halfway there on the next::method issue
[gitmo/Class-C3-XS.git] / lib / Class / C3 / XS.xs
CommitLineData
8995e827 1
2#include "EXTERN.h"
3#include "perl.h"
4#include "XSUB.h"
8995e827 5
29e61e10 6/* Most of this code is backported from the bleadperl patch's
b23e9cb9 7 mro.c, and then modified to work with Class::C3's
8 internals.
9*/
8995e827 10
b23e9cb9 11AV*
12__mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level)
13{
14 AV* retval;
15 GV** gvp;
16 GV* gv;
17 AV* isa;
18 const char* stashname;
19 STRLEN stashname_len;
8995e827 20
b23e9cb9 21 assert(stash);
22 assert(HvAUX(stash));
8995e827 23
b23e9cb9 24 stashname = HvNAME(stash);
25 stashname_len = strlen(stashname);
26 if (!stashname)
27 Perl_croak(aTHX_
28 "Can't linearize anonymous symbol table");
8995e827 29
b23e9cb9 30 if (level > 100)
31 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
32 stashname);
8995e827 33
b23e9cb9 34 if(!cache) {
35 cache = newHV();
36 }
37 else {
38 /* XXX return cached entry for stashname if available */
39 }
40
41 /* not in cache, make a new one */
42
43 retval = (AV*)sv_2mortal((SV*)newAV());
44 av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */
45
46 gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE);
47 isa = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : NULL;
48
49 if(isa && AvFILLp(isa) >= 0) {
50 SV** seqs_ptr;
51 I32 seqs_items;
52 HV* tails = (HV*)sv_2mortal((SV*)newHV());
53 AV* seqs = (AV*)sv_2mortal((SV*)newAV());
54 I32 items = AvFILLp(isa) + 1;
55 SV** isa_ptr = AvARRAY(isa);
56 while(items--) {
57 AV* isa_lin;
58 SV* isa_item = *isa_ptr++;
59 HV* isa_item_stash = gv_stashsv(isa_item, 0);
60 if(!isa_item_stash) {
61 isa_lin = newAV();
62 av_push(isa_lin, newSVsv(isa_item));
63 }
64 else {
65 isa_lin = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(isa_item_stash, cache, level + 1)); /* recursion */
66 }
67 av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin)));
68 }
69 av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa)));
70
71 seqs_ptr = AvARRAY(seqs);
72 seqs_items = AvFILLp(seqs) + 1;
73 while(seqs_items--) {
74 AV* seq = (AV*)*seqs_ptr++;
75 I32 seq_items = AvFILLp(seq);
76 if(seq_items > 0) {
77 SV** seq_ptr = AvARRAY(seq) + 1;
78 while(seq_items--) {
79 SV* seqitem = *seq_ptr++;
80 HE* he = hv_fetch_ent(tails, seqitem, 0, 0);
81 if(!he) {
82 hv_store_ent(tails, seqitem, newSViv(1), 0);
83 }
84 else {
85 SV* val = HeVAL(he);
86 sv_inc(val);
87 }
88 }
89 }
90 }
91
92 while(1) {
93 SV* seqhead = NULL;
94 SV* cand = NULL;
95 SV* winner = NULL;
96 SV* val;
97 HE* tail_entry;
98 AV* seq;
99 SV** avptr = AvARRAY(seqs);
100 items = AvFILLp(seqs)+1;
101 while(items--) {
102 SV** svp;
103 seq = (AV*)*avptr++;
104 if(AvFILLp(seq) < 0) continue;
105 svp = av_fetch(seq, 0, 0);
106 seqhead = *svp;
107 if(!winner) {
108 cand = seqhead;
109 if((tail_entry = hv_fetch_ent(tails, cand, 0, 0))
110 && (val = HeVAL(tail_entry))
111 && (SvIVx(val) > 0))
112 continue;
113 winner = newSVsv(cand);
114 av_push(retval, winner);
115 }
116 if(!sv_cmp(seqhead, winner)) {
117
118 /* this is basically shift(@seq) in void context */
119 SvREFCNT_dec(*AvARRAY(seq));
120 *AvARRAY(seq) = &PL_sv_undef;
121 AvARRAY(seq) = AvARRAY(seq) + 1;
122 AvMAX(seq)--;
123 AvFILLp(seq)--;
124
125 if(AvFILLp(seq) < 0) continue;
126 svp = av_fetch(seq, 0, 0);
127 seqhead = *svp;
128 tail_entry = hv_fetch_ent(tails, seqhead, 0, 0);
129 val = HeVAL(tail_entry);
130 sv_dec(val);
131 }
132 }
133 if(!cand) break;
134 if(!winner)
135 Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': "
136 "merging failed on parent '%s'", stashname, SvPV_nolen(cand));
137 }
138 }
139
140 SvREADONLY_on(retval);
141 SvREFCNT_inc(retval); /* for cache storage */
142 SvREFCNT_inc(retval); /* for return to caller */
143 /* XXX store in cache storage */
144 return retval;
145}
146
147STATIC I32
148__dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) {
149 I32 i;
150 for (i = startingblock; i >= 0; i--) {
151 if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i;
152 }
153 return i;
154}
155
156STATIC SV*
157__nextcan(pTHX_ SV* self, I32 throw_nomethod)
158{
159 register I32 cxix;
160 register const PERL_CONTEXT *ccstack = cxstack;
161 const PERL_SI *top_si = PL_curstackinfo;
162 HV* selfstash;
163 GV* cvgv;
164 SV *stashname;
165 const char *fq_subname;
166 const char *subname;
167 STRLEN fq_subname_len;
168 STRLEN stashname_len;
169 STRLEN subname_len;
170 SV* sv;
171 GV** gvp;
172 AV* linear_av;
173 SV** linear_svp;
174 SV* linear_sv;
175 HV* cstash;
176 GV* candidate = NULL;
177 CV* cand_cv = NULL;
178 const char *hvname;
179 I32 items;
180 struct mro_meta* selfmeta;
181 HV* nmcache;
182 HE* cache_entry;
183
184 if(sv_isobject(self))
185 selfstash = SvSTASH(SvRV(self));
186 else
187 selfstash = gv_stashsv(self, 0);
188
189 assert(selfstash);
190
191 hvname = HvNAME(selfstash);
192 if (!hvname)
193 croak("Can't use anonymous symbol table for method lookup");
194
195 cxix = __dopoptosub_at(cxstack, cxstack_ix);
196
197 /* This block finds the contextually-enclosing fully-qualified subname,
198 much like looking at (caller($i))[3] until you find a real sub that
199 isn't ANON, etc */
200 for (;;) {
201 /* we may be in a higher stacklevel, so dig down deeper */
202 while (cxix < 0) {
203 if(top_si->si_type == PERLSI_MAIN)
204 croak("next::method/next::can/maybe::next::method must be used in method context");
205 top_si = top_si->si_prev;
206 ccstack = top_si->si_cxstack;
207 cxix = __dopoptosub_at(ccstack, top_si->si_cxix);
208 }
209
210 if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB
211 || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) {
212 cxix = __dopoptosub_at(ccstack, cxix - 1);
213 continue;
214 }
215
216 {
217 const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1);
218 if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) {
219 if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) {
220 cxix = dbcxix;
221 continue;
222 }
223 }
224 }
225
226 cvgv = CvGV(ccstack[cxix].blk_sub.cv);
227
228 if(!isGV(cvgv)) {
229 cxix = __dopoptosub_at(ccstack, cxix - 1);
230 continue;
231 }
232
233 /* we found a real sub here */
234 sv = sv_2mortal(newSV(0));
235
236 gv_efullname3(sv, cvgv, NULL);
237
238 fq_subname = SvPVX(sv);
239 fq_subname_len = SvCUR(sv);
240
241 subname = strrchr(fq_subname, ':');
242 if(!subname)
243 croak("next::method/next::can/maybe::next::method cannot find enclosing method");
244
245 subname++;
246 subname_len = fq_subname_len - (subname - fq_subname);
247 if(subname_len == 8 && strEQ(subname, "__ANON__")) {
248 cxix = __dopoptosub_at(ccstack, cxix - 1);
249 continue;
250 }
251 break;
252 }
253
254 /* If we made it to here, we found our context */
255
256 /*
257 XXX check %next::METHOD_CACHE
258
259 selfmeta = HvMROMETA(selfstash);
260 if(!(nmcache = selfmeta->mro_nextmethod)) {
261 nmcache = selfmeta->mro_nextmethod = newHV();
262 }
263
264 if((cache_entry = hv_fetch_ent(nmcache, sv, 0, 0))) {
265 SV* val = HeVAL(cache_entry);
266 if(val == &PL_sv_undef) {
267 if(throw_nomethod)
268 croak("No next::method '%s' found for %s", subname, hvname);
269 return &PL_sv_undef;
270 }
271 return SvREFCNT_inc(val);
272 }
273 */
274
275 /* beyond here is just for cache misses, so perf isn't as critical */
276
277 stashname_len = subname - fq_subname - 2;
278 stashname = sv_2mortal(newSVpvn(fq_subname, stashname_len));
279
280 linear_av = __mro_linear_isa_c3(selfstash, NULL, 0); /* has ourselves at the top of the list */
281 sv_2mortal((SV*)linear_av);
282
283 linear_svp = AvARRAY(linear_av);
284 items = AvFILLp(linear_av) + 1;
285
286 while (items--) {
287 linear_sv = *linear_svp++;
288 assert(linear_sv);
289 if(sv_eq(linear_sv, stashname))
290 break;
291 }
292
293 if(items > 0) {
29e61e10 294 SV* sub_sv = sv_2mortal(newSVpv(subname, subname_len));
295 HV* cc3_mro = get_hv("Class::C3::MRO", 0);
296 SV* methods = sv_2mortal(newSVpv("methods", 7));
297
b23e9cb9 298 while (items--) {
299 linear_sv = *linear_svp++;
300 assert(linear_sv);
29e61e10 301
302 if(cc3_mro) {
303 HE* he_cc3_mro_class = hv_fetch_ent(cc3_mro, linear_sv, 0, 0);
304 if(he_cc3_mro_class) {
305 HV* cc3_mro_class = (HV*)HeVAL(he_cc3_mro_class);
306 HE* he_cc3_mro_class_methods = hv_fetch_ent(cc3_mro_class, methods, 0, 0);
307 if(he_cc3_mro_class_methods) {
308 HV* cc3_mro_class_methods = (HV*)HeVAL(he_cc3_mro_class_methods);
309 if(hv_exists_ent(cc3_mro_class_methods, sub_sv, 0))
310 continue;
311 }
312 }
313 }
314
b23e9cb9 315 cstash = gv_stashsv(linear_sv, FALSE);
316
317 if (!cstash) {
318 if (ckWARN(WARN_MISC))
319 Perl_warner(aTHX_ packWARN(WARN_MISC), "Can't locate package %"SVf" for @%s::ISA",
320 (void*)linear_sv, hvname);
321 continue;
322 }
323
324 assert(cstash);
325
b23e9cb9 326 gvp = (GV**)hv_fetch(cstash, subname, subname_len, 0);
327 if (!gvp) continue;
328
329 candidate = *gvp;
330 assert(candidate);
331
332 if (SvTYPE(candidate) != SVt_PVGV)
333 gv_init(candidate, cstash, subname, subname_len, TRUE);
334 if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
335 SvREFCNT_inc((SV*)cand_cv);
336 /* XXX store result in cache */
337 /* hv_store_ent(nmcache, newSVsv(sv), (SV*)cand_cv, 0); */
338 return (SV*)cand_cv;
339 }
340 }
341 }
342
343 /* XXX store undef in cache */
344 /* hv_store_ent(nmcache, newSVsv(sv), &PL_sv_undef, 0); */
345 if(throw_nomethod)
346 croak("No next::method '%s' found for %s", subname, hvname);
347 return &PL_sv_undef;
348}
349
350XS(XS_Class_C3_XS_calculateMRO);
351XS(XS_Class_C3_XS_calculateMRO)
352{
353#ifdef dVAR
354 dVAR; dXSARGS;
355#else
356 dXSARGS;
357#endif
358
359 SV* classname;
360 HV* class_stash;
361 HV* cache = NULL;
362 AV* res;
363 I32 res_items;
364 I32 ret_items;
365 SV** res_ptr;
366
367 if(items < 1 || items > 2)
368 croak("Usage: calculateMRO(classname[, cache])");
369
370 classname = ST(0);
371 if(items == 2) cache = (HV*)ST(1);
372
373 class_stash = gv_stashsv(classname, 0);
374 if(!class_stash) croak("No such class: '%s'!", SvPV_nolen(classname));
375
376 res = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(class_stash, cache, 0));
377
378
379 res_items = ret_items = AvFILLp(res) + 1;
380 res_ptr = AvARRAY(res);
381
382 SP -= items;
383
384 while(res_items--) {
385 SV* res_item = *res_ptr++;
386 XPUSHs(res_item);
387 }
388
389 PUTBACK;
390
391 return;
392}
393
394XS(XS_next_can);
395XS(XS_next_can)
396{
397#ifdef dVAR
398 dVAR; dXSARGS;
399#else
400 dXSARGS;
401#endif
402
403 SV* self = ST(0);
404 SV* methcv = __nextcan(self, 0);
405
406 PERL_UNUSED_VAR(items);
407
408 if(methcv == &PL_sv_undef) {
409 ST(0) = &PL_sv_undef;
410 }
411 else {
412 ST(0) = sv_2mortal(newRV_inc(methcv));
413 }
414
415 XSRETURN(1);
416}
417
418XS(XS_next_method);
419XS(XS_next_method)
420{
421 dMARK;
422 dAX;
423 SV* self = ST(0);
424 SV* methcv = __nextcan(self, 1);
425
426 PL_markstack_ptr++;
427 call_sv(methcv, GIMME_V);
428}
429
430XS(XS_maybe_next_method);
431XS(XS_maybe_next_method)
432{
433 dMARK;
434 dAX;
435 SV* self = ST(0);
436 SV* methcv = __nextcan(self, 0);
437
438 if(methcv == &PL_sv_undef) {
439 ST(0) = &PL_sv_undef;
440 XSRETURN(1);
441 }
442
443 PL_markstack_ptr++;
444 call_sv(methcv, GIMME_V);
445}
446
447MODULE = Class::C3::XS PACKAGE = Class::C3::XS
448
449BOOT:
450 newXS("Class::C3::XS::calculateMRO", XS_Class_C3_XS_calculateMRO, __FILE__);
451 newXS("next::can", XS_next_can, __FILE__);
452 newXS("next::method", XS_next_method, __FILE__);
453 newXS("maybe::next::method", XS_maybe_next_method, __FILE__);