forked from schacon/perl
/
gv.c
3099 lines (2790 loc) · 85.6 KB
/
gv.c
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/* gv.c
*
* Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
* 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
*
*/
/*
* 'Mercy!' cried Gandalf. 'If the giving of information is to be the cure
* of your inquisitiveness, I shall spend all the rest of my days in answering
* you. What more do you want to know?'
* 'The names of all the stars, and of all living things, and the whole
* history of Middle-earth and Over-heaven and of the Sundering Seas,'
* laughed Pippin.
*
* [p.599 of _The Lord of the Rings_, III/xi: "The Palantír"]
*/
/*
=head1 GV Functions
A GV is a structure which corresponds to to a Perl typeglob, ie *foo.
It is a structure that holds a pointer to a scalar, an array, a hash etc,
corresponding to $foo, @foo, %foo.
GVs are usually found as values in stashes (symbol table hashes) where
Perl stores its global variables.
=cut
*/
#include "EXTERN.h"
#define PERL_IN_GV_C
#include "perl.h"
#include "overload.c"
#include "keywords.h"
static const char S_autoload[] = "AUTOLOAD";
static const STRLEN S_autolen = sizeof(S_autoload)-1;
GV *
Perl_gv_add_by_type(pTHX_ GV *gv, svtype type)
{
SV **where;
if (
!gv
|| (
SvTYPE((const SV *)gv) != SVt_PVGV
&& SvTYPE((const SV *)gv) != SVt_PVLV
)
) {
const char *what;
if (type == SVt_PVIO) {
/*
* if it walks like a dirhandle, then let's assume that
* this is a dirhandle.
*/
what = OP_IS_DIRHOP(PL_op->op_type) ?
"dirhandle" : "filehandle";
/* diag_listed_as: Bad symbol for filehandle */
} else if (type == SVt_PVHV) {
what = "hash";
} else {
what = type == SVt_PVAV ? "array" : "scalar";
}
Perl_croak(aTHX_ "Bad symbol for %s", what);
}
if (type == SVt_PVHV) {
where = (SV **)&GvHV(gv);
} else if (type == SVt_PVAV) {
where = (SV **)&GvAV(gv);
} else if (type == SVt_PVIO) {
where = (SV **)&GvIOp(gv);
} else {
where = &GvSV(gv);
}
if (!*where)
*where = newSV_type(type);
return gv;
}
GV *
Perl_gv_fetchfile(pTHX_ const char *name)
{
PERL_ARGS_ASSERT_GV_FETCHFILE;
return gv_fetchfile_flags(name, strlen(name), 0);
}
GV *
Perl_gv_fetchfile_flags(pTHX_ const char *const name, const STRLEN namelen,
const U32 flags)
{
dVAR;
char smallbuf[128];
char *tmpbuf;
const STRLEN tmplen = namelen + 2;
GV *gv;
PERL_ARGS_ASSERT_GV_FETCHFILE_FLAGS;
PERL_UNUSED_ARG(flags);
if (!PL_defstash)
return NULL;
if (tmplen <= sizeof smallbuf)
tmpbuf = smallbuf;
else
Newx(tmpbuf, tmplen, char);
/* This is where the debugger's %{"::_<$filename"} hash is created */
tmpbuf[0] = '_';
tmpbuf[1] = '<';
memcpy(tmpbuf + 2, name, namelen);
gv = *(GV**)hv_fetch(PL_defstash, tmpbuf, tmplen, TRUE);
if (!isGV(gv)) {
gv_init(gv, PL_defstash, tmpbuf, tmplen, FALSE);
#ifdef PERL_DONT_CREATE_GVSV
GvSV(gv) = newSVpvn(name, namelen);
#else
sv_setpvn(GvSV(gv), name, namelen);
#endif
}
if ((PERLDB_LINE || PERLDB_SAVESRC) && !GvAV(gv))
hv_magic(GvHVn(gv_AVadd(gv)), NULL, PERL_MAGIC_dbfile);
if (tmpbuf != smallbuf)
Safefree(tmpbuf);
return gv;
}
/*
=for apidoc gv_const_sv
If C<gv> is a typeglob whose subroutine entry is a constant sub eligible for
inlining, or C<gv> is a placeholder reference that would be promoted to such
a typeglob, then returns the value returned by the sub. Otherwise, returns
NULL.
=cut
*/
SV *
Perl_gv_const_sv(pTHX_ GV *gv)
{
PERL_ARGS_ASSERT_GV_CONST_SV;
if (SvTYPE(gv) == SVt_PVGV)
return cv_const_sv(GvCVu(gv));
return SvROK(gv) ? SvRV(gv) : NULL;
}
GP *
Perl_newGP(pTHX_ GV *const gv)
{
GP *gp;
U32 hash;
#ifdef USE_ITHREADS
const char *const file
= (PL_curcop && CopFILE(PL_curcop)) ? CopFILE(PL_curcop) : "";
const STRLEN len = strlen(file);
#else
SV *const temp_sv = CopFILESV(PL_curcop);
const char *file;
STRLEN len;
PERL_ARGS_ASSERT_NEWGP;
if (temp_sv) {
file = SvPVX(temp_sv);
len = SvCUR(temp_sv);
} else {
file = "";
len = 0;
}
#endif
PERL_HASH(hash, file, len);
Newxz(gp, 1, GP);
#ifndef PERL_DONT_CREATE_GVSV
gp->gp_sv = newSV(0);
#endif
gp->gp_line = PL_curcop ? CopLINE(PL_curcop) : 0;
/* XXX Ideally this cast would be replaced with a change to const char*
in the struct. */
gp->gp_file_hek = share_hek(file, len, hash);
gp->gp_egv = gv;
gp->gp_refcnt = 1;
return gp;
}
/* Assign CvGV(cv) = gv, handling weak references.
* See also S_anonymise_cv_maybe */
void
Perl_cvgv_set(pTHX_ CV* cv, GV* gv)
{
GV * const oldgv = CvGV(cv);
PERL_ARGS_ASSERT_CVGV_SET;
if (oldgv == gv)
return;
if (oldgv) {
if (CvCVGV_RC(cv)) {
SvREFCNT_dec(oldgv);
CvCVGV_RC_off(cv);
}
else {
sv_del_backref(MUTABLE_SV(oldgv), MUTABLE_SV(cv));
}
}
SvANY(cv)->xcv_gv = gv;
assert(!CvCVGV_RC(cv));
if (!gv)
return;
if (isGV_with_GP(gv) && GvGP(gv) && (GvCV(gv) == cv || GvFORM(gv) == cv))
Perl_sv_add_backref(aTHX_ MUTABLE_SV(gv), MUTABLE_SV(cv));
else {
CvCVGV_RC_on(cv);
SvREFCNT_inc_simple_void_NN(gv);
}
}
/* Assign CvSTASH(cv) = st, handling weak references. */
void
Perl_cvstash_set(pTHX_ CV *cv, HV *st)
{
HV *oldst = CvSTASH(cv);
PERL_ARGS_ASSERT_CVSTASH_SET;
if (oldst == st)
return;
if (oldst)
sv_del_backref(MUTABLE_SV(oldst), MUTABLE_SV(cv));
SvANY(cv)->xcv_stash = st;
if (st)
Perl_sv_add_backref(aTHX_ MUTABLE_SV(st), MUTABLE_SV(cv));
}
/*
=for apidoc 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.
C<gv> is the scalar to be converted.
C<stash> is the parent stash/package, if any.
C<name> and C<len> give the name. The name must be unqualified;
that is, it must not include the package name. If C<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.
C<flags> can be set to SVf_UTF8 if C<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).
=for apidoc gv_init
The old form of gv_init_pvn(). It does not work with UTF8 strings, as it
has no flags parameter. If the C<multi> parameter is set, the
GV_ADDMULTI flag will be passed to gv_init_pvn().
=for apidoc gv_init_pv
Same as gv_init_pvn(), but takes a nul-terminated string for the name
instead of separate char * and length parameters.
=for apidoc gv_init_sv
Same as gv_init_pvn(), but takes an SV * for the name instead of separate
char * and length parameters. C<flags> is currently unused.
=cut
*/
void
Perl_gv_init_sv(pTHX_ GV *gv, HV *stash, SV* namesv, U32 flags)
{
char *namepv;
STRLEN namelen;
PERL_ARGS_ASSERT_GV_INIT_SV;
namepv = SvPV(namesv, namelen);
if (SvUTF8(namesv))
flags |= SVf_UTF8;
gv_init_pvn(gv, stash, namepv, namelen, flags);
}
void
Perl_gv_init_pv(pTHX_ GV *gv, HV *stash, const char *name, U32 flags)
{
PERL_ARGS_ASSERT_GV_INIT_PV;
gv_init_pvn(gv, stash, name, strlen(name), flags);
}
void
Perl_gv_init_pvn(pTHX_ GV *gv, HV *stash, const char *name, STRLEN len, U32 flags)
{
dVAR;
const U32 old_type = SvTYPE(gv);
const bool doproto = old_type > SVt_NULL;
char * const proto = (doproto && SvPOK(gv)) ? SvPVX(gv) : NULL;
const STRLEN protolen = proto ? SvCUR(gv) : 0;
const U32 proto_utf8 = proto ? SvUTF8(gv) : 0;
SV *const has_constant = doproto && SvROK(gv) ? SvRV(gv) : NULL;
const U32 exported_constant = has_constant ? SvPCS_IMPORTED(gv) : 0;
PERL_ARGS_ASSERT_GV_INIT_PVN;
assert (!(proto && has_constant));
if (has_constant) {
/* The constant has to be a simple scalar type. */
switch (SvTYPE(has_constant)) {
case SVt_PVAV:
case SVt_PVHV:
case SVt_PVCV:
case SVt_PVFM:
case SVt_PVIO:
Perl_croak(aTHX_ "Cannot convert a reference to %s to typeglob",
sv_reftype(has_constant, 0));
default: NOOP;
}
SvRV_set(gv, NULL);
SvROK_off(gv);
}
if (old_type < SVt_PVGV) {
if (old_type >= SVt_PV)
SvCUR_set(gv, 0);
sv_upgrade(MUTABLE_SV(gv), SVt_PVGV);
}
if (SvLEN(gv)) {
if (proto) {
SvPV_set(gv, NULL);
SvLEN_set(gv, 0);
SvPOK_off(gv);
} else
Safefree(SvPVX_mutable(gv));
}
SvIOK_off(gv);
isGV_with_GP_on(gv);
GvGP_set(gv, Perl_newGP(aTHX_ gv));
GvSTASH(gv) = stash;
if (stash)
Perl_sv_add_backref(aTHX_ MUTABLE_SV(stash), MUTABLE_SV(gv));
gv_name_set(gv, name, len, GV_ADD | ( flags & SVf_UTF8 ? SVf_UTF8 : 0 ));
if (flags & GV_ADDMULTI || doproto) /* doproto means it */
GvMULTI_on(gv); /* _was_ mentioned */
if (doproto) { /* Replicate part of newSUB here. */
CV *cv;
ENTER;
if (has_constant) {
char *name0 = NULL;
if (name[len])
/* newCONSTSUB doesn't take a len arg, so make sure we
* give it a \0-terminated string */
name0 = savepvn(name,len);
/* newCONSTSUB takes ownership of the reference from us. */
cv = newCONSTSUB_flags(stash, (name0 ? name0 : name), flags, has_constant);
/* In case op.c:S_process_special_blocks stole it: */
if (!GvCV(gv))
GvCV_set(gv, (CV *)SvREFCNT_inc_simple_NN(cv));
assert(GvCV(gv) == cv); /* newCONSTSUB should have set this */
if (name0)
Safefree(name0);
/* If this reference was a copy of another, then the subroutine
must have been "imported", by a Perl space assignment to a GV
from a reference to CV. */
if (exported_constant)
GvIMPORTED_CV_on(gv);
} else {
(void) start_subparse(0,0); /* Create empty CV in compcv. */
cv = PL_compcv;
GvCV_set(gv,cv);
}
LEAVE;
mro_method_changed_in(GvSTASH(gv)); /* sub Foo::bar($) { (shift) } sub ASDF::baz($); *ASDF::baz = \&Foo::bar */
CvGV_set(cv, gv);
CvFILE_set_from_cop(cv, PL_curcop);
CvSTASH_set(cv, PL_curstash);
if (proto) {
sv_usepvn_flags(MUTABLE_SV(cv), proto, protolen,
SV_HAS_TRAILING_NUL);
if ( proto_utf8 ) SvUTF8_on(MUTABLE_SV(cv));
}
}
}
STATIC void
S_gv_init_svtype(pTHX_ GV *gv, const svtype sv_type)
{
PERL_ARGS_ASSERT_GV_INIT_SVTYPE;
switch (sv_type) {
case SVt_PVIO:
(void)GvIOn(gv);
break;
case SVt_PVAV:
(void)GvAVn(gv);
break;
case SVt_PVHV:
(void)GvHVn(gv);
break;
#ifdef PERL_DONT_CREATE_GVSV
case SVt_NULL:
case SVt_PVCV:
case SVt_PVFM:
case SVt_PVGV:
break;
default:
if(GvSVn(gv)) {
/* Work round what appears to be a bug in Sun C++ 5.8 2005/10/13
If we just cast GvSVn(gv) to void, it ignores evaluating it for
its side effect */
}
#endif
}
}
static void core_xsub(pTHX_ CV* cv);
static GV *
S_maybe_add_coresub(pTHX_ HV * const stash, GV *gv,
const char * const name, const STRLEN len,
const char * const fullname, STRLEN const fullen)
{
const int code = keyword(name, len, 1);
static const char file[] = __FILE__;
CV *cv, *oldcompcv = NULL;
int opnum = 0;
SV *opnumsv;
bool ampable = TRUE; /* &{}-able */
COP *oldcurcop = NULL;
yy_parser *oldparser = NULL;
I32 oldsavestack_ix = 0;
assert(gv || stash);
assert(name);
assert(stash || fullname);
if (!fullname && !HvENAME(stash)) return NULL; /* pathological case
that would require
inlining newATTRSUB */
if (code >= 0) return NULL; /* not overridable */
switch (-code) {
/* no support for \&CORE::infix;
no support for funcs that take labels, as their parsing is
weird */
case KEY_and: case KEY_cmp: case KEY_CORE: case KEY_dump:
case KEY_eq: case KEY_ge:
case KEY_gt: case KEY_le: case KEY_lt: case KEY_ne:
case KEY_or: case KEY_x: case KEY_xor:
return NULL;
case KEY_chdir:
case KEY_chomp: case KEY_chop:
case KEY_each: case KEY_eof: case KEY_exec:
case KEY_keys:
case KEY_lstat:
case KEY_pop:
case KEY_push:
case KEY_shift:
case KEY_splice:
case KEY_stat:
case KEY_system:
case KEY_truncate: case KEY_unlink:
case KEY_unshift:
case KEY_values:
ampable = FALSE;
}
if (!gv) {
gv = (GV *)newSV(0);
gv_init(gv, stash, name, len, TRUE);
}
if (ampable) {
ENTER;
oldcurcop = PL_curcop;
oldparser = PL_parser;
lex_start(NULL, NULL, 0);
oldcompcv = PL_compcv;
PL_compcv = NULL; /* Prevent start_subparse from setting
CvOUTSIDE. */
oldsavestack_ix = start_subparse(FALSE,0);
cv = PL_compcv;
}
else {
/* Avoid calling newXS, as it calls us, and things start to
get hairy. */
cv = MUTABLE_CV(newSV_type(SVt_PVCV));
GvCV_set(gv,cv);
GvCVGEN(gv) = 0;
mro_method_changed_in(GvSTASH(gv));
CvISXSUB_on(cv);
CvXSUB(cv) = core_xsub;
}
CvGV_set(cv, gv); /* This stops new ATTRSUB from setting CvFILE
from PL_curcop. */
(void)gv_fetchfile(file);
CvFILE(cv) = (char *)file;
/* XXX This is inefficient, as doing things this order causes
a prototype check in newATTRSUB. But we have to do
it this order as we need an op number before calling
new ATTRSUB. */
(void)core_prototype((SV *)cv, name, code, &opnum);
if (stash && (fullname || !fullen))
(void)hv_store(stash,name,len,(SV *)gv,0);
if (ampable) {
SV *tmpstr;
CvLVALUE_on(cv);
if (!fullname) {
tmpstr = newSVhek(HvENAME_HEK(stash));
sv_catpvs(tmpstr, "::");
sv_catpvn(tmpstr,name,len);
}
else tmpstr = newSVpvn_share(fullname,fullen,0);
newATTRSUB(oldsavestack_ix,
newSVOP(OP_CONST, 0, tmpstr),
NULL,NULL,
coresub_op(
opnum
? newSVuv((UV)opnum)
: newSVpvn(name,len),
code, opnum
)
);
assert(GvCV(gv) == cv);
if (opnum != OP_VEC && opnum != OP_SUBSTR)
CvLVALUE_off(cv); /* Now *that* was a neat trick. */
LEAVE;
PL_parser = oldparser;
PL_curcop = oldcurcop;
PL_compcv = oldcompcv;
}
opnumsv = opnum ? newSVuv((UV)opnum) : (SV *)NULL;
cv_set_call_checker(
cv, Perl_ck_entersub_args_core, opnumsv ? opnumsv : (SV *)cv
);
SvREFCNT_dec(opnumsv);
return gv;
}
/*
=for apidoc gv_fetchmeth
Like L</gv_fetchmeth_pvn>, but lacks a flags parameter.
=for apidoc gv_fetchmeth_sv
Exactly like L</gv_fetchmeth_pvn>, but takes the name string in the form
of an SV instead of a string/length pair.
=cut
*/
GV *
Perl_gv_fetchmeth_sv(pTHX_ HV *stash, SV *namesv, I32 level, U32 flags)
{
char *namepv;
STRLEN namelen;
PERL_ARGS_ASSERT_GV_FETCHMETH_SV;
namepv = SvPV(namesv, namelen);
if (SvUTF8(namesv))
flags |= SVf_UTF8;
return gv_fetchmeth_pvn(stash, namepv, namelen, level, flags);
}
/*
=for apidoc gv_fetchmeth_pv
Exactly like L</gv_fetchmeth_pvn>, but takes a nul-terminated string
instead of a string/length pair.
=cut
*/
GV *
Perl_gv_fetchmeth_pv(pTHX_ HV *stash, const char *name, I32 level, U32 flags)
{
PERL_ARGS_ASSERT_GV_FETCHMETH_PV;
return gv_fetchmeth_pvn(stash, name, strlen(name), level, flags);
}
/*
=for apidoc gv_fetchmeth_pvn
Returns the glob with the given C<name> and a defined subroutine or
C<NULL>. The glob lives in the given C<stash>, or in the stashes
accessible via @ISA and UNIVERSAL::.
The argument C<level> should be either 0 or -1. If C<level==0>, as a
side-effect creates a glob with the given C<name> in the given C<stash>
which in the case of success contains an alias for the subroutine, and sets
up caching info for this glob.
Currently, the only significant value for C<flags> is SVf_UTF8.
This function grants C<"SUPER"> token as a postfix of the stash name. The
GV returned from C<gv_fetchmeth> may be a method cache entry, which is not
visible to Perl code. So when calling C<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 C<GvCV> macro.
=cut
*/
/* NOTE: No support for tied ISA */
GV *
Perl_gv_fetchmeth_pvn(pTHX_ HV *stash, const char *name, STRLEN len, I32 level, U32 flags)
{
dVAR;
GV** gvp;
AV* linear_av;
SV** linear_svp;
SV* linear_sv;
HV* cstash;
GV* candidate = NULL;
CV* cand_cv = NULL;
GV* topgv = NULL;
const char *hvname;
I32 create = (level >= 0) ? 1 : 0;
I32 items;
STRLEN packlen;
U32 topgen_cmp;
U32 is_utf8 = flags & SVf_UTF8;
PERL_ARGS_ASSERT_GV_FETCHMETH_PVN;
/* UNIVERSAL methods should be callable without a stash */
if (!stash) {
create = 0; /* probably appropriate */
if(!(stash = gv_stashpvs("UNIVERSAL", 0)))
return 0;
}
assert(stash);
hvname = HvNAME_get(stash);
if (!hvname)
Perl_croak(aTHX_ "Can't use anonymous symbol table for method lookup");
assert(hvname);
assert(name);
DEBUG_o( Perl_deb(aTHX_ "Looking for method %s in package %s\n",name,hvname) );
topgen_cmp = HvMROMETA(stash)->cache_gen + PL_sub_generation;
/* check locally for a real method or a cache entry */
gvp = (GV**)hv_fetch(stash, name, is_utf8 ? -(I32)len : (I32)len, create);
if(gvp) {
topgv = *gvp;
have_gv:
assert(topgv);
if (SvTYPE(topgv) != SVt_PVGV)
gv_init_pvn(topgv, stash, name, len, GV_ADDMULTI|is_utf8);
if ((cand_cv = GvCV(topgv))) {
/* If genuine method or valid cache entry, use it */
if (!GvCVGEN(topgv) || GvCVGEN(topgv) == topgen_cmp) {
return topgv;
}
else {
/* stale cache entry, junk it and move on */
SvREFCNT_dec(cand_cv);
GvCV_set(topgv, NULL);
cand_cv = NULL;
GvCVGEN(topgv) = 0;
}
}
else if (GvCVGEN(topgv) == topgen_cmp) {
/* cache indicates no such method definitively */
return 0;
}
else if (len > 1 /* shortest is uc */ && HvNAMELEN_get(stash) == 4
&& strnEQ(hvname, "CORE", 4)
&& S_maybe_add_coresub(aTHX_ stash,topgv,name,len,0,1))
goto have_gv;
}
packlen = HvNAMELEN_get(stash);
if (packlen >= 7 && strEQ(hvname + packlen - 7, "::SUPER")) {
HV* basestash;
packlen -= 7;
basestash = gv_stashpvn(hvname, packlen,
GV_ADD | (HvNAMEUTF8(stash) ? SVf_UTF8 : 0));
linear_av = mro_get_linear_isa(basestash);
}
else {
linear_av = mro_get_linear_isa(stash); /* has ourselves at the top of the list */
}
linear_svp = AvARRAY(linear_av) + 1; /* skip over self */
items = AvFILLp(linear_av); /* no +1, to skip over self */
while (items--) {
linear_sv = *linear_svp++;
assert(linear_sv);
cstash = gv_stashsv(linear_sv, 0);
if (!cstash) {
Perl_ck_warner(aTHX_ packWARN(WARN_SYNTAX),
"Can't locate package %"SVf" for @%"HEKf"::ISA",
SVfARG(linear_sv),
HEKfARG(HvNAME_HEK(stash)));
continue;
}
assert(cstash);
gvp = (GV**)hv_fetch(cstash, name, is_utf8 ? -(I32)len : (I32)len, 0);
if (!gvp) {
if (len > 1 && HvNAMELEN_get(cstash) == 4) {
const char *hvname = HvNAME(cstash); assert(hvname);
if (strnEQ(hvname, "CORE", 4)
&& (candidate =
S_maybe_add_coresub(aTHX_ cstash,NULL,name,len,0,0)
))
goto have_candidate;
}
continue;
}
else candidate = *gvp;
have_candidate:
assert(candidate);
if (SvTYPE(candidate) != SVt_PVGV)
gv_init_pvn(candidate, cstash, name, len, GV_ADDMULTI|is_utf8);
if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
/*
* Found real method, cache method in topgv if:
* 1. topgv has no synonyms (else inheritance crosses wires)
* 2. method isn't a stub (else AUTOLOAD fails spectacularly)
*/
if (topgv && (GvREFCNT(topgv) == 1) && (CvROOT(cand_cv) || CvXSUB(cand_cv))) {
CV *old_cv = GvCV(topgv);
SvREFCNT_dec(old_cv);
SvREFCNT_inc_simple_void_NN(cand_cv);
GvCV_set(topgv, cand_cv);
GvCVGEN(topgv) = topgen_cmp;
}
return candidate;
}
}
/* Check UNIVERSAL without caching */
if(level == 0 || level == -1) {
candidate = gv_fetchmeth_pvn(NULL, name, len, 1, flags);
if(candidate) {
cand_cv = GvCV(candidate);
if (topgv && (GvREFCNT(topgv) == 1) && (CvROOT(cand_cv) || CvXSUB(cand_cv))) {
CV *old_cv = GvCV(topgv);
SvREFCNT_dec(old_cv);
SvREFCNT_inc_simple_void_NN(cand_cv);
GvCV_set(topgv, cand_cv);
GvCVGEN(topgv) = topgen_cmp;
}
return candidate;
}
}
if (topgv && GvREFCNT(topgv) == 1) {
/* cache the fact that the method is not defined */
GvCVGEN(topgv) = topgen_cmp;
}
return 0;
}
/*
=for apidoc gv_fetchmeth_autoload
This is the old form of L</gv_fetchmeth_pvn_autoload>, which has no flags
parameter.
=for apidoc gv_fetchmeth_sv_autoload
Exactly like L</gv_fetchmeth_pvn_autoload>, but takes the name string in the form
of an SV instead of a string/length pair.
=cut
*/
GV *
Perl_gv_fetchmeth_sv_autoload(pTHX_ HV *stash, SV *namesv, I32 level, U32 flags)
{
char *namepv;
STRLEN namelen;
PERL_ARGS_ASSERT_GV_FETCHMETH_SV_AUTOLOAD;
namepv = SvPV(namesv, namelen);
if (SvUTF8(namesv))
flags |= SVf_UTF8;
return gv_fetchmeth_pvn_autoload(stash, namepv, namelen, level, flags);
}
/*
=for apidoc gv_fetchmeth_pv_autoload
Exactly like L</gv_fetchmeth_pvn_autoload>, but takes a nul-terminated string
instead of a string/length pair.
=cut
*/
GV *
Perl_gv_fetchmeth_pv_autoload(pTHX_ HV *stash, const char *name, I32 level, U32 flags)
{
PERL_ARGS_ASSERT_GV_FETCHMETH_PV_AUTOLOAD;
return gv_fetchmeth_pvn_autoload(stash, name, strlen(name), level, flags);
}
/*
=for apidoc 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 C<level < 0>. For an autoloaded subroutine without a stub, GvCV()
of the result may be zero.
Currently, the only significant value for C<flags> is SVf_UTF8.
=cut
*/
GV *
Perl_gv_fetchmeth_pvn_autoload(pTHX_ HV *stash, const char *name, STRLEN len, I32 level, U32 flags)
{
GV *gv = gv_fetchmeth_pvn(stash, name, len, level, flags);
PERL_ARGS_ASSERT_GV_FETCHMETH_PVN_AUTOLOAD;
if (!gv) {
CV *cv;
GV **gvp;
if (!stash)
return NULL; /* UNIVERSAL::AUTOLOAD could cause trouble */
if (len == S_autolen && memEQ(name, S_autoload, S_autolen))
return NULL;
if (!(gv = gv_fetchmeth_pvn(stash, S_autoload, S_autolen, FALSE, flags)))
return NULL;
cv = GvCV(gv);
if (!(CvROOT(cv) || CvXSUB(cv)))
return NULL;
/* Have an autoload */
if (level < 0) /* Cannot do without a stub */
gv_fetchmeth_pvn(stash, name, len, 0, flags);
gvp = (GV**)hv_fetch(stash, name,
(flags & SVf_UTF8) ? -(I32)len : (I32)len, (level >= 0));
if (!gvp)
return NULL;
return *gvp;
}
return gv;
}
/*
=for apidoc gv_fetchmethod_autoload
Returns the glob which contains the subroutine to call to invoke the method
on the C<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 C<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 C<gv_fetchmethod> is equivalent to calling C<gv_fetchmethod_autoload>
with a non-zero C<autoload> parameter.
These functions grant C<"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 C<gv_fetchmeth> with
C<level==0>. C<name> should be writable if contains C<':'> or C<'
''>. The warning against passing the GV returned by C<gv_fetchmeth> to
C<call_sv> apply equally to these functions.
=cut
*/
STATIC HV*
S_gv_get_super_pkg(pTHX_ const char* name, I32 namelen, U32 flags)
{
AV* superisa;
GV** gvp;
GV* gv;
HV* stash;
PERL_ARGS_ASSERT_GV_GET_SUPER_PKG;
stash = gv_stashpvn(name, namelen, flags);
if(stash) return stash;
/* If we must create it, give it an @ISA array containing
the real package this SUPER is for, so that it's tied
into the cache invalidation code correctly */
stash = gv_stashpvn(name, namelen, GV_ADD | flags);
gvp = (GV**)hv_fetchs(stash, "ISA", TRUE);
gv = *gvp;
gv_init(gv, stash, "ISA", 3, TRUE);
superisa = GvAVn(gv);
GvMULTI_on(gv);
sv_magic(MUTABLE_SV(superisa), MUTABLE_SV(gv), PERL_MAGIC_isa, NULL, 0);
#ifdef USE_ITHREADS
av_push(superisa, newSVpvn_flags(CopSTASHPV(PL_curcop),
strlen(CopSTASHPV(PL_curcop)),
CopSTASH_flags(PL_curcop)
));
#else
av_push(superisa, newSVhek(CopSTASH(PL_curcop)
? HvNAME_HEK(CopSTASH(PL_curcop)) : NULL));
#endif
return stash;
}
GV *
Perl_gv_fetchmethod_autoload(pTHX_ HV *stash, const char *name, I32 autoload)
{
PERL_ARGS_ASSERT_GV_FETCHMETHOD_AUTOLOAD;
return gv_fetchmethod_flags(stash, name, autoload ? GV_AUTOLOAD : 0);
}
GV *
Perl_gv_fetchmethod_sv_flags(pTHX_ HV *stash, SV *namesv, U32 flags)
{
char *namepv;
STRLEN namelen;
PERL_ARGS_ASSERT_GV_FETCHMETHOD_SV_FLAGS;
namepv = SvPV(namesv, namelen);
if (SvUTF8(namesv))
flags |= SVf_UTF8;
return gv_fetchmethod_pvn_flags(stash, namepv, namelen, flags);
}
GV *
Perl_gv_fetchmethod_pv_flags(pTHX_ HV *stash, const char *name, U32 flags)
{
PERL_ARGS_ASSERT_GV_FETCHMETHOD_PV_FLAGS;
return gv_fetchmethod_pvn_flags(stash, name, strlen(name), flags);
}
/* Don't merge this yet, as it's likely to get a len parameter, and possibly
even a U32 hash */
GV *
Perl_gv_fetchmethod_pvn_flags(pTHX_ HV *stash, const char *name, const STRLEN len, U32 flags)
{
dVAR;
register const char *nend;
const char *nsplit = NULL;
GV* gv;
HV* ostash = stash;
const char * const origname = name;
SV *const error_report = MUTABLE_SV(stash);
const U32 autoload = flags & GV_AUTOLOAD;
const U32 do_croak = flags & GV_CROAK;
const U32 is_utf8 = flags & SVf_UTF8;
PERL_ARGS_ASSERT_GV_FETCHMETHOD_PVN_FLAGS;
if (SvTYPE(stash) < SVt_PVHV)
stash = NULL;
else {
/* The only way stash can become NULL later on is if nsplit is set,
which in turn means that there is no need for a SVt_PVHV case
the error reporting code. */
}
for (nend = name; *nend || nend != (origname + len); nend++) {
if (*nend == '\'') {
nsplit = nend;
name = nend + 1;
}
else if (*nend == ':' && *(nend + 1) == ':') {
nsplit = nend++;
name = nend + 1;