#include "perl.h"
#include "XSUB.h"
-/* TODO: put __calculate_mro here, from blead patch's mro_linear_c3 */
-/* TODO: put __nextcan / __poptosubat here, from blead patch */
+/* Most of this code is backported from bleadperl's
+ mro.c, and then modified to work with Class::C3's
+ internals.
+*/
-MODULE = Class::C3::XS PACKAGE = Class::C3::XS
+AV*
+__mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level)
+{
+ AV* retval;
+ GV** gvp;
+ GV* gv;
+ AV* isa;
+ const char* stashname;
+ STRLEN stashname_len;
-/* TODO: put calculateMRO here, uses __calculate_mro */
-
-MODULE = Class::C3::XS PACKAGE = next
+ assert(stash);
+ assert(HvAUX(stash));
-/* TODO: put next::method / next::can here */
+ stashname = HvNAME(stash);
+ stashname_len = strlen(stashname);
+ if (!stashname)
+ Perl_croak(aTHX_
+ "Can't linearize anonymous symbol table");
-MODULE = Class::C3::XS PACKAGE = maybe
+ if (level > 100)
+ Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
+ stashname);
-/* TODO: put maybe::next::method here */
+ if(!cache) {
+ cache = newHV();
+ }
+ else {
+ /* XXX return cached entry for stashname if available */
+ }
+
+ /* not in cache, make a new one */
+
+ retval = (AV*)sv_2mortal((SV*)newAV());
+ av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */
+
+ gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE);
+ isa = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : NULL;
+
+ if(isa && AvFILLp(isa) >= 0) {
+ SV** seqs_ptr;
+ I32 seqs_items;
+ HV* tails = (HV*)sv_2mortal((SV*)newHV());
+ AV* seqs = (AV*)sv_2mortal((SV*)newAV());
+ I32 items = AvFILLp(isa) + 1;
+ SV** isa_ptr = AvARRAY(isa);
+ while(items--) {
+ AV* isa_lin;
+ SV* isa_item = *isa_ptr++;
+ HV* isa_item_stash = gv_stashsv(isa_item, 0);
+ if(!isa_item_stash) {
+ isa_lin = newAV();
+ av_push(isa_lin, newSVsv(isa_item));
+ }
+ else {
+ isa_lin = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(isa_item_stash, cache, level + 1)); /* recursion */
+ }
+ av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin)));
+ }
+ av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa)));
+
+ seqs_ptr = AvARRAY(seqs);
+ seqs_items = AvFILLp(seqs) + 1;
+ while(seqs_items--) {
+ AV* seq = (AV*)*seqs_ptr++;
+ I32 seq_items = AvFILLp(seq);
+ if(seq_items > 0) {
+ SV** seq_ptr = AvARRAY(seq) + 1;
+ while(seq_items--) {
+ SV* seqitem = *seq_ptr++;
+ HE* he = hv_fetch_ent(tails, seqitem, 0, 0);
+ if(!he) {
+ hv_store_ent(tails, seqitem, newSViv(1), 0);
+ }
+ else {
+ SV* val = HeVAL(he);
+ sv_inc(val);
+ }
+ }
+ }
+ }
+
+ while(1) {
+ SV* seqhead = NULL;
+ SV* cand = NULL;
+ SV* winner = NULL;
+ SV* val;
+ HE* tail_entry;
+ AV* seq;
+ SV** avptr = AvARRAY(seqs);
+ items = AvFILLp(seqs)+1;
+ while(items--) {
+ SV** svp;
+ seq = (AV*)*avptr++;
+ if(AvFILLp(seq) < 0) continue;
+ svp = av_fetch(seq, 0, 0);
+ seqhead = *svp;
+ if(!winner) {
+ cand = seqhead;
+ if((tail_entry = hv_fetch_ent(tails, cand, 0, 0))
+ && (val = HeVAL(tail_entry))
+ && (SvIVx(val) > 0))
+ continue;
+ winner = newSVsv(cand);
+ av_push(retval, winner);
+ }
+ if(!sv_cmp(seqhead, winner)) {
+
+ /* this is basically shift(@seq) in void context */
+ SvREFCNT_dec(*AvARRAY(seq));
+ *AvARRAY(seq) = &PL_sv_undef;
+ AvARRAY(seq) = AvARRAY(seq) + 1;
+ AvMAX(seq)--;
+ AvFILLp(seq)--;
+
+ if(AvFILLp(seq) < 0) continue;
+ svp = av_fetch(seq, 0, 0);
+ seqhead = *svp;
+ tail_entry = hv_fetch_ent(tails, seqhead, 0, 0);
+ val = HeVAL(tail_entry);
+ sv_dec(val);
+ }
+ }
+ if(!cand) break;
+ if(!winner)
+ Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': "
+ "merging failed on parent '%s'", stashname, SvPV_nolen(cand));
+ }
+ }
+
+ SvREADONLY_on(retval);
+ SvREFCNT_inc(retval); /* for cache storage */
+ SvREFCNT_inc(retval); /* for return to caller */
+ /* XXX store in cache storage */
+ return retval;
+}
+
+STATIC I32
+__dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) {
+ I32 i;
+ for (i = startingblock; i >= 0; i--) {
+ if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i;
+ }
+ return i;
+}
+
+STATIC SV*
+__nextcan(pTHX_ SV* self, I32 throw_nomethod)
+{
+ register I32 cxix;
+ register const PERL_CONTEXT *ccstack = cxstack;
+ const PERL_SI *top_si = PL_curstackinfo;
+ HV* selfstash;
+ GV* cvgv;
+ SV *stashname;
+ const char *fq_subname;
+ const char *subname;
+ STRLEN fq_subname_len;
+ STRLEN stashname_len;
+ STRLEN subname_len;
+ SV* sv;
+ GV** gvp;
+ AV* linear_av;
+ SV** linear_svp;
+ SV* linear_sv;
+ HV* cstash;
+ GV* candidate = NULL;
+ CV* cand_cv = NULL;
+ const char *hvname;
+ I32 items;
+ struct mro_meta* selfmeta;
+ HV* nmcache;
+ HE* cache_entry;
+
+ if(sv_isobject(self))
+ selfstash = SvSTASH(SvRV(self));
+ else
+ selfstash = gv_stashsv(self, 0);
+
+ assert(selfstash);
+
+ hvname = HvNAME(selfstash);
+ if (!hvname)
+ croak("Can't use anonymous symbol table for method lookup");
+
+ cxix = __dopoptosub_at(cxstack, cxstack_ix);
+
+ /* This block finds the contextually-enclosing fully-qualified subname,
+ much like looking at (caller($i))[3] until you find a real sub that
+ isn't ANON, etc */
+ for (;;) {
+ /* we may be in a higher stacklevel, so dig down deeper */
+ while (cxix < 0) {
+ if(top_si->si_type == PERLSI_MAIN)
+ croak("next::method/next::can/maybe::next::method must be used in method context");
+ top_si = top_si->si_prev;
+ ccstack = top_si->si_cxstack;
+ cxix = __dopoptosub_at(ccstack, top_si->si_cxix);
+ }
+
+ if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB
+ || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) {
+ cxix = __dopoptosub_at(ccstack, cxix - 1);
+ continue;
+ }
+
+ {
+ const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1);
+ if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) {
+ if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) {
+ cxix = dbcxix;
+ continue;
+ }
+ }
+ }
+
+ cvgv = CvGV(ccstack[cxix].blk_sub.cv);
+
+ if(!isGV(cvgv)) {
+ cxix = __dopoptosub_at(ccstack, cxix - 1);
+ continue;
+ }
+
+ /* we found a real sub here */
+ sv = sv_2mortal(newSV(0));
+
+ gv_efullname3(sv, cvgv, NULL);
+
+ fq_subname = SvPVX(sv);
+ fq_subname_len = SvCUR(sv);
+
+ subname = strrchr(fq_subname, ':');
+ if(!subname)
+ croak("next::method/next::can/maybe::next::method cannot find enclosing method");
+
+ subname++;
+ subname_len = fq_subname_len - (subname - fq_subname);
+ if(subname_len == 8 && strEQ(subname, "__ANON__")) {
+ cxix = __dopoptosub_at(ccstack, cxix - 1);
+ continue;
+ }
+ break;
+ }
+
+ /* If we made it to here, we found our context */
+
+ /*
+ XXX check %next::METHOD_CACHE
+
+ selfmeta = HvMROMETA(selfstash);
+ if(!(nmcache = selfmeta->mro_nextmethod)) {
+ nmcache = selfmeta->mro_nextmethod = newHV();
+ }
+
+ if((cache_entry = hv_fetch_ent(nmcache, sv, 0, 0))) {
+ SV* val = HeVAL(cache_entry);
+ if(val == &PL_sv_undef) {
+ if(throw_nomethod)
+ croak("No next::method '%s' found for %s", subname, hvname);
+ return &PL_sv_undef;
+ }
+ return SvREFCNT_inc(val);
+ }
+ */
+
+ /* beyond here is just for cache misses, so perf isn't as critical */
+
+ stashname_len = subname - fq_subname - 2;
+ stashname = sv_2mortal(newSVpvn(fq_subname, stashname_len));
+
+ linear_av = __mro_linear_isa_c3(selfstash, NULL, 0); /* has ourselves at the top of the list */
+ sv_2mortal((SV*)linear_av);
+
+ linear_svp = AvARRAY(linear_av);
+ items = AvFILLp(linear_av) + 1;
+
+ while (items--) {
+ linear_sv = *linear_svp++;
+ assert(linear_sv);
+ if(sv_eq(linear_sv, stashname))
+ break;
+ }
+
+ if(items > 0) {
+ while (items--) {
+ linear_sv = *linear_svp++;
+ assert(linear_sv);
+ cstash = gv_stashsv(linear_sv, FALSE);
+
+ if (!cstash) {
+ if (ckWARN(WARN_MISC))
+ Perl_warner(aTHX_ packWARN(WARN_MISC), "Can't locate package %"SVf" for @%s::ISA",
+ (void*)linear_sv, hvname);
+ continue;
+ }
+
+ assert(cstash);
+
+/* XXX we need to fetch from %Class::C3::MRO, not the real stash table */
+
+ gvp = (GV**)hv_fetch(cstash, subname, subname_len, 0);
+ if (!gvp) continue;
+
+ candidate = *gvp;
+ assert(candidate);
+
+ if (SvTYPE(candidate) != SVt_PVGV)
+ gv_init(candidate, cstash, subname, subname_len, TRUE);
+ if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
+ SvREFCNT_inc((SV*)cand_cv);
+ /* XXX store result in cache */
+ /* hv_store_ent(nmcache, newSVsv(sv), (SV*)cand_cv, 0); */
+ return (SV*)cand_cv;
+ }
+ }
+ }
+
+ /* XXX store undef in cache */
+ /* hv_store_ent(nmcache, newSVsv(sv), &PL_sv_undef, 0); */
+ if(throw_nomethod)
+ croak("No next::method '%s' found for %s", subname, hvname);
+ return &PL_sv_undef;
+}
+
+XS(XS_Class_C3_XS_calculateMRO);
+XS(XS_Class_C3_XS_calculateMRO)
+{
+#ifdef dVAR
+ dVAR; dXSARGS;
+#else
+ dXSARGS;
+#endif
+
+ SV* classname;
+ HV* class_stash;
+ HV* cache = NULL;
+ AV* res;
+ I32 res_items;
+ I32 ret_items;
+ SV** res_ptr;
+
+ if(items < 1 || items > 2)
+ croak("Usage: calculateMRO(classname[, cache])");
+
+ classname = ST(0);
+ if(items == 2) cache = (HV*)ST(1);
+
+ class_stash = gv_stashsv(classname, 0);
+ if(!class_stash) croak("No such class: '%s'!", SvPV_nolen(classname));
+
+ res = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(class_stash, cache, 0));
+
+
+ res_items = ret_items = AvFILLp(res) + 1;
+ res_ptr = AvARRAY(res);
+
+ SP -= items;
+
+ while(res_items--) {
+ SV* res_item = *res_ptr++;
+ XPUSHs(res_item);
+ }
+
+ PUTBACK;
+
+ return;
+}
+
+XS(XS_next_can);
+XS(XS_next_can)
+{
+#ifdef dVAR
+ dVAR; dXSARGS;
+#else
+ dXSARGS;
+#endif
+
+ SV* self = ST(0);
+ SV* methcv = __nextcan(self, 0);
+
+ PERL_UNUSED_VAR(items);
+
+ if(methcv == &PL_sv_undef) {
+ ST(0) = &PL_sv_undef;
+ }
+ else {
+ ST(0) = sv_2mortal(newRV_inc(methcv));
+ }
+
+ XSRETURN(1);
+}
+
+XS(XS_next_method);
+XS(XS_next_method)
+{
+ dMARK;
+ dAX;
+ SV* self = ST(0);
+ SV* methcv = __nextcan(self, 1);
+
+ PL_markstack_ptr++;
+ call_sv(methcv, GIMME_V);
+}
+
+XS(XS_maybe_next_method);
+XS(XS_maybe_next_method)
+{
+ dMARK;
+ dAX;
+ SV* self = ST(0);
+ SV* methcv = __nextcan(self, 0);
+
+ if(methcv == &PL_sv_undef) {
+ ST(0) = &PL_sv_undef;
+ XSRETURN(1);
+ }
+
+ PL_markstack_ptr++;
+ call_sv(methcv, GIMME_V);
+}
+
+MODULE = Class::C3::XS PACKAGE = Class::C3::XS
+
+BOOT:
+ newXS("Class::C3::XS::calculateMRO", XS_Class_C3_XS_calculateMRO, __FILE__);
+ newXS("next::can", XS_next_can, __FILE__);
+ newXS("next::method", XS_next_method, __FILE__);
+ newXS("maybe::next::method", XS_maybe_next_method, __FILE__);