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 $foo, @foo, %foo.
29 GVs are usually found as values in stashes (symbol table hashes) where
30 Perl stores its global variables.
40 static const char S_autoload[] = "AUTOLOAD";
41 static const STRLEN S_autolen = sizeof(S_autoload)-1;
44 Perl_gv_add_by_type(pTHX_ GV *gv, svtype type)
51 SvTYPE((const SV *)gv) != SVt_PVGV
52 && SvTYPE((const SV *)gv) != SVt_PVLV
56 if (type == SVt_PVIO) {
58 * if it walks like a dirhandle, then let's assume that
59 * this is a dirhandle.
61 what = PL_op->op_type == OP_READDIR ||
62 PL_op->op_type == OP_TELLDIR ||
63 PL_op->op_type == OP_SEEKDIR ||
64 PL_op->op_type == OP_REWINDDIR ||
65 PL_op->op_type == OP_CLOSEDIR ?
66 "dirhandle" : "filehandle";
67 /* diag_listed_as: Bad symbol for filehandle */
68 } else if (type == SVt_PVHV) {
71 what = type == SVt_PVAV ? "array" : "scalar";
73 Perl_croak(aTHX_ "Bad symbol for %s", what);
76 if (type == SVt_PVHV) {
77 where = (SV **)&GvHV(gv);
78 } else if (type == SVt_PVAV) {
79 where = (SV **)&GvAV(gv);
80 } else if (type == SVt_PVIO) {
81 where = (SV **)&GvIOp(gv);
87 *where = newSV_type(type);
92 Perl_gv_fetchfile(pTHX_ const char *name)
94 PERL_ARGS_ASSERT_GV_FETCHFILE;
95 return gv_fetchfile_flags(name, strlen(name), 0);
99 Perl_gv_fetchfile_flags(pTHX_ const char *const name, const STRLEN namelen,
105 const STRLEN tmplen = namelen + 2;
108 PERL_ARGS_ASSERT_GV_FETCHFILE_FLAGS;
109 PERL_UNUSED_ARG(flags);
114 if (tmplen <= sizeof smallbuf)
117 Newx(tmpbuf, tmplen, char);
118 /* This is where the debugger's %{"::_<$filename"} hash is created */
121 memcpy(tmpbuf + 2, name, namelen);
122 gv = *(GV**)hv_fetch(PL_defstash, tmpbuf, tmplen, TRUE);
124 gv_init(gv, PL_defstash, tmpbuf, tmplen, FALSE);
125 #ifdef PERL_DONT_CREATE_GVSV
126 GvSV(gv) = newSVpvn(name, namelen);
128 sv_setpvn(GvSV(gv), name, namelen);
131 if ((PERLDB_LINE || PERLDB_SAVESRC) && !GvAV(gv))
132 hv_magic(GvHVn(gv_AVadd(gv)), NULL, PERL_MAGIC_dbfile);
133 if (tmpbuf != smallbuf)
139 =for apidoc gv_const_sv
141 If C<gv> is a typeglob whose subroutine entry is a constant sub eligible for
142 inlining, or C<gv> is a placeholder reference that would be promoted to such
143 a typeglob, then returns the value returned by the sub. Otherwise, returns
150 Perl_gv_const_sv(pTHX_ GV *gv)
152 PERL_ARGS_ASSERT_GV_CONST_SV;
154 if (SvTYPE(gv) == SVt_PVGV)
155 return cv_const_sv(GvCVu(gv));
156 return SvROK(gv) ? SvRV(gv) : NULL;
160 Perl_newGP(pTHX_ GV *const gv)
165 const char *const file
166 = (PL_curcop && CopFILE(PL_curcop)) ? CopFILE(PL_curcop) : "";
167 const STRLEN len = strlen(file);
169 SV *const temp_sv = CopFILESV(PL_curcop);
173 PERL_ARGS_ASSERT_NEWGP;
176 file = SvPVX(temp_sv);
177 len = SvCUR(temp_sv);
184 PERL_HASH(hash, file, len);
188 #ifndef PERL_DONT_CREATE_GVSV
189 gp->gp_sv = newSV(0);
192 gp->gp_line = PL_curcop ? CopLINE(PL_curcop) : 0;
193 /* XXX Ideally this cast would be replaced with a change to const char*
195 gp->gp_file_hek = share_hek(file, len, hash);
202 /* Assign CvGV(cv) = gv, handling weak references.
203 * See also S_anonymise_cv_maybe */
206 Perl_cvgv_set(pTHX_ CV* cv, GV* gv)
208 GV * const oldgv = CvGV(cv);
209 PERL_ARGS_ASSERT_CVGV_SET;
220 sv_del_backref(MUTABLE_SV(oldgv), MUTABLE_SV(cv));
224 SvANY(cv)->xcv_gv = gv;
225 assert(!CvCVGV_RC(cv));
230 if (isGV_with_GP(gv) && GvGP(gv) && (GvCV(gv) == cv || GvFORM(gv) == cv))
231 Perl_sv_add_backref(aTHX_ MUTABLE_SV(gv), MUTABLE_SV(cv));
234 SvREFCNT_inc_simple_void_NN(gv);
238 /* Assign CvSTASH(cv) = st, handling weak references. */
241 Perl_cvstash_set(pTHX_ CV *cv, HV *st)
243 HV *oldst = CvSTASH(cv);
244 PERL_ARGS_ASSERT_CVSTASH_SET;
248 sv_del_backref(MUTABLE_SV(oldst), MUTABLE_SV(cv));
249 SvANY(cv)->xcv_stash = st;
251 Perl_sv_add_backref(aTHX_ MUTABLE_SV(st), MUTABLE_SV(cv));
255 Perl_gv_init(pTHX_ GV *gv, HV *stash, const char *name, STRLEN len, int multi)
258 const U32 old_type = SvTYPE(gv);
259 const bool doproto = old_type > SVt_NULL;
260 char * const proto = (doproto && SvPOK(gv)) ? SvPVX(gv) : NULL;
261 const STRLEN protolen = proto ? SvCUR(gv) : 0;
262 SV *const has_constant = doproto && SvROK(gv) ? SvRV(gv) : NULL;
263 const U32 exported_constant = has_constant ? SvPCS_IMPORTED(gv) : 0;
265 PERL_ARGS_ASSERT_GV_INIT;
266 assert (!(proto && has_constant));
269 /* The constant has to be a simple scalar type. */
270 switch (SvTYPE(has_constant)) {
276 Perl_croak(aTHX_ "Cannot convert a reference to %s to typeglob",
277 sv_reftype(has_constant, 0));
285 if (old_type < SVt_PVGV) {
286 if (old_type >= SVt_PV)
288 sv_upgrade(MUTABLE_SV(gv), SVt_PVGV);
296 Safefree(SvPVX_mutable(gv));
301 GvGP(gv) = Perl_newGP(aTHX_ gv);
304 Perl_sv_add_backref(aTHX_ MUTABLE_SV(stash), MUTABLE_SV(gv));
305 gv_name_set(gv, name, len, GV_ADD);
306 if (multi || doproto) /* doproto means it _was_ mentioned */
308 if (doproto) { /* Replicate part of newSUB here. */
314 /* newCONSTSUB doesn't take a len arg, so make sure we
315 * give it a \0-terminated string */
316 name0 = savepvn(name,len);
318 /* newCONSTSUB takes ownership of the reference from us. */
319 cv = newCONSTSUB(stash, (name0 ? name0 : name), has_constant);
320 assert(GvCV(gv) == cv); /* newCONSTSUB should have set this */
323 /* If this reference was a copy of another, then the subroutine
324 must have been "imported", by a Perl space assignment to a GV
325 from a reference to CV. */
326 if (exported_constant)
327 GvIMPORTED_CV_on(gv);
329 (void) start_subparse(0,0); /* Create empty CV in compcv. */
335 mro_method_changed_in(GvSTASH(gv)); /* sub Foo::bar($) { (shift) } sub ASDF::baz($); *ASDF::baz = \&Foo::bar */
337 CvFILE_set_from_cop(cv, PL_curcop);
338 CvSTASH_set(cv, PL_curstash);
340 sv_usepvn_flags(MUTABLE_SV(cv), proto, protolen,
341 SV_HAS_TRAILING_NUL);
347 S_gv_init_sv(pTHX_ GV *gv, const svtype sv_type)
349 PERL_ARGS_ASSERT_GV_INIT_SV;
361 #ifdef PERL_DONT_CREATE_GVSV
369 /* Work round what appears to be a bug in Sun C++ 5.8 2005/10/13
370 If we just cast GvSVn(gv) to void, it ignores evaluating it for
378 =for apidoc gv_fetchmeth
380 Returns the glob with the given C<name> and a defined subroutine or
381 C<NULL>. The glob lives in the given C<stash>, or in the stashes
382 accessible via @ISA and UNIVERSAL::.
384 The argument C<level> should be either 0 or -1. If C<level==0>, as a
385 side-effect creates a glob with the given C<name> in the given C<stash>
386 which in the case of success contains an alias for the subroutine, and sets
387 up caching info for this glob.
389 This function grants C<"SUPER"> token as a postfix of the stash name. The
390 GV returned from C<gv_fetchmeth> may be a method cache entry, which is not
391 visible to Perl code. So when calling C<call_sv>, you should not use
392 the GV directly; instead, you should use the method's CV, which can be
393 obtained from the GV with the C<GvCV> macro.
398 /* NOTE: No support for tied ISA */
401 Perl_gv_fetchmeth(pTHX_ HV *stash, const char *name, STRLEN len, I32 level)
409 GV* candidate = NULL;
414 I32 create = (level >= 0) ? 1 : 0;
419 PERL_ARGS_ASSERT_GV_FETCHMETH;
421 /* UNIVERSAL methods should be callable without a stash */
423 create = 0; /* probably appropriate */
424 if(!(stash = gv_stashpvs("UNIVERSAL", 0)))
430 hvname = HvNAME_get(stash);
432 Perl_croak(aTHX_ "Can't use anonymous symbol table for method lookup");
437 DEBUG_o( Perl_deb(aTHX_ "Looking for method %s in package %s\n",name,hvname) );
439 topgen_cmp = HvMROMETA(stash)->cache_gen + PL_sub_generation;
441 /* check locally for a real method or a cache entry */
442 gvp = (GV**)hv_fetch(stash, name, len, create);
446 if (SvTYPE(topgv) != SVt_PVGV)
447 gv_init(topgv, stash, name, len, TRUE);
448 if ((cand_cv = GvCV(topgv))) {
449 /* If genuine method or valid cache entry, use it */
450 if (!GvCVGEN(topgv) || GvCVGEN(topgv) == topgen_cmp) {
454 /* stale cache entry, junk it and move on */
455 SvREFCNT_dec(cand_cv);
456 GvCV(topgv) = cand_cv = NULL;
460 else if (GvCVGEN(topgv) == topgen_cmp) {
461 /* cache indicates no such method definitively */
466 packlen = HvNAMELEN_get(stash);
467 if (packlen >= 7 && strEQ(hvname + packlen - 7, "::SUPER")) {
470 basestash = gv_stashpvn(hvname, packlen, GV_ADD);
471 linear_av = mro_get_linear_isa(basestash);
474 linear_av = mro_get_linear_isa(stash); /* has ourselves at the top of the list */
477 linear_svp = AvARRAY(linear_av) + 1; /* skip over self */
478 items = AvFILLp(linear_av); /* no +1, to skip over self */
480 linear_sv = *linear_svp++;
482 cstash = gv_stashsv(linear_sv, 0);
485 Perl_ck_warner(aTHX_ packWARN(WARN_SYNTAX), "Can't locate package %"SVf" for @%s::ISA",
486 SVfARG(linear_sv), hvname);
492 gvp = (GV**)hv_fetch(cstash, name, len, 0);
496 if (SvTYPE(candidate) != SVt_PVGV) gv_init(candidate, cstash, name, len, TRUE);
497 if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
499 * Found real method, cache method in topgv if:
500 * 1. topgv has no synonyms (else inheritance crosses wires)
501 * 2. method isn't a stub (else AUTOLOAD fails spectacularly)
503 if (topgv && (GvREFCNT(topgv) == 1) && (CvROOT(cand_cv) || CvXSUB(cand_cv))) {
504 if ((old_cv = GvCV(topgv))) SvREFCNT_dec(old_cv);
505 SvREFCNT_inc_simple_void_NN(cand_cv);
506 GvCV(topgv) = cand_cv;
507 GvCVGEN(topgv) = topgen_cmp;
513 /* Check UNIVERSAL without caching */
514 if(level == 0 || level == -1) {
515 candidate = gv_fetchmeth(NULL, name, len, 1);
517 cand_cv = GvCV(candidate);
518 if (topgv && (GvREFCNT(topgv) == 1) && (CvROOT(cand_cv) || CvXSUB(cand_cv))) {
519 if ((old_cv = GvCV(topgv))) SvREFCNT_dec(old_cv);
520 SvREFCNT_inc_simple_void_NN(cand_cv);
521 GvCV(topgv) = cand_cv;
522 GvCVGEN(topgv) = topgen_cmp;
528 if (topgv && GvREFCNT(topgv) == 1) {
529 /* cache the fact that the method is not defined */
530 GvCVGEN(topgv) = topgen_cmp;
537 =for apidoc gv_fetchmeth_autoload
539 Same as gv_fetchmeth(), but looks for autoloaded subroutines too.
540 Returns a glob for the subroutine.
542 For an autoloaded subroutine without a GV, will create a GV even
543 if C<level < 0>. For an autoloaded subroutine without a stub, GvCV()
544 of the result may be zero.
550 Perl_gv_fetchmeth_autoload(pTHX_ HV *stash, const char *name, STRLEN len, I32 level)
552 GV *gv = gv_fetchmeth(stash, name, len, level);
554 PERL_ARGS_ASSERT_GV_FETCHMETH_AUTOLOAD;
561 return NULL; /* UNIVERSAL::AUTOLOAD could cause trouble */
562 if (len == S_autolen && memEQ(name, S_autoload, S_autolen))
564 if (!(gv = gv_fetchmeth(stash, S_autoload, S_autolen, FALSE)))
567 if (!(CvROOT(cv) || CvXSUB(cv)))
569 /* Have an autoload */
570 if (level < 0) /* Cannot do without a stub */
571 gv_fetchmeth(stash, name, len, 0);
572 gvp = (GV**)hv_fetch(stash, name, len, (level >= 0));
581 =for apidoc gv_fetchmethod_autoload
583 Returns the glob which contains the subroutine to call to invoke the method
584 on the C<stash>. In fact in the presence of autoloading this may be the
585 glob for "AUTOLOAD". In this case the corresponding variable $AUTOLOAD is
588 The third parameter of C<gv_fetchmethod_autoload> determines whether
589 AUTOLOAD lookup is performed if the given method is not present: non-zero
590 means yes, look for AUTOLOAD; zero means no, don't look for AUTOLOAD.
591 Calling C<gv_fetchmethod> is equivalent to calling C<gv_fetchmethod_autoload>
592 with a non-zero C<autoload> parameter.
594 These functions grant C<"SUPER"> token as a prefix of the method name. Note
595 that if you want to keep the returned glob for a long time, you need to
596 check for it being "AUTOLOAD", since at the later time the call may load a
597 different subroutine due to $AUTOLOAD changing its value. Use the glob
598 created via a side effect to do this.
600 These functions have the same side-effects and as C<gv_fetchmeth> with
601 C<level==0>. C<name> should be writable if contains C<':'> or C<'
602 ''>. The warning against passing the GV returned by C<gv_fetchmeth> to
603 C<call_sv> apply equally to these functions.
609 S_gv_get_super_pkg(pTHX_ const char* name, I32 namelen)
616 PERL_ARGS_ASSERT_GV_GET_SUPER_PKG;
618 stash = gv_stashpvn(name, namelen, 0);
619 if(stash) return stash;
621 /* If we must create it, give it an @ISA array containing
622 the real package this SUPER is for, so that it's tied
623 into the cache invalidation code correctly */
624 stash = gv_stashpvn(name, namelen, GV_ADD);
625 gvp = (GV**)hv_fetchs(stash, "ISA", TRUE);
627 gv_init(gv, stash, "ISA", 3, TRUE);
628 superisa = GvAVn(gv);
630 sv_magic(MUTABLE_SV(superisa), MUTABLE_SV(gv), PERL_MAGIC_isa, NULL, 0);
632 av_push(superisa, newSVpv(CopSTASHPV(PL_curcop), 0));
634 av_push(superisa, newSVhek(CopSTASH(PL_curcop)
635 ? HvNAME_HEK(CopSTASH(PL_curcop)) : NULL));
642 Perl_gv_fetchmethod_autoload(pTHX_ HV *stash, const char *name, I32 autoload)
644 PERL_ARGS_ASSERT_GV_FETCHMETHOD_AUTOLOAD;
646 return gv_fetchmethod_flags(stash, name, autoload ? GV_AUTOLOAD : 0);
649 /* Don't merge this yet, as it's likely to get a len parameter, and possibly
652 Perl_gv_fetchmethod_flags(pTHX_ HV *stash, const char *name, U32 flags)
655 register const char *nend;
656 const char *nsplit = NULL;
659 const char * const origname = name;
660 SV *const error_report = MUTABLE_SV(stash);
661 const U32 autoload = flags & GV_AUTOLOAD;
662 const U32 do_croak = flags & GV_CROAK;
664 PERL_ARGS_ASSERT_GV_FETCHMETHOD_FLAGS;
666 if (SvTYPE(stash) < SVt_PVHV)
669 /* The only way stash can become NULL later on is if nsplit is set,
670 which in turn means that there is no need for a SVt_PVHV case
671 the error reporting code. */
674 for (nend = name; *nend; nend++) {
679 else if (*nend == ':' && *(nend + 1) == ':') {
685 if ((nsplit - origname) == 5 && memEQ(origname, "SUPER", 5)) {
686 /* ->SUPER::method should really be looked up in original stash */
687 SV * const tmpstr = sv_2mortal(Perl_newSVpvf(aTHX_ "%s::SUPER",
688 CopSTASHPV(PL_curcop)));
689 /* __PACKAGE__::SUPER stash should be autovivified */
690 stash = gv_get_super_pkg(SvPVX_const(tmpstr), SvCUR(tmpstr));
691 DEBUG_o( Perl_deb(aTHX_ "Treating %s as %s::%s\n",
692 origname, HvNAME_get(stash), name) );
695 /* don't autovifify if ->NoSuchStash::method */
696 stash = gv_stashpvn(origname, nsplit - origname, 0);
698 /* however, explicit calls to Pkg::SUPER::method may
699 happen, and may require autovivification to work */
700 if (!stash && (nsplit - origname) >= 7 &&
701 strnEQ(nsplit - 7, "::SUPER", 7) &&
702 gv_stashpvn(origname, nsplit - origname - 7, 0))
703 stash = gv_get_super_pkg(origname, nsplit - origname);
708 gv = gv_fetchmeth(stash, name, nend - name, 0);
710 if (strEQ(name,"import") || strEQ(name,"unimport"))
711 gv = MUTABLE_GV(&PL_sv_yes);
713 gv = gv_autoload4(ostash, name, nend - name, TRUE);
714 if (!gv && do_croak) {
715 /* Right now this is exclusively for the benefit of S_method_common
719 "Can't locate object method \"%s\" via package \"%.*s\"",
720 name, (int)HvNAMELEN_get(stash), HvNAME_get(stash));
724 const char *packname;
727 packlen = nsplit - origname;
730 packname = SvPV_const(error_report, packlen);
734 "Can't locate object method \"%s\" via package \"%.*s\""
735 " (perhaps you forgot to load \"%.*s\"?)",
736 name, (int)packlen, packname, (int)packlen, packname);
741 CV* const cv = GvCV(gv);
742 if (!CvROOT(cv) && !CvXSUB(cv)) {
750 if (GvCV(stubgv) != cv) /* orphaned import */
753 autogv = gv_autoload4(GvSTASH(stubgv),
754 GvNAME(stubgv), GvNAMELEN(stubgv), TRUE);
764 Perl_gv_autoload4(pTHX_ HV *stash, const char *name, STRLEN len, I32 method)
772 const char *packname = "";
773 STRLEN packname_len = 0;
775 PERL_ARGS_ASSERT_GV_AUTOLOAD4;
777 if (len == S_autolen && memEQ(name, S_autoload, S_autolen))
780 if (SvTYPE(stash) < SVt_PVHV) {
781 packname = SvPV_const(MUTABLE_SV(stash), packname_len);
785 packname = HvNAME_get(stash);
786 packname_len = HvNAMELEN_get(stash);
789 if (!(gv = gv_fetchmeth(stash, S_autoload, S_autolen, FALSE)))
793 if (!(CvROOT(cv) || CvXSUB(cv)))
797 * Inheriting AUTOLOAD for non-methods works ... for now.
799 if (!method && (GvCVGEN(gv) || GvSTASH(gv) != stash)
801 Perl_ck_warner_d(aTHX_ packWARN(WARN_DEPRECATED),
802 "Use of inherited AUTOLOAD for non-method %s::%.*s() is deprecated",
803 packname, (int)len, name);
806 /* rather than lookup/init $AUTOLOAD here
807 * only to have the XSUB do another lookup for $AUTOLOAD
808 * and split that value on the last '::',
809 * pass along the same data via some unused fields in the CV
811 CvSTASH_set(cv, stash);
812 SvPV_set(cv, (char *)name); /* cast to lose constness warning */
818 * Given &FOO::AUTOLOAD, set $FOO::AUTOLOAD to desired function name.
819 * The subroutine's original name may not be "AUTOLOAD", so we don't
820 * use that, but for lack of anything better we will use the sub's
821 * original package to look up $AUTOLOAD.
823 varstash = GvSTASH(CvGV(cv));
824 vargv = *(GV**)hv_fetch(varstash, S_autoload, S_autolen, TRUE);
828 gv_init(vargv, varstash, S_autoload, S_autolen, FALSE);
829 #ifdef PERL_DONT_CREATE_GVSV
830 GvSV(vargv) = newSV(0);
834 varsv = GvSVn(vargv);
835 sv_setpvn(varsv, packname, packname_len);
836 sv_catpvs(varsv, "::");
837 sv_catpvn(varsv, name, len);
842 /* require_tie_mod() internal routine for requiring a module
843 * that implements the logic of automatical ties like %! and %-
845 * The "gv" parameter should be the glob.
846 * "varpv" holds the name of the var, used for error messages.
847 * "namesv" holds the module name. Its refcount will be decremented.
848 * "methpv" holds the method name to test for to check that things
849 * are working reasonably close to as expected.
850 * "flags": if flag & 1 then save the scalar before loading.
851 * For the protection of $! to work (it is set by this routine)
852 * the sv slot must already be magicalized.
855 S_require_tie_mod(pTHX_ GV *gv, const char *varpv, SV* namesv, const char *methpv,const U32 flags)
858 HV* stash = gv_stashsv(namesv, 0);
860 PERL_ARGS_ASSERT_REQUIRE_TIE_MOD;
862 if (!stash || !(gv_fetchmethod(stash, methpv))) {
863 SV *module = newSVsv(namesv);
864 char varname = *varpv; /* varpv might be clobbered by load_module,
865 so save it. For the moment it's always
871 PUSHSTACKi(PERLSI_MAGIC);
872 Perl_load_module(aTHX_ PERL_LOADMOD_NOIMPORT, module, NULL);
876 stash = gv_stashsv(namesv, 0);
878 Perl_croak(aTHX_ "panic: Can't use %%%c because %"SVf" is not available",
879 varname, SVfARG(namesv));
880 else if (!gv_fetchmethod(stash, methpv))
881 Perl_croak(aTHX_ "panic: Can't use %%%c because %"SVf" does not support method %s",
882 varname, SVfARG(namesv), methpv);
884 SvREFCNT_dec(namesv);
889 =for apidoc gv_stashpv
891 Returns a pointer to the stash for a specified package. Uses C<strlen> to
892 determine the length of C<name>, then calls C<gv_stashpvn()>.
898 Perl_gv_stashpv(pTHX_ const char *name, I32 create)
900 PERL_ARGS_ASSERT_GV_STASHPV;
901 return gv_stashpvn(name, strlen(name), create);
905 =for apidoc gv_stashpvn
907 Returns a pointer to the stash for a specified package. The C<namelen>
908 parameter indicates the length of the C<name>, in bytes. C<flags> is passed
909 to C<gv_fetchpvn_flags()>, so if set to C<GV_ADD> then the package will be
910 created if it does not already exist. If the package does not exist and
911 C<flags> is 0 (or any other setting that does not create packages) then NULL
919 Perl_gv_stashpvn(pTHX_ const char *name, U32 namelen, I32 flags)
925 U32 tmplen = namelen + 2;
927 PERL_ARGS_ASSERT_GV_STASHPVN;
929 if (tmplen <= sizeof smallbuf)
932 Newx(tmpbuf, tmplen, char);
933 Copy(name, tmpbuf, namelen, char);
934 tmpbuf[namelen] = ':';
935 tmpbuf[namelen+1] = ':';
936 tmpgv = gv_fetchpvn_flags(tmpbuf, tmplen, flags, SVt_PVHV);
937 if (tmpbuf != smallbuf)
943 assert(HvNAME_get(stash));
948 =for apidoc gv_stashsv
950 Returns a pointer to the stash for a specified package. See C<gv_stashpvn>.
956 Perl_gv_stashsv(pTHX_ SV *sv, I32 flags)
959 const char * const ptr = SvPV_const(sv,len);
961 PERL_ARGS_ASSERT_GV_STASHSV;
963 return gv_stashpvn(ptr, len, flags);
968 Perl_gv_fetchpv(pTHX_ const char *nambeg, I32 add, const svtype sv_type) {
969 PERL_ARGS_ASSERT_GV_FETCHPV;
970 return gv_fetchpvn_flags(nambeg, strlen(nambeg), add, sv_type);
974 Perl_gv_fetchsv(pTHX_ SV *name, I32 flags, const svtype sv_type) {
976 const char * const nambeg = SvPV_const(name, len);
977 PERL_ARGS_ASSERT_GV_FETCHSV;
978 return gv_fetchpvn_flags(nambeg, len, flags | SvUTF8(name), sv_type);
982 S_gv_magicalize_isa(pTHX_ GV *gv)
986 PERL_ARGS_ASSERT_GV_MAGICALIZE_ISA;
990 sv_magic(MUTABLE_SV(av), MUTABLE_SV(gv), PERL_MAGIC_isa,
995 S_gv_magicalize_overload(pTHX_ GV *gv)
999 PERL_ARGS_ASSERT_GV_MAGICALIZE_OVERLOAD;
1003 hv_magic(hv, NULL, PERL_MAGIC_overload);
1007 Perl_gv_fetchpvn_flags(pTHX_ const char *nambeg, STRLEN full_len, I32 flags,
1008 const svtype sv_type)
1011 register const char *name = nambeg;
1012 register GV *gv = NULL;
1015 register const char *name_cursor;
1017 const I32 no_init = flags & (GV_NOADD_NOINIT | GV_NOINIT);
1018 const I32 no_expand = flags & GV_NOEXPAND;
1019 const I32 add = flags & ~GV_NOADD_MASK;
1020 const char *const name_end = nambeg + full_len;
1021 const char *const name_em1 = name_end - 1;
1024 PERL_ARGS_ASSERT_GV_FETCHPVN_FLAGS;
1026 if (flags & GV_NOTQUAL) {
1027 /* Caller promised that there is no stash, so we can skip the check. */
1032 if (full_len > 2 && *name == '*' && isALPHA(name[1])) {
1033 /* accidental stringify on a GV? */
1037 for (name_cursor = name; name_cursor < name_end; name_cursor++) {
1038 if ((*name_cursor == ':' && name_cursor < name_em1
1039 && name_cursor[1] == ':')
1040 || (*name_cursor == '\'' && name_cursor[1]))
1043 stash = PL_defstash;
1044 if (!stash || !SvREFCNT(stash)) /* symbol table under destruction */
1047 len = name_cursor - name;
1050 if (*name_cursor == ':') {
1055 Newx(tmpbuf, len+2, char);
1056 Copy(name, tmpbuf, len, char);
1057 tmpbuf[len++] = ':';
1058 tmpbuf[len++] = ':';
1061 gvp = (GV**)hv_fetch(stash, key, len, add);
1062 gv = gvp ? *gvp : NULL;
1063 if (gv && gv != (const GV *)&PL_sv_undef) {
1064 if (SvTYPE(gv) != SVt_PVGV)
1065 gv_init(gv, stash, key, len, (add & GV_ADDMULTI));
1070 Safefree((char *)key);
1071 if (!gv || gv == (const GV *)&PL_sv_undef)
1074 if (!(stash = GvHV(gv)))
1075 stash = GvHV(gv) = newHV();
1077 if (!HvNAME_get(stash))
1078 hv_name_set(stash, nambeg, name_cursor - nambeg, 0);
1081 if (*name_cursor == ':')
1085 if (name == name_end)
1087 ? gv : MUTABLE_GV(*hv_fetchs(PL_defstash, "main::", TRUE));
1090 len = name_cursor - name;
1092 /* No stash in name, so see how we can default */
1096 if (len && isIDFIRST_lazy(name)) {
1097 bool global = FALSE;
1105 if ((name[0] == 'I' && name[1] == 'N' && name[2] == 'C')
1106 || (name[0] == 'E' && name[1] == 'N' && name[2] == 'V')
1107 || (name[0] == 'S' && name[1] == 'I' && name[2] == 'G'))
1111 if (name[0] == 'A' && name[1] == 'R' && name[2] == 'G'
1116 if (name[0] == 'S' && name[1] == 'T' && name[2] == 'D'
1117 && name[3] == 'I' && name[4] == 'N')
1121 if ((name[0] == 'S' && name[1] == 'T' && name[2] == 'D')
1122 &&((name[3] == 'O' && name[4] == 'U' && name[5] == 'T')
1123 ||(name[3] == 'E' && name[4] == 'R' && name[5] == 'R')))
1127 if (name[0] == 'A' && name[1] == 'R' && name[2] == 'G'
1128 && name[3] == 'V' && name[4] == 'O' && name[5] == 'U'
1135 stash = PL_defstash;
1136 else if (IN_PERL_COMPILETIME) {
1137 stash = PL_curstash;
1138 if (add && (PL_hints & HINT_STRICT_VARS) &&
1139 sv_type != SVt_PVCV &&
1140 sv_type != SVt_PVGV &&
1141 sv_type != SVt_PVFM &&
1142 sv_type != SVt_PVIO &&
1143 !(len == 1 && sv_type == SVt_PV &&
1144 (*name == 'a' || *name == 'b')) )
1146 gvp = (GV**)hv_fetch(stash,name,len,0);
1148 *gvp == (const GV *)&PL_sv_undef ||
1149 SvTYPE(*gvp) != SVt_PVGV)
1153 else if ((sv_type == SVt_PV && !GvIMPORTED_SV(*gvp)) ||
1154 (sv_type == SVt_PVAV && !GvIMPORTED_AV(*gvp)) ||
1155 (sv_type == SVt_PVHV && !GvIMPORTED_HV(*gvp)) )
1157 /* diag_listed_as: Variable "%s" is not imported%s */
1159 aTHX_ packWARN(WARN_MISC),
1160 "Variable \"%c%s\" is not imported",
1161 sv_type == SVt_PVAV ? '@' :
1162 sv_type == SVt_PVHV ? '%' : '$',
1166 aTHX_ packWARN(WARN_MISC),
1167 "\t(Did you mean &%s instead?)\n", name
1174 stash = CopSTASH(PL_curcop);
1177 stash = PL_defstash;
1180 /* By this point we should have a stash and a name */
1184 SV * const err = Perl_mess(aTHX_
1185 "Global symbol \"%s%s\" requires explicit package name",
1186 (sv_type == SVt_PV ? "$"
1187 : sv_type == SVt_PVAV ? "@"
1188 : sv_type == SVt_PVHV ? "%"
1191 if (USE_UTF8_IN_NAMES)
1194 gv = gv_fetchpvs("<none>::", GV_ADDMULTI, SVt_PVHV);
1196 /* symbol table under destruction */
1205 if (!SvREFCNT(stash)) /* symbol table under destruction */
1208 gvp = (GV**)hv_fetch(stash,name,len,add);
1209 if (!gvp || *gvp == (const GV *)&PL_sv_undef)
1212 if (SvTYPE(gv) == SVt_PVGV) {
1215 gv_init_sv(gv, sv_type);
1216 if (len == 1 && (sv_type == SVt_PVHV || sv_type == SVt_PVGV)) {
1218 require_tie_mod(gv, "!", newSVpvs("Errno"), "TIEHASH", 1);
1219 else if (*name == '-' || *name == '+')
1220 require_tie_mod(gv, name, newSVpvs("Tie::Hash::NamedCapture"), "TIEHASH", 0);
1224 } else if (no_init) {
1226 } else if (no_expand && SvROK(gv)) {
1230 /* Adding a new symbol.
1231 Unless of course there was already something non-GV here, in which case
1232 we want to behave as if there was always a GV here, containing some sort
1234 Otherwise we run the risk of creating things like GvIO, which can cause
1235 subtle bugs. eg the one that tripped up SQL::Translator */
1237 faking_it = SvOK(gv);
1239 if (add & GV_ADDWARN)
1240 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL), "Had to create %s unexpectedly", nambeg);
1241 gv_init(gv, stash, name, len, add & GV_ADDMULTI);
1242 gv_init_sv(gv, faking_it ? SVt_PVCV : sv_type);
1244 if (isALPHA(name[0]) && ! (isLEXWARN_on ? ckWARN(WARN_ONCE)
1245 : (PL_dowarn & G_WARN_ON ) ) )
1248 /* set up magic where warranted */
1249 if (stash != PL_defstash) { /* not the main stash */
1250 /* We only have to check for four names here: EXPORT, ISA, OVERLOAD
1251 and VERSION. All the others apply only to the main stash. */
1253 const char * const name2 = name + 1;
1256 if (strnEQ(name2, "XPORT", 5))
1260 if (strEQ(name2, "SA"))
1261 gv_magicalize_isa(gv);
1264 if (strEQ(name2, "VERLOAD"))
1265 gv_magicalize_overload(gv);
1268 if (strEQ(name2, "ERSION"))
1278 /* Nothing else to do.
1279 The compiler will probably turn the switch statement into a
1280 branch table. Make sure we avoid even that small overhead for
1281 the common case of lower case variable names. */
1285 const char * const name2 = name + 1;
1288 if (strEQ(name2, "RGV")) {
1289 IoFLAGS(GvIOn(gv)) |= IOf_ARGV|IOf_START;
1291 else if (strEQ(name2, "RGVOUT")) {
1296 if (strnEQ(name2, "XPORT", 5))
1300 if (strEQ(name2, "SA")) {
1301 gv_magicalize_isa(gv);
1305 if (strEQ(name2, "VERLOAD")) {
1306 gv_magicalize_overload(gv);
1310 if (strEQ(name2, "IG")) {
1313 if (!PL_psig_name) {
1314 Newxz(PL_psig_name, 2 * SIG_SIZE, SV*);
1315 Newxz(PL_psig_pend, SIG_SIZE, int);
1316 PL_psig_ptr = PL_psig_name + SIG_SIZE;
1318 /* I think that the only way to get here is to re-use an
1319 embedded perl interpreter, where the previous
1320 use didn't clean up fully because
1321 PL_perl_destruct_level was 0. I'm not sure that we
1322 "support" that, in that I suspect in that scenario
1323 there are sufficient other garbage values left in the
1324 interpreter structure that something else will crash
1325 before we get here. I suspect that this is one of
1326 those "doctor, it hurts when I do this" bugs. */
1327 Zero(PL_psig_name, 2 * SIG_SIZE, SV*);
1328 Zero(PL_psig_pend, SIG_SIZE, int);
1332 hv_magic(hv, NULL, PERL_MAGIC_sig);
1333 for (i = 1; i < SIG_SIZE; i++) {
1334 SV * const * const init = hv_fetch(hv, PL_sig_name[i], strlen(PL_sig_name[i]), 1);
1336 sv_setsv(*init, &PL_sv_undef);
1341 if (strEQ(name2, "ERSION"))
1344 case '\003': /* $^CHILD_ERROR_NATIVE */
1345 if (strEQ(name2, "HILD_ERROR_NATIVE"))
1348 case '\005': /* $^ENCODING */
1349 if (strEQ(name2, "NCODING"))
1352 case '\015': /* $^MATCH */
1353 if (strEQ(name2, "ATCH"))
1355 case '\017': /* $^OPEN */
1356 if (strEQ(name2, "PEN"))
1359 case '\020': /* $^PREMATCH $^POSTMATCH */
1360 if (strEQ(name2, "REMATCH") || strEQ(name2, "OSTMATCH"))
1362 case '\024': /* ${^TAINT} */
1363 if (strEQ(name2, "AINT"))
1366 case '\025': /* ${^UNICODE}, ${^UTF8LOCALE} */
1367 if (strEQ(name2, "NICODE"))
1369 if (strEQ(name2, "TF8LOCALE"))
1371 if (strEQ(name2, "TF8CACHE"))
1374 case '\027': /* $^WARNING_BITS */
1375 if (strEQ(name2, "ARNING_BITS"))
1388 /* Ensures that we have an all-digit variable, ${"1foo"} fails
1390 /* This snippet is taken from is_gv_magical */
1391 const char *end = name + len;
1392 while (--end > name) {
1393 if (!isDIGIT(*end)) return gv;
1400 /* Names of length 1. (Or 0. But name is NUL terminated, so that will
1401 be case '\0' in this switch statement (ie a default case) */
1407 sv_type == SVt_PVAV ||
1408 sv_type == SVt_PVHV ||
1409 sv_type == SVt_PVCV ||
1410 sv_type == SVt_PVFM ||
1413 PL_sawampersand = TRUE;
1417 sv_setpv(GvSVn(gv),PL_chopset);
1421 #ifdef COMPLEX_STATUS
1422 SvUPGRADE(GvSVn(gv), SVt_PVLV);
1428 /* If %! has been used, automatically load Errno.pm. */
1430 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1432 /* magicalization must be done before require_tie_mod is called */
1433 if (sv_type == SVt_PVHV || sv_type == SVt_PVGV)
1434 require_tie_mod(gv, "!", newSVpvs("Errno"), "TIEHASH", 1);
1439 GvMULTI_on(gv); /* no used once warnings here */
1441 AV* const av = GvAVn(gv);
1442 SV* const avc = (*name == '+') ? MUTABLE_SV(av) : NULL;
1444 sv_magic(MUTABLE_SV(av), avc, PERL_MAGIC_regdata, NULL, 0);
1445 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1447 SvREADONLY_on(GvSVn(gv));
1450 if (sv_type == SVt_PVHV || sv_type == SVt_PVGV)
1451 require_tie_mod(gv, name, newSVpvs("Tie::Hash::NamedCapture"), "TIEHASH", 0);
1457 if (sv_type == SVt_PV)
1458 Perl_ck_warner_d(aTHX_ packWARN2(WARN_DEPRECATED, WARN_SYNTAX),
1459 "$%c is no longer supported", *name);
1462 sv_setiv(GvSVn(gv), (IV)(IoFLAGS(GvIOp(PL_defoutgv)) & IOf_FLUSH) != 0);
1465 case '\010': /* $^H */
1467 HV *const hv = GvHVn(gv);
1468 hv_magic(hv, NULL, PERL_MAGIC_hints);
1471 case '\023': /* $^S */
1473 SvREADONLY_on(GvSVn(gv));
1497 case '\001': /* $^A */
1498 case '\003': /* $^C */
1499 case '\004': /* $^D */
1500 case '\005': /* $^E */
1501 case '\006': /* $^F */
1502 case '\011': /* $^I, NOT \t in EBCDIC */
1503 case '\016': /* $^N */
1504 case '\017': /* $^O */
1505 case '\020': /* $^P */
1506 case '\024': /* $^T */
1507 case '\027': /* $^W */
1509 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1512 case '\014': /* $^L */
1513 sv_setpvs(GvSVn(gv),"\f");
1514 PL_formfeed = GvSVn(gv);
1517 sv_setpvs(GvSVn(gv),"\034");
1521 SV * const sv = GvSVn(gv);
1522 if (!sv_derived_from(PL_patchlevel, "version"))
1523 upg_version(PL_patchlevel, TRUE);
1524 GvSV(gv) = vnumify(PL_patchlevel);
1525 SvREADONLY_on(GvSV(gv));
1529 case '\026': /* $^V */
1531 SV * const sv = GvSVn(gv);
1532 GvSV(gv) = new_version(PL_patchlevel);
1533 SvREADONLY_on(GvSV(gv));
1543 Perl_gv_fullname4(pTHX_ SV *sv, const GV *gv, const char *prefix, bool keepmain)
1547 const HV * const hv = GvSTASH(gv);
1549 PERL_ARGS_ASSERT_GV_FULLNAME4;
1555 sv_setpv(sv, prefix ? prefix : "");
1557 name = HvNAME_get(hv);
1559 namelen = HvNAMELEN_get(hv);
1565 if (keepmain || strNE(name, "main")) {
1566 sv_catpvn(sv,name,namelen);
1569 sv_catpvn(sv,GvNAME(gv),GvNAMELEN(gv));
1573 Perl_gv_efullname4(pTHX_ SV *sv, const GV *gv, const char *prefix, bool keepmain)
1575 const GV * const egv = GvEGVx(gv);
1577 PERL_ARGS_ASSERT_GV_EFULLNAME4;
1579 gv_fullname4(sv, egv ? egv : gv, prefix, keepmain);
1583 Perl_gv_check(pTHX_ const HV *stash)
1588 PERL_ARGS_ASSERT_GV_CHECK;
1590 if (!HvARRAY(stash))
1592 for (i = 0; i <= (I32) HvMAX(stash); i++) {
1594 for (entry = HvARRAY(stash)[i]; entry; entry = HeNEXT(entry)) {
1597 if (HeKEY(entry)[HeKLEN(entry)-1] == ':' &&
1598 (gv = MUTABLE_GV(HeVAL(entry))) && isGV(gv) && (hv = GvHV(gv)))
1600 if (hv != PL_defstash && hv != stash)
1601 gv_check(hv); /* nested package */
1603 else if (isALPHA(*HeKEY(entry))) {
1605 gv = MUTABLE_GV(HeVAL(entry));
1606 if (SvTYPE(gv) != SVt_PVGV || GvMULTI(gv))
1609 CopLINE_set(PL_curcop, GvLINE(gv));
1611 CopFILE(PL_curcop) = (char *)file; /* set for warning */
1613 CopFILEGV(PL_curcop)
1614 = gv_fetchfile_flags(file, HEK_LEN(GvFILE_HEK(gv)), 0);
1616 Perl_warner(aTHX_ packWARN(WARN_ONCE),
1617 "Name \"%s::%s\" used only once: possible typo",
1618 HvNAME_get(stash), GvNAME(gv));
1625 Perl_newGVgen(pTHX_ const char *pack)
1629 PERL_ARGS_ASSERT_NEWGVGEN;
1631 return gv_fetchpv(Perl_form(aTHX_ "%s::_GEN_%ld", pack, (long)PL_gensym++),
1635 /* hopefully this is only called on local symbol table entries */
1638 Perl_gp_ref(pTHX_ GP *gp)
1646 /* If the GP they asked for a reference to contains
1647 a method cache entry, clear it first, so that we
1648 don't infect them with our cached entry */
1649 SvREFCNT_dec(gp->gp_cv);
1658 Perl_gp_free(pTHX_ GV *gv)
1663 if (!gv || !isGV_with_GP(gv) || !(gp = GvGP(gv)))
1665 if (gp->gp_refcnt == 0) {
1666 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
1667 "Attempt to free unreferenced glob pointers"
1668 pTHX__FORMAT pTHX__VALUE);
1671 if (--gp->gp_refcnt > 0) {
1672 if (gp->gp_egv == gv)
1678 if (gp->gp_file_hek)
1679 unshare_hek(gp->gp_file_hek);
1680 SvREFCNT_dec(gp->gp_sv);
1681 SvREFCNT_dec(gp->gp_av);
1682 /* FIXME - another reference loop GV -> symtab -> GV ?
1683 Somehow gp->gp_hv can end up pointing at freed garbage. */
1684 if (gp->gp_hv && SvTYPE(gp->gp_hv) == SVt_PVHV) {
1685 const char *hvname = HvNAME_get(gp->gp_hv);
1686 if (PL_stashcache && hvname)
1687 (void)hv_delete(PL_stashcache, hvname, HvNAMELEN_get(gp->gp_hv),
1689 SvREFCNT_dec(gp->gp_hv);
1691 SvREFCNT_dec(gp->gp_io);
1692 SvREFCNT_dec(gp->gp_cv);
1693 SvREFCNT_dec(gp->gp_form);
1700 Perl_magic_freeovrld(pTHX_ SV *sv, MAGIC *mg)
1702 AMT * const amtp = (AMT*)mg->mg_ptr;
1703 PERL_UNUSED_ARG(sv);
1705 PERL_ARGS_ASSERT_MAGIC_FREEOVRLD;
1707 if (amtp && AMT_AMAGIC(amtp)) {
1709 for (i = 1; i < NofAMmeth; i++) {
1710 CV * const cv = amtp->table[i];
1712 SvREFCNT_dec(MUTABLE_SV(cv));
1713 amtp->table[i] = NULL;
1720 /* Updates and caches the CV's */
1722 * 1 on success and there is some overload
1723 * 0 if there is no overload
1724 * -1 if some error occurred and it couldn't croak
1728 Perl_Gv_AMupdate(pTHX_ HV *stash, bool destructing)
1731 MAGIC* const mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1733 const struct mro_meta* stash_meta = HvMROMETA(stash);
1736 PERL_ARGS_ASSERT_GV_AMUPDATE;
1738 newgen = PL_sub_generation + stash_meta->pkg_gen + stash_meta->cache_gen;
1740 const AMT * const amtp = (AMT*)mg->mg_ptr;
1741 if (amtp->was_ok_am == PL_amagic_generation
1742 && amtp->was_ok_sub == newgen) {
1743 return AMT_OVERLOADED(amtp) ? 1 : 0;
1745 sv_unmagic(MUTABLE_SV(stash), PERL_MAGIC_overload_table);
1748 DEBUG_o( Perl_deb(aTHX_ "Recalcing overload magic in package %s\n",HvNAME_get(stash)) );
1751 amt.was_ok_am = PL_amagic_generation;
1752 amt.was_ok_sub = newgen;
1753 amt.fallback = AMGfallNO;
1757 int filled = 0, have_ovl = 0;
1760 /* Work with "fallback" key, which we assume to be first in PL_AMG_names */
1762 /* Try to find via inheritance. */
1763 GV *gv = gv_fetchmeth(stash, PL_AMG_names[0], 2, -1);
1764 SV * const sv = gv ? GvSV(gv) : NULL;
1768 lim = DESTROY_amg; /* Skip overloading entries. */
1769 #ifdef PERL_DONT_CREATE_GVSV
1771 NOOP; /* Equivalent to !SvTRUE and !SvOK */
1774 else if (SvTRUE(sv))
1775 amt.fallback=AMGfallYES;
1777 amt.fallback=AMGfallNEVER;
1779 for (i = 1; i < lim; i++)
1780 amt.table[i] = NULL;
1781 for (; i < NofAMmeth; i++) {
1782 const char * const cooky = PL_AMG_names[i];
1783 /* Human-readable form, for debugging: */
1784 const char * const cp = (i >= DESTROY_amg ? cooky : AMG_id2name(i));
1785 const STRLEN l = PL_AMG_namelens[i];
1787 DEBUG_o( Perl_deb(aTHX_ "Checking overloading of \"%s\" in package \"%.256s\"\n",
1788 cp, HvNAME_get(stash)) );
1789 /* don't fill the cache while looking up!
1790 Creation of inheritance stubs in intermediate packages may
1791 conflict with the logic of runtime method substitution.
1792 Indeed, for inheritance A -> B -> C, if C overloads "+0",
1793 then we could have created stubs for "(+0" in A and C too.
1794 But if B overloads "bool", we may want to use it for
1795 numifying instead of C's "+0". */
1796 if (i >= DESTROY_amg)
1797 gv = Perl_gv_fetchmeth_autoload(aTHX_ stash, cooky, l, 0);
1798 else /* Autoload taken care of below */
1799 gv = Perl_gv_fetchmeth(aTHX_ stash, cooky, l, -1);
1801 if (gv && (cv = GvCV(gv))) {
1803 if (GvNAMELEN(CvGV(cv)) == 3 && strEQ(GvNAME(CvGV(cv)), "nil")
1804 && strEQ(hvname = HvNAME_get(GvSTASH(CvGV(cv))), "overload")) {
1805 /* This is a hack to support autoloading..., while
1806 knowing *which* methods were declared as overloaded. */
1807 /* GvSV contains the name of the method. */
1809 SV *gvsv = GvSV(gv);
1811 DEBUG_o( Perl_deb(aTHX_ "Resolving method \"%"SVf256\
1812 "\" for overloaded \"%s\" in package \"%.256s\"\n",
1813 (void*)GvSV(gv), cp, hvname) );
1814 if (!gvsv || !SvPOK(gvsv)
1815 || !(ngv = gv_fetchmethod_autoload(stash, SvPVX_const(gvsv),
1818 /* Can be an import stub (created by "can"). */
1823 const char * const name = (gvsv && SvPOK(gvsv)) ? SvPVX_const(gvsv) : "???";
1824 Perl_croak(aTHX_ "%s method \"%.256s\" overloading \"%s\" "\
1825 "in package \"%.256s\"",
1826 (GvCVGEN(gv) ? "Stub found while resolving"
1831 cv = GvCV(gv = ngv);
1833 DEBUG_o( Perl_deb(aTHX_ "Overloading \"%s\" in package \"%.256s\" via \"%.256s::%.256s\"\n",
1834 cp, HvNAME_get(stash), HvNAME_get(GvSTASH(CvGV(cv))),
1835 GvNAME(CvGV(cv))) );
1837 if (i < DESTROY_amg)
1839 } else if (gv) { /* Autoloaded... */
1840 cv = MUTABLE_CV(gv);
1843 amt.table[i]=MUTABLE_CV(SvREFCNT_inc_simple(cv));
1846 AMT_AMAGIC_on(&amt);
1848 AMT_OVERLOADED_on(&amt);
1849 sv_magic(MUTABLE_SV(stash), 0, PERL_MAGIC_overload_table,
1850 (char*)&amt, sizeof(AMT));
1854 /* Here we have no table: */
1856 AMT_AMAGIC_off(&amt);
1857 sv_magic(MUTABLE_SV(stash), 0, PERL_MAGIC_overload_table,
1858 (char*)&amt, sizeof(AMTS));
1864 Perl_gv_handler(pTHX_ HV *stash, I32 id)
1870 struct mro_meta* stash_meta;
1872 if (!stash || !HvNAME_get(stash))
1875 stash_meta = HvMROMETA(stash);
1876 newgen = PL_sub_generation + stash_meta->pkg_gen + stash_meta->cache_gen;
1878 mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1881 /* If we're looking up a destructor to invoke, we must avoid
1882 * that Gv_AMupdate croaks, because we might be dying already */
1883 if (Gv_AMupdate(stash, id == DESTROY_amg) == -1) {
1884 /* and if it didn't found a destructor, we fall back
1885 * to a simpler method that will only look for the
1886 * destructor instead of the whole magic */
1887 if (id == DESTROY_amg) {
1888 GV * const gv = gv_fetchmethod(stash, "DESTROY");
1894 mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1897 amtp = (AMT*)mg->mg_ptr;
1898 if ( amtp->was_ok_am != PL_amagic_generation
1899 || amtp->was_ok_sub != newgen )
1901 if (AMT_AMAGIC(amtp)) {
1902 CV * const ret = amtp->table[id];
1903 if (ret && isGV(ret)) { /* Autoloading stab */
1904 /* Passing it through may have resulted in a warning
1905 "Inherited AUTOLOAD for a non-method deprecated", since
1906 our caller is going through a function call, not a method call.
1907 So return the CV for AUTOLOAD, setting $AUTOLOAD. */
1908 GV * const gv = gv_fetchmethod(stash, PL_AMG_names[id]);
1920 /* Implement tryAMAGICun_MG macro.
1921 Do get magic, then see if the stack arg is overloaded and if so call it.
1923 AMGf_set return the arg using SETs rather than assigning to
1925 AMGf_numeric apply sv_2num to the stack arg.
1929 Perl_try_amagic_un(pTHX_ int method, int flags) {
1933 SV* const arg = TOPs;
1937 if (SvAMAGIC(arg) && (tmpsv = AMG_CALLun_var(arg,method))) {
1938 if (flags & AMGf_set) {
1943 if (SvPADMY(TARG)) {
1944 sv_setsv(TARG, tmpsv);
1954 if ((flags & AMGf_numeric) && SvROK(arg))
1960 /* Implement tryAMAGICbin_MG macro.
1961 Do get magic, then see if the two stack args are overloaded and if so
1964 AMGf_set return the arg using SETs rather than assigning to
1966 AMGf_assign op may be called as mutator (eg +=)
1967 AMGf_numeric apply sv_2num to the stack arg.
1971 Perl_try_amagic_bin(pTHX_ int method, int flags) {
1974 SV* const left = TOPm1s;
1975 SV* const right = TOPs;
1981 if (SvAMAGIC(left) || SvAMAGIC(right)) {
1982 SV * const tmpsv = amagic_call(left, right, method,
1983 ((flags & AMGf_assign) && opASSIGN ? AMGf_assign: 0));
1985 if (flags & AMGf_set) {
1992 if (opASSIGN || SvPADMY(TARG)) {
1993 sv_setsv(TARG, tmpsv);
2003 if (flags & AMGf_numeric) {
2005 *(sp-1) = sv_2num(left);
2007 *sp = sv_2num(right);
2014 Perl_amagic_call(pTHX_ SV *left, SV *right, int method, int flags)
2019 CV **cvp=NULL, **ocvp=NULL;
2020 AMT *amtp=NULL, *oamtp=NULL;
2021 int off = 0, off1, lr = 0, notfound = 0;
2022 int postpr = 0, force_cpy = 0;
2023 int assign = AMGf_assign & flags;
2024 const int assignshift = assign ? 1 : 0;
2030 PERL_ARGS_ASSERT_AMAGIC_CALL;
2032 if ( PL_curcop->cop_hints & HINT_NO_AMAGIC ) {
2033 SV *lex_mask = cop_hints_fetch_pvs(PL_curcop, "overloading", 0);
2035 if ( !lex_mask || !SvOK(lex_mask) )
2036 /* overloading lexically disabled */
2038 else if ( lex_mask && SvPOK(lex_mask) ) {
2039 /* we have an entry in the hints hash, check if method has been
2040 * masked by overloading.pm */
2042 const int offset = method / 8;
2043 const int bit = method % 8;
2044 char *pv = SvPV(lex_mask, len);
2046 /* Bit set, so this overloading operator is disabled */
2047 if ( (STRLEN)offset < len && pv[offset] & ( 1 << bit ) )
2052 if (!(AMGf_noleft & flags) && SvAMAGIC(left)
2053 && (stash = SvSTASH(SvRV(left)))
2054 && (mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table))
2055 && (ocvp = cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
2056 ? (oamtp = amtp = (AMT*)mg->mg_ptr)->table
2058 && ((cv = cvp[off=method+assignshift])
2059 || (assign && amtp->fallback > AMGfallNEVER && /* fallback to
2065 cv = cvp[off=method])))) {
2066 lr = -1; /* Call method for left argument */
2068 if (cvp && amtp->fallback > AMGfallNEVER && flags & AMGf_unary) {
2071 /* look for substituted methods */
2072 /* In all the covered cases we should be called with assign==0. */
2076 if ((cv = cvp[off=add_ass_amg])
2077 || ((cv = cvp[off = add_amg]) && (force_cpy = 0, postpr = 1))) {
2078 right = &PL_sv_yes; lr = -1; assign = 1;
2083 if ((cv = cvp[off = subtr_ass_amg])
2084 || ((cv = cvp[off = subtr_amg]) && (force_cpy = 0, postpr=1))) {
2085 right = &PL_sv_yes; lr = -1; assign = 1;
2089 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=string_amg]));
2092 (void)((cv = cvp[off=string_amg]) || (cv = cvp[off=bool__amg]));
2095 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=bool__amg]));
2098 (void)((cv = cvp[off=bool__amg])
2099 || (cv = cvp[off=numer_amg])
2100 || (cv = cvp[off=string_amg]));
2107 * SV* ref causes confusion with the interpreter variable of
2110 SV* const tmpRef=SvRV(left);
2111 if (!SvROK(tmpRef) && SvTYPE(tmpRef) <= SVt_PVMG) {
2113 * Just to be extra cautious. Maybe in some
2114 * additional cases sv_setsv is safe, too.
2116 SV* const newref = newSVsv(tmpRef);
2117 SvOBJECT_on(newref);
2118 /* As a bit of a source compatibility hack, SvAMAGIC() and
2119 friends dereference an RV, to behave the same was as when
2120 overloading was stored on the reference, not the referant.
2121 Hence we can't use SvAMAGIC_on()
2123 SvFLAGS(newref) |= SVf_AMAGIC;
2124 SvSTASH_set(newref, MUTABLE_HV(SvREFCNT_inc(SvSTASH(tmpRef))));
2130 if ((cvp[off1=lt_amg] || cvp[off1=ncmp_amg])
2131 && ((cv = cvp[off=neg_amg]) || (cv = cvp[off=subtr_amg]))) {
2132 SV* const nullsv=sv_2mortal(newSViv(0));
2134 SV* const lessp = amagic_call(left,nullsv,
2135 lt_amg,AMGf_noright);
2136 logic = SvTRUE(lessp);
2138 SV* const lessp = amagic_call(left,nullsv,
2139 ncmp_amg,AMGf_noright);
2140 logic = (SvNV(lessp) < 0);
2143 if (off==subtr_amg) {
2154 if ((cv = cvp[off=subtr_amg])) {
2156 left = sv_2mortal(newSViv(0));
2161 case iter_amg: /* XXXX Eventually should do to_gv. */
2162 case ftest_amg: /* XXXX Eventually should do to_gv. */
2165 return NULL; /* Delegate operation to standard mechanisms. */
2173 return left; /* Delegate operation to standard mechanisms. */
2178 if (!cv) goto not_found;
2179 } else if (!(AMGf_noright & flags) && SvAMAGIC(right)
2180 && (stash = SvSTASH(SvRV(right)))
2181 && (mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table))
2182 && (cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
2183 ? (amtp = (AMT*)mg->mg_ptr)->table
2185 && (cv = cvp[off=method])) { /* Method for right
2188 } else if (((ocvp && oamtp->fallback > AMGfallNEVER
2189 && (cvp=ocvp) && (lr = -1))
2190 || (cvp && amtp->fallback > AMGfallNEVER && (lr=1)))
2191 && !(flags & AMGf_unary)) {
2192 /* We look for substitution for
2193 * comparison operations and
2195 if (method==concat_amg || method==concat_ass_amg
2196 || method==repeat_amg || method==repeat_ass_amg) {
2197 return NULL; /* Delegate operation to string conversion */
2218 if ((off != -1) && (cv = cvp[off]))
2223 not_found: /* No method found, either report or croak */
2231 return left; /* Delegate operation to standard mechanisms. */
2234 if (ocvp && (cv=ocvp[nomethod_amg])) { /* Call report method */
2235 notfound = 1; lr = -1;
2236 } else if (cvp && (cv=cvp[nomethod_amg])) {
2237 notfound = 1; lr = 1;
2238 } else if ((amtp && amtp->fallback >= AMGfallYES) && !DEBUG_o_TEST) {
2239 /* Skip generating the "no method found" message. */
2243 if (off==-1) off=method;
2244 msg = sv_2mortal(Perl_newSVpvf(aTHX_
2245 "Operation \"%s\": no method found,%sargument %s%s%s%s",
2246 AMG_id2name(method + assignshift),
2247 (flags & AMGf_unary ? " " : "\n\tleft "),
2249 "in overloaded package ":
2250 "has no overloaded magic",
2252 HvNAME_get(SvSTASH(SvRV(left))):
2255 ",\n\tright argument in overloaded package ":
2258 : ",\n\tright argument has no overloaded magic"),
2260 HvNAME_get(SvSTASH(SvRV(right))):
2262 if (amtp && amtp->fallback >= AMGfallYES) {
2263 DEBUG_o( Perl_deb(aTHX_ "%s", SvPVX_const(msg)) );
2265 Perl_croak(aTHX_ "%"SVf, SVfARG(msg));
2269 force_cpy = force_cpy || assign;
2274 DEBUG_o(Perl_deb(aTHX_
2275 "Overloaded operator \"%s\"%s%s%s:\n\tmethod%s found%s in package %s%s\n",
2277 method+assignshift==off? "" :
2279 method+assignshift==off? "" :
2280 AMG_id2name(method+assignshift),
2281 method+assignshift==off? "" : "\")",
2282 flags & AMGf_unary? "" :
2283 lr==1 ? " for right argument": " for left argument",
2284 flags & AMGf_unary? " for argument" : "",
2285 stash ? HvNAME_get(stash) : "null",
2286 fl? ",\n\tassignment variant used": "") );
2289 /* Since we use shallow copy during assignment, we need
2290 * to dublicate the contents, probably calling user-supplied
2291 * version of copy operator
2293 /* We need to copy in following cases:
2294 * a) Assignment form was called.
2295 * assignshift==1, assign==T, method + 1 == off
2296 * b) Increment or decrement, called directly.
2297 * assignshift==0, assign==0, method + 0 == off
2298 * c) Increment or decrement, translated to assignment add/subtr.
2299 * assignshift==0, assign==T,
2301 * d) Increment or decrement, translated to nomethod.
2302 * assignshift==0, assign==0,
2304 * e) Assignment form translated to nomethod.
2305 * assignshift==1, assign==T, method + 1 != off
2308 /* off is method, method+assignshift, or a result of opcode substitution.
2309 * In the latter case assignshift==0, so only notfound case is important.
2311 if (( (method + assignshift == off)
2312 && (assign || (method == inc_amg) || (method == dec_amg)))
2322 const bool oldcatch = CATCH_GET;
2325 Zero(&myop, 1, BINOP);
2326 myop.op_last = (OP *) &myop;
2327 myop.op_next = NULL;
2328 myop.op_flags = OPf_WANT_SCALAR | OPf_STACKED;
2330 PUSHSTACKi(PERLSI_OVERLOAD);
2333 PL_op = (OP *) &myop;
2334 if (PERLDB_SUB && PL_curstash != PL_debstash)
2335 PL_op->op_private |= OPpENTERSUB_DB;
2339 EXTEND(SP, notfound + 5);
2340 PUSHs(lr>0? right: left);
2341 PUSHs(lr>0? left: right);
2342 PUSHs( lr > 0 ? &PL_sv_yes : ( assign ? &PL_sv_undef : &PL_sv_no ));
2344 PUSHs(newSVpvn_flags(AMG_id2name(method + assignshift),
2345 AMG_id2namelen(method + assignshift), SVs_TEMP));
2347 PUSHs(MUTABLE_SV(cv));
2350 if ((PL_op = PL_ppaddr[OP_ENTERSUB](aTHX)))
2358 CATCH_SET(oldcatch);
2365 ans=SvIV(res)<=0; break;
2368 ans=SvIV(res)<0; break;
2371 ans=SvIV(res)>=0; break;
2374 ans=SvIV(res)>0; break;
2377 ans=SvIV(res)==0; break;
2380 ans=SvIV(res)!=0; break;
2383 SvSetSV(left,res); return left;
2385 ans=!SvTRUE(res); break;
2390 } else if (method==copy_amg) {
2392 Perl_croak(aTHX_ "Copy method did not return a reference");
2394 return SvREFCNT_inc(SvRV(res));
2402 =for apidoc is_gv_magical_sv
2404 Returns C<TRUE> if given the name of a magical GV.
2406 Currently only useful internally when determining if a GV should be
2407 created even in rvalue contexts.
2409 C<flags> is not used at present but available for future extension to
2410 allow selecting particular classes of magical variable.
2412 Currently assumes that C<name> is NUL terminated (as well as len being valid).
2413 This assumption is met by all callers within the perl core, which all pass
2414 pointers returned by SvPV.
2420 Perl_is_gv_magical_sv(pTHX_ SV *const name_sv, U32 flags)
2423 const char *const name = SvPV_const(name_sv, len);
2425 PERL_UNUSED_ARG(flags);
2426 PERL_ARGS_ASSERT_IS_GV_MAGICAL_SV;
2429 const char * const name1 = name + 1;
2432 if (len == 3 && name[1] == 'S' && name[2] == 'A')
2436 if (len == 8 && strEQ(name1, "VERLOAD"))
2440 if (len == 3 && name[1] == 'I' && name[2] == 'G')
2443 /* Using ${^...} variables is likely to be sufficiently rare that
2444 it seems sensible to avoid the space hit of also checking the
2446 case '\017': /* ${^OPEN} */
2447 if (strEQ(name1, "PEN"))
2450 case '\024': /* ${^TAINT} */
2451 if (strEQ(name1, "AINT"))
2454 case '\025': /* ${^UNICODE} */
2455 if (strEQ(name1, "NICODE"))
2457 if (strEQ(name1, "TF8LOCALE"))
2460 case '\027': /* ${^WARNING_BITS} */
2461 if (strEQ(name1, "ARNING_BITS"))
2474 const char *end = name + len;
2475 while (--end > name) {
2483 /* Because we're already assuming that name is NUL terminated
2484 below, we can treat an empty name as "\0" */
2510 case '\001': /* $^A */
2511 case '\003': /* $^C */
2512 case '\004': /* $^D */
2513 case '\005': /* $^E */
2514 case '\006': /* $^F */
2515 case '\010': /* $^H */
2516 case '\011': /* $^I, NOT \t in EBCDIC */
2517 case '\014': /* $^L */
2518 case '\016': /* $^N */
2519 case '\017': /* $^O */
2520 case '\020': /* $^P */
2521 case '\023': /* $^S */
2522 case '\024': /* $^T */
2523 case '\026': /* $^V */
2524 case '\027': /* $^W */
2544 Perl_gv_name_set(pTHX_ GV *gv, const char *name, U32 len, U32 flags)
2549 PERL_ARGS_ASSERT_GV_NAME_SET;
2550 PERL_UNUSED_ARG(flags);
2553 Perl_croak(aTHX_ "panic: gv name too long (%"UVuf")", (UV) len);
2555 if (!(flags & GV_ADD) && GvNAME_HEK(gv)) {
2556 unshare_hek(GvNAME_HEK(gv));
2559 PERL_HASH(hash, name, len);
2560 GvNAME_HEK(gv) = share_hek(name, len, hash);
2564 =for apidoc gv_try_downgrade
2566 If the typeglob C<gv> can be expressed more succinctly, by having
2567 something other than a real GV in its place in the stash, replace it
2568 with the optimised form. Basic requirements for this are that C<gv>
2569 is a real typeglob, is sufficiently ordinary, and is only referenced
2570 from its package. This function is meant to be used when a GV has been
2571 looked up in part to see what was there, causing upgrading, but based
2572 on what was found it turns out that the real GV isn't required after all.
2574 If C<gv> is a completely empty typeglob, it is deleted from the stash.
2576 If C<gv> is a typeglob containing only a sufficiently-ordinary constant
2577 sub, the typeglob is replaced with a scalar-reference placeholder that
2578 more compactly represents the same thing.
2584 Perl_gv_try_downgrade(pTHX_ GV *gv)
2590 PERL_ARGS_ASSERT_GV_TRY_DOWNGRADE;
2592 /* XXX Why and where does this leave dangling pointers during global
2594 if (PL_dirty) return;
2596 if (!(SvREFCNT(gv) == 1 && SvTYPE(gv) == SVt_PVGV && !SvFAKE(gv) &&
2597 !SvOBJECT(gv) && !SvREADONLY(gv) &&
2598 isGV_with_GP(gv) && GvGP(gv) &&
2599 !GvINTRO(gv) && GvREFCNT(gv) == 1 &&
2600 !GvSV(gv) && !GvAV(gv) && !GvHV(gv) && !GvIOp(gv) && !GvFORM(gv) &&
2601 GvEGVx(gv) == gv && (stash = GvSTASH(gv))))
2603 if (SvMAGICAL(gv)) {
2605 /* only backref magic is allowed */
2606 if (SvGMAGICAL(gv) || SvSMAGICAL(gv))
2608 for (mg = SvMAGIC(gv); mg; mg = mg->mg_moremagic) {
2609 if (mg->mg_type != PERL_MAGIC_backref)
2615 HEK *gvnhek = GvNAME_HEK(gv);
2616 (void)hv_delete(stash, HEK_KEY(gvnhek),
2617 HEK_UTF8(gvnhek) ? -HEK_LEN(gvnhek) : HEK_LEN(gvnhek), G_DISCARD);
2618 } else if (GvMULTI(gv) && cv &&
2619 !SvOBJECT(cv) && !SvMAGICAL(cv) && !SvREADONLY(cv) &&
2620 CvSTASH(cv) == stash && CvGV(cv) == gv &&
2621 CvCONST(cv) && !CvMETHOD(cv) && !CvLVALUE(cv) && !CvUNIQUE(cv) &&
2622 !CvNODEBUG(cv) && !CvCLONE(cv) && !CvCLONED(cv) && !CvANON(cv) &&
2623 (namehek = GvNAME_HEK(gv)) &&
2624 (gvp = hv_fetch(stash, HEK_KEY(namehek),
2625 HEK_LEN(namehek)*(HEK_UTF8(namehek) ? -1 : 1), 0)) &&
2627 SV *value = SvREFCNT_inc(CvXSUBANY(cv).any_ptr);
2631 SvFLAGS(gv) = SVt_IV|SVf_ROK;
2632 SvANY(gv) = (XPVGV*)((char*)&(gv->sv_u.svu_iv) -
2633 STRUCT_OFFSET(XPVIV, xiv_iv));
2634 SvRV_set(gv, value);
2640 * c-indentation-style: bsd
2642 * indent-tabs-mode: t
2645 * ex: set ts=8 sts=4 sw=4 noet: