3 * Copyright (c) 1997-2002, Larry Wall
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
11 * "The roots of those mountains must be roots indeed; there must be
12 * great secrets buried there which have not been discovered since the
13 * beginning." --Gandalf, relating Gollum's story
17 #define PERL_IN_UNIVERSAL_C
21 * Contributed by Graham Barr <Graham.Barr@tiuk.ti.com>
22 * The main guts of traverse_isa was actually copied from gv_fetchmeth
26 S_isa_lookup(pTHX_ HV *stash, const char *name, HV* name_stash,
35 /* A stash/class can go by many names (ie. User == main::User), so
36 we compare the stash itself just in case */
37 if (name_stash && (stash == name_stash))
40 if (strEQ(HvNAME(stash), name))
44 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
47 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
49 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (subgen = GvSV(gv))
52 if (SvIV(subgen) == PL_sub_generation) {
54 SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
55 if (svp && (sv = *svp) != (SV*)&PL_sv_undef) {
56 DEBUG_o( Perl_deb(aTHX_ "Using cached ISA %s for package %s\n",
57 name, HvNAME(stash)) );
62 DEBUG_o( Perl_deb(aTHX_ "ISA Cache in package %s is stale\n",
65 sv_setiv(subgen, PL_sub_generation);
69 gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
71 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
73 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
77 if (SvTYPE(gv) != SVt_PVGV)
78 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
83 subgen = newSViv(PL_sub_generation);
88 SV** svp = AvARRAY(av);
89 /* NOTE: No support for tied ISA */
90 I32 items = AvFILLp(av) + 1;
93 HV* basestash = gv_stashsv(sv, FALSE);
95 if (ckWARN(WARN_MISC))
96 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
97 "Can't locate package %s for @%s::ISA",
98 SvPVX(sv), HvNAME(stash));
101 if (&PL_sv_yes == isa_lookup(basestash, name, name_stash,
103 (void)hv_store(hv,name,len,&PL_sv_yes,0);
107 (void)hv_store(hv,name,len,&PL_sv_no,0);
111 return boolSV(strEQ(name, "UNIVERSAL"));
115 =head1 SV Manipulation Functions
117 =for apidoc sv_derived_from
119 Returns a boolean indicating whether the SV is derived from the specified
120 class. This is the function that implements C<UNIVERSAL::isa>. It works
121 for class names as well as for objects.
127 Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
141 type = sv_reftype(sv,0);
146 stash = gv_stashsv(sv, FALSE);
149 name_stash = gv_stashpv(name, FALSE);
151 return (type && strEQ(type,name)) ||
152 (stash && isa_lookup(stash, name, name_stash, strlen(name), 0)
160 void XS_UNIVERSAL_isa(pTHX_ CV *cv);
161 void XS_UNIVERSAL_can(pTHX_ CV *cv);
162 void XS_UNIVERSAL_VERSION(pTHX_ CV *cv);
167 XS(XS_utf8_downgrade);
168 XS(XS_utf8_unicode_to_native);
169 XS(XS_utf8_native_to_unicode);
170 XS(XS_Internals_SvREADONLY);
171 XS(XS_Internals_SvREFCNT);
174 Perl_boot_core_UNIVERSAL(pTHX)
176 char *file = __FILE__;
178 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
179 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
180 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
181 newXS("utf8::valid", XS_utf8_valid, file);
182 newXS("utf8::encode", XS_utf8_encode, file);
183 newXS("utf8::decode", XS_utf8_decode, file);
184 newXS("utf8::upgrade", XS_utf8_upgrade, file);
185 newXS("utf8::downgrade", XS_utf8_downgrade, file);
186 newXS("utf8::native_to_unicode", XS_utf8_native_to_unicode, file);
187 newXS("utf8::unicode_to_native", XS_utf8_unicode_to_native, file);
188 newXSproto("Internals::SvREADONLY",XS_Internals_SvREADONLY, file, "\\[$%@];$");
189 newXSproto("Internals::SvREFCNT",XS_Internals_SvREFCNT, file, "\\[$%@];$");
201 Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
208 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))))
211 name = (char *)SvPV(ST(1),n_a);
213 ST(0) = boolSV(sv_derived_from(sv, name));
227 Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
234 if (!SvOK(sv) || !(SvROK(sv) || (SvPOK(sv) && SvCUR(sv))))
237 name = (char *)SvPV(ST(1),n_a);
246 pkg = gv_stashsv(sv, FALSE);
250 GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
252 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
259 XS(XS_UNIVERSAL_VERSION)
269 sv = (SV*)SvRV(ST(0));
271 Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
275 pkg = gv_stashsv(ST(0), FALSE);
278 gvp = pkg ? (GV**)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV**);
280 if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
281 SV *nsv = sv_newmortal();
287 sv = (SV*)&PL_sv_undef;
298 "%s does not define $%s::VERSION--version check failed",
299 HvNAME(pkg), HvNAME(pkg));
301 char *str = SvPVx(ST(0), len);
304 "%s defines neither package nor VERSION--version check failed", str);
307 if (!SvNIOK(sv) && SvPOK(sv)) {
308 char *str = SvPVx(sv,len);
311 /* XXX could DWIM "1.2.3" here */
312 if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
316 if (SvNOK(req) && SvPOK(req)) {
317 /* they said C<use Foo v1.2.3> and $Foo::VERSION
318 * doesn't look like a float: do string compare */
319 if (sv_cmp(req,sv) == 1) {
320 Perl_croak(aTHX_ "%s v%"VDf" required--"
321 "this is only v%"VDf,
322 HvNAME(pkg), req, sv);
326 /* they said C<use Foo 1.002_003> and $Foo::VERSION
327 * doesn't look like a float: force numeric compare */
328 (void)SvUPGRADE(sv, SVt_PVNV);
329 SvNVX(sv) = str_to_version(sv);
334 /* if we get here, we're looking for a numeric comparison,
335 * so force the required version into a float, even if they
336 * said C<use Foo v1.2.3> */
337 if (SvNOK(req) && SvPOK(req)) {
339 req = sv_newmortal();
343 if (SvNV(req) > SvNV(sv))
344 Perl_croak(aTHX_ "%s version %s required--this is only version %s",
345 HvNAME(pkg), SvPV_nolen(req), SvPV_nolen(sv));
358 Perl_croak(aTHX_ "Usage: utf8::valid(sv)");
363 char *s = SvPV(sv,len);
364 if (!SvUTF8(sv) || is_utf8_string((U8*)s,len))
377 Perl_croak(aTHX_ "Usage: utf8::encode(sv)");
390 Perl_croak(aTHX_ "Usage: utf8::decode(sv)");
395 RETVAL = sv_utf8_decode(sv);
396 ST(0) = boolSV(RETVAL);
406 Perl_croak(aTHX_ "Usage: utf8::upgrade(sv)");
412 RETVAL = sv_utf8_upgrade(sv);
413 XSprePUSH; PUSHi((IV)RETVAL);
418 XS(XS_utf8_downgrade)
421 if (items < 1 || items > 2)
422 Perl_croak(aTHX_ "Usage: utf8::downgrade(sv, failok=0)");
431 failok = (int)SvIV(ST(1));
434 RETVAL = sv_utf8_downgrade(sv, failok);
435 ST(0) = boolSV(RETVAL);
441 XS(XS_utf8_native_to_unicode)
447 Perl_croak(aTHX_ "Usage: utf8::native_to_unicode(sv)");
449 ST(0) = sv_2mortal(newSViv(NATIVE_TO_UNI(uv)));
453 XS(XS_utf8_unicode_to_native)
459 Perl_croak(aTHX_ "Usage: utf8::unicode_to_native(sv)");
461 ST(0) = sv_2mortal(newSViv(UNI_TO_NATIVE(uv)));
465 XS(XS_Internals_SvREADONLY) /* This is dangerous stuff. */
468 SV *sv = SvRV(ST(0));
475 else if (items == 2) {
481 /* I hope you really know what you are doing. */
486 XSRETURN_UNDEF; /* Can't happen. */
489 XS(XS_Internals_SvREFCNT) /* This is dangerous stuff. */
492 SV *sv = SvRV(ST(0));
494 XSRETURN_IV(SvREFCNT(sv) - 1); /* Minus the ref created for us. */
495 else if (items == 2) {
496 /* I hope you really know what you are doing. */
497 SvREFCNT(sv) = SvIV(ST(1));
498 XSRETURN_IV(SvREFCNT(sv));
500 XSRETURN_UNDEF; /* Can't happen. */