6 /* Most of this code is backported from the bleadperl patch's
7 mro.c, and then modified to work with Class::C3's
11 /* This is %next::METHOD_CACHE */
15 __mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level)
21 const char* stashname;
27 stashname = HvNAME(stash);
28 stashname_len = strlen(stashname);
31 "Can't linearize anonymous symbol table");
34 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
38 cache = (HV*)sv_2mortal((SV*)newHV());
41 SV** cache_entry = hv_fetch(cache, stashname, stashname_len, 0);
43 return (AV*)SvREFCNT_inc(*cache_entry);
46 /* not in cache, make a new one */
48 retval = (AV*)sv_2mortal((SV*)newAV());
49 av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */
51 gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE);
52 isa = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : NULL;
54 if(isa && AvFILLp(isa) >= 0) {
57 HV* tails = (HV*)sv_2mortal((SV*)newHV());
58 AV* seqs = (AV*)sv_2mortal((SV*)newAV());
59 I32 items = AvFILLp(isa) + 1;
60 SV** isa_ptr = AvARRAY(isa);
63 SV* isa_item = *isa_ptr++;
64 HV* isa_item_stash = gv_stashsv(isa_item, 0);
67 av_push(isa_lin, newSVsv(isa_item));
70 isa_lin = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ isa_item_stash, cache, level + 1)); /* recursion */
72 av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin)));
74 av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa)));
76 seqs_ptr = AvARRAY(seqs);
77 seqs_items = AvFILLp(seqs) + 1;
79 AV* seq = (AV*)*seqs_ptr++;
80 I32 seq_items = AvFILLp(seq);
82 SV** seq_ptr = AvARRAY(seq) + 1;
84 SV* seqitem = *seq_ptr++;
85 HE* he = hv_fetch_ent(tails, seqitem, 0, 0);
87 hv_store_ent(tails, seqitem, newSViv(1), 0);
104 SV** avptr = AvARRAY(seqs);
105 items = AvFILLp(seqs)+1;
109 if(AvFILLp(seq) < 0) continue;
110 svp = av_fetch(seq, 0, 0);
114 if((tail_entry = hv_fetch_ent(tails, cand, 0, 0))
115 && (val = HeVAL(tail_entry))
118 winner = newSVsv(cand);
119 av_push(retval, winner);
121 if(!sv_cmp(seqhead, winner)) {
122 sv_2mortal(av_shift(seq));
123 if(AvFILLp(seq) < 0) continue;
124 svp = av_fetch(seq, 0, 0);
126 tail_entry = hv_fetch_ent(tails, seqhead, 0, 0);
127 val = HeVAL(tail_entry);
133 Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': "
134 "merging failed on parent '%s'", stashname, SvPV_nolen(cand));
138 SvREADONLY_on(retval);
139 SvREFCNT_inc(retval); /* for cache storage */
140 SvREFCNT_inc(retval); /* for return */
141 hv_store(cache, stashname, stashname_len, (SV*)retval, 0);
146 __dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) {
148 for (i = startingblock; i >= 0; i--) {
149 if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i;
155 __nextcan(pTHX_ SV* self, I32 throw_nomethod)
158 register const PERL_CONTEXT *ccstack = cxstack;
159 const PERL_SI *top_si = PL_curstackinfo;
163 const char *fq_subname;
165 STRLEN fq_subname_len;
166 STRLEN stashname_len;
174 GV* candidate = NULL;
181 if(sv_isobject(self))
182 selfstash = SvSTASH(SvRV(self));
184 selfstash = gv_stashsv(self, 0);
188 hvname = HvNAME(selfstash);
190 croak("Can't use anonymous symbol table for method lookup");
192 cxix = __dopoptosub_at(cxstack, cxstack_ix);
194 /* This block finds the contextually-enclosing fully-qualified subname,
195 much like looking at (caller($i))[3] until you find a real sub that
198 /* we may be in a higher stacklevel, so dig down deeper */
200 if(top_si->si_type == PERLSI_MAIN)
201 croak("next::method/next::can/maybe::next::method must be used in method context");
202 top_si = top_si->si_prev;
203 ccstack = top_si->si_cxstack;
204 cxix = __dopoptosub_at(ccstack, top_si->si_cxix);
207 if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB
208 || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) {
209 cxix = __dopoptosub_at(ccstack, cxix - 1);
214 const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1);
215 if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) {
216 if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) {
223 cvgv = CvGV(ccstack[cxix].blk_sub.cv);
226 cxix = __dopoptosub_at(ccstack, cxix - 1);
230 /* we found a real sub here */
231 sv = sv_2mortal(newSV(0));
233 gv_efullname3(sv, cvgv, NULL);
235 fq_subname = SvPVX(sv);
236 fq_subname_len = SvCUR(sv);
238 subname = strrchr(fq_subname, ':');
240 croak("next::method/next::can/maybe::next::method cannot find enclosing method");
243 subname_len = fq_subname_len - (subname - fq_subname);
244 if(subname_len == 8 && strEQ(subname, "__ANON__")) {
245 cxix = __dopoptosub_at(ccstack, cxix - 1);
251 /* If we made it to here, we found our context */
253 /* cachekey = "objpkg|context::method::name" */
254 cachekey = sv_2mortal(newSVpv(hvname, 0));
255 sv_catpvn(cachekey, "|", 1);
256 sv_catsv(cachekey, sv);
258 if((cache_entry = hv_fetch_ent(nmcache, cachekey, 0, 0))) {
259 SV* val = HeVAL(cache_entry);
260 if(val == &PL_sv_undef) {
262 croak("No next::method '%s' found for %s", subname, hvname);
265 return SvREFCNT_inc(val);
268 /* beyond here is just for cache misses, so perf isn't as critical */
270 stashname_len = subname - fq_subname - 2;
271 stashname = sv_2mortal(newSVpvn(fq_subname, stashname_len));
273 linear_av = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ selfstash, NULL, 0));
275 linear_svp = AvARRAY(linear_av);
276 items = AvFILLp(linear_av) + 1;
279 linear_sv = *linear_svp++;
281 if(sv_eq(linear_sv, stashname))
286 SV* sub_sv = sv_2mortal(newSVpv(subname, subname_len));
287 HV* cc3_mro = get_hv("Class::C3::MRO", 0);
290 linear_sv = *linear_svp++;
294 HE* he_cc3_mro_class = hv_fetch_ent(cc3_mro, linear_sv, 0, 0);
295 if(he_cc3_mro_class) {
296 HV* cc3_mro_class = (HV*)SvRV(HeVAL(he_cc3_mro_class));
297 SV** svp_cc3_mro_class_methods = hv_fetch(cc3_mro_class, "methods", 7, 0);
298 if(svp_cc3_mro_class_methods) {
299 HV* cc3_mro_class_methods = (HV*)SvRV(*svp_cc3_mro_class_methods);
300 if(hv_exists_ent(cc3_mro_class_methods, sub_sv, 0))
306 cstash = gv_stashsv(linear_sv, FALSE);
309 if (ckWARN(WARN_MISC))
310 Perl_warner(aTHX_ packWARN(WARN_MISC), "Can't locate package %"SVf" for @%s::ISA",
311 (void*)linear_sv, hvname);
317 gvp = (GV**)hv_fetch(cstash, subname, subname_len, 0);
323 if (SvTYPE(candidate) != SVt_PVGV)
324 gv_init(candidate, cstash, subname, subname_len, TRUE);
325 if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
326 SvREFCNT_inc((SV*)cand_cv);
327 hv_store_ent(nmcache, newSVsv(cachekey), (SV*)cand_cv, 0);
333 hv_store_ent(nmcache, newSVsv(cachekey), &PL_sv_undef, 0);
335 croak("No next::method '%s' found for %s", subname, hvname);
339 XS(XS_Class_C3_XS_calculateMRO);
340 XS(XS_Class_C3_XS_calculateMRO)
356 if(items < 1 || items > 2)
357 croak("Usage: calculateMRO(classname[, cache])");
360 if(items == 2) cache = (HV*)SvRV(ST(1));
362 class_stash = gv_stashsv(classname, 0);
363 if(!class_stash) croak("No such class: '%s'!", SvPV_nolen(classname));
365 res = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ class_stash, cache, 0));
367 res_items = ret_items = AvFILLp(res) + 1;
368 res_ptr = AvARRAY(res);
373 SV* res_item = *res_ptr++;
392 SV* methcv = __nextcan(aTHX_ self, 0);
394 PERL_UNUSED_VAR(items);
396 if(methcv == &PL_sv_undef) {
397 ST(0) = &PL_sv_undef;
400 ST(0) = sv_2mortal(newRV_inc(methcv));
412 SV* methcv = __nextcan(aTHX_ self, 1);
415 call_sv(methcv, GIMME_V);
418 XS(XS_maybe_next_method);
419 XS(XS_maybe_next_method)
424 SV* methcv = __nextcan(aTHX_ self, 0);
426 if(methcv == &PL_sv_undef) {
427 ST(0) = &PL_sv_undef;
432 call_sv(methcv, GIMME_V);
435 MODULE = Class::C3::XS PACKAGE = Class::C3::XS
438 nmcache = get_hv("next::METHOD_CACHE", 1);
439 newXS("Class::C3::XS::calculateMRO", XS_Class_C3_XS_calculateMRO, __FILE__);
440 newXS("next::can", XS_next_can, __FILE__);
441 newXS("next::method", XS_next_method, __FILE__);
442 newXS("maybe::next::method", XS_maybe_next_method, __FILE__);