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NAME
perlapi - autogenerated documentation for the perl public API
DESCRIPTION
This file contains the documentation of the perl public API generated by embed.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. Any functions not listed here are 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.
Note that all Perl API global variables must be referenced with the "PL_" prefix. 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.
Note that Perl can be compiled and run under EBCDIC (See perlebcdic) or ASCII. Most of the documentation
(and even comments in the code) ignore the EBCDIC possibility. For almost all purposes the differences
are transparent. As an example, under EBCDIC, instead of UTF-8, UTF-EBCDIC is used to encode Unicode
strings, and so whenever this documentation refers to "utf8" (and variants of that name, including in
function names), it also (essentially transparently) means "UTF-EBCDIC". But the ordinals of characters
differ between ASCII, EBCDIC, and the UTF- encodings, and a string encoded in UTF-EBCDIC may occupy more
bytes than in UTF-8.
The listing below is alphabetical, case insensitive.
Gimme" Values
GIMME A backward-compatible version of "GIMME_V" which can only return "G_SCALAR" or "G_ARRAY"; in a
void context, it returns "G_SCALAR". Deprecated. Use "GIMME_V" instead.
U32 GIMME
GIMME_V The XSUB-writer's equivalent to Perl's "wantarray". Returns "G_VOID", "G_SCALAR" or "G_ARRAY"
for void, scalar or list context, respectively. See perlcall for a usage example.
U32 GIMME_V
G_ARRAY Used to indicate list context. See "GIMME_V", "GIMME" and perlcall.
G_DISCARD
Indicates that arguments returned from a callback should be discarded. See perlcall.
G_EVAL Used to force a Perl "eval" wrapper around a callback. See perlcall.
G_NOARGS
Indicates that no arguments are being sent to a callback. See perlcall.
G_SCALAR
Used to indicate scalar context. See "GIMME_V", "GIMME", and perlcall.
G_VOID Used to indicate void context. See "GIMME_V" and perlcall.
Array Manipulation Functions
AvFILL Same as "av_top_index()". Deprecated, use "av_top_index()" instead.
int AvFILL(AV* av)
av_clear
Clears an array, making it empty. Does not free the memory the av uses to store its list of
scalars. If any destructors are triggered as a result, the av itself may be freed when this
function returns.
Perl equivalent: "@myarray = ();".
void av_clear(AV *av)
av_create_and_push
Push an SV onto the end of the array, creating the array if necessary. A small internal helper
function to remove a commonly duplicated idiom.
NOTE: this function is experimental and may change or be removed without notice.
void av_create_and_push(AV **const avp,
SV *const val)
av_create_and_unshift_one
Unshifts an SV onto the beginning of the array, creating the array if necessary. A small
internal helper function to remove a commonly duplicated idiom.
NOTE: this function is experimental and may change or be removed without notice.
SV** av_create_and_unshift_one(AV **const avp,
SV *const val)
av_delete
Deletes the element indexed by "key" from the array, makes the element mortal, and returns it.
If "flags" equals "G_DISCARD", the element is freed and null is returned. Perl equivalent: "my
$elem = delete($myarray[$idx]);" for the non-"G_DISCARD" version and a void-context
"delete($myarray[$idx]);" for the "G_DISCARD" version.
SV* av_delete(AV *av, I32 key, I32 flags)
av_exists
Returns true if the element indexed by "key" has been initialized.
This relies on the fact that uninitialized array elements are set to &PL_sv_undef.
Perl equivalent: "exists($myarray[$key])".
bool av_exists(AV *av, I32 key)
av_extend
Pre-extend an array. The "key" is the index to which the array should be extended.
void av_extend(AV *av, I32 key)
av_fetch
Returns the SV at the specified index in the array. The "key" is the index. If lval is true,
you are guaranteed to get a real SV back (in case it wasn't real before), which you can then
modify. Check that the return value is non-null before dereferencing it to a "SV*".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how
to use this function on tied arrays.
The rough perl equivalent is $myarray[$idx].
SV** av_fetch(AV *av, I32 key, I32 lval)
av_fill Set the highest index in the array to the given number, equivalent to Perl's "$#array = $fill;".
The number of elements in the an array will be "fill + 1" after av_fill() returns. If the array
was previously shorter, then the additional elements appended are set to "PL_sv_undef". If the
array was longer, then the excess elements are freed. "av_fill(av, -1)" is the same as
"av_clear(av)".
void av_fill(AV *av, I32 fill)
av_len Same as "av_top_index". Returns the highest index in the array. Note that the return value is
+1 what its name implies it returns; and hence differs in meaning from what the similarly named
"sv_len" returns.
I32 av_len(AV *av)
av_make Creates a new AV and populates it with a list of SVs. The SVs are copied into the array, so they
may be freed after the call to av_make. The new AV will have a reference count of 1.
Perl equivalent: "my @new_array = ($scalar1, $scalar2, $scalar3...);"
AV* av_make(I32 size, SV **strp)
av_pop Removes one SV from the end of the array, reducing its size by one and returning the SV
(transferring control of one reference count) to the caller. Returns &PL_sv_undef if the array
is empty.
Perl equivalent: "pop(@myarray);"
SV* av_pop(AV *av)
av_push Pushes an SV onto the end of the array. The array will grow automatically to accommodate the
addition. This takes ownership of one reference count.
Perl equivalent: "push @myarray, $elem;".
void av_push(AV *av, SV *val)
av_shift
Shifts an SV off the beginning of the array. Returns &PL_sv_undef if the array is empty.
Perl equivalent: "shift(@myarray);"
SV* av_shift(AV *av)
av_store
Stores an SV in an array. The array index is specified as "key". The return value will be NULL
if the operation failed or if the value did not need to be actually stored within the array (as
in the case of tied arrays). Otherwise, it can be dereferenced to get the "SV*" that was stored
there (= "val")).
Note that the caller is responsible for suitably incrementing the reference count of "val" before
the call, and decrementing it if the function returned NULL.
Approximate Perl equivalent: "$myarray[$key] = $val;".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how
to use this function on tied arrays.
SV** av_store(AV *av, I32 key, SV *val)
av_tindex
Same as "av_top_index()".
int av_tindex(AV* av)
av_top_index
Returns the highest index in the array. The number of elements in the array is "av_top_index(av)
+ 1". Returns -1 if the array is empty.
The Perl equivalent for this is $#myarray.
(A slightly shorter form is "av_tindex".)
I32 av_top_index(AV *av)
av_undef
Undefines the array. Frees the memory used by the av to store its list of scalars. If any
destructors are triggered as a result, the av itself may be freed.
void av_undef(AV *av)
av_unshift
Unshift the given number of "undef" values onto the beginning of the array. The array will grow
automatically to accommodate the addition. You must then use "av_store" to assign values to
these new elements.
Perl equivalent: "unshift @myarray, ( (undef) x $n );"
void av_unshift(AV *av, I32 num)
get_av Returns the AV of the specified Perl global or package array with the given name (so it won't
work on lexical variables). "flags" are passed to "gv_fetchpv". If "GV_ADD" is set and the Perl
variable does not exist then it will be created. If "flags" is zero and the variable does not
exist then NULL is returned.
Perl equivalent: "@{"$name"}".
NOTE: the perl_ form of this function is deprecated.
AV* get_av(const char *name, I32 flags)
newAV Creates a new AV. The reference count is set to 1.
Perl equivalent: "my @array;".
AV* newAV()
sortsv Sort an array. Here is an example:
sortsv(AvARRAY(av), av_top_index(av)+1, Perl_sv_cmp_locale);
Currently this always uses mergesort. See sortsv_flags for a more flexible routine.
void sortsv(SV** array, size_t num_elts,
SVCOMPARE_t cmp)
sortsv_flags
Sort an array, with various options.
void sortsv_flags(SV** array, size_t num_elts,
SVCOMPARE_t cmp, U32 flags)
Callback Functions
call_argv
Performs a callback to the specified named and package-scoped Perl subroutine with "argv" (a
NULL-terminated array of strings) as arguments. See perlcall.
Approximate Perl equivalent: "&{"$sub_name"}(@$argv)".
NOTE: the perl_ form of this function is deprecated.
I32 call_argv(const char* sub_name, I32 flags,
char** argv)
call_method
Performs a callback to the specified Perl method. The blessed object must be on the stack. See
perlcall.
NOTE: the perl_ form of this function is deprecated.
I32 call_method(const char* methname, I32 flags)
call_pv Performs a callback to the specified Perl sub. See perlcall.
NOTE: the perl_ form of this function is deprecated.
I32 call_pv(const char* sub_name, I32 flags)
call_sv Performs a callback to the Perl sub whose name is in the SV. See perlcall.
NOTE: the perl_ form of this function is deprecated.
I32 call_sv(SV* sv, VOL I32 flags)
ENTER Opening bracket on a callback. See "LEAVE" and perlcall.
ENTER;
eval_pv Tells Perl to "eval" the given string and return an SV* result.
NOTE: the perl_ form of this function is deprecated.
SV* eval_pv(const char* p, I32 croak_on_error)
eval_sv Tells Perl to "eval" the string in the SV. It supports the same flags as "call_sv", with the
obvious exception of G_EVAL. See perlcall.
NOTE: the perl_ form of this function is deprecated.
I32 eval_sv(SV* sv, I32 flags)
FREETMPS
Closing bracket for temporaries on a callback. See "SAVETMPS" and perlcall.
FREETMPS;
LEAVE Closing bracket on a callback. See "ENTER" and perlcall.
LEAVE;
SAVETMPS
Opening bracket for temporaries on a callback. See "FREETMPS" and perlcall.
SAVETMPS;
Character case changing
toLOWER Converts the specified character to lowercase, if possible; otherwise returns the input character
itself.
char toLOWER(char ch)
toUPPER Converts the specified character to uppercase, if possible; otherwise returns the input character
itself.
char toUPPER(char ch)
Character classes
This section is about functions (really macros) that classify characters into types, such as punctuation
versus alphabetic, etc. Most of these are analogous to regular expression character classes. (See
"POSIX Character Classes" in perlrecharclass.) There are several variants for each class. (Not all
macros have all variants; each item below lists the ones valid for it.) None are affected by "use
bytes", and only the ones with "LC" in the name are affected by the current locale.
The base function, e.g., "isALPHA()", takes an octet (either a "char" or a "U8") 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.
Variant "isFOO_A" (e.g., "isALPHA_A()") is identical to the base function with no suffix "_A".
Variant "isFOO_L1" imposes the Latin-1 (or EBCDIC equivlalent) character set onto the platform. That is,
the code points that are ASCII are unaffected, since ASCII is a subset of Latin-1. But the non-ASCII
code points are treated as if they are Latin-1 characters. For example, "isWORDCHAR_L1()" will return
true when called with the code point 0xDF, which is a word character in both ASCII and EBCDIC (though it
represent different characters in each).
Variant "isFOO_uni" is like the "isFOO_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_uni(0x100)" returns TRUE, since 0x100 is LATIN CAPITAL LETTER A WITH MACRON in
Unicode, and is a word character.
Variant "isFOO_utf8" is like "isFOO_uni", but the input is a pointer to a (known to be well-formed) UTF-8
encoded string ("U8*" or "char*"). The classification of just the first (possibly multi-byte) character
in the string is tested.
Variant "isFOO_LC" is like the "isFOO_A" and "isFOO_L1" variants, but uses the C library function that
gives the named classification instead of hard-coded rules. For example, "isDIGIT_LC()" returns the
result of calling "isdigit()". This means that the result is based on the current locale, which is what
"LC" in the name stands for. FALSE is always returned if the input won't fit into an octet.
Variant "isFOO_LC_uvchr" is like "isFOO_LC", but is defined on any UV. It returns the same as "isFOO_LC"
for input code points less than 256, and returns the hard-coded, not-affected-by-locale, Unicode results
for larger ones.
Variant "isFOO_LC_utf8" is like "isFOO_LC_uvchr", but the input is a pointer to a (known to be well-
formed) UTF-8 encoded string ("U8*" or "char*"). The classification of just the first (possibly multi-
byte) character in the string is tested.
isALPHA Returns a boolean indicating whether the specified character is an alphabetic character,
analogous to "m/[[:alpha:]]/". See the top of this section for an explanation of variants
"isALPHA_A", "isALPHA_L1", "isALPHA_uni", "isALPHA_utf8", "isALPHA_LC", "isALPHA_LC_uvchr", and
"isALPHA_LC_utf8".
bool isALPHA(char ch)
isALPHANUMERIC
Returns a boolean indicating whether the specified character is a either an alphabetic character
or decimal digit, analogous to "m/[[:alnum:]]/". See the top of this section for an explanation
of variants "isALPHANUMERIC_A", "isALPHANUMERIC_L1", "isALPHANUMERIC_uni", "isALPHANUMERIC_utf8",
"isALPHANUMERIC_LC", "isALPHANUMERIC_LC_uvchr", and "isALPHANUMERIC_LC_utf8".
bool isALPHANUMERIC(char ch)
isASCII Returns a boolean indicating whether the specified character is one of the 128 characters in the
ASCII character set, analogous to "m/[[:ascii:]]/". On non-ASCII platforms, it returns TRUE iff
this character corresponds to an ASCII character. Variants "isASCII_A()" and "isASCII_L1()" are
identical to "isASCII()". See the top of this section for an explanation of variants
"isASCII_uni", "isASCII_utf8", "isASCII_LC", "isASCII_LC_uvchr", and "isASCII_LC_utf8". Note,
however, that some platforms do not have the C library routine "isascii()". In these cases, the
variants whose names contain "LC" are the same as the corresponding ones without.
bool isASCII(char ch)
isBLANK Returns a boolean indicating whether the specified character is a character considered to be a
blank, analogous to "m/[[:blank:]]/". See the top of this section for an explanation of variants
"isBLANK_A", "isBLANK_L1", "isBLANK_uni", "isBLANK_utf8", "isBLANK_LC", "isBLANK_LC_uvchr", and
"isBLANK_LC_utf8". Note, however, that some platforms do not have the C library routine
"isblank()". In these cases, the variants whose names contain "LC" are the same as the
corresponding ones without.
bool isBLANK(char ch)
isCNTRL Returns a boolean indicating whether the specified character is a control character, analogous to
"m/[[:cntrl:]]/". See the top of this section for an explanation of variants "isCNTRL_A",
"isCNTRL_L1", "isCNTRL_uni", "isCNTRL_utf8", "isCNTRL_LC", "isCNTRL_LC_uvchr", and
"isCNTRL_LC_utf8" On EBCDIC platforms, you almost always want to use the "isCNTRL_L1" variant.
bool isCNTRL(char ch)
isDIGIT Returns a boolean indicating whether the specified character is a digit, analogous to
"m/[[:digit:]]/". Variants "isDIGIT_A" and "isDIGIT_L1" are identical to "isDIGIT". See the top
of this section for an explanation of variants "isDIGIT_uni", "isDIGIT_utf8", "isDIGIT_LC",
"isDIGIT_LC_uvchr", and "isDIGIT_LC_utf8".
bool isDIGIT(char ch)
isGRAPH Returns a boolean indicating whether the specified character is a graphic character, analogous to
"m/[[:graph:]]/". See the top of this section for an explanation of variants "isGRAPH_A",
"isGRAPH_L1", "isGRAPH_uni", "isGRAPH_utf8", "isGRAPH_LC", "isGRAPH_LC_uvchr", and
"isGRAPH_LC_utf8".
bool isGRAPH(char ch)
isIDCONT
Returns a boolean indicating whether the specified character can be the second or succeeding
character of an identifier. This is very close to, but not quite the same as the official
Unicode property "XID_Continue". The difference is that this returns true only if the input
character also matches "isWORDCHAR". See the top of this section for an explanation of variants
"isIDCONT_A", "isIDCONT_L1", "isIDCONT_uni", "isIDCONT_utf8", "isIDCONT_LC", "isIDCONT_LC_uvchr",
and "isIDCONT_LC_utf8".
bool isIDCONT(char ch)
isIDFIRST
Returns a boolean indicating whether the specified character can be the first character of an
identifier. This is very close to, but not quite the same as the official Unicode property
"XID_Start". The difference is that this returns true only if the input character also matches
"isWORDCHAR". See the top of this section for an explanation of variants "isIDFIRST_A",
"isIDFIRST_L1", "isIDFIRST_uni", "isIDFIRST_utf8", "isIDFIRST_LC", "isIDFIRST_LC_uvchr", and
"isIDFIRST_LC_utf8".
bool isIDFIRST(char ch)
isLOWER Returns a boolean indicating whether the specified character is a lowercase character, analogous
to "m/[[:lower:]]/". See the top of this section for an explanation of variants "isLOWER_A",
"isLOWER_L1", "isLOWER_uni", "isLOWER_utf8", "isLOWER_LC", "isLOWER_LC_uvchr", and
"isLOWER_LC_utf8".
bool isLOWER(char ch)
isOCTAL Returns a boolean indicating whether the specified character is an octal digit, [0-7]. The only
two variants are "isOCTAL_A" and "isOCTAL_L1"; each is identical to "isOCTAL".
bool isOCTAL(char ch)
isPRINT Returns a boolean indicating whether the specified character is a printable character, analogous
to "m/[[:print:]]/". See the top of this section for an explanation of variants "isPRINT_A",
"isPRINT_L1", "isPRINT_uni", "isPRINT_utf8", "isPRINT_LC", "isPRINT_LC_uvchr", and
"isPRINT_LC_utf8".
bool isPRINT(char ch)
isPSXSPC
(short for Posix Space) Starting in 5.18, this is identical (experimentally) in all its forms to
the corresponding "isSPACE()" macros. ("Experimentally" means that this change may be backed out
in 5.20 or 5.22 if field experience indicates that it was unwise.) The locale forms of this
macro are identical to their corresponding "isSPACE()" forms in all Perl releases. In releases
prior to 5.18, the non-locale forms differ from their "isSPACE()" forms only in that the
"isSPACE()" forms don't match a Vertical Tab, and the "isPSXSPC()" forms do. Otherwise they are
identical. Thus this macro is analogous to what "m/[[:space:]]/" matches in a regular
expression. See the top of this section for an explanation of variants "isPSXSPC_A",
"isPSXSPC_L1", "isPSXSPC_uni", "isPSXSPC_utf8", "isPSXSPC_LC", "isPSXSPC_LC_uvchr", and
"isPSXSPC_LC_utf8".
bool isPSXSPC(char ch)
isPUNCT Returns a boolean indicating whether the specified character is a punctuation character,
analogous to "m/[[:punct:]]/". Note that the definition of what is punctuation isn't as
straightforward as one might desire. See "POSIX Character Classes" in perlrecharclass for
details. See the top of this section for an explanation of variants "isPUNCT_A", "isPUNCT_L1",
"isPUNCT_uni", "isPUNCT_utf8", "isPUNCT_LC", "isPUNCT_LC_uvchr", and "isPUNCT_LC_utf8".
bool isPUNCT(char ch)
isSPACE Returns a boolean indicating whether the specified character is a whitespace character. This is
analogous to what "m/\s/" matches in a regular expression. Starting in Perl 5.18
(experimentally), this also matches what "m/[[:space:]]/" does. ("Experimentally" means that
this change may be backed out in 5.20 or 5.22 if field experience indicates that it was unwise.)
Prior to 5.18, only the locale forms of this macro (the ones with "LC" in their names) matched
precisely what "m/[[:space:]]/" does. In those releases, the only difference, in the non-locale
variants, was that "isSPACE()" did not match a vertical tab. (See "isPSXSPC" for a macro that
matches a vertical tab in all releases.) See the top of this section for an explanation of
variants "isSPACE_A", "isSPACE_L1", "isSPACE_uni", "isSPACE_utf8", "isSPACE_LC",
"isSPACE_LC_uvchr", and "isSPACE_LC_utf8".
bool isSPACE(char ch)
isUPPER Returns a boolean indicating whether the specified character is an uppercase character, analogous
to "m/[[:upper:]]/". See the top of this section for an explanation of variants "isUPPER_A",
"isUPPER_L1", "isUPPER_uni", "isUPPER_utf8", "isUPPER_LC", "isUPPER_LC_uvchr", and
"isUPPER_LC_utf8".
bool isUPPER(char ch)
isWORDCHAR
Returns a boolean indicating whether the specified character is a character that is a word
character, analogous to what "m/\w/" and "m/[[:word:]]/" match in a regular expression. A word
character is an alphabetic character, a decimal digit, a connecting punctuation character (such
as an underscore), or a "mark" character that attaches to one of those (like some sort of
accent). "isALNUM()" is a synonym provided for backward compatibility, even though a word
character includes more than the standard C language meaning of alphanumeric. See the top of
this section for an explanation of variants "isWORDCHAR_A", "isWORDCHAR_L1", "isWORDCHAR_uni",
"isWORDCHAR_utf8", "isWORDCHAR_LC", "isWORDCHAR_LC_uvchr", and "isWORDCHAR_LC_utf8".
bool isWORDCHAR(char ch)
isXDIGIT
Returns a boolean indicating whether the specified character is a hexadecimal digit. In the
ASCII range these are "[0-9A-Fa-f]". Variants "isXDIGIT_A()" and "isXDIGIT_L1()" are identical
to "isXDIGIT()". See the top of this section for an explanation of variants "isXDIGIT_uni",
"isXDIGIT_utf8", "isXDIGIT_LC", "isXDIGIT_LC_uvchr", and "isXDIGIT_LC_utf8".
bool isXDIGIT(char ch)
Cloning an interpreter
perl_clone
Create and return a new interpreter by cloning the current one.
perl_clone takes these flags as parameters:
CLONEf_COPY_STACKS - is used to, well, copy the stacks also, without it we only clone the data
and zero the stacks, with it we copy the stacks and the new perl interpreter is ready to run at
the exact same point as the previous one. The pseudo-fork code uses COPY_STACKS while the
threads->create doesn't.
CLONEf_KEEP_PTR_TABLE - perl_clone keeps a ptr_table with the pointer of the old variable as a
key and the new variable as a value, this allows it to check if something has been cloned and not
clone it again but rather just use the value and increase the refcount. If KEEP_PTR_TABLE is not
set then perl_clone will kill the ptr_table using the function "ptr_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, example of this code is in threads.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
)
Compile-time scope hooks
BhkDISABLE
Temporarily disable an entry in this BHK structure, by clearing the appropriate flag. which is a
preprocessor token indicating which entry to disable.
NOTE: this function is experimental and may change or be removed without notice.
void BhkDISABLE(BHK *hk, which)
BhkENABLE
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.
NOTE: this function is experimental and may change or be removed without notice.
void BhkENABLE(BHK *hk, which)
BhkENTRY_set
Set an entry in the BHK structure, and set the flags to indicate it is valid. which is a
preprocessing token indicating which entry to set. The type of ptr depends on the entry.
NOTE: this function is experimental and may change or be removed without notice.
void BhkENTRY_set(BHK *hk, which, void *ptr)
blockhook_register
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 is experimental and may change or be removed without notice.
NOTE: this function must be explicitly called as Perl_blockhook_register with an aTHX_ parameter.
void Perl_blockhook_register(pTHX_ BHK *hk)
COP Hint Hashes
cophh_2hv
Generates and returns a standard Perl hash representing the full set of key/value pairs in the
cop hints hash cophh. flags is currently unused and must be zero.
NOTE: this function is experimental and may change or be removed without notice.
HV * cophh_2hv(const COPHH *cophh, U32 flags)
cophh_copy
Make and return a complete copy of the cop hints hash cophh.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_copy(COPHH *cophh)
cophh_delete_pv
Like "cophh_delete_pvn", but takes a nul-terminated string instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_delete_pv(const COPHH *cophh,
const char *key, U32 hash,
U32 flags)
cophh_delete_pvn
Delete a key and its associated value from the cop hints hash cophh, 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 by keypv and keylen. If flags has the "COPHH_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.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_delete_pvn(COPHH *cophh,
const char *keypv,
STRLEN keylen, U32 hash,
U32 flags)
cophh_delete_pvs
Like "cophh_delete_pvn", but takes a literal string instead of a string/length pair, and no
precomputed hash.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_delete_pvs(const COPHH *cophh,
const char *key, U32 flags)
cophh_delete_sv
Like "cophh_delete_pvn", but takes a Perl scalar instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_delete_sv(const COPHH *cophh, SV *key,
U32 hash, U32 flags)
cophh_fetch_pv
Like "cophh_fetch_pvn", but takes a nul-terminated string instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
SV * cophh_fetch_pv(const COPHH *cophh,
const char *key, U32 hash,
U32 flags)
cophh_fetch_pvn
Look up the entry in the cop hints hash cophh with the key specified by keypv and keylen. If
flags has the "COPHH_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.
NOTE: this function is experimental and may change or be removed without notice.
SV * cophh_fetch_pvn(const COPHH *cophh,
const char *keypv,
STRLEN keylen, U32 hash,
U32 flags)
cophh_fetch_pvs
Like "cophh_fetch_pvn", but takes a literal string instead of a string/length pair, and no
precomputed hash.
NOTE: this function is experimental and may change or be removed without notice.
SV * cophh_fetch_pvs(const COPHH *cophh,
const char *key, U32 flags)
cophh_fetch_sv
Like "cophh_fetch_pvn", but takes a Perl scalar instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
SV * cophh_fetch_sv(const COPHH *cophh, SV *key,
U32 hash, U32 flags)
cophh_free
Discard the cop hints hash cophh, freeing all resources associated with it.
NOTE: this function is experimental and may change or be removed without notice.
void cophh_free(COPHH *cophh)
cophh_new_empty
Generate and return a fresh cop hints hash containing no entries.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_new_empty()
cophh_store_pv
Like "cophh_store_pvn", but takes a nul-terminated string instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_store_pv(const COPHH *cophh,
const char *key, U32 hash,
SV *value, U32 flags)
cophh_store_pvn
Stores a value, associated with a key, in the cop hints hash cophh, 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 by keypv and keylen. If flags has the "COPHH_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.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_store_pvn(COPHH *cophh, const char *keypv,
STRLEN keylen, U32 hash,
SV *value, U32 flags)
cophh_store_pvs
Like "cophh_store_pvn", but takes a literal string instead of a string/length pair, and no
precomputed hash.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_store_pvs(const COPHH *cophh,
const char *key, SV *value,
U32 flags)
cophh_store_sv
Like "cophh_store_pvn", but takes a Perl scalar instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
COPHH * cophh_store_sv(const COPHH *cophh, SV *key,
U32 hash, SV *value, U32 flags)
COP Hint Reading
cop_hints_2hv
Generates and returns a standard Perl hash representing the full set of hint entries in the cop
cop. flags is currently unused and must be zero.
HV * cop_hints_2hv(const COP *cop, U32 flags)
cop_hints_fetch_pv
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)
cop_hints_fetch_pvn
Look up the hint entry in the cop cop with the key specified by keypv and keylen. If flags has
the "COPHH_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)
cop_hints_fetch_pvs
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,
const char *key, U32 flags)
cop_hints_fetch_sv
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)
Custom Operators
custom_op_register
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.
void Perl_custom_op_register(pTHX_
Perl_ppaddr_t ppaddr,
const XOP *xop)
custom_op_xop
Return the XOP structure for a given custom op. This function should be considered internal to
OP_NAME and the other access macros: use them instead.
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)
XopDISABLE
Temporarily disable a member of the XOP, by clearing the appropriate flag.
void XopDISABLE(XOP *xop, which)
XopENABLE
Reenable a member of the XOP which has been disabled.
void XopENABLE(XOP *xop, which)
XopENTRY
Return a member of the XOP structure. which is a cpp token indicating which entry to return. If
the member is not set this will return a default value. The return type depends on which.
XopENTRY(XOP *xop, which)
XopENTRY_set
Set a member of the XOP structure. which is a cpp token indicating which entry to set. See
"Custom Operators" in perlguts for details about the available members and how they are used.
void XopENTRY_set(XOP *xop, which, value)
XopFLAGS
Return the XOP's flags.
U32 XopFLAGS(XOP *xop)
CV Manipulation Functions
CvSTASH Returns the stash of the CV. A stash is the symbol table hash, containing the package-scoped
variables in the package where the subroutine was defined. For more information, see perlguts.
This also has a special use with XS AUTOLOAD subs. See "Autoloading with XSUBs" in perlguts.
HV* CvSTASH(CV* cv)
get_cv Uses "strlen" to get the length of "name", then calls "get_cvn_flags".
NOTE: the perl_ form of this function is deprecated.
CV* get_cv(const char* name, I32 flags)
get_cvn_flags
Returns the CV of the specified Perl subroutine. "flags" are passed to "gv_fetchpvn_flags". If
"GV_ADD" is set and the Perl subroutine does not exist then it will be declared (which has the
same effect as saying "sub name;"). If "GV_ADD" is not set and the subroutine does not exist
then NULL is returned.
NOTE: the perl_ form of this function is deprecated.
CV* get_cvn_flags(const char* name, STRLEN len,
I32 flags)
Embedding Functions
cv_clone
Clone a CV, making a lexical closure. proto supplies the prototype of the function: its code,
pad structure, and other attributes. The prototype is combined with a capture of outer lexicals
to which the code refers, which are taken from the currently-executing instance of the
immediately surrounding code.
CV * cv_clone(CV *proto)
cv_undef
Clear out all the active components of a CV. This can happen either by an explicit "undef &foo",
or by the reference count going to zero. In the former case, we keep the CvOUTSIDE pointer, so
that any anonymous children can still follow the full lexical scope chain.
void cv_undef(CV* cv)
find_rundefsv
Find and return the variable that is named $_ in the lexical scope of the currently-executing
function. This may be a lexical $_, or will otherwise be the global one.
SV * find_rundefsv()
find_rundefsvoffset
Find the position of the lexical $_ in the pad of the currently-executing function. Returns the
offset in the current pad, or "NOT_IN_PAD" if there is no lexical $_ in scope (in which case the
global one should be used instead). "find_rundefsv" is likely to be more convenient.
NOTE: the perl_ form of this function is deprecated.
PADOFFSET find_rundefsvoffset()
load_module
Loads the module whose name is pointed to by the string part of name. Note that the actual
module name, not its filename, should be given. Eg, "Foo::Bar" instead of "Foo/Bar.pm". flags
can be any of PERL_LOADMOD_DENY, PERL_LOADMOD_NOIMPORT, or PERL_LOADMOD_IMPORT_OPS (or 0 for no
flags). ver, if specified and not NULL, provides version semantics similar to "use Foo::Bar
VERSION". The optional trailing SV* arguments can be used to specify arguments to the module's
import() method, similar to "use Foo::Bar VERSION LIST". They must be terminated with a final
NULL pointer. Note that this list can only be omitted when the PERL_LOADMOD_NOIMPORT flag has
been used. Otherwise at least a single NULL pointer to designate the default import list is
required.
The reference count for each specified "SV*" parameter is decremented.
void load_module(U32 flags, SV* name, SV* ver, ...)
nothreadhook
Stub that provides thread hook for perl_destruct when there are no threads.
int nothreadhook()
pad_add_anon
Allocates a place in the currently-compiling pad (via "pad_alloc") for an anonymous function that
is lexically scoped inside the currently-compiling function. The function func is linked into
the pad, and its "CvOUTSIDE" link to the outer scope is weakened to avoid a reference loop.
One reference count is stolen, so you may need to do "SvREFCNT_inc(func)".
optype should be an opcode indicating the type of operation that the pad entry is to support.
This doesn't affect operational semantics, but is used for debugging.
PADOFFSET pad_add_anon(CV *func, I32 optype)
pad_add_name_pv
Exactly like "pad_add_name_pvn", but takes a nul-terminated string instead of a string/length
pair.
PADOFFSET pad_add_name_pv(const char *name, U32 flags,
HV *typestash, HV *ourstash)
pad_add_name_pvn
Allocates a place in the currently-compiling pad for a named lexical variable. Stores the name
and other metadata in the name part of the pad, and makes preparations to manage the variable's
lexical scoping. Returns the offset of the allocated pad slot.
namepv/namelen specify the variable's name, including leading sigil. If typestash is non-null,
the name is for a typed lexical, and this identifies the type. If ourstash is non-null, it's a
lexical reference to a package variable, and this identifies the package. The following flags
can be OR'ed together:
padadd_OUR redundantly specifies if it's a package var
padadd_STATE variable will retain value persistently
padadd_NO_DUP_CHECK skip check for lexical shadowing
PADOFFSET pad_add_name_pvn(const char *namepv,
STRLEN namelen, U32 flags,
HV *typestash, HV *ourstash)
pad_add_name_sv
Exactly like "pad_add_name_pvn", but takes the name string in the form of an SV instead of a
string/length pair.
PADOFFSET pad_add_name_sv(SV *name, U32 flags,
HV *typestash, HV *ourstash)
pad_alloc
Allocates a place in the currently-compiling pad, returning the offset of the allocated pad slot.
No name is initially attached to the pad slot. tmptype is a set of flags indicating the kind of
pad entry required, which will be set in the value SV for the allocated pad entry:
SVs_PADMY named lexical variable ("my", "our", "state")
SVs_PADTMP unnamed temporary store
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.
NOTE: this function is experimental and may change or be removed without notice.
PADOFFSET pad_alloc(I32 optype, U32 tmptype)
pad_compname_type
Looks up the type of the lexical variable at position po in the currently-compiling pad. If the
variable is typed, the stash of the class to which it is typed is returned. If not, "NULL" is
returned.
HV * pad_compname_type(PADOFFSET po)
pad_findmy_pv
Exactly like "pad_findmy_pvn", but takes a nul-terminated string instead of a string/length pair.
PADOFFSET pad_findmy_pv(const char *name, U32 flags)
pad_findmy_pvn
Given the name of a lexical variable, find its position in the currently-compiling pad.
namepv/namelen specify the variable's name, including leading sigil. flags is reserved and must
be zero. If it is not in the current pad but appears in the pad of any lexically enclosing
scope, then a pseudo-entry for it is added in the current pad. Returns the offset in the current
pad, or "NOT_IN_PAD" if no such lexical is in scope.
PADOFFSET pad_findmy_pvn(const char *namepv,
STRLEN namelen, U32 flags)
pad_findmy_sv
Exactly like "pad_findmy_pvn", but takes the name string in the form of an SV instead of a
string/length pair.
PADOFFSET pad_findmy_sv(SV *name, U32 flags)
pad_setsv
Set the value at offset po in the current (compiling or executing) pad. Use the macro
PAD_SETSV() rather than calling this function directly.
void pad_setsv(PADOFFSET po, SV *sv)
pad_sv Get the value at offset po in the current (compiling or executing) pad. Use macro PAD_SV instead
of calling this function directly.
SV * pad_sv(PADOFFSET po)
pad_tidy
Tidy up a pad at the end of compilation of the code to which it belongs. Jobs performed here
are: remove most stuff from the pads of anonsub prototypes; give it a @_; mark temporaries as
such. type indicates the kind of subroutine:
padtidy_SUB ordinary subroutine
padtidy_SUBCLONE prototype for lexical closure
padtidy_FORMAT format
NOTE: this function is experimental and may change or be removed without notice.
void pad_tidy(padtidy_type type)
perl_alloc
Allocates a new Perl interpreter. See perlembed.
PerlInterpreter* perl_alloc()
perl_construct
Initializes a new Perl interpreter. See perlembed.
void perl_construct(PerlInterpreter *my_perl)
perl_destruct
Shuts down a Perl interpreter. See perlembed.
int perl_destruct(PerlInterpreter *my_perl)
perl_free
Releases a Perl interpreter. See perlembed.
void perl_free(PerlInterpreter *my_perl)
perl_parse
Tells a Perl interpreter to parse a Perl script. See perlembed.
int perl_parse(PerlInterpreter *my_perl,
XSINIT_t xsinit, int argc,
char** argv, char** env)
perl_run
Tells a Perl interpreter to run. See perlembed.
int perl_run(PerlInterpreter *my_perl)
require_pv
Tells Perl to "require" the file named by the string argument. It is analogous to the Perl code
"eval "require '$file'"". It's even implemented that way; consider using load_module instead.
NOTE: the perl_ form of this function is deprecated.
void require_pv(const char* pv)
Functions in file dump.c
pv_display
Similar to
pv_escape(dsv,pv,cur,pvlim,PERL_PV_ESCAPE_QUOTE);
except that an additional "\0" will be appended to the string when len > cur and pv[cur] is "\0".
Note that the final string may be up to 7 chars longer than pvlim.
char* pv_display(SV *dsv, const char *pv, STRLEN cur,
STRLEN len, STRLEN pvlim)
pv_escape
Escapes at most the first "count" chars of pv and puts the results into dsv such that the size of
the escaped string will not exceed "max" chars and will not contain any incomplete escape
sequences.
If flags contains PERL_PV_ESCAPE_QUOTE then any double quotes in the string will also be escaped.
Normally the SV will be cleared before the escaped string is prepared, but when
PERL_PV_ESCAPE_NOCLEAR is set this will not occur.
If PERL_PV_ESCAPE_UNI is set then the input string is treated as Unicode, if
PERL_PV_ESCAPE_UNI_DETECT is set then the input string is scanned using "is_utf8_string()" to
determine if it is Unicode.
If PERL_PV_ESCAPE_ALL is set then all input chars will be output using "\x01F1" style escapes,
otherwise if PERL_PV_ESCAPE_NONASCII is set, only chars above 127 will be escaped using this
style; otherwise, only chars above 255 will be so escaped; other non printable chars will use
octal or common escaped patterns like "\n". Otherwise, if PERL_PV_ESCAPE_NOBACKSLASH then all
chars below 255 will be treated as printable and will be output as literals.
If PERL_PV_ESCAPE_FIRSTCHAR is set then only the first char of the string will be escaped,
regardless of max. If the output is to be in hex, then it will be returned as a plain hex
sequence. Thus the output will either be a single char, an octal escape sequence, a special
escape like "\n" or a hex value.
If PERL_PV_ESCAPE_RE is set then the escape char used will be a '%' and not a '\\'. This is
because regexes very often contain backslashed sequences, whereas '%' is not a particularly
common character in patterns.
Returns a pointer to the escaped text as held by dsv.
char* pv_escape(SV *dsv, char const * const str,
const STRLEN count, const STRLEN max,
STRLEN * const escaped,
const U32 flags)
pv_pretty
Converts a string into something presentable, handling escaping via pv_escape() and supporting
quoting and ellipses.
If the PERL_PV_PRETTY_QUOTE flag is set then the result will be double quoted with any double
quotes in the string escaped. Otherwise if the PERL_PV_PRETTY_LTGT flag is set then the result be
wrapped in angle brackets.
If the PERL_PV_PRETTY_ELLIPSES flag is set and not all characters in string were output then an
ellipsis "..." will be appended to the string. Note that this happens AFTER it has been quoted.
If start_color is non-null then it will be inserted after the opening quote (if there is one) but
before the escaped text. If end_color is non-null then it will be inserted after the escaped text
but before any quotes or ellipses.
Returns a pointer to the prettified text as held by dsv.
char* pv_pretty(SV *dsv, char const * const str,
const STRLEN count, const STRLEN max,
char const * const start_color,
char const * const end_color,
const U32 flags)
Functions in file mathoms.c
custom_op_desc
Return the description of a given custom op. This was once used by the OP_DESC macro, but is no
longer: it has only been kept for compatibility, and should not be used.
const char * custom_op_desc(const OP *o)
custom_op_name
Return the name for a given custom op. This was once used by the OP_NAME macro, but is no longer:
it has only been kept for compatibility, and should not be used.
const char * custom_op_name(const OP *o)
gv_fetchmethod
See "gv_fetchmethod_autoload".
GV* gv_fetchmethod(HV* stash, const char* name)
pack_cat
The engine implementing pack() Perl function. Note: parameters next_in_list and flags are not
used. This call should not be used; use packlist instead.
void pack_cat(SV *cat, const char *pat,
const char *patend, SV **beglist,
SV **endlist, SV ***next_in_list,
U32 flags)
sv_2pvbyte_nolen
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 the "SvPVbyte_nolen" macro.
char* sv_2pvbyte_nolen(SV* sv)
sv_2pvutf8_nolen
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 the "SvPVutf8_nolen" macro.
char* sv_2pvutf8_nolen(SV* sv)
sv_2pv_nolen
Like "sv_2pv()", but doesn't return the length too. You should usually use the macro wrapper
"SvPV_nolen(sv)" instead.
char* sv_2pv_nolen(SV* sv)
sv_catpvn_mg
Like "sv_catpvn", but also handles 'set' magic.
void sv_catpvn_mg(SV *sv, const char *ptr,
STRLEN len)
sv_catsv_mg
Like "sv_catsv", but also handles 'set' magic.
void sv_catsv_mg(SV *dsv, SV *ssv)
sv_force_normal
Undo various types of fakery on an SV: if the PV is a shared string, make a private copy; if
we're a ref, stop refing; if we're a glob, downgrade to an xpvmg. See also
"sv_force_normal_flags".
void sv_force_normal(SV *sv)
sv_iv A private implementation of the "SvIVx" macro for compilers which can't cope with complex macro
expressions. Always use the macro instead.
IV sv_iv(SV* sv)
sv_nolocking
Dummy routine which "locks" an SV when there is no locking module present. Exists to avoid test
for a NULL function pointer and because it could potentially warn under some level of strict-
ness.
"Superseded" by sv_nosharing().
void sv_nolocking(SV *sv)
sv_nounlocking
Dummy routine which "unlocks" an SV when there is no locking module present. Exists to avoid
test for a NULL function pointer and because it could potentially warn under some level of
strict-ness.
"Superseded" by sv_nosharing().
void sv_nounlocking(SV *sv)
sv_nv A private implementation of the "SvNVx" macro for compilers which can't cope with complex macro
expressions. Always use the macro instead.
NV sv_nv(SV* sv)
sv_pv Use the "SvPV_nolen" macro instead
char* sv_pv(SV *sv)
sv_pvbyte
Use "SvPVbyte_nolen" instead.
char* sv_pvbyte(SV *sv)
sv_pvbyten
A private implementation of the "SvPVbyte" macro for compilers which can't cope with complex
macro expressions. Always use the macro instead.
char* sv_pvbyten(SV *sv, STRLEN *lp)
sv_pvn A private implementation of the "SvPV" macro for compilers which can't cope with complex macro
expressions. Always use the macro instead.
char* sv_pvn(SV *sv, STRLEN *lp)
sv_pvutf8
Use the "SvPVutf8_nolen" macro instead
char* sv_pvutf8(SV *sv)
sv_pvutf8n
A private implementation of the "SvPVutf8" macro for compilers which can't cope with complex
macro expressions. Always use the macro instead.
char* sv_pvutf8n(SV *sv, STRLEN *lp)
sv_taint
Taint an SV. Use "SvTAINTED_on" instead.
void sv_taint(SV* sv)
sv_unref
Unsets the RV status of the SV, and decrements the reference count of whatever was being
referenced by the RV. This can almost be thought of as a reversal of "newSVrv". This is
"sv_unref_flags" with the "flag" being zero. See "SvROK_off".
void sv_unref(SV* sv)
sv_usepvn
Tells an SV to use "ptr" to find its string value. Implemented by calling "sv_usepvn_flags" with
"flags" of 0, hence does not handle 'set' magic. See "sv_usepvn_flags".
void sv_usepvn(SV* sv, char* ptr, STRLEN len)
sv_usepvn_mg
Like "sv_usepvn", but also handles 'set' magic.
void sv_usepvn_mg(SV *sv, char *ptr, STRLEN len)
sv_uv A private implementation of the "SvUVx" macro for compilers which can't cope with complex macro
expressions. Always use the macro instead.
UV sv_uv(SV* sv)
unpack_str
The engine implementing unpack() Perl function. Note: parameters strbeg, new_s and ocnt are not
used. This call should not be used, use unpackstring instead.
I32 unpack_str(const char *pat, const char *patend,
const char *s, const char *strbeg,
const char *strend, char **new_s,
I32 ocnt, U32 flags)
Functions in file op.c
alloccopstash
Available only under threaded builds, this function allocates an entry in "PL_stashpad" for the
stash passed to it.
NOTE: this function is experimental and may change or be removed without notice.
PADOFFSET alloccopstash(HV *hv)
op_contextualize
Applies a syntactic context to an op tree representing an expression. o is the op tree, and
context must be "G_SCALAR", "G_ARRAY", or "G_VOID" to specify the context to apply. The modified
op tree is returned.
OP * op_contextualize(OP *o, I32 context)
Functions in file perl.h
PERL_SYS_INIT
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.
void PERL_SYS_INIT(int *argc, char*** argv)
PERL_SYS_INIT3
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.
void PERL_SYS_INIT3(int *argc, char*** argv,
char*** env)
PERL_SYS_TERM
Provides system-specific clean up of the C runtime environment after running Perl interpreters.
This should be called only once, after freeing any remaining Perl interpreters.
void PERL_SYS_TERM()
Functions in file pp_ctl.c
caller_cx
The XSUB-writer's equivalent of caller(). The returned "PERL_CONTEXT" structure can be
interrogated to find all the information returned to Perl by "caller". Note that XSUBs don't get
a stack frame, so "caller_cx(0, NULL)" will return information for the immediately-surrounding
Perl code.
This function skips over the automatic calls to &DB::sub made on the behalf of the debugger. If
the stack frame requested was a sub called by "DB::sub", the return value will be the frame for
the call to "DB::sub", since that has the correct line number/etc. for the call site. If dbcxp is
non-"NULL", it will be set to a pointer to the frame for the sub call itself.
const PERL_CONTEXT * caller_cx(
I32 level,
const PERL_CONTEXT **dbcxp
)
find_runcv
Locate the CV corresponding to the currently executing sub or eval. If db_seqp is non_null, skip
CVs that are in the DB package and populate *db_seqp with the cop sequence number at the point
that the DB:: code was entered. (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)
Functions in file pp_pack.c
packlist
The engine implementing pack() Perl function.
void packlist(SV *cat, const char *pat,
const char *patend, SV **beglist,
SV **endlist)
unpackstring
The engine implementing the unpack() Perl function.
Using the template pat..patend, this function unpacks the string s..strend into a number of
mortal SVs, which it pushes onto the perl argument (@_) stack (so you will need to issue a
"PUTBACK" before and "SPAGAIN" after the call to this function). It returns the number of pushed
elements.
The strend and patend pointers should point to the byte following the last character of each
string.
Although this function returns its values on the perl argument stack, it doesn't take any
parameters from that stack (and thus in particular there's no need to do a PUSHMARK before
calling it, unlike "call_pv" for example).
I32 unpackstring(const char *pat,
const char *patend, const char *s,
const char *strend, U32 flags)
Functions in file pp_sys.c
setdefout
Sets PL_defoutgv, the default file handle for output, to the passed in typeglob. As PL_defoutgv
"owns" a reference on its typeglob, the reference count of the passed in typeglob is increased by
one, and the reference count of the typeglob that PL_defoutgv points to is decreased by one.
void setdefout(GV* gv)
Functions in file utf8.h
ibcmp_utf8
This is a synonym for (! foldEQ_utf8())
I32 ibcmp_utf8(const char *s1, char **pe1, UV l1,
bool u1, const char *s2, char **pe2,
UV l2, bool u2)
Functions in file util.h
ibcmp This is a synonym for (! foldEQ())
I32 ibcmp(const char* a, const char* b, I32 len)
ibcmp_locale
This is a synonym for (! foldEQ_locale())
I32 ibcmp_locale(const char* a, const char* b,
I32 len)
Global Variables
PL_check
Array, indexed by opcode, of functions that will be called for the "check" phase of optree
building during compilation of Perl code. For most (but not all) types of op, once the op has
been initially built and populated with child ops it will be filtered through the check function
referenced by the appropriate element of this array. The new op is passed in as the sole
argument to the check function, and the check function returns the completed op. The check
function may (as the name suggests) check the op for validity and signal errors. It may also
initialise or modify parts of the ops, or perform more radical surgery such as adding or removing
child ops, or even throw the op away and return a different op in its place.
This array of function pointers is a convenient place to hook into the compilation process. An
XS module can put its own custom check function in place of any of the standard ones, to
influence the compilation of a particular type of op. However, a custom check function must
never fully replace a standard check function (or even a custom check function from another
module). A module modifying checking must instead wrap the preexisting check function. A custom
check function must be selective about when to apply its custom behaviour. In the usual case
where it decides not to do anything special with an op, it must chain the preexisting op
function. Check functions are thus linked in a chain, with the core's base checker at the end.
For thread safety, modules should not write directly to this array. Instead, use the function
"wrap_op_checker".
PL_keyword_plugin
Function pointer, pointing at a function used to handle extended keywords. The function should
be declared as
int keyword_plugin_function(pTHX_
char *keyword_ptr, STRLEN keyword_len,
OP **op_ptr)
The function is called from the tokeniser, whenever a possible keyword is seen. "keyword_ptr"
points at the word in the parser's input buffer, and "keyword_len" gives its length; it is not
null-terminated. The function is expected to examine the word, and possibly other state such as
%^H, to decide whether it wants to handle it as an extended keyword. If it does not, the
function should return "KEYWORD_PLUGIN_DECLINE", and the normal parser process will continue.
If the function wants to handle the keyword, it first must parse anything following the keyword
that is part of the syntax introduced by the keyword. See "Lexer interface" for details.
When a keyword is being handled, the plugin function must build a tree of "OP" structures,
representing the code that was parsed. The root of the tree must be stored in *op_ptr. The
function then returns a constant indicating the syntactic role of the construct that it has
parsed: "KEYWORD_PLUGIN_STMT" if it is a complete statement, or "KEYWORD_PLUGIN_EXPR" if it is an
expression. Note that a statement construct cannot be used inside an expression (except via "do
BLOCK" and similar), and an expression is not a complete statement (it requires at least a
terminating semicolon).
When a keyword is handled, the plugin function may also have (compile-time) side effects. It may
modify "%^H", define functions, and so on. Typically, if side effects are the main purpose of a
handler, it does not wish to generate any ops to be included in the normal compilation. In this
case it is still required to supply an op tree, but it suffices to generate a single null op.
That's how the *PL_keyword_plugin function needs to behave overall. Conventionally, however, one
does not completely replace the existing handler function. Instead, take a copy of
"PL_keyword_plugin" before assigning your own function pointer to it. Your handler function
should look for keywords that it is interested in and handle those. Where it is not interested,
it should call the saved plugin function, passing on the arguments it received. Thus
"PL_keyword_plugin" actually points at a chain of handler functions, all of which have an
opportunity to handle keywords, and only the last function in the chain (built into the Perl
core) will normally return "KEYWORD_PLUGIN_DECLINE".
NOTE: this function is experimental and may change or be removed without notice.
GV Functions
GvAV Return the AV from the GV.
AV* GvAV(GV* gv)
GvCV Return the CV from the GV.
CV* GvCV(GV* gv)
GvHV Return the HV from the GV.
HV* GvHV(GV* gv)
GvSV Return the SV from the GV.
SV* GvSV(GV* gv)
gv_const_sv
If "gv" is a typeglob whose subroutine entry is a constant sub eligible for inlining, or "gv" is
a placeholder reference that would be promoted to such a typeglob, then returns the value
returned by the sub. Otherwise, returns NULL.
SV* gv_const_sv(GV* gv)
gv_fetchmeth
Like "gv_fetchmeth_pvn", but lacks a flags parameter.
GV* gv_fetchmeth(HV* stash, const char* name,
STRLEN len, I32 level)
gv_fetchmethod_autoload
Returns the glob which contains the subroutine to call to invoke the method on the "stash". In
fact in the presence of autoloading this may be the glob for "AUTOLOAD". In this case the
corresponding variable $AUTOLOAD is already setup.
The third parameter of "gv_fetchmethod_autoload" determines whether AUTOLOAD lookup is performed
if the given method is not present: non-zero means yes, look for AUTOLOAD; zero means no, don't
look for AUTOLOAD. Calling "gv_fetchmethod" is equivalent to calling "gv_fetchmethod_autoload"
with a non-zero "autoload" parameter.
These functions grant "SUPER" token as a prefix of the method name. Note that if you want to keep
the returned glob for a long time, you need to check for it being "AUTOLOAD", since at the later
time the call may load a different subroutine due to $AUTOLOAD changing its value. Use the glob
created via a side effect to do this.
These functions have the same side-effects and as "gv_fetchmeth" with "level==0". "name" should
be writable if contains ':' or ' ''. The warning against passing the GV returned by
"gv_fetchmeth" to "call_sv" apply equally to these functions.
GV* gv_fetchmethod_autoload(HV* stash,
const char* name,
I32 autoload)
gv_fetchmeth_autoload
This is the old form of "gv_fetchmeth_pvn_autoload", which has no flags parameter.
GV* gv_fetchmeth_autoload(HV* stash,
const char* name,
STRLEN len, I32 level)
gv_fetchmeth_pv
Exactly like "gv_fetchmeth_pvn", but takes a nul-terminated string instead of a string/length
pair.
GV* gv_fetchmeth_pv(HV* stash, const char* name,
I32 level, U32 flags)
gv_fetchmeth_pvn
Returns the glob with the given "name" and a defined subroutine or "NULL". The glob lives in the
given "stash", or in the stashes accessible via @ISA and UNIVERSAL::.
The argument "level" should be either 0 or -1. If "level==0", as a side-effect creates a glob
with the given "name" in the given "stash" which in the case of success contains an alias for the
subroutine, and sets up caching info for this glob.
The only significant values for "flags" are GV_SUPER and SVf_UTF8.
GV_SUPER indicates that we want to look up the method in the superclasses of the "stash".
The GV returned from "gv_fetchmeth" may be a method cache entry, which is not visible to Perl
code. So when calling "call_sv", you should not use the GV directly; instead, you should use the
method's CV, which can be obtained from the GV with the "GvCV" macro.
GV* gv_fetchmeth_pvn(HV* stash, const char* name,
STRLEN len, I32 level,
U32 flags)
gv_fetchmeth_pvn_autoload
Same as gv_fetchmeth_pvn(), but looks for autoloaded subroutines too. Returns a glob for the
subroutine.
For an autoloaded subroutine without a GV, will create a GV even if "level < 0". For an
autoloaded subroutine without a stub, GvCV() of the result may be zero.
Currently, the only significant value for "flags" is SVf_UTF8.
GV* gv_fetchmeth_pvn_autoload(HV* stash,
const char* name,
STRLEN len, I32 level,
U32 flags)
gv_fetchmeth_pv_autoload
Exactly like "gv_fetchmeth_pvn_autoload", but takes a nul-terminated string instead of a
string/length pair.
GV* gv_fetchmeth_pv_autoload(HV* stash,
const char* name,
I32 level, U32 flags)
gv_fetchmeth_sv
Exactly like "gv_fetchmeth_pvn", but takes the name string in the form of an SV instead of a
string/length pair.
GV* gv_fetchmeth_sv(HV* stash, SV* namesv,
I32 level, U32 flags)
gv_fetchmeth_sv_autoload
Exactly like "gv_fetchmeth_pvn_autoload", but takes the name string in the form of an SV instead
of a string/length pair.
GV* gv_fetchmeth_sv_autoload(HV* stash, SV* namesv,
I32 level, U32 flags)
gv_init The old form of gv_init_pvn(). It does not work with UTF8 strings, as it has no flags parameter.
If the "multi" parameter is set, the GV_ADDMULTI flag will be passed to gv_init_pvn().
void gv_init(GV* gv, HV* stash, const char* name,
STRLEN len, int multi)
gv_init_pv
Same as gv_init_pvn(), but takes a nul-terminated string for the name instead of separate char *
and length parameters.
void gv_init_pv(GV* gv, HV* stash, const char* name,
U32 flags)
gv_init_pvn
Converts a scalar into a typeglob. This is an incoercible typeglob; assigning a reference to it
will assign to one of its slots, instead of overwriting it as happens with typeglobs created by
SvSetSV. Converting any scalar that is SvOK() may produce unpredictable results and is reserved
for perl's internal use.
"gv" is the scalar to be converted.
"stash" is the parent stash/package, if any.
"name" and "len" give the name. The name must be unqualified; that is, it must not include the
package name. If "gv" is a stash element, it is the caller's responsibility to ensure that the
name passed to this function matches the name of the element. If it does not match, perl's
internal bookkeeping will get out of sync.
"flags" can be set to SVf_UTF8 if "name" is a UTF8 string, or the return value of SvUTF8(sv). It
can also take the GV_ADDMULTI flag, which means to pretend that the GV has been seen before
(i.e., suppress "Used once" warnings).
void gv_init_pvn(GV* gv, HV* stash, const char* name,
STRLEN len, U32 flags)
gv_init_sv
Same as gv_init_pvn(), but takes an SV * for the name instead of separate char * and length
parameters. "flags" is currently unused.
void gv_init_sv(GV* gv, HV* stash, SV* namesv,
U32 flags)
gv_stashpv
Returns a pointer to the stash for a specified package. Uses "strlen" to determine the length of
"name", then calls "gv_stashpvn()".
HV* gv_stashpv(const char* name, I32 flags)
gv_stashpvn
Returns a pointer to the stash for a specified package. The "namelen" parameter indicates the
length of the "name", in bytes. "flags" is passed to "gv_fetchpvn_flags()", so if set to
"GV_ADD" then the package will be created if it does not already exist. If the package does not
exist and "flags" is 0 (or any other setting that does not create packages) then NULL is
returned.
Flags may be one of:
GV_ADD
SVf_UTF8
GV_NOADD_NOINIT
GV_NOINIT
GV_NOEXPAND
GV_ADDMG
The most important of which are probably GV_ADD and SVf_UTF8.
HV* gv_stashpvn(const char* name, U32 namelen,
I32 flags)
gv_stashpvs
Like "gv_stashpvn", but takes a literal string instead of a string/length pair.
HV* gv_stashpvs(const char* name, I32 create)
gv_stashsv
Returns a pointer to the stash for a specified package. See "gv_stashpvn".
HV* gv_stashsv(SV* sv, I32 flags)
Handy Values
Nullav Null AV pointer.
(deprecated - use "(AV *)NULL" instead)
Nullch Null character pointer. (No longer available when "PERL_CORE" is defined.)
Nullcv Null CV pointer.
(deprecated - use "(CV *)NULL" instead)
Nullhv Null HV pointer.
(deprecated - use "(HV *)NULL" instead)
Nullsv Null SV pointer. (No longer available when "PERL_CORE" is defined.)
Hash Manipulation Functions
cop_fetch_label
Returns the label attached to a cop. The flags pointer may be set to "SVf_UTF8" or 0.
NOTE: this function is experimental and may change or be removed without notice.
const char * cop_fetch_label(COP *const cop,
STRLEN *len, U32 *flags)
cop_store_label
Save a label into a "cop_hints_hash". You need to set flags to "SVf_UTF8" for a utf-8 label.
NOTE: this function is experimental and may change or be removed without notice.
void cop_store_label(COP *const cop,
const char *label, STRLEN len,
U32 flags)
get_hv Returns the HV of the specified Perl hash. "flags" are passed to "gv_fetchpv". If "GV_ADD" is
set and the Perl variable does not exist then it will be created. If "flags" is zero and the
variable does not exist then NULL is returned.
NOTE: the perl_ form of this function is deprecated.
HV* get_hv(const char *name, I32 flags)
HEf_SVKEY
This flag, used in the length slot of hash entries and magic structures, specifies the structure
contains an "SV*" pointer where a "char*" pointer is to be expected. (For information only--not
to be used).
HeHASH Returns the computed hash stored in the hash entry.
U32 HeHASH(HE* he)
HeKEY Returns the actual pointer stored in the key slot of the hash entry. The pointer may be either
"char*" or "SV*", depending on the value of "HeKLEN()". Can be assigned to. The "HePV()" or
"HeSVKEY()" macros are usually preferable for finding the value of a key.
void* HeKEY(HE* he)
HeKLEN If this is negative, and amounts to "HEf_SVKEY", it indicates the entry holds an "SV*" key.
Otherwise, holds the actual length of the key. Can be assigned to. The "HePV()" macro is usually
preferable for finding key lengths.
STRLEN HeKLEN(HE* he)
HePV Returns the key slot of the hash entry as a "char*" value, doing any necessary dereferencing of
possibly "SV*" keys. The length of the string is placed in "len" (this is a macro, so do not use
&len). If you do not care about what the length of the key is, you may use the global variable
"PL_na", though this is rather less efficient than using a local variable. Remember though, that
hash keys in perl are free to contain embedded nulls, so using "strlen()" or similar is not a
good way to find the length of hash keys. This is very similar to the "SvPV()" macro described
elsewhere in this document. See also "HeUTF8".
If you are using "HePV" to get values to pass to "newSVpvn()" to create a new SV, you should
consider using "newSVhek(HeKEY_hek(he))" as it is more efficient.
char* HePV(HE* he, STRLEN len)
HeSVKEY Returns the key as an "SV*", or "NULL" if the hash entry does not contain an "SV*" key.
SV* HeSVKEY(HE* he)
HeSVKEY_force
Returns the key as an "SV*". Will create and return a temporary mortal "SV*" if the hash entry
contains only a "char*" key.
SV* HeSVKEY_force(HE* he)
HeSVKEY_set
Sets the key to a given "SV*", taking care to set the appropriate flags to indicate the presence
of an "SV*" key, and returns the same "SV*".
SV* HeSVKEY_set(HE* he, SV* sv)
HeUTF8 Returns whether the "char *" value returned by "HePV" is encoded in UTF-8, doing any necessary
dereferencing of possibly "SV*" keys. The value returned will be 0 or non-0, not necessarily 1
(or even a value with any low bits set), so do not blindly assign this to a "bool" variable, as
"bool" may be a typedef for "char".
char* HeUTF8(HE* he)
HeVAL Returns the value slot (type "SV*") stored in the hash entry. Can be assigned to.
SV *foo= HeVAL(hv);
HeVAL(hv)= sv;
SV* HeVAL(HE* he)
HvENAME Returns the effective name of a stash, or NULL if there is none. The effective name represents a
location in the symbol table where this stash resides. It is updated automatically when packages
are aliased or deleted. A stash that is no longer in the symbol table has no effective name.
This name is preferable to "HvNAME" for use in MRO linearisations and isa caches.
char* HvENAME(HV* stash)
HvENAMELEN
Returns the length of the stash's effective name.
STRLEN HvENAMELEN(HV *stash)
HvENAMEUTF8
Returns true if the effective name is in UTF8 encoding.
unsigned char HvENAMEUTF8(HV *stash)
HvNAME Returns the package name of a stash, or NULL if "stash" isn't a stash. See "SvSTASH", "CvSTASH".
char* HvNAME(HV* stash)
HvNAMELEN
Returns the length of the stash's name.
STRLEN HvNAMELEN(HV *stash)
HvNAMEUTF8
Returns true if the name is in UTF8 encoding.
unsigned char HvNAMEUTF8(HV *stash)
hv_assert
Check that a hash is in an internally consistent state.
void hv_assert(HV *hv)
hv_clear
Frees the all the elements of a hash, leaving it empty. The XS equivalent of "%hash = ()". See
also "hv_undef".
If any destructors are triggered as a result, the hv itself may be freed.
void hv_clear(HV *hv)
hv_clear_placeholders
Clears any placeholders from a hash. If a restricted hash has any of its keys marked as readonly
and the key is subsequently deleted, the key is not actually deleted but is marked by assigning
it a value of &PL_sv_placeholder. This tags it so it will be ignored by future operations such
as iterating over the hash, but will still allow the hash to have a value reassigned to the key
at some future point. This function clears any such placeholder keys from the hash. See
Hash::Util::lock_keys() for an example of its use.
void hv_clear_placeholders(HV *hv)
hv_copy_hints_hv
A specialised version of "newHVhv" for copying "%^H". ohv must be a pointer to a hash (which may
have "%^H" magic, but should be generally non-magical), or "NULL" (interpreted as an empty hash).
The content of ohv is copied to a new hash, which has the "%^H"-specific magic added to it. A
pointer to the new hash is returned.
HV * hv_copy_hints_hv(HV *ohv)
hv_delete
Deletes a key/value pair in the hash. The value's SV is removed from the hash, made mortal, and
returned to the caller. The absolute value of "klen" is the length of the key. If "klen" is
negative the key is assumed to be in UTF-8-encoded Unicode. The "flags" value will normally be
zero; if set to G_DISCARD then NULL will be returned. NULL will also be returned if the key is
not found.
SV* hv_delete(HV *hv, const char *key, I32 klen,
I32 flags)
hv_delete_ent
Deletes a key/value pair in the hash. The value SV is removed from the hash, made mortal, and
returned to the caller. The "flags" value will normally be zero; if set to G_DISCARD then NULL
will be returned. NULL will also be returned if the key is not found. "hash" can be a valid
precomputed hash value, or 0 to ask for it to be computed.
SV* hv_delete_ent(HV *hv, SV *keysv, I32 flags,
U32 hash)
hv_exists
Returns a boolean indicating whether the specified hash key exists. The absolute value of "klen"
is the length of the key. If "klen" is negative the key is assumed to be in UTF-8-encoded
Unicode.
bool hv_exists(HV *hv, const char *key, I32 klen)
hv_exists_ent
Returns a boolean indicating whether the specified hash key exists. "hash" can be a valid
precomputed hash value, or 0 to ask for it to be computed.
bool hv_exists_ent(HV *hv, SV *keysv, U32 hash)
hv_fetch
Returns the SV which corresponds to the specified key in the hash. The absolute value of "klen"
is the length of the key. If "klen" is negative the key is assumed to be in UTF-8-encoded
Unicode. If "lval" is set then the fetch will be part of a store. This means that if there is
no value in the hash associated with the given key, then one is created and a pointer to it is
returned. The "SV*" it points to can be assigned to. But always check that the return value is
non-null before dereferencing it to an "SV*".
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how
to use this function on tied hashes.
SV** hv_fetch(HV *hv, const char *key, I32 klen,
I32 lval)
hv_fetchs
Like "hv_fetch", but takes a literal string instead of a string/length pair.
SV** hv_fetchs(HV* tb, const char* key, I32 lval)
hv_fetch_ent
Returns the hash entry which corresponds to the specified key in the hash. "hash" must be a
valid precomputed hash number for the given "key", or 0 if you want the function to compute it.
IF "lval" is set then the fetch will be part of a store. Make sure the return value is non-null
before accessing it. The return value when "hv" is a tied hash is a pointer to a static
location, so be sure to make a copy of the structure if you need to store it somewhere.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how
to use this function on tied hashes.
HE* hv_fetch_ent(HV *hv, SV *keysv, I32 lval,
U32 hash)
hv_fill Returns the number of hash buckets that happen to be in use. This function is wrapped by the
macro "HvFILL".
Previously this value was stored in the HV structure, rather than being calculated on demand.
STRLEN hv_fill(HV const *const hv)
hv_iterinit
Prepares a starting point to traverse a hash table. Returns the number of keys in the hash (i.e.
the same as "HvUSEDKEYS(hv)"). The return value is currently only meaningful for hashes without
tie magic.
NOTE: Before version 5.004_65, "hv_iterinit" used to return the number of hash buckets that
happen to be in use. If you still need that esoteric value, you can get it through the macro
"HvFILL(hv)".
I32 hv_iterinit(HV *hv)
hv_iterkey
Returns the key from the current position of the hash iterator. See "hv_iterinit".
char* hv_iterkey(HE* entry, I32* retlen)
hv_iterkeysv
Returns the key as an "SV*" from the current position of the hash iterator. The return value
will always be a mortal copy of the key. Also see "hv_iterinit".
SV* hv_iterkeysv(HE* entry)
hv_iternext
Returns entries from a hash iterator. See "hv_iterinit".
You may call "hv_delete" or "hv_delete_ent" on the hash entry that the iterator currently points
to, without losing your place or invalidating your iterator. Note that in this case the current
entry is deleted from the hash with your iterator holding the last reference to it. Your
iterator is flagged to free the entry on the next call to "hv_iternext", so you must not discard
your iterator immediately else the entry will leak - call "hv_iternext" to trigger the resource
deallocation.
HE* hv_iternext(HV *hv)
hv_iternextsv
Performs an "hv_iternext", "hv_iterkey", and "hv_iterval" in one operation.
SV* hv_iternextsv(HV *hv, char **key, I32 *retlen)
hv_iternext_flags
Returns entries from a hash iterator. See "hv_iterinit" and "hv_iternext". The "flags" value
will normally be zero; if HV_ITERNEXT_WANTPLACEHOLDERS is set the placeholders keys (for
restricted hashes) will be returned in addition to normal keys. By default placeholders are
automatically skipped over. Currently a placeholder is implemented with a value that is
&PL_sv_placeholder. Note that the implementation of placeholders and restricted hashes may
change, and the implementation currently is insufficiently abstracted for any change to be tidy.
NOTE: this function is experimental and may change or be removed without notice.
HE* hv_iternext_flags(HV *hv, I32 flags)
hv_iterval
Returns the value from the current position of the hash iterator. See "hv_iterkey".
SV* hv_iterval(HV *hv, HE *entry)
hv_magic
Adds magic to a hash. See "sv_magic".
void hv_magic(HV *hv, GV *gv, int how)
hv_scalar
Evaluates the hash in scalar context and returns the result. Handles magic when the hash is tied.
SV* hv_scalar(HV *hv)
hv_store
Stores an SV in a hash. The hash key is specified as "key" and the absolute value of "klen" is
the length of the key. If "klen" is negative the key is assumed to be in UTF-8-encoded Unicode.
The "hash" parameter is the precomputed hash value; if it is zero then Perl will compute it.
The return value will be NULL if the operation failed or if the value did not need to be actually
stored within the hash (as in the case of tied hashes). Otherwise it can be dereferenced to get
the original "SV*". Note that the caller is responsible for suitably incrementing the reference
count of "val" before the call, and decrementing it if the function returned NULL. Effectively a
successful hv_store takes ownership of one reference to "val". This is usually what you want; a
newly created SV has a reference count of one, so if all your code does is create SVs then store
them in a hash, hv_store will own the only reference to the new SV, and your code doesn't need to
do anything further to tidy up. hv_store is not implemented as a call to hv_store_ent, and does
not create a temporary SV for the key, so if your key data is not already in SV form then use
hv_store in preference to hv_store_ent.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how
to use this function on tied hashes.
SV** hv_store(HV *hv, const char *key, I32 klen,
SV *val, U32 hash)
hv_stores
Like "hv_store", but takes a literal string instead of a string/length pair and omits the hash
parameter.
SV** hv_stores(HV* tb, const char* key,
NULLOK SV* val)
hv_store_ent
Stores "val" in a hash. The hash key is specified as "key". The "hash" parameter is the
precomputed hash value; if it is zero then Perl will compute it. The return value is the new
hash entry so created. It will be NULL if the operation failed or if the value did not need to
be actually stored within the hash (as in the case of tied hashes). Otherwise the contents of
the return value can be accessed using the "He?" macros described here. Note that the caller is
responsible for suitably incrementing the reference count of "val" before the call, and
decrementing it if the function returned NULL. Effectively a successful hv_store_ent takes
ownership of one reference to "val". This is usually what you want; a newly created SV has a
reference count of one, so if all your code does is create SVs then store them in a hash,
hv_store will own the only reference to the new SV, and your code doesn't need to do anything
further to tidy up. Note that hv_store_ent only reads the "key"; unlike "val" it does not take
ownership of it, so maintaining the correct reference count on "key" is entirely the caller's
responsibility. hv_store is not implemented as a call to hv_store_ent, and does not create a
temporary SV for the key, so if your key data is not already in SV form then use hv_store in
preference to hv_store_ent.
See "Understanding the Magic of Tied Hashes and Arrays" in perlguts for more information on how
to use this function on tied hashes.
HE* hv_store_ent(HV *hv, SV *key, SV *val, U32 hash)
hv_undef
Undefines the hash. The XS equivalent of "undef(%hash)".
As well as freeing all the elements of the hash (like hv_clear()), this also frees any auxiliary
data and storage associated with the hash.
If any destructors are triggered as a result, the hv itself may be freed.
See also "hv_clear".
void hv_undef(HV *hv)
newHV Creates a new HV. The reference count is set to 1.
HV* newHV()
Hook manipulation
wrap_op_checker
Puts a C function into the chain of check functions for a specified op type. This is the
preferred way to manipulate the "PL_check" array. opcode specifies which type of op is to be
affected. new_checker is a pointer to the C function that is to be added to that opcode's check
chain, and old_checker_p points to the storage location where a pointer to the next function in
the chain will be stored. The value of new_pointer is written into the "PL_check" array, while
the value previously stored there is written to *old_checker_p.
"PL_check" is global to an entire process, and a module wishing to hook op checking may find
itself invoked more than once per process, typically in different threads. To handle that
situation, this function is idempotent. The location *old_checker_p must initially (once per
process) contain a null pointer. A C variable of static duration (declared at file scope,
typically also marked "static" to give it internal linkage) will be implicitly initialised
appropriately, if it does not have an explicit initialiser. This function will only actually
modify the check chain if it finds *old_checker_p to be null. This function is also thread safe
on the small scale. It uses appropriate locking to avoid race conditions in accessing
"PL_check".
When this function is called, the function referenced by new_checker must be ready to be called,
except for *old_checker_p being unfilled. In a threading situation, new_checker may be called
immediately, even before this function has returned. *old_checker_p will always be appropriately
set before new_checker is called. If new_checker decides not to do anything special with an op
that it is given (which is the usual case for most uses of op check hooking), it must chain the
check function referenced by *old_checker_p.
If you want to influence compilation of calls to a specific subroutine, then use
"cv_set_call_checker" rather than hooking checking of all "entersub" ops.
void wrap_op_checker(Optype opcode,
Perl_check_t new_checker,
Perl_check_t *old_checker_p)
Lexer interface
lex_bufutf8
Indicates whether the octets in the lexer buffer ("PL_parser->linestr") should be interpreted as
the UTF-8 encoding of Unicode characters. If not, they should be interpreted as Latin-1
characters. This is analogous to the "SvUTF8" flag for scalars.
In UTF-8 mode, it is not guaranteed that the lexer buffer actually contains valid UTF-8. Lexing
code must be robust in the face of invalid encoding.
The actual "SvUTF8" flag of the "PL_parser->linestr" scalar is significant, but not the whole
story regarding the input character encoding. Normally, when a file is being read, the scalar
contains octets and its "SvUTF8" flag is off, but the octets should be interpreted as UTF-8 if
the "use utf8" pragma is in effect. During a string eval, however, the scalar may have the
"SvUTF8" flag on, and in this case its octets should be interpreted as UTF-8 unless the "use
bytes" pragma is in effect. This logic may change in the future; use this function instead of
implementing the logic yourself.
NOTE: this function is experimental and may change or be removed without notice.
bool lex_bufutf8()
lex_discard_to
Discards the first part of the "PL_parser->linestr" buffer, up to ptr. The remaining content of
the buffer will be moved, and all pointers into the buffer updated appropriately. ptr must not
be later in the buffer than the position of "PL_parser->bufptr": it is not permitted to discard
text that has yet to be lexed.
Normally it is not necessarily to do this directly, because it suffices to use the implicit
discarding behaviour of "lex_next_chunk" and things based on it. However, if a token stretches
across multiple lines, and the lexing code has kept multiple lines of text in the buffer for that
purpose, then after completion of the token it would be wise to explicitly discard the now-
unneeded earlier lines, to avoid future multi-line tokens growing the buffer without bound.
NOTE: this function is experimental and may change or be removed without notice.
void lex_discard_to(char *ptr)
lex_grow_linestr
Reallocates the lexer buffer ("PL_parser->linestr") to accommodate at least len octets (including
terminating NUL). Returns a pointer to the reallocated buffer. This is necessary before making
any direct modification of the buffer that would increase its length. "lex_stuff_pvn" provides a
more convenient way to insert text into the buffer.
Do not use "SvGROW" or "sv_grow" directly on "PL_parser->linestr"; this function updates all of
the lexer's variables that point directly into the buffer.
NOTE: this function is experimental and may change or be removed without notice.
char * lex_grow_linestr(STRLEN len)
lex_next_chunk
Reads in the next chunk of text to be lexed, appending it to "PL_parser->linestr". This should
be called when lexing code has looked to the end of the current chunk and wants to know more. It
is usual, but not necessary, for lexing to have consumed the entirety of the current chunk at
this time.
If "PL_parser->bufptr" is pointing to the very end of the current chunk (i.e., the current chunk
has been entirely consumed), normally the current chunk will be discarded at the same time that
the new chunk is read in. If flags includes "LEX_KEEP_PREVIOUS", 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.
NOTE: this function is experimental and may change or be removed without notice.
bool lex_next_chunk(U32 flags)
lex_peek_unichar
Looks ahead one (Unicode) character in the text currently being lexed. Returns the codepoint
(unsigned integer value) of the next character, or -1 if lexing has reached the end of the input
text. To consume the peeked character, use "lex_read_unichar".
If the next character is in (or extends into) the next chunk of input text, the next chunk will
be read in. Normally the current chunk will be discarded at the same time, but if flags includes
"LEX_KEEP_PREVIOUS" 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.
NOTE: this function is experimental and may change or be removed without notice.
I32 lex_peek_unichar(U32 flags)
lex_read_space
Reads optional spaces, in Perl style, in the text currently being lexed. The spaces may include
ordinary whitespace characters and Perl-style comments. "#line" directives are processed if
encountered. "PL_parser->bufptr" is moved past the spaces, so that it points at a non-space
character (or the end of the input text).
If spaces extend into the next chunk of input text, the next chunk will be read in. Normally the
current chunk will be discarded at the same time, but if flags includes "LEX_KEEP_PREVIOUS" then
the current chunk will not be discarded.
NOTE: this function is experimental and may change or be removed without notice.
void lex_read_space(U32 flags)
lex_read_to
Consume text in the lexer buffer, from "PL_parser->bufptr" up to ptr. This advances
"PL_parser->bufptr" to match ptr, performing the correct bookkeeping whenever a newline character
is passed. This is the normal way to consume lexed text.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level
functions "lex_peek_unichar" and "lex_read_unichar".
NOTE: this function is experimental and may change or be removed without notice.
void lex_read_to(char *ptr)
lex_read_unichar
Reads the next (Unicode) character in the text currently being lexed. Returns the codepoint
(unsigned integer value) of the character read, and moves "PL_parser->bufptr" past the character,
or returns -1 if lexing has reached the end of the input text. To non-destructively examine the
next character, use "lex_peek_unichar" instead.
If the next character is in (or extends into) the next chunk of input text, the next chunk will
be read in. Normally the current chunk will be discarded at the same time, but if flags includes
"LEX_KEEP_PREVIOUS" 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.
NOTE: this function is experimental and may change or be removed without notice.
I32 lex_read_unichar(U32 flags)
lex_start
Creates and initialises a new lexer/parser state object, supplying a context in which to lex and
parse from a new source of Perl code. A pointer to the new state object is placed in
"PL_parser". An entry is made on the save stack so that upon unwinding the new state object will
be destroyed and the former value of "PL_parser" will be restored. Nothing else need be done to
clean up the parsing context.
The code to be parsed comes from line and rsfp. line, if non-null, provides a string (in SV
form) containing code to be parsed. A copy of the string is made, so subsequent modification of
line does not affect parsing. rsfp, if non-null, provides an input stream from which code will
be read to be parsed. If both are non-null, the code in line comes first and must consist of
complete lines of input, and rsfp supplies the remainder of the source.
The flags parameter is reserved for future use. Currently it is only used by perl internally, so
extensions should always pass zero.
NOTE: this function is experimental and may change or be removed without notice.
void lex_start(SV *line, PerlIO *rsfp, U32 flags)
lex_stuff_pv
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current
lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing
code that runs later will see the characters as if they had appeared in the input. It is not
recommended to do this as part of normal parsing, and most uses of this facility run the risk of
the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by octets starting at pv and continuing to the first
nul. These octets are interpreted as either UTF-8 or Latin-1, according to whether the
"LEX_STUFF_UTF8" flag is set in flags. The characters are recoded for the lexer buffer,
according to how the buffer is currently being interpreted ("lex_bufutf8"). If it is not
convenient to nul-terminate a string to be inserted, the "lex_stuff_pvn" function is more
appropriate.
NOTE: this function is experimental and may change or be removed without notice.
void lex_stuff_pv(const char *pv, U32 flags)
lex_stuff_pvn
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current
lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing
code that runs later will see the characters as if they had appeared in the input. It is not
recommended to do this as part of normal parsing, and most uses of this facility run the risk of
the inserted characters being interpreted in an unintended manner.
The string to be inserted is represented by len octets starting at pv. These octets are
interpreted as either UTF-8 or Latin-1, according to whether the "LEX_STUFF_UTF8" flag is set in
flags. The characters are recoded for the lexer buffer, according to how the buffer is currently
being interpreted ("lex_bufutf8"). If a string to be inserted is available as a Perl scalar, the
"lex_stuff_sv" function is more convenient.
NOTE: this function is experimental and may change or be removed without notice.
void lex_stuff_pvn(const char *pv, STRLEN len,
U32 flags)
lex_stuff_pvs
Like "lex_stuff_pvn", but takes a literal string instead of a string/length pair.
NOTE: this function is experimental and may change or be removed without notice.
void lex_stuff_pvs(const char *pv, U32 flags)
lex_stuff_sv
Insert characters into the lexer buffer ("PL_parser->linestr"), immediately after the current
lexing point ("PL_parser->bufptr"), reallocating the buffer if necessary. This means that lexing
code that runs later will see the characters as if they had appeared in the input. It is not
recommended to do this as part of normal parsing, and most uses of this facility run the risk of
the inserted characters being interpreted in an unintended manner.
The string to be inserted is the string value of sv. The characters are recoded for the lexer
buffer, according to how the buffer is currently being interpreted ("lex_bufutf8"). If a string
to be inserted is not already a Perl scalar, the "lex_stuff_pvn" function avoids the need to
construct a scalar.
NOTE: this function is experimental and may change or be removed without notice.
void lex_stuff_sv(SV *sv, U32 flags)
lex_unstuff
Discards text about to be lexed, from "PL_parser->bufptr" up to ptr. Text following ptr will be
moved, and the buffer shortened. This hides the discarded text from any lexing code that runs
later, as if the text had never appeared.
This is not the normal way to consume lexed text. For that, use "lex_read_to".
NOTE: this function is experimental and may change or be removed without notice.
void lex_unstuff(char *ptr)
parse_arithexpr
Parse a Perl arithmetic expression. This may contain operators of precedence down to the bit
shift operators. The expression must be followed (and thus terminated) either by a comparison or
lower-precedence operator or by something that would normally terminate an expression such as
semicolon. If flags includes "PARSE_OPTIONAL" 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.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_arithexpr(U32 flags)
parse_barestmt
Parse a single unadorned Perl statement. This may be a normal imperative statement or a
declaration that has compile-time effect. It does not include any label or other affixture. It
is up to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set
to reflect the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement
is null, for example if it was actually a subroutine definition (which has compile-time side
effects). If not null, it will be ops directly implementing the statement, suitable to pass to
"newSTATEOP". It will not normally include a "nextstate" or equivalent op (except for those
embedded in a scope contained entirely within the statement).
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is
returned anyway. The error is reflected in the parser state, normally resulting in a single
exception at the top level of parsing which covers all the compilation errors that occurred.
Some compilation errors, however, will throw an exception immediately.
The flags parameter is reserved for future use, and must always be zero.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_barestmt(U32 flags)
parse_block
Parse a single complete Perl code block. This consists of an opening brace, a sequence of
statements, and a closing brace. The block constitutes a lexical scope, so "my" variables and
various compile-time effects can be contained within it. It is up to the caller to ensure that
the dynamic parser state ("PL_parser" et al) is correctly set to reflect the source of the code
to be parsed and the lexical context for the statement.
The op tree representing the code block is returned. This is always a real op, never a null
pointer. It will normally be a "lineseq" list, including "nextstate" or equivalent ops. No ops
to construct any kind of runtime scope are included by virtue of it being a block.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is
returned anyway. The error is reflected in the parser state, normally resulting in a single
exception at the top level of parsing which covers all the compilation errors that occurred.
Some compilation errors, however, will throw an exception immediately.
The flags parameter is reserved for future use, and must always be zero.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_block(U32 flags)
parse_fullexpr
Parse a single complete Perl expression. This allows the full expression grammar, including the
lowest-precedence operators such as "or". The expression must be followed (and thus terminated)
by a token that an expression would normally be terminated by: end-of-file, closing bracketing
punctuation, semicolon, or one of the keywords that signals a postfix expression-statement
modifier. If flags includes "PARSE_OPTIONAL" 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.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_fullexpr(U32 flags)
parse_fullstmt
Parse a single complete Perl statement. This may be a normal imperative statement or a
declaration that has compile-time effect, and may include optional labels. It is up to the
caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to reflect
the source of the code to be parsed and the lexical context for the statement.
The op tree representing the statement is returned. This may be a null pointer if the statement
is null, for example if it was actually a subroutine definition (which has compile-time side
effects). If not null, it will be the result of a "newSTATEOP" call, normally including a
"nextstate" or equivalent op.
If an error occurs in parsing or compilation, in most cases a valid op tree (most likely null) is
returned anyway. The error is reflected in the parser state, normally resulting in a single
exception at the top level of parsing which covers all the compilation errors that occurred.
Some compilation errors, however, will throw an exception immediately.
The flags parameter is reserved for future use, and must always be zero.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_fullstmt(U32 flags)
parse_label
Parse a single label, possibly optional, of the type that may prefix a Perl statement. It is up
to the caller to ensure that the dynamic parser state ("PL_parser" et al) is correctly set to
reflect the source of the code to be parsed. If flags includes "PARSE_OPTIONAL" 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.
NOTE: this function is experimental and may change or be removed without notice.
SV * parse_label(U32 flags)
parse_listexpr
Parse a Perl list expression. This may contain operators of precedence down to the comma
operator. The expression must be followed (and thus terminated) either by a low-precedence logic
operator such as "or" or by something that would normally terminate an expression such as
semicolon. If flags includes "PARSE_OPTIONAL" 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.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_listexpr(U32 flags)
parse_stmtseq
Parse a sequence of zero or more Perl statements. These may be normal imperative statements,
including optional labels, or declarations that have compile-time effect, or any mixture thereof.
The statement sequence ends when a closing brace or end-of-file is encountered in a place where a
new statement could have validly started. It is up to the caller to ensure that the dynamic
parser state ("PL_parser" et al) is correctly set to reflect the source of the code to be parsed
and the lexical context for the statements.
The op tree representing the statement sequence is returned. This may be a null pointer if the
statements were all null, for example if there were no statements or if there were only
subroutine definitions (which have compile-time side effects). If not null, it will be a
"lineseq" list, normally including "nextstate" or equivalent ops.
If an error occurs in parsing or compilation, in most cases a valid op tree is returned anyway.
The error is reflected in the parser state, normally resulting in a single exception at the top
level of parsing which covers all the compilation errors that occurred. Some compilation errors,
however, will throw an exception immediately.
The flags parameter is reserved for future use, and must always be zero.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_stmtseq(U32 flags)
parse_termexpr
Parse a Perl term expression. This may contain operators of precedence down to the assignment
operators. The expression must be followed (and thus terminated) either by a comma or lower-
precedence operator or by something that would normally terminate an expression such as
semicolon. If flags includes "PARSE_OPTIONAL" 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.
NOTE: this function is experimental and may change or be removed without notice.
OP * parse_termexpr(U32 flags)
PL_parser
Pointer to a structure encapsulating the state of the parsing operation currently in progress.
The pointer can be locally changed to perform a nested parse without interfering with the state
of an outer parse. Individual members of "PL_parser" have their own documentation.
PL_parser->bufend
Direct pointer to the end of the chunk of text currently being lexed, the end of the lexer
buffer. This is equal to "SvPVX(PL_parser->linestr) + SvCUR(PL_parser->linestr)". A NUL
character (zero octet) is always located at the end of the buffer, and does not count as part of
the buffer's contents.
NOTE: this function is experimental and may change or be removed without notice.
PL_parser->bufptr
Points to the current position of lexing inside the lexer buffer. Characters around this point
may be freely examined, within the range delimited by "SvPVX("PL_parser->linestr")" and
"PL_parser->bufend". The octets of the buffer may be intended to be interpreted as either UTF-8
or Latin-1, as indicated by "lex_bufutf8".
Lexing code (whether in the Perl core or not) moves this pointer past the characters that it
consumes. It is also expected to perform some bookkeeping whenever a newline character is
consumed. This movement can be more conveniently performed by the function "lex_read_to", which
handles newlines appropriately.
Interpretation of the buffer's octets can be abstracted out by using the slightly higher-level
functions "lex_peek_unichar" and "lex_read_unichar".
NOTE: this function is experimental and may change or be removed without notice.
PL_parser->linestart
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.
PL_parser->linestr
Buffer scalar containing the chunk currently under consideration of the text currently being
lexed. This is always a plain string scalar (for which "SvPOK" is true). It is not intended to
be used as a scalar by normal scalar means; instead refer to the buffer directly by the pointer
variables described below.
The lexer maintains various "char*" pointers to things in the "PL_parser->linestr" buffer. If
"PL_parser->linestr" is ever reallocated, all of these pointers must be updated. Don't attempt
to do this manually, but rather use "lex_grow_linestr" if you need to reallocate the buffer.
The content of the text chunk in the buffer is commonly exactly one complete line of input, up to
and including a newline terminator, but there are situations where it is otherwise. The octets
of the buffer may be intended to be interpreted as either UTF-8 or Latin-1. The function
"lex_bufutf8" tells you which. Do not use the "SvUTF8" flag on this scalar, which may disagree
with it.
For direct examination of the buffer, the variable "PL_parser->bufend" points to the end of the
buffer. The current lexing position is pointed to by "PL_parser->bufptr". Direct use of these
pointers is usually preferable to examination of the scalar through normal scalar means.
NOTE: this function is experimental and may change or be removed without notice.
Magical Functions
mg_clear
Clear something magical that the SV represents. See "sv_magic".
int mg_clear(SV* sv)
mg_copy Copies the magic from one SV to another. See "sv_magic".
int mg_copy(SV *sv, SV *nsv, const char *key,
I32 klen)
mg_find Finds the magic pointer for type matching the SV. See "sv_magic".
MAGIC* mg_find(const SV* sv, int type)
mg_findext
Finds the magic pointer of "type" with the given "vtbl" for the "SV". See "sv_magicext".
MAGIC* mg_findext(const SV* sv, int type,
const MGVTBL *vtbl)
mg_free Free any magic storage used by the SV. See "sv_magic".
int mg_free(SV* sv)
mg_free_type
Remove any magic of type how from the SV sv. See "sv_magic".
void mg_free_type(SV *sv, int how)
mg_get Do magic before a value is retrieved from the SV. The type of SV must be >= SVt_PVMG. See
"sv_magic".
int mg_get(SV* sv)
mg_length
This function is deprecated.
It reports on the SV's length in bytes, calling length magic if available, but does not set the
UTF8 flag on the sv. It will fall back to 'get' magic if there is no 'length' magic, but with no
indication as to whether it called 'get' magic. It assumes the sv is a PVMG or higher. Use
sv_len() instead.
U32 mg_length(SV* sv)
mg_magical
Turns on the magical status of an SV. See "sv_magic".
void mg_magical(SV* sv)
mg_set Do magic after a value is assigned to the SV. See "sv_magic".
int mg_set(SV* sv)
SvGETMAGIC
Invokes "mg_get" on an SV if it has 'get' magic. For example, this will call "FETCH" on a tied
variable. This macro evaluates its argument more than once.
void SvGETMAGIC(SV* sv)
SvLOCK Arranges for a mutual exclusion lock to be obtained on sv if a suitable module has been loaded.
void SvLOCK(SV* sv)
SvSETMAGIC
Invokes "mg_set" on an SV if it has 'set' magic. This is necessary after modifying a scalar, in
case it is a magical variable like $| or a tied variable (it calls "STORE"). This macro
evaluates its argument more than once.
void SvSETMAGIC(SV* sv)
SvSetMagicSV
Like "SvSetSV", but does any set magic required afterwards.
void SvSetMagicSV(SV* dsb, SV* ssv)
SvSetMagicSV_nosteal
Like "SvSetSV_nosteal", but does any set magic required afterwards.
void SvSetMagicSV_nosteal(SV* dsv, SV* ssv)
SvSetSV Calls "sv_setsv" if dsv is not the same as ssv. May evaluate arguments more than once.
void SvSetSV(SV* dsb, SV* ssv)
SvSetSV_nosteal
Calls a non-destructive version of "sv_setsv" if dsv is not the same as ssv. May evaluate
arguments more than once.
void SvSetSV_nosteal(SV* dsv, SV* ssv)
SvSHARE Arranges for sv to be shared between threads if a suitable module has been loaded.
void SvSHARE(SV* sv)
SvUNLOCK
Releases a mutual exclusion lock on sv if a suitable module has been loaded.
void SvUNLOCK(SV* sv)
Memory Management
Copy The XSUB-writer's interface to the C "memcpy" function. The "src" is the source, "dest" is the
destination, "nitems" is the number of items, and "type" is the type. May fail on overlapping
copies. See also "Move".
void Copy(void* src, void* dest, int nitems, type)
CopyD Like "Copy" but returns dest. Useful for encouraging compilers to tail-call optimise.
void * CopyD(void* src, void* dest, int nitems, type)
Move The XSUB-writer's interface to the C "memmove" function. The "src" is the source, "dest" is the
destination, "nitems" is the number of items, and "type" is the type. Can do overlapping moves.
See also "Copy".
void Move(void* src, void* dest, int nitems, type)
MoveD Like "Move" but returns dest. Useful for encouraging compilers to tail-call optimise.
void * MoveD(void* src, void* dest, int nitems, type)
Newx The XSUB-writer's interface to the C "malloc" function.
In 5.9.3, Newx() and friends replace the older New() API, and drops the first parameter, x, a
debug aid which allowed callers to identify themselves. This aid has been superseded by a new
build option, PERL_MEM_LOG (see "PERL_MEM_LOG" in perlhacktips). The older API is still there
for use in XS modules supporting older perls.
void Newx(void* ptr, int nitems, type)
Newxc The XSUB-writer's interface to the C "malloc" function, with cast. See also "Newx".
void Newxc(void* ptr, int nitems, type, cast)
Newxz The XSUB-writer's interface to the C "malloc" function. The allocated memory is zeroed with
"memzero". See also "Newx".
void Newxz(void* ptr, int nitems, type)
Poison PoisonWith(0xEF) for catching access to freed memory.
void Poison(void* dest, int nitems, type)
PoisonFree
PoisonWith(0xEF) for catching access to freed memory.
void PoisonFree(void* dest, int nitems, type)
PoisonNew
PoisonWith(0xAB) for catching access to allocated but uninitialized memory.
void PoisonNew(void* dest, int nitems, type)
PoisonWith
Fill up memory with a byte pattern (a byte repeated over and over again) that hopefully catches
attempts to access uninitialized memory.
void PoisonWith(void* dest, int nitems, type,
U8 byte)
Renew The XSUB-writer's interface to the C "realloc" function.
void Renew(void* ptr, int nitems, type)
Renewc The XSUB-writer's interface to the C "realloc" function, with cast.
void Renewc(void* ptr, int nitems, type, cast)
Safefree
The XSUB-writer's interface to the C "free" function.
void Safefree(void* ptr)
savepv Perl's version of "strdup()". Returns a pointer to a newly allocated string which is a duplicate
of "pv". The size of the string is determined by "strlen()". The memory allocated for the new
string can be freed with the "Safefree()" function.
char* savepv(const char* pv)
savepvn Perl's version of what "strndup()" would be if it existed. Returns a pointer to a newly allocated
string which is a duplicate of the first "len" bytes from "pv", plus a trailing NUL byte. The
memory allocated for the new string can be freed with the "Safefree()" function.
char* savepvn(const char* pv, I32 len)
savepvs Like "savepvn", but takes a literal string instead of a string/length pair.
char* savepvs(const char* s)
savesharedpv
A version of "savepv()" which allocates the duplicate string in memory which is shared between
threads.
char* savesharedpv(const char* pv)
savesharedpvn
A version of "savepvn()" which allocates the duplicate string in memory which is shared between
threads. (With the specific difference that a NULL pointer is not acceptable)
char* savesharedpvn(const char *const pv,
const STRLEN len)
savesharedpvs
A version of "savepvs()" which allocates the duplicate string in memory which is shared between
threads.
char* savesharedpvs(const char* s)
savesharedsvpv
A version of "savesharedpv()" which allocates the duplicate string in memory which is shared
between threads.
char* savesharedsvpv(SV *sv)
savesvpv
A version of "savepv()"/"savepvn()" which gets the string to duplicate from the passed in SV
using "SvPV()"
char* savesvpv(SV* sv)
StructCopy
This is an architecture-independent macro to copy one structure to another.
void StructCopy(type *src, type *dest, type)
Zero The XSUB-writer's interface to the C "memzero" function. The "dest" is the destination, "nitems"
is the number of items, and "type" is the type.
void Zero(void* dest, int nitems, type)
ZeroD Like "Zero" but returns dest. Useful for encouraging compilers to tail-call optimise.
void * ZeroD(void* dest, int nitems, type)
Miscellaneous Functions
fbm_compile
Analyses the string in order to make fast searches on it using fbm_instr() -- the Boyer-Moore
algorithm.
void fbm_compile(SV* sv, U32 flags)
fbm_instr
Returns the location of the SV in the string delimited by "big" and "bigend". It returns "NULL"
if the string can't be found. The "sv" does not have to be fbm_compiled, but the search will not
be as fast then.
char* fbm_instr(unsigned char* big,
unsigned char* bigend, SV* littlestr,
U32 flags)
foldEQ Returns true if the leading len bytes of the strings s1 and s2 are the same case-insensitively;
false otherwise. Uppercase and lowercase ASCII range bytes match themselves and their opposite
case counterparts. Non-cased and non-ASCII range bytes match only themselves.
I32 foldEQ(const char* a, const char* b, I32 len)
foldEQ_locale
Returns true if the leading len bytes of the strings s1 and s2 are the same case-insensitively in
the current locale; false otherwise.
I32 foldEQ_locale(const char* a, const char* b,
I32 len)
form 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, ...)
getcwd_sv
Fill the sv with current working directory
int getcwd_sv(SV* sv)
mess 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, ...)
mess_sv Expands a message, intended for the user, to include an indication of the current location in the
code, if the message does not already appear to be complete.
"basemsg" is the initial message or object. If it is a reference, it will be used as-is and will
be the result of this function. Otherwise it is used as a string, and if it already ends with a
newline, it is taken to be complete, and the result of this function will be the same string. If
the message does not end with a newline, then a segment such as "at foo.pl line 37" will be
appended, and possibly other clauses indicating the current state of execution. The resulting
message will end with a dot and a newline.
Normally, the resulting message is returned in a new mortal SV. During global destruction a
single SV may be shared between uses of this function. If "consume" is true, then the function
is permitted (but not required) to modify and return "basemsg" instead of allocating a new SV.
SV * mess_sv(SV *basemsg, bool consume)
my_snprintf
The C library "snprintf" functionality, if available and standards-compliant (uses "vsnprintf",
actually). However, if the "vsnprintf" is not available, will unfortunately use the unsafe
"vsprintf" which can overrun the buffer (there is an overrun check, but that may be too late).
Consider using "sv_vcatpvf" instead, or getting "vsnprintf".
int my_snprintf(char *buffer, const Size_t len,
const char *format, ...)
my_sprintf
The C library "sprintf", wrapped if necessary, to ensure that it will return the length of the
string written to the buffer. Only rare pre-ANSI systems need the wrapper function - usually this
is a direct call to "sprintf".
int my_sprintf(char *buffer, const char *pat, ...)
my_vsnprintf
The C library "vsnprintf" if available and standards-compliant. However, if if the "vsnprintf"
is not available, will unfortunately use the unsafe "vsprintf" which can overrun the buffer
(there is an overrun check, but that may be too late). Consider using "sv_vcatpvf" instead, or
getting "vsnprintf".
int my_vsnprintf(char *buffer, const Size_t len,
const char *format, va_list ap)
new_version
Returns a new version object based on the passed in SV:
SV *sv = new_version(SV *ver);
Does not alter the passed in ver SV. See "upg_version" if you want to upgrade the SV.
SV* new_version(SV *ver)
prescan_version
Validate that a given string can be parsed as a version object, but doesn't actually perform the
parsing. Can use either strict or lax validation rules. Can optionally set a number of hint
variables to save the parsing code some time when tokenizing.
const char* prescan_version(const char *s, bool strict,
const char** errstr,
bool *sqv,
int *ssaw_decimal,
int *swidth, bool *salpha)
READ_XDIGIT
Returns the value of an ASCII-range hex digit and advances the string pointer. Behaviour is only
well defined when isXDIGIT(*str) is true.
U8 READ_XDIGIT(char str*)
scan_version
Returns a pointer to the next character after the parsed version string, as well as upgrading the
passed in SV to an RV.
Function must be called with an already existing SV like
sv = newSV(0);
s = scan_version(s, SV *sv, bool qv);
Performs some preprocessing to the string to ensure that it has the correct characteristics of a
version. Flags the object if it contains an underscore (which denotes this is an alpha version).
The boolean qv denotes that the version should be interpreted as if it had multiple decimals,
even if it doesn't.
const char* scan_version(const char *s, SV *rv, bool qv)
strEQ Test two strings to see if they are equal. Returns true or false.
bool strEQ(char* s1, char* s2)
strGE Test two strings to see if the first, "s1", is greater than or equal to the second, "s2".
Returns true or false.
bool strGE(char* s1, char* s2)
strGT Test two strings to see if the first, "s1", is greater than the second, "s2". Returns true or
false.
bool strGT(char* s1, char* s2)
strLE Test two strings to see if the first, "s1", is less than or equal to the second, "s2". Returns
true or false.
bool strLE(char* s1, char* s2)
strLT Test two strings to see if the first, "s1", is less than the second, "s2". Returns true or
false.
bool strLT(char* s1, char* s2)
strNE Test two strings to see if they are different. Returns true or false.
bool strNE(char* s1, char* s2)
strnEQ Test two strings to see if they are equal. The "len" parameter indicates the number of bytes to
compare. Returns true or false. (A wrapper for "strncmp").
bool strnEQ(char* s1, char* s2, STRLEN len)
strnNE Test two strings to see if they are different. The "len" parameter indicates the number of bytes
to compare. Returns true or false. (A wrapper for "strncmp").
bool strnNE(char* s1, char* s2, STRLEN len)
sv_destroyable
Dummy routine which reports that object can be destroyed when there is no sharing module present.
It ignores its single SV argument, and returns 'true'. Exists to avoid test for a NULL function
pointer and because it could potentially warn under some level of strict-ness.
bool sv_destroyable(SV *sv)
sv_nosharing
Dummy routine which "shares" an SV when there is no sharing module present. Or "locks" it. Or
"unlocks" it. In other words, ignores its single SV argument. Exists to avoid test for a NULL
function pointer and because it could potentially warn under some level of strict-ness.
void sv_nosharing(SV *sv)
upg_version
In-place upgrade of the supplied SV to a version object.
SV *sv = upg_version(SV *sv, bool qv);
Returns a pointer to the upgraded SV. Set the boolean qv if you want to force this SV to be
interpreted as an "extended" version.
SV* upg_version(SV *ver, bool qv)
vcmp Version object aware cmp. Both operands must already have been converted into version objects.
int vcmp(SV *lhv, SV *rhv)
vmess "pat" and "args" are a sprintf-style format pattern and encapsulated argument list. These are
used to generate a string message. If the message does not end with a newline, then it will be
extended with some indication of the current location in the code, as described for "mess_sv".
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)
vnormal Accepts a version object and returns the normalized string representation. Call like:
sv = vnormal(rv);
NOTE: you can pass either the object directly or the SV contained within the RV.
The SV returned has a refcount of 1.
SV* vnormal(SV *vs)
vnumify Accepts a version object and returns the normalized floating point representation. Call like:
sv = vnumify(rv);
NOTE: you can pass either the object directly or the SV contained within the RV.
The SV returned has a refcount of 1.
SV* vnumify(SV *vs)
vstringify
In order to maintain maximum compatibility with earlier versions of Perl, this function will
return either the floating point notation or the multiple dotted notation, depending on whether
the original version contained 1 or more dots, respectively.
The SV returned has a refcount of 1.
SV* vstringify(SV *vs)
vverify Validates that the SV contains valid internal structure for a version object. It may be passed
either the version object (RV) or the hash itself (HV). If the structure is valid, it returns
the HV. If the structure is invalid, it returns NULL.
SV *hv = vverify(sv);
Note that it only confirms the bare minimum structure (so as not to get confused by derived
classes which may contain additional hash entries):
SV* vverify(SV *vs)
MRO Functions
mro_get_linear_isa
Returns the mro linearisation for the given stash. By default, this will be whatever
"mro_get_linear_isa_dfs" returns unless some other MRO is in effect for the stash. The return
value is a read-only AV*.
You are responsible for "SvREFCNT_inc()" on the return value if you plan to store it anywhere
semi-permanently (otherwise it might be deleted out from under you the next time the cache is
invalidated).
AV* mro_get_linear_isa(HV* stash)
mro_method_changed_in
Invalidates method caching on any child classes of the given stash, so that they might notice the
changes in this one.
Ideally, all instances of "PL_sub_generation++" in perl source outside of mro.c should be
replaced by calls to this.
Perl automatically handles most of the common ways a method might be redefined. However, there
are a few ways you could change a method in a stash without the cache code noticing, in which
case you need to call this method afterwards:
1) Directly manipulating the stash HV entries from XS code.
2) Assigning a reference to a readonly scalar constant into a stash entry in order to create a
constant subroutine (like constant.pm does).
This same method is available from pure perl via, "mro::method_changed_in(classname)".
void mro_method_changed_in(HV* stash)
mro_register
Registers a custom mro plugin. See perlmroapi for details.
void mro_register(const struct mro_alg *mro)
Multicall Functions
dMULTICALL
Declare local variables for a multicall. See "LIGHTWEIGHT CALLBACKS" in perlcall.
dMULTICALL;
MULTICALL
Make a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
MULTICALL;
POP_MULTICALL
Closing bracket for a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
POP_MULTICALL;
PUSH_MULTICALL
Opening bracket for a lightweight callback. See "LIGHTWEIGHT CALLBACKS" in perlcall.
PUSH_MULTICALL;
Numeric functions
grok_bin
converts a string representing a binary number to numeric form.
On entry start and *len give the string to scan, *flags gives conversion flags, and result should
be NULL or a pointer to an NV. The scan stops at the end of the string, or the first invalid
character. Unless "PERL_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" returns UV_MAX, sets
"PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes the value to *result (or the
value is discarded if result is NULL).
The binary number may optionally be prefixed with "0b" or "b" unless "PERL_SCAN_DISALLOW_PREFIX"
is set in *flags on entry. If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then the binary
number may use '_' characters to separate digits.
UV grok_bin(const char* start, STRLEN* len_p,
I32* flags, NV *result)
grok_hex
converts a string representing a hex number to numeric form.
On entry start and *len give the string to scan, *flags gives conversion flags, and result should
be NULL or a pointer to an NV. The scan stops at the end of the string, or the first invalid
character. Unless "PERL_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" returns UV_MAX, sets
"PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes the value to *result (or the
value is discarded if result is NULL).
The hex number may optionally be prefixed with "0x" or "x" unless "PERL_SCAN_DISALLOW_PREFIX" is
set in *flags on entry. If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then the hex number may
use '_' characters to separate digits.
UV grok_hex(const char* start, STRLEN* len_p,
I32* flags, NV *result)
grok_number
Recognise (or not) a number. The type of the number is returned (0 if unrecognised), otherwise
it is a bit-ORed combination of IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX,
IS_NUMBER_NOT_INT, IS_NUMBER_NEG, IS_NUMBER_INFINITY, IS_NUMBER_NAN (defined in perl.h).
If the value of the number can fit an in UV, it is returned in the *valuep IS_NUMBER_IN_UV will
be set to indicate that *valuep is valid, IS_NUMBER_IN_UV will never be set unless *valuep is
valid, but *valuep may have been assigned to during processing even though IS_NUMBER_IN_UV is not
set on return. If valuep is NULL, IS_NUMBER_IN_UV will be set for the same cases as when valuep
is non-NULL, but no actual assignment (or SEGV) will occur.
IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were seen (in which case
*valuep gives the true value truncated to an integer), and IS_NUMBER_NEG if the number is
negative (in which case *valuep holds the absolute value). IS_NUMBER_IN_UV is not set if e
notation was used or the number is larger than a UV.
int grok_number(const char *pv, STRLEN len,
UV *valuep)
grok_numeric_radix
Scan and skip for a numeric decimal separator (radix).
bool grok_numeric_radix(const char **sp,
const char *send)
grok_oct
converts a string representing an octal number to numeric form.
On entry start and *len give the string to scan, *flags gives conversion flags, and result should
be NULL or a pointer to an NV. The scan stops at the end of the string, or the first invalid
character. Unless "PERL_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" returns UV_MAX, sets
"PERL_SCAN_GREATER_THAN_UV_MAX" in the output flags, and writes the value to *result (or the
value is discarded if result is NULL).
If "PERL_SCAN_ALLOW_UNDERSCORES" is set in *flags then the octal number may use '_' characters to
separate digits.
UV grok_oct(const char* start, STRLEN* len_p,
I32* flags, NV *result)
Perl_signbit
Return a non-zero integer if the sign bit on an NV is set, and 0 if it is not.
If Configure detects this system has a signbit() that will work with our NVs, then we just use it
via the #define in perl.h. Otherwise, fall back on this implementation. As a first pass, this
gets everything right except -0.0. Alas, catching -0.0 is the main use for this function, so
this is not too helpful yet. Still, at least we have the scaffolding in place to support other
systems, should that prove useful.
Configure notes: This function is called 'Perl_signbit' instead of a plain 'signbit' because it
is easy to imagine a system having a signbit() function or macro that doesn't happen to work with
our particular choice of NVs. We shouldn't just re-#define signbit as Perl_signbit and expect
the standard system headers to be happy. Also, this is a no-context function (no pTHX_) because
Perl_signbit() is usually re-#defined in perl.h as a simple macro call to the system's signbit().
Users should just always call Perl_signbit().
NOTE: this function is experimental and may change or be removed without notice.
int Perl_signbit(NV f)
scan_bin
For backwards compatibility. Use "grok_bin" instead.
NV scan_bin(const char* start, STRLEN len,
STRLEN* retlen)
scan_hex
For backwards compatibility. Use "grok_hex" instead.
NV scan_hex(const char* start, STRLEN len,
STRLEN* retlen)
scan_oct
For backwards compatibility. Use "grok_oct" instead.
NV scan_oct(const char* start, STRLEN len,
STRLEN* retlen)
Optree construction
newASSIGNOP
Constructs, checks, and returns an assignment op. left and right supply the parameters of the
assignment; they are consumed by this function and become part of the constructed op tree.
If optype is "OP_ANDASSIGN", "OP_ORASSIGN", or "OP_DORASSIGN", then a suitable conditional optree
is constructed. If optype is the opcode of a binary operator, such as "OP_BIT_OR", then an op is
constructed that performs the binary operation and assigns the result to the left argument.
Either way, if optype is non-zero then flags has no effect.
If optype is zero, then a plain scalar or list assignment is constructed. Which type of
assignment it is is automatically determined. flags gives the eight bits of "op_flags", except
that "OPf_KIDS" will be set automatically, and, shifted up eight bits, the eight bits of
"op_private", except that the bit with value 1 or 2 is automatically set as required.
OP * newASSIGNOP(I32 flags, OP *left, I32 optype,
OP *right)
newBINOP
Constructs, checks, and returns an op of any binary type. type is the opcode. flags gives the
eight bits of "op_flags", except that "OPf_KIDS" will be set automatically, and, shifted up eight
bits, the eight bits of "op_private", except that the bit with value 1 or 2 is automatically set
as required. first and last supply up to two ops to be the direct children of the binary op;
they are consumed by this function and become part of the constructed op tree.
OP * newBINOP(I32 type, I32 flags, OP *first,
OP *last)
newCONDOP
Constructs, checks, and returns a conditional-expression ("cond_expr") op. flags gives the eight
bits of "op_flags", except that "OPf_KIDS" will be set automatically, and, shifted up eight bits,
the eight bits of "op_private", except that the bit with value 1 is automatically set. first
supplies the expression selecting between the two branches, and trueop and falseop supply the
branches; they are consumed by this function and become part of the constructed op tree.
OP * newCONDOP(I32 flags, OP *first, OP *trueop,
OP *falseop)
newFOROP
Constructs, checks, and returns an op tree expressing a "foreach" loop (iteration through a list
of values). This is a heavyweight loop, with structure that allows exiting the loop by "last"
and suchlike.
sv optionally supplies the variable that will be aliased to each item in turn; if null, it
defaults to $_ (either lexical or global). expr supplies the list of values to iterate over.
block supplies the main body of the loop, and cont optionally supplies a "continue" block that
operates as a second half of the body. All of these optree inputs are consumed by this function
and become part of the constructed op tree.
flags gives the eight bits of "op_flags" for the "leaveloop" op and, shifted up eight bits, the
eight bits of "op_private" for the "leaveloop" op, except that (in both cases) some bits will be
set automatically.
OP * newFOROP(I32 flags, OP *sv, OP *expr, OP *block,
OP *cont)
newGIVENOP
Constructs, checks, and returns an op tree expressing a "given" block. cond supplies the
expression that will be locally assigned to a lexical variable, and block supplies the body of
the "given" construct; they are consumed by this function and become part of the constructed op
tree. defsv_off is the pad offset of the scalar lexical variable that will be affected. If it
is 0, the global $_ will be used.
OP * newGIVENOP(OP *cond, OP *block,
PADOFFSET defsv_off)
newGVOP Constructs, checks, and returns an op of any type that involves an embedded reference to a GV.
type is the opcode. flags gives the eight bits of "op_flags". gv identifies the GV that the op
should reference; calling this function does not transfer ownership of any reference to it.
OP * newGVOP(I32 type, I32 flags, GV *gv)
newLISTOP
Constructs, checks, and returns an op of any list type. type is the opcode. flags gives the
eight bits of "op_flags", except that "OPf_KIDS" will be set automatically if required. first
and last supply up to two ops to be direct children of the list op; they are consumed by this
function and become part of the constructed op tree.
OP * newLISTOP(I32 type, I32 flags, OP *first,
OP *last)
newLOGOP
Constructs, checks, and returns a logical (flow control) op. type is the opcode. flags gives
the eight bits of "op_flags", except that "OPf_KIDS" will be set automatically, and, shifted up
eight bits, the eight bits of "op_private", except that the bit with value 1 is automatically
set. first supplies the expression controlling the flow, and other supplies the side (alternate)
chain of ops; they are consumed by this function and become part of the constructed op tree.
OP * newLOGOP(I32 type, I32 flags, OP *first,
OP *other)
newLOOPEX
Constructs, checks, and returns a loop-exiting op (such as "goto" or "last"). type is the
opcode. label supplies the parameter determining the target of the op; it is consumed by this
function and becomes part of the constructed op tree.
OP * newLOOPEX(I32 type, OP *label)
newLOOPOP
Constructs, checks, and returns an op tree expressing a loop. This is only a loop in the control
flow through the op tree; it does not have the heavyweight loop structure that allows exiting the
loop by "last" and suchlike. flags gives the eight bits of "op_flags" for the top-level op,
except that some bits will be set automatically as required. expr supplies the expression
controlling loop iteration, and block supplies the body of the loop; they are consumed by this
function and become part of the constructed op tree. debuggable is currently unused and should
always be 1.
OP * newLOOPOP(I32 flags, I32 debuggable, OP *expr,
OP *block)
newNULLLIST
Constructs, checks, and returns a new "stub" op, which represents an empty list expression.
OP * newNULLLIST()
newOP Constructs, checks, and returns an op of any base type (any type that has no extra fields). type
is the opcode. flags gives the eight bits of "op_flags", and, shifted up eight bits, the eight
bits of "op_private".
OP * newOP(I32 type, I32 flags)
newPADOP
Constructs, checks, and returns an op of any type that involves a reference to a pad element.
type is the opcode. flags gives the eight bits of "op_flags". A pad slot is automatically
allocated, and is populated with sv; this function takes ownership of one reference to it.
This function only exists if Perl has been compiled to use ithreads.
OP * newPADOP(I32 type, I32 flags, SV *sv)
newPMOP Constructs, checks, and returns an op of any pattern matching type. type is the opcode. flags
gives the eight bits of "op_flags" and, shifted up eight bits, the eight bits of "op_private".
OP * newPMOP(I32 type, I32 flags)
newPVOP Constructs, checks, and returns an op of any type that involves an embedded C-level pointer (PV).
type is the opcode. flags gives the eight bits of "op_flags". pv supplies the C-level pointer,
which must have been allocated using "PerlMemShared_malloc"; the memory will be freed when the op
is destroyed.
OP * newPVOP(I32 type, I32 flags, char *pv)
newRANGE
Constructs and returns a "range" op, with subordinate "flip" and "flop" ops. flags gives the
eight bits of "op_flags" for the "flip" op and, shifted up eight bits, the eight bits of
"op_private" for both the "flip" and "range" ops, except that the bit with value 1 is
automatically set. left and right supply the expressions controlling the endpoints of the range;
they are consumed by this function and become part of the constructed op tree.
OP * newRANGE(I32 flags, OP *left, OP *right)
newSLICEOP
Constructs, checks, and returns an "lslice" (list slice) op. flags gives the eight bits of
"op_flags", except that "OPf_KIDS" will be set automatically, and, shifted up eight bits, the
eight bits of "op_private", except that the bit with value 1 or 2 is automatically set as
required. listval and subscript supply the parameters of the slice; they are consumed by this
function and become part of the constructed op tree.
OP * newSLICEOP(I32 flags, OP *subscript,
OP *listval)
newSTATEOP
Constructs a state op (COP). The state op is normally a "nextstate" op, but will be a "dbstate"
op if debugging is enabled for currently-compiled code. The state op is populated from
"PL_curcop" (or "PL_compiling"). If label is non-null, it supplies the name of a label to attach
to the state op; this function takes ownership of the memory pointed at by label, and will free
it. flags gives the eight bits of "op_flags" for the state op.
If o is null, the state op is returned. Otherwise the state op is combined with o into a
"lineseq" list op, which is returned. o is consumed by this function and becomes part of the
returned op tree.
OP * newSTATEOP(I32 flags, char *label, OP *o)
newSVOP Constructs, checks, and returns an op of any type that involves an embedded SV. type is the
opcode. flags gives the eight bits of "op_flags". sv gives the SV to embed in the op; this
function takes ownership of one reference to it.
OP * newSVOP(I32 type, I32 flags, SV *sv)
newUNOP Constructs, checks, and returns an op of any unary type. type is the opcode. flags gives the
eight bits of "op_flags", except that "OPf_KIDS" will be set automatically if required, and,
shifted up eight bits, the eight bits of "op_private", except that the bit with value 1 is
automatically set. first supplies an optional op to be the direct child of the unary op; it is
consumed by this function and become part of the constructed op tree.
OP * newUNOP(I32 type, I32 flags, OP *first)
newWHENOP
Constructs, checks, and returns an op tree expressing a "when" block. cond supplies the test
expression, and block supplies the block that will be executed if the test evaluates to true;
they are consumed by this function and become part of the constructed op tree. cond will be
interpreted DWIMically, often as a comparison against $_, and may be null to generate a "default"
block.
OP * newWHENOP(OP *cond, OP *block)
newWHILEOP
Constructs, checks, and returns an op tree expressing a "while" loop. This is a heavyweight
loop, with structure that allows exiting the loop by "last" and suchlike.
loop is an optional preconstructed "enterloop" op to use in the loop; if it is null then a
suitable op will be constructed automatically. expr supplies the loop's controlling expression.
block supplies the main body of the loop, and cont optionally supplies a "continue" block that
operates as a second half of the body. All of these optree inputs are consumed by this function
and become part of the constructed op tree.
flags gives the eight bits of "op_flags" for the "leaveloop" op and, shifted up eight bits, the
eight bits of "op_private" for the "leaveloop" op, except that (in both cases) some bits will be
set automatically. debuggable is currently unused and should always be 1. has_my can be
supplied as true to force the loop body to be enclosed in its own scope.
OP * newWHILEOP(I32 flags, I32 debuggable,
LOOP *loop, OP *expr, OP *block,
OP *cont, I32 has_my)
Optree Manipulation Functions
ck_entersub_args_list
Performs the default fixup of the arguments part of an "entersub" op tree. This consists of
applying list context to each of the argument ops. This is the standard treatment used on a call
marked with "&", or a method call, or a call through a subroutine reference, or any other call
where the callee can't be identified at compile time, or a call where the callee has no
prototype.
OP * ck_entersub_args_list(OP *entersubop)
ck_entersub_args_proto
Performs the fixup of the arguments part of an "entersub" op tree based on a subroutine
prototype. This makes various modifications to the argument ops, from applying context up to
inserting "refgen" ops, and checking the number and syntactic types of arguments, as directed by
the prototype. This is the standard treatment used on a subroutine call, not marked with "&",
where the callee can be identified at compile time and has a prototype.
protosv supplies the subroutine prototype to be applied to the call. It may be a normal defined
scalar, of which the string value will be used. Alternatively, for convenience, it may be a
subroutine object (a "CV*" that has been cast to "SV*") which has a prototype. The prototype
supplied, in whichever form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of
arguments, a valid op tree is returned anyway. The error is reflected in the parser state,
normally resulting in a single exception at the top level of parsing which covers all the
compilation errors that occurred. In the error message, the callee is referred to by the name
defined by the namegv parameter.
OP * ck_entersub_args_proto(OP *entersubop,
GV *namegv, SV *protosv)
ck_entersub_args_proto_or_list
Performs the fixup of the arguments part of an "entersub" op tree either based on a subroutine
prototype or using default list-context processing. This is the standard treatment used on a
subroutine call, not marked with "&", where the callee can be identified at compile time.
protosv supplies the subroutine prototype to be applied to the call, or indicates that there is
no prototype. It may be a normal scalar, in which case if it is defined then the string value
will be used as a prototype, and if it is undefined then there is no prototype. Alternatively,
for convenience, it may be a subroutine object (a "CV*" that has been cast to "SV*"), of which
the prototype will be used if it has one. The prototype (or lack thereof) supplied, in whichever
form, does not need to match the actual callee referenced by the op tree.
If the argument ops disagree with the prototype, for example by having an unacceptable number of
arguments, a valid op tree is returned anyway. The error is reflected in the parser state,
normally resulting in a single exception at the top level of parsing which covers all the
compilation errors that occurred. In the error message, the callee is referred to by the name
defined by the namegv parameter.
OP * ck_entersub_args_proto_or_list(OP *entersubop,
GV *namegv,
SV *protosv)
cv_const_sv
If "cv" is a constant sub eligible for inlining. returns the constant value returned by the sub.
Otherwise, returns NULL.
Constant subs can be created with "newCONSTSUB" or as described in "Constant Functions" in
perlsub.
SV* cv_const_sv(const CV *const cv)
cv_get_call_checker
Retrieves the function that will be used to fix up a call to cv. Specifically, the function is
applied to an "entersub" op tree for a subroutine call, not marked with "&", where the callee can
be identified at compile time as cv.
The C-level function pointer is returned in *ckfun_p, and an SV argument for it is returned in
*ckobj_p. The function is intended to be called in this manner:
entersubop = (*ckfun_p)(aTHX_ entersubop, namegv, (*ckobj_p));
In this call, entersubop is a pointer to the "entersub" op, which may be replaced by the check
function, and namegv is a GV supplying the name that should be used by the check function to
refer to the callee of the "entersub" op if it needs to emit any diagnostics. It is permitted to
apply the check function in non-standard situations, such as to a call to a different subroutine
or to a method call.
By default, the function is Perl_ck_entersub_args_proto_or_list, and the SV parameter is cv
itself. This implements standard prototype processing. It can be changed, for a particular
subroutine, by "cv_set_call_checker".
void cv_get_call_checker(CV *cv,
Perl_call_checker *ckfun_p,
SV **ckobj_p)
cv_set_call_checker
Sets the function that will be used to fix up a call to cv. Specifically, the function is
applied to an "entersub" op tree for a subroutine call, not marked with "&", where the callee can
be identified at compile time as cv.
The C-level function pointer is supplied in ckfun, and an SV argument for it is supplied in
ckobj. The function is intended to be called in this manner:
entersubop = ckfun(aTHX_ entersubop, namegv, ckobj);
In this call, entersubop is a pointer to the "entersub" op, which may be replaced by the check
function, and namegv is a GV supplying the name that should be used by the check function to
refer to the callee of the "entersub" op if it needs to emit any diagnostics. It is permitted to
apply the check function in non-standard situations, such as to a call to a different subroutine
or to a method call.
The current setting for a particular CV can be retrieved by "cv_get_call_checker".
void cv_set_call_checker(CV *cv,
Perl_call_checker ckfun,
SV *ckobj)
LINKLIST
Given the root of an optree, link the tree in execution order using the "op_next" pointers and
return the first op executed. If this has already been done, it will not be redone, and
"o->op_next" will be returned. If "o->op_next" is not already set, o should be at least an
"UNOP".
OP* LINKLIST(OP *o)
newCONSTSUB
See "newCONSTSUB_flags".
CV* newCONSTSUB(HV* stash, const char* name, SV* sv)
newCONSTSUB_flags
Creates a constant sub equivalent to Perl "sub FOO () { 123 }" which is eligible for inlining at
compile-time.
Currently, the only useful value for "flags" is SVf_UTF8.
The newly created subroutine takes ownership of a reference to the passed in SV.
Passing NULL for SV creates a constant sub equivalent to "sub BAR () {}", which won't be called
if used as a destructor, but will suppress the overhead of a call to "AUTOLOAD". (This form,
however, isn't eligible for inlining at compile time.)
CV* newCONSTSUB_flags(HV* stash, const char* name,
STRLEN len, U32 flags, SV* sv)
newXS Used by "xsubpp" to hook up XSUBs as Perl subs. filename needs to be static storage, as it is
used directly as CvFILE(), without a copy being made.
op_append_elem
Append an item to the list of ops contained directly within a list-type op, returning the
lengthened list. first is the list-type op, and last is the op to append to the list. optype
specifies the intended opcode for the list. If first is not already a list of the right type, it
will be upgraded into one. If either first or last is null, the other is returned unchanged.
OP * op_append_elem(I32 optype, OP *first, OP *last)
op_append_list
Concatenate the lists of ops contained directly within two list-type ops, returning the combined
list. first and last are the list-type ops to concatenate. optype specifies the intended opcode
for the list. If either first or last is not already a list of the right type, it will be
upgraded into one. If either first or last is null, the other is returned unchanged.
OP * op_append_list(I32 optype, OP *first, OP *last)
OP_CLASS
Return the class of the provided OP: that is, which of the *OP structures it uses. For core ops
this currently gets the information out of PL_opargs, which does not always accurately reflect
the type used. For custom ops the type is returned from the registration, and it is up to the
registree to ensure it is accurate. The value returned will be one of the OA_* constants from
op.h.
U32 OP_CLASS(OP *o)
OP_DESC Return a short description of the provided OP.
const char * OP_DESC(OP *o)
op_linklist
This function is the implementation of the "LINKLIST" macro. It should not be called directly.
OP* op_linklist(OP *o)
op_lvalue
Propagate lvalue ("modifiable") context to an op and its children. type represents the context
type, roughly based on the type of op that would do the modifying, although "local()" is
represented by OP_NULL, because it has no op type of its own (it is signalled by a flag on the
lvalue op).
This function detects things that can't be modified, such as "$x+1", and generates errors for
them. For example, "$x+1 = 2" would cause it to be called with an op of type OP_ADD and a "type"
argument of OP_SASSIGN.
It also flags things that need to behave specially in an lvalue context, such as "$$x = 5" which
might have to vivify a reference in $x.
NOTE: this function is experimental and may change or be removed without notice.
OP * op_lvalue(OP *o, I32 type)
OP_NAME Return the name of the provided OP. For core ops this looks up the name from the op_type; for
custom ops from the op_ppaddr.
const char * OP_NAME(OP *o)
op_prepend_elem
Prepend an item to the list of ops contained directly within a list-type op, returning the
lengthened list. first is the op to prepend to the list, and last is the list-type op. optype
specifies the intended opcode for the list. If last is not already a list of the right type, it
will be upgraded into one. If either first or last is null, the other is returned unchanged.
OP * op_prepend_elem(I32 optype, OP *first, OP *last)
op_scope
Wraps up an op tree with some additional ops so that at runtime a dynamic scope will be created.
The original ops run in the new dynamic scope, and then, provided that they exit normally, the
scope will be unwound. The additional ops used to create and unwind the dynamic scope will
normally be an "enter"/"leave" pair, but a "scope" op may be used instead if the ops are simple
enough to not need the full dynamic scope structure.
NOTE: this function is experimental and may change or be removed without notice.
OP * op_scope(OP *o)
rv2cv_op_cv
Examines an op, which is expected to identify a subroutine at runtime, and attempts to determine
at compile time which subroutine it identifies. This is normally used during Perl compilation to
determine whether a prototype can be applied to a function call. cvop is the op being
considered, normally an "rv2cv" op. A pointer to the identified subroutine is returned, if it
could be determined statically, and a null pointer is returned if it was not possible to
determine statically.
Currently, the subroutine can be identified statically if the RV that the "rv2cv" is to operate
on is provided by a suitable "gv" or "const" op. A "gv" op is suitable if the GV's CV slot is
populated. A "const" op is suitable if the constant value must be an RV pointing to a CV.
Details of this process may change in future versions of Perl. If the "rv2cv" op has the
"OPpENTERSUB_AMPER" flag set then no attempt is made to identify the subroutine statically: this
flag is used to suppress compile-time magic on a subroutine call, forcing it to use default
runtime behaviour.
If flags has the bit "RV2CVOPCV_MARK_EARLY" set, then the handling of a GV reference is modified.
If a GV was examined and its CV slot was found to be empty, then the "gv" op has the
"OPpEARLY_CV" flag set. If the op is not optimised away, and the CV slot is later populated with
a subroutine having a prototype, that flag eventually triggers the warning "called too early to
check prototype".
If flags has the bit "RV2CVOPCV_RETURN_NAME_GV" set, then instead of returning a pointer to the
subroutine it returns a pointer to the GV giving the most appropriate name for the subroutine in
this context. Normally this is just the "CvGV" of the subroutine, but for an anonymous
("CvANON") subroutine that is referenced through a GV it will be the referencing GV. The
resulting "GV*" is cast to "CV*" to be returned. A null pointer is returned as usual if there is
no statically-determinable subroutine.
CV * rv2cv_op_cv(OP *cvop, U32 flags)
Pad Data Structures
CvPADLIST
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 don't have CvPADLIST set - dXSTARG fetches values from PL_curpad, but that is really the
callers pad (a slot of which is allocated by every entersub).
The PADLIST has a C array where pads are stored.
The 0th entry of the PADLIST is a PADNAMELIST (which is actually just an AV, but that may change)
which represents the "names" or rather the "static type information" for lexicals. The
individual elements of a PADNAMELIST are PADNAMEs (just SVs; but, again, that may change).
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 that are
SVs_PADTMP (targets/GVs/constants) end up having &PL_sv_undef "names" (see pad_alloc()).
Only my/our variable (SvPADMY/PADNAME_isOUR) slots get valid names. The rest are op
targets/GVs/constants which are statically allocated or resolved at compile time. These don't
have names by which they can be looked up from Perl code at run time through eval"" the way
my/our variables can be. Since they can't be looked up by "name" but only by their index
allocated at compile time (which is usually in PL_op->op_targ), wasting a name SV for them
doesn't make sense.
The SVs in the names AV have their PV being the name of the variable. xlow+1..xhigh inclusive in
the NV union is a range of cop_seq numbers for which the name is valid (accessed through the
macros COP_SEQ_RANGE_LOW and _HIGH). During compilation, these fields may hold the special value
PERL_PADSEQ_INTRO to indicate various stages:
COP_SEQ_RANGE_LOW _HIGH
----------------- -----
PERL_PADSEQ_INTRO 0 variable not yet introduced: { my ($x
valid-seq# PERL_PADSEQ_INTRO variable in scope: { my ($x)
valid-seq# valid-seq# compilation of scope complete: { my ($x) }
For typed lexicals name SV is SVt_PVMG and SvSTASH points at the type. For "our" lexicals, the
type is also SVt_PVMG, with the SvOURSTASH slot pointing at the stash of the associated global
(so that duplicate "our" declarations in the same package can be detected). SvUVX is sometimes
hijacked to store the generation number during compilation.
If PADNAME_OUTER (SvFAKE) is set on the name SV, then that slot in the frame AV is a REFCNT'ed
reference to a lexical from "outside". In this case, the name SV does not use xlow and xhigh to
store a cop_seq range, since it is in scope throughout. Instead xhigh 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, xlow 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.
(PADNAME_OUTER and name of '&' is not a meaningful combination currently but could become so if
"my sub foo {}" is implemented.)
Note that formats are treated as anon subs, and are cloned each time write is called (if
necessary).
The flag SVs_PADSTALE is cleared on lexicals each time the my() is executed, and set on scope
exit. This allows the 'Variable $x is not available' warning to be generated in evals, such as
{ my $x = 1; sub f { eval '$x'} } f();
For state vars, SVs_PADSTALE is overloaded to mean 'not yet initialised'.
NOTE: this function is experimental and may change or be removed without notice.
PADLIST * CvPADLIST(CV *cv)
PadARRAY
The C array of pad entries.
NOTE: this function is experimental and may change or be removed without notice.
SV ** PadARRAY(PAD pad)
PadlistARRAY
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.
NOTE: this function is experimental and may change or be removed without notice.
PAD ** PadlistARRAY(PADLIST padlist)
PadlistMAX
The index of the last pad in the padlist.
NOTE: this function is experimental and may change or be removed without notice.
SSize_t PadlistMAX(PADLIST padlist)
PadlistNAMES
The names associated with pad entries.
NOTE: this function is experimental and may change or be removed without notice.
PADNAMELIST * PadlistNAMES(PADLIST padlist)
PadlistNAMESARRAY
The C array of pad names.
NOTE: this function is experimental and may change or be removed without notice.
PADNAME ** PadlistNAMESARRAY(PADLIST padlist)
PadlistNAMESMAX
The index of the last pad name.
NOTE: this function is experimental and may change or be removed without notice.
SSize_t PadlistNAMESMAX(PADLIST padlist)
PadlistREFCNT
The reference count of the padlist. Currently this is always 1.
NOTE: this function is experimental and may change or be removed without notice.
U32 PadlistREFCNT(PADLIST padlist)
PadMAX The index of the last pad entry.
NOTE: this function is experimental and may change or be removed without notice.
SSize_t PadMAX(PAD pad)
PadnameLEN
The length of the name.
NOTE: this function is experimental and may change or be removed without notice.
STRLEN PadnameLEN(PADNAME pn)
PadnamelistARRAY
The C array of pad names.
NOTE: this function is experimental and may change or be removed without notice.
PADNAME ** PadnamelistARRAY(PADNAMELIST pnl)
PadnamelistMAX
The index of the last pad name.
NOTE: this function is experimental and may change or be removed without notice.
SSize_t PadnamelistMAX(PADNAMELIST pnl)
PadnamePV
The name stored in the pad name struct. This returns NULL for a target or GV slot.
NOTE: this function is experimental and may change or be removed without notice.
char * PadnamePV(PADNAME pn)
PadnameSV
Returns the pad name as an SV. This is currently just "pn". It will begin returning a new
mortal SV if pad names ever stop being SVs.
NOTE: this function is experimental and may change or be removed without notice.
SV * PadnameSV(PADNAME pn)
PadnameUTF8
Whether PadnamePV is in UTF8.
NOTE: this function is experimental and may change or be removed without notice.
bool PadnameUTF8(PADNAME pn)
pad_add_name_pvs
Exactly like "pad_add_name_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_add_name_pvs(const char *name, U32 flags,
HV *typestash, HV *ourstash)
pad_findmy_pvs
Exactly like "pad_findmy_pvn", but takes a literal string instead of a string/length pair.
PADOFFSET pad_findmy_pvs(const char *name, U32 flags)
pad_new Create a new padlist, updating the global variables for the currently-compiling padlist to point
to the new padlist. The following flags can be OR'ed together:
padnew_CLONE this pad is for a cloned CV
padnew_SAVE save old globals on the save stack
padnew_SAVESUB also save extra stuff for start of sub
PADLIST * pad_new(int flags)
PL_comppad
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.
PL_comppad_name
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.
PL_curpad
Points directly to the body of the "PL_comppad" array. (I.e., this is "PAD_ARRAY(PL_comppad)".)
NOTE: this function is experimental and may change or be removed without notice.
Per-Interpreter Variables
PL_modglobal
"PL_modglobal" is a general purpose, interpreter global HV for use by extensions that need to
keep information on a per-interpreter basis. In a pinch, it can also be used as a symbol table
for extensions to share data among each other. It is a good idea to use keys prefixed by the
package name of the extension that owns the data.
HV* PL_modglobal
PL_na A convenience variable which is typically used with "SvPV" 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 the "SvPV_nolen" macro.
STRLEN PL_na
PL_opfreehook
When non-"NULL", the function pointed by this variable will be called each time an OP is freed
with the corresponding OP as the argument. This allows extensions to free any extra attribute
they have locally attached to an OP. It is also assured to first fire for the parent OP and then
for its kids.
When you replace this variable, it is considered a good practice to store the possibly previously
installed hook and that you recall it inside your own.
Perl_ophook_t PL_opfreehook
PL_peepp
Pointer to the per-subroutine peephole optimiser. This is a function that gets called at the end
of compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform
fixups of some ops and to perform small-scale optimisations. The function is called once for
each subroutine that is compiled, and is passed, as sole parameter, a pointer to the op that is
the entry point to the subroutine. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping
the existing optimiser. The basic way to do this can be seen in "Compile pass 3: peephole
optimization" in perlguts. If the new code wishes to operate on ops throughout the subroutine's
structure, rather than just at the top level, it is likely to be more convenient to wrap the
"PL_rpeepp" hook.
peep_t PL_peepp
PL_rpeepp
Pointer to the recursive peephole optimiser. This is a function that gets called at the end of
compilation of a Perl subroutine (or equivalently independent piece of Perl code) to perform
fixups of some ops and to perform small-scale optimisations. The function is called once for
each chain of ops linked through their "op_next" fields; it is recursively called to handle each
side chain. It is passed, as sole parameter, a pointer to the op that is at the head of the
chain. It modifies the op tree in place.
The peephole optimiser should never be completely replaced. Rather, add code to it by wrapping
the existing optimiser. The basic way to do this can be seen in "Compile pass 3: peephole
optimization" in perlguts. If the new code wishes to operate only on ops at a subroutine's top
level, rather than throughout the structure, it is likely to be more convenient to wrap the
"PL_peepp" hook.
peep_t PL_rpeepp
PL_sv_no
This is the "false" SV. See "PL_sv_yes". Always refer to this as &PL_sv_no.
SV PL_sv_no
PL_sv_undef
This is the "undef" SV. Always refer to this as &PL_sv_undef.
SV PL_sv_undef
PL_sv_yes
This is the "true" SV. See "PL_sv_no". Always refer to this as &PL_sv_yes.
SV PL_sv_yes
REGEXP Functions
SvRX Convenience macro to get the REGEXP from a SV. This is approximately equivalent to the following
snippet:
if (SvMAGICAL(sv))
mg_get(sv);
if (SvROK(sv))
sv = MUTABLE_SV(SvRV(sv));
if (SvTYPE(sv) == SVt_REGEXP)
return (REGEXP*) sv;
NULL will be returned if a REGEXP* is not found.
REGEXP * SvRX(SV *sv)
SvRXOK Returns a boolean indicating whether the SV (or the one it references) is a REGEXP.
If you want to do something with the REGEXP* later use SvRX instead and check for NULL.
bool SvRXOK(SV* sv)
Simple Exception Handling Macros
dXCPT Set up necessary local variables for exception handling. See "Exception Handling" in perlguts.
dXCPT;
XCPT_CATCH
Introduces a catch block. See "Exception Handling" in perlguts.
XCPT_RETHROW
Rethrows a previously caught exception. See "Exception Handling" in perlguts.
XCPT_RETHROW;
XCPT_TRY_END
Ends a try block. See "Exception Handling" in perlguts.
XCPT_TRY_START
Starts a try block. See "Exception Handling" in perlguts.
Stack Manipulation Macros
dMARK Declare a stack marker variable, "mark", for the XSUB. See "MARK" and "dORIGMARK".
dMARK;
dORIGMARK
Saves the original stack mark for the XSUB. See "ORIGMARK".
dORIGMARK;
dSP Declares a local copy of perl's stack pointer for the XSUB, available via the "SP" macro. See
"SP".
dSP;
EXTEND Used to extend the argument stack for an XSUB's return values. Once used, guarantees that there
is room for at least "nitems" to be pushed onto the stack.
void EXTEND(SP, int nitems)
MARK Stack marker variable for the XSUB. See "dMARK".
mPUSHi Push an integer onto the stack. The stack must have room for this element. Does not use "TARG".
See also "PUSHi", "mXPUSHi" and "XPUSHi".
void mPUSHi(IV iv)
mPUSHn Push a double onto the stack. The stack must have room for this element. Does not use "TARG".
See also "PUSHn", "mXPUSHn" and "XPUSHn".
void mPUSHn(NV nv)
mPUSHp Push a string onto the stack. The stack must have room for this element. The "len" indicates
the length of the string. Does not use "TARG". See also "PUSHp", "mXPUSHp" and "XPUSHp".
void mPUSHp(char* str, STRLEN len)
mPUSHs Push an SV onto the stack and mortalizes the SV. The stack must have room for this element.
Does not use "TARG". See also "PUSHs" and "mXPUSHs".
void mPUSHs(SV* sv)
mPUSHu Push an unsigned integer onto the stack. The stack must have room for this element. Does not
use "TARG". See also "PUSHu", "mXPUSHu" and "XPUSHu".
void mPUSHu(UV uv)
mXPUSHi Push an integer onto the stack, extending the stack if necessary. Does not use "TARG". See also
"XPUSHi", "mPUSHi" and "PUSHi".
void mXPUSHi(IV iv)
mXPUSHn Push a double onto the stack, extending the stack if necessary. Does not use "TARG". See also
"XPUSHn", "mPUSHn" and "PUSHn".
void mXPUSHn(NV nv)
mXPUSHp Push a string onto the stack, extending the stack if necessary. The "len" indicates the length
of the string. Does not use "TARG". See also "XPUSHp", "mPUSHp" and "PUSHp".
void mXPUSHp(char* str, STRLEN len)
mXPUSHs Push an SV onto the stack, extending the stack if necessary and mortalizes the SV. Does not use
"TARG". See also "XPUSHs" and "mPUSHs".
void mXPUSHs(SV* sv)
mXPUSHu Push an unsigned integer onto the stack, extending the stack if necessary. Does not use "TARG".
See also "XPUSHu", "mPUSHu" and "PUSHu".
void mXPUSHu(UV uv)
ORIGMARK
The original stack mark for the XSUB. See "dORIGMARK".
POPi Pops an integer off the stack.
IV POPi
POPl Pops a long off the stack.
long POPl
POPn Pops a double off the stack.
NV POPn
POPp Pops a string off the stack.
char* POPp
POPpbytex
Pops a string off the stack which must consist of bytes i.e. characters < 256.
char* POPpbytex
POPpx Pops a string off the stack. Identical to POPp. There are two names for historical reasons.
char* POPpx
POPs Pops an SV off the stack.
SV* POPs
PUSHi Push an integer onto the stack. The stack must have room for this element. Handles 'set' magic.
Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mPUSHi" instead. See also "XPUSHi" and
"mXPUSHi".
void PUSHi(IV iv)
PUSHMARK
Opening bracket for arguments on a callback. See "PUTBACK" and perlcall.
void PUSHMARK(SP)
PUSHmortal
Push a new mortal SV onto the stack. The stack must have room for this element. Does not use
"TARG". See also "PUSHs", "XPUSHmortal" and "XPUSHs".
void PUSHmortal()
PUSHn Push a double onto the stack. The stack must have room for this element. Handles 'set' magic.
Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mPUSHn" instead. See also "XPUSHn" and
"mXPUSHn".
void PUSHn(NV nv)
PUSHp Push a string onto the stack. The stack must have room for this element. The "len" indicates
the length of the string. Handles 'set' magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be
called to declare it. Do not call multiple "TARG"-oriented macros to return lists from XSUB's -
see "mPUSHp" instead. See also "XPUSHp" and "mXPUSHp".
void PUSHp(char* str, STRLEN len)
PUSHs Push an SV onto the stack. The stack must have room for this element. Does not handle 'set'
magic. Does not use "TARG". See also "PUSHmortal", "XPUSHs" and "XPUSHmortal".
void PUSHs(SV* sv)
PUSHu Push an unsigned integer onto the stack. The stack must have room for this element. Handles
'set' magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call
multiple "TARG"-oriented macros to return lists from XSUB's - see "mPUSHu" instead. See also
"XPUSHu" and "mXPUSHu".
void PUSHu(UV uv)
PUTBACK Closing bracket for XSUB arguments. This is usually handled by "xsubpp". See "PUSHMARK" and
perlcall for other uses.
PUTBACK;
SP Stack pointer. This is usually handled by "xsubpp". See "dSP" and "SPAGAIN".
SPAGAIN Refetch the stack pointer. Used after a callback. See perlcall.
SPAGAIN;
XPUSHi Push an integer onto the stack, extending the stack if necessary. Handles 'set' magic. Uses
"TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mXPUSHi" instead. See also "PUSHi" and
"mPUSHi".
void XPUSHi(IV iv)
XPUSHmortal
Push a new mortal SV onto the stack, extending the stack if necessary. Does not use "TARG". See
also "XPUSHs", "PUSHmortal" and "PUSHs".
void XPUSHmortal()
XPUSHn Push a double onto the stack, extending the stack if necessary. Handles 'set' magic. Uses
"TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mXPUSHn" instead. See also "PUSHn" and
"mPUSHn".
void XPUSHn(NV nv)
XPUSHp Push a string onto the stack, extending the stack if necessary. The "len" indicates the length
of the string. Handles 'set' magic. Uses "TARG", so "dTARGET" or "dXSTARG" should be called to
declare it. Do not call multiple "TARG"-oriented macros to return lists from XSUB's - see
"mXPUSHp" instead. See also "PUSHp" and "mPUSHp".
void XPUSHp(char* str, STRLEN len)
XPUSHs Push an SV onto the stack, extending the stack if necessary. Does not handle 'set' magic. Does
not use "TARG". See also "XPUSHmortal", "PUSHs" and "PUSHmortal".
void XPUSHs(SV* sv)
XPUSHu Push an unsigned integer onto the stack, extending the stack if necessary. Handles 'set' magic.
Uses "TARG", so "dTARGET" or "dXSTARG" should be called to declare it. Do not call multiple
"TARG"-oriented macros to return lists from XSUB's - see "mXPUSHu" instead. See also "PUSHu" and
"mPUSHu".
void XPUSHu(UV uv)
XSRETURN
Return from XSUB, indicating number of items on the stack. This is usually handled by "xsubpp".
void XSRETURN(int nitems)
XSRETURN_EMPTY
Return an empty list from an XSUB immediately.
XSRETURN_EMPTY;
XSRETURN_IV
Return an integer from an XSUB immediately. Uses "XST_mIV".
void XSRETURN_IV(IV iv)
XSRETURN_NO
Return &PL_sv_no from an XSUB immediately. Uses "XST_mNO".
XSRETURN_NO;
XSRETURN_NV
Return a double from an XSUB immediately. Uses "XST_mNV".
void XSRETURN_NV(NV nv)
XSRETURN_PV
Return a copy of a string from an XSUB immediately. Uses "XST_mPV".
void XSRETURN_PV(char* str)
XSRETURN_UNDEF
Return &PL_sv_undef from an XSUB immediately. Uses "XST_mUNDEF".
XSRETURN_UNDEF;
XSRETURN_UV
Return an integer from an XSUB immediately. Uses "XST_mUV".
void XSRETURN_UV(IV uv)
XSRETURN_YES
Return &PL_sv_yes from an XSUB immediately. Uses "XST_mYES".
XSRETURN_YES;
XST_mIV Place an integer into the specified position "pos" on the stack. The value is stored in a new
mortal SV.
void XST_mIV(int pos, IV iv)
XST_mNO Place &PL_sv_no into the specified position "pos" on the stack.
void XST_mNO(int pos)
XST_mNV Place a double into the specified position "pos" on the stack. The value is stored in a new
mortal SV.
void XST_mNV(int pos, NV nv)
XST_mPV Place a copy of a string into the specified position "pos" on the stack. The value is stored in
a new mortal SV.
void XST_mPV(int pos, char* str)
XST_mUNDEF
Place &PL_sv_undef into the specified position "pos" on the stack.
void XST_mUNDEF(int pos)
XST_mYES
Place &PL_sv_yes into the specified position "pos" on the stack.
void XST_mYES(int pos)
SV Flags
svtype An enum of flags for Perl types. These are found in the file sv.h in the "svtype" enum. Test
these flags with the "SvTYPE" macro.
The types are:
SVt_NULL
SVt_BIND (unused)
SVt_IV
SVt_NV
SVt_RV
SVt_PV
SVt_PVIV
SVt_PVNV
SVt_PVMG
SVt_REGEXP
SVt_PVGV
SVt_PVLV
SVt_PVAV
SVt_PVHV
SVt_PVCV
SVt_PVFM
SVt_PVIO
These are most easily explained from the bottom up.
SVt_PVIO is for I/O objects, SVt_PVFM for formats, SVt_PVCV for subroutines, SVt_PVHV for hashes
and SVt_PVAV for arrays.
All the others are scalar types, that is, things that can be bound to a "$" variable. For these,
the internal types are mostly orthogonal to types in the Perl language.
Hence, checking "SvTYPE(sv) < SVt_PVAV" is the best way to see whether something is a scalar.
SVt_PVGV represents a typeglob. If !SvFAKE(sv), then it is a real, incoercible typeglob. If
SvFAKE(sv), then it is a scalar to which a typeglob has been assigned. Assigning to it again
will stop it from being a typeglob. SVt_PVLV represents a scalar that delegates to another
scalar behind the scenes. It is used, e.g., for the return value of "substr" and for tied hash
and array elements. It can hold any scalar value, including a typeglob. SVt_REGEXP is for
regular expressions.
SVt_PVMG represents a "normal" scalar (not a typeglob, regular expression, or delegate). Since
most scalars do not need all the internal fields of a PVMG, we save memory by allocating smaller
structs when possible. All the other types are just simpler forms of SVt_PVMG, with fewer
internal fields.
SVt_NULL can only hold undef. SVt_IV can hold undef, an integer, or a reference. (SVt_RV is an
alias for SVt_IV, which exists for backward compatibility.) SVt_NV can hold any of those or a
double. SVt_PV can only hold undef or a string. SVt_PVIV is a superset of SVt_PV and SVt_IV.
SVt_PVNV is similar. SVt_PVMG can hold anything SVt_PVNV can hold, but it can, but does not have
to, be blessed or magical.
SVt_IV Type flag for scalars. See "svtype".
SVt_NULL
Type flag for scalars. See "svtype".
SVt_NV Type flag for scalars. See "svtype".
SVt_PV Type flag for scalars. See "svtype".
SVt_PVAV
Type flag for arrays. See "svtype".
SVt_PVCV
Type flag for subroutines. See "svtype".
SVt_PVFM
Type flag for formats. See "svtype".
SVt_PVGV
Type flag for typeglobs. See "svtype".
SVt_PVHV
Type flag for hashes. See "svtype".
SVt_PVIO
Type flag for I/O objects. See "svtype".
SVt_PVIV
Type flag for scalars. See "svtype".
SVt_PVLV
Type flag for scalars. See "svtype".
SVt_PVMG
Type flag for scalars. See "svtype".
SVt_PVNV
Type flag for scalars. See "svtype".
SVt_REGEXP
Type flag for regular expressions. See "svtype".
SV Manipulation Functions
boolSV Returns a true SV if "b" is a true value, or a false SV if "b" is 0.
See also "PL_sv_yes" and "PL_sv_no".
SV * boolSV(bool b)
croak_xs_usage
A specialised variant of "croak()" for emitting the usage message for xsubs
croak_xs_usage(cv, "eee_yow");
works out the package name and subroutine name from "cv", and then calls "croak()". Hence if "cv"
is &ouch::awk, it would call "croak" as:
Perl_croak(aTHX_ "Usage: %"SVf"::%"SVf"(%s)", "ouch" "awk", "eee_yow");
void croak_xs_usage(const CV *const cv,
const char *const params)
get_sv Returns the SV of the specified Perl scalar. "flags" are passed to "gv_fetchpv". If "GV_ADD" is
set and the Perl variable does not exist then it will be created. If "flags" is zero and the
variable does not exist then NULL is returned.
NOTE: the perl_ form of this function is deprecated.
SV* get_sv(const char *name, I32 flags)
newRV_inc
Creates an RV wrapper for an SV. The reference count for the original SV is incremented.
SV* newRV_inc(SV* sv)
newSVpadname
Creates a new SV containing the pad name. This is currently identical to "newSVsv", but pad
names may cease being SVs at some point, so "newSVpadname" is preferable.
NOTE: this function is experimental and may change or be removed without notice.
SV* newSVpadname(PADNAME *pn)
newSVpvn_utf8
Creates a new SV and copies a string into it. If utf8 is true, calls "SvUTF8_on" on the new SV.
Implemented as a wrapper around "newSVpvn_flags".
SV* newSVpvn_utf8(NULLOK const char* s, STRLEN len,
U32 utf8)
SvCUR Returns the length of the string which is in the SV. See "SvLEN".
STRLEN SvCUR(SV* sv)
SvCUR_set
Set the current length of the string which is in the SV. See "SvCUR" and "SvIV_set".
void SvCUR_set(SV* sv, STRLEN len)
SvEND Returns a pointer to the spot just after the last character in the string which is in the SV,
where there is usually a trailing null (even though Perl scalars do not strictly require it).
See "SvCUR". Access the character as *(SvEND(sv)).
Warning: If "SvCUR" is equal to "SvLEN", then "SvEND" points to unallocated memory.
char* SvEND(SV* sv)
SvGAMAGIC
Returns true if the SV has get magic or overloading. If either is true then the scalar is active
data, and has the potential to return a new value every time it is accessed. Hence you must be
careful to only read it once per user logical operation and work with that returned value. If
neither is true then the scalar's value cannot change unless written to.
U32 SvGAMAGIC(SV* sv)
SvGROW Expands the character buffer in the SV so that it has room for the indicated number of bytes
(remember to reserve space for an extra trailing NUL character). Calls "sv_grow" to perform the
expansion if necessary. Returns a pointer to the character buffer. SV must be of type >= SVt_PV.
One alternative is to call "sv_grow" if you are not sure of the type of SV.
char * SvGROW(SV* sv, STRLEN len)
SvIOK Returns a U32 value indicating whether the SV contains an integer.
U32 SvIOK(SV* sv)
SvIOKp Returns a U32 value indicating whether the SV contains an integer. Checks the private setting.
Use "SvIOK" instead.
U32 SvIOKp(SV* sv)
SvIOK_notUV
Returns a boolean indicating whether the SV contains a signed integer.
bool SvIOK_notUV(SV* sv)
SvIOK_off
Unsets the IV status of an SV.
void SvIOK_off(SV* sv)
SvIOK_on
Tells an SV that it is an integer.
void SvIOK_on(SV* sv)
SvIOK_only
Tells an SV that it is an integer and disables all other OK bits.
void SvIOK_only(SV* sv)
SvIOK_only_UV
Tells an SV that it is an unsigned integer and disables all other OK bits.
void SvIOK_only_UV(SV* sv)
SvIOK_UV
Returns a boolean indicating whether the SV contains an integer that must be interpreted as
unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be
be flagged as either SvUOK or SVIOK.
bool SvIOK_UV(SV* sv)
SvIsCOW Returns a boolean 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).
bool SvIsCOW(SV* sv)
SvIsCOW_shared_hash
Returns a boolean indicating whether the SV is Copy-On-Write shared hash key scalar.
bool SvIsCOW_shared_hash(SV* sv)
SvIV Coerces the given SV to an integer and returns it. See "SvIVx" for a version which guarantees to
evaluate sv only once.
IV SvIV(SV* sv)
SvIVX Returns the raw value in the SV's IV slot, without checks or conversions. Only use when you are
sure SvIOK is true. See also "SvIV()".
IV SvIVX(SV* sv)
SvIVx Coerces the given SV to an integer and returns it. Guarantees to evaluate "sv" only once. Only
use this if "sv" is an expression with side effects, otherwise use the more efficient "SvIV".
IV SvIVx(SV* sv)
SvIV_nomg
Like "SvIV" but doesn't process magic.
IV SvIV_nomg(SV* sv)
SvIV_set
Set the value of the IV pointer in sv to val. It is possible to perform the same function of
this macro with an lvalue assignment to "SvIVX". With future Perls, however, it will be more
efficient to use "SvIV_set" instead of the lvalue assignment to "SvIVX".
void SvIV_set(SV* sv, IV val)
SvLEN Returns the size of the string buffer in the SV, not including any part attributable to "SvOOK".
See "SvCUR".
STRLEN SvLEN(SV* sv)
SvLEN_set
Set the actual length of the string which is in the SV. See "SvIV_set".
void SvLEN_set(SV* sv, STRLEN len)
SvMAGIC_set
Set the value of the MAGIC pointer in sv to val. See "SvIV_set".
void SvMAGIC_set(SV* sv, MAGIC* val)
SvNIOK Returns a U32 value indicating whether the SV contains a number, integer or double.
U32 SvNIOK(SV* sv)
SvNIOKp Returns a U32 value indicating whether the SV contains a number, integer or double. Checks the
private setting. Use "SvNIOK" instead.
U32 SvNIOKp(SV* sv)
SvNIOK_off
Unsets the NV/IV status of an SV.
void SvNIOK_off(SV* sv)
SvNOK Returns a U32 value indicating whether the SV contains a double.
U32 SvNOK(SV* sv)
SvNOKp Returns a U32 value indicating whether the SV contains a double. Checks the private setting.
Use "SvNOK" instead.
U32 SvNOKp(SV* sv)
SvNOK_off
Unsets the NV status of an SV.
void SvNOK_off(SV* sv)
SvNOK_on
Tells an SV that it is a double.
void SvNOK_on(SV* sv)
SvNOK_only
Tells an SV that it is a double and disables all other OK bits.
void SvNOK_only(SV* sv)
SvNV Coerce the given SV to a double and return it. See "SvNVx" for a version which guarantees to
evaluate sv only once.
NV SvNV(SV* sv)
SvNVX Returns the raw value in the SV's NV slot, without checks or conversions. Only use when you are
sure SvNOK is true. See also "SvNV()".
NV SvNVX(SV* sv)
SvNVx Coerces the given SV to a double and returns it. Guarantees to evaluate "sv" only once. Only
use this if "sv" is an expression with side effects, otherwise use the more efficient "SvNV".
NV SvNVx(SV* sv)
SvNV_nomg
Like "SvNV" but doesn't process magic.
NV SvNV_nomg(SV* sv)
SvNV_set
Set the value of the NV pointer in sv to val. See "SvIV_set".
void SvNV_set(SV* sv, NV val)
SvOK Returns a U32 value indicating whether the value is defined. This is only meaningful for scalars.
U32 SvOK(SV* sv)
SvOOK Returns a U32 indicating whether the pointer to the string buffer is offset. This hack is used
internally to speed up removal of characters from the beginning of a SvPV. When SvOOK is true,
then the start of the allocated string buffer is actually "SvOOK_offset()" bytes before SvPVX.
This offset used to be stored in SvIVX, but is now stored within the spare part of the buffer.
U32 SvOOK(SV* sv)
SvOOK_offset
Reads into len the offset from SvPVX back to the true start of the allocated buffer, which will
be non-zero if "sv_chop" has been used to efficiently remove characters from start of the buffer.
Implemented as a macro, which takes the address of len, which must be of type "STRLEN".
Evaluates sv more than once. Sets len to 0 if "SvOOK(sv)" is false.
void SvOOK_offset(NN SV*sv, STRLEN len)
SvPOK Returns a U32 value indicating whether the SV contains a character string.
U32 SvPOK(SV* sv)
SvPOKp Returns a U32 value indicating whether the SV contains a character string. Checks the private
setting. Use "SvPOK" instead.
U32 SvPOKp(SV* sv)
SvPOK_off
Unsets the PV status of an SV.
void SvPOK_off(SV* sv)
SvPOK_on
Tells an SV that it is a string.
void SvPOK_on(SV* sv)
SvPOK_only
Tells an SV that it is a string and disables all other OK bits. Will also turn off the UTF-8
status.
void SvPOK_only(SV* sv)
SvPOK_only_UTF8
Tells an SV that it is a string and disables all other OK bits, and leaves the UTF-8 status as it
was.
void SvPOK_only_UTF8(SV* sv)
SvPV 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 becoming "SvPOK". Handles 'get'
magic. See also "SvPVx" for a version which guarantees to evaluate sv only once.
Note that there is no guarantee that the return value of "SvPV()" is equal to "SvPVX(sv)", or
that "SvPVX(sv)" contains valid data, or that successive calls to "SvPV(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 the SvPVX field to be valid (for example, if you intend to write to it), then
see "SvPV_force"."
char* SvPV(SV* sv, STRLEN len)
SvPVbyte
Like "SvPV", but converts sv to byte representation first if necessary.
char* SvPVbyte(SV* sv, STRLEN len)
SvPVbytex
Like "SvPV", but converts sv to byte representation first if necessary. Guarantees to evaluate
sv only once; use the more efficient "SvPVbyte" otherwise.
char* SvPVbytex(SV* sv, STRLEN len)
SvPVbytex_force
Like "SvPV_force", but converts sv to byte representation first if necessary. Guarantees to
evaluate sv only once; use the more efficient "SvPVbyte_force" otherwise.
char* SvPVbytex_force(SV* sv, STRLEN len)
SvPVbyte_force
Like "SvPV_force", but converts sv to byte representation first if necessary.
char* SvPVbyte_force(SV* sv, STRLEN len)
SvPVbyte_nolen
Like "SvPV_nolen", but converts sv to byte representation first if necessary.
char* SvPVbyte_nolen(SV* sv)
SvPVutf8
Like "SvPV", but converts sv to utf8 first if necessary.
char* SvPVutf8(SV* sv, STRLEN len)
SvPVutf8x
Like "SvPV", but converts sv to utf8 first if necessary. Guarantees to evaluate sv only once;
use the more efficient "SvPVutf8" otherwise.
char* SvPVutf8x(SV* sv, STRLEN len)
SvPVutf8x_force
Like "SvPV_force", but converts sv to utf8 first if necessary. Guarantees to evaluate sv only
once; use the more efficient "SvPVutf8_force" otherwise.
char* SvPVutf8x_force(SV* sv, STRLEN len)
SvPVutf8_force
Like "SvPV_force", but converts sv to utf8 first if necessary.
char* SvPVutf8_force(SV* sv, STRLEN len)
SvPVutf8_nolen
Like "SvPV_nolen", but converts sv to utf8 first if necessary.
char* SvPVutf8_nolen(SV* sv)
SvPVX 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)
SvPVx A version of "SvPV" which guarantees to evaluate "sv" only once. Only use this if "sv" is an
expression with side effects, otherwise use the more efficient "SvPV".
char* SvPVx(SV* sv, STRLEN len)
SvPV_force
Like "SvPV" 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 the "SvPVX"
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 was "SvROK", then the referent will have its reference count
decremented, and the SV itself may be converted to an "SvPOK" scalar with a string buffer
containing a value such as "ARRAY(0x1234)".
char* SvPV_force(SV* sv, STRLEN len)
SvPV_force_nomg
Like "SvPV_force", but doesn't process get magic.
char* SvPV_force_nomg(SV* sv, STRLEN len)
SvPV_nolen
Like "SvPV" but doesn't set a length variable.
char* SvPV_nolen(SV* sv)
SvPV_nomg
Like "SvPV" but doesn't process magic.
char* SvPV_nomg(SV* sv, STRLEN len)
SvPV_nomg_nolen
Like "SvPV_nolen" but doesn't process magic.
char* SvPV_nomg_nolen(SV* sv)
SvPV_set
Set the value of the PV pointer in sv to val. See also "SvIV_set".
Beware that the existing pointer may be involved in copy-on-write or other mischief, so do
"SvOOK_off(sv)" and use "sv_force_normal" or "SvPV_force" (or check the SvIsCOW flag) first to
make sure this modification is safe.
void SvPV_set(SV* sv, char* val)
SvREFCNT
Returns the value of the object's reference count.
U32 SvREFCNT(SV* sv)
SvREFCNT_dec
Decrements the reference count of the given SV. sv may be NULL.
void SvREFCNT_dec(SV* sv)
SvREFCNT_dec_NN
Same as SvREFCNT_dec, but can only be used if you know sv is not NULL. Since we don't have to
check the NULLness, it's faster and smaller.
void SvREFCNT_dec_NN(SV* sv)
SvREFCNT_inc
Increments the reference count of the given SV, returning the SV.
All of the following SvREFCNT_inc* macros are optimized versions of SvREFCNT_inc, and can be
replaced with SvREFCNT_inc.
SV* SvREFCNT_inc(SV* sv)
SvREFCNT_inc_NN
Same as SvREFCNT_inc, but can only be used if you know sv is not NULL. Since we don't have to
check the NULLness, it's faster and smaller.
SV* SvREFCNT_inc_NN(SV* sv)
SvREFCNT_inc_simple
Same as SvREFCNT_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)
SvREFCNT_inc_simple_NN
Same as SvREFCNT_inc_simple, but can only be used if you know sv is not NULL. Since we don't
have to check the NULLness, it's faster and smaller.
SV* SvREFCNT_inc_simple_NN(SV* sv)
SvREFCNT_inc_simple_void
Same as SvREFCNT_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.
void SvREFCNT_inc_simple_void(SV* sv)
SvREFCNT_inc_simple_void_NN
Same as SvREFCNT_inc, but can only be used if you don't need the return value, and you know that
sv is not NULL. The macro doesn't need to return a meaningful value, or check for NULLness, so
it's smaller and faster.
void SvREFCNT_inc_simple_void_NN(SV* sv)
SvREFCNT_inc_void
Same as SvREFCNT_inc, but can only be used if you don't need the return value. The macro doesn't
need to return a meaningful value.
void SvREFCNT_inc_void(SV* sv)
SvREFCNT_inc_void_NN
Same as SvREFCNT_inc, but can only be used if you don't need the return value, and you know that
sv is not NULL. The macro doesn't need to return a meaningful value, or check for NULLness, so
it's smaller and faster.
void SvREFCNT_inc_void_NN(SV* sv)
SvROK Tests if the SV is an RV.
U32 SvROK(SV* sv)
SvROK_off
Unsets the RV status of an SV.
void SvROK_off(SV* sv)
SvROK_on
Tells an SV that it is an RV.
void SvROK_on(SV* sv)
SvRV Dereferences an RV to return the SV.
SV* SvRV(SV* sv)
SvRV_set
Set the value of the RV pointer in sv to val. See "SvIV_set".
void SvRV_set(SV* sv, SV* val)
SvSTASH Returns the stash of the SV.
HV* SvSTASH(SV* sv)
SvSTASH_set
Set the value of the STASH pointer in sv to val. See "SvIV_set".
void SvSTASH_set(SV* sv, HV* val)
SvTAINT Taints an SV if tainting is enabled, and if some input to the current expression is
tainted--usually a variable, but possibly also implicit inputs such as locale settings.
"SvTAINT" propagates that taintedness to the outputs of an expression in a pessimistic fashion;
i.e., without paying attention to precisely which outputs are influenced by which inputs.
void SvTAINT(SV* sv)
SvTAINTED
Checks to see if an SV is tainted. Returns TRUE if it is, FALSE if not.
bool SvTAINTED(SV* sv)
SvTAINTED_off
Untaints an SV. Be very careful with this routine, as it short-circuits some of Perl's
fundamental security features. XS module authors should not use this function unless they fully
understand all the implications of unconditionally untainting the value. Untainting should be
done in the standard perl fashion, via a carefully crafted regexp, rather than directly
untainting variables.
void SvTAINTED_off(SV* sv)
SvTAINTED_on
Marks an SV as tainted if tainting is enabled.
void SvTAINTED_on(SV* sv)
SvTRUE 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 already SvPOK, SvIOK or SvNOK
(the public, not the private flags).
bool SvTRUE(SV* sv)
SvTRUE_nomg
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.
bool SvTRUE_nomg(SV* sv)
SvTYPE Returns the type of the SV. See "svtype".
svtype SvTYPE(SV* sv)
SvUOK Returns a boolean indicating whether the SV contains an integer that must be interpreted as
unsigned. A non-negative integer whose value is within the range of both an IV and a UV may be
be flagged as either SvUOK or SVIOK.
bool SvUOK(SV* sv)
SvUPGRADE
Used to upgrade an SV to a more complex form. Uses "sv_upgrade" to perform the upgrade if
necessary. See "svtype".
void SvUPGRADE(SV* sv, svtype type)
SvUTF8 Returns a U32 value indicating the UTF-8 status of an SV. If things are set-up properly, this
indicates whether or not the SV contains UTF-8 encoded data. You should use this after a call to
SvPV() or one of its variants, in case any call to string overloading updates the internal flag.
U32 SvUTF8(SV* sv)
SvUTF8_off
Unsets the UTF-8 status of an SV (the data is not changed, just the flag). Do not use
frivolously.
void SvUTF8_off(SV *sv)
SvUTF8_on
Turn on the UTF-8 status of an SV (the data is not changed, just the flag). Do not use
frivolously.
void SvUTF8_on(SV *sv)
SvUV Coerces the given SV to an unsigned integer and returns it. See "SvUVx" for a version which
guarantees to evaluate sv only once.
UV SvUV(SV* sv)
SvUVX Returns the raw value in the SV's UV slot, without checks or conversions. Only use when you are
sure SvIOK is true. See also "SvUV()".
UV SvUVX(SV* sv)
SvUVx Coerces the given SV to an unsigned integer and returns it. Guarantees to evaluate "sv" only
once. Only use this if "sv" is an expression with side effects, otherwise use the more efficient
"SvUV".
UV SvUVx(SV* sv)
SvUV_nomg
Like "SvUV" but doesn't process magic.
UV SvUV_nomg(SV* sv)
SvUV_set
Set the value of the UV pointer in sv to val. See "SvIV_set".
void SvUV_set(SV* sv, UV val)
SvVOK Returns a boolean indicating whether the SV contains a v-string.
bool SvVOK(SV* sv)
sv_catpvn_nomg
Like "sv_catpvn" but doesn't process magic.
void sv_catpvn_nomg(SV* sv, const char* ptr,
STRLEN len)
sv_catpv_nomg
Like "sv_catpv" but doesn't process magic.
void sv_catpv_nomg(SV* sv, const char* ptr)
sv_catsv_nomg
Like "sv_catsv" but doesn't process magic.
void sv_catsv_nomg(SV* dsv, SV* ssv)
sv_derived_from
Exactly like "sv_derived_from_pv", but doesn't take a "flags" parameter.
bool sv_derived_from(SV* sv, const char *const name)
sv_derived_from_pv
Exactly like "sv_derived_from_pvn", but takes a nul-terminated string instead of a string/length
pair.
bool sv_derived_from_pv(SV* sv,
const char *const name,
U32 flags)
sv_derived_from_pvn
Returns a boolean indicating whether the SV is derived from the specified class at the C level.
To check derivation at the Perl level, call "isa()" as a normal Perl method.
Currently, the only significant value for "flags" is SVf_UTF8.
bool sv_derived_from_pvn(SV* sv,
const char *const name,
const STRLEN len, U32 flags)
sv_derived_from_sv
Exactly like "sv_derived_from_pvn", but takes the name string in the form of an SV instead of a
string/length pair.
bool sv_derived_from_sv(SV* sv, SV *namesv,
U32 flags)
sv_does Like "sv_does_pv", but doesn't take a "flags" parameter.
bool sv_does(SV* sv, const char *const name)
sv_does_pv
Like "sv_does_sv", but takes a nul-terminated string instead of an SV.
bool sv_does_pv(SV* sv, const char *const name,
U32 flags)
sv_does_pvn
Like "sv_does_sv", but takes a string/length pair instead of an SV.
bool sv_does_pvn(SV* sv, const char *const name,
const STRLEN len, U32 flags)
sv_does_sv
Returns a boolean indicating whether the SV performs a specific, named role. The SV can be a
Perl object or the name of a Perl class.
bool sv_does_sv(SV* sv, SV* namesv, U32 flags)
sv_report_used
Dump the contents of all SVs not yet freed (debugging aid).
void sv_report_used()
sv_setsv_nomg
Like "sv_setsv" but doesn't process magic.
void sv_setsv_nomg(SV* dsv, SV* ssv)
sv_utf8_upgrade_nomg
Like sv_utf8_upgrade, but doesn't do magic on "sv".
STRLEN sv_utf8_upgrade_nomg(NN SV *sv)
SV-Body Allocation
looks_like_number
Test if the content of an SV looks like a number (or is a number). "Inf" and "Infinity" are
treated as numbers (so will not issue a non-numeric warning), even if your atof() doesn't grok
them. Get-magic is ignored.
I32 looks_like_number(SV *const sv)
newRV_noinc
Creates an RV wrapper for an SV. The reference count for the original SV is not incremented.
SV* newRV_noinc(SV *const sv)
newSV Creates a new SV. A non-zero "len" parameter indicates the number of bytes of preallocated
string space the SV should have. An extra byte for a trailing NUL is also reserved. (SvPOK is
not set for the SV even if string space is allocated.) The reference count for the new SV is set
to 1.
In 5.9.3, newSV() replaces the older NEWSV() API, and drops the first parameter, x, a debug aid
which allowed callers to identify themselves. This aid has been superseded by a new build
option, PERL_MEM_LOG (see "PERL_MEM_LOG" in perlhacktips). The older API is still there for use
in XS modules supporting older perls.
SV* newSV(const STRLEN len)
newSVhek
Creates a new SV from the hash key structure. It will generate scalars that point to the shared
string table where possible. Returns a new (undefined) SV if the hek is NULL.
SV* newSVhek(const HEK *const hek)
newSViv Creates a new SV and copies an integer into it. The reference count for the SV is set to 1.
SV* newSViv(const IV i)
newSVnv Creates a new SV and copies a floating point value into it. The reference count for the SV is
set to 1.
SV* newSVnv(const NV n)
newSVpv Creates a new SV and copies a string into it. The reference count for the SV is set to 1. If
"len" is zero, Perl will compute the length using strlen(). For efficiency, consider using
"newSVpvn" instead.
SV* newSVpv(const char *const s, const STRLEN len)
newSVpvf
Creates a new SV and initializes it with the string formatted like "sprintf".
SV* newSVpvf(const char *const pat, ...)
newSVpvn
Creates a new SV and copies a buffer into it, which may contain NUL characters ("\0") and other
binary data. The reference count for the SV is set to 1. Note that if "len" is zero, Perl will
create a zero length (Perl) string. You are responsible for ensuring that the source buffer is
at least "len" bytes long. If the "buffer" argument is NULL the new SV will be undefined.
SV* newSVpvn(const char *const s, const STRLEN len)
newSVpvn_flags
Creates a new SV and copies a string into it. The reference count for the SV is set to 1. Note
that if "len" is zero, Perl will create a zero length string. You are responsible for ensuring
that the source string is at least "len" bytes long. If the "s" argument is NULL the new SV will
be undefined. Currently the only flag bits accepted are "SVf_UTF8" and "SVs_TEMP". If
"SVs_TEMP" is set, then "sv_2mortal()" is called on the result before returning. If "SVf_UTF8"
is set, "s" is considered to be in UTF-8 and the "SVf_UTF8" flag will be set on the new SV.
"newSVpvn_utf8()" is a convenience wrapper for this function, defined as
#define newSVpvn_utf8(s, len, u) \
newSVpvn_flags((s), (len), (u) ? SVf_UTF8 : 0)
SV* newSVpvn_flags(const char *const s,
const STRLEN len,
const U32 flags)
newSVpvn_share
Creates a new SV with its SvPVX_const pointing to a shared string in the string table. If the
string does not already exist in the table, it is created first. Turns on the SvIsCOW flag (or
READONLY and FAKE in 5.16 and earlier). If the "hash" parameter is non-zero, that value is used;
otherwise the hash is computed. The string's hash can later be retrieved from the SV with the
"SvSHARED_HASH()" macro. The idea here is that as the string table is used for shared hash keys
these strings will have SvPVX_const == HeKEY and hash lookup will avoid string compare.
SV* newSVpvn_share(const char* s, I32 len, U32 hash)
newSVpvs
Like "newSVpvn", but takes a literal string instead of a string/length pair.
SV* newSVpvs(const char* s)
newSVpvs_flags
Like "newSVpvn_flags", but takes a literal string instead of a string/length pair.
SV* newSVpvs_flags(const char* s, U32 flags)
newSVpvs_share
Like "newSVpvn_share", but takes a literal string instead of a string/length pair and omits the
hash parameter.
SV* newSVpvs_share(const char* s)
newSVpv_share
Like "newSVpvn_share", but takes a nul-terminated string instead of a string/length pair.
SV* newSVpv_share(const char* s, U32 hash)
newSVrv Creates a new SV for the existing RV, "rv", to point to. If "rv" is not an RV then it will be
upgraded to one. If "classname" is non-null then the new SV will be blessed in the specified
package. The new SV is returned and its reference count is 1. The reference count 1 is owned by
"rv".
SV* newSVrv(SV *const rv,
const char *const classname)
newSVsv Creates a new SV which is an exact duplicate of the original SV. (Uses "sv_setsv".)
SV* newSVsv(SV *const old)
newSVuv Creates a new SV and copies an unsigned integer into it. The reference count for the SV is set
to 1.
SV* newSVuv(const UV u)
newSV_type
Creates a new SV, of the type specified. The reference count for the new SV is set to 1.
SV* newSV_type(const svtype type)
sv_2bool
This macro is only used by sv_true() or its macro equivalent, and only if the latter's argument
is neither SvPOK, SvIOK nor SvNOK. It calls sv_2bool_flags with the SV_GMAGIC flag.
bool sv_2bool(SV *const sv)
sv_2bool_flags
This function is only used by sv_true() and friends, and only if the latter's argument is
neither SvPOK, SvIOK nor SvNOK. If the flags contain SV_GMAGIC, then it does an mg_get() first.
bool sv_2bool_flags(SV *const sv, const I32 flags)
sv_2cv Using various gambits, try to get a CV from an SV; in addition, try if possible to set *st and
*gvp to the stash and GV associated with it. The flags in "lref" are passed to gv_fetchsv.
CV* sv_2cv(SV* sv, HV **const st, GV **const gvp,
const I32 lref)
sv_2io Using various gambits, try to get an IO from an SV: the IO slot if its a GV; or the recursive
result if we're an RV; or the IO slot of the symbol named after the PV if we're a string.
'Get' magic is ignored on the sv passed in, but will be called on "SvRV(sv)" if sv is an RV.
IO* sv_2io(SV *const sv)
sv_2iv_flags
Return the integer value of an SV, doing any necessary string conversion. If flags includes
SV_GMAGIC, does an mg_get() first. Normally used via the "SvIV(sv)" and "SvIVx(sv)" macros.
IV sv_2iv_flags(SV *const sv, const I32 flags)
sv_2mortal
Marks an existing SV as mortal. The SV will be destroyed "soon", either by an explicit call to
FREETMPS, or by an implicit call at places such as statement boundaries. SvTEMP() is turned on
which means that the SV's string buffer can be "stolen" if this SV is copied. See also
"sv_newmortal" and "sv_mortalcopy".
SV* sv_2mortal(SV *const sv)
sv_2nv_flags
Return the num value of an SV, doing any necessary string or integer conversion. If flags
includes SV_GMAGIC, does an mg_get() first. Normally used via the "SvNV(sv)" and "SvNVx(sv)"
macros.
NV sv_2nv_flags(SV *const sv, const I32 flags)
sv_2pvbyte
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 the "SvPVbyte" macro.
char* sv_2pvbyte(SV *sv, STRLEN *const lp)
sv_2pvutf8
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 the "SvPVutf8" macro.
char* sv_2pvutf8(SV *sv, STRLEN *const lp)
sv_2pv_flags
Returns a pointer to the string value of an SV, and sets *lp to its length. If flags includes
SV_GMAGIC, does an mg_get() first. Coerces sv to a string if necessary. Normally invoked via
the "SvPV_flags" macro. "sv_2pv()" and "sv_2pv_nomg" usually end up here too.
char* sv_2pv_flags(SV *const sv, STRLEN *const lp,
const I32 flags)
sv_2uv_flags
Return the unsigned integer value of an SV, doing any necessary string conversion. If flags
includes SV_GMAGIC, does an mg_get() first. Normally used via the "SvUV(sv)" and "SvUVx(sv)"
macros.
UV sv_2uv_flags(SV *const sv, const I32 flags)
sv_backoff
Remove any string offset. You should normally use the "SvOOK_off" macro wrapper instead.
int sv_backoff(SV *const sv)
sv_bless
Blesses an SV into a specified package. The SV must be an RV. The package must be designated by
its stash (see "gv_stashpv()"). The reference count of the SV is unaffected.
SV* sv_bless(SV *const sv, HV *const stash)
sv_catpv
Concatenates the 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".
void sv_catpv(SV *const sv, const char* ptr)
sv_catpvf
Processes its arguments like "sprintf" and appends the formatted output to an SV. 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.
void sv_catpvf(SV *const sv, const char *const pat,
...)
sv_catpvf_mg
Like "sv_catpvf", but also handles 'set' magic.
void sv_catpvf_mg(SV *const sv,
const char *const pat, ...)
sv_catpvn
Concatenates the string onto the end of the string which is in the SV. The "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".
void sv_catpvn(SV *dsv, const char *sstr, STRLEN len)
sv_catpvn_flags
Concatenates the string onto the end of the string which is in the SV. The "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. If "flags" has the "SV_SMAGIC" bit set, will "mg_set" on "dsv" afterwards if
appropriate. "sv_catpvn" and "sv_catpvn_nomg" are implemented in terms of this function.
void sv_catpvn_flags(SV *const dstr,
const char *sstr,
const STRLEN len,
const I32 flags)
sv_catpvs
Like "sv_catpvn", but takes a literal string instead of a string/length pair.
void sv_catpvs(SV* sv, const char* s)
sv_catpvs_flags
Like "sv_catpvn_flags", but takes a literal string instead of a string/length pair.
void sv_catpvs_flags(SV* sv, const char* s,
I32 flags)
sv_catpvs_mg
Like "sv_catpvn_mg", but takes a literal string instead of a string/length pair.
void sv_catpvs_mg(SV* sv, const char* s)
sv_catpvs_nomg
Like "sv_catpvn_nomg", but takes a literal string instead of a string/length pair.
void sv_catpvs_nomg(SV* sv, const char* s)
sv_catpv_flags
Concatenates the 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. If "flags" has the "SV_SMAGIC" bit
set, will "mg_set" on the modified SV if appropriate.
void sv_catpv_flags(SV *dstr, const char *sstr,
const I32 flags)
sv_catpv_mg
Like "sv_catpv", but also handles 'set' magic.
void sv_catpv_mg(SV *const sv, const char *const ptr)
sv_catsv
Concatenates the string from SV "ssv" onto the end of the string in SV "dsv". If "ssv" is null,
does nothing; otherwise modifies only "dsv". Handles 'get' magic on both SVs, but no 'set'
magic. See "sv_catsv_mg" and "sv_catsv_nomg".
void sv_catsv(SV *dstr, SV *sstr)
sv_catsv_flags
Concatenates the string from SV "ssv" onto the end of the string in SV "dsv". If "ssv" is null,
does nothing; otherwise modifies only "dsv". If "flags" include "SV_GMAGIC" bit set, will call
"mg_get" on both SVs if appropriate. If "flags" include "SV_SMAGIC", "mg_set" will be called on
the modified SV afterward, if appropriate. "sv_catsv", "sv_catsv_nomg", and "sv_catsv_mg" are
implemented in terms of this function.
void sv_catsv_flags(SV *const dsv, SV *const ssv,
const I32 flags)
sv_chop Efficient removal of characters from the beginning of the string buffer. SvPOK(sv), or at least
SvPOKp(sv), must be true and the "ptr" must be a pointer to somewhere inside the string buffer.
The "ptr" becomes the first character of the adjusted string. Uses the "OOK hack". On return,
only SvPOK(sv) and SvPOKp(sv) among the OK flags will be true.
Beware: after this function returns, "ptr" and SvPVX_const(sv) may no longer refer to the same
chunk of data.
The unfortunate similarity of this function's name to that of Perl's "chop" operator is strictly
coincidental. This function works from the left; "chop" works from the right.
void sv_chop(SV *const sv, const char *const ptr)
sv_clear
Clear an SV: call any destructors, free up any memory used by the body, and free the body itself.
The SV's head is not freed, although its type is set to all 1's so that it won't inadvertently be
assumed to be live during global destruction etc. This function should only be called when
REFCNT is zero. Most of the time you'll want to call "sv_free()" (or its macro wrapper
"SvREFCNT_dec") instead.
void sv_clear(SV *const orig_sv)
sv_cmp Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in "sv1" is
less than, equal to, or greater than the string in "sv2". Is UTF-8 and 'use bytes' aware,
handles get magic, and will coerce its args to strings if necessary. See also "sv_cmp_locale".
I32 sv_cmp(SV *const sv1, SV *const sv2)
sv_cmp_flags
Compares the strings in two SVs. Returns -1, 0, or 1 indicating whether the string in "sv1" is
less than, equal to, or greater than the string in "sv2". Is UTF-8 and 'use bytes' aware and
will coerce its args to strings if necessary. If the flags include SV_GMAGIC, it handles get
magic. See also "sv_cmp_locale_flags".
I32 sv_cmp_flags(SV *const sv1, SV *const sv2,
const U32 flags)
sv_cmp_locale
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and 'use bytes' aware,
handles get magic, and will coerce its args to strings if necessary. See also "sv_cmp".
I32 sv_cmp_locale(SV *const sv1, SV *const sv2)
sv_cmp_locale_flags
Compares the strings in two SVs in a locale-aware manner. Is UTF-8 and 'use bytes' aware and
will coerce its args to strings if necessary. If the flags contain SV_GMAGIC, it handles get
magic. See also "sv_cmp_flags".
I32 sv_cmp_locale_flags(SV *const sv1,
SV *const sv2,
const U32 flags)
sv_collxfrm
This calls "sv_collxfrm_flags" with the SV_GMAGIC flag. See "sv_collxfrm_flags".
char* sv_collxfrm(SV *const sv, STRLEN *const nxp)
sv_collxfrm_flags
Add Collate Transform magic to an SV if it doesn't already have it. If the flags contain
SV_GMAGIC, it handles get-magic.
Any scalar variable may carry PERL_MAGIC_collxfrm magic that contains the scalar data of the
variable, but transformed to such a format that a normal memory comparison can be used to compare
the data according to the locale settings.
char* sv_collxfrm_flags(SV *const sv,
STRLEN *const nxp,
I32 const flags)
sv_copypv_flags
Implementation of sv_copypv and sv_copypv_nomg. Calls get magic iff flags include SV_GMAGIC.
void sv_copypv_flags(SV *const dsv, SV *const ssv,
const I32 flags)
sv_copypv_nomg
Like sv_copypv, but doesn't invoke get magic first.
void sv_copypv_nomg(SV *const dsv, SV *const ssv)
sv_dec Auto-decrement of the value in the SV, doing string to numeric conversion if necessary. Handles
'get' magic and operator overloading.
void sv_dec(SV *const sv)
sv_dec_nomg
Auto-decrement of the value in the SV, doing string to numeric conversion if necessary. Handles
operator overloading. Skips handling 'get' magic.
void sv_dec_nomg(SV *const sv)
sv_eq 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.
I32 sv_eq(SV* sv1, SV* sv2)
sv_eq_flags
Returns a boolean indicating whether the strings in the two SVs are identical. Is UTF-8 and 'use
bytes' aware and coerces its args to strings if necessary. If the flags include SV_GMAGIC, it
handles get-magic, too.
I32 sv_eq_flags(SV* sv1, SV* sv2, const U32 flags)
sv_force_normal_flags
Undo various types of fakery on an SV, where fakery means "more than" a string: if the PV is a
shared string, make a private copy; if we're a ref, stop refing; if we're a glob, downgrade to an
xpvmg; if we're a copy-on-write scalar, this is the on-write time when we do the copy, and is
also used locally; if this is a vstring, drop the vstring magic. If "SV_COW_DROP_PV" is set then
a copy-on-write scalar drops its PV buffer (if any) and becomes SvPOK_off rather than making a
copy. (Used where this scalar is about to be set to some other value.) In addition, the "flags"
parameter gets passed to "sv_unref_flags()" when unreffing. "sv_force_normal" calls this
function with flags set to 0.
void sv_force_normal_flags(SV *const sv,
const U32 flags)
sv_free Decrement an SV's reference count, and if it drops to zero, call "sv_clear" to invoke destructors
and free up any memory used by the body; finally, deallocate the SV's head itself. Normally
called via a wrapper macro "SvREFCNT_dec".
void sv_free(SV *const sv)
sv_gets Get a line from the filehandle and store it into the SV, optionally appending to the currently-
stored string. If "append" is not 0, the line is appended to the SV instead of overwriting it.
"append" should be set to the byte offset that the appended string should start at in the SV
(typically, "SvCUR(sv)" is a suitable choice).
char* sv_gets(SV *const sv, PerlIO *const fp,
I32 append)
sv_grow Expands the character buffer in the SV. If necessary, uses "sv_unref" and upgrades the SV to
"SVt_PV". Returns a pointer to the character buffer. Use the "SvGROW" wrapper instead.
char* sv_grow(SV *const sv, STRLEN newlen)
sv_inc Auto-increment of the value in the SV, doing string to numeric conversion if necessary. Handles
'get' magic and operator overloading.
void sv_inc(SV *const sv)
sv_inc_nomg
Auto-increment of the value in the SV, doing string to numeric conversion if necessary. Handles
operator overloading. Skips handling 'get' magic.
void sv_inc_nomg(SV *const sv)
sv_insert
Inserts a string at the specified offset/length within the SV. Similar to the Perl substr()
function. Handles get magic.
void sv_insert(SV *const bigstr, const STRLEN offset,
const STRLEN len,
const char *const little,
const STRLEN littlelen)
sv_insert_flags
Same as "sv_insert", but the extra "flags" are passed to the "SvPV_force_flags" that applies to
"bigstr".
void sv_insert_flags(SV *const bigstr,
const STRLEN offset,
const STRLEN len,
const char *const little,
const STRLEN littlelen,
const U32 flags)
sv_isa Returns a boolean indicating whether the SV is blessed into the specified class. This does not
check for subtypes; use "sv_derived_from" to verify an inheritance relationship.
int sv_isa(SV* sv, const char *const name)
sv_isobject
Returns a boolean indicating whether the SV is an RV pointing to a blessed object. If the SV is
not an RV, or if the object is not blessed, then this will return false.
int sv_isobject(SV* sv)
sv_len Returns the length of the string in the SV. Handles magic and type coercion and sets the UTF8
flag appropriately. See also "SvCUR", which gives raw access to the xpv_cur slot.
STRLEN sv_len(SV *const sv)
sv_len_utf8
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.
STRLEN sv_len_utf8(SV *const sv)
sv_magic
Adds magic to an SV. First upgrades "sv" to type "SVt_PVMG" if necessary, then adds a new magic
item of type "how" to the head of the magic list.
See "sv_magicext" (which "sv_magic" now calls) for a description of the handling of the "name"
and "namlen" arguments.
You need to use "sv_magicext" to add magic to SvREADONLY SVs and also to add more than one
instance of the same 'how'.
void sv_magic(SV *const sv, SV *const obj,
const int how, const char *const name,
const I32 namlen)
sv_magicext
Adds magic to an SV, upgrading it if necessary. Applies the supplied vtable and returns a
pointer to the magic added.
Note that "sv_magicext" will allow things that "sv_magic" will not. In particular, you can add
magic to SvREADONLY SVs, and add more than one instance of the same 'how'.
If "namlen" is greater than zero then a "savepvn" copy of "name" is stored, if "namlen" is zero
then "name" is stored as-is and - as another special case - if "(name && namlen == HEf_SVKEY)"
then "name" is assumed to contain an "SV*" and is stored as-is with its REFCNT incremented.
(This is now used as a subroutine by "sv_magic".)
MAGIC * sv_magicext(SV *const sv, SV *const obj,
const int how,
const MGVTBL *const vtbl,
const char *const name,
const I32 namlen)
sv_mortalcopy
Creates a new SV which is a copy of the original SV (using "sv_setsv"). The new SV is marked as
mortal. It will be destroyed "soon", either by an explicit call to FREETMPS, or by an implicit
call at places such as statement boundaries. See also "sv_newmortal" and "sv_2mortal".
SV* sv_mortalcopy(SV *const oldsv)
sv_newmortal
Creates a new null SV which is mortal. The reference count of the SV is set to 1. It will be
destroyed "soon", either by an explicit call to FREETMPS, or by an implicit call at places such
as statement boundaries. See also "sv_mortalcopy" and "sv_2mortal".
SV* sv_newmortal()
sv_newref
Increment an SV's reference count. Use the "SvREFCNT_inc()" wrapper instead.
SV* sv_newref(SV *const sv)
sv_pos_b2u
Converts the value pointed to by offsetp from a count of bytes from the start of the string, to a
count of the equivalent number of UTF-8 chars. Handles magic and type coercion.
void sv_pos_b2u(SV *const sv, I32 *const offsetp)
sv_pos_u2b
Converts the value pointed to by offsetp from a count of UTF-8 chars from the start of the
string, to a count of the equivalent number of bytes; if lenp is non-zero, it does the same to
lenp, but this time starting from the offset, rather than from the start of the string. Handles
magic and type coercion.
Use "sv_pos_u2b_flags" in preference, which correctly handles strings longer than 2Gb.
void sv_pos_u2b(SV *const sv, I32 *const offsetp,
I32 *const lenp)
sv_pos_u2b_flags
Converts the value pointed to by offsetp from a count of UTF-8 chars from the start of the
string, to a count of the equivalent number of bytes; if lenp is non-zero, it does the same to
lenp, but this time starting from the offset, rather than from the start of the string. Handles
type coercion. flags is passed to "SvPV_flags", and usually should be
"SV_GMAGIC|SV_CONST_RETURN" to handle magic.
STRLEN sv_pos_u2b_flags(SV *const sv, STRLEN uoffset,
STRLEN *const lenp, U32 flags)
sv_pvbyten_force
The backend for the "SvPVbytex_force" macro. Always use the macro instead.
char* sv_pvbyten_force(SV *const sv, STRLEN *const lp)
sv_pvn_force
Get a sensible string out of the SV somehow. A private implementation of the "SvPV_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)
sv_pvn_force_flags
Get a sensible string out of the SV somehow. If "flags" has "SV_GMAGIC" bit set, will "mg_get"
on "sv" if appropriate, else not. "sv_pvn_force" and "sv_pvn_force_nomg" are implemented in
terms of this function. You normally want to use the various wrapper macros instead: see
"SvPV_force" and "SvPV_force_nomg"
char* sv_pvn_force_flags(SV *const sv,
STRLEN *const lp,
const I32 flags)
sv_pvutf8n_force
The backend for the "SvPVutf8x_force" macro. Always use the macro instead.
char* sv_pvutf8n_force(SV *const sv, STRLEN *const lp)
sv_reftype
Returns a string describing what the SV is a reference to.
const char* sv_reftype(const SV *const sv, const int ob)
sv_replace
Make the first argument a copy of the second, then delete the original. The target SV physically
takes over ownership of the body of the source SV and inherits its flags; however, the target
keeps any magic it owns, and any magic in the source is discarded. Note that this is a rather
specialist SV copying operation; most of the time you'll want to use "sv_setsv" or one of its
many macro front-ends.
void sv_replace(SV *const sv, SV *const nsv)
sv_reset
Underlying implementation for the "reset" Perl function. Note that the perl-level function is
vaguely deprecated.
void sv_reset(const char* s, HV *const stash)
sv_rvweaken
Weaken a reference: set the "SvWEAKREF" flag on this RV; give the referred-to SV
"PERL_MAGIC_backref" magic if it hasn't already; and push a back-reference to this RV onto the
array of backreferences associated with that magic. If the RV is magical, set magic will be
called after the RV is cleared.
SV* sv_rvweaken(SV *const sv)
sv_setiv
Copies an integer into the given SV, upgrading first if necessary. Does not handle 'set' magic.
See also "sv_setiv_mg".
void sv_setiv(SV *const sv, const IV num)
sv_setiv_mg
Like "sv_setiv", but also handles 'set' magic.
void sv_setiv_mg(SV *const sv, const IV i)
sv_setnv
Copies a double into the given SV, upgrading first if necessary. Does not handle 'set' magic.
See also "sv_setnv_mg".
void sv_setnv(SV *const sv, const NV num)
sv_setnv_mg
Like "sv_setnv", but also handles 'set' magic.
void sv_setnv_mg(SV *const sv, const NV num)
sv_setpv
Copies a string into an SV. The string must be null-terminated. Does not handle 'set' magic.
See "sv_setpv_mg".
void sv_setpv(SV *const sv, const char *const ptr)
sv_setpvf
Works like "sv_catpvf" but copies the text into the SV instead of appending it. Does not handle
'set' magic. See "sv_setpvf_mg".
void sv_setpvf(SV *const sv, const char *const pat,
...)
sv_setpvf_mg
Like "sv_setpvf", but also handles 'set' magic.
void sv_setpvf_mg(SV *const sv,
const char *const pat, ...)
sv_setpviv
Copies an integer into the given SV, also updating its string value. Does not handle 'set'
magic. See "sv_setpviv_mg".
void sv_setpviv(SV *const sv, const IV num)
sv_setpviv_mg
Like "sv_setpviv", but also handles 'set' magic.
void sv_setpviv_mg(SV *const sv, const IV iv)
sv_setpvn
Copies a string into an SV. The "len" parameter indicates the number of bytes to be copied. If
the "ptr" argument is NULL the SV will become undefined. Does not handle 'set' magic. See
"sv_setpvn_mg".
void sv_setpvn(SV *const sv, const char *const ptr,
const STRLEN len)
sv_setpvn_mg
Like "sv_setpvn", but also handles 'set' magic.
void sv_setpvn_mg(SV *const sv,
const char *const ptr,
const STRLEN len)
sv_setpvs
Like "sv_setpvn", but takes a literal string instead of a string/length pair.
void sv_setpvs(SV* sv, const char* s)
sv_setpvs_mg
Like "sv_setpvn_mg", but takes a literal string instead of a string/length pair.
void sv_setpvs_mg(SV* sv, const char* s)
sv_setpv_mg
Like "sv_setpv", but also handles 'set' magic.
void sv_setpv_mg(SV *const sv, const char *const ptr)
sv_setref_iv
Copies an integer into a new SV, optionally blessing the SV. The "rv" argument will be upgraded
to an RV. That RV will be modified to point to the new SV. The "classname" argument indicates
the package for the blessing. Set "classname" to "NULL" to avoid the blessing. The new SV will
have a reference count of 1, and the RV will be returned.
SV* sv_setref_iv(SV *const rv,
const char *const classname,
const IV iv)
sv_setref_nv
Copies a double into a new SV, optionally blessing the SV. The "rv" argument will be upgraded to
an RV. That RV will be modified to point to the new SV. The "classname" argument indicates the
package for the blessing. Set "classname" to "NULL" to avoid the blessing. The new SV will have
a reference count of 1, and the RV will be returned.
SV* sv_setref_nv(SV *const rv,
const char *const classname,
const NV nv)
sv_setref_pv
Copies a pointer into a new SV, optionally blessing the SV. The "rv" argument will be upgraded
to an RV. That RV will be modified to point to the new SV. If the "pv" argument is NULL then
"PL_sv_undef" will be placed into the SV. The "classname" argument indicates the package for the
blessing. Set "classname" to "NULL" to avoid the blessing. The new SV will have a reference
count of 1, and the RV will be returned.
Do not use with other Perl types such as HV, AV, SV, CV, because those objects will become
corrupted by the pointer copy process.
Note that "sv_setref_pvn" copies the string while this copies the pointer.
SV* sv_setref_pv(SV *const rv,
const char *const classname,
void *const pv)
sv_setref_pvn
Copies a string into a new SV, optionally blessing the SV. The length of the string must be
specified with "n". The "rv" argument will be upgraded to an RV. That RV will be modified to
point to the new SV. The "classname" argument indicates the package for the blessing. Set
"classname" to "NULL" to avoid the blessing. The new SV will have a reference count of 1, and
the RV will be returned.
Note that "sv_setref_pv" copies the pointer while this copies the string.
SV* sv_setref_pvn(SV *const rv,
const char *const classname,
const char *const pv,
const STRLEN n)
sv_setref_pvs
Like "sv_setref_pvn", but takes a literal string instead of a string/length pair.
SV * sv_setref_pvs(const char* s)
sv_setref_uv
Copies an unsigned integer into a new SV, optionally blessing the SV. The "rv" argument will be
upgraded to an RV. That RV will be modified to point to the new SV. The "classname" argument
indicates the package for the blessing. Set "classname" to "NULL" to avoid the blessing. The
new SV will have a reference count of 1, and the RV will be returned.
SV* sv_setref_uv(SV *const rv,
const char *const classname,
const UV uv)
sv_setsv
Copies the contents of the source SV "ssv" into the destination SV "dsv". 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.
You probably want to use one of the assortment of wrappers, such as "SvSetSV", "SvSetSV_nosteal",
"SvSetMagicSV" and "SvSetMagicSV_nosteal".
void sv_setsv(SV *dstr, SV *sstr)
sv_setsv_flags
Copies the contents of the source SV "ssv" into the destination SV "dsv". 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 the "flags" parameter has the "SV_GMAGIC" bit set, will "mg_get"
on "ssv" if appropriate, else not. If the "flags" parameter has the "NOSTEAL" bit set then the
buffers of temps will not be stolen. <sv_setsv> and "sv_setsv_nomg" are implemented in terms of
this function.
You probably want to use one of the assortment of wrappers, such as "SvSetSV", "SvSetSV_nosteal",
"SvSetMagicSV" and "SvSetMagicSV_nosteal".
This is the primary function for copying scalars, and most other copy-ish functions and macros
use this underneath.
void sv_setsv_flags(SV *dstr, SV *sstr,
const I32 flags)
sv_setsv_mg
Like "sv_setsv", but also handles 'set' magic.
void sv_setsv_mg(SV *const dstr, SV *const sstr)
sv_setuv
Copies an unsigned integer into the given SV, upgrading first if necessary. Does not handle
'set' magic. See also "sv_setuv_mg".
void sv_setuv(SV *const sv, const UV num)
sv_setuv_mg
Like "sv_setuv", but also handles 'set' magic.
void sv_setuv_mg(SV *const sv, const UV u)
sv_tainted
Test an SV for taintedness. Use "SvTAINTED" instead.
bool sv_tainted(SV *const sv)
sv_true Returns true if the SV has a true value by Perl's rules. Use the "SvTRUE" macro instead, which
may call "sv_true()" or may instead use an in-line version.
I32 sv_true(SV *const sv)
sv_unmagic
Removes all magic of type "type" from an SV.
int sv_unmagic(SV *const sv, const int type)
sv_unmagicext
Removes all magic of type "type" with the specified "vtbl" from an SV.
int sv_unmagicext(SV *const sv, const int type,
MGVTBL *vtbl)
sv_unref_flags
Unsets the RV status of the SV, and decrements the reference count of whatever was being
referenced by the RV. This can almost be thought of as a reversal of "newSVrv". The "cflags"
argument can contain "SV_IMMEDIATE_UNREF" to force the reference count to be decremented
(otherwise the decrementing is conditional on the reference count being different from one or the
reference being a readonly SV). See "SvROK_off".
void sv_unref_flags(SV *const ref, const U32 flags)
sv_untaint
Untaint an SV. Use "SvTAINTED_off" instead.
void sv_untaint(SV *const sv)
sv_upgrade
Upgrade an SV to a more complex form. Generally adds a new body type to the SV, then copies
across as much information as possible from the old body. It croaks if the SV is already in a
more complex form than requested. You generally want to use the "SvUPGRADE" macro wrapper, which
checks the type before calling "sv_upgrade", and hence does not croak. See also "svtype".
void sv_upgrade(SV *const sv, svtype new_type)
sv_usepvn_flags
Tells an SV to use "ptr" to find its string value. Normally the string is stored inside the SV
but sv_usepvn allows the SV to use an outside string. The "ptr" should point to memory that was
allocated by "malloc". It must be the start of a mallocked block of memory, and not a pointer to
the middle of it. The string length, "len", must be supplied. By default this function will
realloc (i.e. move) the memory pointed to by "ptr", so that pointer should not be freed or used
by the programmer after giving it to sv_usepvn, and neither should any pointers from "behind"
that pointer (e.g. ptr + 1) be used.
If "flags" & SV_SMAGIC is true, will call SvSETMAGIC. If "flags" & SV_HAS_TRAILING_NUL is true,
then "ptr[len]" must be NUL, and the realloc will be skipped (i.e. the buffer is actually at
least 1 byte longer than "len", and already meets the requirements for storing in "SvPVX").
void sv_usepvn_flags(SV *const sv, char* ptr,
const STRLEN len,
const U32 flags)
sv_utf8_decode
If the PV of the SV is an octet sequence in UTF-8 and contains a multiple-byte character, the
"SvUTF8" flag is turned on so that it looks like a character. If the PV contains only single-
byte characters, the "SvUTF8" flag stays off. Scans PV for validity and returns false if the PV
is invalid UTF-8.
NOTE: this function is experimental and may change or be removed without notice.
bool sv_utf8_decode(SV *const sv)
sv_utf8_downgrade
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, if
"fail_ok" is not true, croaks.
This is not a general purpose Unicode to byte encoding interface: use the Encode extension for
that.
NOTE: this function is experimental and may change or be removed without notice.
bool sv_utf8_downgrade(SV *const sv,
const bool fail_ok)
sv_utf8_encode
Converts the PV of an SV to UTF-8, but then turns the "SvUTF8" flag off so that it looks like
octets again.
void sv_utf8_encode(SV *const sv)
sv_utf8_upgrade
Converts the PV of an SV to its UTF-8-encoded form. Forces the SV to string form if it is not
already. Will "mg_get" on "sv" if appropriate. Always sets the SvUTF8 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.
STRLEN sv_utf8_upgrade(SV *sv)
sv_utf8_upgrade_flags
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. If "flags" has "SV_GMAGIC" bit set, will "mg_get" on "sv" if appropriate,
else not. Returns the number of bytes in the converted string "sv_utf8_upgrade" and
"sv_utf8_upgrade_nomg" are implemented in terms of this function.
This is not a general purpose byte encoding to Unicode interface: use the Encode extension for
that.
STRLEN sv_utf8_upgrade_flags(SV *const sv,
const I32 flags)
sv_utf8_upgrade_nomg
Like sv_utf8_upgrade, but doesn't do magic on "sv".
STRLEN sv_utf8_upgrade_nomg(SV *sv)
sv_vcatpvf
Processes its arguments like "vsprintf" and appends the formatted output to an SV. Does not
handle 'set' magic. See "sv_vcatpvf_mg".
Usually used via its frontend "sv_catpvf".
void sv_vcatpvf(SV *const sv, const char *const pat,
va_list *const args)
sv_vcatpvfn
void sv_vcatpvfn(SV *const sv, const char *const pat,
const STRLEN patlen,
va_list *const args,
SV **const svargs, const I32 svmax,
bool *const maybe_tainted)
sv_vcatpvfn_flags
Processes its arguments like "vsprintf" and appends the formatted output to an SV. Uses an array
of SVs if the C style variable argument list is missing (NULL). When running with taint checks
enabled, indicates via "maybe_tainted" if results are untrustworthy (often due to the use of
locales).
If called as "sv_vcatpvfn" or flags include "SV_GMAGIC", calls get magic.
Usually used via one of its frontends "sv_vcatpvf" and "sv_vcatpvf_mg".
void sv_vcatpvfn_flags(SV *const sv,
const char *const pat,
const STRLEN patlen,
va_list *const args,
SV **const svargs,
const I32 svmax,
bool *const maybe_tainted,
const U32 flags)
sv_vcatpvf_mg
Like "sv_vcatpvf", but also handles 'set' magic.
Usually used via its frontend "sv_catpvf_mg".
void sv_vcatpvf_mg(SV *const sv,
const char *const pat,
va_list *const args)
sv_vsetpvf
Works like "sv_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 frontend "sv_setpvf".
void sv_vsetpvf(SV *const sv, const char *const pat,
va_list *const args)
sv_vsetpvfn
Works like "sv_vcatpvfn" but copies the text into the SV instead of appending it.
Usually used via one of its frontends "sv_vsetpvf" and "sv_vsetpvf_mg".
void sv_vsetpvfn(SV *const sv, const char *const pat,
const STRLEN patlen,
va_list *const args,
SV **const svargs, const I32 svmax,
bool *const maybe_tainted)
sv_vsetpvf_mg
Like "sv_vsetpvf", but also handles 'set' magic.
Usually used via its frontend "sv_setpvf_mg".
void sv_vsetpvf_mg(SV *const sv,
const char *const pat,
va_list *const args)
Unicode Support
bytes_cmp_utf8
Compares the sequence of characters (stored as octets) in "b", "blen" with the sequence of
characters (stored as UTF-8) in "u", "ulen". Returns 0 if they are equal, -1 or -2 if the first
string is less than the second string, +1 or +2 if the first string is greater than the second
string.
-1 or +1 is returned if the shorter string was identical to the start of the longer string. -2 or
+2 is returned if the was a difference between characters within the strings.
int bytes_cmp_utf8(const U8 *b, STRLEN blen,
const U8 *u, STRLEN ulen)
bytes_from_utf8
Converts a string "s" of length "len" from UTF-8 into native byte encoding. Unlike
"utf8_to_bytes" but like "bytes_to_utf8", returns a pointer to the newly-created string, and
updates "len" to contain the new length. Returns the original string if no conversion occurs,
"len" is unchanged. Do nothing if "is_utf8" points to 0. Sets "is_utf8" to 0 if "s" is converted
or consisted entirely of characters that are invariant in utf8 (i.e., US-ASCII on non-EBCDIC
machines).
NOTE: this function is experimental and may change or be removed without notice.
U8* bytes_from_utf8(const U8 *s, STRLEN *len,
bool *is_utf8)
bytes_to_utf8
Converts a string "s" of length "len" bytes from the native encoding into UTF-8. Returns a
pointer to the newly-created string, and sets "len" to reflect the new length in bytes.
A NUL character will be written after the end of the string.
If you want to convert to UTF-8 from encodings other than the native (Latin1 or EBCDIC), see
"sv_recode_to_utf8"().
NOTE: this function is experimental and may change or be removed without notice.
U8* bytes_to_utf8(const U8 *s, STRLEN *len)
foldEQ_utf8
Returns true if the leading portions of the strings "s1" and "s2" (either or both of which may be
in UTF-8) are the same case-insensitively; false otherwise. How far into the strings to compare
is determined by other input parameters.
If "u1" is true, the string "s1" is assumed to be in UTF-8-encoded Unicode; otherwise it is
assumed to be in native 8-bit encoding. Correspondingly for "u2" with respect to "s2".
If the byte length "l1" is non-zero, it says how far into "s1" to check for fold equality. In
other words, "s1"+"l1" will be used as a goal to reach. The scan will not be considered to be a
match unless the goal is reached, and scanning won't continue past that goal. Correspondingly
for "l2" with respect to "s2".
If "pe1" is non-NULL and the pointer it points to is not NULL, that pointer is considered an end
pointer to the position 1 byte past the maximum point in "s1" beyond which scanning will not
continue under any circumstances. (This routine assumes that UTF-8 encoded input strings are not
malformed; malformed input can cause it to read past "pe1"). This means that if both "l1" and
"pe1" are specified, and "pe1" is less than "s1"+"l1", the match will never be successful because
it can never get as far as its goal (and in fact is asserted against). Correspondingly for "pe2"
with respect to "s2".
At least one of "s1" and "s2" must have a goal (at least one of "l1" and "l2" must be non-zero),
and if both do, both have to be reached for a successful match. Also, if the fold of a
character is multiple characters, all of them must be matched (see tr21 reference below for
'folding').
Upon a successful match, if "pe1" is non-NULL, it will be set to point to the beginning of the
next character of "s1" beyond what was matched. Correspondingly for "pe2" and "s2".
For case-insensitiveness, the "casefolding" of Unicode is used instead of upper/lowercasing both
the characters, see <http://www.unicode.org/unicode/reports/tr21/> (Case Mappings).
I32 foldEQ_utf8(const char *s1, char **pe1, UV l1,
bool u1, const char *s2, char **pe2,
UV l2, bool u2)
is_ascii_string
Returns true if the first "len" bytes of the string "s" are the same whether or not the string is
encoded in UTF-8 (or UTF-EBCDIC on EBCDIC machines). That is, if they are invariant. On ASCII-
ish machines, only ASCII characters fit this definition, hence the function's name.
If "len" is 0, it will be calculated using strlen(s).
See also "is_utf8_string"(), "is_utf8_string_loclen"(), and "is_utf8_string_loc"().
bool is_ascii_string(const U8 *s, STRLEN len)
is_utf8_char
DEPRECATED!
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 "is_utf8_char_buf" instead.
STRLEN is_utf8_char(const U8 *s)
is_utf8_char_buf
Returns the number of bytes that comprise the first UTF-8 encoded character in buffer "buf".
"buf_end" should point to one position beyond the end of the buffer. 0 is returned if "buf" does
not point to a complete, valid UTF-8 encoded character.
Note that an INVARIANT character (i.e. ASCII on non-EBCDIC machines) is a valid UTF-8 character.
STRLEN is_utf8_char_buf(const U8 *buf,
const U8 *buf_end)
is_utf8_string
Returns true if the first "len" bytes of string "s" form a valid UTF-8 string, false otherwise.
If "len" is 0, it will be calculated using strlen(s) (which means if you use this option, that
"s" has to have a terminating NUL byte). Note that all characters being ASCII constitute 'a
valid UTF-8 string'.
See also "is_ascii_string"(), "is_utf8_string_loclen"(), and "is_utf8_string_loc"().
bool is_utf8_string(const U8 *s, STRLEN len)
is_utf8_string_loc
Like "is_utf8_string" but stores the location of the failure (in the case of "utf8ness failure")
or the location "s"+"len" (in the case of "utf8ness success") in the "ep".
See also "is_utf8_string_loclen"() and "is_utf8_string"().
bool is_utf8_string_loc(const U8 *s, STRLEN len,
const U8 **ep)
is_utf8_string_loclen
Like "is_utf8_string"() but stores the location of the failure (in the case of "utf8ness
failure") or the location "s"+"len" (in the case of "utf8ness success") in the "ep", and the
number of UTF-8 encoded characters in the "el".
See also "is_utf8_string_loc"() and "is_utf8_string"().
bool is_utf8_string_loclen(const U8 *s, STRLEN len,
const U8 **ep, STRLEN *el)
pv_uni_display
Build to the scalar "dsv" a displayable version of the string "spv", length "len", the
displayable version being at most "pvlim" bytes long (if longer, the rest is truncated and "..."
will be appended).
The "flags" argument can have UNI_DISPLAY_ISPRINT set to display isPRINT()able characters as
themselves, UNI_DISPLAY_BACKSLASH to display the \\[nrfta\\] as the backslashed versions (like
'\n') (UNI_DISPLAY_BACKSLASH is preferred over UNI_DISPLAY_ISPRINT for \\). UNI_DISPLAY_QQ (and
its alias UNI_DISPLAY_REGEX) have both UNI_DISPLAY_BACKSLASH and UNI_DISPLAY_ISPRINT turned on.
The pointer to the PV of the "dsv" is returned.
char* pv_uni_display(SV *dsv, const U8 *spv,
STRLEN len, STRLEN pvlim,
UV flags)
sv_cat_decode
The encoding is assumed to be an Encode object, the PV of the ssv is assumed to be octets in that
encoding and decoding the input starts from the position which (PV + *offset) pointed to. The
dsv will be concatenated the decoded UTF-8 string from ssv. Decoding will terminate when the
string tstr appears in decoding output or the input ends on the PV of the ssv. The value which
the offset points will be modified to the last input position on the ssv.
Returns TRUE if the terminator was found, else returns FALSE.
bool sv_cat_decode(SV* dsv, SV *encoding, SV *ssv,
int *offset, char* tstr, int tlen)
sv_recode_to_utf8
The encoding is assumed to be an Encode object, on entry the PV of the sv is assumed to be octets
in that encoding, and the sv will be converted into Unicode (and UTF-8).
If the sv already is UTF-8 (or if it is not POK), or if the encoding is not a reference, nothing
is done to the sv. If the encoding is not an "Encode::XS" Encoding object, bad things will
happen. (See lib/encoding.pm and Encode.)
The PV of the sv is returned.
char* sv_recode_to_utf8(SV* sv, SV *encoding)
sv_uni_display
Build to the scalar "dsv" a displayable version of the scalar "sv", the displayable version being
at most "pvlim" bytes long (if longer, the rest is truncated and "..." will be appended).
The "flags" argument is as in "pv_uni_display"().
The pointer to the PV of the "dsv" is returned.
char* sv_uni_display(SV *dsv, SV *ssv, STRLEN pvlim,
UV flags)
to_utf8_case
The "p" contains the pointer to the UTF-8 string encoding the character that is being converted.
This routine assumes that the character at "p" is well-formed.
The "ustrp" is a pointer to the character buffer to put the conversion result to. The "lenp" is
a pointer to the length of the result.
The "swashp" is a pointer to the swash to use.
Both the special and normal mappings are stored in lib/unicore/To/Foo.pl, and loaded by SWASHNEW,
using lib/utf8_heavy.pl. The "special" (usually, but not always, a multicharacter mapping), is
tried first.
The "special" is a string like "utf8::ToSpecLower", which means the hash %utf8::ToSpecLower. The
access to the hash is through Perl_to_utf8_case().
The "normal" is a string like "ToLower" which means the swash %utf8::ToLower.
UV to_utf8_case(const U8 *p, U8* ustrp,
STRLEN *lenp, SV **swashp,
const char *normal,
const char *special)
to_utf8_fold
Convert the UTF-8 encoded character at "p" to its foldcase version and store that in UTF-8 in
"ustrp" and its length in bytes in "lenp". Note that the "ustrp" needs to be at least
UTF8_MAXBYTES_CASE+1 bytes since the foldcase version may be longer than the original character
(up to three characters).
The first character of the foldcased version is returned (but note, as explained above, that
there may be more.)
The character at "p" is assumed by this routine to be well-formed.
UV to_utf8_fold(const U8 *p, U8* ustrp,
STRLEN *lenp)
to_utf8_lower
Convert the UTF-8 encoded character at "p" to its lowercase version and store that in UTF-8 in
ustrp and its length in bytes in "lenp". Note that the "ustrp" needs to be at least
UTF8_MAXBYTES_CASE+1 bytes since the lowercase version may be longer than the original character.
The first character of the lowercased version is returned (but note, as explained above, that
there may be more.)
The character at "p" is assumed by this routine to be well-formed.
UV to_utf8_lower(const U8 *p, U8* ustrp,
STRLEN *lenp)
to_utf8_title
Convert the UTF-8 encoded character at "p" to its titlecase version and store that in UTF-8 in
"ustrp" and its length in bytes in "lenp". Note that the "ustrp" needs to be at least
UTF8_MAXBYTES_CASE+1 bytes since the titlecase version may be longer than the original character.
The first character of the titlecased version is returned (but note, as explained above, that
there may be more.)
The character at "p" is assumed by this routine to be well-formed.
UV to_utf8_title(const U8 *p, U8* ustrp,
STRLEN *lenp)
to_utf8_upper
Convert the UTF-8 encoded character at "p" to its uppercase version and store that in UTF-8 in
"ustrp" and its length in bytes in "lenp". Note that the ustrp needs to be at least
UTF8_MAXBYTES_CASE+1 bytes since the uppercase version may be longer than the original character.
The first character of the uppercased version is returned (but note, as explained above, that
there may be more.)
The character at "p" is assumed by this routine to be well-formed.
UV to_utf8_upper(const U8 *p, U8* ustrp,
STRLEN *lenp)
utf8n_to_uvchr
Returns the native character value of the first character in the string "s" which is assumed to
be in UTF-8 encoding; "retlen" will be set to the length, in bytes, of that character.
"length" and "flags" are the same as "utf8n_to_uvuni"().
UV utf8n_to_uvchr(const U8 *s, STRLEN curlen,
STRLEN *retlen, U32 flags)
utf8n_to_uvuni
Bottom level UTF-8 decode routine. Returns the code point value of the first character in the
string "s", which is assumed to be in UTF-8 (or UTF-EBCDIC) encoding, and no longer than "curlen"
bytes; *retlen (if "retlen" isn't NULL) will be set to the length, in bytes, of that character.
The value of "flags" determines the behavior when "s" does not point to a well-formed UTF-8
character. If "flags" is 0, when a malformation is found, zero is returned and *retlen is set so
that ("s" + *retlen) is the next possible position in "s" that could begin a non-malformed
character. Also, if UTF-8 warnings haven't been lexically disabled, a warning is raised.
Various ALLOW flags can be set in "flags" to allow (and not warn on) individual types of
malformations, such as the sequence being overlong (that is, when there is a shorter sequence
that can express the same code point; overlong sequences are expressly forbidden in the UTF-8
standard due to potential security issues). Another malformation example is the first byte of a
character not being a legal first byte. See utf8.h for the list of such flags. For allowed 0
length strings, this function returns 0; for allowed overlong sequences, the computed code point
is returned; for all other allowed malformations, the Unicode REPLACEMENT CHARACTER is returned,
as these have no determinable reasonable value.
The UTF8_CHECK_ONLY flag overrides the behavior when a non-allowed (by other flags) malformation
is found. If this flag is set, the routine assumes that the caller will raise a warning, and
this function will silently just set "retlen" to "-1" (cast to "STRLEN") and return zero.
Note that this API requires disambiguation between successful decoding a NUL character, and an
error return (unless the UTF8_CHECK_ONLY flag is set), as in both cases, 0 is returned. To
disambiguate, upon a zero return, see if the first byte of "s" is 0 as well. If so, the input
was a NUL; if not, the input had an error.
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. If
"flags" contains UTF8_DISALLOW_ILLEGAL_INTERCHANGE, all three classes are treated as
malformations and handled as such. The flags UTF8_DISALLOW_SURROGATE, UTF8_DISALLOW_NONCHAR, and
UTF8_DISALLOW_SUPER (meaning above the legal Unicode maximum) can be set to disallow these
categories individually.
The flags UTF8_WARN_ILLEGAL_INTERCHANGE, UTF8_WARN_SURROGATE, UTF8_WARN_NONCHAR, and
UTF8_WARN_SUPER will cause warning messages to be raised for their respective categories, but
otherwise the code points are considered valid (not malformations). To get a category to both be
treated as a malformation and raise a warning, specify both the WARN and DISALLOW flags. (But
note that warnings are not raised if lexically disabled nor if UTF8_CHECK_ONLY is also
specified.)
Very large code points (above 0x7FFF_FFFF) are considered more problematic than the others that
are above the Unicode legal maximum. There are several reasons: they requre at least 32 bits to
represent them on ASCII platforms, are not representable at all on EBCDIC platforms, and the
original UTF-8 specification never went above this number (the current 0x10FFFF limit was imposed
later). (The smaller ones, those that fit into 32 bits, are representable by a UV on ASCII
platforms, but not by an IV, which means that the number of operations that can be performed on
them is quite restricted.) The UTF-8 encoding on ASCII platforms for these large code points
begins with a byte containing 0xFE or 0xFF. The UTF8_DISALLOW_FE_FF flag will cause them to be
treated as malformations, while allowing smaller above-Unicode code points. (Of course
UTF8_DISALLOW_SUPER will treat all above-Unicode code points, including these, as malformations.)
Similarly, UTF8_WARN_FE_FF acts just like the other WARN flags, but applies just to these code
points.
All other code points corresponding to Unicode characters, including private use and those yet to
be assigned, are never considered malformed and never warn.
Most code should use "utf8_to_uvchr_buf"() rather than call this directly.
UV utf8n_to_uvuni(const U8 *s, STRLEN curlen,
STRLEN *retlen, U32 flags)
utf8_distance
Returns the number of UTF-8 characters between the UTF-8 pointers "a" and "b".
WARNING: use only if you *know* that the pointers point inside the same UTF-8 buffer.
IV utf8_distance(const U8 *a, const U8 *b)
utf8_hop
Return the UTF-8 pointer "s" displaced by "off" characters, either forward or backward.
WARNING: do not use the following unless you *know* "off" is within the UTF-8 data pointed to by
"s" *and* that on entry "s" is aligned on the first byte of character or just after the last byte
of a character.
U8* utf8_hop(const U8 *s, I32 off)
utf8_length
Return the length of the UTF-8 char encoded string "s" in characters. Stops at "e" (inclusive).
If "e < s" or if the scan would end up past "e", croaks.
STRLEN utf8_length(const U8* s, const U8 *e)
utf8_to_bytes
Converts a string "s" of length "len" from UTF-8 into native byte encoding. Unlike
"bytes_to_utf8", this over-writes the original string, and updates "len" to contain the new
length. Returns zero on failure, setting "len" to -1.
If you need a copy of the string, see "bytes_from_utf8".
NOTE: this function is experimental and may change or be removed without notice.
U8* utf8_to_bytes(U8 *s, STRLEN *len)
utf8_to_uvchr
DEPRECATED!
Returns the native code point of the first character in the string "s" which is assumed to be in
UTF-8 encoding; "retlen" will be set to the length, in bytes, of that character.
Some, but not all, UTF-8 malformations are detected, and in fact, some malformed input could
cause reading beyond the end of the input buffer, which is why this function is deprecated. Use
"utf8_to_uvchr_buf" instead.
If "s" points to one of the detected malformations, and UTF8 warnings are enabled, zero is
returned and *retlen is set (if "retlen" isn't NULL) to -1. If those warnings are off, the
computed value if well-defined (or the Unicode REPLACEMENT CHARACTER, if not) is silently
returned, and *retlen is set (if "retlen" isn't NULL) so that ("s" + *retlen) is the next
possible position in "s" that could begin a non-malformed character. See "utf8n_to_uvuni" for
details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvchr(const U8 *s, STRLEN *retlen)
utf8_to_uvchr_buf
Returns the native code point of the first character in the string "s" which is assumed to be in
UTF-8 encoding; "send" points to 1 beyond the end of "s". *retlen will be set to the length, in
bytes, of that character.
If "s" does not point to a well-formed UTF-8 character and UTF8 warnings are enabled, zero is
returned and *retlen is set (if "retlen" isn't NULL) to -1. If those warnings are off, the
computed value, if well-defined (or the Unicode REPLACEMENT CHARACTER if not), is silently
returned, and *retlen is set (if "retlen" isn't NULL) so that ("s" + *retlen) is the next
possible position in "s" that could begin a non-malformed character. See "utf8n_to_uvuni" for
details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvchr_buf(const U8 *s, const U8 *send,
STRLEN *retlen)
utf8_to_uvuni
DEPRECATED!
Returns the Unicode code point of the first character in the string "s" which is assumed to be in
UTF-8 encoding; "retlen" will be set to the length, in bytes, of that character.
This function should only be used when the returned UV is considered an index into the Unicode
semantic tables (e.g. swashes).
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_uvuni_buf" instead.
If "s" points to one of the detected malformations, and UTF8 warnings are enabled, zero is
returned and *retlen is set (if "retlen" 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 (if "retlen" isn't NULL) so that ("s" + *retlen) is the
next possible position in "s" that could begin a non-malformed character. See "utf8n_to_uvuni"
for details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvuni(const U8 *s, STRLEN *retlen)
utf8_to_uvuni_buf
Returns the Unicode code point of the first character in the string "s" which is assumed to be in
UTF-8 encoding; "send" points to 1 beyond the end of "s". "retlen" will be set to the length, in
bytes, of that character.
This function should only be used when the returned UV is considered an index into the Unicode
semantic tables (e.g. swashes).
If "s" does not point to a well-formed UTF-8 character and UTF8 warnings are enabled, zero is
returned and *retlen is set (if "retlen" isn't NULL) to -1. If those warnings are off, the
computed value if well-defined (or the Unicode REPLACEMENT CHARACTER, if not) is silently
returned, and *retlen is set (if "retlen" isn't NULL) so that ("s" + *retlen) is the next
possible position in "s" that could begin a non-malformed character. See "utf8n_to_uvuni" for
details on when the REPLACEMENT CHARACTER is returned.
UV utf8_to_uvuni_buf(const U8 *s, const U8 *send,
STRLEN *retlen)
uvchr_to_utf8
Adds the UTF-8 representation of the Native code point "uv" to the end of the string "d"; "d"
should have at least "UTF8_MAXBYTES+1" free bytes available. The return value is the pointer to
the byte after the end of the new character. In other words,
d = uvchr_to_utf8(d, uv);
is the recommended wide native character-aware way of saying
*(d++) = uv;
U8* uvchr_to_utf8(U8 *d, UV uv)
uvuni_to_utf8_flags
Adds the UTF-8 representation of the Unicode code point "uv" to the end of the string "d"; "d"
should have at least "UTF8_MAXBYTES+1" free bytes available. The return value is the pointer to
the byte after the end of the new character. In other words,
d = uvuni_to_utf8_flags(d, uv, flags);
or, in most cases,
d = uvuni_to_utf8(d, uv);
(which is equivalent to)
d = uvuni_to_utf8_flags(d, uv, 0);
This is the recommended Unicode-aware way of saying
*(d++) = uv;
where uv is a code point expressed in Latin-1 or above, not the platform's native character set.
Almost all code should instead use "uvchr_to_utf8" or "uvchr_to_utf8_flags".
This function will convert to UTF-8 (and not warn) even code points that aren't legal Unicode or
are problematic, unless "flags" contains one or more of the following flags:
If "uv" is a Unicode surrogate code point and UNICODE_WARN_SURROGATE is set, the function will
raise a warning, provided UTF8 warnings are enabled. If instead UNICODE_DISALLOW_SURROGATE is
set, the function will fail and return NULL. If both flags are set, the function will both warn
and return NULL.
The UNICODE_WARN_NONCHAR and UNICODE_DISALLOW_NONCHAR flags correspondingly affect how the
function handles a Unicode non-character. And likewise, the UNICODE_WARN_SUPER and
UNICODE_DISALLOW_SUPER flags, affect the handling of code points that are above the Unicode
maximum of 0x10FFFF. Code points above 0x7FFF_FFFF (which are even less portable) can be warned
and/or disallowed even if other above-Unicode code points are accepted by the UNICODE_WARN_FE_FF
and UNICODE_DISALLOW_FE_FF flags.
And finally, the flag UNICODE_WARN_ILLEGAL_INTERCHANGE selects all four of the above WARN flags;
and UNICODE_DISALLOW_ILLEGAL_INTERCHANGE selects all four DISALLOW flags.
U8* uvuni_to_utf8_flags(U8 *d, UV uv, UV flags)
Variables created by "xsubpp" and "xsubpp" internal functions
ax Variable which is setup by "xsubpp" to indicate the stack base offset, used by the "ST",
"XSprePUSH" and "XSRETURN" macros. The "dMARK" macro must be called prior to setup the "MARK"
variable.
I32 ax
CLASS Variable which is setup by "xsubpp" to indicate the class name for a C++ XS constructor. This is
always a "char*". See "THIS".
char* CLASS
dAX Sets up the "ax" variable. This is usually handled automatically by "xsubpp" by calling
"dXSARGS".
dAX;
dAXMARK Sets up the "ax" variable and stack marker variable "mark". This is usually handled
automatically by "xsubpp" by calling "dXSARGS".
dAXMARK;
dITEMS Sets up the "items" variable. This is usually handled automatically by "xsubpp" by calling
"dXSARGS".
dITEMS;
dUNDERBAR
Sets up any variable needed by the "UNDERBAR" macro. It used to define "padoff_du", but it is
currently a noop. However, it is strongly advised to still use it for ensuring past and future
compatibility.
dUNDERBAR;
dXSARGS Sets up stack and mark pointers for an XSUB, calling dSP and dMARK. Sets up the "ax" and "items"
variables by calling "dAX" and "dITEMS". This is usually handled automatically by "xsubpp".
dXSARGS;
dXSI32 Sets up the "ix" variable for an XSUB which has aliases. This is usually handled automatically
by "xsubpp".
dXSI32;
items Variable which is setup by "xsubpp" to indicate the number of items on the stack. See "Variable-
length Parameter Lists" in perlxs.
I32 items
ix Variable which is setup by "xsubpp" to indicate which of an XSUB's aliases was used to invoke it.
See "The ALIAS: Keyword" in perlxs.
I32 ix
newXSproto
Used by "xsubpp" to hook up XSUBs as Perl subs. Adds Perl prototypes to the subs.
RETVAL Variable which is setup by "xsubpp" to hold the return value for an XSUB. This is always the
proper type for the XSUB. See "The RETVAL Variable" in perlxs.
(whatever) RETVAL
ST Used to access elements on the XSUB's stack.
SV* ST(int ix)
THIS Variable which is setup by "xsubpp" to designate the object in a C++ XSUB. This is always the
proper type for the C++ object. See "CLASS" and "Using XS With C++" in perlxs.
(whatever) THIS
UNDERBAR
The SV* corresponding to the $_ variable. Works even if there is a lexical $_ in scope.
XS Macro to declare an XSUB and its C parameter list. This is handled by "xsubpp". It is the same
as using the more explicit XS_EXTERNAL macro.
XS_APIVERSION_BOOTCHECK
Macro to verify that the perl api version an XS module has been compiled against matches the api
version of the perl interpreter it's being loaded into.
XS_APIVERSION_BOOTCHECK;
XS_EXTERNAL
Macro to declare an XSUB and its C parameter list explicitly exporting the symbols.
XS_INTERNAL
Macro to declare an XSUB and its C parameter list without exporting the symbols. This is handled
by "xsubpp" and generally preferable over exporting the XSUB symbols unnecessarily.
XS_VERSION
The version identifier for an XS module. This is usually handled automatically by
"ExtUtils::MakeMaker". See "XS_VERSION_BOOTCHECK".
XS_VERSION_BOOTCHECK
Macro to verify that a PM module's $VERSION variable matches the XS module's "XS_VERSION"
variable. This is usually handled automatically by "xsubpp". See "The VERSIONCHECK: Keyword" in
perlxs.
XS_VERSION_BOOTCHECK;
Warning and Dieing
croak This is an XS interface to Perl's "die" 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
enclosing "eval", but subject to modification by a $SIG{__DIE__} handler. In any case, the
"croak" function never returns normally.
For historical reasons, if "pat" is null then the contents of "ERRSV" ($@) will be used as an
error message or object instead of building an error message from arguments. If you want to
throw a non-string object, or build an error message in an SV yourself, it is preferable to use
the "croak_sv" function, which does not involve clobbering "ERRSV".
void croak(const char *pat, ...)
croak_no_modify
Exactly equivalent to "Perl_croak(aTHX_ "%s", PL_no_modify)", but generates terser object code
than using "Perl_croak". Less code used on exception code paths reduces CPU cache pressure.
void croak_no_modify()
croak_sv
This is an XS interface to Perl's "die" function.
"baseex" is the error message or object. If it is a reference, it will be used as-is. Otherwise
it is used as a string, and if it does not end with a newline then it will be extended with some
indication of the current location in the code, as described for "mess_sv".
The error message or object will be used as an exception, by default returning control to the
nearest enclosing "eval", but subject to modification by a $SIG{__DIE__} handler. In any case,
the "croak_sv" function never returns normally.
To die with a simple string message, the "croak" function may be more convenient.
void croak_sv(SV *baseex)
die Behaves the same as "croak", except for the return type. It should be used only where the "OP *"
return type is required. The function never actually returns.
OP * die(const char *pat, ...)
die_sv Behaves the same as "croak_sv", except for the return type. It should be used only where the "OP
*" return type is required. The function never actually returns.
OP * die_sv(SV *baseex)
vcroak This is an XS interface to Perl's "die" function.
"pat" and "args" are a sprintf-style format pattern and encapsulated argument list. These are
used to generate a string message. If the message does not end with a newline, then it will be
extended with some indication of the current location in the code, as described for "mess_sv".
The error message will be used as an exception, by default returning control to the nearest
enclosing "eval", but subject to modification by a $SIG{__DIE__} handler. In any case, the
"croak" function never returns normally.
For historical reasons, if "pat" is null then the contents of "ERRSV" ($@) will be used as an
error message or object instead of building an error message from arguments. If you want to
throw a non-string object, or build an error message in an SV yourself, it is preferable to use
the "croak_sv" function, which does not involve clobbering "ERRSV".
void vcroak(const char *pat, va_list *args)
vwarn This is an XS interface to Perl's "warn" function.
"pat" and "args" are a sprintf-style format pattern and encapsulated argument list. These are
used to generate a string message. If the message does not end with a newline, then it will be
extended with some indication of the current location in the code, as described for "mess_sv".
The error message 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.
void vwarn(const char *pat, va_list *args)
warn This is an XS interface to Perl's "warn" 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.
void warn(const char *pat, ...)
warn_sv This is an XS interface to Perl's "warn" function.
"baseex" is the error message or object. If it is a reference, it will be used as-is. Otherwise
it is used as a string, and if it does not end with a newline then it will be extended with some
indication of the current location in the code, as described for "mess_sv".
The error message or object will by default be written to standard error, but this is subject to
modification by a $SIG{__WARN__} handler.
To warn with a simple string message, the "warn" function may be more convenient.
void warn_sv(SV *baseex)
Undocumented functions
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 use one of the undocumented functions below, you may wish to consider creating and submitting
documentation for it. If your patch is accepted, this will indicate that the interface is stable (unless
it is explicitly marked otherwise).
GetVars
Gv_AMupdate
PerlIO_clearerr
PerlIO_close
PerlIO_context_layers
PerlIO_eof
PerlIO_error
PerlIO_fileno
PerlIO_fill
PerlIO_flush
PerlIO_get_base
PerlIO_get_bufsiz
PerlIO_get_cnt
PerlIO_get_ptr
PerlIO_read
PerlIO_seek
PerlIO_set_cnt
PerlIO_set_ptrcnt
PerlIO_setlinebuf
PerlIO_stderr
PerlIO_stdin
PerlIO_stdout
PerlIO_tell
PerlIO_unread
PerlIO_write
amagic_call
amagic_deref_call
any_dup
atfork_lock
atfork_unlock
av_arylen_p
av_iter_p
block_gimme
call_atexit
call_list
calloc
cast_i32
cast_iv
cast_ulong
cast_uv
ck_warner
ck_warner_d
ckwarn
ckwarn_d
clone_params_del
clone_params_new
croak_nocontext
csighandler
cx_dump
cx_dup
cxinc
deb
deb_nocontext
debop
debprofdump
debstack
debstackptrs
delimcpy
despatch_signals
die_nocontext
dirp_dup
do_aspawn
do_binmode
do_close
do_gv_dump
do_gvgv_dump
do_hv_dump
do_join
do_magic_dump
do_op_dump
do_open
do_open9
do_openn
do_pmop_dump
do_spawn
do_spawn_nowait
do_sprintf
do_sv_dump
doing_taint
doref
dounwind
dowantarray
dump_all
dump_eval
dump_fds
dump_form
dump_indent
dump_mstats
dump_packsubs
dump_sub
dump_vindent
filter_add
filter_del
filter_read
foldEQ_latin1
form_nocontext
fp_dup
fprintf_nocontext
free_global_struct
free_tmps
get_context
get_mstats
get_op_descs
get_op_names
get_ppaddr
get_vtbl
gp_dup
gp_free
gp_ref
gv_AVadd
gv_HVadd
gv_IOadd
gv_SVadd
gv_add_by_type
gv_autoload4
gv_autoload_pv
gv_autoload_pvn
gv_autoload_sv
gv_check
gv_dump
gv_efullname
gv_efullname3
gv_efullname4
gv_fetchfile
gv_fetchfile_flags
gv_fetchpv
gv_fetchpvn_flags
gv_fetchsv
gv_fullname
gv_fullname3
gv_fullname4
gv_handler
gv_name_set
he_dup
hek_dup
hv_common
hv_common_key_len
hv_delayfree_ent
hv_eiter_p
hv_eiter_set
hv_free_ent
hv_ksplit
hv_name_set
hv_placeholders_get
hv_placeholders_p
hv_placeholders_set
hv_rand_set
hv_riter_p
hv_riter_set
init_global_struct
init_i18nl10n
init_i18nl14n
init_stacks
init_tm
instr
is_lvalue_sub
leave_scope
load_module_nocontext
magic_dump
malloc
markstack_grow
mess_nocontext
mfree
mg_dup
mg_size
mini_mktime
moreswitches
mro_get_from_name
mro_get_private_data
mro_set_mro
mro_set_private_data
my_atof
my_atof2
my_bcopy
my_bzero
my_chsize
my_cxt_index
my_cxt_init
my_dirfd
my_exit
my_failure_exit
my_fflush_all
my_fork
my_htonl
my_lstat
my_memcmp
my_memset
my_ntohl
my_pclose
my_popen
my_popen_list
my_setenv
my_socketpair
my_stat
my_strftime
my_strlcat
my_strlcpy
my_swap
newANONATTRSUB
newANONHASH
newANONLIST
newANONSUB
newATTRSUB
newAVREF
newCVREF
newFORM
newGVREF
newGVgen
newGVgen_flags
newHVREF
newHVhv
newIO
newMYSUB
newPROG
newRV
newSUB
newSVREF
newSVpvf_nocontext
new_collate
new_ctype
new_numeric
new_stackinfo
ninstr
op_dump
op_free
op_null
op_refcnt_lock
op_refcnt_unlock
parser_dup
perl_alloc_using
perl_clone_using
pmop_dump
pop_scope
pregcomp
pregexec
pregfree
pregfree2
printf_nocontext
ptr_table_clear
ptr_table_fetch
ptr_table_free
ptr_table_new
ptr_table_split
ptr_table_store
push_scope
re_compile
re_dup_guts
re_intuit_start
re_intuit_string
realloc
reentrant_free
reentrant_init
reentrant_retry
reentrant_size
ref
reg_named_buff_all
reg_named_buff_exists
reg_named_buff_fetch
reg_named_buff_firstkey
reg_named_buff_nextkey
reg_named_buff_scalar
regclass_swash
regdump
regdupe_internal
regexec_flags
regfree_internal
reginitcolors
regnext
repeatcpy
rninstr
rsignal
rsignal_state
runops_debug
runops_standard
rvpv_dup
safesyscalloc
safesysfree
safesysmalloc
safesysrealloc
save_I16
save_I32
save_I8
save_adelete
save_aelem
save_aelem_flags
save_alloc
save_aptr
save_ary
save_bool
save_clearsv
save_delete
save_destructor
save_destructor_x
save_freeop
save_freepv
save_freesv
save_generic_pvref
save_generic_svref
save_gp
save_hash
save_hdelete
save_helem
save_helem_flags
save_hints
save_hptr
save_int
save_item
save_iv
save_list
save_long
save_mortalizesv
save_nogv
save_op
save_padsv_and_mortalize
save_pptr
save_pushi32ptr
save_pushptr
save_pushptrptr
save_re_context
save_scalar
save_set_svflags
save_shared_pvref
save_sptr
save_svref
save_vptr
savestack_grow
savestack_grow_cnt
scan_num
scan_vstring
screaminstr
seed
set_context
set_numeric_local
set_numeric_radix
set_numeric_standard
share_hek
si_dup
ss_dup
stack_grow
start_subparse
str_to_version
sv_2iv
sv_2pv
sv_2uv
sv_catpvf_mg_nocontext
sv_catpvf_nocontext
sv_dump
sv_dup
sv_dup_inc
sv_peek
sv_pvn_nomg
sv_setpvf_mg_nocontext
sv_setpvf_nocontext
sv_utf8_upgrade_flags_grow
swash_fetch
swash_init
sys_init
sys_init3
sys_intern_clear
sys_intern_dup
sys_intern_init
sys_term
taint_env
taint_proper
tmps_grow
unlnk
unsharepvn
utf16_to_utf8
utf16_to_utf8_reversed
uvchr_to_utf8_flags
uvuni_to_utf8
vdeb
vform
vload_module
vnewSVpvf
vwarner
warn_nocontext
warner
warner_nocontext
whichsig
whichsig_pv
whichsig_pvn
whichsig_sv
AUTHORS
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.
SEE ALSO
perlguts, perlxs, perlxstut, perlintern
POD ERRORS
Hey! The above document had some coding errors, which are explained below:
Around line 8556:
Unterminated C<...> sequence
perl v5.18.2 2018-11-20 PERLAPI(1)