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e1a479c5 BB |
1 | /* mro.c |
2 | * | |
3 | * Copyright (c) 2007 Brandon L Black | |
1129b882 | 4 | * Copyright (c) 2007, 2008 Larry Wall and others |
e1a479c5 BB |
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 TC |
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 RGS |
16 | */ |
17 | ||
18 | /* | |
e1a479c5 BB |
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 BB |
28 | #include "perl.h" |
29 | ||
a3e6e81e NC |
30 | static const struct mro_alg dfs_alg = |
31 | {S_mro_get_linear_isa_dfs, "dfs", 3, 0, 0}; | |
3d76853f | 32 | |
fa60396f NC |
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 NC |
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 NC |
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 NC |
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 NC |
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 NC |
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 NC |
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 NC |
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 NC |
89 | } |
90 | ||
9953ff72 | 91 | if (!Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL, |
fa60396f NC |
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 NC |
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 NC |
108 | data = (SV **)Perl_hv_common(aTHX_ PL_registered_mros, name, NULL, 0, 0, |
109 | HV_FETCH_JUST_SV, NULL, 0); | |
a3e6e81e NC |
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 NC |
131 | } |
132 | ||
e1a479c5 BB |
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 BB |
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 BB |
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 BB |
156 | struct mro_meta* newmeta; |
157 | ||
7918f24d | 158 | PERL_ARGS_ASSERT_MRO_META_DUP; |
e1a479c5 | 159 | |
33e12d9d NC |
160 | Newx(newmeta, 1, struct mro_meta); |
161 | Copy(smeta, newmeta, 1, struct mro_meta); | |
162 | ||
9953ff72 NC |
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 NC |
166 | /* This is just acting as a shortcut pointer, and will be automatically |
167 | updated on the first get. */ | |
3a6fa573 NC |
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 NC |
173 | } |
174 | ||
33e12d9d NC |
175 | if (newmeta->mro_nextmethod) |
176 | newmeta->mro_nextmethod | |
a09252eb | 177 | = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->mro_nextmethod, param)); |
a49ba3fc NC |
178 | if (newmeta->isa) |
179 | newmeta->isa | |
a09252eb | 180 | = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->isa, param)); |
e1a479c5 BB |
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 RGS |
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 BB |
201 | =cut |
202 | */ | |
4befac30 | 203 | static AV* |
94d1e706 | 204 | S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level) |
e1a479c5 BB |
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 BB |
216 | assert(HvAUX(stash)); |
217 | ||
190d0b22 NC |
218 | stashhek = HvNAME_HEK(stash); |
219 | if (!stashhek) | |
1e05feb3 | 220 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); |
e1a479c5 BB |
221 | |
222 | if (level > 100) | |
223 | Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'", | |
190d0b22 | 224 | HEK_KEY(stashhek)); |
e1a479c5 BB |
225 | |
226 | meta = HvMROMETA(stash); | |
1c908217 RGS |
227 | |
228 | /* return cache if valid */ | |
a3e6e81e | 229 | if((retval = MUTABLE_AV(MRO_GET_PRIVATE_DATA(meta, &dfs_alg)))) { |
e1a479c5 BB |
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 NC |
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 BB |
242 | gvp = (GV**)hv_fetchs(stash, "ISA", FALSE); |
243 | av = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL; | |
244 | ||
a49ba3fc NC |
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 NC |
253 | SV **svp = AvARRAY(av); |
254 | I32 items = AvFILLp(av) + 1; | |
1c908217 RGS |
255 | |
256 | /* foreach(@ISA) */ | |
e1a479c5 BB |
257 | while (items--) { |
258 | SV* const sv = *svp++; | |
259 | HV* const basestash = gv_stashsv(sv, 0); | |
ffd8da72 NC |
260 | SV *const *subrv_p; |
261 | I32 subrv_items; | |
e1a479c5 BB |
262 | |
263 | if (!basestash) { | |
1c908217 RGS |
264 | /* if no stash exists for this @ISA member, |
265 | simply add it to the MRO and move on */ | |
ffd8da72 NC |
266 | subrv_p = &sv; |
267 | subrv_items = 1; | |
e1a479c5 BB |
268 | } |
269 | else { | |
1c908217 | 270 | /* otherwise, recurse into ourselves for the MRO |
b1d0c68a NC |
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 NC |
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 NC |
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 NC |
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 NC |
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 NC |
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 BB |
351 | } |
352 | ||
ed09b296 | 353 | (void) hv_store_ent(stored, our_name, &PL_sv_undef, 0); |
ed09b296 NC |
354 | |
355 | SvREFCNT_inc_simple_void_NN(stored); | |
356 | SvTEMP_off(stored); | |
357 | SvREADONLY_on(stored); | |
358 | ||
359 | meta->isa = stored; | |
360 | ||
0fd7ece8 NC |
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 RGS |
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 BB |
373 | } |
374 | ||
375 | /* | |
e1a479c5 BB |
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 RGS |
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 BB |
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 BB |
398 | if(!SvOOK(stash)) |
399 | Perl_croak(aTHX_ "Can't linearize anonymous symbol table"); | |
e1a479c5 BB |
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 BB |
405 | } |
406 | ||
407 | /* | |
408 | =for apidoc mro_isa_changed_in | |
409 | ||
1c908217 | 410 | Takes the necessary steps (cache invalidations, mostly) |
e1a479c5 BB |
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 RGS |
428 | const char * const stashname = HvNAME_get(stash); |
429 | const STRLEN stashname_len = HvNAMELEN_get(stash); | |
e1a479c5 | 430 | |
7918f24d NC |
431 | PERL_ARGS_ASSERT_MRO_ISA_CHANGED_IN; |
432 | ||
2c7f4b87 BB |
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 NC |
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 NC |
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 NC |
445 | SvREFCNT_dec(meta->mro_linear_current); |
446 | meta->mro_linear_current = NULL; | |
553e831a | 447 | } |
5782d502 NC |
448 | if (meta->isa) { |
449 | SvREFCNT_dec(meta->isa); | |
450 | meta->isa = NULL; | |
451 | } | |
e1a479c5 | 452 | |
70cd14a1 CB |
453 | /* Inc the package generation, since our @ISA changed */ |
454 | meta->pkg_gen++; | |
455 | ||
e1a479c5 BB |
456 | /* Wipe the global method cache if this package |
457 | is UNIVERSAL or one of its parents */ | |
dd69841b BB |
458 | |
459 | svp = hv_fetch(PL_isarev, stashname, stashname_len, 0); | |
85fbaab2 | 460 | isarev = svp ? MUTABLE_HV(*svp) : NULL; |
dd69841b BB |
461 | |
462 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) | |
463 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { | |
e1a479c5 | 464 | PL_sub_generation++; |
dd69841b BB |
465 | is_universal = TRUE; |
466 | } | |
1e05feb3 | 467 | else { /* Wipe the local method cache otherwise */ |
dd69841b | 468 | meta->cache_gen++; |
1e05feb3 AL |
469 | is_universal = FALSE; |
470 | } | |
e1a479c5 BB |
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 BB |
478 | hv_iterinit(isarev); |
479 | while((iter = hv_iternext(isarev))) { | |
ec49eb61 NC |
480 | I32 len; |
481 | const char* const revkey = hv_iterkey(iter, &len); | |
482 | HV* revstash = gv_stashpvn(revkey, len, 0); | |
bc2cbbac BB |
483 | struct mro_meta* revmeta; |
484 | ||
485 | if(!revstash) continue; | |
486 | revmeta = HvMROMETA(revstash); | |
9953ff72 NC |
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 NC |
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 NC |
494 | SvREFCNT_dec(revmeta->mro_linear_current); |
495 | revmeta->mro_linear_current = NULL; | |
553e831a | 496 | } |
dd69841b BB |
497 | if(!is_universal) |
498 | revmeta->cache_gen++; | |
e1a479c5 BB |
499 | if(revmeta->mro_nextmethod) |
500 | hv_clear(revmeta->mro_nextmethod); | |
1375cf1c NC |
501 | if (revmeta->isa) { |
502 | SvREFCNT_dec(revmeta->isa); | |
503 | revmeta->isa = NULL; | |
504 | } | |
e1a479c5 BB |
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 | ||
117b69ca NC |
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 NC |
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 NC |
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 BB |
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 BB |
546 | } |
547 | } | |
548 | } | |
549 | } | |
550 | ||
551 | /* | |
552 | =for apidoc mro_method_changed_in | |
553 | ||
47c9dd14 BB |
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 BB |
557 | |
558 | Ideally, all instances of C<PL_sub_generation++> in | |
dd69841b BB |
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 BB |
568 | 1) Directly manipulating the stash HV entries from |
569 | XS code. | |
e1a479c5 | 570 | |
dd69841b BB |
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 BB |
578 | |
579 | =cut | |
580 | */ | |
581 | void | |
582 | Perl_mro_method_changed_in(pTHX_ HV *stash) | |
583 | { | |
1e05feb3 AL |
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 NC |
590 | PERL_ARGS_ASSERT_MRO_METHOD_CHANGED_IN; |
591 | ||
2c7f4b87 BB |
592 | if(!stashname) |
593 | Perl_croak(aTHX_ "Can't call mro_method_changed_in() on anonymous symbol table"); | |
594 | ||
70cd14a1 CB |
595 | /* Inc the package generation, since a local method changed */ |
596 | HvMROMETA(stash)->pkg_gen++; | |
597 | ||
e1a479c5 BB |
598 | /* If stash is UNIVERSAL, or one of UNIVERSAL's parents, |
599 | invalidate all method caches globally */ | |
dd69841b BB |
600 | if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL")) |
601 | || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) { | |
e1a479c5 BB |
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 AL |
609 | HE* iter; |
610 | ||
e1a479c5 BB |
611 | hv_iterinit(isarev); |
612 | while((iter = hv_iternext(isarev))) { | |
ec49eb61 NC |
613 | I32 len; |
614 | const char* const revkey = hv_iterkey(iter, &len); | |
615 | HV* const revstash = gv_stashpvn(revkey, len, 0); | |
bc2cbbac BB |
616 | struct mro_meta* mrometa; |
617 | ||
618 | if(!revstash) continue; | |
619 | mrometa = HvMROMETA(revstash); | |
dd69841b | 620 | mrometa->cache_gen++; |
e1a479c5 BB |
621 | if(mrometa->mro_nextmethod) |
622 | hv_clear(mrometa->mro_nextmethod); | |
623 | } | |
624 | } | |
625 | } | |
626 | ||
31b9005d NC |
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 NC |
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 NC |
643 | } |
644 | meta->mro_which = which; | |
645 | /* Scrub our cached pointer to the private data. */ | |
3a6fa573 | 646 | meta->mro_linear_current = NULL; |
31b9005d NC |
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 BB |
655 | #include "XSUB.h" |
656 | ||
e1a479c5 | 657 | XS(XS_mro_method_changed_in); |
e1a479c5 BB |
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 BB |
668 | } |
669 | ||
e1a479c5 BB |
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 BB |
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 BB |
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 | */ |