move XS file to root :p
[gitmo/Class-C3-XS.git] / 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
22c6f594 11/* This is %next::METHOD_CACHE */
12STATIC HV* nmcache;
13
b23e9cb9 14AV*
15__mro_linear_isa_c3(pTHX_ HV* stash, HV* cache, I32 level)
16{
17 AV* retval;
18 GV** gvp;
19 GV* gv;
20 AV* isa;
21 const char* stashname;
22 STRLEN stashname_len;
8995e827 23
b23e9cb9 24 assert(stash);
25 assert(HvAUX(stash));
8995e827 26
b23e9cb9 27 stashname = HvNAME(stash);
28 stashname_len = strlen(stashname);
29 if (!stashname)
30 Perl_croak(aTHX_
31 "Can't linearize anonymous symbol table");
8995e827 32
b23e9cb9 33 if (level > 100)
34 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
35 stashname);
8995e827 36
b23e9cb9 37 if(!cache) {
f0294f1b 38 cache = (HV*)sv_2mortal((SV*)newHV());
b23e9cb9 39 }
40 else {
6bf46d18 41 SV** cache_entry = hv_fetch(cache, stashname, stashname_len, 0);
42 if(cache_entry)
43 return (AV*)SvREFCNT_inc(*cache_entry);
b23e9cb9 44 }
45
46 /* not in cache, make a new one */
47
48 retval = (AV*)sv_2mortal((SV*)newAV());
49 av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */
50
51 gvp = (GV**)hv_fetch(stash, "ISA", 3, FALSE);
52 isa = (gvp && (gv = *gvp) && gv != (GV*)&PL_sv_undef) ? GvAV(gv) : NULL;
53
54 if(isa && AvFILLp(isa) >= 0) {
55 SV** seqs_ptr;
56 I32 seqs_items;
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);
61 while(items--) {
62 AV* isa_lin;
63 SV* isa_item = *isa_ptr++;
64 HV* isa_item_stash = gv_stashsv(isa_item, 0);
65 if(!isa_item_stash) {
66 isa_lin = newAV();
67 av_push(isa_lin, newSVsv(isa_item));
68 }
69 else {
b36f79e1 70 isa_lin = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ isa_item_stash, cache, level + 1)); /* recursion */
b23e9cb9 71 }
72 av_push(seqs, (SV*)av_make(AvFILLp(isa_lin)+1, AvARRAY(isa_lin)));
73 }
74 av_push(seqs, (SV*)av_make(AvFILLp(isa)+1, AvARRAY(isa)));
75
76 seqs_ptr = AvARRAY(seqs);
77 seqs_items = AvFILLp(seqs) + 1;
78 while(seqs_items--) {
79 AV* seq = (AV*)*seqs_ptr++;
80 I32 seq_items = AvFILLp(seq);
81 if(seq_items > 0) {
82 SV** seq_ptr = AvARRAY(seq) + 1;
83 while(seq_items--) {
84 SV* seqitem = *seq_ptr++;
85 HE* he = hv_fetch_ent(tails, seqitem, 0, 0);
86 if(!he) {
87 hv_store_ent(tails, seqitem, newSViv(1), 0);
88 }
89 else {
90 SV* val = HeVAL(he);
91 sv_inc(val);
92 }
93 }
94 }
95 }
96
97 while(1) {
98 SV* seqhead = NULL;
99 SV* cand = NULL;
100 SV* winner = NULL;
101 SV* val;
102 HE* tail_entry;
103 AV* seq;
104 SV** avptr = AvARRAY(seqs);
105 items = AvFILLp(seqs)+1;
106 while(items--) {
107 SV** svp;
108 seq = (AV*)*avptr++;
109 if(AvFILLp(seq) < 0) continue;
110 svp = av_fetch(seq, 0, 0);
111 seqhead = *svp;
112 if(!winner) {
113 cand = seqhead;
114 if((tail_entry = hv_fetch_ent(tails, cand, 0, 0))
115 && (val = HeVAL(tail_entry))
116 && (SvIVx(val) > 0))
117 continue;
118 winner = newSVsv(cand);
119 av_push(retval, winner);
120 }
121 if(!sv_cmp(seqhead, winner)) {
122
123 /* this is basically shift(@seq) in void context */
124 SvREFCNT_dec(*AvARRAY(seq));
125 *AvARRAY(seq) = &PL_sv_undef;
126 AvARRAY(seq) = AvARRAY(seq) + 1;
127 AvMAX(seq)--;
128 AvFILLp(seq)--;
129
130 if(AvFILLp(seq) < 0) continue;
131 svp = av_fetch(seq, 0, 0);
132 seqhead = *svp;
133 tail_entry = hv_fetch_ent(tails, seqhead, 0, 0);
134 val = HeVAL(tail_entry);
135 sv_dec(val);
136 }
137 }
138 if(!cand) break;
139 if(!winner)
140 Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': "
141 "merging failed on parent '%s'", stashname, SvPV_nolen(cand));
142 }
143 }
144
145 SvREADONLY_on(retval);
146 SvREFCNT_inc(retval); /* for cache storage */
6bf46d18 147 SvREFCNT_inc(retval); /* for return */
f0294f1b 148 hv_store(cache, stashname, stashname_len, (SV*)retval, 0);
b23e9cb9 149 return retval;
150}
151
152STATIC I32
153__dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) {
154 I32 i;
155 for (i = startingblock; i >= 0; i--) {
156 if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i;
157 }
158 return i;
159}
160
161STATIC SV*
162__nextcan(pTHX_ SV* self, I32 throw_nomethod)
163{
164 register I32 cxix;
165 register const PERL_CONTEXT *ccstack = cxstack;
166 const PERL_SI *top_si = PL_curstackinfo;
167 HV* selfstash;
168 GV* cvgv;
169 SV *stashname;
170 const char *fq_subname;
171 const char *subname;
172 STRLEN fq_subname_len;
173 STRLEN stashname_len;
174 STRLEN subname_len;
175 SV* sv;
176 GV** gvp;
177 AV* linear_av;
178 SV** linear_svp;
179 SV* linear_sv;
180 HV* cstash;
181 GV* candidate = NULL;
182 CV* cand_cv = NULL;
183 const char *hvname;
184 I32 items;
b23e9cb9 185 HE* cache_entry;
22c6f594 186 SV* cachekey;
b23e9cb9 187
188 if(sv_isobject(self))
189 selfstash = SvSTASH(SvRV(self));
190 else
191 selfstash = gv_stashsv(self, 0);
192
193 assert(selfstash);
194
195 hvname = HvNAME(selfstash);
196 if (!hvname)
197 croak("Can't use anonymous symbol table for method lookup");
198
199 cxix = __dopoptosub_at(cxstack, cxstack_ix);
200
201 /* This block finds the contextually-enclosing fully-qualified subname,
202 much like looking at (caller($i))[3] until you find a real sub that
203 isn't ANON, etc */
204 for (;;) {
205 /* we may be in a higher stacklevel, so dig down deeper */
206 while (cxix < 0) {
207 if(top_si->si_type == PERLSI_MAIN)
208 croak("next::method/next::can/maybe::next::method must be used in method context");
209 top_si = top_si->si_prev;
210 ccstack = top_si->si_cxstack;
211 cxix = __dopoptosub_at(ccstack, top_si->si_cxix);
212 }
213
214 if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB
215 || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) {
216 cxix = __dopoptosub_at(ccstack, cxix - 1);
217 continue;
218 }
219
220 {
221 const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1);
222 if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) {
223 if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) {
224 cxix = dbcxix;
225 continue;
226 }
227 }
228 }
229
230 cvgv = CvGV(ccstack[cxix].blk_sub.cv);
231
232 if(!isGV(cvgv)) {
233 cxix = __dopoptosub_at(ccstack, cxix - 1);
234 continue;
235 }
236
237 /* we found a real sub here */
238 sv = sv_2mortal(newSV(0));
239
240 gv_efullname3(sv, cvgv, NULL);
241
242 fq_subname = SvPVX(sv);
243 fq_subname_len = SvCUR(sv);
244
245 subname = strrchr(fq_subname, ':');
246 if(!subname)
247 croak("next::method/next::can/maybe::next::method cannot find enclosing method");
248
249 subname++;
250 subname_len = fq_subname_len - (subname - fq_subname);
251 if(subname_len == 8 && strEQ(subname, "__ANON__")) {
252 cxix = __dopoptosub_at(ccstack, cxix - 1);
253 continue;
254 }
255 break;
256 }
257
258 /* If we made it to here, we found our context */
259
22c6f594 260 /* cachekey = "objpkg|context::method::name" */
261 cachekey = sv_2mortal(newSVpv(hvname, 0));
262 sv_catpvn(cachekey, "|", 1);
263 sv_catsv(cachekey, sv);
b23e9cb9 264
22c6f594 265 if((cache_entry = hv_fetch_ent(nmcache, cachekey, 0, 0))) {
b23e9cb9 266 SV* val = HeVAL(cache_entry);
267 if(val == &PL_sv_undef) {
268 if(throw_nomethod)
269 croak("No next::method '%s' found for %s", subname, hvname);
270 return &PL_sv_undef;
271 }
272 return SvREFCNT_inc(val);
273 }
b23e9cb9 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
b36f79e1 280 linear_av = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ selfstash, NULL, 0));
b23e9cb9 281
282 linear_svp = AvARRAY(linear_av);
283 items = AvFILLp(linear_av) + 1;
284
285 while (items--) {
286 linear_sv = *linear_svp++;
287 assert(linear_sv);
288 if(sv_eq(linear_sv, stashname))
289 break;
290 }
291
292 if(items > 0) {
29e61e10 293 SV* sub_sv = sv_2mortal(newSVpv(subname, subname_len));
294 HV* cc3_mro = get_hv("Class::C3::MRO", 0);
29e61e10 295
b23e9cb9 296 while (items--) {
297 linear_sv = *linear_svp++;
298 assert(linear_sv);
29e61e10 299
300 if(cc3_mro) {
301 HE* he_cc3_mro_class = hv_fetch_ent(cc3_mro, linear_sv, 0, 0);
302 if(he_cc3_mro_class) {
efafd620 303 HV* cc3_mro_class = (HV*)SvRV(HeVAL(he_cc3_mro_class));
304 SV** svp_cc3_mro_class_methods = hv_fetch(cc3_mro_class, "methods", 7, 0);
305 if(svp_cc3_mro_class_methods) {
306 HV* cc3_mro_class_methods = (HV*)SvRV(*svp_cc3_mro_class_methods);
29e61e10 307 if(hv_exists_ent(cc3_mro_class_methods, sub_sv, 0))
308 continue;
309 }
310 }
311 }
312
b23e9cb9 313 cstash = gv_stashsv(linear_sv, FALSE);
314
315 if (!cstash) {
316 if (ckWARN(WARN_MISC))
317 Perl_warner(aTHX_ packWARN(WARN_MISC), "Can't locate package %"SVf" for @%s::ISA",
318 (void*)linear_sv, hvname);
319 continue;
320 }
321
322 assert(cstash);
323
b23e9cb9 324 gvp = (GV**)hv_fetch(cstash, subname, subname_len, 0);
325 if (!gvp) continue;
326
327 candidate = *gvp;
328 assert(candidate);
329
330 if (SvTYPE(candidate) != SVt_PVGV)
331 gv_init(candidate, cstash, subname, subname_len, TRUE);
332 if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) {
333 SvREFCNT_inc((SV*)cand_cv);
22c6f594 334 hv_store_ent(nmcache, newSVsv(cachekey), (SV*)cand_cv, 0);
b23e9cb9 335 return (SV*)cand_cv;
336 }
337 }
338 }
339
22c6f594 340 hv_store_ent(nmcache, newSVsv(cachekey), &PL_sv_undef, 0);
b23e9cb9 341 if(throw_nomethod)
342 croak("No next::method '%s' found for %s", subname, hvname);
343 return &PL_sv_undef;
344}
345
346XS(XS_Class_C3_XS_calculateMRO);
347XS(XS_Class_C3_XS_calculateMRO)
348{
349#ifdef dVAR
350 dVAR; dXSARGS;
351#else
352 dXSARGS;
353#endif
354
355 SV* classname;
356 HV* class_stash;
357 HV* cache = NULL;
358 AV* res;
359 I32 res_items;
360 I32 ret_items;
361 SV** res_ptr;
362
363 if(items < 1 || items > 2)
364 croak("Usage: calculateMRO(classname[, cache])");
365
366 classname = ST(0);
f0294f1b 367 if(items == 2) cache = (HV*)SvRV(ST(1));
b23e9cb9 368
369 class_stash = gv_stashsv(classname, 0);
370 if(!class_stash) croak("No such class: '%s'!", SvPV_nolen(classname));
371
b36f79e1 372 res = (AV*)sv_2mortal((SV*)__mro_linear_isa_c3(aTHX_ class_stash, cache, 0));
b23e9cb9 373
b23e9cb9 374 res_items = ret_items = AvFILLp(res) + 1;
375 res_ptr = AvARRAY(res);
376
377 SP -= items;
378
379 while(res_items--) {
380 SV* res_item = *res_ptr++;
381 XPUSHs(res_item);
382 }
383
384 PUTBACK;
385
386 return;
387}
388
389XS(XS_next_can);
390XS(XS_next_can)
391{
392#ifdef dVAR
393 dVAR; dXSARGS;
394#else
395 dXSARGS;
396#endif
397
398 SV* self = ST(0);
b36f79e1 399 SV* methcv = __nextcan(aTHX_ self, 0);
b23e9cb9 400
401 PERL_UNUSED_VAR(items);
402
403 if(methcv == &PL_sv_undef) {
404 ST(0) = &PL_sv_undef;
405 }
406 else {
407 ST(0) = sv_2mortal(newRV_inc(methcv));
408 }
409
410 XSRETURN(1);
411}
412
413XS(XS_next_method);
414XS(XS_next_method)
415{
416 dMARK;
417 dAX;
418 SV* self = ST(0);
b36f79e1 419 SV* methcv = __nextcan(aTHX_ self, 1);
b23e9cb9 420
421 PL_markstack_ptr++;
422 call_sv(methcv, GIMME_V);
423}
424
425XS(XS_maybe_next_method);
426XS(XS_maybe_next_method)
427{
428 dMARK;
429 dAX;
430 SV* self = ST(0);
b36f79e1 431 SV* methcv = __nextcan(aTHX_ self, 0);
b23e9cb9 432
433 if(methcv == &PL_sv_undef) {
434 ST(0) = &PL_sv_undef;
435 XSRETURN(1);
436 }
437
438 PL_markstack_ptr++;
439 call_sv(methcv, GIMME_V);
440}
441
442MODULE = Class::C3::XS PACKAGE = Class::C3::XS
443
444BOOT:
22c6f594 445 nmcache = get_hv("next::METHOD_CACHE", 1);
b23e9cb9 446 newXS("Class::C3::XS::calculateMRO", XS_Class_C3_XS_calculateMRO, __FILE__);
447 newXS("next::can", XS_next_can, __FILE__);
448 newXS("next::method", XS_next_method, __FILE__);
449 newXS("maybe::next::method", XS_maybe_next_method, __FILE__);