3 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
4 * 2005, 2006, 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 * "The roots of those mountains must be roots indeed; there must be
13 * great secrets buried there which have not been discovered since the
14 * beginning." --Gandalf, relating Gollum's story
17 /* This file contains the code that implements the functions in Perl's
18 * UNIVERSAL package, such as UNIVERSAL->can().
22 #define PERL_IN_UNIVERSAL_C
26 #include "perliol.h" /* For the PERLIO_F_XXX */
30 * Contributed by Graham Barr <Graham.Barr@tiuk.ti.com>
31 * The main guts of traverse_isa was actually copied from gv_fetchmeth
35 S_isa_lookup(pTHX_ HV *stash, const char *name, HV* name_stash,
46 /* A stash/class can go by many names (ie. User == main::User), so
47 we compare the stash itself just in case */
48 if (name_stash && (stash == name_stash))
51 hvname = HvNAME_get(stash);
53 if (strEQ(hvname, name))
56 if (strEQ(name, "UNIVERSAL"))
60 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
63 gvp = (GV**)hv_fetchs(stash, "::ISA::CACHE::", FALSE);
65 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (subgen = GvSV(gv))
68 if (SvIV(subgen) == (IV)PL_sub_generation) {
70 SV** const svp = (SV**)hv_fetch(hv, name, len, FALSE);
71 if (svp && (sv = *svp) != (SV*)&PL_sv_undef) {
72 DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
74 return (sv == &PL_sv_yes);
78 DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
81 sv_setiv(subgen, PL_sub_generation);
85 gvp = (GV**)hv_fetchs(stash, "ISA", FALSE);
87 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
89 gvp = (GV**)hv_fetchs(stash, "::ISA::CACHE::", TRUE);
93 if (SvTYPE(gv) != SVt_PVGV)
94 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
99 subgen = newSViv(PL_sub_generation);
104 SV** svp = AvARRAY(av);
105 /* NOTE: No support for tied ISA */
106 I32 items = AvFILLp(av) + 1;
108 SV* const sv = *svp++;
109 HV* const basestash = gv_stashsv(sv, FALSE);
111 if (ckWARN(WARN_MISC))
112 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
113 "Can't locate package %"SVf" for @%s::ISA",
117 if (isa_lookup(basestash, name, name_stash, len, level + 1)) {
118 (void)hv_store(hv,name,len,&PL_sv_yes,0);
122 (void)hv_store(hv,name,len,&PL_sv_no,0);
129 =head1 SV Manipulation Functions
131 =for apidoc sv_derived_from
133 Returns a boolean indicating whether the SV is derived from the specified class
134 I<at the C level>. To check derivation at the Perl level, call C<isa()> as a
141 Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
151 type = sv_reftype(sv,0);
152 if (type && strEQ(type,name))
154 stash = SvOBJECT(sv) ? SvSTASH(sv) : NULL;
157 stash = gv_stashsv(sv, FALSE);
161 HV * const name_stash = gv_stashpv(name, FALSE);
162 return isa_lookup(stash, name, name_stash, strlen(name), 0);
172 Returns a boolean indicating whether the SV performs a specific, named role.
173 The SV can be a Perl object or the name of a Perl class.
181 Perl_sv_does(pTHX_ SV *sv, const char *name)
183 const char *classname;
192 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
193 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
196 if (sv_isobject(sv)) {
197 classname = sv_reftype(SvRV(sv),TRUE);
199 classname = SvPV(sv,PL_na);
202 if (strEQ(name,classname))
207 XPUSHs(sv_2mortal(newSVpv(name, 0)));
210 call_method("isa", G_SCALAR);
213 does_it = SvTRUE( TOPs );
220 PERL_XS_EXPORT_C void XS_UNIVERSAL_isa(pTHX_ CV *cv);
221 PERL_XS_EXPORT_C void XS_UNIVERSAL_can(pTHX_ CV *cv);
222 PERL_XS_EXPORT_C void XS_UNIVERSAL_DOES(pTHX_ CV *cv);
223 PERL_XS_EXPORT_C void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
225 XS(XS_version_stringify);
226 XS(XS_version_numify);
227 XS(XS_version_normal);
229 XS(XS_version_boolean);
230 #ifdef HASATTRIBUTE_NORETURN
231 XS(XS_version_noop) __attribute__noreturn__;
235 XS(XS_version_is_alpha);
242 XS(XS_utf8_downgrade);
243 XS(XS_utf8_unicode_to_native);
244 XS(XS_utf8_native_to_unicode);
245 XS(XS_Internals_SvREADONLY);
246 XS(XS_Internals_SvREFCNT);
247 XS(XS_Internals_hv_clear_placehold);
248 XS(XS_PerlIO_get_layers);
249 XS(XS_Regexp_DESTROY);
250 XS(XS_Internals_hash_seed);
251 XS(XS_Internals_rehash_seed);
252 XS(XS_Internals_HvREHASH);
253 XS(XS_Internals_inc_sub_generation);
256 Perl_boot_core_UNIVERSAL(pTHX)
259 static const char file[] = __FILE__;
261 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
262 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
263 newXS("UNIVERSAL::DOES", XS_UNIVERSAL_DOES, file);
264 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
266 /* register the overloading (type 'A') magic */
267 PL_amagic_generation++;
268 /* Make it findable via fetchmethod */
269 newXS("version::()", XS_version_noop, file);
270 newXS("version::new", XS_version_new, file);
271 newXS("version::(\"\"", XS_version_stringify, file);
272 newXS("version::stringify", XS_version_stringify, file);
273 newXS("version::(0+", XS_version_numify, file);
274 newXS("version::numify", XS_version_numify, file);
275 newXS("version::normal", XS_version_normal, file);
276 newXS("version::(cmp", XS_version_vcmp, file);
277 newXS("version::(<=>", XS_version_vcmp, file);
278 newXS("version::vcmp", XS_version_vcmp, file);
279 newXS("version::(bool", XS_version_boolean, file);
280 newXS("version::boolean", XS_version_boolean, file);
281 newXS("version::(nomethod", XS_version_noop, file);
282 newXS("version::noop", XS_version_noop, file);
283 newXS("version::is_alpha", XS_version_is_alpha, file);
284 newXS("version::qv", XS_version_qv, file);
286 newXS("utf8::is_utf8", XS_utf8_is_utf8, file);
287 newXS("utf8::valid", XS_utf8_valid, file);
288 newXS("utf8::encode", XS_utf8_encode, file);
289 newXS("utf8::decode", XS_utf8_decode, file);
290 newXS("utf8::upgrade", XS_utf8_upgrade, file);
291 newXS("utf8::downgrade", XS_utf8_downgrade, file);
292 newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
293 newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
294 newXSproto("Internals::SvREADONLY",XS_Internals_SvREADONLY, file, "\\[$%@];$");
295 newXSproto("Internals::SvREFCNT",XS_Internals_SvREFCNT, file, "\\[$%@];$");
296 newXSproto("Internals::hv_clear_placeholders",
297 XS_Internals_hv_clear_placehold, file, "\\%");
298 newXSproto("PerlIO::get_layers",
299 XS_PerlIO_get_layers, file, "*;@");
300 newXS("Regexp::DESTROY", XS_Regexp_DESTROY, file);
301 newXSproto("Internals::hash_seed",XS_Internals_hash_seed, file, "");
302 newXSproto("Internals::rehash_seed",XS_Internals_rehash_seed, file, "");
303 newXSproto("Internals::HvREHASH", XS_Internals_HvREHASH, file, "\\%");
304 newXSproto("Internals::inc_sub_generation",XS_Internals_inc_sub_generation,
315 Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
317 SV * const sv = ST(0);
322 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
323 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
326 name = SvPV_nolen_const(ST(1));
328 ST(0) = boolSV(sv_derived_from(sv, name));
343 Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
349 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
350 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
353 name = SvPV_nolen_const(ST(1));
362 pkg = gv_stashsv(sv, FALSE);
366 GV * const gv = gv_fetchmethod_autoload(pkg, name, FALSE);
368 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
375 XS(XS_UNIVERSAL_DOES)
381 Perl_croak(aTHX_ "Usage: invocant->does(kind)");
383 SV * const sv = ST(0);
386 name = SvPV_nolen_const(ST(1));
387 if (sv_does( sv, name ))
394 XS(XS_UNIVERSAL_VERSION)
405 sv = (SV*)SvRV(ST(0));
407 Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
411 pkg = gv_stashsv(ST(0), FALSE);
414 gvp = pkg ? (GV**)hv_fetchs(pkg, "VERSION", FALSE) : NULL;
416 if (gvp && isGV(gv = *gvp) && (sv = GvSV(gv)) && SvOK(sv)) {
417 SV * const nsv = sv_newmortal();
420 if ( !sv_derived_from(sv, "version"))
425 sv = (SV*)&PL_sv_undef;
434 const char * const name = HvNAME_get(pkg);
436 "%s does not define $%s::VERSION--version check failed",
440 "%s defines neither package nor VERSION--version check failed",
441 SvPVx_nolen_const(ST(0)) );
445 if ( !sv_derived_from(req, "version")) {
446 /* req may very well be R/O, so create a new object */
447 SV * const nsv = sv_newmortal();
453 if ( vcmp( req, sv ) > 0 )
454 Perl_croak(aTHX_ "%s version %"SVf" (%"SVf") required--"
455 "this is only version %"SVf" (%"SVf")", HvNAME_get(pkg),
462 if ( SvOK(sv) && sv_derived_from(sv, "version") ) {
476 Perl_croak(aTHX_ "Usage: version::new(class, version)");
481 const char * const classname =
482 sv_isobject(ST(0)) /* get the class if called as an object method */
483 ? HvNAME(SvSTASH(SvRV(ST(0))))
484 : (char *)SvPV_nolen(ST(0));
486 if ( items == 1 || vs == &PL_sv_undef ) { /* no param or explicit undef */
487 /* create empty object */
491 else if ( items == 3 ) {
493 Perl_sv_setpvf(aTHX_ vs,"v%s",SvPV_nolen_const(ST(2)));
496 rv = new_version(vs);
497 if ( strcmp(classname,"version") != 0 ) /* inherited new() */
498 sv_bless(rv, gv_stashpv(classname,TRUE));
500 PUSHs(sv_2mortal(rv));
506 XS(XS_version_stringify)
511 Perl_croak(aTHX_ "Usage: version::stringify(lobj, ...)");
516 if (sv_derived_from(ST(0), "version")) {
520 Perl_croak(aTHX_ "lobj is not of type version");
522 PUSHs(sv_2mortal(vstringify(lobj)));
529 XS(XS_version_numify)
534 Perl_croak(aTHX_ "Usage: version::numify(lobj, ...)");
539 if (sv_derived_from(ST(0), "version")) {
543 Perl_croak(aTHX_ "lobj is not of type version");
545 PUSHs(sv_2mortal(vnumify(lobj)));
552 XS(XS_version_normal)
557 Perl_croak(aTHX_ "Usage: version::normal(lobj, ...)");
562 if (sv_derived_from(ST(0), "version")) {
566 Perl_croak(aTHX_ "lobj is not of type version");
568 PUSHs(sv_2mortal(vnormal(lobj)));
580 Perl_croak(aTHX_ "Usage: version::vcmp(lobj, ...)");
585 if (sv_derived_from(ST(0), "version")) {
589 Perl_croak(aTHX_ "lobj is not of type version");
595 const IV swap = (IV)SvIV(ST(2));
597 if ( ! sv_derived_from(robj, "version") )
599 robj = new_version(robj);
605 rs = newSViv(vcmp(rvs,lobj));
609 rs = newSViv(vcmp(lobj,rvs));
612 PUSHs(sv_2mortal(rs));
620 XS(XS_version_boolean)
625 Perl_croak(aTHX_ "Usage: version::boolean(lobj, ...)");
627 if (sv_derived_from(ST(0), "version")) {
628 SV * const lobj = SvRV(ST(0));
629 SV * const rs = newSViv( vcmp(lobj,new_version(newSVpvs("0"))) );
630 PUSHs(sv_2mortal(rs));
635 Perl_croak(aTHX_ "lobj is not of type version");
643 Perl_croak(aTHX_ "Usage: version::noop(lobj, ...)");
644 if (sv_derived_from(ST(0), "version"))
645 Perl_croak(aTHX_ "operation not supported with version object");
647 Perl_croak(aTHX_ "lobj is not of type version");
648 #ifndef HASATTRIBUTE_NORETURN
653 XS(XS_version_is_alpha)
658 Perl_croak(aTHX_ "Usage: version::is_alpha(lobj)");
660 if (sv_derived_from(ST(0), "version")) {
661 SV * const lobj = ST(0);
662 if ( hv_exists((HV*)SvRV(lobj), "alpha", 5 ) )
670 Perl_croak(aTHX_ "lobj is not of type version");
678 Perl_croak(aTHX_ "Usage: version::qv(ver)");
682 if ( !SvVOK(ver) ) { /* only need to do with if not already v-string */
683 SV * const vs = sv_newmortal();
685 if ( SvNOK(ver) ) /* may get too much accuracy */
688 const STRLEN len = my_snprintf(tbuf, sizeof(tbuf), "%.9"NVgf, SvNVX(ver));
689 version = savepvn(tbuf, len);
693 version = savesvpv(ver);
695 (void)scan_version(version,vs,TRUE);
702 PUSHs(sv_2mortal(new_version(ver)));
715 Perl_croak(aTHX_ "Usage: utf8::is_utf8(sv)");
717 const SV * const sv = ST(0);
731 Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
733 SV * const sv = ST(0);
735 const char * const s = SvPV_const(sv,len);
736 if (!SvUTF8(sv) || is_utf8_string((const U8*)s,len))
749 Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
750 sv_utf8_encode(ST(0));
759 Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
761 SV * const sv = ST(0);
762 const bool RETVAL = sv_utf8_decode(sv);
763 ST(0) = boolSV(RETVAL);
774 Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
776 SV * const sv = ST(0);
780 RETVAL = sv_utf8_upgrade(sv);
781 XSprePUSH; PUSHi((IV)RETVAL);
786 XS(XS_utf8_downgrade)
790 if (items < 1 || items > 2)
791 Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
793 SV * const sv = ST(0);
794 const bool failok = (items < 2) ? 0 : (int)SvIV(ST(1));
795 const bool RETVAL = sv_utf8_downgrade(sv, failok);
797 ST(0) = boolSV(RETVAL);
803 XS(XS_utf8_native_to_unicode)
807 const UV uv = SvUV(ST(0));
810 Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
812 ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
816 XS(XS_utf8_unicode_to_native)
820 const UV uv = SvUV(ST(0));
823 Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
825 ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
829 XS(XS_Internals_SvREADONLY) /* This is dangerous stuff. */
833 SV * const sv = SvRV(ST(0));
841 else if (items == 2) {
847 /* I hope you really know what you are doing. */
852 XSRETURN_UNDEF; /* Can't happen. */
855 XS(XS_Internals_SvREFCNT) /* This is dangerous stuff. */
859 SV * const sv = SvRV(ST(0));
862 XSRETURN_IV(SvREFCNT(sv) - 1); /* Minus the ref created for us. */
863 else if (items == 2) {
864 /* I hope you really know what you are doing. */
865 SvREFCNT(sv) = SvIV(ST(1));
866 XSRETURN_IV(SvREFCNT(sv));
868 XSRETURN_UNDEF; /* Can't happen. */
871 XS(XS_Internals_hv_clear_placehold)
877 Perl_croak(aTHX_ "Usage: UNIVERSAL::hv_clear_placeholders(hv)");
879 HV * const hv = (HV *) SvRV(ST(0));
880 hv_clear_placeholders(hv);
885 XS(XS_Regexp_DESTROY)
891 XS(XS_PerlIO_get_layers)
895 if (items < 1 || items % 2 == 0)
896 Perl_croak(aTHX_ "Usage: PerlIO_get_layers(filehandle[,args])");
903 bool details = FALSE;
907 for (svp = MARK + 2; svp <= SP; svp += 2) {
908 SV * const * const varp = svp;
909 SV * const * const valp = svp + 1;
911 const char * const key = SvPV_const(*varp, klen);
915 if (klen == 5 && memEQ(key, "input", 5)) {
916 input = SvTRUE(*valp);
921 if (klen == 6 && memEQ(key, "output", 6)) {
922 input = !SvTRUE(*valp);
927 if (klen == 7 && memEQ(key, "details", 7)) {
928 details = SvTRUE(*valp);
935 "get_layers: unknown argument '%s'",
947 if (SvROK(sv) && isGV(SvRV(sv)))
950 gv = gv_fetchsv(sv, 0, SVt_PVIO);
953 if (gv && (io = GvIO(gv))) {
955 AV* const av = PerlIO_get_layers(aTHX_ input ?
956 IoIFP(io) : IoOFP(io));
958 const I32 last = av_len(av);
961 for (i = last; i >= 0; i -= 3) {
962 SV * const * const namsvp = av_fetch(av, i - 2, FALSE);
963 SV * const * const argsvp = av_fetch(av, i - 1, FALSE);
964 SV * const * const flgsvp = av_fetch(av, i, FALSE);
966 const bool namok = namsvp && *namsvp && SvPOK(*namsvp);
967 const bool argok = argsvp && *argsvp && SvPOK(*argsvp);
968 const bool flgok = flgsvp && *flgsvp && SvIOK(*flgsvp);
972 ? newSVpvn(SvPVX_const(*namsvp), SvCUR(*namsvp))
975 ? newSVpvn(SvPVX_const(*argsvp), SvCUR(*argsvp))
978 XPUSHi(SvIVX(*flgsvp));
980 XPUSHs(&PL_sv_undef);
985 XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf"(%"SVf")",
989 XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf,
992 XPUSHs(&PL_sv_undef);
995 const IV flags = SvIVX(*flgsvp);
997 if (flags & PERLIO_F_UTF8) {
998 XPUSHs(newSVpvs("utf8"));
1015 XS(XS_Internals_hash_seed)
1018 /* Using dXSARGS would also have dITEM and dSP,
1019 * which define 2 unused local variables. */
1021 PERL_UNUSED_ARG(cv);
1022 PERL_UNUSED_VAR(mark);
1023 XSRETURN_UV(PERL_HASH_SEED);
1026 XS(XS_Internals_rehash_seed)
1029 /* Using dXSARGS would also have dITEM and dSP,
1030 * which define 2 unused local variables. */
1032 PERL_UNUSED_ARG(cv);
1033 PERL_UNUSED_VAR(mark);
1034 XSRETURN_UV(PL_rehash_seed);
1037 XS(XS_Internals_HvREHASH) /* Subject to change */
1042 const HV * const hv = (HV *) SvRV(ST(0));
1043 if (items == 1 && SvTYPE(hv) == SVt_PVHV) {
1050 Perl_croak(aTHX_ "Internals::HvREHASH $hashref");
1053 XS(XS_Internals_inc_sub_generation)
1056 /* Using dXSARGS would also have dITEM and dSP,
1057 * which define 2 unused local variables. */
1059 PERL_UNUSED_ARG(cv);
1060 PERL_UNUSED_VAR(mark);
1061 ++PL_sub_generation;
1067 * c-indentation-style: bsd
1069 * indent-tabs-mode: t
1072 * ex: set ts=8 sts=4 sw=4 noet: