3 * Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
4 * 2005, 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,
45 /* A stash/class can go by many names (ie. User == main::User), so
46 we compare the stash itself just in case */
47 if (name_stash && (stash == name_stash))
50 hvname = HvNAME_get(stash);
52 if (strEQ(hvname, name))
55 if (strEQ(name, "UNIVERSAL"))
59 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
62 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
64 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (subgen = GvSV(gv))
67 if (SvIV(subgen) == (IV)PL_sub_generation) {
69 SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
70 if (svp && (sv = *svp) != (SV*)&PL_sv_undef) {
71 DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
77 DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
80 sv_setiv(subgen, PL_sub_generation);
84 gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
86 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
88 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
92 if (SvTYPE(gv) != SVt_PVGV)
93 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
98 subgen = newSViv(PL_sub_generation);
103 SV** svp = AvARRAY(av);
104 /* NOTE: No support for tied ISA */
105 I32 items = AvFILLp(av) + 1;
108 HV* basestash = gv_stashsv(sv, FALSE);
110 if (ckWARN(WARN_MISC))
111 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
112 "Can't locate package %"SVf" for @%s::ISA",
116 if (&PL_sv_yes == isa_lookup(basestash, name, name_stash,
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
134 class. This is the function that implements C<UNIVERSAL::isa>. It works
135 for class names as well as for objects.
141 Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
143 const char *type = Nullch;
152 type = sv_reftype(sv,0);
157 stash = gv_stashsv(sv, FALSE);
160 name_stash = gv_stashpv(name, FALSE);
162 return (type && strEQ(type,name)) ||
163 (stash && isa_lookup(stash, name, name_stash, strlen(name), 0)
171 PERL_XS_EXPORT_C void XS_UNIVERSAL_isa(pTHX_ CV *cv);
172 PERL_XS_EXPORT_C void XS_UNIVERSAL_can(pTHX_ CV *cv);
173 PERL_XS_EXPORT_C void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
175 XS(XS_version_stringify);
176 XS(XS_version_numify);
178 XS(XS_version_boolean);
179 #ifdef HASATTRIBUTE_NORETURN
180 XS(XS_version_noop) __attribute__noreturn__;
184 XS(XS_version_is_alpha);
191 XS(XS_utf8_downgrade);
192 XS(XS_utf8_unicode_to_native);
193 XS(XS_utf8_native_to_unicode);
194 XS(XS_Internals_SvREADONLY);
195 XS(XS_Internals_SvREFCNT);
196 XS(XS_Internals_hv_clear_placehold);
197 XS(XS_PerlIO_get_layers);
198 XS(XS_Regexp_DESTROY);
199 XS(XS_Internals_hash_seed);
200 XS(XS_Internals_rehash_seed);
201 XS(XS_Internals_HvREHASH);
204 Perl_boot_core_UNIVERSAL(pTHX)
206 const char file[] = __FILE__;
208 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
209 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
210 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
212 /* register the overloading (type 'A') magic */
213 PL_amagic_generation++;
214 /* Make it findable via fetchmethod */
215 newXS("version::()", XS_version_noop, file);
216 newXS("version::new", XS_version_new, file);
217 newXS("version::(\"\"", XS_version_stringify, file);
218 newXS("version::stringify", XS_version_stringify, file);
219 newXS("version::(0+", XS_version_numify, file);
220 newXS("version::numify", XS_version_numify, file);
221 newXS("version::(cmp", XS_version_vcmp, file);
222 newXS("version::(<=>", XS_version_vcmp, file);
223 newXS("version::vcmp", XS_version_vcmp, file);
224 newXS("version::(bool", XS_version_boolean, file);
225 newXS("version::boolean", XS_version_boolean, file);
226 newXS("version::(nomethod", XS_version_noop, file);
227 newXS("version::noop", XS_version_noop, file);
228 newXS("version::is_alpha", XS_version_is_alpha, file);
229 newXS("version::qv", XS_version_qv, file);
231 newXS("utf8::is_utf8", XS_utf8_is_utf8, file);
232 newXS("utf8::valid", XS_utf8_valid, file);
233 newXS("utf8::encode", XS_utf8_encode, file);
234 newXS("utf8::decode", XS_utf8_decode, file);
235 newXS("utf8::upgrade", XS_utf8_upgrade, file);
236 newXS("utf8::downgrade", XS_utf8_downgrade, file);
237 newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
238 newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
239 newXSproto("Internals::SvREADONLY",XS_Internals_SvREADONLY, file, "\\[$%@];$");
240 newXSproto("Internals::SvREFCNT",XS_Internals_SvREFCNT, file, "\\[$%@];$");
241 newXSproto("Internals::hv_clear_placeholders",
242 XS_Internals_hv_clear_placehold, file, "\\%");
243 newXSproto("PerlIO::get_layers",
244 XS_PerlIO_get_layers, file, "*;@");
245 newXS("Regexp::DESTROY", XS_Regexp_DESTROY, file);
246 newXSproto("Internals::hash_seed",XS_Internals_hash_seed, file, "");
247 newXSproto("Internals::rehash_seed",XS_Internals_rehash_seed, file, "");
248 newXSproto("Internals::HvREHASH", XS_Internals_HvREHASH, file, "\\%");
260 Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
267 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
268 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
271 name = (const char *)SvPV(ST(1),n_a);
273 ST(0) = boolSV(sv_derived_from(sv, name));
287 Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
294 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))
295 || (SvGMAGICAL(sv) && SvPOKp(sv) && SvCUR(sv))))
298 name = (const char *)SvPV(ST(1),n_a);
307 pkg = gv_stashsv(sv, FALSE);
311 GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
313 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
320 XS(XS_UNIVERSAL_VERSION)
330 sv = (SV*)SvRV(ST(0));
332 Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
336 pkg = gv_stashsv(ST(0), FALSE);
339 gvp = pkg ? (GV**)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV**);
341 if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
342 SV *nsv = sv_newmortal();
345 if ( !sv_derived_from(sv, "version"))
350 sv = (SV*)&PL_sv_undef;
359 const char *name = HvNAME_get(pkg);
361 "%s does not define $%s::VERSION--version check failed",
366 "%s defines neither package nor VERSION--version check failed",
371 if ( !sv_derived_from(req, "version")) {
372 /* req may very well be R/O, so create a new object */
373 SV *nsv = sv_newmortal();
379 if ( vcmp( req, sv ) > 0 )
380 Perl_croak(aTHX_ "%s version %"SVf" (%"SVf") required--"
381 "this is only version %"SVf" (%"SVf")", HvNAME_get(pkg),
382 vnumify(req),vnormal(req),vnumify(sv),vnormal(sv));
385 if ( SvOK(sv) && sv_derived_from(sv, "version") ) {
398 Perl_croak(aTHX_ "Usage: version::new(class, version)");
401 const char *classname = SvPV_nolen(ST(0));
407 Perl_sv_setpvf(aTHX_ vs,"v%s",SvPV_nolen(ST(2)));
410 rv = new_version(vs);
411 if ( strcmp(classname,"version") != 0 ) /* inherited new() */
412 sv_bless(rv, gv_stashpv(classname,TRUE));
414 PUSHs(sv_2mortal(rv));
420 XS(XS_version_stringify)
424 Perl_croak(aTHX_ "Usage: version::stringify(lobj, ...)");
429 if (sv_derived_from(ST(0), "version")) {
430 SV *tmp = SvRV(ST(0));
434 Perl_croak(aTHX_ "lobj is not of type version");
436 PUSHs(sv_2mortal(vstringify(lobj)));
443 XS(XS_version_numify)
447 Perl_croak(aTHX_ "Usage: version::numify(lobj, ...)");
452 if (sv_derived_from(ST(0), "version")) {
453 SV *tmp = SvRV(ST(0));
457 Perl_croak(aTHX_ "lobj is not of type version");
459 PUSHs(sv_2mortal(vnumify(lobj)));
470 Perl_croak(aTHX_ "Usage: version::vcmp(lobj, ...)");
475 if (sv_derived_from(ST(0), "version")) {
476 SV *tmp = SvRV(ST(0));
480 Perl_croak(aTHX_ "lobj is not of type version");
486 IV swap = (IV)SvIV(ST(2));
488 if ( ! sv_derived_from(robj, "version") )
490 robj = new_version(robj);
496 rs = newSViv(vcmp(rvs,lobj));
500 rs = newSViv(vcmp(lobj,rvs));
503 PUSHs(sv_2mortal(rs));
511 XS(XS_version_boolean)
515 Perl_croak(aTHX_ "Usage: version::boolean(lobj, ...)");
520 if (sv_derived_from(ST(0), "version")) {
521 /* XXX If tmp serves a purpose, explain it. */
522 SV *tmp = SvRV(ST(0));
526 Perl_croak(aTHX_ "lobj is not of type version");
530 rs = newSViv( vcmp(lobj,new_version(newSVpvn("0",1))) );
531 PUSHs(sv_2mortal(rs));
543 Perl_croak(aTHX_ "Usage: version::noop(lobj, ...)");
544 if (sv_derived_from(ST(0), "version"))
545 Perl_croak(aTHX_ "operation not supported with version object");
547 Perl_croak(aTHX_ "lobj is not of type version");
548 #ifndef HASATTRIBUTE_NORETURN
553 XS(XS_version_is_alpha)
557 Perl_croak(aTHX_ "Usage: version::is_alpha(lobj)");
562 if (sv_derived_from(ST(0), "version")) {
563 /* XXX If tmp serves a purpose, explain it. */
564 SV *tmp = SvRV(ST(0));
568 Perl_croak(aTHX_ "lobj is not of type version");
570 const I32 len = av_len((AV *)lobj);
571 const I32 digit = SvIVX(*av_fetch((AV *)lobj, len, 0));
586 Perl_croak(aTHX_ "Usage: version::qv(ver)");
590 if ( !SvVOK(ver) ) /* only need to do with if not already v-string */
592 SV *vs = sv_newmortal();
594 if ( SvNOK(ver) ) /* may get too much accuracy */
597 sprintf(tbuf,"%.9"NVgf, SvNVX(ver));
598 version = savepv(tbuf);
602 version = savesvpv(ver);
604 (void)scan_version(version,vs,TRUE);
611 PUSHs(sv_2mortal(new_version(ver)));
623 Perl_croak(aTHX_ "Usage: utf8::is_utf8(sv)");
625 const SV *sv = ST(0);
640 Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
645 const char *s = SvPV(sv,len);
646 if (!SvUTF8(sv) || is_utf8_string((const U8*)s,len))
659 Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
672 Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
675 const bool RETVAL = sv_utf8_decode(sv);
676 ST(0) = boolSV(RETVAL);
686 Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
692 RETVAL = sv_utf8_upgrade(sv);
693 XSprePUSH; PUSHi((IV)RETVAL);
698 XS(XS_utf8_downgrade)
701 if (items < 1 || items > 2)
702 Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
705 const bool failok = (items < 2) ? 0 : (int)SvIV(ST(1));
706 const bool RETVAL = sv_utf8_downgrade(sv, failok);
708 ST(0) = boolSV(RETVAL);
714 XS(XS_utf8_native_to_unicode)
717 const UV uv = SvUV(ST(0));
720 Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
722 ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
726 XS(XS_utf8_unicode_to_native)
729 const UV uv = SvUV(ST(0));
732 Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
734 ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
738 XS(XS_Internals_SvREADONLY) /* This is dangerous stuff. */
741 SV *sv = SvRV(ST(0));
749 else if (items == 2) {
755 /* I hope you really know what you are doing. */
760 XSRETURN_UNDEF; /* Can't happen. */
763 XS(XS_Internals_SvREFCNT) /* This is dangerous stuff. */
766 SV *sv = SvRV(ST(0));
769 XSRETURN_IV(SvREFCNT(sv) - 1); /* Minus the ref created for us. */
770 else if (items == 2) {
771 /* I hope you really know what you are doing. */
772 SvREFCNT(sv) = SvIV(ST(1));
773 XSRETURN_IV(SvREFCNT(sv));
775 XSRETURN_UNDEF; /* Can't happen. */
778 XS(XS_Internals_hv_clear_placehold)
781 HV *hv = (HV *) SvRV(ST(0));
784 Perl_croak(aTHX_ "Usage: UNIVERSAL::hv_clear_placeholders(hv)");
785 hv_clear_placeholders(hv);
789 XS(XS_Regexp_DESTROY)
793 XS(XS_PerlIO_get_layers)
796 if (items < 1 || items % 2 == 0)
797 Perl_croak(aTHX_ "Usage: PerlIO_get_layers(filehandle[,args])");
804 bool details = FALSE;
809 for (svp = MARK + 2; svp <= SP; svp += 2) {
813 const char *key = SvPV(*varp, klen);
817 if (klen == 5 && memEQ(key, "input", 5)) {
818 input = SvTRUE(*valp);
823 if (klen == 6 && memEQ(key, "output", 6)) {
824 input = !SvTRUE(*valp);
829 if (klen == 7 && memEQ(key, "details", 7)) {
830 details = SvTRUE(*valp);
837 "get_layers: unknown argument '%s'",
849 if (SvROK(sv) && isGV(SvRV(sv)))
852 gv = gv_fetchsv(sv, FALSE, SVt_PVIO);
855 if (gv && (io = GvIO(gv))) {
857 AV* av = PerlIO_get_layers(aTHX_ input ?
858 IoIFP(io) : IoOFP(io));
860 I32 last = av_len(av);
863 for (i = last; i >= 0; i -= 3) {
867 bool namok, argok, flgok;
869 namsvp = av_fetch(av, i - 2, FALSE);
870 argsvp = av_fetch(av, i - 1, FALSE);
871 flgsvp = av_fetch(av, i, FALSE);
873 namok = namsvp && *namsvp && SvPOK(*namsvp);
874 argok = argsvp && *argsvp && SvPOK(*argsvp);
875 flgok = flgsvp && *flgsvp && SvIOK(*flgsvp);
879 newSVpv(SvPVX_const(*namsvp), 0) : &PL_sv_undef);
881 newSVpv(SvPVX_const(*argsvp), 0) : &PL_sv_undef);
883 XPUSHi(SvIVX(*flgsvp));
885 XPUSHs(&PL_sv_undef);
890 XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf"(%"SVf")",
893 XPUSHs(Perl_newSVpvf(aTHX_ "%"SVf, *namsvp));
895 XPUSHs(&PL_sv_undef);
898 IV flags = SvIVX(*flgsvp);
900 if (flags & PERLIO_F_UTF8) {
901 XPUSHs(newSVpvn("utf8", 4));
918 XS(XS_Internals_hash_seed)
920 /* Using dXSARGS would also have dITEM and dSP,
921 * which define 2 unused local variables. */
924 XSRETURN_UV(PERL_HASH_SEED);
927 XS(XS_Internals_rehash_seed)
929 /* Using dXSARGS would also have dITEM and dSP,
930 * which define 2 unused local variables. */
933 XSRETURN_UV(PL_rehash_seed);
936 XS(XS_Internals_HvREHASH) /* Subject to change */
940 const HV *hv = (HV *) SvRV(ST(0));
941 if (items == 1 && SvTYPE(hv) == SVt_PVHV) {
948 Perl_croak(aTHX_ "Internals::HvREHASH $hashref");
953 * c-indentation-style: bsd
955 * indent-tabs-mode: t
958 * ex: set ts=8 sts=4 sw=4 noet: