn't handle set magic.
The perl equivalent is$sv = undef;. Note that it doesn't free any string buffer, unlikeundef $sv.
Introduced in perl 5.25.12.
voidsv_set_undef(SV *sv)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 Perl's extended 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.
TheSV_FORCE_UTF8_UPGRADE flag is now ignored.
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_vcatpvfn called with a non-null C-style variable argument list, and appends the formatted output 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 Size_t sv_count, 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.
It assumes that pat has the same utf8-ness as sv. It's the caller's responsibility to ensure that this is so.
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 Size_t sv_count, 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 Size_t sv_count, 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_PVIOThese 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(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.
You might mistakenly think thatlen is the number of bytes to add to the existing size, but instead it is the total sizesv should be.
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 IV and returns it. The returned value in many circumstances will get stored insv's IV slot, but not in all cases. (Use"sv_setiv" to make sure it does).
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 IV and returns it. The returned value in many circumstances will get stored insv's IV slot, but not in all cases. (Use"sv_setiv" to make sure it does).
This form 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)Coerces the given SV to NV and returns it. The returned value in many circumstances will get stored insv's NV slot, but not in all cases. (Use"sv_setnv" to make sure it does).
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 NV and returns it. The returned value in many circumstances will get stored insv's NV slot, but not in all cases. (Use"sv_setnv" to make sure it does).
This form 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(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)Ensures that sv is a SVt_PV and that its SvCUR is 0, and that it is properly null terminated. Equivalent to sv_setpvs(""), but more efficient.
char *SvPVCLEAR(SV* sv)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 true if the argument is readonly, otherwise returns false. Exposed to to perl code via Internals::SvREADONLY().
U32SvREADONLY(SV* sv)Mark an object as not-readonly. Exactly what this mean depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32SvREADONLY_off(SV* sv)Mark an object as readonly. Exactly what this means depends on the object type. Exposed to perl code via Internals::SvREADONLY().
U32SvREADONLY_on(SV* sv)Returns the value of the object's reference count. Exposed to perl code via Internals::SvREFCNT().
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(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 UV and returns it. The returned value in many circumstances will get stored insv's UV slot, but not in all cases. (Use"sv_setuv" to make sure it does).
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 UV and returns it. The returned value in many circumstances will get stored insv's UV slot, but not in all cases. (Use"sv_setuv" to make sure it does).
This form 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.
This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode BYTE ORDER MARK (U+FEFF) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms.sizeof(BOM_UTF8) - 1 can be used to get its length in bytes.
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 potentially UTF-8 encoded strings of length*lenp into native byte encoding. On input, the boolean*is_utf8p gives whether or nots is actually encoded in UTF-8.
Unlike"utf8_to_bytes" but like"bytes_to_utf8", this is non-destructive of the input string.
Do nothing if*is_utf8p is 0, or if there are code points in the string not expressible in native byte encoding. In these cases,*is_utf8p and*lenp are unchanged, and the return value is the originals.
Otherwise,*is_utf8p is set to 0, and the return value is a pointer to a newly created string containing a downgraded copy ofs, and whose length is returned in*lenp, updated. The new string isNUL-terminated. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of*lenp before the call, and subtracting the after-call value of*lenp from it.
U8*bytes_from_utf8(const U8 *s, STRLEN *lenp, bool *is_utf8p)NOTE: this function is experimental and may change or be removed without notice.
Converts a strings of length*lenp bytes from the native encoding into UTF-8. Returns a pointer to the newly-created string, and sets*lenp to reflect the new length in bytes. The caller is responsible for arranging for the memory used by this string to get freed.
Upon successful return, the number of variants in the string can be computed by having saved the value of*lenp before the call, and subtracting it from the after-call value of*lenp.
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 *lenp)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_utf8_invariant_string". On ASCII-ish platforms, the name isn't misleading: the ASCII-range characters are exactly the UTF-8 invariants. But EBCDIC machines have more invariants than just the ASCII characters, sois_utf8_invariant_string is preferred.
boolis_ascii_string(const U8* const s, STRLEN len)Returns TRUE if the firstlen bytes of strings form a valid UTF-8-encoded string that conforms toUnicode Corrigendum #9; otherwise it returns FALSE. 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'.
This function returns FALSE for strings containing any code points above the Unicode max of 0x10FFFF or surrogate code points, but accepts non-character code points perCorrigendum #9.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string","is_utf8_string_flags","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
boolis_c9strict_utf8_string(const U8 *s, STRLEN len)Like"is_c9strict_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 pointer.
See also"is_c9strict_utf8_string_loclen".
boolis_c9strict_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)Like"is_c9strict_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 pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_c9strict_utf8_string_loc".
boolis_c9strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)Evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents some Unicode non-surrogate code point; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF. This differs from"isSTRICT_UTF8_CHAR" only in that it accepts non-character code points. This corresponds toUnicode Corrigendum #9. which said that non-character code points are merely discouraged rather than completely forbidden in open interchange. See"Noncharacter code points" in perlunicode.
Use"isUTF8_CHAR" to check for Perl's extended UTF-8; and"isUTF8_CHAR_flags" for a more customized definition.
Use"is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen" to check entire strings.
STRLENisC9_STRICT_UTF8_CHAR(const U8 *s, const U8 *e)This is a somewhat misleadingly-named synonym for"is_utf8_invariant_string".is_utf8_invariant_string is preferred, as it indicates under what conditions the string is invariant.
boolis_invariant_string(const U8* const s, STRLEN len)Evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents some Unicode code point completely acceptable for open interchange between all applications; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
The largest acceptable code point is the Unicode maximum 0x10FFFF, and must not be a surrogate nor a non-character code point. Thus this excludes any code point from Perl's extended UTF-8.
This is used to efficiently decide if the next few bytes ins is legal Unicode-acceptable UTF-8 for a single character.
Use"isC9_STRICT_UTF8_CHAR" to use theUnicode Corrigendum #9 definition of allowable code points;"isUTF8_CHAR" to check for Perl's extended UTF-8; and"isUTF8_CHAR_flags" for a more customized definition.
Use"is_strict_utf8_string","is_strict_utf8_string_loc", and"is_strict_utf8_string_loclen" to check entire strings.
STRLENisSTRICT_UTF8_CHAR(const U8 *s, const U8 *e)Returns TRUE if the firstlen bytes of strings form a valid UTF-8-encoded string that is fully interchangeable by any application using Unicode rules; otherwise it returns FALSE. 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'.
This function returns FALSE for strings containing any code points above the Unicode max of 0x10FFFF, surrogate code points, or non-character code points.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string","is_utf8_string_flags","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
boolis_strict_utf8_string(const U8 *s, STRLEN len)Like"is_strict_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 pointer.
See also"is_strict_utf8_string_loclen".
boolis_strict_utf8_string_loc(const U8 *s, STRLEN len, const U8 **ep)Like"is_strict_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 pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_strict_utf8_string_loc".
boolis_strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)Returns TRUE if the fixed-width buffer starting ats with lengthlen is entirely valid UTF-8, subject to the restrictions given byflags; otherwise it returns FALSE.
Ifflags is 0, any well-formed UTF-8, as extended by Perl, is accepted without restriction. If the final few bytes of the buffer do not form a complete code point, this will return TRUE anyway, provided that"is_utf8_valid_partial_char_flags" returns TRUE for them.
Ifflags in non-zero, it can be any combination of theUTF8_DISALLOW_foo flags accepted by"utf8n_to_uvchr", and with the same meanings.
This function differs from"is_utf8_string_flags" only in that the latter returns FALSE if the final few bytes of the string don't form a complete code point.
boolis_utf8_fixed_width_buf_flags( const U8 * const s, STRLEN len, const U32 flags)Like"is_utf8_fixed_width_buf_loc_flags" but stores the number of complete, valid characters found in theel pointer.
boolis_utf8_fixed_width_buf_loclen_flags( const U8 * const s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)Like"is_utf8_fixed_width_buf_flags" but stores the location of the failure in theep pointer. If the function returns TRUE,*ep will point to the beginning of any partial character at the end of the buffer; if there is no partial character*ep will contains+len.
See also"is_utf8_fixed_width_buf_loclen_flags".
boolis_utf8_fixed_width_buf_loc_flags( const U8 * const s, STRLEN len, const U8 **ep, const U32 flags)Returns TRUE if 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); otherwise it returns FALSE. That is, it returns TRUE if they are UTF-8 invariant. On ASCII-ish machines, all the ASCII characters and only the ASCII characters fit this definition. On EBCDIC machines, the ASCII-range characters are invariant, but so also are the C1 controls.
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_flags","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
boolis_utf8_invariant_string(const U8* const s, STRLEN len)Like"is_utf8_invariant_string" but upon failure, stores the location of the first UTF-8 variant character in theep pointer; if all characters are UTF-8 invariant, this function does not change the contents of*ep.
boolis_utf8_invariant_string_loc(const U8* const s, STRLEN len, const U8 ** ep)Returns TRUE if the firstlen bytes of strings form a valid Perl-extended-UTF-8 string; returns 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'.
This function considers Perl's extended UTF-8 to be valid. That means that code points above Unicode, surrogates, and non-character code points are considered valid by this function. Use"is_strict_utf8_string","is_c9strict_utf8_string", or"is_utf8_string_flags" to restrict what code points are considered valid.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string_loc","is_utf8_string_loclen","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags",
boolis_utf8_string(const U8 *s, STRLEN len)Returns TRUE if the firstlen bytes of strings form a valid UTF-8 string, subject to the restrictions imposed byflags; returns 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'.
Ifflags is 0, this gives the same results as"is_utf8_string"; ifflags isUTF8_DISALLOW_ILLEGAL_INTERCHANGE, this gives the same results as"is_strict_utf8_string"; and ifflags isUTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE, this gives the same results as"is_c9strict_utf8_string". Otherwiseflags may be any combination of theUTF8_DISALLOW_foo flags understood by"utf8n_to_uvchr", with the same meanings.
See also"is_utf8_invariant_string","is_utf8_invariant_string_loc","is_utf8_string","is_utf8_string_loc","is_utf8_string_loc_flags","is_utf8_string_loclen","is_utf8_string_loclen_flags","is_utf8_fixed_width_buf_flags","is_utf8_fixed_width_buf_loc_flags","is_utf8_fixed_width_buf_loclen_flags","is_strict_utf8_string","is_strict_utf8_string_loc","is_strict_utf8_string_loclen","is_c9strict_utf8_string","is_c9strict_utf8_string_loc", and"is_c9strict_utf8_string_loclen".
boolis_utf8_string_flags(const U8 *s, STRLEN len, const U32 flags)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 pointer.
See also"is_utf8_string_loclen".
boolis_utf8_string_loc(const U8 *s, const 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 pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_utf8_string_loc".
boolis_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)Like"is_utf8_string_flags" 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 pointer, and the number of UTF-8 encoded characters in theel pointer.
See also"is_utf8_string_loc_flags".
boolis_utf8_string_loclen_flags(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)Like"is_utf8_string_flags" 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 pointer.
See also"is_utf8_string_loclen_flags".
boolis_utf8_string_loc_flags(const U8 *s, STRLEN len, const U8 **ep, const U32 flags)Returns 0 if the sequence of bytes starting ats and looking no further thane - 1 is the UTF-8 encoding, as extended by Perl, for one or more code points. Otherwise, it returns 1 if there exists at least one non-empty sequence of bytes that when appended to sequences, starting at positione causes the entire sequence to be the well-formed UTF-8 of some code point; otherwise returns 0.
In other words this returns TRUE ifs points to a partial UTF-8-encoded code point.
This is useful when a fixed-length buffer is being tested for being well-formed UTF-8, but the final few bytes in it don't comprise a full character; that is, it is split somewhere in the middle of the final code point's UTF-8 representation. (Presumably when the buffer is refreshed with the next chunk of data, the new first bytes will complete the partial code point.) This function is used to verify that the final bytes in the current buffer are in fact the legal beginning of some code point, so that if they aren't, the failure can be signalled without having to wait for the next read.
boolis_utf8_valid_partial_char(const U8 * const s, const U8 * const e)Like"is_utf8_valid_partial_char", it returns a boolean giving whether or not the input is a valid UTF-8 encoded partial character, but it takes an extra parameter,flags, which can further restrict which code points are considered valid.
Ifflags is 0, this behaves identically to"is_utf8_valid_partial_char". Otherwiseflags can be any combination of theUTF8_DISALLOW_foo flags accepted by"utf8n_to_uvchr". If there is any sequence of bytes that can complete the input partial character in such a way that a non-prohibited character is formed, the function returns TRUE; otherwise FALSE. Non character code points cannot be determined based on partial character input. But many of the other possible excluded types can be determined from just the first one or two bytes.
boolis_utf8_valid_partial_char_flags( const U8 * const s, const U8 * const e, const U32 flags)Evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8, as extended by Perl, that represents some code point; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
The code point can be any that will fit in a UV on this machine, using Perl's extension to official UTF-8 to represent those higher than the Unicode maximum of 0x10FFFF. That means that this macro is used to efficiently decide if the next few bytes ins is legal UTF-8 for a single character.
Use"isSTRICT_UTF8_CHAR" to restrict the acceptable code points to those defined by Unicode to be fully interchangeable across applications;"isC9_STRICT_UTF8_CHAR" to use theUnicode Corrigendum #9 definition of allowable code points; and"isUTF8_CHAR_flags" for a more customized definition.
Use"is_utf8_string","is_utf8_string_loc", and"is_utf8_string_loclen" to check entire strings.
Note that it is deprecated to use code points higher than what will fit in an IV. This macro does not raise any warnings for such code points, treating them as valid.
Note also that a UTF-8 INVARIANT character (i.e. ASCII on non-EBCDIC machines) is a valid UTF-8 character.
STRLENisUTF8_CHAR(const U8 *s, const U8 *e)Evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8, as extended by Perl, that represents some code point, subject to the restrictions given byflags; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation. Any bytes remaining beforee, but beyond the ones needed to form the first code point ins, are not examined.
Ifflags is 0, this gives the same results as"isUTF8_CHAR"; ifflags isUTF8_DISALLOW_ILLEGAL_INTERCHANGE, this gives the same results as"isSTRICT_UTF8_CHAR"; and ifflags isUTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE, this gives the same results as"isC9_STRICT_UTF8_CHAR". Otherwiseflags may be any combination of theUTF8_DISALLOW_foo flags understood by"utf8n_to_uvchr", with the same meanings.
The three alternative macros are for the most commonly needed validations; they are likely to run somewhat faster than this more general one, as they can be inlined into your code.
Use"is_utf8_string_flags","is_utf8_string_loc_flags", and"is_utf8_string_loclen_flags" to check entire strings.
STRLENisUTF8_CHAR_flags(const U8 *s, const U8 *e, const U32 flags)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)This is a macro that evaluates to a string constant of the UTF-8 bytes that define the Unicode REPLACEMENT CHARACTER (U+FFFD) for the platform that perl is compiled on. This allows code to use a mnemonic for this character that works on both ASCII and EBCDIC platforms.sizeof(REPLACEMENT_CHARACTER_UTF8) - 1 can be used to get its length in bytes.
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"toFOLD_utf8_safe".
UVto_utf8_fold(const U8 *p, U8* ustrp, STRLEN *lenp)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"toLOWER_utf8_safe".
UVto_utf8_lower(const U8 *p, U8* ustrp, STRLEN *lenp)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"toTITLE_utf8_safe".
UVto_utf8_title(const U8 *p, U8* ustrp, STRLEN *lenp)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"toUPPER_utf8_safe".
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, encountering a malformation causes zero to be 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. Some UTF-8 input sequences may contain multiple malformations. This function tries to find every possible one in each call, so multiple warnings can be raised for the same sequence.
Various ALLOW flags can be set 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. Even if allowed, this function generally returns the Unicode REPLACEMENT CHARACTER when it encounters a malformation. There are flags inutf8.h to override this behavior for the overlong malformations, but don't do that except for very specialized purposes.
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, and, depending on the malformation,retlen may be set to 1. 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. Or you can use"utf8n_to_uvchr_error".
Certain code points are considered problematic. These are Unicode surrogates, Unicode non-characters, and code points above the Unicode maximum of 0x10FFFF. By default these are considered regular code points, but certain situations warrant special handling for them, which can be specified using theflags parameter. 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.UTF8_DISALLOW_ILLEGAL_INTERCHANGE restricts the allowed inputs to the strict UTF-8 traditionally defined by Unicode. UseUTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE to use the strictness definition given byUnicode Corrigendum #9. The difference between traditional strictness and C9 strictness is that the latter does not forbid non-character code points. (They are still discouraged, however.) For more discussion see"Noncharacter code points" in perlunicode.
The flagsUTF8_WARN_ILLEGAL_INTERCHANGE,UTF8_WARN_ILLEGAL_C9_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.)
Extremely high code points were never specified in any standard, and require an extension to UTF-8 to express, which Perl does. It is likely that programs written in something other than Perl would not be able to read files that contain these; nor would Perl understand files written by something that uses a different extension. For these reasons, there is a separate set of flags that can warn and/or disallow these extremely high code points, even if other above-Unicode ones are accepted. They are theUTF8_WARN_PERL_EXTENDED andUTF8_DISALLOW_PERL_EXTENDED flags. For more information see"UTF8_GOT_PERL_EXTENDED". Of courseUTF8_DISALLOW_SUPER will treat all above-Unicode code points, including these, as malformations. (Note that the Unicode standard considers anything above 0x10FFFF to be illegal, but there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym forUTF8_WARN_PERL_EXTENDED is retained for backward compatibility:UTF8_WARN_ABOVE_31_BIT. Similarly,UTF8_DISALLOW_ABOVE_31_BIT is usable instead of the more accurately namedUTF8_DISALLOW_PERL_EXTENDED. The names are misleading because these flags can apply to code points that actually do fit in 31 bits. This happens on EBCDIC platforms, and sometimes when theoverlong malformation is also present. The new names accurately describe the situation in all cases.
All other code points corresponding to Unicode characters, including private use and those yet to be assigned, are never considered malformed and never warn.
UVutf8n_to_uvchr(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags)THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use"utf8_to_uvchr_buf"() rather than call this directly.
This function is for code that needs to know what the precise malformation(s) are when an error is found. If you also need to know the generated warning messages, use"utf8n_to_uvchr_msgs"() instead.
It is like"utf8n_to_uvchr" but it takes an extra parameter placed after all the others,errors. If this parameter is 0, this function behaves identically to"utf8n_to_uvchr". Otherwise,errors should be a pointer to aU32 variable, which this function sets to indicate any errors found. Upon return, if*errors is 0, there were no errors found. Otherwise,*errors is the bit-wiseOR of the bits described in the list below. Some of these bits will be set if a malformation is found, even if the inputflags parameter indicates that the given malformation is allowed; those exceptions are noted:
UTF8_GOT_PERL_EXTENDEDThe input sequence is not standard UTF-8, but a Perl extension. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_PERL_EXTENDED or theUTF8_WARN_PERL_EXTENDED flags.
Code points above 0x7FFF_FFFF (2**31 - 1) were never specified in any standard, and so some extension must be used to express them. Perl uses a natural extension to UTF-8 to represent the ones up to 2**36-1, and invented a further extension to represent even higher ones, so that any code point that fits in a 64-bit word can be represented. Text using these extensions is not likely to be portable to non-Perl code. We lump both of these extensions together and refer to them as Perl extended UTF-8. There exist other extensions that people have invented, incompatible with Perl's.
On EBCDIC platforms starting in Perl v5.24, the Perl extension for representing extremely high code points kicks in at 0x3FFF_FFFF (2**30 -1), which is lower than on ASCII. Prior to that, code points 2**31 and higher were simply unrepresentable, and a different, incompatible method was used to represent code points between 2**30 and 2**31 - 1.
On both platforms, ASCII and EBCDIC,UTF8_GOT_PERL_EXTENDED is set if Perl extended UTF-8 is used.
In earlier Perls, this bit was namedUTF8_GOT_ABOVE_31_BIT, which you still may use for backward compatibility. That name is misleading, as this flag may be set when the code point actually does fit in 31 bits. This happens on EBCDIC platforms, and sometimes when theoverlong malformation is also present. The new name accurately describes the situation in all cases.
UTF8_GOT_CONTINUATIONThe input sequence was malformed in that the first byte was a a UTF-8 continuation byte.
UTF8_GOT_EMPTYThe inputcurlen parameter was 0.
UTF8_GOT_LONGThe input sequence was malformed in that there is some other sequence that evaluates to the same code point, but that sequence is shorter than this one.
Until Unicode 3.1, it was legal for programs to accept this malformation, but it was discovered that this created security issues.
UTF8_GOT_NONCHARThe code point represented by the input UTF-8 sequence is for a Unicode non-character code point. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_NONCHAR or theUTF8_WARN_NONCHAR flags.
UTF8_GOT_NON_CONTINUATIONThe input sequence was malformed in that a non-continuation type byte was found in a position where only a continuation type one should be.
UTF8_GOT_OVERFLOWThe input sequence was malformed in that it is for a code point that is not representable in the number of bits available in an IV on the current platform.
UTF8_GOT_SHORTThe input sequence was malformed in thatcurlen is smaller than required for a complete sequence. In other words, the input is for a partial character sequence.
UTF8_GOT_SUPERThe input sequence was malformed in that it is for a non-Unicode code point; that is, one above the legal Unicode maximum. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_SUPER or theUTF8_WARN_SUPER flags.
UTF8_GOT_SURROGATEThe input sequence was malformed in that it is for a -Unicode UTF-16 surrogate code point. This bit is set only if the inputflags parameter contains either theUTF8_DISALLOW_SURROGATE or theUTF8_WARN_SURROGATE flags.
To do your own error handling, call this function with theUTF8_CHECK_ONLY flag to suppress any warnings, and then examine the*errors return.
UVutf8n_to_uvchr_error(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags, U32 * errors)NOTE: this function is experimental and may change or be removed without notice.
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES. Most code should use"utf8_to_uvchr_buf"() rather than call this directly.
This function is for code that needs to know what the precise malformation(s) are when an error is found, and wants the corresponding warning and/or error messages to be returned to the caller rather than be displayed. All messages that would have been displayed if all lexcial warnings are enabled will be returned.
It is just like"utf8n_to_uvchr_error" but it takes an extra parameter placed after all the others,msgs. If this parameter is 0, this function behaves identically to"utf8n_to_uvchr_error". Otherwise,msgs should be a pointer to anAV * variable, in which this function creates a new AV to contain any appropriate messages. The elements of the array are ordered so that the first message that would have been displayed is in the 0th element, and so on. Each element is a hash with three key-value pairs, as follows:
textThe text of the message as aSVpv.
warn_categoriesThe warning category (or categories) packed into aSVuv.
flagA single flag bit associated with this message, in aSVuv. The bit corresponds to some bit in the*errors return value, such asUTF8_GOT_LONG.
It's important to note that specifying this parameter as non-null will cause any warnings this function would otherwise generate to be suppressed, and instead be placed in*msgs. The caller can check the lexical warnings state (or not) when choosing what to do with the returned messages.
If the flagUTF8_CHECK_ONLY is passed, no warnings are generated, and hence no AV is created.
The caller, of course, is responsible for freeing any returned AV.
UVutf8n_to_uvchr_msgs(const U8 *s, STRLEN curlen, STRLEN *retlen, const U32 flags, U32 * errors, AV ** msgs)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 UTF-8 pointers displaced by up tooff characters, backward.
off must be non-positive.
s must be after or equal tostart.
When moving backward it will not move beforestart.
Will not exceed this limit even if the string is not valid "UTF-8".
U8*utf8_hop_back(const U8 *s, SSize_t off, const U8 *start)Return the UTF-8 pointers displaced by up tooff characters, forward.
off must be non-negative.
s must be before or equal toend.
When moving forward it will not move beyondend.
Will not exceed this limit even if the string is not valid "UTF-8".
U8*utf8_hop_forward(const U8 *s, SSize_t off, const U8 *end)Return the UTF-8 pointers displaced by up tooff characters, either forward or backward.
When moving backward it will not move beforestart.
When moving forward it will not move beyondend.
Will not exceed those limits even if the string is not valid "UTF-8".
U8*utf8_hop_safe(const U8 *s, SSize_t off, const U8 *start, const U8 *end)Evaluates to 1 if the bytec represents the same character when encoded in UTF-8 as when not; otherwise evaluates to 0. UTF-8 invariant characters can be copied as-is when converting to/from UTF-8, saving time.
In spite of the name, this macro gives the correct result if the input string from whichc comes is not encoded in UTF-8.
See"UVCHR_IS_INVARIANT" for checking if a UV is invariant.
boolUTF8_IS_INVARIANT(char c)Evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents one of the Unicode non-character code points; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation.
boolUTF8_IS_NONCHAR(const U8 *s, const U8 *e)Recall that Perl recognizes an extension to UTF-8 that can encode code points larger than the ones defined by Unicode, which are 0..0x10FFFF.
This macro evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are from this UTF-8 extension; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation.
0 is returned if the bytes are not well-formed extended UTF-8, or if they represent a code point that cannot fit in a UV on the current platform. Hence this macro can give different results when run on a 64-bit word machine than on one with a 32-bit word size.
Note that it is deprecated to have code points that are larger than what can fit in an IV on the current machine.
boolUTF8_IS_SUPER(const U8 *s, const U8 *e)Evaluates to non-zero if the first few bytes of the string starting ats and looking no further thane - 1 are well-formed UTF-8 that represents one of the Unicode surrogate code points; otherwise it evaluates to 0. If non-zero, the value gives how many bytes starting ats comprise the code point's representation.
boolUTF8_IS_SURROGATE(const U8 *s, const U8 *e)Returns the number of characters in the sequence of UTF-8-encoded bytes starting ats and ending at the byte just beforee. If <s> and <e> point to the same place, it returns 0 with no warning raised.
Ife < s or if the scan would end up paste, it raises a UTF8 warning and returns the number of valid characters.
STRLENutf8_length(const U8* s, const U8 *e)NOTE: this function is experimental and may change or be removed without notice.
Converts a string"s" of length*lenp from UTF-8 into native byte encoding. Unlike"bytes_to_utf8", this over-writes the original string, and updates*lenp to contain the new length. Returns zero on failure (leaving"s" unchanged) setting*lenp to -1.
Upon successful return, the number of variants in the string can be computed by having saved the value of*lenp before the call, and subtracting the after-call value of*lenp from it.
If you need a copy of the string, see"bytes_from_utf8".
U8*utf8_to_bytes(U8 *s, STRLEN *lenp)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)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.
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. If you are not absolutely sure this is one of those cases, then assume it isn't and use plainutf8_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.
UVutf8_to_uvuni_buf(const U8 *s, const U8 *send, STRLEN *retlen)Evaluates to 1 if the representation of code pointcp is the same whether or not it is encoded in UTF-8; otherwise evaluates to 0. UTF-8 invariant characters can be copied as-is when converting to/from UTF-8, saving time.cp is Unicode if above 255; otherwise is platform-native.
boolUVCHR_IS_INVARIANT(UV cp)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 code point from 0..IV_MAX as input.IV_MAX is typically 0x7FFF_FFFF in a 32-bit word.
It is possible to forbid or warn on non-Unicode code points, or those that may be problematic by using"uvchr_to_utf8_flags".
U8*uvchr_to_utf8(U8 *d, UV uv)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 code point from 0..IV_MAX as input.IV_MAX 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.UNICODE_DISALLOW_ILLEGAL_INTERCHANGE restricts the allowed inputs to the strict UTF-8 traditionally defined by Unicode. Similarly,UNICODE_WARN_ILLEGAL_C9_INTERCHANGE andUNICODE_DISALLOW_ILLEGAL_C9_INTERCHANGE are shortcuts to select the above-Unicode and surrogate flags, but not the non-character ones, as defined inUnicode Corrigendum #9. See"Noncharacter code points" in perlunicode.
Extremely high code points were never specified in any standard, and require an extension to UTF-8 to express, which Perl does. It is likely that programs written in something other than Perl would not be able to read files that contain these; nor would Perl understand files written by something that uses a different extension. For these reasons, there is a separate set of flags that can warn and/or disallow these extremely high code points, even if other above-Unicode ones are accepted. They are theUNICODE_WARN_PERL_EXTENDED andUNICODE_DISALLOW_PERL_EXTENDED flags. For more information see"UTF8_GOT_PERL_EXTENDED". Of courseUNICODE_DISALLOW_SUPER will treat all above-Unicode code points, including these, as malformations. (Note that the Unicode standard considers anything above 0x10FFFF to be illegal, but there are standards predating it that allow up to 0x7FFF_FFFF (2**31 -1))
A somewhat misleadingly named synonym forUNICODE_WARN_PERL_EXTENDED is retained for backward compatibility:UNICODE_WARN_ABOVE_31_BIT. Similarly,UNICODE_DISALLOW_ABOVE_31_BIT is usable instead of the more accurately namedUNICODE_DISALLOW_PERL_EXTENDED. The names are misleading because on EBCDIC platforms,these flags can apply to code points that actually do fit in 31 bits. The new names accurately describe the situation in all cases.
U8*uvchr_to_utf8_flags(U8 *d, UV uv, UV flags)NOTE: this function is experimental and may change or be removed without notice.
THIS FUNCTION SHOULD BE USED IN ONLY VERY SPECIALIZED CIRCUMSTANCES.
Most code should use"uvchr_to_utf8_flags"() rather than call this directly.
This function is for code that wants any warning and/or error messages to be returned to the caller rather than be displayed. All messages that would have been displayed if all lexcial warnings are enabled will be returned.
It is just like"uvchr_to_utf8_flags" but it takes an extra parameter placed after all the others,msgs. If this parameter is 0, this function behaves identically to"uvchr_to_utf8_flags". Otherwise,msgs should be a pointer to anHV * variable, in which this function creates a new HV to contain any appropriate messages. The hash has three key-value pairs, as follows:
textThe text of the message as aSVpv.
warn_categoriesThe warning category (or categories) packed into aSVuv.
flagA single flag bit associated with this message, in aSVuv. The bit corresponds to some bit in the*errors return value, such asUNICODE_GOT_SURROGATE.
It's important to note that specifying this parameter as non-null will cause any warnings this function would otherwise generate to be suppressed, and instead be placed in*msgs. The caller can check the lexical warnings state (or not) when choosing what to do with the returned messages.
The caller, of course, is responsible for freeing any returned HV.
U8*uvchr_to_utf8_flags_msgs(U8 *d, UV uv, UV flags, HV ** msgs)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, const 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)Like"utf8_to_uvchr_buf", but should only be called when it is known that the next character in the input UTF-8 strings is well-formed (e.g., it passes"isUTF8_CHAR". Surrogates, non-character code points, and non-Unicode code points are allowed.
UVvalid_utf8_to_uvchr(const U8 *s, STRLEN *retlen)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;Returns a boolean as to whether or not warnings are enabled for the warning categoryw. If the category is by default enabled even if not within the scope ofuse warnings, instead use the"ckWARN_d" macro.
boolckWARN(U32 w)Like"ckWARN", but takes two warnings categories as input, and returns TRUE if either is enabled. If either category is by default enabled even if not within the scope ofuse warnings, instead use the"ckWARN2_d" macro. The categories must be completely independent, one may not be subclassed from the other.
boolckWARN2(U32 w1, U32 w2)Like"ckWARN2", but takes three warnings categories as input, and returns TRUE if any is enabled. If any of the categories is by default enabled even if not within the scope ofuse warnings, instead use the"ckWARN3_d" macro. The categories must be completely independent, one may not be subclassed from any other.
boolckWARN3(U32 w1, U32 w2, U32 w3)Like"ckWARN3", but takes four warnings categories as input, and returns TRUE if any is enabled. If any of the categories is by default enabled even if not within the scope ofuse warnings, instead use the"ckWARN4_d" macro. The categories must be completely independent, one may not be subclassed from any other.
boolckWARN4(U32 w1, U32 w2, U32 w3, U32 w4)Like"ckWARN", but for use if and only if the warning category is by default enabled even if not within the scope ofuse warnings.
boolckWARN_d(U32 w)Like"ckWARN2", but for use if and only if either warning category is by default enabled even if not within the scope ofuse warnings.
boolckWARN2_d(U32 w1, U32 w2)Like"ckWARN3", but for use if and only if any of the warning categories is by default enabled even if not within the scope ofuse warnings.
boolckWARN3_d(U32 w1, U32 w2, U32 w3)Like"ckWARN4", but for use if and only if any of the warning categories is by default enabled even if not within the scope ofuse warnings.
boolckWARN4_d(U32 w1, U32 w2, U32 w3, U32 w4)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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