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e1a479c5 BB |
1 | /* mro.c |
2 | * | |
3 | * Copyright (c) 2007 Brandon L Black | |
4 | * | |
5 | * You may distribute under the terms of either the GNU General Public | |
6 | * License or the Artistic License, as specified in the README file. | |
7 | * | |
8 | */ | |
9 | ||
10 | /* | |
cac98860 RGS |
11 | * "Which order shall we go in?" said Frodo. "Eldest first, or quickest first? |
12 | * You'll be last either way, Master Peregrin." | |
13 | */ | |
14 | ||
15 | /* | |
e1a479c5 BB |
16 | =head1 MRO Functions |
17 | ||
18 | These functions are related to the method resolution order of perl classes | |
19 | ||
20 | =cut | |
21 | */ | |
22 | ||
23 | #include "EXTERN.h" | |
24 | #include "perl.h" | |
25 | ||
26 | struct mro_meta* | |
27 | Perl_mro_meta_init(pTHX_ HV* stash) | |
28 | { | |
9fe4aecf | 29 | struct mro_meta* newmeta; |
e1a479c5 BB |
30 | |
31 | assert(stash); | |
32 | assert(HvAUX(stash)); | |
33 | assert(!(HvAUX(stash)->xhv_mro_meta)); | |
183086be | 34 | Newxz(newmeta, 1, struct mro_meta); |
9fe4aecf | 35 | HvAUX(stash)->xhv_mro_meta = newmeta; |
dd69841b | 36 | newmeta->cache_gen = 1; |
70cd14a1 | 37 | newmeta->pkg_gen = 1; |
e1a479c5 BB |
38 | |
39 | return newmeta; | |
40 | } | |
41 | ||
42 | #if defined(USE_ITHREADS) | |
43 | ||
44 | /* for sv_dup on new threads */ | |
45 | struct mro_meta* | |
46 | Perl_mro_meta_dup(pTHX_ struct mro_meta* smeta, CLONE_PARAMS* param) | |
47 | { | |
e1a479c5 BB |
48 | struct mro_meta* newmeta; |
49 | ||
50 | assert(smeta); | |
51 | ||
33e12d9d NC |
52 | Newx(newmeta, 1, struct mro_meta); |
53 | Copy(smeta, newmeta, 1, struct mro_meta); | |
54 | ||
55 | if (newmeta->mro_linear_dfs) | |
56 | newmeta->mro_linear_dfs | |
57 | = (AV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_linear_dfs, param)); | |
58 | if (newmeta->mro_linear_c3) | |
59 | newmeta->mro_linear_c3 | |
60 | = (AV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_linear_c3, param)); | |
33e12d9d NC |
61 | if (newmeta->mro_nextmethod) |
62 | newmeta->mro_nextmethod | |
63 | = (HV*) SvREFCNT_inc(sv_dup((SV*)newmeta->mro_nextmethod, param)); | |
e1a479c5 BB |
64 | |
65 | return newmeta; | |
66 | } | |
67 | ||
68 | #endif /* USE_ITHREADS */ | |
69 | ||
70 | /* | |
71 | =for apidoc mro_get_linear_isa_dfs | |
72 | ||
73 | Returns the Depth-First Search linearization of @ISA | |
74 | the given stash. The return value is a read-only AV*. | |
75 | C<level> should be 0 (it is used internally in this | |
76 | function's recursion). | |
77 | ||
1c908217 RGS |
78 | You are responsible for C<SvREFCNT_inc()> on the |
79 | return value if you plan to store it anywhere | |
80 | semi-permanently (otherwise it might be deleted | |
81 | out from under you the next time the cache is | |
82 | invalidated). | |
83 | ||
e1a479c5 BB |
84 | =cut |
85 | */ | |
86 | AV* | |
87 | Perl_mro_get_linear_isa_dfs(pTHX_ HV *stash, I32 level) | |
88 | { | |
89 | AV* retval; | |
90 | GV** gvp; | |
91 | GV* gv; | |
92 | AV* av; | |
e1a479c5 BB |
93 | const char* stashname; |
94 | struct mro_meta* meta; | |
95 | ||
96 | assert(stash); | |
97 | assert(HvAUX(stash)); | |
98 | ||
99 | stashname = HvNAME_get(stash); | |
100 | if (!stashname) | |
1e05feb3 | 101 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); |
e1a479c5 BB |
102 | |
103 | if (level > 100) | |
104 | Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", | |
105 | stashname); | |
106 | ||
107 | meta = HvMROMETA(stash); | |
1c908217 RGS |
108 | |
109 | /* return cache if valid */ | |
e1a479c5 | 110 | if((retval = meta->mro_linear_dfs)) { |
e1a479c5 BB |
111 | return retval; |
112 | } | |
113 | ||
114 | /* not in cache, make a new one */ | |
1c908217 | 115 | |
e1a479c5 BB |
116 | retval = newAV(); |
117 | av_push(retval, newSVpv(stashname, 0)); /* add ourselves at the top */ | |
118 | ||
1c908217 | 119 | /* fetch our @ISA */ |
e1a479c5 BB |
120 | gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); |
121 | av = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; | |
122 | ||
640da897 | 123 | if(av && AvFILLp(av) >= 0) { |
1c908217 RGS |
124 | |
125 | /* "stored" is used to keep track of all of the classnames | |
126 | we have added to the MRO so far, so we can do a quick | |
127 | exists check and avoid adding duplicate classnames to | |
128 | the MRO as we go. */ | |
129 | ||
1e05feb3 | 130 | HV* const stored = (HV*)sv_2mortal((SV*)newHV()); |
ffd8da72 NC |
131 | SV **svp = AvARRAY(av); |
132 | I32 items = AvFILLp(av) + 1; | |
1c908217 RGS |
133 | |
134 | /* foreach(@ISA) */ | |
e1a479c5 BB |
135 | while (items--) { |
136 | SV* const sv = *svp++; | |
137 | HV* const basestash = gv_stashsv(sv, 0); | |
ffd8da72 NC |
138 | SV *const *subrv_p; |
139 | I32 subrv_items; | |
e1a479c5 BB |
140 | |
141 | if (!basestash) { | |
1c908217 RGS |
142 | /* if no stash exists for this @ISA member, |
143 | simply add it to the MRO and move on */ | |
ffd8da72 NC |
144 | subrv_p = &sv; |
145 | subrv_items = 1; | |
e1a479c5 BB |
146 | } |
147 | else { | |
1c908217 RGS |
148 | /* otherwise, recurse into ourselves for the MRO |
149 | of this @ISA member, and append their MRO to ours */ | |
ffd8da72 NC |
150 | const AV *const subrv |
151 | = mro_get_linear_isa_dfs(basestash, level + 1); | |
152 | ||
153 | subrv_p = AvARRAY(subrv); | |
154 | subrv_items = AvFILLp(subrv) + 1; | |
155 | } | |
156 | while(subrv_items--) { | |
157 | SV *const subsv = *subrv_p++; | |
158 | if(!hv_exists_ent(stored, subsv, 0)) { | |
ffd8da72 | 159 | hv_store_ent(stored, subsv, &PL_sv_undef, 0); |
25270bc0 | 160 | av_push(retval, newSVsv(subsv)); |
ffd8da72 | 161 | } |
e1a479c5 BB |
162 | } |
163 | } | |
164 | } | |
165 | ||
1c908217 RGS |
166 | /* we don't want anyone modifying the cache entry but us, |
167 | and we do so by replacing it completely */ | |
e1a479c5 | 168 | SvREADONLY_on(retval); |
1c908217 | 169 | |
e1a479c5 BB |
170 | meta->mro_linear_dfs = retval; |
171 | return retval; | |
172 | } | |
173 | ||
174 | /* | |
175 | =for apidoc mro_get_linear_isa_c3 | |
176 | ||
177 | Returns the C3 linearization of @ISA | |
178 | the given stash. The return value is a read-only AV*. | |
179 | C<level> should be 0 (it is used internally in this | |
180 | function's recursion). | |
181 | ||
1c908217 RGS |
182 | You are responsible for C<SvREFCNT_inc()> on the |
183 | return value if you plan to store it anywhere | |
184 | semi-permanently (otherwise it might be deleted | |
185 | out from under you the next time the cache is | |
186 | invalidated). | |
187 | ||
e1a479c5 BB |
188 | =cut |
189 | */ | |
190 | ||
191 | AV* | |
192 | Perl_mro_get_linear_isa_c3(pTHX_ HV* stash, I32 level) | |
193 | { | |
194 | AV* retval; | |
195 | GV** gvp; | |
196 | GV* gv; | |
197 | AV* isa; | |
198 | const char* stashname; | |
199 | STRLEN stashname_len; | |
200 | struct mro_meta* meta; | |
201 | ||
202 | assert(stash); | |
203 | assert(HvAUX(stash)); | |
204 | ||
205 | stashname = HvNAME_get(stash); | |
206 | stashname_len = HvNAMELEN_get(stash); | |
207 | if (!stashname) | |
1e05feb3 | 208 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); |
e1a479c5 BB |
209 | |
210 | if (level > 100) | |
211 | Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", | |
212 | stashname); | |
213 | ||
214 | meta = HvMROMETA(stash); | |
1c908217 RGS |
215 | |
216 | /* return cache if valid */ | |
e1a479c5 | 217 | if((retval = meta->mro_linear_c3)) { |
e1a479c5 BB |
218 | return retval; |
219 | } | |
220 | ||
221 | /* not in cache, make a new one */ | |
222 | ||
e1a479c5 BB |
223 | gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); |
224 | isa = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; | |
225 | ||
1c908217 RGS |
226 | /* For a better idea how the rest of this works, see the much clearer |
227 | pure perl version in Algorithm::C3 0.01: | |
228 | http://search.cpan.org/src/STEVAN/Algorithm-C3-0.01/lib/Algorithm/C3.pm | |
229 | (later versions go about it differently than this code for speed reasons) | |
230 | */ | |
8638e433 | 231 | |
e1a479c5 BB |
232 | if(isa && AvFILLp(isa) >= 0) { |
233 | SV** seqs_ptr; | |
234 | I32 seqs_items; | |
1e05feb3 AL |
235 | HV* const tails = (HV*)sv_2mortal((SV*)newHV()); |
236 | AV* const seqs = (AV*)sv_2mortal((SV*)newAV()); | |
8638e433 RGS |
237 | I32* heads; |
238 | ||
239 | /* This builds @seqs, which is an array of arrays. | |
240 | The members of @seqs are the MROs of | |
241 | the members of @ISA, followed by @ISA itself. | |
242 | */ | |
e1a479c5 BB |
243 | I32 items = AvFILLp(isa) + 1; |
244 | SV** isa_ptr = AvARRAY(isa); | |
245 | while(items--) { | |
1e05feb3 AL |
246 | SV* const isa_item = *isa_ptr++; |
247 | HV* const isa_item_stash = gv_stashsv(isa_item, 0); | |
e1a479c5 | 248 | if(!isa_item_stash) { |
8638e433 RGS |
249 | /* if no stash, make a temporary fake MRO |
250 | containing just itself */ | |
70cd14a1 | 251 | AV* const isa_lin = newAV(); |
e1a479c5 | 252 | av_push(isa_lin, newSVsv(isa_item)); |
70cd14a1 | 253 | av_push(seqs, (SV*)isa_lin); |
e1a479c5 BB |
254 | } |
255 | else { | |
70cd14a1 CB |
256 | /* recursion */ |
257 | AV* const isa_lin = mro_get_linear_isa_c3(isa_item_stash, level + 1); | |
258 | av_push(seqs, SvREFCNT_inc_simple_NN((SV*)isa_lin)); | |
e1a479c5 | 259 | } |
e1a479c5 | 260 | } |
1dcae283 | 261 | av_push(seqs, SvREFCNT_inc_simple_NN((SV*)isa)); |
8638e433 RGS |
262 | |
263 | /* This builds "heads", which as an array of integer array | |
264 | indices, one per seq, which point at the virtual "head" | |
265 | of the seq (initially zero) */ | |
266 | Newxz(heads, AvFILLp(seqs)+1, I32); | |
267 | ||
268 | /* This builds %tails, which has one key for every class | |
269 | mentioned in the tail of any sequence in @seqs (tail meaning | |
270 | everything after the first class, the "head"). The value | |
271 | is how many times this key appears in the tails of @seqs. | |
272 | */ | |
e1a479c5 BB |
273 | seqs_ptr = AvARRAY(seqs); |
274 | seqs_items = AvFILLp(seqs) + 1; | |
275 | while(seqs_items--) { | |
1e05feb3 | 276 | AV* const seq = (AV*)*seqs_ptr++; |
e1a479c5 BB |
277 | I32 seq_items = AvFILLp(seq); |
278 | if(seq_items > 0) { | |
279 | SV** seq_ptr = AvARRAY(seq) + 1; | |
280 | while(seq_items--) { | |
1e05feb3 AL |
281 | SV* const seqitem = *seq_ptr++; |
282 | HE* const he = hv_fetch_ent(tails, seqitem, 0, 0); | |
e1a479c5 BB |
283 | if(!he) { |
284 | hv_store_ent(tails, seqitem, newSViv(1), 0); | |
285 | } | |
286 | else { | |
1e05feb3 | 287 | SV* const val = HeVAL(he); |
e1a479c5 BB |
288 | sv_inc(val); |
289 | } | |
290 | } | |
291 | } | |
292 | } | |
293 | ||
1dcae283 BB |
294 | /* Initialize retval to build the return value in */ |
295 | retval = newAV(); | |
296 | av_push(retval, newSVpvn(stashname, stashname_len)); /* us first */ | |
297 | ||
8638e433 RGS |
298 | /* This loop won't terminate until we either finish building |
299 | the MRO, or get an exception. */ | |
e1a479c5 | 300 | while(1) { |
e1a479c5 BB |
301 | SV* cand = NULL; |
302 | SV* winner = NULL; | |
8638e433 RGS |
303 | int s; |
304 | ||
305 | /* "foreach $seq (@seqs)" */ | |
1e05feb3 | 306 | SV** const avptr = AvARRAY(seqs); |
8638e433 | 307 | for(s = 0; s <= AvFILLp(seqs); s++) { |
e1a479c5 | 308 | SV** svp; |
1e05feb3 AL |
309 | AV * const seq = (AV*)(avptr[s]); |
310 | SV* seqhead; | |
8638e433 RGS |
311 | if(!seq) continue; /* skip empty seqs */ |
312 | svp = av_fetch(seq, heads[s], 0); | |
313 | seqhead = *svp; /* seqhead = head of this seq */ | |
e1a479c5 | 314 | if(!winner) { |
1e05feb3 AL |
315 | HE* tail_entry; |
316 | SV* val; | |
8638e433 RGS |
317 | /* if we haven't found a winner for this round yet, |
318 | and this seqhead is not in tails (or the count | |
319 | for it in tails has dropped to zero), then this | |
320 | seqhead is our new winner, and is added to the | |
321 | final MRO immediately */ | |
e1a479c5 BB |
322 | cand = seqhead; |
323 | if((tail_entry = hv_fetch_ent(tails, cand, 0, 0)) | |
324 | && (val = HeVAL(tail_entry)) | |
25270bc0 | 325 | && (SvIVX(val) > 0)) |
e1a479c5 BB |
326 | continue; |
327 | winner = newSVsv(cand); | |
328 | av_push(retval, winner); | |
8638e433 RGS |
329 | /* note however that even when we find a winner, |
330 | we continue looping over @seqs to do housekeeping */ | |
e1a479c5 BB |
331 | } |
332 | if(!sv_cmp(seqhead, winner)) { | |
8638e433 RGS |
333 | /* Once we have a winner (including the iteration |
334 | where we first found him), inc the head ptr | |
335 | for any seq which had the winner as a head, | |
336 | NULL out any seq which is now empty, | |
337 | and adjust tails for consistency */ | |
338 | ||
1e05feb3 | 339 | const int new_head = ++heads[s]; |
8638e433 | 340 | if(new_head > AvFILLp(seq)) { |
1dcae283 | 341 | SvREFCNT_dec(avptr[s]); |
8638e433 RGS |
342 | avptr[s] = NULL; |
343 | } | |
344 | else { | |
1e05feb3 AL |
345 | HE* tail_entry; |
346 | SV* val; | |
8638e433 RGS |
347 | /* Because we know this new seqhead used to be |
348 | a tail, we can assume it is in tails and has | |
349 | a positive value, which we need to dec */ | |
350 | svp = av_fetch(seq, new_head, 0); | |
351 | seqhead = *svp; | |
352 | tail_entry = hv_fetch_ent(tails, seqhead, 0, 0); | |
353 | val = HeVAL(tail_entry); | |
354 | sv_dec(val); | |
355 | } | |
e1a479c5 BB |
356 | } |
357 | } | |
8638e433 RGS |
358 | |
359 | /* if we found no candidates, we are done building the MRO. | |
360 | !cand means no seqs have any entries left to check */ | |
361 | if(!cand) { | |
362 | Safefree(heads); | |
363 | break; | |
364 | } | |
365 | ||
366 | /* If we had candidates, but nobody won, then the @ISA | |
367 | hierarchy is not C3-incompatible */ | |
e1a479c5 | 368 | if(!winner) { |
8638e433 | 369 | /* we have to do some cleanup before we croak */ |
8638e433 | 370 | |
e1a479c5 | 371 | SvREFCNT_dec(retval); |
8638e433 RGS |
372 | Safefree(heads); |
373 | ||
e1a479c5 BB |
374 | Perl_croak(aTHX_ "Inconsistent hierarchy during C3 merge of class '%s': " |
375 | "merging failed on parent '%"SVf"'", stashname, SVfARG(cand)); | |
376 | } | |
377 | } | |
378 | } | |
1dcae283 BB |
379 | else { /* @ISA was undefined or empty */ |
380 | /* build a retval containing only ourselves */ | |
381 | retval = newAV(); | |
382 | av_push(retval, newSVpvn(stashname, stashname_len)); | |
383 | } | |
e1a479c5 | 384 | |
1c908217 RGS |
385 | /* we don't want anyone modifying the cache entry but us, |
386 | and we do so by replacing it completely */ | |
e1a479c5 | 387 | SvREADONLY_on(retval); |
1c908217 | 388 | |
e1a479c5 BB |
389 | meta->mro_linear_c3 = retval; |
390 | return retval; | |
391 | } | |
392 | ||
393 | /* | |
394 | =for apidoc mro_get_linear_isa | |
395 | ||
396 | Returns either C<mro_get_linear_isa_c3> or | |
397 | C<mro_get_linear_isa_dfs> for the given stash, | |
398 | dependant upon which MRO is in effect | |
399 | for that stash. The return value is a | |
400 | read-only AV*. | |
401 | ||
1c908217 RGS |
402 | You are responsible for C<SvREFCNT_inc()> on the |
403 | return value if you plan to store it anywhere | |
404 | semi-permanently (otherwise it might be deleted | |
405 | out from under you the next time the cache is | |
406 | invalidated). | |
407 | ||
e1a479c5 BB |
408 | =cut |
409 | */ | |
410 | AV* | |
411 | Perl_mro_get_linear_isa(pTHX_ HV *stash) | |
412 | { | |
413 | struct mro_meta* meta; | |
2c7f4b87 | 414 | |
e1a479c5 | 415 | assert(stash); |
2c7f4b87 BB |
416 | if(!SvOOK(stash)) |
417 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); | |
e1a479c5 BB |
418 | |
419 | meta = HvMROMETA(stash); | |
420 | if(meta->mro_which == MRO_DFS) { | |
421 | return mro_get_linear_isa_dfs(stash, 0); | |
422 | } else if(meta->mro_which == MRO_C3) { | |
423 | return mro_get_linear_isa_c3(stash, 0); | |
424 | } else { | |
14f97ce6 | 425 | Perl_croak(aTHX_ "panic: invalid MRO!"); |
e1a479c5 | 426 | } |
7caa839c | 427 | return NULL; /* NOT REACHED */ |
e1a479c5 BB |
428 | } |
429 | ||
430 | /* | |
431 | =for apidoc mro_isa_changed_in | |
432 | ||
1c908217 | 433 | Takes the necessary steps (cache invalidations, mostly) |
e1a479c5 BB |
434 | when the @ISA of the given package has changed. Invoked |
435 | by the C<setisa> magic, should not need to invoke directly. | |
436 | ||
437 | =cut | |
438 | */ | |
439 | void | |
440 | Perl_mro_isa_changed_in(pTHX_ HV* stash) | |
441 | { | |
442 | dVAR; | |
443 | HV* isarev; | |
444 | AV* linear_mro; | |
445 | HE* iter; | |
446 | SV** svp; | |
447 | I32 items; | |
1e05feb3 | 448 | bool is_universal; |
2c7f4b87 | 449 | struct mro_meta * meta; |
e1a479c5 | 450 | |
1e05feb3 AL |
451 | const char * const stashname = HvNAME_get(stash); |
452 | const STRLEN stashname_len = HvNAMELEN_get(stash); | |
e1a479c5 | 453 | |
2c7f4b87 BB |
454 | if(!stashname) |
455 | Perl_croak(aTHX_ "Can't call mro_isa_changed_in() on anonymous symbol table"); | |
456 | ||
e1a479c5 | 457 | /* wipe out the cached linearizations for this stash */ |
2c7f4b87 | 458 | meta = HvMROMETA(stash); |
e1a479c5 BB |
459 | SvREFCNT_dec((SV*)meta->mro_linear_dfs); |
460 | SvREFCNT_dec((SV*)meta->mro_linear_c3); | |
461 | meta->mro_linear_dfs = NULL; | |
462 | meta->mro_linear_c3 = NULL; | |
463 | ||
70cd14a1 CB |
464 | /* Inc the package generation, since our @ISA changed */ |
465 | meta->pkg_gen++; | |
466 | ||
e1a479c5 BB |
467 | /* Wipe the global method cache if this package |
468 | is UNIVERSAL or one of its parents */ | |
dd69841b BB |
469 | |
470 | svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); | |
471 | isarev = svp ? (HV*)*svp : NULL; | |
472 | ||
473 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) | |
474 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { | |
e1a479c5 | 475 | PL_sub_generation++; |
dd69841b BB |
476 | is_universal = TRUE; |
477 | } | |
1e05feb3 | 478 | else { /* Wipe the local method cache otherwise */ |
dd69841b | 479 | meta->cache_gen++; |
1e05feb3 AL |
480 | is_universal = FALSE; |
481 | } | |
e1a479c5 BB |
482 | |
483 | /* wipe next::method cache too */ | |
484 | if(meta->mro_nextmethod) hv_clear(meta->mro_nextmethod); | |
1e05feb3 | 485 | |
e1a479c5 BB |
486 | /* Iterate the isarev (classes that are our children), |
487 | wiping out their linearization and method caches */ | |
dd69841b | 488 | if(isarev) { |
e1a479c5 BB |
489 | hv_iterinit(isarev); |
490 | while((iter = hv_iternext(isarev))) { | |
1e05feb3 | 491 | SV* const revkey = hv_iterkeysv(iter); |
e1a479c5 | 492 | HV* revstash = gv_stashsv(revkey, 0); |
bc2cbbac BB |
493 | struct mro_meta* revmeta; |
494 | ||
495 | if(!revstash) continue; | |
496 | revmeta = HvMROMETA(revstash); | |
e1a479c5 BB |
497 | SvREFCNT_dec((SV*)revmeta->mro_linear_dfs); |
498 | SvREFCNT_dec((SV*)revmeta->mro_linear_c3); | |
499 | revmeta->mro_linear_dfs = NULL; | |
500 | revmeta->mro_linear_c3 = NULL; | |
dd69841b BB |
501 | if(!is_universal) |
502 | revmeta->cache_gen++; | |
e1a479c5 BB |
503 | if(revmeta->mro_nextmethod) |
504 | hv_clear(revmeta->mro_nextmethod); | |
505 | } | |
506 | } | |
507 | ||
1c908217 RGS |
508 | /* Now iterate our MRO (parents), and do a few things: |
509 | 1) instantiate with the "fake" flag if they don't exist | |
510 | 2) flag them as universal if we are universal | |
511 | 3) Add everything from our isarev to their isarev | |
512 | */ | |
513 | ||
514 | /* We're starting at the 2nd element, skipping ourselves here */ | |
e1a479c5 BB |
515 | linear_mro = mro_get_linear_isa(stash); |
516 | svp = AvARRAY(linear_mro) + 1; | |
517 | items = AvFILLp(linear_mro); | |
1c908217 | 518 | |
e1a479c5 BB |
519 | while (items--) { |
520 | SV* const sv = *svp++; | |
e1a479c5 BB |
521 | HV* mroisarev; |
522 | ||
1e05feb3 | 523 | HE *he = hv_fetch_ent(PL_isarev, sv, 0, 0); |
dd69841b BB |
524 | if(!he) { |
525 | he = hv_store_ent(PL_isarev, sv, (SV*)newHV(), 0); | |
e1a479c5 | 526 | } |
dd69841b | 527 | mroisarev = (HV*)HeVAL(he); |
e1a479c5 | 528 | |
25270bc0 NC |
529 | /* This hash only ever contains PL_sv_yes. Storing it over itself is |
530 | almost as cheap as calling hv_exists, so on aggregate we expect to | |
531 | save time by not making two calls to the common HV code for the | |
532 | case where it doesn't exist. */ | |
533 | ||
dd69841b | 534 | hv_store(mroisarev, stashname, stashname_len, &PL_sv_yes, 0); |
e1a479c5 BB |
535 | |
536 | if(isarev) { | |
537 | hv_iterinit(isarev); | |
538 | while((iter = hv_iternext(isarev))) { | |
dd69841b | 539 | I32 revkeylen; |
1e05feb3 | 540 | char* const revkey = hv_iterkey(iter, &revkeylen); |
dd69841b | 541 | hv_store(mroisarev, revkey, revkeylen, &PL_sv_yes, 0); |
e1a479c5 BB |
542 | } |
543 | } | |
544 | } | |
545 | } | |
546 | ||
547 | /* | |
548 | =for apidoc mro_method_changed_in | |
549 | ||
47c9dd14 BB |
550 | Invalidates method caching on any child classes |
551 | of the given stash, so that they might notice | |
552 | the changes in this one. | |
e1a479c5 BB |
553 | |
554 | Ideally, all instances of C<PL_sub_generation++> in | |
dd69841b BB |
555 | perl source outside of C<mro.c> should be |
556 | replaced by calls to this. | |
557 | ||
558 | Perl automatically handles most of the common | |
559 | ways a method might be redefined. However, there | |
560 | are a few ways you could change a method in a stash | |
561 | without the cache code noticing, in which case you | |
562 | need to call this method afterwards: | |
e1a479c5 | 563 | |
dd69841b BB |
564 | 1) Directly manipulating the stash HV entries from |
565 | XS code. | |
e1a479c5 | 566 | |
dd69841b BB |
567 | 2) Assigning a reference to a readonly scalar |
568 | constant into a stash entry in order to create | |
569 | a constant subroutine (like constant.pm | |
570 | does). | |
571 | ||
572 | This same method is available from pure perl | |
573 | via, C<mro::method_changed_in(classname)>. | |
e1a479c5 BB |
574 | |
575 | =cut | |
576 | */ | |
577 | void | |
578 | Perl_mro_method_changed_in(pTHX_ HV *stash) | |
579 | { | |
1e05feb3 AL |
580 | const char * const stashname = HvNAME_get(stash); |
581 | const STRLEN stashname_len = HvNAMELEN_get(stash); | |
dd69841b | 582 | |
1e05feb3 AL |
583 | SV ** const svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); |
584 | HV * const isarev = svp ? (HV*)*svp : NULL; | |
e1a479c5 | 585 | |
2c7f4b87 BB |
586 | if(!stashname) |
587 | Perl_croak(aTHX_ "Can't call mro_method_changed_in() on anonymous symbol table"); | |
588 | ||
70cd14a1 CB |
589 | /* Inc the package generation, since a local method changed */ |
590 | HvMROMETA(stash)->pkg_gen++; | |
591 | ||
e1a479c5 BB |
592 | /* If stash is UNIVERSAL, or one of UNIVERSAL's parents, |
593 | invalidate all method caches globally */ | |
dd69841b BB |
594 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) |
595 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { | |
e1a479c5 BB |
596 | PL_sub_generation++; |
597 | return; | |
598 | } | |
599 | ||
600 | /* else, invalidate the method caches of all child classes, | |
601 | but not itself */ | |
dd69841b | 602 | if(isarev) { |
1e05feb3 AL |
603 | HE* iter; |
604 | ||
e1a479c5 BB |
605 | hv_iterinit(isarev); |
606 | while((iter = hv_iternext(isarev))) { | |
1e05feb3 AL |
607 | SV* const revkey = hv_iterkeysv(iter); |
608 | HV* const revstash = gv_stashsv(revkey, 0); | |
bc2cbbac BB |
609 | struct mro_meta* mrometa; |
610 | ||
611 | if(!revstash) continue; | |
612 | mrometa = HvMROMETA(revstash); | |
dd69841b | 613 | mrometa->cache_gen++; |
e1a479c5 BB |
614 | if(mrometa->mro_nextmethod) |
615 | hv_clear(mrometa->mro_nextmethod); | |
616 | } | |
617 | } | |
618 | } | |
619 | ||
620 | /* These two are static helpers for next::method and friends, | |
621 | and re-implement a bunch of the code from pp_caller() in | |
622 | a more efficient manner for this particular usage. | |
623 | */ | |
624 | ||
625 | STATIC I32 | |
626 | __dopoptosub_at(const PERL_CONTEXT *cxstk, I32 startingblock) { | |
627 | I32 i; | |
628 | for (i = startingblock; i >= 0; i--) { | |
629 | if(CxTYPE((PERL_CONTEXT*)(&cxstk[i])) == CXt_SUB) return i; | |
630 | } | |
631 | return i; | |
632 | } | |
633 | ||
e1a479c5 BB |
634 | #include "XSUB.h" |
635 | ||
636 | XS(XS_mro_get_linear_isa); | |
637 | XS(XS_mro_set_mro); | |
638 | XS(XS_mro_get_mro); | |
639 | XS(XS_mro_get_isarev); | |
640 | XS(XS_mro_is_universal); | |
c5860d66 | 641 | XS(XS_mro_invalidate_method_caches); |
e1a479c5 | 642 | XS(XS_mro_method_changed_in); |
70cd14a1 | 643 | XS(XS_mro_get_pkg_gen); |
f58cd386 | 644 | XS(XS_mro_nextcan); |
e1a479c5 BB |
645 | |
646 | void | |
647 | Perl_boot_core_mro(pTHX) | |
648 | { | |
649 | dVAR; | |
650 | static const char file[] = __FILE__; | |
651 | ||
652 | newXSproto("mro::get_linear_isa", XS_mro_get_linear_isa, file, "$;$"); | |
653 | newXSproto("mro::set_mro", XS_mro_set_mro, file, "$$"); | |
654 | newXSproto("mro::get_mro", XS_mro_get_mro, file, "$"); | |
655 | newXSproto("mro::get_isarev", XS_mro_get_isarev, file, "$"); | |
656 | newXSproto("mro::is_universal", XS_mro_is_universal, file, "$"); | |
c5860d66 | 657 | newXSproto("mro::invalidate_all_method_caches", XS_mro_invalidate_method_caches, file, ""); |
e1a479c5 | 658 | newXSproto("mro::method_changed_in", XS_mro_method_changed_in, file, "$"); |
70cd14a1 | 659 | newXSproto("mro::get_pkg_gen", XS_mro_get_pkg_gen, file, "$"); |
f58cd386 | 660 | newXS("mro::_nextcan", XS_mro_nextcan, file); |
e1a479c5 BB |
661 | } |
662 | ||
663 | XS(XS_mro_get_linear_isa) { | |
664 | dVAR; | |
665 | dXSARGS; | |
666 | AV* RETVAL; | |
667 | HV* class_stash; | |
668 | SV* classname; | |
669 | ||
670 | PERL_UNUSED_ARG(cv); | |
671 | ||
672 | if(items < 1 || items > 2) | |
673 | Perl_croak(aTHX_ "Usage: mro::get_linear_isa(classname [, type ])"); | |
674 | ||
675 | classname = ST(0); | |
676 | class_stash = gv_stashsv(classname, 0); | |
e1a479c5 | 677 | |
70cd14a1 CB |
678 | if(!class_stash) { |
679 | /* No stash exists yet, give them just the classname */ | |
680 | AV* isalin = newAV(); | |
681 | av_push(isalin, newSVsv(classname)); | |
682 | ST(0) = sv_2mortal(newRV_noinc((SV*)isalin)); | |
683 | XSRETURN(1); | |
684 | } | |
685 | else if(items > 1) { | |
1e05feb3 | 686 | const char* const which = SvPV_nolen(ST(1)); |
e1a479c5 BB |
687 | if(strEQ(which, "dfs")) |
688 | RETVAL = mro_get_linear_isa_dfs(class_stash, 0); | |
689 | else if(strEQ(which, "c3")) | |
690 | RETVAL = mro_get_linear_isa_c3(class_stash, 0); | |
691 | else | |
692 | Perl_croak(aTHX_ "Invalid mro name: '%s'", which); | |
693 | } | |
694 | else { | |
695 | RETVAL = mro_get_linear_isa(class_stash); | |
696 | } | |
697 | ||
698 | ST(0) = newRV_inc((SV*)RETVAL); | |
699 | sv_2mortal(ST(0)); | |
700 | XSRETURN(1); | |
701 | } | |
702 | ||
703 | XS(XS_mro_set_mro) | |
704 | { | |
705 | dVAR; | |
706 | dXSARGS; | |
707 | SV* classname; | |
708 | char* whichstr; | |
709 | mro_alg which; | |
710 | HV* class_stash; | |
711 | struct mro_meta* meta; | |
712 | ||
713 | PERL_UNUSED_ARG(cv); | |
714 | ||
715 | if (items != 2) | |
716 | Perl_croak(aTHX_ "Usage: mro::set_mro(classname, type)"); | |
717 | ||
718 | classname = ST(0); | |
719 | whichstr = SvPV_nolen(ST(1)); | |
720 | class_stash = gv_stashsv(classname, GV_ADD); | |
721 | if(!class_stash) Perl_croak(aTHX_ "Cannot create class: '%"SVf"'!", SVfARG(classname)); | |
722 | meta = HvMROMETA(class_stash); | |
723 | ||
724 | if(strEQ(whichstr, "dfs")) | |
725 | which = MRO_DFS; | |
726 | else if(strEQ(whichstr, "c3")) | |
727 | which = MRO_C3; | |
728 | else | |
729 | Perl_croak(aTHX_ "Invalid mro name: '%s'", whichstr); | |
730 | ||
731 | if(meta->mro_which != which) { | |
732 | meta->mro_which = which; | |
733 | /* Only affects local method cache, not | |
734 | even child classes */ | |
dd69841b | 735 | meta->cache_gen++; |
e1a479c5 BB |
736 | if(meta->mro_nextmethod) |
737 | hv_clear(meta->mro_nextmethod); | |
738 | } | |
739 | ||
740 | XSRETURN_EMPTY; | |
741 | } | |
742 | ||
743 | ||
744 | XS(XS_mro_get_mro) | |
745 | { | |
746 | dVAR; | |
747 | dXSARGS; | |
748 | SV* classname; | |
749 | HV* class_stash; | |
e1a479c5 BB |
750 | |
751 | PERL_UNUSED_ARG(cv); | |
752 | ||
753 | if (items != 1) | |
754 | Perl_croak(aTHX_ "Usage: mro::get_mro(classname)"); | |
755 | ||
756 | classname = ST(0); | |
757 | class_stash = gv_stashsv(classname, 0); | |
e1a479c5 | 758 | |
70cd14a1 | 759 | if(!class_stash || HvMROMETA(class_stash)->mro_which == MRO_DFS) |
e1a479c5 BB |
760 | ST(0) = sv_2mortal(newSVpvn("dfs", 3)); |
761 | else | |
762 | ST(0) = sv_2mortal(newSVpvn("c3", 2)); | |
763 | ||
764 | XSRETURN(1); | |
765 | } | |
766 | ||
767 | XS(XS_mro_get_isarev) | |
768 | { | |
769 | dVAR; | |
770 | dXSARGS; | |
771 | SV* classname; | |
dd69841b | 772 | SV** svp; |
e1a479c5 | 773 | HV* isarev; |
70cd14a1 CB |
774 | char* classname_pv; |
775 | STRLEN classname_len; | |
776 | AV* ret_array; | |
e1a479c5 BB |
777 | |
778 | PERL_UNUSED_ARG(cv); | |
779 | ||
780 | if (items != 1) | |
781 | Perl_croak(aTHX_ "Usage: mro::get_isarev(classname)"); | |
782 | ||
783 | classname = ST(0); | |
784 | ||
e1a479c5 | 785 | SP -= items; |
dd69841b | 786 | |
70cd14a1 CB |
787 | |
788 | classname_pv = SvPV_nolen(classname); | |
789 | classname_len = strlen(classname_pv); | |
790 | svp = hv_fetch(PL_isarev, classname_pv, classname_len, 0); | |
dd69841b | 791 | isarev = svp ? (HV*)*svp : NULL; |
70cd14a1 CB |
792 | |
793 | ret_array = newAV(); | |
dd69841b | 794 | if(isarev) { |
e1a479c5 BB |
795 | HE* iter; |
796 | hv_iterinit(isarev); | |
797 | while((iter = hv_iternext(isarev))) | |
70cd14a1 | 798 | av_push(ret_array, newSVsv(hv_iterkeysv(iter))); |
e1a479c5 | 799 | } |
70cd14a1 | 800 | XPUSHs(sv_2mortal(newRV_noinc((SV*)ret_array))); |
e1a479c5 BB |
801 | |
802 | PUTBACK; | |
803 | return; | |
804 | } | |
805 | ||
806 | XS(XS_mro_is_universal) | |
807 | { | |
808 | dVAR; | |
809 | dXSARGS; | |
810 | SV* classname; | |
dd69841b | 811 | HV* isarev; |
70cd14a1 CB |
812 | char* classname_pv; |
813 | STRLEN classname_len; | |
dd69841b | 814 | SV** svp; |
e1a479c5 BB |
815 | |
816 | PERL_UNUSED_ARG(cv); | |
817 | ||
818 | if (items != 1) | |
dd69841b | 819 | Perl_croak(aTHX_ "Usage: mro::is_universal(classname)"); |
e1a479c5 BB |
820 | |
821 | classname = ST(0); | |
e1a479c5 | 822 | |
70cd14a1 CB |
823 | classname_pv = SvPV_nolen(classname); |
824 | classname_len = strlen(classname_pv); | |
dd69841b | 825 | |
70cd14a1 | 826 | svp = hv_fetch(PL_isarev, classname_pv, classname_len, 0); |
dd69841b BB |
827 | isarev = svp ? (HV*)*svp : NULL; |
828 | ||
70cd14a1 | 829 | if((classname_len == 9 && strEQ(classname_pv, "UNIVERSAL")) |
dd69841b | 830 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) |
9edc5bb8 RGS |
831 | XSRETURN_YES; |
832 | else | |
833 | XSRETURN_NO; | |
e1a479c5 BB |
834 | } |
835 | ||
c5860d66 | 836 | XS(XS_mro_invalidate_method_caches) |
e1a479c5 BB |
837 | { |
838 | dVAR; | |
839 | dXSARGS; | |
840 | ||
841 | PERL_UNUSED_ARG(cv); | |
842 | ||
843 | if (items != 0) | |
844 | Perl_croak(aTHX_ "Usage: mro::invalidate_all_method_caches()"); | |
845 | ||
846 | PL_sub_generation++; | |
847 | ||
848 | XSRETURN_EMPTY; | |
849 | } | |
850 | ||
e1a479c5 BB |
851 | XS(XS_mro_method_changed_in) |
852 | { | |
853 | dVAR; | |
854 | dXSARGS; | |
855 | SV* classname; | |
856 | HV* class_stash; | |
857 | ||
858 | PERL_UNUSED_ARG(cv); | |
859 | ||
860 | if(items != 1) | |
861 | Perl_croak(aTHX_ "Usage: mro::method_changed_in(classname)"); | |
862 | ||
863 | classname = ST(0); | |
864 | ||
865 | class_stash = gv_stashsv(classname, 0); | |
866 | if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); | |
867 | ||
868 | mro_method_changed_in(class_stash); | |
869 | ||
870 | XSRETURN_EMPTY; | |
871 | } | |
872 | ||
70cd14a1 CB |
873 | XS(XS_mro_get_pkg_gen) |
874 | { | |
875 | dVAR; | |
876 | dXSARGS; | |
877 | SV* classname; | |
878 | HV* class_stash; | |
879 | ||
880 | PERL_UNUSED_ARG(cv); | |
881 | ||
882 | if(items != 1) | |
883 | Perl_croak(aTHX_ "Usage: mro::get_pkg_gen(classname)"); | |
884 | ||
885 | classname = ST(0); | |
886 | ||
887 | class_stash = gv_stashsv(classname, 0); | |
888 | ||
889 | SP -= items; | |
890 | ||
891 | XPUSHs(sv_2mortal(newSViv( | |
892 | class_stash ? HvMROMETA(class_stash)->pkg_gen : 0 | |
893 | ))); | |
894 | ||
895 | PUTBACK; | |
896 | return; | |
897 | } | |
898 | ||
f58cd386 | 899 | XS(XS_mro_nextcan) |
e1a479c5 BB |
900 | { |
901 | dVAR; | |
902 | dXSARGS; | |
f58cd386 BB |
903 | SV* self = ST(0); |
904 | const I32 throw_nomethod = SvIVX(ST(1)); | |
bbd28cb9 | 905 | register I32 cxix = cxstack_ix; |
f58cd386 BB |
906 | register const PERL_CONTEXT *ccstack = cxstack; |
907 | const PERL_SI *top_si = PL_curstackinfo; | |
908 | HV* selfstash; | |
909 | SV *stashname; | |
910 | const char *fq_subname; | |
911 | const char *subname; | |
912 | STRLEN stashname_len; | |
913 | STRLEN subname_len; | |
914 | SV* sv; | |
915 | GV** gvp; | |
916 | AV* linear_av; | |
917 | SV** linear_svp; | |
918 | const char *hvname; | |
919 | I32 entries; | |
920 | struct mro_meta* selfmeta; | |
921 | HV* nmcache; | |
bbd28cb9 | 922 | I32 i; |
e1a479c5 | 923 | |
48fc4736 JH |
924 | PERL_UNUSED_ARG(cv); |
925 | ||
f58cd386 BB |
926 | SP -= items; |
927 | ||
928 | if(sv_isobject(self)) | |
929 | selfstash = SvSTASH(SvRV(self)); | |
930 | else | |
931 | selfstash = gv_stashsv(self, 0); | |
932 | ||
933 | assert(selfstash); | |
934 | ||
935 | hvname = HvNAME_get(selfstash); | |
936 | if (!hvname) | |
937 | Perl_croak(aTHX_ "Can't use anonymous symbol table for method lookup"); | |
938 | ||
f58cd386 BB |
939 | /* This block finds the contextually-enclosing fully-qualified subname, |
940 | much like looking at (caller($i))[3] until you find a real sub that | |
bbd28cb9 BB |
941 | isn't ANON, etc (also skips over pureperl next::method, etc) */ |
942 | for(i = 0; i < 2; i++) { | |
943 | cxix = __dopoptosub_at(ccstack, cxix); | |
944 | for (;;) { | |
945 | GV* cvgv; | |
946 | STRLEN fq_subname_len; | |
947 | ||
948 | /* we may be in a higher stacklevel, so dig down deeper */ | |
949 | while (cxix < 0) { | |
950 | if(top_si->si_type == PERLSI_MAIN) | |
951 | Perl_croak(aTHX_ "next::method/next::can/maybe::next::method must be used in method context"); | |
952 | top_si = top_si->si_prev; | |
953 | ccstack = top_si->si_cxstack; | |
954 | cxix = __dopoptosub_at(ccstack, top_si->si_cxix); | |
955 | } | |
f58cd386 | 956 | |
bbd28cb9 BB |
957 | if(CxTYPE((PERL_CONTEXT*)(&ccstack[cxix])) != CXt_SUB |
958 | || (PL_DBsub && GvCV(PL_DBsub) && ccstack[cxix].blk_sub.cv == GvCV(PL_DBsub))) { | |
959 | cxix = __dopoptosub_at(ccstack, cxix - 1); | |
960 | continue; | |
961 | } | |
e1a479c5 | 962 | |
bbd28cb9 BB |
963 | { |
964 | const I32 dbcxix = __dopoptosub_at(ccstack, cxix - 1); | |
965 | if (PL_DBsub && GvCV(PL_DBsub) && dbcxix >= 0 && ccstack[dbcxix].blk_sub.cv == GvCV(PL_DBsub)) { | |
966 | if(CxTYPE((PERL_CONTEXT*)(&ccstack[dbcxix])) != CXt_SUB) { | |
967 | cxix = dbcxix; | |
968 | continue; | |
969 | } | |
f58cd386 BB |
970 | } |
971 | } | |
f58cd386 | 972 | |
bbd28cb9 | 973 | cvgv = CvGV(ccstack[cxix].blk_sub.cv); |
f58cd386 | 974 | |
bbd28cb9 BB |
975 | if(!isGV(cvgv)) { |
976 | cxix = __dopoptosub_at(ccstack, cxix - 1); | |
977 | continue; | |
978 | } | |
f58cd386 | 979 | |
bbd28cb9 BB |
980 | /* we found a real sub here */ |
981 | sv = sv_2mortal(newSV(0)); | |
f58cd386 | 982 | |
bbd28cb9 | 983 | gv_efullname3(sv, cvgv, NULL); |
f58cd386 | 984 | |
bbd28cb9 BB |
985 | fq_subname = SvPVX(sv); |
986 | fq_subname_len = SvCUR(sv); | |
f58cd386 | 987 | |
bbd28cb9 BB |
988 | subname = strrchr(fq_subname, ':'); |
989 | if(!subname) | |
990 | Perl_croak(aTHX_ "next::method/next::can/maybe::next::method cannot find enclosing method"); | |
f58cd386 | 991 | |
bbd28cb9 BB |
992 | subname++; |
993 | subname_len = fq_subname_len - (subname - fq_subname); | |
994 | if(subname_len == 8 && strEQ(subname, "__ANON__")) { | |
995 | cxix = __dopoptosub_at(ccstack, cxix - 1); | |
996 | continue; | |
997 | } | |
998 | break; | |
f58cd386 | 999 | } |
bbd28cb9 | 1000 | cxix--; |
e1a479c5 | 1001 | } |
f58cd386 BB |
1002 | |
1003 | /* If we made it to here, we found our context */ | |
1004 | ||
1005 | /* Initialize the next::method cache for this stash | |
1006 | if necessary */ | |
1007 | selfmeta = HvMROMETA(selfstash); | |
1008 | if(!(nmcache = selfmeta->mro_nextmethod)) { | |
1009 | nmcache = selfmeta->mro_nextmethod = newHV(); | |
1010 | } | |
1011 | else { /* Use the cached coderef if it exists */ | |
1012 | HE* cache_entry = hv_fetch_ent(nmcache, sv, 0, 0); | |
1013 | if (cache_entry) { | |
1014 | SV* const val = HeVAL(cache_entry); | |
1015 | if(val == &PL_sv_undef) { | |
1016 | if(throw_nomethod) | |
1017 | Perl_croak(aTHX_ "No next::method '%s' found for %s", subname, hvname); | |
1018 | XSRETURN_EMPTY; | |
1019 | } | |
1020 | XPUSHs(sv_2mortal(newRV_inc(val))); | |
1021 | XSRETURN(1); | |
1022 | } | |
e1a479c5 BB |
1023 | } |
1024 | ||
f58cd386 | 1025 | /* beyond here is just for cache misses, so perf isn't as critical */ |
e1a479c5 | 1026 | |
f58cd386 BB |
1027 | stashname_len = subname - fq_subname - 2; |
1028 | stashname = sv_2mortal(newSVpvn(fq_subname, stashname_len)); | |
e1a479c5 | 1029 | |
f58cd386 | 1030 | linear_av = mro_get_linear_isa_c3(selfstash, 0); /* has ourselves at the top of the list */ |
e1a479c5 | 1031 | |
f58cd386 BB |
1032 | linear_svp = AvARRAY(linear_av); |
1033 | entries = AvFILLp(linear_av) + 1; | |
e1a479c5 | 1034 | |
f58cd386 BB |
1035 | /* Walk down our MRO, skipping everything up |
1036 | to the contextually enclosing class */ | |
1037 | while (entries--) { | |
1038 | SV * const linear_sv = *linear_svp++; | |
1039 | assert(linear_sv); | |
1040 | if(sv_eq(linear_sv, stashname)) | |
1041 | break; | |
1042 | } | |
e1a479c5 | 1043 | |
f58cd386 BB |
1044 | /* Now search the remainder of the MRO for the |
1045 | same method name as the contextually enclosing | |
1046 | method */ | |
1047 | if(entries > 0) { | |
1048 | while (entries--) { | |
1049 | SV * const linear_sv = *linear_svp++; | |
1050 | HV* curstash; | |
1051 | GV* candidate; | |
1052 | CV* cand_cv; | |
e1a479c5 | 1053 | |
f58cd386 BB |
1054 | assert(linear_sv); |
1055 | curstash = gv_stashsv(linear_sv, FALSE); | |
1056 | ||
1057 | if (!curstash) { | |
1058 | if (ckWARN(WARN_SYNTAX)) | |
1059 | Perl_warner(aTHX_ packWARN(WARN_SYNTAX), "Can't locate package %"SVf" for @%s::ISA", | |
1060 | (void*)linear_sv, hvname); | |
1061 | continue; | |
1062 | } | |
1063 | ||
1064 | assert(curstash); | |
1065 | ||
1066 | gvp = (GV**)hv_fetch(curstash, subname, subname_len, 0); | |
1067 | if (!gvp) continue; | |
1068 | ||
1069 | candidate = *gvp; | |
1070 | assert(candidate); | |
1071 | ||
1072 | if (SvTYPE(candidate) != SVt_PVGV) | |
1073 | gv_init(candidate, curstash, subname, subname_len, TRUE); | |
1074 | ||
1075 | /* Notably, we only look for real entries, not method cache | |
1076 | entries, because in C3 the method cache of a parent is not | |
1077 | valid for the child */ | |
1078 | if (SvTYPE(candidate) == SVt_PVGV && (cand_cv = GvCV(candidate)) && !GvCVGEN(candidate)) { | |
1079 | SvREFCNT_inc_simple_void_NN((SV*)cand_cv); | |
1080 | hv_store_ent(nmcache, newSVsv(sv), (SV*)cand_cv, 0); | |
1081 | XPUSHs(sv_2mortal(newRV_inc((SV*)cand_cv))); | |
1082 | XSRETURN(1); | |
1083 | } | |
1084 | } | |
e1a479c5 BB |
1085 | } |
1086 | ||
f58cd386 BB |
1087 | hv_store_ent(nmcache, newSVsv(sv), &PL_sv_undef, 0); |
1088 | if(throw_nomethod) | |
1089 | Perl_croak(aTHX_ "No next::method '%s' found for %s", subname, hvname); | |
1090 | XSRETURN_EMPTY; | |
e1a479c5 BB |
1091 | } |
1092 | ||
1093 | /* | |
1094 | * Local variables: | |
1095 | * c-indentation-style: bsd | |
1096 | * c-basic-offset: 4 | |
1097 | * indent-tabs-mode: t | |
1098 | * End: | |
1099 | * | |
1100 | * ex: set ts=8 sts=4 sw=4 noet: | |
1101 | */ |