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);
1222 else if (len == 3 && sv_type == SVt_PVAV
1223 && strnEQ(name, "ISA", 3)
1224 && (!GvAV(gv) || !SvSMAGICAL(GvAV(gv))))
1225 gv_magicalize_isa(gv);
1228 } else if (no_init) {
1230 } else if (no_expand && SvROK(gv)) {
1234 /* Adding a new symbol.
1235 Unless of course there was already something non-GV here, in which case
1236 we want to behave as if there was always a GV here, containing some sort
1238 Otherwise we run the risk of creating things like GvIO, which can cause
1239 subtle bugs. eg the one that tripped up SQL::Translator */
1241 faking_it = SvOK(gv);
1243 if (add & GV_ADDWARN)
1244 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL), "Had to create %s unexpectedly", nambeg);
1245 gv_init(gv, stash, name, len, add & GV_ADDMULTI);
1246 gv_init_sv(gv, faking_it ? SVt_PVCV : sv_type);
1248 if (isALPHA(name[0]) && ! (isLEXWARN_on ? ckWARN(WARN_ONCE)
1249 : (PL_dowarn & G_WARN_ON ) ) )
1252 /* set up magic where warranted */
1253 if (stash != PL_defstash) { /* not the main stash */
1254 /* We only have to check for four names here: EXPORT, ISA, OVERLOAD
1255 and VERSION. All the others apply only to the main stash. */
1257 const char * const name2 = name + 1;
1260 if (strnEQ(name2, "XPORT", 5))
1264 if (strEQ(name2, "SA"))
1265 gv_magicalize_isa(gv);
1268 if (strEQ(name2, "VERLOAD"))
1269 gv_magicalize_overload(gv);
1272 if (strEQ(name2, "ERSION"))
1282 /* Nothing else to do.
1283 The compiler will probably turn the switch statement into a
1284 branch table. Make sure we avoid even that small overhead for
1285 the common case of lower case variable names. */
1289 const char * const name2 = name + 1;
1292 if (strEQ(name2, "RGV")) {
1293 IoFLAGS(GvIOn(gv)) |= IOf_ARGV|IOf_START;
1295 else if (strEQ(name2, "RGVOUT")) {
1300 if (strnEQ(name2, "XPORT", 5))
1304 if (strEQ(name2, "SA")) {
1305 gv_magicalize_isa(gv);
1309 if (strEQ(name2, "VERLOAD")) {
1310 gv_magicalize_overload(gv);
1314 if (strEQ(name2, "IG")) {
1317 if (!PL_psig_name) {
1318 Newxz(PL_psig_name, 2 * SIG_SIZE, SV*);
1319 Newxz(PL_psig_pend, SIG_SIZE, int);
1320 PL_psig_ptr = PL_psig_name + SIG_SIZE;
1322 /* I think that the only way to get here is to re-use an
1323 embedded perl interpreter, where the previous
1324 use didn't clean up fully because
1325 PL_perl_destruct_level was 0. I'm not sure that we
1326 "support" that, in that I suspect in that scenario
1327 there are sufficient other garbage values left in the
1328 interpreter structure that something else will crash
1329 before we get here. I suspect that this is one of
1330 those "doctor, it hurts when I do this" bugs. */
1331 Zero(PL_psig_name, 2 * SIG_SIZE, SV*);
1332 Zero(PL_psig_pend, SIG_SIZE, int);
1336 hv_magic(hv, NULL, PERL_MAGIC_sig);
1337 for (i = 1; i < SIG_SIZE; i++) {
1338 SV * const * const init = hv_fetch(hv, PL_sig_name[i], strlen(PL_sig_name[i]), 1);
1340 sv_setsv(*init, &PL_sv_undef);
1345 if (strEQ(name2, "ERSION"))
1348 case '\003': /* $^CHILD_ERROR_NATIVE */
1349 if (strEQ(name2, "HILD_ERROR_NATIVE"))
1352 case '\005': /* $^ENCODING */
1353 if (strEQ(name2, "NCODING"))
1356 case '\007': /* $^GLOBAL_PHASE */
1357 if (strEQ(name2, "LOBAL_PHASE"))
1360 case '\015': /* $^MATCH */
1361 if (strEQ(name2, "ATCH"))
1363 case '\017': /* $^OPEN */
1364 if (strEQ(name2, "PEN"))
1367 case '\020': /* $^PREMATCH $^POSTMATCH */
1368 if (strEQ(name2, "REMATCH") || strEQ(name2, "OSTMATCH"))
1371 case '\024': /* ${^TAINT} */
1372 if (strEQ(name2, "AINT"))
1375 case '\025': /* ${^UNICODE}, ${^UTF8LOCALE} */
1376 if (strEQ(name2, "NICODE"))
1378 if (strEQ(name2, "TF8LOCALE"))
1380 if (strEQ(name2, "TF8CACHE"))
1383 case '\027': /* $^WARNING_BITS */
1384 if (strEQ(name2, "ARNING_BITS"))
1397 /* Ensures that we have an all-digit variable, ${"1foo"} fails
1399 /* This snippet is taken from is_gv_magical */
1400 const char *end = name + len;
1401 while (--end > name) {
1402 if (!isDIGIT(*end)) return gv;
1409 /* Names of length 1. (Or 0. But name is NUL terminated, so that will
1410 be case '\0' in this switch statement (ie a default case) */
1416 sv_type == SVt_PVAV ||
1417 sv_type == SVt_PVHV ||
1418 sv_type == SVt_PVCV ||
1419 sv_type == SVt_PVFM ||
1422 PL_sawampersand = TRUE;
1426 sv_setpv(GvSVn(gv),PL_chopset);
1430 #ifdef COMPLEX_STATUS
1431 SvUPGRADE(GvSVn(gv), SVt_PVLV);
1437 /* If %! has been used, automatically load Errno.pm. */
1439 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1441 /* magicalization must be done before require_tie_mod is called */
1442 if (sv_type == SVt_PVHV || sv_type == SVt_PVGV)
1443 require_tie_mod(gv, "!", newSVpvs("Errno"), "TIEHASH", 1);
1448 GvMULTI_on(gv); /* no used once warnings here */
1450 AV* const av = GvAVn(gv);
1451 SV* const avc = (*name == '+') ? MUTABLE_SV(av) : NULL;
1453 sv_magic(MUTABLE_SV(av), avc, PERL_MAGIC_regdata, NULL, 0);
1454 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1456 SvREADONLY_on(GvSVn(gv));
1459 if (sv_type == SVt_PVHV || sv_type == SVt_PVGV)
1460 require_tie_mod(gv, name, newSVpvs("Tie::Hash::NamedCapture"), "TIEHASH", 0);
1466 if (sv_type == SVt_PV)
1467 Perl_ck_warner_d(aTHX_ packWARN2(WARN_DEPRECATED, WARN_SYNTAX),
1468 "$%c is no longer supported", *name);
1471 sv_setiv(GvSVn(gv), (IV)(IoFLAGS(GvIOp(PL_defoutgv)) & IOf_FLUSH) != 0);
1474 case '\010': /* $^H */
1476 HV *const hv = GvHVn(gv);
1477 hv_magic(hv, NULL, PERL_MAGIC_hints);
1480 case '\023': /* $^S */
1482 SvREADONLY_on(GvSVn(gv));
1506 case '\001': /* $^A */
1507 case '\003': /* $^C */
1508 case '\004': /* $^D */
1509 case '\005': /* $^E */
1510 case '\006': /* $^F */
1511 case '\011': /* $^I, NOT \t in EBCDIC */
1512 case '\016': /* $^N */
1513 case '\017': /* $^O */
1514 case '\020': /* $^P */
1515 case '\024': /* $^T */
1516 case '\027': /* $^W */
1518 sv_magic(GvSVn(gv), MUTABLE_SV(gv), PERL_MAGIC_sv, name, len);
1521 case '\014': /* $^L */
1522 sv_setpvs(GvSVn(gv),"\f");
1523 PL_formfeed = GvSVn(gv);
1526 sv_setpvs(GvSVn(gv),"\034");
1530 SV * const sv = GvSVn(gv);
1531 if (!sv_derived_from(PL_patchlevel, "version"))
1532 upg_version(PL_patchlevel, TRUE);
1533 GvSV(gv) = vnumify(PL_patchlevel);
1534 SvREADONLY_on(GvSV(gv));
1538 case '\026': /* $^V */
1540 SV * const sv = GvSVn(gv);
1541 GvSV(gv) = new_version(PL_patchlevel);
1542 SvREADONLY_on(GvSV(gv));
1552 Perl_gv_fullname4(pTHX_ SV *sv, const GV *gv, const char *prefix, bool keepmain)
1556 const HV * const hv = GvSTASH(gv);
1558 PERL_ARGS_ASSERT_GV_FULLNAME4;
1564 sv_setpv(sv, prefix ? prefix : "");
1566 name = HvNAME_get(hv);
1568 namelen = HvNAMELEN_get(hv);
1574 if (keepmain || strNE(name, "main")) {
1575 sv_catpvn(sv,name,namelen);
1578 sv_catpvn(sv,GvNAME(gv),GvNAMELEN(gv));
1582 Perl_gv_efullname4(pTHX_ SV *sv, const GV *gv, const char *prefix, bool keepmain)
1584 const GV * const egv = GvEGVx(gv);
1586 PERL_ARGS_ASSERT_GV_EFULLNAME4;
1588 gv_fullname4(sv, egv ? egv : gv, prefix, keepmain);
1592 Perl_gv_check(pTHX_ const HV *stash)
1597 PERL_ARGS_ASSERT_GV_CHECK;
1599 if (!HvARRAY(stash))
1601 for (i = 0; i <= (I32) HvMAX(stash); i++) {
1603 for (entry = HvARRAY(stash)[i]; entry; entry = HeNEXT(entry)) {
1606 if (HeKEY(entry)[HeKLEN(entry)-1] == ':' &&
1607 (gv = MUTABLE_GV(HeVAL(entry))) && isGV(gv) && (hv = GvHV(gv)))
1609 if (hv != PL_defstash && hv != stash)
1610 gv_check(hv); /* nested package */
1612 else if (isALPHA(*HeKEY(entry))) {
1614 gv = MUTABLE_GV(HeVAL(entry));
1615 if (SvTYPE(gv) != SVt_PVGV || GvMULTI(gv))
1618 CopLINE_set(PL_curcop, GvLINE(gv));
1620 CopFILE(PL_curcop) = (char *)file; /* set for warning */
1622 CopFILEGV(PL_curcop)
1623 = gv_fetchfile_flags(file, HEK_LEN(GvFILE_HEK(gv)), 0);
1625 Perl_warner(aTHX_ packWARN(WARN_ONCE),
1626 "Name \"%s::%s\" used only once: possible typo",
1627 HvNAME_get(stash), GvNAME(gv));
1634 Perl_newGVgen(pTHX_ const char *pack)
1638 PERL_ARGS_ASSERT_NEWGVGEN;
1640 return gv_fetchpv(Perl_form(aTHX_ "%s::_GEN_%ld", pack, (long)PL_gensym++),
1644 /* hopefully this is only called on local symbol table entries */
1647 Perl_gp_ref(pTHX_ GP *gp)
1655 /* If the GP they asked for a reference to contains
1656 a method cache entry, clear it first, so that we
1657 don't infect them with our cached entry */
1658 SvREFCNT_dec(gp->gp_cv);
1667 Perl_gp_free(pTHX_ GV *gv)
1672 if (!gv || !isGV_with_GP(gv) || !(gp = GvGP(gv)))
1674 if (gp->gp_refcnt == 0) {
1675 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
1676 "Attempt to free unreferenced glob pointers"
1677 pTHX__FORMAT pTHX__VALUE);
1680 if (--gp->gp_refcnt > 0) {
1681 if (gp->gp_egv == gv)
1687 if (gp->gp_file_hek)
1688 unshare_hek(gp->gp_file_hek);
1689 SvREFCNT_dec(gp->gp_sv);
1690 SvREFCNT_dec(gp->gp_av);
1691 /* FIXME - another reference loop GV -> symtab -> GV ?
1692 Somehow gp->gp_hv can end up pointing at freed garbage. */
1693 if (gp->gp_hv && SvTYPE(gp->gp_hv) == SVt_PVHV) {
1694 const char *hvname = HvNAME_get(gp->gp_hv);
1695 if (PL_stashcache && hvname)
1696 (void)hv_delete(PL_stashcache, hvname, HvNAMELEN_get(gp->gp_hv),
1698 SvREFCNT_dec(gp->gp_hv);
1700 SvREFCNT_dec(gp->gp_io);
1701 SvREFCNT_dec(gp->gp_cv);
1702 SvREFCNT_dec(gp->gp_form);
1709 Perl_magic_freeovrld(pTHX_ SV *sv, MAGIC *mg)
1711 AMT * const amtp = (AMT*)mg->mg_ptr;
1712 PERL_UNUSED_ARG(sv);
1714 PERL_ARGS_ASSERT_MAGIC_FREEOVRLD;
1716 if (amtp && AMT_AMAGIC(amtp)) {
1718 for (i = 1; i < NofAMmeth; i++) {
1719 CV * const cv = amtp->table[i];
1721 SvREFCNT_dec(MUTABLE_SV(cv));
1722 amtp->table[i] = NULL;
1729 /* Updates and caches the CV's */
1731 * 1 on success and there is some overload
1732 * 0 if there is no overload
1733 * -1 if some error occurred and it couldn't croak
1737 Perl_Gv_AMupdate(pTHX_ HV *stash, bool destructing)
1740 MAGIC* const mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1742 const struct mro_meta* stash_meta = HvMROMETA(stash);
1745 PERL_ARGS_ASSERT_GV_AMUPDATE;
1747 newgen = PL_sub_generation + stash_meta->pkg_gen + stash_meta->cache_gen;
1749 const AMT * const amtp = (AMT*)mg->mg_ptr;
1750 if (amtp->was_ok_am == PL_amagic_generation
1751 && amtp->was_ok_sub == newgen) {
1752 return AMT_OVERLOADED(amtp) ? 1 : 0;
1754 sv_unmagic(MUTABLE_SV(stash), PERL_MAGIC_overload_table);
1757 DEBUG_o( Perl_deb(aTHX_ "Recalcing overload magic in package %s\n",HvNAME_get(stash)) );
1760 amt.was_ok_am = PL_amagic_generation;
1761 amt.was_ok_sub = newgen;
1762 amt.fallback = AMGfallNO;
1766 int filled = 0, have_ovl = 0;
1769 /* Work with "fallback" key, which we assume to be first in PL_AMG_names */
1771 /* Try to find via inheritance. */
1772 GV *gv = gv_fetchmeth(stash, PL_AMG_names[0], 2, -1);
1773 SV * const sv = gv ? GvSV(gv) : NULL;
1777 lim = DESTROY_amg; /* Skip overloading entries. */
1778 #ifdef PERL_DONT_CREATE_GVSV
1780 NOOP; /* Equivalent to !SvTRUE and !SvOK */
1783 else if (SvTRUE(sv))
1784 amt.fallback=AMGfallYES;
1786 amt.fallback=AMGfallNEVER;
1788 for (i = 1; i < lim; i++)
1789 amt.table[i] = NULL;
1790 for (; i < NofAMmeth; i++) {
1791 const char * const cooky = PL_AMG_names[i];
1792 /* Human-readable form, for debugging: */
1793 const char * const cp = (i >= DESTROY_amg ? cooky : AMG_id2name(i));
1794 const STRLEN l = PL_AMG_namelens[i];
1796 DEBUG_o( Perl_deb(aTHX_ "Checking overloading of \"%s\" in package \"%.256s\"\n",
1797 cp, HvNAME_get(stash)) );
1798 /* don't fill the cache while looking up!
1799 Creation of inheritance stubs in intermediate packages may
1800 conflict with the logic of runtime method substitution.
1801 Indeed, for inheritance A -> B -> C, if C overloads "+0",
1802 then we could have created stubs for "(+0" in A and C too.
1803 But if B overloads "bool", we may want to use it for
1804 numifying instead of C's "+0". */
1805 if (i >= DESTROY_amg)
1806 gv = Perl_gv_fetchmeth_autoload(aTHX_ stash, cooky, l, 0);
1807 else /* Autoload taken care of below */
1808 gv = Perl_gv_fetchmeth(aTHX_ stash, cooky, l, -1);
1810 if (gv && (cv = GvCV(gv))) {
1812 if (GvNAMELEN(CvGV(cv)) == 3 && strEQ(GvNAME(CvGV(cv)), "nil")
1813 && strEQ(hvname = HvNAME_get(GvSTASH(CvGV(cv))), "overload")) {
1814 /* This is a hack to support autoloading..., while
1815 knowing *which* methods were declared as overloaded. */
1816 /* GvSV contains the name of the method. */
1818 SV *gvsv = GvSV(gv);
1820 DEBUG_o( Perl_deb(aTHX_ "Resolving method \"%"SVf256\
1821 "\" for overloaded \"%s\" in package \"%.256s\"\n",
1822 (void*)GvSV(gv), cp, hvname) );
1823 if (!gvsv || !SvPOK(gvsv)
1824 || !(ngv = gv_fetchmethod_autoload(stash, SvPVX_const(gvsv),
1827 /* Can be an import stub (created by "can"). */
1832 const char * const name = (gvsv && SvPOK(gvsv)) ? SvPVX_const(gvsv) : "???";
1833 Perl_croak(aTHX_ "%s method \"%.256s\" overloading \"%s\" "\
1834 "in package \"%.256s\"",
1835 (GvCVGEN(gv) ? "Stub found while resolving"
1840 cv = GvCV(gv = ngv);
1842 DEBUG_o( Perl_deb(aTHX_ "Overloading \"%s\" in package \"%.256s\" via \"%.256s::%.256s\"\n",
1843 cp, HvNAME_get(stash), HvNAME_get(GvSTASH(CvGV(cv))),
1844 GvNAME(CvGV(cv))) );
1846 if (i < DESTROY_amg)
1848 } else if (gv) { /* Autoloaded... */
1849 cv = MUTABLE_CV(gv);
1852 amt.table[i]=MUTABLE_CV(SvREFCNT_inc_simple(cv));
1855 AMT_AMAGIC_on(&amt);
1857 AMT_OVERLOADED_on(&amt);
1858 sv_magic(MUTABLE_SV(stash), 0, PERL_MAGIC_overload_table,
1859 (char*)&amt, sizeof(AMT));
1863 /* Here we have no table: */
1865 AMT_AMAGIC_off(&amt);
1866 sv_magic(MUTABLE_SV(stash), 0, PERL_MAGIC_overload_table,
1867 (char*)&amt, sizeof(AMTS));
1873 Perl_gv_handler(pTHX_ HV *stash, I32 id)
1879 struct mro_meta* stash_meta;
1881 if (!stash || !HvNAME_get(stash))
1884 stash_meta = HvMROMETA(stash);
1885 newgen = PL_sub_generation + stash_meta->pkg_gen + stash_meta->cache_gen;
1887 mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1890 /* If we're looking up a destructor to invoke, we must avoid
1891 * that Gv_AMupdate croaks, because we might be dying already */
1892 if (Gv_AMupdate(stash, id == DESTROY_amg) == -1) {
1893 /* and if it didn't found a destructor, we fall back
1894 * to a simpler method that will only look for the
1895 * destructor instead of the whole magic */
1896 if (id == DESTROY_amg) {
1897 GV * const gv = gv_fetchmethod(stash, "DESTROY");
1903 mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table);
1906 amtp = (AMT*)mg->mg_ptr;
1907 if ( amtp->was_ok_am != PL_amagic_generation
1908 || amtp->was_ok_sub != newgen )
1910 if (AMT_AMAGIC(amtp)) {
1911 CV * const ret = amtp->table[id];
1912 if (ret && isGV(ret)) { /* Autoloading stab */
1913 /* Passing it through may have resulted in a warning
1914 "Inherited AUTOLOAD for a non-method deprecated", since
1915 our caller is going through a function call, not a method call.
1916 So return the CV for AUTOLOAD, setting $AUTOLOAD. */
1917 GV * const gv = gv_fetchmethod(stash, PL_AMG_names[id]);
1929 /* Implement tryAMAGICun_MG macro.
1930 Do get magic, then see if the stack arg is overloaded and if so call it.
1932 AMGf_set return the arg using SETs rather than assigning to
1934 AMGf_numeric apply sv_2num to the stack arg.
1938 Perl_try_amagic_un(pTHX_ int method, int flags) {
1942 SV* const arg = TOPs;
1946 if (SvAMAGIC(arg) && (tmpsv = amagic_call(arg, &PL_sv_undef, method,
1947 AMGf_noright | AMGf_unary))) {
1948 if (flags & AMGf_set) {
1953 if (SvPADMY(TARG)) {
1954 sv_setsv(TARG, tmpsv);
1964 if ((flags & AMGf_numeric) && SvROK(arg))
1970 /* Implement tryAMAGICbin_MG macro.
1971 Do get magic, then see if the two stack args are overloaded and if so
1974 AMGf_set return the arg using SETs rather than assigning to
1976 AMGf_assign op may be called as mutator (eg +=)
1977 AMGf_numeric apply sv_2num to the stack arg.
1981 Perl_try_amagic_bin(pTHX_ int method, int flags) {
1984 SV* const left = TOPm1s;
1985 SV* const right = TOPs;
1991 if (SvAMAGIC(left) || SvAMAGIC(right)) {
1992 SV * const tmpsv = amagic_call(left, right, method,
1993 ((flags & AMGf_assign) && opASSIGN ? AMGf_assign: 0));
1995 if (flags & AMGf_set) {
2002 if (opASSIGN || SvPADMY(TARG)) {
2003 sv_setsv(TARG, tmpsv);
2013 if (flags & AMGf_numeric) {
2015 *(sp-1) = sv_2num(left);
2017 *sp = sv_2num(right);
2023 Perl_amagic_deref_call(pTHX_ SV *ref, int method) {
2026 PERL_ARGS_ASSERT_AMAGIC_DEREF_CALL;
2028 while (SvAMAGIC(ref) &&
2029 (tmpsv = amagic_call(ref, &PL_sv_undef, method,
2030 AMGf_noright | AMGf_unary))) {
2032 Perl_croak(aTHX_ "Overloaded dereference did not return a reference");
2033 if (tmpsv == ref || SvRV(tmpsv) == SvRV(ref)) {
2034 /* Bail out if it returns us the same reference. */
2039 return tmpsv ? tmpsv : ref;
2043 Perl_amagic_call(pTHX_ SV *left, SV *right, int method, int flags)
2048 CV **cvp=NULL, **ocvp=NULL;
2049 AMT *amtp=NULL, *oamtp=NULL;
2050 int off = 0, off1, lr = 0, notfound = 0;
2051 int postpr = 0, force_cpy = 0;
2052 int assign = AMGf_assign & flags;
2053 const int assignshift = assign ? 1 : 0;
2059 PERL_ARGS_ASSERT_AMAGIC_CALL;
2061 if ( PL_curcop->cop_hints & HINT_NO_AMAGIC ) {
2062 SV *lex_mask = cop_hints_fetch_pvs(PL_curcop, "overloading", 0);
2064 if ( !lex_mask || !SvOK(lex_mask) )
2065 /* overloading lexically disabled */
2067 else if ( lex_mask && SvPOK(lex_mask) ) {
2068 /* we have an entry in the hints hash, check if method has been
2069 * masked by overloading.pm */
2071 const int offset = method / 8;
2072 const int bit = method % 8;
2073 char *pv = SvPV(lex_mask, len);
2075 /* Bit set, so this overloading operator is disabled */
2076 if ( (STRLEN)offset < len && pv[offset] & ( 1 << bit ) )
2081 if (!(AMGf_noleft & flags) && SvAMAGIC(left)
2082 && (stash = SvSTASH(SvRV(left)))
2083 && (mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table))
2084 && (ocvp = cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
2085 ? (oamtp = amtp = (AMT*)mg->mg_ptr)->table
2087 && ((cv = cvp[off=method+assignshift])
2088 || (assign && amtp->fallback > AMGfallNEVER && /* fallback to
2094 cv = cvp[off=method])))) {
2095 lr = -1; /* Call method for left argument */
2097 if (cvp && amtp->fallback > AMGfallNEVER && flags & AMGf_unary) {
2100 /* look for substituted methods */
2101 /* In all the covered cases we should be called with assign==0. */
2105 if ((cv = cvp[off=add_ass_amg])
2106 || ((cv = cvp[off = add_amg]) && (force_cpy = 0, postpr = 1))) {
2107 right = &PL_sv_yes; lr = -1; assign = 1;
2112 if ((cv = cvp[off = subtr_ass_amg])
2113 || ((cv = cvp[off = subtr_amg]) && (force_cpy = 0, postpr=1))) {
2114 right = &PL_sv_yes; lr = -1; assign = 1;
2118 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=string_amg]));
2121 (void)((cv = cvp[off=string_amg]) || (cv = cvp[off=bool__amg]));
2124 (void)((cv = cvp[off=numer_amg]) || (cv = cvp[off=bool__amg]));
2127 (void)((cv = cvp[off=bool__amg])
2128 || (cv = cvp[off=numer_amg])
2129 || (cv = cvp[off=string_amg]));
2136 * SV* ref causes confusion with the interpreter variable of
2139 SV* const tmpRef=SvRV(left);
2140 if (!SvROK(tmpRef) && SvTYPE(tmpRef) <= SVt_PVMG) {
2142 * Just to be extra cautious. Maybe in some
2143 * additional cases sv_setsv is safe, too.
2145 SV* const newref = newSVsv(tmpRef);
2146 SvOBJECT_on(newref);
2147 /* As a bit of a source compatibility hack, SvAMAGIC() and
2148 friends dereference an RV, to behave the same was as when
2149 overloading was stored on the reference, not the referant.
2150 Hence we can't use SvAMAGIC_on()
2152 SvFLAGS(newref) |= SVf_AMAGIC;
2153 SvSTASH_set(newref, MUTABLE_HV(SvREFCNT_inc(SvSTASH(tmpRef))));
2159 if ((cvp[off1=lt_amg] || cvp[off1=ncmp_amg])
2160 && ((cv = cvp[off=neg_amg]) || (cv = cvp[off=subtr_amg]))) {
2161 SV* const nullsv=sv_2mortal(newSViv(0));
2163 SV* const lessp = amagic_call(left,nullsv,
2164 lt_amg,AMGf_noright);
2165 logic = SvTRUE(lessp);
2167 SV* const lessp = amagic_call(left,nullsv,
2168 ncmp_amg,AMGf_noright);
2169 logic = (SvNV(lessp) < 0);
2172 if (off==subtr_amg) {
2183 if ((cv = cvp[off=subtr_amg])) {
2185 left = sv_2mortal(newSViv(0));
2190 case iter_amg: /* XXXX Eventually should do to_gv. */
2191 case ftest_amg: /* XXXX Eventually should do to_gv. */
2194 return NULL; /* Delegate operation to standard mechanisms. */
2202 return left; /* Delegate operation to standard mechanisms. */
2207 if (!cv) goto not_found;
2208 } else if (!(AMGf_noright & flags) && SvAMAGIC(right)
2209 && (stash = SvSTASH(SvRV(right)))
2210 && (mg = mg_find((const SV *)stash, PERL_MAGIC_overload_table))
2211 && (cvp = (AMT_AMAGIC((AMT*)mg->mg_ptr)
2212 ? (amtp = (AMT*)mg->mg_ptr)->table
2214 && (cv = cvp[off=method])) { /* Method for right
2217 } else if (((ocvp && oamtp->fallback > AMGfallNEVER
2218 && (cvp=ocvp) && (lr = -1))
2219 || (cvp && amtp->fallback > AMGfallNEVER && (lr=1)))
2220 && !(flags & AMGf_unary)) {
2221 /* We look for substitution for
2222 * comparison operations and
2224 if (method==concat_amg || method==concat_ass_amg
2225 || method==repeat_amg || method==repeat_ass_amg) {
2226 return NULL; /* Delegate operation to string conversion */
2247 if ((off != -1) && (cv = cvp[off]))
2252 not_found: /* No method found, either report or croak */
2260 return left; /* Delegate operation to standard mechanisms. */
2263 if (ocvp && (cv=ocvp[nomethod_amg])) { /* Call report method */
2264 notfound = 1; lr = -1;
2265 } else if (cvp && (cv=cvp[nomethod_amg])) {
2266 notfound = 1; lr = 1;
2267 } else if ((amtp && amtp->fallback >= AMGfallYES) && !DEBUG_o_TEST) {
2268 /* Skip generating the "no method found" message. */
2272 if (off==-1) off=method;
2273 msg = sv_2mortal(Perl_newSVpvf(aTHX_
2274 "Operation \"%s\": no method found,%sargument %s%s%s%s",
2275 AMG_id2name(method + assignshift),
2276 (flags & AMGf_unary ? " " : "\n\tleft "),
2278 "in overloaded package ":
2279 "has no overloaded magic",
2281 HvNAME_get(SvSTASH(SvRV(left))):
2284 ",\n\tright argument in overloaded package ":
2287 : ",\n\tright argument has no overloaded magic"),
2289 HvNAME_get(SvSTASH(SvRV(right))):
2291 if (amtp && amtp->fallback >= AMGfallYES) {
2292 DEBUG_o( Perl_deb(aTHX_ "%s", SvPVX_const(msg)) );
2294 Perl_croak(aTHX_ "%"SVf, SVfARG(msg));
2298 force_cpy = force_cpy || assign;
2303 DEBUG_o(Perl_deb(aTHX_
2304 "Overloaded operator \"%s\"%s%s%s:\n\tmethod%s found%s in package %s%s\n",
2306 method+assignshift==off? "" :
2308 method+assignshift==off? "" :
2309 AMG_id2name(method+assignshift),
2310 method+assignshift==off? "" : "\")",
2311 flags & AMGf_unary? "" :
2312 lr==1 ? " for right argument": " for left argument",
2313 flags & AMGf_unary? " for argument" : "",
2314 stash ? HvNAME_get(stash) : "null",
2315 fl? ",\n\tassignment variant used": "") );
2318 /* Since we use shallow copy during assignment, we need
2319 * to dublicate the contents, probably calling user-supplied
2320 * version of copy operator
2322 /* We need to copy in following cases:
2323 * a) Assignment form was called.
2324 * assignshift==1, assign==T, method + 1 == off
2325 * b) Increment or decrement, called directly.
2326 * assignshift==0, assign==0, method + 0 == off
2327 * c) Increment or decrement, translated to assignment add/subtr.
2328 * assignshift==0, assign==T,
2330 * d) Increment or decrement, translated to nomethod.
2331 * assignshift==0, assign==0,
2333 * e) Assignment form translated to nomethod.
2334 * assignshift==1, assign==T, method + 1 != off
2337 /* off is method, method+assignshift, or a result of opcode substitution.
2338 * In the latter case assignshift==0, so only notfound case is important.
2340 if (( (method + assignshift == off)
2341 && (assign || (method == inc_amg) || (method == dec_amg)))
2344 /* newSVsv does not behave as advertised, so we copy missing
2345 * information by hand */
2346 SV *tmpRef = SvRV(left);
2348 if (SvREFCNT(tmpRef) > 1 && (rv_copy = AMG_CALLun(left,copy))) {
2349 SvRV_set(left, rv_copy);
2351 SvREFCNT_dec(tmpRef);
2359 const bool oldcatch = CATCH_GET;
2362 Zero(&myop, 1, BINOP);
2363 myop.op_last = (OP *) &myop;
2364 myop.op_next = NULL;
2365 myop.op_flags = OPf_WANT_SCALAR | OPf_STACKED;
2367 PUSHSTACKi(PERLSI_OVERLOAD);
2370 PL_op = (OP *) &myop;
2371 if (PERLDB_SUB && PL_curstash != PL_debstash)
2372 PL_op->op_private |= OPpENTERSUB_DB;
2376 EXTEND(SP, notfound + 5);
2377 PUSHs(lr>0? right: left);
2378 PUSHs(lr>0? left: right);
2379 PUSHs( lr > 0 ? &PL_sv_yes : ( assign ? &PL_sv_undef : &PL_sv_no ));
2381 PUSHs(newSVpvn_flags(AMG_id2name(method + assignshift),
2382 AMG_id2namelen(method + assignshift), SVs_TEMP));
2384 PUSHs(MUTABLE_SV(cv));
2387 if ((PL_op = PL_ppaddr[OP_ENTERSUB](aTHX)))
2395 CATCH_SET(oldcatch);
2402 ans=SvIV(res)<=0; break;
2405 ans=SvIV(res)<0; break;
2408 ans=SvIV(res)>=0; break;
2411 ans=SvIV(res)>0; break;
2414 ans=SvIV(res)==0; break;
2417 ans=SvIV(res)!=0; break;
2420 SvSetSV(left,res); return left;
2422 ans=!SvTRUE(res); break;
2427 } else if (method==copy_amg) {
2429 Perl_croak(aTHX_ "Copy method did not return a reference");
2431 return SvREFCNT_inc(SvRV(res));
2439 =for apidoc is_gv_magical_sv
2441 Returns C<TRUE> if given the name of a magical GV.
2443 Currently only useful internally when determining if a GV should be
2444 created even in rvalue contexts.
2446 C<flags> is not used at present but available for future extension to
2447 allow selecting particular classes of magical variable.
2449 Currently assumes that C<name> is NUL terminated (as well as len being valid).
2450 This assumption is met by all callers within the perl core, which all pass
2451 pointers returned by SvPV.
2457 Perl_is_gv_magical_sv(pTHX_ SV *const name_sv, U32 flags)
2460 const char *const name = SvPV_const(name_sv, len);
2462 PERL_UNUSED_ARG(flags);
2463 PERL_ARGS_ASSERT_IS_GV_MAGICAL_SV;
2466 const char * const name1 = name + 1;
2469 if (len == 3 && name[1] == 'S' && name[2] == 'A')
2473 if (len == 8 && strEQ(name1, "VERLOAD"))
2477 if (len == 3 && name[1] == 'I' && name[2] == 'G')
2480 /* Using ${^...} variables is likely to be sufficiently rare that
2481 it seems sensible to avoid the space hit of also checking the
2483 case '\017': /* ${^OPEN} */
2484 if (strEQ(name1, "PEN"))
2487 case '\024': /* ${^TAINT} */
2488 if (strEQ(name1, "AINT"))
2491 case '\025': /* ${^UNICODE} */
2492 if (strEQ(name1, "NICODE"))
2494 if (strEQ(name1, "TF8LOCALE"))
2497 case '\027': /* ${^WARNING_BITS} */
2498 if (strEQ(name1, "ARNING_BITS"))
2511 const char *end = name + len;
2512 while (--end > name) {
2520 /* Because we're already assuming that name is NUL terminated
2521 below, we can treat an empty name as "\0" */
2547 case '\001': /* $^A */
2548 case '\003': /* $^C */
2549 case '\004': /* $^D */
2550 case '\005': /* $^E */
2551 case '\006': /* $^F */
2552 case '\010': /* $^H */
2553 case '\011': /* $^I, NOT \t in EBCDIC */
2554 case '\014': /* $^L */
2555 case '\016': /* $^N */
2556 case '\017': /* $^O */
2557 case '\020': /* $^P */
2558 case '\023': /* $^S */
2559 case '\024': /* $^T */
2560 case '\026': /* $^V */
2561 case '\027': /* $^W */
2581 Perl_gv_name_set(pTHX_ GV *gv, const char *name, U32 len, U32 flags)
2586 PERL_ARGS_ASSERT_GV_NAME_SET;
2587 PERL_UNUSED_ARG(flags);
2590 Perl_croak(aTHX_ "panic: gv name too long (%"UVuf")", (UV) len);
2592 if (!(flags & GV_ADD) && GvNAME_HEK(gv)) {
2593 unshare_hek(GvNAME_HEK(gv));
2596 PERL_HASH(hash, name, len);
2597 GvNAME_HEK(gv) = share_hek(name, len, hash);
2601 =for apidoc gv_try_downgrade
2603 If the typeglob C<gv> can be expressed more succinctly, by having
2604 something other than a real GV in its place in the stash, replace it
2605 with the optimised form. Basic requirements for this are that C<gv>
2606 is a real typeglob, is sufficiently ordinary, and is only referenced
2607 from its package. This function is meant to be used when a GV has been
2608 looked up in part to see what was there, causing upgrading, but based
2609 on what was found it turns out that the real GV isn't required after all.
2611 If C<gv> is a completely empty typeglob, it is deleted from the stash.
2613 If C<gv> is a typeglob containing only a sufficiently-ordinary constant
2614 sub, the typeglob is replaced with a scalar-reference placeholder that
2615 more compactly represents the same thing.
2621 Perl_gv_try_downgrade(pTHX_ GV *gv)
2627 PERL_ARGS_ASSERT_GV_TRY_DOWNGRADE;
2629 /* XXX Why and where does this leave dangling pointers during global
2631 if (PL_phase == PERL_PHASE_DESTRUCT) return;
2633 if (!(SvREFCNT(gv) == 1 && SvTYPE(gv) == SVt_PVGV && !SvFAKE(gv) &&
2634 !SvOBJECT(gv) && !SvREADONLY(gv) &&
2635 isGV_with_GP(gv) && GvGP(gv) &&
2636 !GvINTRO(gv) && GvREFCNT(gv) == 1 &&
2637 !GvSV(gv) && !GvAV(gv) && !GvHV(gv) && !GvIOp(gv) && !GvFORM(gv) &&
2638 GvEGVx(gv) == gv && (stash = GvSTASH(gv))))
2640 if (SvMAGICAL(gv)) {
2642 /* only backref magic is allowed */
2643 if (SvGMAGICAL(gv) || SvSMAGICAL(gv))
2645 for (mg = SvMAGIC(gv); mg; mg = mg->mg_moremagic) {
2646 if (mg->mg_type != PERL_MAGIC_backref)
2652 HEK *gvnhek = GvNAME_HEK(gv);
2653 (void)hv_delete(stash, HEK_KEY(gvnhek),
2654 HEK_UTF8(gvnhek) ? -HEK_LEN(gvnhek) : HEK_LEN(gvnhek), G_DISCARD);
2655 } else if (GvMULTI(gv) && cv &&
2656 !SvOBJECT(cv) && !SvMAGICAL(cv) && !SvREADONLY(cv) &&
2657 CvSTASH(cv) == stash && CvGV(cv) == gv &&
2658 CvCONST(cv) && !CvMETHOD(cv) && !CvLVALUE(cv) && !CvUNIQUE(cv) &&
2659 !CvNODEBUG(cv) && !CvCLONE(cv) && !CvCLONED(cv) && !CvANON(cv) &&
2660 (namehek = GvNAME_HEK(gv)) &&
2661 (gvp = hv_fetch(stash, HEK_KEY(namehek),
2662 HEK_LEN(namehek)*(HEK_UTF8(namehek) ? -1 : 1), 0)) &&
2664 SV *value = SvREFCNT_inc(CvXSUBANY(cv).any_ptr);
2668 SvFLAGS(gv) = SVt_IV|SVf_ROK;
2669 SvANY(gv) = (XPVGV*)((char*)&(gv->sv_u.svu_iv) -
2670 STRUCT_OFFSET(XPVIV, xiv_iv));
2671 SvRV_set(gv, value);
2677 * c-indentation-style: bsd
2679 * indent-tabs-mode: t
2682 * ex: set ts=8 sts=4 sw=4 noet: