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, const HV* const 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 && ((const HV *)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) {
69 SV** const svp = (SV**)hv_fetch(hv, name, len, FALSE);
72 if (sv != &PL_sv_undef)
73 DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
75 return (sv == &PL_sv_yes);
79 DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
82 sv_setiv(subgen, PL_sub_generation);
86 gvp = (GV**)hv_fetchs(stash, "ISA", FALSE);
88 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
90 gvp = (GV**)hv_fetchs(stash, "::ISA::CACHE::", TRUE);
94 if (SvTYPE(gv) != SVt_PVGV)
95 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
100 subgen = newSViv(PL_sub_generation);
105 SV** svp = AvARRAY(av);
106 /* NOTE: No support for tied ISA */
107 I32 items = AvFILLp(av) + 1;
109 SV* const sv = *svp++;
110 HV* const basestash = gv_stashsv(sv, FALSE);
112 if (ckWARN(WARN_MISC))
113 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
114 "Can't locate package %"SVf" for @%s::ISA",
118 if (isa_lookup(basestash, name, name_stash, len, level + 1)) {
119 (void)hv_store(hv,name,len,&PL_sv_yes,0);
123 (void)hv_store(hv,name,len,&PL_sv_no,0);
130 =head1 SV Manipulation Functions
132 =for apidoc sv_derived_from
134 Returns a boolean indicating whether the SV is derived from the specified class
135 I<at the C level>. To check derivation at the Perl level, call C<isa()> as a
142 Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
152 type = sv_reftype(sv,0);
153 if (type && strEQ(type,name))
155 stash = SvOBJECT(sv) ? SvSTASH(sv) : NULL;
158 stash = gv_stashsv(sv, FALSE);
162 HV * const name_stash = gv_stashpv(name, FALSE);
163 return isa_lookup(stash, name, name_stash, strlen(name), 0);
173 Returns a boolean indicating whether the SV performs a specific, named role.
174 The SV can be a Perl object or the name of a Perl class.
182 Perl_sv_does(pTHX_ SV *sv, const char *name)
184 const char *classname;
193 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
194 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
197 if (sv_isobject(sv)) {
198 classname = sv_reftype(SvRV(sv),TRUE);
200 classname = SvPV(sv,PL_na);
203 if (strEQ(name,classname))
208 XPUSHs(sv_2mortal(newSVpv(name, 0)));
211 call_method("isa", G_SCALAR);
214 does_it = SvTRUE( TOPs );
221 PERL_XS_EXPORT_C void XS_UNIVERSAL_isa(pTHX_ CV *cv);
222 PERL_XS_EXPORT_C void XS_UNIVERSAL_can(pTHX_ CV *cv);
223 PERL_XS_EXPORT_C void XS_UNIVERSAL_DOES(pTHX_ CV *cv);
224 PERL_XS_EXPORT_C void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
226 XS(XS_version_stringify);
227 XS(XS_version_numify);
228 XS(XS_version_normal);
230 XS(XS_version_boolean);
231 #ifdef HASATTRIBUTE_NORETURN
232 XS(XS_version_noop) __attribute__noreturn__;
236 XS(XS_version_is_alpha);
243 XS(XS_utf8_downgrade);
244 XS(XS_utf8_unicode_to_native);
245 XS(XS_utf8_native_to_unicode);
246 XS(XS_Internals_SvREADONLY);
247 XS(XS_Internals_SvREFCNT);
248 XS(XS_Internals_hv_clear_placehold);
249 XS(XS_PerlIO_get_layers);
250 XS(XS_Regexp_DESTROY);
251 XS(XS_Internals_hash_seed);
252 XS(XS_Internals_rehash_seed);
253 XS(XS_Internals_HvREHASH);
254 XS(XS_Internals_inc_sub_generation);
257 Perl_boot_core_UNIVERSAL(pTHX)
260 static const char file[] = __FILE__;
262 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
263 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
264 newXS("UNIVERSAL::DOES", XS_UNIVERSAL_DOES, file);
265 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
267 /* register the overloading (type 'A') magic */
268 PL_amagic_generation++;
269 /* Make it findable via fetchmethod */
270 newXS("version::()", XS_version_noop, file);
271 newXS("version::new", XS_version_new, file);
272 newXS("version::(\"\"", XS_version_stringify, file);
273 newXS("version::stringify", XS_version_stringify, file);
274 newXS("version::(0+", XS_version_numify, file);
275 newXS("version::numify", XS_version_numify, file);
276 newXS("version::normal", XS_version_normal, file);
277 newXS("version::(cmp", XS_version_vcmp, file);
278 newXS("version::(<=>", XS_version_vcmp, file);
279 newXS("version::vcmp", XS_version_vcmp, file);
280 newXS("version::(bool", XS_version_boolean, file);
281 newXS("version::boolean", XS_version_boolean, file);
282 newXS("version::(nomethod", XS_version_noop, file);
283 newXS("version::noop", XS_version_noop, file);
284 newXS("version::is_alpha", XS_version_is_alpha, file);
285 newXS("version::qv", XS_version_qv, file);
287 newXS("utf8::is_utf8", XS_utf8_is_utf8, file);
288 newXS("utf8::valid", XS_utf8_valid, file);
289 newXS("utf8::encode", XS_utf8_encode, file);
290 newXS("utf8::decode", XS_utf8_decode, file);
291 newXS("utf8::upgrade", XS_utf8_upgrade, file);
292 newXS("utf8::downgrade", XS_utf8_downgrade, file);
293 newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
294 newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
295 newXSproto("Internals::SvREADONLY",XS_Internals_SvREADONLY, file, "\\[$%@];$");
296 newXSproto("Internals::SvREFCNT",XS_Internals_SvREFCNT, file, "\\[$%@];$");
297 newXSproto("Internals::hv_clear_placeholders",
298 XS_Internals_hv_clear_placehold, file, "\\%");
299 newXSproto("PerlIO::get_layers",
300 XS_PerlIO_get_layers, file, "*;@");
301 newXS("Regexp::DESTROY", XS_Regexp_DESTROY, file);
302 newXSproto("Internals::hash_seed",XS_Internals_hash_seed, file, "");
303 newXSproto("Internals::rehash_seed",XS_Internals_rehash_seed, file, "");
304 newXSproto("Internals::HvREHASH", XS_Internals_HvREHASH, file, "\\%");
305 newXSproto("Internals::inc_sub_generation",XS_Internals_inc_sub_generation,
316 Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
318 SV * const sv = ST(0);
323 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
324 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
327 name = SvPV_nolen_const(ST(1));
329 ST(0) = boolSV(sv_derived_from(sv, name));
344 Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
350 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
351 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
354 name = SvPV_nolen_const(ST(1));
363 pkg = gv_stashsv(sv, FALSE);
367 GV * const gv = gv_fetchmethod_autoload(pkg, name, FALSE);
369 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
376 XS(XS_UNIVERSAL_DOES)
382 Perl_croak(aTHX_ "Usage: invocant->does(kind)");
384 SV * const sv = ST(0);
387 name = SvPV_nolen_const(ST(1));
388 if (sv_does( sv, name ))
395 XS(XS_UNIVERSAL_VERSION)
406 sv = (SV*)SvRV(ST(0));
408 Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
412 pkg = gv_stashsv(ST(0), FALSE);
415 gvp = pkg ? (GV**)hv_fetchs(pkg, "VERSION", FALSE) : NULL;
417 if (gvp && isGV(gv = *gvp) && (sv = GvSV(gv)) && SvOK(sv)) {
418 SV * const nsv = sv_newmortal();
421 if ( !sv_derived_from(sv, "version"))
426 sv = (SV*)&PL_sv_undef;
435 const char * const name = HvNAME_get(pkg);
437 "%s does not define $%s::VERSION--version check failed",
441 "%s defines neither package nor VERSION--version check failed",
442 SvPVx_nolen_const(ST(0)) );
446 if ( !sv_derived_from(req, "version")) {
447 /* req may very well be R/O, so create a new object */
448 SV * const nsv = sv_newmortal();
454 if ( vcmp( req, sv ) > 0 )
455 Perl_croak(aTHX_ "%s version %"SVf" (%"SVf") required--"
456 "this is only version %"SVf" (%"SVf")", HvNAME_get(pkg),
463 if ( SvOK(sv) && sv_derived_from(sv, "version") ) {
477 Perl_croak(aTHX_ "Usage: version::new(class, version)");
482 const char * const classname =
483 sv_isobject(ST(0)) /* get the class if called as an object method */
484 ? HvNAME(SvSTASH(SvRV(ST(0))))
485 : (char *)SvPV_nolen(ST(0));
487 if ( items == 1 || vs == &PL_sv_undef ) { /* no param or explicit undef */
488 /* create empty object */
492 else if ( items == 3 ) {
494 Perl_sv_setpvf(aTHX_ vs,"v%s",SvPV_nolen_const(ST(2)));
497 rv = new_version(vs);
498 if ( strcmp(classname,"version") != 0 ) /* inherited new() */
499 sv_bless(rv, gv_stashpv(classname,TRUE));
501 PUSHs(sv_2mortal(rv));
507 XS(XS_version_stringify)
512 Perl_croak(aTHX_ "Usage: version::stringify(lobj, ...)");
517 if (sv_derived_from(ST(0), "version")) {
521 Perl_croak(aTHX_ "lobj is not of type version");
523 PUSHs(sv_2mortal(vstringify(lobj)));
530 XS(XS_version_numify)
535 Perl_croak(aTHX_ "Usage: version::numify(lobj, ...)");
540 if (sv_derived_from(ST(0), "version")) {
544 Perl_croak(aTHX_ "lobj is not of type version");
546 PUSHs(sv_2mortal(vnumify(lobj)));
553 XS(XS_version_normal)
558 Perl_croak(aTHX_ "Usage: version::normal(lobj, ...)");
563 if (sv_derived_from(ST(0), "version")) {
567 Perl_croak(aTHX_ "lobj is not of type version");
569 PUSHs(sv_2mortal(vnormal(lobj)));
581 Perl_croak(aTHX_ "Usage: version::vcmp(lobj, ...)");
586 if (sv_derived_from(ST(0), "version")) {
590 Perl_croak(aTHX_ "lobj is not of type version");
596 const IV swap = (IV)SvIV(ST(2));
598 if ( ! sv_derived_from(robj, "version") )
600 robj = new_version(robj);
606 rs = newSViv(vcmp(rvs,lobj));
610 rs = newSViv(vcmp(lobj,rvs));
613 PUSHs(sv_2mortal(rs));
621 XS(XS_version_boolean)
626 Perl_croak(aTHX_ "Usage: version::boolean(lobj, ...)");
628 if (sv_derived_from(ST(0), "version")) {
629 SV * const lobj = SvRV(ST(0));
630 SV * const rs = newSViv( vcmp(lobj,new_version(newSVpvs("0"))) );
631 PUSHs(sv_2mortal(rs));
636 Perl_croak(aTHX_ "lobj is not of type version");
644 Perl_croak(aTHX_ "Usage: version::noop(lobj, ...)");
645 if (sv_derived_from(ST(0), "version"))
646 Perl_croak(aTHX_ "operation not supported with version object");
648 Perl_croak(aTHX_ "lobj is not of type version");
649 #ifndef HASATTRIBUTE_NORETURN
654 XS(XS_version_is_alpha)
659 Perl_croak(aTHX_ "Usage: version::is_alpha(lobj)");
661 if (sv_derived_from(ST(0), "version")) {
662 SV * const lobj = ST(0);
663 if ( hv_exists((HV*)SvRV(lobj), "alpha", 5 ) )
671 Perl_croak(aTHX_ "lobj is not of type version");
679 Perl_croak(aTHX_ "Usage: version::qv(ver)");
683 if ( !SvVOK(ver) ) { /* only need to do with if not already v-string */
684 SV * const vs = sv_newmortal();
686 if ( SvNOK(ver) ) /* may get too much accuracy */
689 const STRLEN len = my_snprintf(tbuf, sizeof(tbuf), "%.9"NVgf, SvNVX(ver));
690 version = savepvn(tbuf, len);
694 version = savesvpv(ver);
696 (void)scan_version(version,vs,TRUE);
703 PUSHs(sv_2mortal(new_version(ver)));
716 Perl_croak(aTHX_ "Usage: utf8::is_utf8(sv)");
718 const SV * const sv = ST(0);
732 Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
734 SV * const sv = ST(0);
736 const char * const s = SvPV_const(sv,len);
737 if (!SvUTF8(sv) || is_utf8_string((const U8*)s,len))
750 Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
751 sv_utf8_encode(ST(0));
760 Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
762 SV * const sv = ST(0);
763 const bool RETVAL = sv_utf8_decode(sv);
764 ST(0) = boolSV(RETVAL);
775 Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
777 SV * const sv = ST(0);
781 RETVAL = sv_utf8_upgrade(sv);
782 XSprePUSH; PUSHi((IV)RETVAL);
787 XS(XS_utf8_downgrade)
791 if (items < 1 || items > 2)
792 Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
794 SV * const sv = ST(0);
795 const bool failok = (items < 2) ? 0 : (int)SvIV(ST(1));
796 const bool RETVAL = sv_utf8_downgrade(sv, failok);
798 ST(0) = boolSV(RETVAL);
804 XS(XS_utf8_native_to_unicode)
808 const UV uv = SvUV(ST(0));
811 Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
813 ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
817 XS(XS_utf8_unicode_to_native)
821 const UV uv = SvUV(ST(0));
824 Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
826 ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
830 XS(XS_Internals_SvREADONLY) /* This is dangerous stuff. */
834 SV * const sv = SvRV(ST(0));
842 else if (items == 2) {
848 /* I hope you really know what you are doing. */
853 XSRETURN_UNDEF; /* Can't happen. */
856 XS(XS_Internals_SvREFCNT) /* This is dangerous stuff. */
860 SV * const sv = SvRV(ST(0));
863 XSRETURN_IV(SvREFCNT(sv) - 1); /* Minus the ref created for us. */
864 else if (items == 2) {
865 /* I hope you really know what you are doing. */
866 SvREFCNT(sv) = SvIV(ST(1));
867 XSRETURN_IV(SvREFCNT(sv));
869 XSRETURN_UNDEF; /* Can't happen. */
872 XS(XS_Internals_hv_clear_placehold)
878 Perl_croak(aTHX_ "Usage: UNIVERSAL::hv_clear_placeholders(hv)");
880 HV * const hv = (HV *) SvRV(ST(0));
881 hv_clear_placeholders(hv);
886 XS(XS_Regexp_DESTROY)
892 XS(XS_PerlIO_get_layers)
896 if (items < 1 || items % 2 == 0)
897 Perl_croak(aTHX_ "Usage: PerlIO_get_layers(filehandle[,args])");
904 bool details = FALSE;
908 for (svp = MARK + 2; svp <= SP; svp += 2) {
909 SV * const * const varp = svp;
910 SV * const * const valp = svp + 1;
912 const char * const key = SvPV_const(*varp, klen);
916 if (klen == 5 && memEQ(key, "input", 5)) {
917 input = SvTRUE(*valp);
922 if (klen == 6 && memEQ(key, "output", 6)) {
923 input = !SvTRUE(*valp);
928 if (klen == 7 && memEQ(key, "details", 7)) {
929 details = SvTRUE(*valp);
936 "get_layers: unknown argument '%s'",
948 if (SvROK(sv) && isGV(SvRV(sv)))
951 gv = gv_fetchsv(sv, 0, SVt_PVIO);
954 if (gv && (io = GvIO(gv))) {
956 AV* const av = PerlIO_get_layers(aTHX_ input ?
957 IoIFP(io) : IoOFP(io));
959 const I32 last = av_len(av);
962 for (i = last; i >= 0; i -= 3) {
963 SV * const * const namsvp = av_fetch(av, i - 2, FALSE);
964 SV * const * const argsvp = av_fetch(av, i - 1, FALSE);
965 SV * const * const flgsvp = av_fetch(av, i, FALSE);
967 const bool namok = namsvp && *namsvp && SvPOK(*namsvp);
968 const bool argok = argsvp && *argsvp && SvPOK(*argsvp);
969 const bool flgok = flgsvp && *flgsvp && SvIOK(*flgsvp);
973 ? newSVpvn(SvPVX_const(*namsvp), SvCUR(*namsvp))
976 ? newSVpvn(SvPVX_const(*argsvp), SvCUR(*argsvp))
979 XPUSHi(SvIVX(*flgsvp));
981 XPUSHs(&PL_sv_undef);
986 XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf"(%"SVf")",
990 XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf,
993 XPUSHs(&PL_sv_undef);
996 const IV flags = SvIVX(*flgsvp);
998 if (flags & PERLIO_F_UTF8) {
999 XPUSHs(newSVpvs("utf8"));
1016 XS(XS_Internals_hash_seed)
1019 /* Using dXSARGS would also have dITEM and dSP,
1020 * which define 2 unused local variables. */
1022 PERL_UNUSED_ARG(cv);
1023 PERL_UNUSED_VAR(mark);
1024 XSRETURN_UV(PERL_HASH_SEED);
1027 XS(XS_Internals_rehash_seed)
1030 /* Using dXSARGS would also have dITEM and dSP,
1031 * which define 2 unused local variables. */
1033 PERL_UNUSED_ARG(cv);
1034 PERL_UNUSED_VAR(mark);
1035 XSRETURN_UV(PL_rehash_seed);
1038 XS(XS_Internals_HvREHASH) /* Subject to change */
1043 const HV * const hv = (HV *) SvRV(ST(0));
1044 if (items == 1 && SvTYPE(hv) == SVt_PVHV) {
1051 Perl_croak(aTHX_ "Internals::HvREHASH $hashref");
1054 XS(XS_Internals_inc_sub_generation)
1057 /* Using dXSARGS would also have dITEM and dSP,
1058 * which define 2 unused local variables. */
1060 PERL_UNUSED_ARG(cv);
1061 PERL_UNUSED_VAR(mark);
1062 ++PL_sub_generation;
1068 * c-indentation-style: bsd
1070 * indent-tabs-mode: t
1073 * ex: set ts=8 sts=4 sw=4 noet: