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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 |
a09252eb |
165 | = MUTABLE_HV(sv_dup_inc((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 |
a09252eb |
172 | = sv_dup_inc((const SV *)newmeta->mro_linear_current, param); |
553e831a |
173 | } |
174 | |
33e12d9d |
175 | if (newmeta->mro_nextmethod) |
176 | newmeta->mro_nextmethod |
a09252eb |
177 | = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->mro_nextmethod, param)); |
a49ba3fc |
178 | if (newmeta->isa) |
179 | newmeta->isa |
a09252eb |
180 | = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->isa, param)); |
e1a479c5 |
181 | |
182 | return newmeta; |
183 | } |
184 | |
185 | #endif /* USE_ITHREADS */ |
186 | |
187 | /* |
188 | =for apidoc mro_get_linear_isa_dfs |
189 | |
190 | Returns the Depth-First Search linearization of @ISA |
191 | the given stash. The return value is a read-only AV*. |
192 | C<level> should be 0 (it is used internally in this |
193 | function's recursion). |
194 | |
1c908217 |
195 | You are responsible for C<SvREFCNT_inc()> on the |
196 | return value if you plan to store it anywhere |
197 | semi-permanently (otherwise it might be deleted |
198 | out from under you the next time the cache is |
199 | invalidated). |
200 | |
e1a479c5 |
201 | =cut |
202 | */ |
4befac30 |
203 | static AV* |
94d1e706 |
204 | S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) |
e1a479c5 |
205 | { |
206 | AV* retval; |
207 | GV** gvp; |
208 | GV* gv; |
209 | AV* av; |
190d0b22 |
210 | const HEK* stashhek; |
e1a479c5 |
211 | struct mro_meta* meta; |
a49ba3fc |
212 | SV *our_name; |
73519bd0 |
213 | HV *stored = NULL; |
e1a479c5 |
214 | |
7918f24d |
215 | PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA_DFS; |
e1a479c5 |
216 | assert(HvAUX(stash)); |
217 | |
190d0b22 |
218 | stashhek = HvNAME_HEK(stash); |
219 | if (!stashhek) |
1e05feb3 |
220 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); |
e1a479c5 |
221 | |
222 | if (level > 100) |
223 | Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", |
190d0b22 |
224 | HEK_KEY(stashhek)); |
e1a479c5 |
225 | |
226 | meta = HvMROMETA(stash); |
1c908217 |
227 | |
228 | /* return cache if valid */ |
a3e6e81e |
229 | if((retval = MUTABLE_AV(MRO_GET_PRIVATE_DATA(meta, &dfs_alg)))) { |
e1a479c5 |
230 | return retval; |
231 | } |
232 | |
233 | /* not in cache, make a new one */ |
1c908217 |
234 | |
ad64d0ec |
235 | retval = MUTABLE_AV(sv_2mortal(MUTABLE_SV(newAV()))); |
a49ba3fc |
236 | /* We use this later in this function, but don't need a reference to it |
237 | beyond the end of this function, so reference count is fine. */ |
238 | our_name = newSVhek(stashhek); |
239 | av_push(retval, our_name); /* add ourselves at the top */ |
e1a479c5 |
240 | |
1c908217 |
241 | /* fetch our @ISA */ |
e1a479c5 |
242 | gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); |
243 | av = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; |
244 | |
a49ba3fc |
245 | /* "stored" is used to keep track of all of the classnames we have added to |
246 | the MRO so far, so we can do a quick exists check and avoid adding |
247 | duplicate classnames to the MRO as we go. |
248 | It's then retained to be re-used as a fast lookup for ->isa(), by adding |
249 | our own name and "UNIVERSAL" to it. */ |
250 | |
a49ba3fc |
251 | if(av && AvFILLp(av) >= 0) { |
1c908217 |
252 | |
ffd8da72 |
253 | SV **svp = AvARRAY(av); |
254 | I32 items = AvFILLp(av) + 1; |
1c908217 |
255 | |
256 | /* foreach(@ISA) */ |
e1a479c5 |
257 | while (items--) { |
258 | SV* const sv = *svp++; |
259 | HV* const basestash = gv_stashsv(sv, 0); |
ffd8da72 |
260 | SV *const *subrv_p; |
261 | I32 subrv_items; |
e1a479c5 |
262 | |
263 | if (!basestash) { |
1c908217 |
264 | /* if no stash exists for this @ISA member, |
265 | simply add it to the MRO and move on */ |
ffd8da72 |
266 | subrv_p = &sv; |
267 | subrv_items = 1; |
e1a479c5 |
268 | } |
269 | else { |
1c908217 |
270 | /* otherwise, recurse into ourselves for the MRO |
b1d0c68a |
271 | of this @ISA member, and append their MRO to ours. |
272 | The recursive call could throw an exception, which |
273 | has memory management implications here, hence the use of |
274 | the mortal. */ |
ffd8da72 |
275 | const AV *const subrv |
276 | = mro_get_linear_isa_dfs(basestash, level + 1); |
277 | |
278 | subrv_p = AvARRAY(subrv); |
279 | subrv_items = AvFILLp(subrv) + 1; |
280 | } |
73519bd0 |
281 | if (stored) { |
282 | while(subrv_items--) { |
283 | SV *const subsv = *subrv_p++; |
284 | /* LVALUE fetch will create a new undefined SV if necessary |
285 | */ |
286 | HE *const he = hv_fetch_ent(stored, subsv, 1, 0); |
287 | assert(he); |
288 | if(HeVAL(he) != &PL_sv_undef) { |
289 | /* It was newly created. Steal it for our new SV, and |
290 | replace it in the hash with the "real" thing. */ |
291 | SV *const val = HeVAL(he); |
292 | HEK *const key = HeKEY_hek(he); |
293 | |
294 | HeVAL(he) = &PL_sv_undef; |
295 | /* Save copying by making a shared hash key scalar. We |
296 | inline this here rather than calling |
297 | Perl_newSVpvn_share because we already have the |
298 | scalar, and we already have the hash key. */ |
299 | assert(SvTYPE(val) == SVt_NULL); |
300 | sv_upgrade(val, SVt_PV); |
301 | SvPV_set(val, HEK_KEY(share_hek_hek(key))); |
302 | SvCUR_set(val, HEK_LEN(key)); |
303 | SvREADONLY_on(val); |
304 | SvFAKE_on(val); |
305 | SvPOK_on(val); |
306 | if (HEK_UTF8(key)) |
307 | SvUTF8_on(val); |
308 | |
309 | av_push(retval, val); |
310 | } |
ffd8da72 |
311 | } |
73519bd0 |
312 | } else { |
313 | /* We are the first (or only) parent. We can short cut the |
314 | complexity above, because our @ISA is simply us prepended |
315 | to our parent's @ISA, and our ->isa cache is simply our |
316 | parent's, with our name added. */ |
317 | /* newSVsv() is slow. This code is only faster if we can avoid |
318 | it by ensuring that SVs in the arrays are shared hash key |
319 | scalar SVs, because we can "copy" them very efficiently. |
320 | Although to be fair, we can't *ensure* this, as a reference |
321 | to the internal array is returned by mro::get_linear_isa(), |
322 | so we'll have to be defensive just in case someone faffed |
323 | with it. */ |
324 | if (basestash) { |
325 | SV **svp; |
17eef65c |
326 | stored = MUTABLE_HV(sv_2mortal((SV*)newHVhv(HvMROMETA(basestash)->isa))); |
73519bd0 |
327 | av_extend(retval, subrv_items); |
328 | AvFILLp(retval) = subrv_items; |
329 | svp = AvARRAY(retval); |
330 | while(subrv_items--) { |
331 | SV *const val = *subrv_p++; |
332 | *++svp = SvIsCOW_shared_hash(val) |
333 | ? newSVhek(SvSHARED_HEK_FROM_PV(SvPVX(val))) |
334 | : newSVsv(val); |
335 | } |
336 | } else { |
337 | /* They have no stash. So create ourselves an ->isa cache |
338 | as if we'd copied it from what theirs should be. */ |
339 | stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); |
340 | (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); |
341 | av_push(retval, |
342 | newSVhek(HeKEY_hek(hv_store_ent(stored, sv, |
343 | &PL_sv_undef, 0)))); |
344 | } |
345 | } |
e1a479c5 |
346 | } |
73519bd0 |
347 | } else { |
348 | /* We have no parents. */ |
349 | stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV()))); |
350 | (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0); |
e1a479c5 |
351 | } |
352 | |
ed09b296 |
353 | (void) hv_store_ent(stored, our_name, &PL_sv_undef, 0); |
ed09b296 |
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), |
1375cf1c |
476 | wiping out their linearization, method and isa 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); |
1375cf1c |
501 | if (revmeta->isa) { |
502 | SvREFCNT_dec(revmeta->isa); |
503 | revmeta->isa = NULL; |
504 | } |
e1a479c5 |
505 | } |
506 | } |
507 | |
1c908217 |
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 |
515 | linear_mro = mro_get_linear_isa(stash); |
516 | svp = AvARRAY(linear_mro) + 1; |
517 | items = AvFILLp(linear_mro); |
1c908217 |
518 | |
e1a479c5 |
519 | while (items--) { |
520 | SV* const sv = *svp++; |
e1a479c5 |
521 | HV* mroisarev; |
522 | |
117b69ca |
523 | HE *he = hv_fetch_ent(PL_isarev, sv, TRUE, 0); |
524 | |
525 | /* That fetch should not fail. But if it had to create a new SV for |
4ea50411 |
526 | us, then will need to upgrade it to an HV (which sv_upgrade() can |
527 | now do for us. */ |
117b69ca |
528 | |
85fbaab2 |
529 | mroisarev = MUTABLE_HV(HeVAL(he)); |
e1a479c5 |
530 | |
ad64d0ec |
531 | SvUPGRADE(MUTABLE_SV(mroisarev), SVt_PVHV); |
117b69ca |
532 | |
25270bc0 |
533 | /* This hash only ever contains PL_sv_yes. Storing it over itself is |
534 | almost as cheap as calling hv_exists, so on aggregate we expect to |
535 | save time by not making two calls to the common HV code for the |
536 | case where it doesn't exist. */ |
537 | |
04fe65b0 |
538 | (void)hv_store(mroisarev, stashname, stashname_len, &PL_sv_yes, 0); |
e1a479c5 |
539 | |
540 | if(isarev) { |
541 | hv_iterinit(isarev); |
542 | while((iter = hv_iternext(isarev))) { |
dd69841b |
543 | I32 revkeylen; |
1e05feb3 |
544 | char* const revkey = hv_iterkey(iter, &revkeylen); |
04fe65b0 |
545 | (void)hv_store(mroisarev, revkey, revkeylen, &PL_sv_yes, 0); |
e1a479c5 |
546 | } |
547 | } |
548 | } |
549 | } |
550 | |
551 | /* |
552 | =for apidoc mro_method_changed_in |
553 | |
47c9dd14 |
554 | Invalidates method caching on any child classes |
555 | of the given stash, so that they might notice |
556 | the changes in this one. |
e1a479c5 |
557 | |
558 | Ideally, all instances of C<PL_sub_generation++> in |
dd69841b |
559 | perl source outside of C<mro.c> should be |
560 | replaced by calls to this. |
561 | |
562 | Perl automatically handles most of the common |
563 | ways a method might be redefined. However, there |
564 | are a few ways you could change a method in a stash |
565 | without the cache code noticing, in which case you |
566 | need to call this method afterwards: |
e1a479c5 |
567 | |
dd69841b |
568 | 1) Directly manipulating the stash HV entries from |
569 | XS code. |
e1a479c5 |
570 | |
dd69841b |
571 | 2) Assigning a reference to a readonly scalar |
572 | constant into a stash entry in order to create |
573 | a constant subroutine (like constant.pm |
574 | does). |
575 | |
576 | This same method is available from pure perl |
577 | via, C<mro::method_changed_in(classname)>. |
e1a479c5 |
578 | |
579 | =cut |
580 | */ |
581 | void |
582 | Perl_mro_method_changed_in(pTHX_ HV *stash) |
583 | { |
1e05feb3 |
584 | const char * const stashname = HvNAME_get(stash); |
585 | const STRLEN stashname_len = HvNAMELEN_get(stash); |
dd69841b |
586 | |
1e05feb3 |
587 | SV ** const svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); |
85fbaab2 |
588 | HV * const isarev = svp ? MUTABLE_HV(*svp) : NULL; |
e1a479c5 |
589 | |
7918f24d |
590 | PERL_ARGS_ASSERT_MRO_METHOD_CHANGED_IN; |
591 | |
2c7f4b87 |
592 | if(!stashname) |
593 | Perl_croak(aTHX_ "Can't call mro_method_changed_in() on anonymous symbol table"); |
594 | |
70cd14a1 |
595 | /* Inc the package generation, since a local method changed */ |
596 | HvMROMETA(stash)->pkg_gen++; |
597 | |
e1a479c5 |
598 | /* If stash is UNIVERSAL, or one of UNIVERSAL's parents, |
599 | invalidate all method caches globally */ |
dd69841b |
600 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) |
601 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { |
e1a479c5 |
602 | PL_sub_generation++; |
603 | return; |
604 | } |
605 | |
606 | /* else, invalidate the method caches of all child classes, |
607 | but not itself */ |
dd69841b |
608 | if(isarev) { |
1e05feb3 |
609 | HE* iter; |
610 | |
e1a479c5 |
611 | hv_iterinit(isarev); |
612 | while((iter = hv_iternext(isarev))) { |
ec49eb61 |
613 | I32 len; |
614 | const char* const revkey = hv_iterkey(iter, &len); |
615 | HV* const revstash = gv_stashpvn(revkey, len, 0); |
bc2cbbac |
616 | struct mro_meta* mrometa; |
617 | |
618 | if(!revstash) continue; |
619 | mrometa = HvMROMETA(revstash); |
dd69841b |
620 | mrometa->cache_gen++; |
e1a479c5 |
621 | if(mrometa->mro_nextmethod) |
622 | hv_clear(mrometa->mro_nextmethod); |
623 | } |
624 | } |
625 | } |
626 | |
31b9005d |
627 | void |
628 | Perl_mro_set_mro(pTHX_ struct mro_meta *const meta, SV *const name) |
629 | { |
630 | const struct mro_alg *const which = Perl_mro_get_from_name(aTHX_ name); |
631 | |
632 | PERL_ARGS_ASSERT_MRO_SET_MRO; |
633 | |
634 | if (!which) |
635 | Perl_croak(aTHX_ "Invalid mro name: '%"SVf"'", name); |
636 | |
637 | if(meta->mro_which != which) { |
9953ff72 |
638 | if (meta->mro_linear_current && !meta->mro_linear_all) { |
31b9005d |
639 | /* If we were storing something directly, put it in the hash before |
640 | we lose it. */ |
641 | Perl_mro_set_private_data(aTHX_ meta, meta->mro_which, |
3a6fa573 |
642 | MUTABLE_SV(meta->mro_linear_current)); |
31b9005d |
643 | } |
644 | meta->mro_which = which; |
645 | /* Scrub our cached pointer to the private data. */ |
3a6fa573 |
646 | meta->mro_linear_current = NULL; |
31b9005d |
647 | /* Only affects local method cache, not |
648 | even child classes */ |
649 | meta->cache_gen++; |
650 | if(meta->mro_nextmethod) |
651 | hv_clear(meta->mro_nextmethod); |
652 | } |
653 | } |
654 | |
e1a479c5 |
655 | #include "XSUB.h" |
656 | |
e1a479c5 |
657 | XS(XS_mro_method_changed_in); |
e1a479c5 |
658 | |
659 | void |
660 | Perl_boot_core_mro(pTHX) |
661 | { |
662 | dVAR; |
663 | static const char file[] = __FILE__; |
664 | |
a3e6e81e |
665 | Perl_mro_register(aTHX_ &dfs_alg); |
a3e6e81e |
666 | |
e1a479c5 |
667 | newXSproto("mro::method_changed_in", XS_mro_method_changed_in, file, "$"); |
e1a479c5 |
668 | } |
669 | |
e1a479c5 |
670 | XS(XS_mro_method_changed_in) |
671 | { |
672 | dVAR; |
673 | dXSARGS; |
674 | SV* classname; |
675 | HV* class_stash; |
676 | |
e1a479c5 |
677 | if(items != 1) |
afa74d42 |
678 | croak_xs_usage(cv, "classname"); |
e1a479c5 |
679 | |
680 | classname = ST(0); |
681 | |
682 | class_stash = gv_stashsv(classname, 0); |
683 | if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname)); |
684 | |
685 | mro_method_changed_in(class_stash); |
686 | |
687 | XSRETURN_EMPTY; |
688 | } |
689 | |
e1a479c5 |
690 | /* |
691 | * Local variables: |
692 | * c-indentation-style: bsd |
693 | * c-basic-offset: 4 |
694 | * indent-tabs-mode: t |
695 | * End: |
696 | * |
697 | * ex: set ts=8 sts=4 sw=4 noet: |
698 | */ |