2 #define PERL_IN_UNIVERSAL_C
6 * Contributed by Graham Barr <Graham.Barr@tiuk.ti.com>
7 * The main guts of traverse_isa was actually copied from gv_fetchmeth
11 S_isa_lookup(pTHX_ HV *stash, const char *name, int len, int level)
21 if(strEQ(HvNAME(stash), name))
25 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", HvNAME(stash));
27 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
29 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (hv = GvHV(gv))) {
31 SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
32 if (svp && (sv = *svp) != (SV*)&PL_sv_undef)
36 gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
38 if (gvp && (gv = *gvp) != (GV*)&PL_sv_undef && (av = GvAV(gv))) {
40 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
44 if (SvTYPE(gv) != SVt_PVGV)
45 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
50 SV** svp = AvARRAY(av);
51 /* NOTE: No support for tied ISA */
52 I32 items = AvFILLp(av) + 1;
55 HV* basestash = gv_stashsv(sv, FALSE);
58 if (ckWARN(WARN_MISC))
59 Perl_warner(aTHX_ WARN_SYNTAX,
60 "Can't locate package %s for @%s::ISA",
61 SvPVX(sv), HvNAME(stash));
64 if(&PL_sv_yes == isa_lookup(basestash, name, len, level + 1)) {
65 (void)hv_store(hv,name,len,&PL_sv_yes,0);
69 (void)hv_store(hv,name,len,&PL_sv_no,0);
73 return boolSV(strEQ(name, "UNIVERSAL"));
77 =for apidoc sv_derived_from
79 Returns a boolean indicating whether the SV is derived from the specified
80 class. This is the function that implements C<UNIVERSAL::isa>. It works
81 for class names as well as for objects.
87 Perl_sv_derived_from(pTHX_ SV *sv, const char *name)
100 type = sv_reftype(sv,0);
105 stash = gv_stashsv(sv, FALSE);
108 return (type && strEQ(type,name)) ||
109 (stash && isa_lookup(stash, name, strlen(name), 0) == &PL_sv_yes)
114 void XS_UNIVERSAL_isa(pTHXo_ CV *cv);
115 void XS_UNIVERSAL_can(pTHXo_ CV *cv);
116 void XS_UNIVERSAL_VERSION(pTHXo_ CV *cv);
119 Perl_boot_core_UNIVERSAL(pTHX)
121 char *file = __FILE__;
123 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
124 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
125 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);
138 Perl_croak(aTHX_ "Usage: UNIVERSAL::isa(reference, kind)");
145 if (!SvOK(sv) || !(SvROK(sv) || SvCUR(sv)))
148 name = (char *)SvPV(ST(1),n_a);
150 ST(0) = boolSV(sv_derived_from(sv, name));
164 Perl_croak(aTHX_ "Usage: UNIVERSAL::can(object-ref, method)");
171 if (!SvOK(sv) || !(SvROK(sv) || SvCUR(sv)))
174 name = (char *)SvPV(ST(1),n_a);
183 pkg = gv_stashsv(sv, FALSE);
187 GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
189 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
196 XS(XS_UNIVERSAL_VERSION)
206 sv = (SV*)SvRV(ST(0));
208 Perl_croak(aTHX_ "Cannot find version of an unblessed reference");
212 pkg = gv_stashsv(ST(0), FALSE);
215 gvp = pkg ? (GV**)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV**);
217 if (gvp && isGV(gv = *gvp) && SvOK(sv = GvSV(gv))) {
218 SV *nsv = sv_newmortal();
224 sv = (SV*)&PL_sv_undef;
233 Perl_croak(aTHX_ "%s does not define $%s::VERSION--version check failed",
234 HvNAME(pkg), HvNAME(pkg));
236 if (!SvNIOK(sv) && SvPOK(sv)) {
237 char *str = SvPVx(sv,len);
240 /* XXX could DWIM "1.2.3" here */
241 if (!isDIGIT(str[len]) && str[len] != '.' && str[len] != '_')
245 if (SvNIOKp(req) && SvPOK(req)) {
246 /* they said C<use Foo v1.2.3> and $Foo::VERSION
247 * doesn't look like a float: do string compare */
248 if (sv_cmp(req,sv) == 1) {
249 Perl_croak(aTHX_ "%s version v%vd required--"
250 "this is only version v%vd",
251 HvNAME(pkg), req, sv);
255 /* they said C<use Foo 1.002_003> and $Foo::VERSION
256 * doesn't look like a float: force numeric compare */
257 (void)SvUPGRADE(sv, SVt_PVNV);
258 SvNVX(sv) = str_to_version(sv);
263 /* if we get here, we're looking for a numeric comparison,
264 * so force the required version into a float, even if they
265 * said C<use Foo v1.2.3> */
266 if (SvNIOKp(req) && SvPOK(req)) {
268 req = sv_newmortal();
272 if (SvNV(req) > SvNV(sv))
273 Perl_croak(aTHX_ "%s version %s required--this is only version %s",
274 HvNAME(pkg), SvPV(req,len), SvPV(sv,len));