Commit | Line | Data |
e1a479c5 |
1 | /* mro.c |
2 | * |
3 | * Copyright (c) 2007 Brandon L Black |
1129b882 |
4 | * Copyright (c) 2007, 2008 Larry Wall and others |
e1a479c5 |
5 | * |
6 | * You may distribute under the terms of either the GNU General Public |
7 | * License or the Artistic License, as specified in the README file. |
8 | * |
9 | */ |
10 | |
11 | /* |
4ac71550 |
12 | * 'Which order shall we go in?' said Frodo. 'Eldest first, or quickest first? |
13 | * You'll be last either way, Master Peregrin.' |
14 | * |
15 | * [p.101 of _The Lord of the Rings_, I/iii: "A Conspiracy Unmasked"] |
cac98860 |
16 | */ |
17 | |
18 | /* |
e1a479c5 |
19 | =head1 MRO Functions |
20 | |
21 | These functions are related to the method resolution order of perl classes |
22 | |
23 | =cut |
24 | */ |
25 | |
26 | #include "EXTERN.h" |
4befac30 |
27 | #define PERL_IN_MRO_C |
e1a479c5 |
28 | #include "perl.h" |
29 | |
a3e6e81e |
30 | static const struct mro_alg dfs_alg = |
31 | {S_mro_get_linear_isa_dfs, "dfs", 3, 0, 0}; |
3d76853f |
32 | |
fa60396f |
33 | SV * |
34 | Perl_mro_get_private_data(pTHX_ struct mro_meta *const smeta, |
35 | const struct mro_alg *const which) |
36 | { |
37 | SV **data; |
38 | PERL_ARGS_ASSERT_MRO_GET_PRIVATE_DATA; |
39 | |
5844ac76 |
40 | data = (SV **)Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL, |
41 | which->name, which->length, which->kflags, |
42 | HV_FETCH_JUST_SV, NULL, which->hash); |
fa60396f |
43 | if (!data) |
44 | return NULL; |
45 | |
46 | /* If we've been asked to look up the private data for the current MRO, then |
47 | cache it. */ |
48 | if (smeta->mro_which == which) |
3a6fa573 |
49 | smeta->mro_linear_current = *data; |
fa60396f |
50 | |
51 | return *data; |
52 | } |
53 | |
54 | SV * |
55 | Perl_mro_set_private_data(pTHX_ struct mro_meta *const smeta, |
56 | const struct mro_alg *const which, SV *const data) |
57 | { |
58 | PERL_ARGS_ASSERT_MRO_SET_PRIVATE_DATA; |
59 | |
9953ff72 |
60 | if (!smeta->mro_linear_all) { |
553e831a |
61 | if (smeta->mro_which == which) { |
62 | /* If all we need to store is the current MRO's data, then don't use |
63 | memory on a hash with 1 element - store it direct, and signal |
64 | this by leaving the would-be-hash NULL. */ |
3a6fa573 |
65 | smeta->mro_linear_current = data; |
553e831a |
66 | return data; |
67 | } else { |
68 | HV *const hv = newHV(); |
69 | /* Start with 2 buckets. It's unlikely we'll need more. */ |
70 | HvMAX(hv) = 1; |
9953ff72 |
71 | smeta->mro_linear_all = hv; |
553e831a |
72 | |
3a6fa573 |
73 | if (smeta->mro_linear_current) { |
553e831a |
74 | /* If we were storing something directly, put it in the hash |
75 | before we lose it. */ |
76 | Perl_mro_set_private_data(aTHX_ smeta, smeta->mro_which, |
3a6fa573 |
77 | smeta->mro_linear_current); |
553e831a |
78 | } |
79 | } |
80 | } |
81 | |
82 | /* We get here if we're storing more than one linearisation for this stash, |
83 | or the linearisation we are storing is not that if its current MRO. */ |
84 | |
85 | if (smeta->mro_which == which) { |
86 | /* If we've been asked to store the private data for the current MRO, |
87 | then cache it. */ |
3a6fa573 |
88 | smeta->mro_linear_current = data; |
fa60396f |
89 | } |
90 | |
9953ff72 |
91 | if (!Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL, |
fa60396f |
92 | which->name, which->length, which->kflags, |
93 | HV_FETCH_ISSTORE, data, which->hash)) { |
94 | Perl_croak(aTHX_ "panic: hv_store() failed in set_mro_private_data() " |
95 | "for '%.*s' %d", (int) which->length, which->name, |
96 | which->kflags); |
97 | } |
98 | |
99 | return data; |
100 | } |
101 | |
a3e6e81e |
102 | const struct mro_alg * |
103 | Perl_mro_get_from_name(pTHX_ SV *name) { |
104 | SV **data; |
105 | |
106 | PERL_ARGS_ASSERT_MRO_GET_FROM_NAME; |
107 | |
5844ac76 |
108 | data = (SV **)Perl_hv_common(aTHX_ PL_registered_mros, name, NULL, 0, 0, |
109 | HV_FETCH_JUST_SV, NULL, 0); |
a3e6e81e |
110 | if (!data) |
111 | return NULL; |
112 | assert(SvTYPE(*data) == SVt_IV); |
113 | assert(SvIOK(*data)); |
114 | return INT2PTR(const struct mro_alg *, SvUVX(*data)); |
115 | } |
116 | |
117 | void |
118 | Perl_mro_register(pTHX_ const struct mro_alg *mro) { |
119 | SV *wrapper = newSVuv(PTR2UV(mro)); |
120 | |
121 | PERL_ARGS_ASSERT_MRO_REGISTER; |
122 | |
123 | |
124 | if (!Perl_hv_common(aTHX_ PL_registered_mros, NULL, |
125 | mro->name, mro->length, mro->kflags, |
126 | HV_FETCH_ISSTORE, wrapper, mro->hash)) { |
127 | SvREFCNT_dec(wrapper); |
128 | Perl_croak(aTHX_ "panic: hv_store() failed in mro_register() " |
129 | "for '%.*s' %d", (int) mro->length, mro->name, mro->kflags); |
3d76853f |
130 | } |
3d76853f |
131 | } |
132 | |
e1a479c5 |
133 | struct mro_meta* |
134 | Perl_mro_meta_init(pTHX_ HV* stash) |
135 | { |
9fe4aecf |
136 | struct mro_meta* newmeta; |
e1a479c5 |
137 | |
7918f24d |
138 | PERL_ARGS_ASSERT_MRO_META_INIT; |
e1a479c5 |
139 | assert(HvAUX(stash)); |
140 | assert(!(HvAUX(stash)->xhv_mro_meta)); |
183086be |
141 | Newxz(newmeta, 1, struct mro_meta); |
9fe4aecf |
142 | HvAUX(stash)->xhv_mro_meta = newmeta; |
dd69841b |
143 | newmeta->cache_gen = 1; |
70cd14a1 |
144 | newmeta->pkg_gen = 1; |
a3e6e81e |
145 | newmeta->mro_which = &dfs_alg; |
e1a479c5 |
146 | |
147 | return newmeta; |
148 | } |
149 | |
150 | #if defined(USE_ITHREADS) |
151 | |
152 | /* for sv_dup on new threads */ |
153 | struct mro_meta* |
154 | Perl_mro_meta_dup(pTHX_ struct mro_meta* smeta, CLONE_PARAMS* param) |
155 | { |
e1a479c5 |
156 | struct mro_meta* newmeta; |
157 | |
7918f24d |
158 | PERL_ARGS_ASSERT_MRO_META_DUP; |
e1a479c5 |
159 | |
33e12d9d |
160 | Newx(newmeta, 1, struct mro_meta); |
161 | Copy(smeta, newmeta, 1, struct mro_meta); |
162 | |
9953ff72 |
163 | if (newmeta->mro_linear_all) { |
164 | newmeta->mro_linear_all |
165 | = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_linear_all, param))); |
553e831a |
166 | /* This is just acting as a shortcut pointer, and will be automatically |
167 | updated on the first get. */ |
3a6fa573 |
168 | newmeta->mro_linear_current = NULL; |
169 | } else if (newmeta->mro_linear_current) { |
553e831a |
170 | /* Only the current MRO is stored, so this owns the data. */ |
3a6fa573 |
171 | newmeta->mro_linear_current |
172 | = SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_linear_current, |
173 | param)); |
553e831a |
174 | } |
175 | |
33e12d9d |
176 | if (newmeta->mro_nextmethod) |
177 | newmeta->mro_nextmethod |
ad64d0ec |
178 | = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->mro_nextmethod, param))); |
a49ba3fc |
179 | if (newmeta->isa) |
180 | newmeta->isa |
ad64d0ec |
181 | = MUTABLE_HV(SvREFCNT_inc(sv_dup((const SV *)newmeta->isa, param))); |
e1a479c5 |
182 | |
183 | return newmeta; |
184 | } |
185 | |
186 | #endif /* USE_ITHREADS */ |
187 | |
a49ba3fc |
188 | HV * |
189 | Perl_get_isa_hash(pTHX_ HV *const stash) |
190 | { |
191 | dVAR; |
192 | struct mro_meta *const meta = HvMROMETA(stash); |
193 | |
194 | PERL_ARGS_ASSERT_GET_ISA_HASH; |
195 | |
6e4aef59 |
196 | if (!meta->isa) { |
197 | AV *const isa = mro_get_linear_isa(stash); |
198 | if (!meta->isa) { |
199 | HV *const isa_hash = newHV(); |
200 | /* Linearisation didn't build it for us, so do it here. */ |
201 | SV *const *svp = AvARRAY(isa); |
202 | SV *const *const svp_end = svp + AvFILLp(isa) + 1; |
203 | const HEK *const canon_name = HvNAME_HEK(stash); |
204 | |
205 | while (svp < svp_end) { |
206 | (void) hv_store_ent(isa_hash, *svp++, &PL_sv_undef, 0); |
207 | } |
208 | |
209 | (void) hv_common(isa_hash, NULL, HEK_KEY(canon_name), |
210 | HEK_LEN(canon_name), HEK_FLAGS(canon_name), |
211 | HV_FETCH_ISSTORE, &PL_sv_undef, |
212 | HEK_HASH(canon_name)); |
213 | (void) hv_store(isa_hash, "UNIVERSAL", 9, &PL_sv_undef, 0); |
214 | |
ed09b296 |
215 | SvREADONLY_on(isa_hash); |
216 | |
6e4aef59 |
217 | meta->isa = isa_hash; |
218 | } |
219 | } |
a49ba3fc |
220 | return meta->isa; |
221 | } |
222 | |
e1a479c5 |
223 | /* |
224 | =for apidoc mro_get_linear_isa_dfs |
225 | |
226 | Returns the Depth-First Search linearization of @ISA |
227 | the given stash. The return value is a read-only AV*. |
228 | C<level> should be 0 (it is used internally in this |
229 | function's recursion). |
230 | |
1c908217 |
231 | You are responsible for C<SvREFCNT_inc()> on the |
232 | return value if you plan to store it anywhere |
233 | semi-permanently (otherwise it might be deleted |
234 | out from under you the next time the cache is |
235 | invalidated). |
236 | |
e1a479c5 |
237 | =cut |
238 | */ |
4befac30 |
239 | static AV* |
94d1e706 |
240 | S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) |
e1a479c5 |
241 | { |
242 | AV* retval; |
243 | GV** gvp; |
244 | GV* gv; |
245 | AV* av; |
190d0b22 |
246 | const HEK* stashhek; |
e1a479c5 |
247 | struct mro_meta* meta; |
a49ba3fc |
248 | SV *our_name; |
249 | HV *stored; |
e1a479c5 |
250 | |
7918f24d |
251 | PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA_DFS; |
e1a479c5 |
252 | assert(HvAUX(stash)); |
253 | |
190d0b22 |
254 | stashhek = HvNAME_HEK(stash); |
255 | if (!stashhek) |
1e05feb3 |
256 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); |
e1a479c5 |
257 | |
258 | if (level > 100) |
259 | Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", |
190d0b22 |
260 | HEK_KEY(stashhek)); |
e1a479c5 |
261 | |
262 | meta = HvMROMETA(stash); |
1c908217 |
263 | |
264 | /* return cache if valid */ |
a3e6e81e |
265 | if((retval = MUTABLE_AV(MRO_GET_PRIVATE_DATA(meta, &dfs_alg)))) { |
e1a479c5 |
266 | return retval; |
267 | } |
268 | |
269 | /* not in cache, make a new one */ |
1c908217 |
270 | |
ad64d0ec |
271 | retval = MUTABLE_AV(sv_2mortal(MUTABLE_SV(newAV()))); |
a49ba3fc |
272 | /* We use this later in this function, but don't need a reference to it |
273 | beyond the end of this function, so reference count is fine. */ |
274 | our_name = newSVhek(stashhek); |
275 | av_push(retval, our_name); /* add ourselves at the top */ |
e1a479c5 |
276 | |
1c908217 |
277 | /* fetch our @ISA */ |
e1a479c5 |
278 | gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); |
279 | av = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; |
280 | |
a49ba3fc |
281 | /* "stored" is used to keep track of all of the classnames we have added to |
282 | the MRO so far, so we can do a quick exists check and avoid adding |
283 | duplicate classnames to the MRO as we go. |
284 | It's then retained to be re-used as a fast lookup for ->isa(), by adding |
285 | our own name and "UNIVERSAL" to it. */ |
286 | |
ad64d0ec |
287 | stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); |
1c908217 |
288 | |
a49ba3fc |
289 | if(av && AvFILLp(av) >= 0) { |
1c908217 |
290 | |
ffd8da72 |
291 | SV **svp = AvARRAY(av); |
292 | I32 items = AvFILLp(av) + 1; |
1c908217 |
293 | |
294 | /* foreach(@ISA) */ |
e1a479c5 |
295 | while (items--) { |
296 | SV* const sv = *svp++; |
297 | HV* const basestash = gv_stashsv(sv, 0); |
ffd8da72 |
298 | SV *const *subrv_p; |
299 | I32 subrv_items; |
e1a479c5 |
300 | |
301 | if (!basestash) { |
1c908217 |
302 | /* if no stash exists for this @ISA member, |
303 | simply add it to the MRO and move on */ |
ffd8da72 |
304 | subrv_p = &sv; |
305 | subrv_items = 1; |
e1a479c5 |
306 | } |
307 | else { |
1c908217 |
308 | /* otherwise, recurse into ourselves for the MRO |
b1d0c68a |
309 | of this @ISA member, and append their MRO to ours. |
310 | The recursive call could throw an exception, which |
311 | has memory management implications here, hence the use of |
312 | the mortal. */ |
ffd8da72 |
313 | const AV *const subrv |
314 | = mro_get_linear_isa_dfs(basestash, level + 1); |
315 | |
316 | subrv_p = AvARRAY(subrv); |
317 | subrv_items = AvFILLp(subrv) + 1; |
318 | } |
319 | while(subrv_items--) { |
320 | SV *const subsv = *subrv_p++; |
8e45cc2b |
321 | /* LVALUE fetch will create a new undefined SV if necessary |
322 | */ |
323 | HE *const he = hv_fetch_ent(stored, subsv, 1, 0); |
324 | assert(he); |
325 | if(HeVAL(he) != &PL_sv_undef) { |
326 | /* It was newly created. Steal it for our new SV, and |
327 | replace it in the hash with the "real" thing. */ |
328 | SV *const val = HeVAL(he); |
f46ee248 |
329 | HEK *const key = HeKEY_hek(he); |
8e45cc2b |
330 | |
331 | HeVAL(he) = &PL_sv_undef; |
f46ee248 |
332 | /* Save copying by making a shared hash key scalar. We |
333 | inline this here rather than calling Perl_newSVpvn_share |
334 | because we already have the scalar, and we already have |
335 | the hash key. */ |
336 | assert(SvTYPE(val) == SVt_NULL); |
337 | sv_upgrade(val, SVt_PV); |
338 | SvPV_set(val, HEK_KEY(share_hek_hek(key))); |
339 | SvCUR_set(val, HEK_LEN(key)); |
340 | SvREADONLY_on(val); |
341 | SvFAKE_on(val); |
342 | SvPOK_on(val); |
343 | if (HEK_UTF8(key)) |
344 | SvUTF8_on(val); |
345 | |
8e45cc2b |
346 | av_push(retval, val); |
ffd8da72 |
347 | } |
e1a479c5 |
348 | } |
349 | } |
350 | } |
351 | |
ed09b296 |
352 | (void) hv_store_ent(stored, our_name, &PL_sv_undef, 0); |
353 | (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); |
354 | |
355 | SvREFCNT_inc_simple_void_NN(stored); |
356 | SvTEMP_off(stored); |
357 | SvREADONLY_on(stored); |
358 | |
359 | meta->isa = stored; |
360 | |
0fd7ece8 |
361 | /* now that we're past the exception dangers, grab our own reference to |
362 | the AV we're about to use for the result. The reference owned by the |
363 | mortals' stack will be released soon, so everything will balance. */ |
364 | SvREFCNT_inc_simple_void_NN(retval); |
365 | SvTEMP_off(retval); |
fdef73f9 |
366 | |
1c908217 |
367 | /* we don't want anyone modifying the cache entry but us, |
368 | and we do so by replacing it completely */ |
e1a479c5 |
369 | SvREADONLY_on(retval); |
1c908217 |
370 | |
a3e6e81e |
371 | return MUTABLE_AV(Perl_mro_set_private_data(aTHX_ meta, &dfs_alg, |
fa60396f |
372 | MUTABLE_SV(retval))); |
e1a479c5 |
373 | } |
374 | |
375 | /* |
e1a479c5 |
376 | =for apidoc mro_get_linear_isa |
377 | |
378 | Returns either C<mro_get_linear_isa_c3> or |
379 | C<mro_get_linear_isa_dfs> for the given stash, |
380 | dependant upon which MRO is in effect |
381 | for that stash. The return value is a |
382 | read-only AV*. |
383 | |
1c908217 |
384 | You are responsible for C<SvREFCNT_inc()> on the |
385 | return value if you plan to store it anywhere |
386 | semi-permanently (otherwise it might be deleted |
387 | out from under you the next time the cache is |
388 | invalidated). |
389 | |
e1a479c5 |
390 | =cut |
391 | */ |
392 | AV* |
393 | Perl_mro_get_linear_isa(pTHX_ HV *stash) |
394 | { |
395 | struct mro_meta* meta; |
2c7f4b87 |
396 | |
7918f24d |
397 | PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA; |
2c7f4b87 |
398 | if(!SvOOK(stash)) |
399 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); |
e1a479c5 |
400 | |
401 | meta = HvMROMETA(stash); |
3d76853f |
402 | if (!meta->mro_which) |
14f97ce6 |
403 | Perl_croak(aTHX_ "panic: invalid MRO!"); |
3d76853f |
404 | return meta->mro_which->resolve(aTHX_ stash, 0); |
e1a479c5 |
405 | } |
406 | |
407 | /* |
408 | =for apidoc mro_isa_changed_in |
409 | |
1c908217 |
410 | Takes the necessary steps (cache invalidations, mostly) |
e1a479c5 |
411 | when the @ISA of the given package has changed. Invoked |
412 | by the C<setisa> magic, should not need to invoke directly. |
413 | |
414 | =cut |
415 | */ |
416 | void |
417 | Perl_mro_isa_changed_in(pTHX_ HV* stash) |
418 | { |
419 | dVAR; |
420 | HV* isarev; |
421 | AV* linear_mro; |
422 | HE* iter; |
423 | SV** svp; |
424 | I32 items; |
1e05feb3 |
425 | bool is_universal; |
2c7f4b87 |
426 | struct mro_meta * meta; |
e1a479c5 |
427 | |
0fa56319 |
428 | const char * const stashname = HvNAME_get(stash); |
429 | const STRLEN stashname_len = HvNAMELEN_get(stash); |
e1a479c5 |
430 | |
7918f24d |
431 | PERL_ARGS_ASSERT_MRO_ISA_CHANGED_IN; |
432 | |
2c7f4b87 |
433 | if(!stashname) |
434 | Perl_croak(aTHX_ "Can't call mro_isa_changed_in() on anonymous symbol table"); |
435 | |
e1a479c5 |
436 | /* wipe out the cached linearizations for this stash */ |
2c7f4b87 |
437 | meta = HvMROMETA(stash); |
9953ff72 |
438 | if (meta->mro_linear_all) { |
439 | SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all)); |
440 | meta->mro_linear_all = NULL; |
553e831a |
441 | /* This is just acting as a shortcut pointer. */ |
3a6fa573 |
442 | meta->mro_linear_current = NULL; |
443 | } else if (meta->mro_linear_current) { |
553e831a |
444 | /* Only the current MRO is stored, so this owns the data. */ |
3a6fa573 |
445 | SvREFCNT_dec(meta->mro_linear_current); |
446 | meta->mro_linear_current = NULL; |
553e831a |
447 | } |
5782d502 |
448 | if (meta->isa) { |
449 | SvREFCNT_dec(meta->isa); |
450 | meta->isa = NULL; |
451 | } |
e1a479c5 |
452 | |
70cd14a1 |
453 | /* Inc the package generation, since our @ISA changed */ |
454 | meta->pkg_gen++; |
455 | |
e1a479c5 |
456 | /* Wipe the global method cache if this package |
457 | is UNIVERSAL or one of its parents */ |
dd69841b |
458 | |
459 | svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); |
85fbaab2 |
460 | isarev = svp ? MUTABLE_HV(*svp) : NULL; |
dd69841b |
461 | |
462 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) |
463 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { |
e1a479c5 |
464 | PL_sub_generation++; |
dd69841b |
465 | is_universal = TRUE; |
466 | } |
1e05feb3 |
467 | else { /* Wipe the local method cache otherwise */ |
dd69841b |
468 | meta->cache_gen++; |
1e05feb3 |
469 | is_universal = FALSE; |
470 | } |
e1a479c5 |
471 | |
472 | /* wipe next::method cache too */ |
473 | if(meta->mro_nextmethod) hv_clear(meta->mro_nextmethod); |
1e05feb3 |
474 | |
e1a479c5 |
475 | /* Iterate the isarev (classes that are our children), |
476 | wiping out their linearization and method caches */ |
dd69841b |
477 | if(isarev) { |
e1a479c5 |
478 | hv_iterinit(isarev); |
479 | while((iter = hv_iternext(isarev))) { |
ec49eb61 |
480 | I32 len; |
481 | const char* const revkey = hv_iterkey(iter, &len); |
482 | HV* revstash = gv_stashpvn(revkey, len, 0); |
bc2cbbac |
483 | struct mro_meta* revmeta; |
484 | |
485 | if(!revstash) continue; |
486 | revmeta = HvMROMETA(revstash); |
9953ff72 |
487 | if (revmeta->mro_linear_all) { |
488 | SvREFCNT_dec(MUTABLE_SV(revmeta->mro_linear_all)); |
489 | revmeta->mro_linear_all = NULL; |
553e831a |
490 | /* This is just acting as a shortcut pointer. */ |
3a6fa573 |
491 | revmeta->mro_linear_current = NULL; |
492 | } else if (revmeta->mro_linear_current) { |
553e831a |
493 | /* Only the current MRO is stored, so this owns the data. */ |
3a6fa573 |
494 | SvREFCNT_dec(revmeta->mro_linear_current); |
495 | revmeta->mro_linear_current = NULL; |
553e831a |
496 | } |
dd69841b |
497 | if(!is_universal) |
498 | revmeta->cache_gen++; |
e1a479c5 |
499 | if(revmeta->mro_nextmethod) |
500 | hv_clear(revmeta->mro_nextmethod); |
501 | } |
502 | } |
503 | |
1c908217 |
504 | /* Now iterate our MRO (parents), and do a few things: |
505 | 1) instantiate with the "fake" flag if they don't exist |
506 | 2) flag them as universal if we are universal |
507 | 3) Add everything from our isarev to their isarev |
508 | */ |
509 | |
510 | /* We're starting at the 2nd element, skipping ourselves here */ |
e1a479c5 |
511 | linear_mro = mro_get_linear_isa(stash); |
512 | svp = AvARRAY(linear_mro) + 1; |
513 | items = AvFILLp(linear_mro); |
1c908217 |
514 | |
e1a479c5 |
515 | while (items--) { |
516 | SV* const sv = *svp++; |
e1a479c5 |
517 | HV* mroisarev; |
518 | |
117b69ca |
519 | HE *he = hv_fetch_ent(PL_isarev, sv, TRUE, 0); |
520 | |
521 | /* That fetch should not fail. But if it had to create a new SV for |
4ea50411 |
522 | us, then will need to upgrade it to an HV (which sv_upgrade() can |
523 | now do for us. */ |
117b69ca |
524 | |
85fbaab2 |
525 | mroisarev = MUTABLE_HV(HeVAL(he)); |
e1a479c5 |
526 | |
ad64d0ec |
527 | SvUPGRADE(MUTABLE_SV(mroisarev), SVt_PVHV); |
117b69ca |
528 | |
25270bc0 |
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 | |
04fe65b0 |
534 | (void)hv_store(mroisarev, stashname, stashname_len, &PL_sv_yes, 0); |
e1a479c5 |
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); |
04fe65b0 |
541 | (void)hv_store(mroisarev, revkey, revkeylen, &PL_sv_yes, 0); |
e1a479c5 |
542 | } |
543 | } |
544 | } |
545 | } |
546 | |
547 | /* |
548 | =for apidoc mro_method_changed_in |
549 | |
47c9dd14 |
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 |
553 | |
554 | Ideally, all instances of C<PL_sub_generation++> in |
dd69841b |
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 |
564 | 1) Directly manipulating the stash HV entries from |
565 | XS code. |
e1a479c5 |
566 | |
dd69841b |
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 |
574 | |
575 | =cut |
576 | */ |
577 | void |
578 | Perl_mro_method_changed_in(pTHX_ HV *stash) |
579 | { |
1e05feb3 |
580 | const char * const stashname = HvNAME_get(stash); |
581 | const STRLEN stashname_len = HvNAMELEN_get(stash); |
dd69841b |
582 | |
1e05feb3 |
583 | SV ** const svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); |
85fbaab2 |
584 | HV * const isarev = svp ? MUTABLE_HV(*svp) : NULL; |
e1a479c5 |
585 | |
7918f24d |
586 | PERL_ARGS_ASSERT_MRO_METHOD_CHANGED_IN; |
587 | |
2c7f4b87 |
588 | if(!stashname) |
589 | Perl_croak(aTHX_ "Can't call mro_method_changed_in() on anonymous symbol table"); |
590 | |
70cd14a1 |
591 | /* Inc the package generation, since a local method changed */ |
592 | HvMROMETA(stash)->pkg_gen++; |
593 | |
e1a479c5 |
594 | /* If stash is UNIVERSAL, or one of UNIVERSAL's parents, |
595 | invalidate all method caches globally */ |
dd69841b |
596 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) |
597 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { |
e1a479c5 |
598 | PL_sub_generation++; |
599 | return; |
600 | } |
601 | |
602 | /* else, invalidate the method caches of all child classes, |
603 | but not itself */ |
dd69841b |
604 | if(isarev) { |
1e05feb3 |
605 | HE* iter; |
606 | |
e1a479c5 |
607 | hv_iterinit(isarev); |
608 | while((iter = hv_iternext(isarev))) { |
ec49eb61 |
609 | I32 len; |
610 | const char* const revkey = hv_iterkey(iter, &len); |
611 | HV* const revstash = gv_stashpvn(revkey, len, 0); |
bc2cbbac |
612 | struct mro_meta* mrometa; |
613 | |
614 | if(!revstash) continue; |
615 | mrometa = HvMROMETA(revstash); |
dd69841b |
616 | mrometa->cache_gen++; |
e1a479c5 |
617 | if(mrometa->mro_nextmethod) |
618 | hv_clear(mrometa->mro_nextmethod); |
619 | } |
620 | } |
621 | } |
622 | |
31b9005d |
623 | void |
624 | Perl_mro_set_mro(pTHX_ struct mro_meta *const meta, SV *const name) |
625 | { |
626 | const struct mro_alg *const which = Perl_mro_get_from_name(aTHX_ name); |
627 | |
628 | PERL_ARGS_ASSERT_MRO_SET_MRO; |
629 | |
630 | if (!which) |
631 | Perl_croak(aTHX_ "Invalid mro name: '%"SVf"'", name); |
632 | |
633 | if(meta->mro_which != which) { |
9953ff72 |
634 | if (meta->mro_linear_current && !meta->mro_linear_all) { |
31b9005d |
635 | /* If we were storing something directly, put it in the hash before |
636 | we lose it. */ |
637 | Perl_mro_set_private_data(aTHX_ meta, meta->mro_which, |
3a6fa573 |
638 | MUTABLE_SV(meta->mro_linear_current)); |
31b9005d |
639 | } |
640 | meta->mro_which = which; |
641 | /* Scrub our cached pointer to the private data. */ |
3a6fa573 |
642 | meta->mro_linear_current = NULL; |
31b9005d |
643 | /* Only affects local method cache, not |
644 | even child classes */ |
645 | meta->cache_gen++; |
646 | if(meta->mro_nextmethod) |
647 | hv_clear(meta->mro_nextmethod); |
648 | } |
649 | } |
650 | |
e1a479c5 |
651 | #include "XSUB.h" |
652 | |
e1a479c5 |
653 | XS(XS_mro_method_changed_in); |
e1a479c5 |
654 | |
655 | void |
656 | Perl_boot_core_mro(pTHX) |
657 | { |
658 | dVAR; |
659 | static const char file[] = __FILE__; |
660 | |
a3e6e81e |
661 | Perl_mro_register(aTHX_ &dfs_alg); |
a3e6e81e |
662 | |
e1a479c5 |
663 | newXSproto("mro::method_changed_in", XS_mro_method_changed_in, file, "$"); |
e1a479c5 |
664 | } |
665 | |
e1a479c5 |
666 | XS(XS_mro_method_changed_in) |
667 | { |
668 | dVAR; |
669 | dXSARGS; |
670 | SV* classname; |
671 | HV* class_stash; |
672 | |
e1a479c5 |
673 | if(items != 1) |
afa74d42 |
674 | croak_xs_usage(cv, "classname"); |
e1a479c5 |
675 | |
676 | classname = ST(0); |
677 | |
678 | class_stash = gv_stashsv(classname, 0); |
679 | if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); |
680 | |
681 | mro_method_changed_in(class_stash); |
682 | |
683 | XSRETURN_EMPTY; |
684 | } |
685 | |
e1a479c5 |
686 | /* |
687 | * Local variables: |
688 | * c-indentation-style: bsd |
689 | * c-basic-offset: 4 |
690 | * indent-tabs-mode: t |
691 | * End: |
692 | * |
693 | * ex: set ts=8 sts=4 sw=4 noet: |
694 | */ |