3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
12 * 'Mercy!' cried Gandalf. 'If the giving of information is to be the cure
13 * of your inquisitiveness, I shall spend all the rest of my days in answering
14 * you. What more do you want to know?'
15 * 'The names of all the stars, and of all living things, and the whole
16 * history of Middle-earth and Over-heaven and of the Sundering Seas,'
19 * [p.599 of _The Lord of the Rings_, III/xi: "The PalantÃr"]
25 A GV is a structure which corresponds to to a Perl typeglob, ie *foo.
26 It is a structure that holds a pointer to a scalar, an array, a hash etc,
27 corresponding to $foo, @foo, %foo.
29 GVs are usually found as values in stashes (symbol table hashes) where
30 Perl stores its global variables.
40 static const char S_autoload[] = "AUTOLOAD";
41 static const STRLEN S_autolen = sizeof(S_autoload)-1;
44 Perl_gv_add_by_type(pTHX_ GV *gv, svtype type)
48 if (!gv || SvTYPE((const SV *)gv) != SVt_PVGV) {
50 if (type == SVt_PVIO) {
52 * if it walks like a dirhandle, then let's assume that
53 * this is a dirhandle.
55 what = PL_op->op_type == OP_READDIR ||
56 PL_op->op_type == OP_TELLDIR ||
57 PL_op->op_type == OP_SEEKDIR ||
58 PL_op->op_type == OP_REWINDDIR ||
59 PL_op->op_type == OP_CLOSEDIR ?
60 "dirhandle" : "filehandle";
61 /* diag_listed_as: Bad symbol for filehandle */
62 } else if (type == SVt_PVHV) {
65 what = type == SVt_PVAV ? "array" : "scalar";
67 Perl_croak(aTHX_ "Bad symbol for %s", what);
70 if (type == SVt_PVHV) {
71 where = (SV **)&GvHV(gv);
72 } else if (type == SVt_PVAV) {
73 where = (SV **)&GvAV(gv);
74 } else if (type == SVt_PVIO) {
75 where = (SV **)&GvIOp(gv);
81 *where = newSV_type(type);
86 Perl_gv_fetchfile(pTHX_ const char *name)
88 PERL_ARGS_ASSERT_GV_FETCHFILE;
89 return gv_fetchfile_flags(name, strlen(name), 0);
93 Perl_gv_fetchfile_flags(pTHX_ const char *const name, const STRLEN namelen,
99 const STRLEN tmplen = namelen + 2;
102 PERL_ARGS_ASSERT_GV_FETCHFILE_FLAGS;
103 PERL_UNUSED_ARG(flags);
108 if (tmplen <= sizeof smallbuf)
111 Newx(tmpbuf, tmplen, char);
112 /* This is where the debugger's %{"::_<$filename"} hash is created */
115 memcpy(tmpbuf + 2, name, namelen);
116 gv = *(GV**)hv_fetch(PL_defstash, tmpbuf, tmplen, TRUE);
118 gv_init(gv, PL_defstash, tmpbuf, tmplen, FALSE);
119 #ifdef PERL_DONT_CREATE_GVSV
120 GvSV(gv) = newSVpvn(name, namelen);
122 sv_setpvn(GvSV(gv), name, namelen);
124 if (PERLDB_LINE || PERLDB_SAVESRC)
125 hv_magic(GvHVn(gv_AVadd(gv)), NULL, PERL_MAGIC_dbfile);
127 if (tmpbuf != smallbuf)
133 =for apidoc gv_const_sv
135 If C<gv> is a typeglob whose subroutine entry is a constant sub eligible for
136 inlining, or C<gv> is a placeholder reference that would be promoted to such
137 a typeglob, then returns the value returned by the sub. Otherwise, returns
144 Perl_gv_const_sv(pTHX_ GV *gv)
146 PERL_ARGS_ASSERT_GV_CONST_SV;
148 if (SvTYPE(gv) == SVt_PVGV)
149 return cv_const_sv(GvCVu(gv));
150 return SvROK(gv) ? SvRV(gv) : NULL;
154 Perl_newGP(pTHX_ GV *const gv)
159 const char *const file
160 = (PL_curcop && CopFILE(PL_curcop)) ? CopFILE(PL_curcop) : "";
161 const STRLEN len = strlen(file);
163 SV *const temp_sv = CopFILESV(PL_curcop);
167 PERL_ARGS_ASSERT_NEWGP;
170 file = SvPVX(temp_sv);
171 len = SvCUR(temp_sv);
178 PERL_HASH(hash, file, len);
182 #ifndef PERL_DONT_CREATE_GVSV
183 gp->gp_sv = newSV(0);
186 gp->gp_line = PL_curcop ? CopLINE(PL_curcop) : 0;
187 /* XXX Ideally this cast would be replaced with a change to const char*
189 gp->gp_file_hek = share_hek(file, len, hash);
196 /* Assign CvGV(cv) = gv, handling weak references.
197 * See also S_anonymise_cv_maybe */
200 Perl_cvgv_set(pTHX_ CV* cv, GV* gv)
202 GV * const oldgv = CvGV(cv);
203 PERL_ARGS_ASSERT_CVGV_SET;
214 sv_del_backref(MUTABLE_SV(oldgv), MUTABLE_SV(cv));
218 SvANY(cv)->xcv_gv = gv;
219 assert(!CvCVGV_RC(cv));
224 if (isGV_with_GP(gv) && GvGP(gv) && (GvCV(gv) == cv || GvFORM(gv) == cv))
225 Perl_sv_add_backref(aTHX_ MUTABLE_SV(gv), MUTABLE_SV(cv));
228 SvREFCNT_inc_simple_void_NN(gv);
234 Perl_gv_init(pTHX_ GV *gv, HV *stash, const char *name, STRLEN len, int multi)
237 const U32 old_type = SvTYPE(gv);
238 const bool doproto = old_type > SVt_NULL;
239 char * const proto = (doproto && SvPOK(gv)) ? SvPVX(gv) : NULL;
240 const STRLEN protolen = proto ? SvCUR(gv) : 0;
241 SV *const has_constant = doproto && SvROK(gv) ? SvRV(gv) : NULL;
242 const U32 exported_constant = has_constant ? SvPCS_IMPORTED(gv) : 0;
244 PERL_ARGS_ASSERT_GV_INIT;
245 assert (!(proto && has_constant));
248 /* The constant has to be a simple scalar type. */
249 switch (SvTYPE(has_constant)) {
255 Perl_croak(aTHX_ "Cannot convert a reference to %s to typeglob",
256 sv_reftype(has_constant, 0));
264 if (old_type < SVt_PVGV) {
265 if (old_type >= SVt_PV)
267 sv_upgrade(MUTABLE_SV(gv), SVt_PVGV);
275 Safefree(SvPVX_mutable(gv));
280 GvGP(gv) = Perl_newGP(aTHX_ gv);
283 Perl_sv_add_backref(aTHX_ MUTABLE_SV(stash), MUTABLE_SV(gv));
284 gv_name_set(gv, name, len, GV_ADD);
285 if (multi || doproto) /* doproto means it _was_ mentioned */
287 if (doproto) { /* Replicate part of newSUB here. */
293 /* newCONSTSUB doesn't take a len arg, so make sure we
294 * give it a \0-terminated string */
295 name0 = savepvn(name,len);
297 /* newCONSTSUB takes ownership of the reference from us. */
298 cv = newCONSTSUB(stash, (name0 ? name0 : name), has_constant);
299 assert(GvCV(gv) == cv); /* newCONSTSUB should have set this */
302 /* If this reference was a copy of another, then the subroutine
303 must have been "imported", by a Perl space assignment to a GV
304 from a reference to CV. */
305 if (exported_constant)
306 GvIMPORTED_CV_on(gv);
308 (void) start_subparse(0,0); /* Create empty CV in compcv. */
314 mro_method_changed_in(GvSTASH(gv)); /* sub Foo::bar($) { (shift) } sub ASDF::baz($); *ASDF::baz = \&Foo::bar */
316 CvFILE_set_from_cop(cv, PL_curcop);
317 CvSTASH(cv) = PL_curstash;
319 Perl_sv_add_backref(aTHX_ MUTABLE_SV(PL_curstash), MUTABLE_SV(cv));
321 sv_usepvn_flags(MUTABLE_SV(cv), proto, protolen,
322 SV_HAS_TRAILING_NUL);
328 S_gv_init_sv(pTHX_ GV *gv, const svtype sv_type)
330 PERL_ARGS_ASSERT_GV_INIT_SV;
342 #ifdef PERL_DONT_CREATE_GVSV
350 /* Work round what appears to be a bug in Sun C++ 5.8 2005/10/13
351 If we just cast GvSVn(gv) to void, it ignores evaluating it for
359 =for apidoc gv_fetchmeth
361 Returns the glob with the given C<name> and a defined subroutine or
362 C<NULL>. The glob lives in the given C<stash>, or in the stashes
363 accessible via @ISA and UNIVERSAL::.
365 The argument C<level> should be either 0 or -1. If C<level==0>, as a
366 side-effect creates a glob with the given C<name> in the given C<stash>
367 which in the case of success contains an alias for the subroutine, and sets
368 up caching info for this glob.
370 This function grants C<"SUPER"> token as a postfix of the stash name. The
371 GV returned from C<gv_fetchmeth> may be a method cache entry, which is not
372 visible to Perl code. So when calling C<call_sv>, you should not use
373 the GV directly; instead, you should use the method's CV, which can be
374 obtained from the GV with the C<GvCV> macro.
379 /* NOTE: No support for tied ISA */
382 Perl_gv_fetchmeth(pTHX_ HV *stash, const char *name, STRLEN len, I32 level)
390 GV* candidate = NULL;
395 I32 create = (level >= 0) ? 1 : 0;
400 PERL_ARGS_ASSERT_GV_FETCHMETH;
402 /* UNIVERSAL methods should be callable without a stash */
404 create = 0; /* probably appropriate */
405 if(!(stash = gv_stashpvs("UNIVERSAL", 0)))
411 hvname = HvNAME_get(stash);
413 Perl_croak(aTHX_ "Can't use anonymous symbol table for method lookup");
418 DEBUG_o( Perl_deb(aTHX_ "Looking for method %s in package %s\n",name,hvname) );
420 topgen_cmp = HvMROMETA(stash)->cache_gen + PL_sub_generation;
422 /* check locally for a real method or a cache entry */
423 gvp = (GV**)hv_fetch(stash, name, len, create);
427 if (SvTYPE(topgv) != SVt_PVGV)
428 gv_init(topgv, stash, name, len, TRUE);
429 if ((cand_cv = GvCV(topgv))) {
430 /* If genuine method or valid cache entry, use it */
431 if (!GvCVGEN(topgv) || GvCVGEN(topgv) == topgen_cmp) {
435 /* stale cache entry, junk it and move on */
436 SvREFCNT_dec(cand_cv);
437 GvCV(topgv) = cand_cv = NULL;
441 else if (GvCVGEN(topgv) == topgen_cmp) {
442 /* cache indicates no such method definitively */
447 packlen = HvNAMELEN_get(stash);
448 if (packlen >= 7 && strEQ(hvname + packlen - 7, "::SUPER")) {
451 basestash = gv_stashpvn(hvname, packlen, GV_ADD);
452 linear_av = mro_get_linear_isa(basestash);
455 linear_av = mro_get_linear_isa(stash); /* has ourselves at the top of the list */
458 linear_svp = AvARRAY(linear_av) + 1; /* skip over self */
459 items = AvFILLp(linear_av); /* no +1, to skip over self */
461 linear_sv = *linear_svp++;
463 cstash = gv_stashsv(linear_sv, 0);
466 Perl_ck_warner(aTHX_ packWARN(WARN_SYNTAX), "Can't locate package %"SVf" for @%s::ISA",
467 SVfARG(linear_sv), hvname);
473 gvp = (GV**)hv_fetch(cstash, name, len, 0);
477 if (SvTYPE(candidate) != SVt_PVGV) gv_init(candidate, cstash, name, len, TRUE);
478 if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
480 * Found real method, cache method in topgv if:
481 * 1. topgv has no synonyms (else inheritance crosses wires)
482 * 2. method isn't a stub (else AUTOLOAD fails spectacularly)
484 if (topgv && (GvREFCNT(topgv) == 1) && (CvROOT(cand_cv) || CvXSUB(cand_cv))) {
485 if ((old_cv = GvCV(topgv))) SvREFCNT_dec(old_cv);
486 SvREFCNT_inc_simple_void_NN(cand_cv);
487 GvCV(topgv) = cand_cv;
488 GvCVGEN(topgv) = topgen_cmp;
494 /* Check UNIVERSAL without caching */
495 if(level == 0 || level == -1) {
496 candidate = gv_fetchmeth(NULL, name, len, 1);
498 cand_cv = GvCV(candidate);
499 if (topgv && (GvREFCNT(topgv) == 1) && (CvROOT(cand_cv) || CvXSUB(cand_cv))) {
500 if ((old_cv = GvCV(topgv))) SvREFCNT_dec(old_cv);
501 SvREFCNT_inc_simple_void_NN(cand_cv);
502 GvCV(topgv) = cand_cv;
503 GvCVGEN(topgv) = topgen_cmp;
509 if (topgv && GvREFCNT(topgv) == 1) {
510 /* cache the fact that the method is not defined */
511 GvCVGEN(topgv) = topgen_cmp;
518 =for apidoc gv_fetchmeth_autoload
520 Same as gv_fetchmeth(), but looks for autoloaded subroutines too.
521 Returns a glob for the subroutine.
523 For an autoloaded subroutine without a GV, will create a GV even
524 if C<level < 0>. For an autoloaded subroutine without a stub, GvCV()
525 of the result may be zero.
531 Perl_gv_fetchmeth_autoload(pTHX_ HV *stash, const char *name, STRLEN len, I32 level)
533 GV *gv = gv_fetchmeth(stash, name, len, level);
535 PERL_ARGS_ASSERT_GV_FETCHMETH_AUTOLOAD;
542 return NULL; /* UNIVERSAL::AUTOLOAD could cause trouble */
543 if (len == S_autolen && memEQ(name, S_autoload, S_autolen))
545 if (!(gv = gv_fetchmeth(stash, S_autoload, S_autolen, FALSE)))
548 if (!(CvROOT(cv) || CvXSUB(cv)))
550 /* Have an autoload */
551 if (level < 0) /* Cannot do without a stub */
552 gv_fetchmeth(stash, name, len, 0);
553 gvp = (GV**)hv_fetch(stash, name, len, (level >= 0));
562 =for apidoc gv_fetchmethod_autoload
564 Returns the glob which contains the subroutine to call to invoke the method
565 on the C<stash>. In fact in the presence of autoloading this may be the
566 glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD is
569 The third parameter of C<gv_fetchmethod_autoload> determines whether
570 AUTOLOAD lookup is performed if the given method is not present: non-zero
571 means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD.
572 Calling C<gv_fetchmethod> is equivalent to calling C<gv_fetchmethod_autoload>
573 with a non-zero C<autoload> parameter.
575 These functions grant C<"SUPER"> token as a prefix of the method name. Note
576 that if you want to keep the returned glob for a long time, you need to
577 check for it being "AUTOLOAD", since at the later time the call may load a
578 different subroutine due to $AUTOLOAD changing its value. Use the glob
579 created via a side effect to do this.
581 These functions have the same side-effects and as C<gv_fetchmeth> with
582 C<level==0>. C<name> should be writable if contains C<':'> or C<'
583 ''>. The warning against passing the GV returned by C<gv_fetchmeth> to
584 C<call_sv> apply equally to these functions.
590 S_gv_get_super_pkg(pTHX_ const char* name, I32 namelen)
597 PERL_ARGS_ASSERT_GV_GET_SUPER_PKG;
599 stash = gv_stashpvn(name, namelen, 0);
600 if(stash) return stash;
602 /* If we must create it, give it an @ISA array containing
603 the real package this SUPER is for, so that it's tied
604 into the cache invalidation code correctly */
605 stash = gv_stashpvn(name, namelen, GV_ADD);
606 gvp = (GV**)hv_fetchs(stash, "ISA", TRUE);
608 gv_init(gv, stash, "ISA", 3, TRUE);
609 superisa = GvAVn(gv);
611 sv_magic(MUTABLE_SV(superisa), MUTABLE_SV(gv), PERL_MAGIC_isa, NULL, 0);
613 av_push(superisa, newSVpv(CopSTASHPV(PL_curcop), 0));
615 av_push(superisa, newSVhek(CopSTASH(PL_curcop)
616 ? HvNAME_HEK(CopSTASH(PL_curcop)) : NULL));
623 Perl_gv_fetchmethod_autoload(pTHX_ HV *stash, const char *name, I32 autoload)
625 PERL_ARGS_ASSERT_GV_FETCHMETHOD_AUTOLOAD;
627 return gv_fetchmethod_flags(stash, name, autoload ? GV_AUTOLOAD : 0);
630 /* Don't merge this yet, as it's likely to get a len parameter, and possibly
633 Perl_gv_fetchmethod_flags(pTHX_ HV *stash, const char *name, U32 flags)
636 register const char *nend;
637 const char *nsplit = NULL;
640 const char * const origname = name;
641 SV *const error_report = MUTABLE_SV(stash);
642 const U32 autoload = flags & GV_AUTOLOAD;
643 const U32 do_croak = flags & GV_CROAK;
645 PERL_ARGS_ASSERT_GV_FETCHMETHOD_FLAGS;
647 if (SvTYPE(stash) < SVt_PVHV)
650 /* The only way stash can become NULL later on is if nsplit is set,
651 which in turn means that there is no need for a SVt_PVHV case
652 the error reporting code. */
655 for (nend = name; *nend; nend++) {
660 else if (*nend == ':' && *(nend + 1) == ':') {
666 if ((nsplit - origname) == 5 && memEQ(origname, "SUPER", 5)) {
667 /* ->SUPER::method should really be looked up in original stash */
668 SV * const tmpstr = sv_2mortal(Perl_newSVpvf(aTHX_ "%s::SUPER",
669 CopSTASHPV(PL_curcop)));
670 /* __PACKAGE__::SUPER stash should be autovivified */
671 stash = gv_get_super_pkg(SvPVX_const(tmpstr), SvCUR(tmpstr));
672 DEBUG_o( Perl_deb(aTHX_ "Treating %s as %s::%s\n",
673 origname, HvNAME_get(stash), name) );
676 /* don't autovifify if ->NoSuchStash::method */
677 stash = gv_stashpvn(origname, nsplit - origname, 0);
679 /* however, explicit calls to Pkg::SUPER::method may
680 happen, and may require autovivification to work */
681 if (!stash && (nsplit - origname) >= 7 &&
682 strnEQ(nsplit - 7, "::SUPER", 7) &&
683 gv_stashpvn(origname, nsplit - origname - 7, 0))
684 stash = gv_get_super_pkg(origname, nsplit - origname);
689 gv = gv_fetchmeth(stash, name, nend - name, 0);
691 if (strEQ(name,"import") || strEQ(name,"unimport"))
692 gv = MUTABLE_GV(&PL_sv_yes);
694 gv = gv_autoload4(ostash, name, nend - name, TRUE);
695 if (!gv && do_croak) {
696 /* Right now this is exclusively for the benefit of S_method_common
700 "Can't locate object method \"%s\" via package \"%.*s\"",
701 name, (int)HvNAMELEN_get(stash), HvNAME_get(stash));
705 const char *packname;
708 packlen = nsplit - origname;
711 packname = SvPV_const(error_report, packlen);
715 "Can't locate object method \"%s\" via package \"%.*s\""
716 " (perhaps you forgot to load \"%.*s\"?)",
717 name, (int)packlen, packname, (int)packlen, packname);
722 CV* const cv = GvCV(gv);
723 if (!CvROOT(cv) && !CvXSUB(cv)) {
731 if (GvCV(stubgv) != cv) /* orphaned import */
734 autogv = gv_autoload4(GvSTASH(stubgv),
735 GvNAME(stubgv), GvNAMELEN(stubgv), TRUE);
745 Perl_gv_autoload4(pTHX_ HV *stash, const char *name, STRLEN len, I32 method)
753 const char *packname = "";
754 STRLEN packname_len = 0;
756 PERL_ARGS_ASSERT_GV_AUTOLOAD4;
758 if (len == S_autolen && memEQ(name, S_autoload, S_autolen))
761 if (SvTYPE(stash) < SVt_PVHV) {
762 packname = SvPV_const(MUTABLE_SV(stash), packname_len);
766 packname = HvNAME_get(stash);
767 packname_len = HvNAMELEN_get(stash);
770 if (!(gv = gv_fetchmeth(stash, S_autoload, S_autolen, FALSE)))
774 if (!(CvROOT(cv) || CvXSUB(cv)))
778 * Inheriting AUTOLOAD for non-methods works ... for now.
780 if (!method && (GvCVGEN(gv) || GvSTASH(gv) != stash)
782 Perl_ck_warner_d(aTHX_ packWARN(WARN_DEPRECATED),
783 "Use of inherited AUTOLOAD for non-method %s::%.*s() is deprecated",
784 packname, (int)len, name);
787 /* rather than lookup/init $AUTOLOAD here
788 * only to have the XSUB do another lookup for $AUTOLOAD
789 * and split that value on the last '::',
790 * pass along the same data via some unused fields in the CV
794 Perl_sv_add_backref(aTHX_ MUTABLE_SV(stash), MUTABLE_SV(cv));
795 SvPV_set(cv, (char *)name); /* cast to lose constness warning */
801 * Given &FOO::AUTOLOAD, set $FOO::AUTOLOAD to desired function name.
802 * The subroutine's original name may not be "AUTOLOAD", so we don't
803 * use that, but for lack of anything better we will use the sub's
804 * original package to look up $AUTOLOAD.
806 varstash = GvSTASH(CvGV(cv));
807 vargv = *(GV**)hv_fetch(varstash, S_autoload, S_autolen, TRUE);
811 gv_init(vargv, varstash, S_autoload, S_autolen, FALSE);
812 #ifdef PERL_DONT_CREATE_GVSV
813 GvSV(vargv) = newSV(0);
817 varsv = GvSVn(vargv);
818 sv_setpvn(varsv, packname, packname_len);
819 sv_catpvs(varsv, "::");
820 sv_catpvn(varsv, name, len);
825 /* require_tie_mod() internal routine for requiring a module
826 * that implements the logic of automatical ties like %! and %-
828 * The "gv" parameter should be the glob.
829 * "varpv" holds the name of the var, used for error messages.
830 * "namesv" holds the module name. Its refcount will be decremented.
831 * "methpv" holds the method name to test for to check that things
832 * are working reasonably close to as expected.
833 * "flags": if flag & 1 then save the scalar before loading.
834 * For the protection of $! to work (it is set by this routine)
835 * the sv slot must already be magicalized.
838 S_require_tie_mod(pTHX_ GV *gv, const char *varpv, SV* namesv, const char *methpv,const U32 flags)
841 HV* stash = gv_stashsv(namesv, 0);
843 PERL_ARGS_ASSERT_REQUIRE_TIE_MOD;
845 if (!stash || !(gv_fetchmethod(stash, methpv))) {
846 SV *module = newSVsv(namesv);
847 char varname = *varpv; /* varpv might be clobbered by load_module,
848 so save it. For the moment it's always
854 PUSHSTACKi(PERLSI_MAGIC);
855 Perl_load_module(aTHX_ PERL_LOADMOD_NOIMPORT, module, NULL);
859 stash = gv_stashsv(namesv, 0);
861 Perl_croak(aTHX_ "panic: Can't use %%%c because %"SVf" is not available",
862 varname, SVfARG(namesv));
863 else if (!gv_fetchmethod(stash, methpv))
864 Perl_croak(aTHX_ "panic: Can't use %%%c because %"SVf" does not support method %s",
865 varname, SVfARG(namesv), methpv);
867 SvREFCNT_dec(namesv);
872 =for apidoc gv_stashpv
874 Returns a pointer to the stash for a specified package. Uses C<strlen> to
875 determine the length of C<name>, then calls C<gv_stashpvn()>.
881 Perl_gv_stashpv(pTHX_ const char *name, I32 create)
883 PERL_ARGS_ASSERT_GV_STASHPV;
884 return gv_stashpvn(name, strlen(name), create);
888 =for apidoc gv_stashpvn
890 Returns a pointer to the stash for a specified package. The C<namelen>
891 parameter indicates the length of the C<name>, in bytes. C<flags> is passed
892 to C<gv_fetchpvn_flags()>, so if set to C<GV_ADD> then the package will be
893 created if it does not already exist. If the package does not exist and
894 C<flags> is 0 (or any other setting that does not create packages) then NULL
902 Perl_gv_stashpvn(pTHX_ const char *name, U32 namelen, I32 flags)
908 U32 tmplen = namelen + 2;
910 PERL_ARGS_ASSERT_GV_STASHPVN;
912 if (tmplen <= sizeof smallbuf)
915 Newx(tmpbuf, tmplen, char);
916 Copy(name, tmpbuf, namelen, char);
917 tmpbuf[namelen] = ':';
918 tmpbuf[namelen+1] = ':';
919 tmpgv = gv_fetchpvn_flags(tmpbuf, tmplen, flags, SVt_PVHV);
920 if (tmpbuf != smallbuf)
925 GvHV(tmpgv) = newHV();
927 if (!HvNAME_get(stash))
928 hv_name_set(stash, name, namelen, 0);
933 =for apidoc gv_stashsv
935 Returns a pointer to the stash for a specified package. See C<gv_stashpvn>.
941 Perl_gv_stashsv(pTHX_ SV *sv, I32 flags)
944 const char * const ptr = SvPV_const(sv,len);
946 PERL_ARGS_ASSERT_GV_STASHSV;
948 return gv_stashpvn(ptr, len, flags);
953 Perl_gv_fetchpv(pTHX_ const char *nambeg, I32 add, const svtype sv_type) {
954 PERL_ARGS_ASSERT_GV_FETCHPV;
955 return gv_fetchpvn_flags(nambeg, strlen(nambeg), add, sv_type);
959 Perl_gv_fetchsv(pTHX_ SV *name, I32 flags, const svtype sv_type) {
961 const char * const nambeg = SvPV_const(name, len);
962 PERL_ARGS_ASSERT_GV_FETCHSV;
963 return gv_fetchpvn_flags(nambeg, len, flags | SvUTF8(name), sv_type);
967 Perl_gv_fetchpvn_flags(pTHX_ const char *nambeg, STRLEN full_len, I32 flags,
968 const svtype sv_type)
971 register const char *name = nambeg;
972 register GV *gv = NULL;
975 register const char *name_cursor;
977 const I32 no_init = flags & (GV_NOADD_NOINIT | GV_NOINIT);
978 const I32 no_expand = flags & GV_NOEXPAND;
979 const I32 add = flags & ~GV_NOADD_MASK;
980 const char *const name_end = nambeg + full_len;
981 const char *const name_em1 = name_end - 1;
984 PERL_ARGS_ASSERT_GV_FETCHPVN_FLAGS;
986 if (flags & GV_NOTQUAL) {
987 /* Caller promised that there is no stash, so we can skip the check. */
992 if (full_len > 2 && *name == '*' && isALPHA(name[1])) {
993 /* accidental stringify on a GV? */
997 for (name_cursor = name; name_cursor < name_end; name_cursor++) {
998 if ((*name_cursor == ':' && name_cursor < name_em1
999 && name_cursor[1] == ':')
1000 || (*name_cursor == '\'' && name_cursor[1]))
1003 stash = PL_defstash;
1004 if (!stash || !SvREFCNT(stash)) /* symbol table under destruction */
1007 len = name_cursor - name;
1012 if (len + 2 <= (I32)sizeof (smallbuf))
1015 Newx(tmpbuf, len+2, char);
1016 Copy(name, tmpbuf, len, char);
1017 tmpbuf[len++] = ':';
1018 tmpbuf[len++] = ':';
1019 gvp = (GV**)hv_fetch(stash,tmpbuf,len,add);
1020 gv = gvp ? *gvp : NULL;
1021 if (gv && gv != (const GV *)&PL_sv_undef) {
1022 if (SvTYPE(gv) != SVt_PVGV)
1023 gv_init(gv, stash, tmpbuf, len, (add & GV_ADDMULTI));
1027 if (tmpbuf != smallbuf)
1029 if (!gv || gv == (const GV *)&PL_sv_undef)
1032 if (!(stash = GvHV(gv)))
1033 stash = GvHV(gv) = newHV();
1035 if (!HvNAME_get(stash))
1036 hv_name_set(stash, nambeg, name_cursor - nambeg, 0);
1039 if (*name_cursor == ':')
1043 if (name == name_end)
1045 ? gv : MUTABLE_GV(*hv_fetchs(PL_defstash, "main::", TRUE));
1048 len = name_cursor - name;
1050 /* No stash in name, so see how we can default */
1054 if (len && isIDFIRST_lazy(name)) {
1055 bool global = FALSE;
1063 if ((name[0] == 'I' && name[1] == 'N' && name[2] == 'C')
1064 || (name[0] == 'E' && name[1] == 'N' && name[2] == 'V')
1065 || (name[0] == 'S' && name[1] == 'I' && name[2] == 'G'))
1069 if (name[0] == 'A' && name[1] == 'R' && name[2] == 'G'
1074 if (name[0] == 'S' && name[1] == 'T' && name[2] == 'D'
1075 && name[3] == 'I' && name[4] == 'N')
1079 if ((name[0] == 'S' && name[1] == 'T' && name[2] == 'D')
1080 &&((name[3] == 'O' && name[4] == 'U' && name[5] == 'T')
1081 ||(name[3] == 'E' && name[4] == 'R' && name[5] == 'R')))
1085 if (name[0] == 'A' && name[1] == 'R' && name[2] == 'G'
1086 && name[3] == 'V' && name[4] == 'O' && name[5] == 'U'
1093 stash = PL_defstash;
1094 else if (IN_PERL_COMPILETIME) {
1095 stash = PL_curstash;
1096 if (add && (PL_hints & HINT_STRICT_VARS) &&
1097 sv_type != SVt_PVCV &&
1098 sv_type != SVt_PVGV &&
1099 sv_type != SVt_PVFM &&
1100 sv_type != SVt_PVIO &&
1101 !(len == 1 && sv_type == SVt_PV &&
1102 (*name == 'a' || *name == 'b')) )
1104 gvp = (GV**)hv_fetch(stash,name,len,0);
1106 *gvp == (const GV *)&PL_sv_undef ||
1107 SvTYPE(*gvp) != SVt_PVGV)
1111 else if ((sv_type == SVt_PV && !GvIMPORTED_SV(*gvp)) ||
1112 (sv_type == SVt_PVAV && !GvIMPORTED_AV(*gvp)) ||
1113 (sv_type == SVt_PVHV && !GvIMPORTED_HV(*gvp)) )
1115 /* diag_listed_as: Variable "%s" is not imported%s */
1117 aTHX_ packWARN(WARN_MISC),
1118 "Variable \"%c%s\" is not imported",
1119 sv_type == SVt_PVAV ? '@' :
1120 sv_type == SVt_PVHV ? '%' : '$',
1124 aTHX_ packWARN(WARN_MISC),
1125 "\t(Did you mean &%s instead?)\n", name
1132 stash = CopSTASH(PL_curcop);
1135 stash = PL_defstash;
1138 /* By this point we should have a stash and a name */
1142 SV * const err = Perl_mess(aTHX_
1143 "Global symbol \"%s%s\" requires explicit package name",
1144 (sv_type == SVt_PV ? "$"
1145 : sv_type == SVt_PVAV ? "@"
1146 : sv_type == SVt_PVHV ? "%"
1149 if (USE_UTF8_IN_NAMES)
1152 gv = gv_fetchpvs("<none>::", GV_ADDMULTI, SVt_PVHV);
1154 /* symbol table under destruction */
1163 if (!SvREFCNT(stash)) /* symbol table under destruction */
1166 gvp = (GV**)hv_fetch(stash,name,len,add);
1167 if (!gvp || *gvp == (const GV *)&PL_sv_undef)
1170 if (SvTYPE(gv) == SVt_PVGV) {
1173 gv_init_sv(gv, sv_type);
1174 if (len == 1 && (sv_type == SVt_PVHV || sv_type == SVt_PVGV)) {
1176 require_tie_mod(gv, "!", newSVpvs("Errno"), "TIEHASH", 1);
1177 else if (*name == '-' || *name == '+')
1178 require_tie_mod(gv, name, newSVpvs("Tie::Hash::NamedCapture"), "TIEHASH", 0);
1182 } else if (no_init) {
1184 } else if (no_expand && SvROK(gv)) {
1188 /* Adding a new symbol.
1189 Unless of course there was already something non-GV here, in which case
1190 we want to behave as if there was always a GV here, containing some sort
1192 Otherwise we run the risk of creating things like GvIO, which can cause
1193 subtle bugs. eg the one that tripped up SQL::Translator */
1195 faking_it = SvOK(gv);
1197 if (add & GV_ADDWARN)
1198 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL), "Had to create %s unexpectedly", nambeg);
1199 gv_init(gv, stash, name, len, add & GV_ADDMULTI);
1200 gv_init_sv(gv, faking_it ? SVt_PVCV : sv_type);
1202 if (isALPHA(name[0]) && ! (isLEXWARN_on ? ckWARN(WARN_ONCE)
1203 : (PL_dowarn & G_WARN_ON ) ) )
1206 /* set up magic where warranted */
1211 /* Nothing else to do.
1212 The compiler will probably turn the switch statement into a
1213 branch table. Make sure we avoid even that small overhead for
1214 the common case of lower case variable names. */
1218 const char * const name2 = name + 1;
1221 if (strEQ(name2, "RGV")) {
1222 IoFLAGS(GvIOn(gv)) |= IOf_ARGV|IOf_START;
1224 else if (strEQ(name2, "RGVOUT")) {
1229 if (strnEQ(name2, "XPORT", 5))
1233 if (strEQ(name2, "SA")) {
1234 AV* const av = GvAVn(gv);
1236 sv_magic(MUTABLE_SV(av), MUTABLE_SV(gv), PERL_MAGIC_isa,
1238 /* NOTE: No support for tied ISA */
1239 if ((add & GV_ADDMULTI) && strEQ(nambeg,"AnyDBM_File::ISA")
1240 && AvFILLp(av) == -1)
1242 av_push(av, newSVpvs("NDBM_File"));
1243 gv_stashpvs("NDBM_File", GV_ADD);
1244 av_push(av, newSVpvs("DB_File"));
1245 gv_stashpvs("DB_File", GV_ADD);
1246 av_push(av, newSVpvs("GDBM_File"));
1247 gv_stashpvs("GDBM_File", GV_ADD);
1248 av_push(av, newSVpvs("SDBM_File"));
1249 gv_stashpvs("SDBM_File", GV_ADD);
1250 av_push(av, newSVpvs("ODBM_File"));
1251 gv_stashpvs("ODBM_File", GV_ADD);
1256 if (strEQ(name2, "VERLOAD")) {
1257 HV* const hv = GvHVn(gv);
1259 hv_magic(hv, NULL, PERL_MAGIC_overload);
1263 if (strEQ(name2, "IG")) {
1266 if (!PL_psig_name) {
1267 Newxz(PL_psig_name, 2 * SIG_SIZE, SV*);
1268 Newxz(PL_psig_pend, SIG_SIZE, int);
1269 PL_psig_ptr = PL_psig_name + SIG_SIZE;
1271 /* I think that the only way to get here is to re-use an
1272 embedded perl interpreter, where the previous
1273 use didn't clean up fully because
1274 PL_perl_destruct_level was 0. I'm not sure that we
1275 "support" that, in that I suspect in that scenario
1276 there are sufficient other garbage values left in the
1277 interpreter structure that something else will crash
1278 before we get here. I suspect that this is one of
1279 those "doctor, it hurts when I do this" bugs. */
1280 Zero(PL_psig_name, 2 * SIG_SIZE, SV*);
1281 Zero(PL_psig_pend, SIG_SIZE, int);
1285 hv_magic(hv, NULL, PERL_MAGIC_sig);
1286 for (i = 1; i < SIG_SIZE; i++) {
1287 SV * const * const init = hv_fetch(hv, PL_sig_name[i], strlen(PL_sig_name[i]), 1);
1289 sv_setsv(*init, &PL_sv_undef);
1294 if (strEQ(name2, "ERSION"))
1297 case '\003': /* $^CHILD_ERROR_NATIVE */
1298 if (strEQ(name2, "HILD_ERROR_NATIVE"))
1301 case '\005': /* $^ENCODING */
1302 if (strEQ(name2, "NCODING"))
1305 case '\015': /* $^MATCH */
1306 if (strEQ(name2, "ATCH"))
1308 case '\017': /* $^OPEN */
1309 if (strEQ(name2, "PEN"))
1312 case '\020': /* $^PREMATCH $^POSTMATCH */
1313 if (strEQ(name2, "REMATCH") || strEQ(name2, "OSTMATCH"))
1315 case '\024': /* ${^TAINT} */
1316 if (strEQ(name2, "AINT"))
1319 case '\025': /* ${^UNICODE}, ${^UTF8LOCALE} */
1320 if (strEQ(name2, "NICODE"))
1322 if (strEQ(name2, "TF8LOCALE"))
1324 if (strEQ(name2, "TF8CACHE"))
1327 case '\027': /* $^WARNING_BITS */
1328 if (strEQ(name2, "ARNING_BITS"))
1341 /* Ensures that we have an all-digit variable, ${"1foo"} fails
1343 /* This snippet is taken from is_gv_magical */
1344 const char *end = name + len;
1345 while (--end > name) {
1346 if (!isDIGIT(*end)) return gv;
1353 /* Names of length 1. (Or 0. But name is NUL terminated, so that will
1354 be case '\0' in this switch statement (ie a default case) */
1360 sv_type == SVt_PVAV ||
1361 sv_type == SVt_PVHV ||
1362 sv_type == SVt_PVCV ||
1363 sv_type == SVt_PVFM ||
1366 PL_sawampersand = TRUE;
1370 sv_setpv(GvSVn(gv),PL_chopset);
1374 #ifdef COMPLEX_STATUS
1375 SvUPGRADE(GvSVn(gv), SVt_PVLV);
1381 /* If %! has been used, automatically load Errno.pm. */
1383 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1385 /* magicalization must be done before require_tie_mod is called */
1386 if (sv_type == SVt_PVHV || sv_type == SVt_PVGV)
1387 require_tie_mod(gv, "!", newSVpvs("Errno"), "TIEHASH", 1);
1392 GvMULTI_on(gv); /* no used once warnings here */
1394 AV* const av = GvAVn(gv);
1395 SV* const avc = (*name == '+') ? MUTABLE_SV(av) : NULL;
1397 sv_magic(MUTABLE_SV(av), avc, PERL_MAGIC_regdata, NULL, 0);
1398 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1400 SvREADONLY_on(GvSVn(gv));
1403 if (sv_type == SVt_PVHV || sv_type == SVt_PVGV)
1404 require_tie_mod(gv, name, newSVpvs("Tie::Hash::NamedCapture"), "TIEHASH", 0);
1410 if (sv_type == SVt_PV)
1411 Perl_ck_warner_d(aTHX_ packWARN2(WARN_DEPRECATED, WARN_SYNTAX),
1412 "$%c is no longer supported", *name);
1415 sv_setiv(GvSVn(gv), (IV)(IoFLAGS(GvIOp(PL_defoutgv)) & IOf_FLUSH) != 0);
1418 case '\010': /* $^H */
1420 HV *const hv = GvHVn(gv);
1421 hv_magic(hv, NULL, PERL_MAGIC_hints);
1424 case '\023': /* $^S */
1426 SvREADONLY_on(GvSVn(gv));
1450 case '\001': /* $^A */
1451 case '\003': /* $^C */
1452 case '\004': /* $^D */
1453 case '\005': /* $^E */
1454 case '\006': /* $^F */
1455 case '\011': /* $^I, NOT \t in EBCDIC */
1456 case '\016': /* $^N */
1457 case '\017': /* $^O */
1458 case '\020': /* $^P */
1459 case '\024': /* $^T */
1460 case '\027': /* $^W */
1462 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1465 case '\014': /* $^L */
1466 sv_setpvs(GvSVn(gv),"\f");
1467 PL_formfeed = GvSVn(gv);
1470 sv_setpvs(GvSVn(gv),"\034");
1474 SV * const sv = GvSVn(gv);
1475 if (!sv_derived_from(PL_patchlevel, "version"))
1476 upg_version(PL_patchlevel, TRUE);
1477 GvSV(gv) = vnumify(PL_patchlevel);
1478 SvREADONLY_on(GvSV(gv));
1482 case '\026': /* $^V */
1484 SV * const sv = GvSVn(gv);
1485 GvSV(gv) = new_version(PL_patchlevel);
1486 SvREADONLY_on(GvSV(gv));
1496 Perl_gv_fullname4(pTHX_ SV *sv, const GV *gv, const char *prefix, bool keepmain)
1500 const HV * const hv = GvSTASH(gv);
1502 PERL_ARGS_ASSERT_GV_FULLNAME4;
1508 sv_setpv(sv, prefix ? prefix : "");
1510 name = HvNAME_get(hv);
1512 namelen = HvNAMELEN_get(hv);
1518 if (keepmain || strNE(name, "main")) {
1519 sv_catpvn(sv,name,namelen);
1522 sv_catpvn(sv,GvNAME(gv),GvNAMELEN(gv));
1526 Perl_gv_efullname4(pTHX_ SV *sv, const GV *gv, const char *prefix, bool keepmain)
1528 const GV * const egv = GvEGVx(gv);
1530 PERL_ARGS_ASSERT_GV_EFULLNAME4;
1532 gv_fullname4(sv, egv ? egv : gv, prefix, keepmain);
1536 Perl_gv_check(pTHX_ const HV *stash)
1541 PERL_ARGS_ASSERT_GV_CHECK;
1543 if (!HvARRAY(stash))
1545 for (i = 0; i <= (I32) HvMAX(stash); i++) {
1547 for (entry = HvARRAY(stash)[i]; entry; entry = HeNEXT(entry)) {
1550 if (HeKEY(entry)[HeKLEN(entry)-1] == ':' &&
1551 (gv = MUTABLE_GV(HeVAL(entry))) && isGV(gv) && (hv = GvHV(gv)))
1553 if (hv != PL_defstash && hv != stash)
1554 gv_check(hv); /* nested package */
1556 else if (isALPHA(*HeKEY(entry))) {
1558 gv = MUTABLE_GV(HeVAL(entry));
1559 if (SvTYPE(gv) != SVt_PVGV || GvMULTI(gv))
1562 CopLINE_set(PL_curcop, GvLINE(gv));
1564 CopFILE(PL_curcop) = (char *)file; /* set for warning */
1566 CopFILEGV(PL_curcop)
1567 = gv_fetchfile_flags(file, HEK_LEN(GvFILE_HEK(gv)), 0);
1569 Perl_warner(aTHX_ packWARN(WARN_ONCE),
1570 "Name \"%s::%s\" used only once: possible typo",
1571 HvNAME_get(stash), GvNAME(gv));
1578 Perl_newGVgen(pTHX_ const char *pack)
1582 PERL_ARGS_ASSERT_NEWGVGEN;
1584 return gv_fetchpv(Perl_form(aTHX_ "%s::_GEN_%ld", pack, (long)PL_gensym++),
1588 /* hopefully this is only called on local symbol table entries */
1591 Perl_gp_ref(pTHX_ GP *gp)
1599 /* If the GP they asked for a reference to contains
1600 a method cache entry, clear it first, so that we
1601 don't infect them with our cached entry */
1602 SvREFCNT_dec(gp->gp_cv);
1611 Perl_gp_free(pTHX_ GV *gv)
1616 if (!gv || !isGV_with_GP(gv) || !(gp = GvGP(gv)))
1618 if (gp->gp_refcnt == 0) {
1619 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
1620 "Attempt to free unreferenced glob pointers"
1621 pTHX__FORMAT pTHX__VALUE);
1624 if (--gp->gp_refcnt > 0) {
1625 if (gp->gp_egv == gv)
1631 if (gp->gp_file_hek)
1632 unshare_hek(gp->gp_file_hek);
1633 SvREFCNT_dec(gp->gp_sv);
1634 SvREFCNT_dec(gp->gp_av);
1635 /* FIXME - another reference loop GV -> symtab -> GV ?
1636 Somehow gp->gp_hv can end up pointing at freed garbage. */
1637 if (gp->gp_hv && SvTYPE(gp->gp_hv) == SVt_PVHV) {
1638 const char *hvname = HvNAME_get(gp->gp_hv);
1639 if (PL_stashcache && hvname)
1640 (void)hv_delete(PL_stashcache, hvname, HvNAMELEN_get(gp->gp_hv),
1642 SvREFCNT_dec(gp->gp_hv);
1644 SvREFCNT_dec(gp->gp_io);
1645 SvREFCNT_dec(gp->gp_cv);
1646 SvREFCNT_dec(gp->gp_form);
1653 Perl_magic_freeovrld(pTHX_ SV *sv, MAGIC *mg)
1655 AMT * const amtp = (AMT*)mg->mg_ptr;
1656 PERL_UNUSED_ARG(sv);
1658 PERL_ARGS_ASSERT_MAGIC_FREEOVRLD;
1660 if (amtp && AMT_AMAGIC(amtp)) {
1662 for (i = 1; i < NofAMmeth; i++) {
1663 CV * const cv = amtp->table[i];
1665 SvREFCNT_dec(MUTABLE_SV(cv));
1666 amtp->table[i] = NULL;
1673 /* Updates and caches the CV's */
1675 * 1 on success and there is some overload
1676 * 0 if there is no overload
1677 * -1 if some error occurred and it couldn't croak
1681 Perl_Gv_AMupdate(pTHX_ HV *stash, bool destructing)
1684 MAGIC* const mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1686 const struct mro_meta* stash_meta = HvMROMETA(stash);
1689 PERL_ARGS_ASSERT_GV_AMUPDATE;
1691 newgen = PL_sub_generation + stash_meta->pkg_gen + stash_meta->cache_gen;
1693 const AMT * const amtp = (AMT*)mg->mg_ptr;
1694 if (amtp->was_ok_am == PL_amagic_generation
1695 && amtp->was_ok_sub == newgen) {
1696 return AMT_OVERLOADED(amtp) ? 1 : 0;
1698 sv_unmagic(MUTABLE_SV(stash), PERL_MAGIC_overload_table);
1701 DEBUG_o( Perl_deb(aTHX_ "Recalcing overload magic in package %s\n",HvNAME_get(stash)) );
1704 amt.was_ok_am = PL_amagic_generation;
1705 amt.was_ok_sub = newgen;
1706 amt.fallback = AMGfallNO;
1710 int filled = 0, have_ovl = 0;
1713 /* Work with "fallback" key, which we assume to be first in PL_AMG_names */
1715 /* Try to find via inheritance. */
1716 GV *gv = gv_fetchmeth(stash, PL_AMG_names[0], 2, -1);
1717 SV * const sv = gv ? GvSV(gv) : NULL;
1721 lim = DESTROY_amg; /* Skip overloading entries. */
1722 #ifdef PERL_DONT_CREATE_GVSV
1724 NOOP; /* Equivalent to !SvTRUE and !SvOK */
1727 else if (SvTRUE(sv))
1728 amt.fallback=AMGfallYES;
1730 amt.fallback=AMGfallNEVER;
1732 for (i = 1; i < lim; i++)
1733 amt.table[i] = NULL;
1734 for (; i < NofAMmeth; i++) {
1735 const char * const cooky = PL_AMG_names[i];
1736 /* Human-readable form, for debugging: */
1737 const char * const cp = (i >= DESTROY_amg ? cooky : AMG_id2name(i));
1738 const STRLEN l = PL_AMG_namelens[i];
1740 DEBUG_o( Perl_deb(aTHX_ "Checking overloading of \"%s\" in package \"%.256s\"\n",
1741 cp, HvNAME_get(stash)) );
1742 /* don't fill the cache while looking up!
1743 Creation of inheritance stubs in intermediate packages may
1744 conflict with the logic of runtime method substitution.
1745 Indeed, for inheritance A -> B -> C, if C overloads "+0",
1746 then we could have created stubs for "(+0" in A and C too.
1747 But if B overloads "bool", we may want to use it for
1748 numifying instead of C's "+0". */
1749 if (i >= DESTROY_amg)
1750 gv = Perl_gv_fetchmeth_autoload(aTHX_ stash, cooky, l, 0);
1751 else /* Autoload taken care of below */
1752 gv = Perl_gv_fetchmeth(aTHX_ stash, cooky, l, -1);
1754 if (gv && (cv = GvCV(gv))) {
1756 if (GvNAMELEN(CvGV(cv)) == 3 && strEQ(GvNAME(CvGV(cv)), "nil")
1757 && strEQ(hvname = HvNAME_get(GvSTASH(CvGV(cv))), "overload")) {
1758 /* This is a hack to support autoloading..., while
1759 knowing *which* methods were declared as overloaded. */
1760 /* GvSV contains the name of the method. */
1762 SV *gvsv = GvSV(gv);
1764 DEBUG_o( Perl_deb(aTHX_ "Resolving method \"%"SVf256\
1765 "\" for overloaded \"%s\" in package \"%.256s\"\n",
1766 (void*)GvSV(gv), cp, hvname) );
1767 if (!gvsv || !SvPOK(gvsv)
1768 || !(ngv = gv_fetchmethod_autoload(stash, SvPVX_const(gvsv),
1771 /* Can be an import stub (created by "can"). */
1776 const char * const name = (gvsv && SvPOK(gvsv)) ? SvPVX_const(gvsv) : "???";
1777 Perl_croak(aTHX_ "%s method \"%.256s\" overloading \"%s\" "\
1778 "in package \"%.256s\"",
1779 (GvCVGEN(gv) ? "Stub found while resolving"
1784 cv = GvCV(gv = ngv);
1786 DEBUG_o( Perl_deb(aTHX_ "Overloading \"%s\" in package \"%.256s\" via \"%.256s::%.256s\"\n",
1787 cp, HvNAME_get(stash), HvNAME_get(GvSTASH(CvGV(cv))),
1788 GvNAME(CvGV(cv))) );
1790 if (i < DESTROY_amg)
1792 } else if (gv) { /* Autoloaded... */
1793 cv = MUTABLE_CV(gv);
1796 amt.table[i]=MUTABLE_CV(SvREFCNT_inc_simple(cv));
1799 AMT_AMAGIC_on(&amt);
1801 AMT_OVERLOADED_on(&amt);
1802 sv_magic(MUTABLE_SV(stash), 0, PERL_MAGIC_overload_table,
1803 (char*)&amt, sizeof(AMT));
1807 /* Here we have no table: */
1809 AMT_AMAGIC_off(&amt);
1810 sv_magic(MUTABLE_SV(stash), 0, PERL_MAGIC_overload_table,
1811 (char*)&amt, sizeof(AMTS));
1817 Perl_gv_handler(pTHX_ HV *stash, I32 id)
1823 struct mro_meta* stash_meta;
1825 if (!stash || !HvNAME_get(stash))
1828 stash_meta = HvMROMETA(stash);
1829 newgen = PL_sub_generation + stash_meta->pkg_gen + stash_meta->cache_gen;
1831 mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1834 /* If we're looking up a destructor to invoke, we must avoid
1835 * that Gv_AMupdate croaks, because we might be dying already */
1836 if (Gv_AMupdate(stash, id == DESTROY_amg) == -1) {
1837 /* and if it didn't found a destructor, we fall back
1838 * to a simpler method that will only look for the
1839 * destructor instead of the whole magic */
1840 if (id == DESTROY_amg) {
1841 GV * const gv = gv_fetchmethod(stash, "DESTROY");
1847 mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1850 amtp = (AMT*)mg->mg_ptr;
1851 if ( amtp->was_ok_am != PL_amagic_generation
1852 || amtp->was_ok_sub != newgen )
1854 if (AMT_AMAGIC(amtp)) {
1855 CV * const ret = amtp->table[id];
1856 if (ret && isGV(ret)) { /* Autoloading stab */
1857 /* Passing it through may have resulted in a warning
1858 "Inherited AUTOLOAD for a non-method deprecated", since
1859 our caller is going through a function call, not a method call.
1860 So return the CV for AUTOLOAD, setting $AUTOLOAD. */
1861 GV * const gv = gv_fetchmethod(stash, PL_AMG_names[id]);
1873 /* Implement tryAMAGICun_MG macro.
1874 Do get magic, then see if the stack arg is overloaded and if so call it.
1876 AMGf_set return the arg using SETs rather than assigning to
1878 AMGf_numeric apply sv_2num to the stack arg.
1882 Perl_try_amagic_un(pTHX_ int method, int flags) {
1886 SV* const arg = TOPs;
1890 if (SvAMAGIC(arg) && (tmpsv = AMG_CALLun_var(arg,method))) {
1891 if (flags & AMGf_set) {
1896 if (SvPADMY(TARG)) {
1897 sv_setsv(TARG, tmpsv);
1907 if ((flags & AMGf_numeric) && SvROK(arg))
1913 /* Implement tryAMAGICbin_MG macro.
1914 Do get magic, then see if the two stack args are overloaded and if so
1917 AMGf_set return the arg using SETs rather than assigning to
1919 AMGf_assign op may be called as mutator (eg +=)
1920 AMGf_numeric apply sv_2num to the stack arg.
1924 Perl_try_amagic_bin(pTHX_ int method, int flags) {
1927 SV* const left = TOPm1s;
1928 SV* const right = TOPs;
1934 if (SvAMAGIC(left) || SvAMAGIC(right)) {
1935 SV * const tmpsv = amagic_call(left, right, method,
1936 ((flags & AMGf_assign) && opASSIGN ? AMGf_assign: 0));
1938 if (flags & AMGf_set) {
1945 if (opASSIGN || SvPADMY(TARG)) {
1946 sv_setsv(TARG, tmpsv);
1956 if (flags & AMGf_numeric) {
1958 *(sp-1) = sv_2num(left);
1960 *sp = sv_2num(right);
1967 Perl_amagic_call(pTHX_ SV *left, SV *right, int method, int flags)
1972 CV **cvp=NULL, **ocvp=NULL;
1973 AMT *amtp=NULL, *oamtp=NULL;
1974 int off = 0, off1, lr = 0, notfound = 0;
1975 int postpr = 0, force_cpy = 0;
1976 int assign = AMGf_assign & flags;
1977 const int assignshift = assign ? 1 : 0;
1983 PERL_ARGS_ASSERT_AMAGIC_CALL;
1985 if ( PL_curcop->cop_hints & HINT_NO_AMAGIC ) {
1986 SV *lex_mask = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
1987 0, "overloading", 11, 0, 0);
1989 if ( !lex_mask || !SvOK(lex_mask) )
1990 /* overloading lexically disabled */
1992 else if ( lex_mask && SvPOK(lex_mask) ) {
1993 /* we have an entry in the hints hash, check if method has been
1994 * masked by overloading.pm */
1996 const int offset = method / 8;
1997 const int bit = method % 8;
1998 char *pv = SvPV(lex_mask, len);
2000 /* Bit set, so this overloading operator is disabled */
2001 if ( (STRLEN)offset < len && pv[offset] & ( 1 << bit ) )
2006 if (!(AMGf_noleft & flags) && SvAMAGIC(left)
2007 && (stash = SvSTASH(SvRV(left)))
2008 && (mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table))
2009 && (ocvp = cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
2010 ? (oamtp = amtp = (AMT*)mg->mg_ptr)->table
2012 && ((cv = cvp[off=method+assignshift])
2013 || (assign && amtp->fallback > AMGfallNEVER && /* fallback to
2019 cv = cvp[off=method])))) {
2020 lr = -1; /* Call method for left argument */
2022 if (cvp && amtp->fallback > AMGfallNEVER && flags & AMGf_unary) {
2025 /* look for substituted methods */
2026 /* In all the covered cases we should be called with assign==0. */
2030 if ((cv = cvp[off=add_ass_amg])
2031 || ((cv = cvp[off = add_amg]) && (force_cpy = 0, postpr = 1))) {
2032 right = &PL_sv_yes; lr = -1; assign = 1;
2037 if ((cv = cvp[off = subtr_ass_amg])
2038 || ((cv = cvp[off = subtr_amg]) && (force_cpy = 0, postpr=1))) {
2039 right = &PL_sv_yes; lr = -1; assign = 1;
2043 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=string_amg]));
2046 (void)((cv = cvp[off=string_amg]) || (cv = cvp[off=bool__amg]));
2049 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=bool__amg]));
2052 (void)((cv = cvp[off=bool__amg])
2053 || (cv = cvp[off=numer_amg])
2054 || (cv = cvp[off=string_amg]));
2061 * SV* ref causes confusion with the interpreter variable of
2064 SV* const tmpRef=SvRV(left);
2065 if (!SvROK(tmpRef) && SvTYPE(tmpRef) <= SVt_PVMG) {
2067 * Just to be extra cautious. Maybe in some
2068 * additional cases sv_setsv is safe, too.
2070 SV* const newref = newSVsv(tmpRef);
2071 SvOBJECT_on(newref);
2072 /* As a bit of a source compatibility hack, SvAMAGIC() and
2073 friends dereference an RV, to behave the same was as when
2074 overloading was stored on the reference, not the referant.
2075 Hence we can't use SvAMAGIC_on()
2077 SvFLAGS(newref) |= SVf_AMAGIC;
2078 SvSTASH_set(newref, MUTABLE_HV(SvREFCNT_inc(SvSTASH(tmpRef))));
2084 if ((cvp[off1=lt_amg] || cvp[off1=ncmp_amg])
2085 && ((cv = cvp[off=neg_amg]) || (cv = cvp[off=subtr_amg]))) {
2086 SV* const nullsv=sv_2mortal(newSViv(0));
2088 SV* const lessp = amagic_call(left,nullsv,
2089 lt_amg,AMGf_noright);
2090 logic = SvTRUE(lessp);
2092 SV* const lessp = amagic_call(left,nullsv,
2093 ncmp_amg,AMGf_noright);
2094 logic = (SvNV(lessp) < 0);
2097 if (off==subtr_amg) {
2108 if ((cv = cvp[off=subtr_amg])) {
2110 left = sv_2mortal(newSViv(0));
2115 case iter_amg: /* XXXX Eventually should do to_gv. */
2116 case ftest_amg: /* XXXX Eventually should do to_gv. */
2119 return NULL; /* Delegate operation to standard mechanisms. */
2127 return left; /* Delegate operation to standard mechanisms. */
2132 if (!cv) goto not_found;
2133 } else if (!(AMGf_noright & flags) && SvAMAGIC(right)
2134 && (stash = SvSTASH(SvRV(right)))
2135 && (mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table))
2136 && (cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
2137 ? (amtp = (AMT*)mg->mg_ptr)->table
2139 && (cv = cvp[off=method])) { /* Method for right
2142 } else if (((ocvp && oamtp->fallback > AMGfallNEVER
2143 && (cvp=ocvp) && (lr = -1))
2144 || (cvp && amtp->fallback > AMGfallNEVER && (lr=1)))
2145 && !(flags & AMGf_unary)) {
2146 /* We look for substitution for
2147 * comparison operations and
2149 if (method==concat_amg || method==concat_ass_amg
2150 || method==repeat_amg || method==repeat_ass_amg) {
2151 return NULL; /* Delegate operation to string conversion */
2172 if ((off != -1) && (cv = cvp[off]))
2177 not_found: /* No method found, either report or croak */
2185 return left; /* Delegate operation to standard mechanisms. */
2188 if (ocvp && (cv=ocvp[nomethod_amg])) { /* Call report method */
2189 notfound = 1; lr = -1;
2190 } else if (cvp && (cv=cvp[nomethod_amg])) {
2191 notfound = 1; lr = 1;
2192 } else if ((amtp && amtp->fallback >= AMGfallYES) && !DEBUG_o_TEST) {
2193 /* Skip generating the "no method found" message. */
2197 if (off==-1) off=method;
2198 msg = sv_2mortal(Perl_newSVpvf(aTHX_
2199 "Operation \"%s\": no method found,%sargument %s%s%s%s",
2200 AMG_id2name(method + assignshift),
2201 (flags & AMGf_unary ? " " : "\n\tleft "),
2203 "in overloaded package ":
2204 "has no overloaded magic",
2206 HvNAME_get(SvSTASH(SvRV(left))):
2209 ",\n\tright argument in overloaded package ":
2212 : ",\n\tright argument has no overloaded magic"),
2214 HvNAME_get(SvSTASH(SvRV(right))):
2216 if (amtp && amtp->fallback >= AMGfallYES) {
2217 DEBUG_o( Perl_deb(aTHX_ "%s", SvPVX_const(msg)) );
2219 Perl_croak(aTHX_ "%"SVf, SVfARG(msg));
2223 force_cpy = force_cpy || assign;
2228 DEBUG_o(Perl_deb(aTHX_
2229 "Overloaded operator \"%s\"%s%s%s:\n\tmethod%s found%s in package %s%s\n",
2231 method+assignshift==off? "" :
2233 method+assignshift==off? "" :
2234 AMG_id2name(method+assignshift),
2235 method+assignshift==off? "" : "\")",
2236 flags & AMGf_unary? "" :
2237 lr==1 ? " for right argument": " for left argument",
2238 flags & AMGf_unary? " for argument" : "",
2239 stash ? HvNAME_get(stash) : "null",
2240 fl? ",\n\tassignment variant used": "") );
2243 /* Since we use shallow copy during assignment, we need
2244 * to dublicate the contents, probably calling user-supplied
2245 * version of copy operator
2247 /* We need to copy in following cases:
2248 * a) Assignment form was called.
2249 * assignshift==1, assign==T, method + 1 == off
2250 * b) Increment or decrement, called directly.
2251 * assignshift==0, assign==0, method + 0 == off
2252 * c) Increment or decrement, translated to assignment add/subtr.
2253 * assignshift==0, assign==T,
2255 * d) Increment or decrement, translated to nomethod.
2256 * assignshift==0, assign==0,
2258 * e) Assignment form translated to nomethod.
2259 * assignshift==1, assign==T, method + 1 != off
2262 /* off is method, method+assignshift, or a result of opcode substitution.
2263 * In the latter case assignshift==0, so only notfound case is important.
2265 if (( (method + assignshift == off)
2266 && (assign || (method == inc_amg) || (method == dec_amg)))
2276 const bool oldcatch = CATCH_GET;
2279 Zero(&myop, 1, BINOP);
2280 myop.op_last = (OP *) &myop;
2281 myop.op_next = NULL;
2282 myop.op_flags = OPf_WANT_SCALAR | OPf_STACKED;
2284 PUSHSTACKi(PERLSI_OVERLOAD);
2287 PL_op = (OP *) &myop;
2288 if (PERLDB_SUB && PL_curstash != PL_debstash)
2289 PL_op->op_private |= OPpENTERSUB_DB;
2293 EXTEND(SP, notfound + 5);
2294 PUSHs(lr>0? right: left);
2295 PUSHs(lr>0? left: right);
2296 PUSHs( lr > 0 ? &PL_sv_yes : ( assign ? &PL_sv_undef : &PL_sv_no ));
2298 PUSHs(newSVpvn_flags(AMG_id2name(method + assignshift),
2299 AMG_id2namelen(method + assignshift), SVs_TEMP));
2301 PUSHs(MUTABLE_SV(cv));
2304 if ((PL_op = PL_ppaddr[OP_ENTERSUB](aTHX)))
2312 CATCH_SET(oldcatch);
2319 ans=SvIV(res)<=0; break;
2322 ans=SvIV(res)<0; break;
2325 ans=SvIV(res)>=0; break;
2328 ans=SvIV(res)>0; break;
2331 ans=SvIV(res)==0; break;
2334 ans=SvIV(res)!=0; break;
2337 SvSetSV(left,res); return left;
2339 ans=!SvTRUE(res); break;
2344 } else if (method==copy_amg) {
2346 Perl_croak(aTHX_ "Copy method did not return a reference");
2348 return SvREFCNT_inc(SvRV(res));
2356 =for apidoc is_gv_magical_sv
2358 Returns C<TRUE> if given the name of a magical GV.
2360 Currently only useful internally when determining if a GV should be
2361 created even in rvalue contexts.
2363 C<flags> is not used at present but available for future extension to
2364 allow selecting particular classes of magical variable.
2366 Currently assumes that C<name> is NUL terminated (as well as len being valid).
2367 This assumption is met by all callers within the perl core, which all pass
2368 pointers returned by SvPV.
2374 Perl_is_gv_magical_sv(pTHX_ SV *const name_sv, U32 flags)
2377 const char *const name = SvPV_const(name_sv, len);
2379 PERL_UNUSED_ARG(flags);
2380 PERL_ARGS_ASSERT_IS_GV_MAGICAL_SV;
2383 const char * const name1 = name + 1;
2386 if (len == 3 && name[1] == 'S' && name[2] == 'A')
2390 if (len == 8 && strEQ(name1, "VERLOAD"))
2394 if (len == 3 && name[1] == 'I' && name[2] == 'G')
2397 /* Using ${^...} variables is likely to be sufficiently rare that
2398 it seems sensible to avoid the space hit of also checking the
2400 case '\017': /* ${^OPEN} */
2401 if (strEQ(name1, "PEN"))
2404 case '\024': /* ${^TAINT} */
2405 if (strEQ(name1, "AINT"))
2408 case '\025': /* ${^UNICODE} */
2409 if (strEQ(name1, "NICODE"))
2411 if (strEQ(name1, "TF8LOCALE"))
2414 case '\027': /* ${^WARNING_BITS} */
2415 if (strEQ(name1, "ARNING_BITS"))
2428 const char *end = name + len;
2429 while (--end > name) {
2437 /* Because we're already assuming that name is NUL terminated
2438 below, we can treat an empty name as "\0" */
2464 case '\001': /* $^A */
2465 case '\003': /* $^C */
2466 case '\004': /* $^D */
2467 case '\005': /* $^E */
2468 case '\006': /* $^F */
2469 case '\010': /* $^H */
2470 case '\011': /* $^I, NOT \t in EBCDIC */
2471 case '\014': /* $^L */
2472 case '\016': /* $^N */
2473 case '\017': /* $^O */
2474 case '\020': /* $^P */
2475 case '\023': /* $^S */
2476 case '\024': /* $^T */
2477 case '\026': /* $^V */
2478 case '\027': /* $^W */
2498 Perl_gv_name_set(pTHX_ GV *gv, const char *name, U32 len, U32 flags)
2503 PERL_ARGS_ASSERT_GV_NAME_SET;
2504 PERL_UNUSED_ARG(flags);
2507 Perl_croak(aTHX_ "panic: gv name too long (%"UVuf")", (UV) len);
2509 if (!(flags & GV_ADD) && GvNAME_HEK(gv)) {
2510 unshare_hek(GvNAME_HEK(gv));
2513 PERL_HASH(hash, name, len);
2514 GvNAME_HEK(gv) = share_hek(name, len, hash);
2518 =for apidoc gv_try_downgrade
2520 If the typeglob C<gv> can be expressed more succinctly, by having
2521 something other than a real GV in its place in the stash, replace it
2522 with the optimised form. Basic requirements for this are that C<gv>
2523 is a real typeglob, is sufficiently ordinary, and is only referenced
2524 from its package. This function is meant to be used when a GV has been
2525 looked up in part to see what was there, causing upgrading, but based
2526 on what was found it turns out that the real GV isn't required after all.
2528 If C<gv> is a completely empty typeglob, it is deleted from the stash.
2530 If C<gv> is a typeglob containing only a sufficiently-ordinary constant
2531 sub, the typeglob is replaced with a scalar-reference placeholder that
2532 more compactly represents the same thing.
2538 Perl_gv_try_downgrade(pTHX_ GV *gv)
2544 PERL_ARGS_ASSERT_GV_TRY_DOWNGRADE;
2545 if (!(SvREFCNT(gv) == 1 && SvTYPE(gv) == SVt_PVGV && !SvFAKE(gv) &&
2546 !SvOBJECT(gv) && !SvREADONLY(gv) &&
2547 isGV_with_GP(gv) && GvGP(gv) &&
2548 !GvINTRO(gv) && GvREFCNT(gv) == 1 &&
2549 !GvSV(gv) && !GvAV(gv) && !GvHV(gv) && !GvIOp(gv) && !GvFORM(gv) &&
2550 GvEGVx(gv) == gv && (stash = GvSTASH(gv))))
2552 if (SvMAGICAL(gv)) {
2554 /* only backref magic is allowed */
2555 if (SvGMAGICAL(gv) || SvSMAGICAL(gv))
2557 for (mg = SvMAGIC(gv); mg; mg = mg->mg_moremagic) {
2558 if (mg->mg_type != PERL_MAGIC_backref)
2564 HEK *gvnhek = GvNAME_HEK(gv);
2565 (void)hv_delete(stash, HEK_KEY(gvnhek),
2566 HEK_UTF8(gvnhek) ? -HEK_LEN(gvnhek) : HEK_LEN(gvnhek), G_DISCARD);
2567 } else if (GvMULTI(gv) && cv &&
2568 !SvOBJECT(cv) && !SvMAGICAL(cv) && !SvREADONLY(cv) &&
2569 CvSTASH(cv) == stash && CvGV(cv) == gv &&
2570 CvCONST(cv) && !CvMETHOD(cv) && !CvLVALUE(cv) && !CvUNIQUE(cv) &&
2571 !CvNODEBUG(cv) && !CvCLONE(cv) && !CvCLONED(cv) && !CvANON(cv) &&
2572 (namehek = GvNAME_HEK(gv)) &&
2573 (gvp = hv_fetch(stash, HEK_KEY(namehek),
2574 HEK_LEN(namehek)*(HEK_UTF8(namehek) ? -1 : 1), 0)) &&
2576 SV *value = SvREFCNT_inc(CvXSUBANY(cv).any_ptr);
2580 SvFLAGS(gv) = SVt_IV|SVf_ROK;
2581 SvANY(gv) = (XPVGV*)((char*)&(gv->sv_u.svu_iv) -
2582 STRUCT_OFFSET(XPVIV, xiv_iv));
2583 SvRV_set(gv, value);
2589 * c-indentation-style: bsd
2591 * indent-tabs-mode: t
2594 * ex: set ts=8 sts=4 sw=4 noet: