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Fix package assignment with nested aliased packages
[perl5.git] / mro.c
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1/* mro.c
2 *
3 * Copyright (c) 2007 Brandon L Black
1129b882 4 * Copyright (c) 2007, 2008 Larry Wall and others
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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/*
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19=head1 MRO Functions
20
21These 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
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28#include "perl.h"
29
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30static const struct mro_alg dfs_alg =
31 {S_mro_get_linear_isa_dfs, "dfs", 3, 0, 0};
3d76853f 32
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33SV *
34Perl_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
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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
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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;
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50
51 return *data;
52}
53
54SV *
55Perl_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;
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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) {
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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);
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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;
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89 }
90
9953ff72 91 if (!Perl_hv_common(aTHX_ smeta->mro_linear_all, NULL,
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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
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102const struct mro_alg *
103Perl_mro_get_from_name(pTHX_ SV *name) {
104 SV **data;
105
106 PERL_ARGS_ASSERT_MRO_GET_FROM_NAME;
107
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108 data = (SV **)Perl_hv_common(aTHX_ PL_registered_mros, name, NULL, 0, 0,
109 HV_FETCH_JUST_SV, NULL, 0);
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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
117void
118Perl_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 }
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131}
132
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133struct mro_meta*
134Perl_mro_meta_init(pTHX_ HV* stash)
135{
9fe4aecf 136 struct mro_meta* newmeta;
e1a479c5 137
7918f24d 138 PERL_ARGS_ASSERT_MRO_META_INIT;
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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;
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146
147 return newmeta;
148}
149
150#if defined(USE_ITHREADS)
151
152/* for sv_dup on new threads */
153struct mro_meta*
154Perl_mro_meta_dup(pTHX_ struct mro_meta* smeta, CLONE_PARAMS* param)
155{
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156 struct mro_meta* newmeta;
157
7918f24d 158 PERL_ARGS_ASSERT_MRO_META_DUP;
e1a479c5 159
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160 Newx(newmeta, 1, struct mro_meta);
161 Copy(smeta, newmeta, 1, struct mro_meta);
162
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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));
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166 /* This is just acting as a shortcut pointer, and will be automatically
167 updated on the first get. */
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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);
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173 }
174
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175 if (newmeta->mro_nextmethod)
176 newmeta->mro_nextmethod
a09252eb 177 = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->mro_nextmethod, param));
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178 if (newmeta->isa)
179 newmeta->isa
a09252eb 180 = MUTABLE_HV(sv_dup_inc((const SV *)newmeta->isa, param));
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181
182 return newmeta;
183}
184
185#endif /* USE_ITHREADS */
186
187/*
188=for apidoc mro_get_linear_isa_dfs
189
190Returns the Depth-First Search linearization of @ISA
191the given stash. The return value is a read-only AV*.
192C<level> should be 0 (it is used internally in this
193function's recursion).
194
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195You are responsible for C<SvREFCNT_inc()> on the
196return value if you plan to store it anywhere
197semi-permanently (otherwise it might be deleted
198out from under you the next time the cache is
199invalidated).
200
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201=cut
202*/
4befac30 203static AV*
94d1e706 204S_mro_get_linear_isa_dfs(pTHX_ HV *stash, U32 level)
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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;
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216 assert(HvAUX(stash));
217
00169e2c
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218 stashhek
219 = HvAUX(stash)->xhv_name && HvENAME_HEK_NN(stash)
220 ? HvENAME_HEK_NN(stash)
221 : HvNAME_HEK(stash);
222
190d0b22 223 if (!stashhek)
1e05feb3 224 Perl_croak(aTHX_ "Can't linearize anonymous symbol table");
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225
226 if (level > 100)
227 Perl_croak(aTHX_ "Recursive inheritance detected in package '%s'",
190d0b22 228 HEK_KEY(stashhek));
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229
230 meta = HvMROMETA(stash);
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231
232 /* return cache if valid */
a3e6e81e 233 if((retval = MUTABLE_AV(MRO_GET_PRIVATE_DATA(meta, &dfs_alg)))) {
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234 return retval;
235 }
236
237 /* not in cache, make a new one */
1c908217 238
ad64d0ec 239 retval = MUTABLE_AV(sv_2mortal(MUTABLE_SV(newAV())));
a49ba3fc
NC
240 /* We use this later in this function, but don't need a reference to it
241 beyond the end of this function, so reference count is fine. */
242 our_name = newSVhek(stashhek);
243 av_push(retval, our_name); /* add ourselves at the top */
e1a479c5 244
1c908217 245 /* fetch our @ISA */
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246 gvp = (GV**)hv_fetchs(stash, "ISA", FALSE);
247 av = (gvp && (gv = *gvp) && isGV_with_GP(gv)) ? GvAV(gv) : NULL;
248
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NC
249 /* "stored" is used to keep track of all of the classnames we have added to
250 the MRO so far, so we can do a quick exists check and avoid adding
251 duplicate classnames to the MRO as we go.
252 It's then retained to be re-used as a fast lookup for ->isa(), by adding
253 our own name and "UNIVERSAL" to it. */
254
a49ba3fc 255 if(av && AvFILLp(av) >= 0) {
1c908217 256
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257 SV **svp = AvARRAY(av);
258 I32 items = AvFILLp(av) + 1;
1c908217
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259
260 /* foreach(@ISA) */
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261 while (items--) {
262 SV* const sv = *svp++;
263 HV* const basestash = gv_stashsv(sv, 0);
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264 SV *const *subrv_p;
265 I32 subrv_items;
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266
267 if (!basestash) {
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268 /* if no stash exists for this @ISA member,
269 simply add it to the MRO and move on */
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270 subrv_p = &sv;
271 subrv_items = 1;
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272 }
273 else {
1c908217 274 /* otherwise, recurse into ourselves for the MRO
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275 of this @ISA member, and append their MRO to ours.
276 The recursive call could throw an exception, which
277 has memory management implications here, hence the use of
278 the mortal. */
ffd8da72
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279 const AV *const subrv
280 = mro_get_linear_isa_dfs(basestash, level + 1);
281
282 subrv_p = AvARRAY(subrv);
283 subrv_items = AvFILLp(subrv) + 1;
284 }
73519bd0
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285 if (stored) {
286 while(subrv_items--) {
287 SV *const subsv = *subrv_p++;
288 /* LVALUE fetch will create a new undefined SV if necessary
289 */
290 HE *const he = hv_fetch_ent(stored, subsv, 1, 0);
291 assert(he);
292 if(HeVAL(he) != &PL_sv_undef) {
293 /* It was newly created. Steal it for our new SV, and
294 replace it in the hash with the "real" thing. */
295 SV *const val = HeVAL(he);
296 HEK *const key = HeKEY_hek(he);
297
298 HeVAL(he) = &PL_sv_undef;
299 /* Save copying by making a shared hash key scalar. We
300 inline this here rather than calling
301 Perl_newSVpvn_share because we already have the
302 scalar, and we already have the hash key. */
303 assert(SvTYPE(val) == SVt_NULL);
304 sv_upgrade(val, SVt_PV);
305 SvPV_set(val, HEK_KEY(share_hek_hek(key)));
306 SvCUR_set(val, HEK_LEN(key));
307 SvREADONLY_on(val);
308 SvFAKE_on(val);
309 SvPOK_on(val);
310 if (HEK_UTF8(key))
311 SvUTF8_on(val);
312
313 av_push(retval, val);
314 }
ffd8da72 315 }
73519bd0
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316 } else {
317 /* We are the first (or only) parent. We can short cut the
318 complexity above, because our @ISA is simply us prepended
319 to our parent's @ISA, and our ->isa cache is simply our
320 parent's, with our name added. */
321 /* newSVsv() is slow. This code is only faster if we can avoid
322 it by ensuring that SVs in the arrays are shared hash key
323 scalar SVs, because we can "copy" them very efficiently.
324 Although to be fair, we can't *ensure* this, as a reference
325 to the internal array is returned by mro::get_linear_isa(),
326 so we'll have to be defensive just in case someone faffed
327 with it. */
328 if (basestash) {
329 SV **svp;
17eef65c 330 stored = MUTABLE_HV(sv_2mortal((SV*)newHVhv(HvMROMETA(basestash)->isa)));
73519bd0
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331 av_extend(retval, subrv_items);
332 AvFILLp(retval) = subrv_items;
333 svp = AvARRAY(retval);
334 while(subrv_items--) {
335 SV *const val = *subrv_p++;
336 *++svp = SvIsCOW_shared_hash(val)
337 ? newSVhek(SvSHARED_HEK_FROM_PV(SvPVX(val)))
338 : newSVsv(val);
339 }
340 } else {
341 /* They have no stash. So create ourselves an ->isa cache
342 as if we'd copied it from what theirs should be. */
343 stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV())));
344 (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0);
345 av_push(retval,
346 newSVhek(HeKEY_hek(hv_store_ent(stored, sv,
347 &PL_sv_undef, 0))));
348 }
349 }
e1a479c5 350 }
73519bd0
NC
351 } else {
352 /* We have no parents. */
353 stored = MUTABLE_HV(sv_2mortal(MUTABLE_SV(newHV())));
354 (void) hv_store(stored, "UNIVERSAL", 9, &PL_sv_undef, 0);
e1a479c5
BB
355 }
356
ed09b296 357 (void) hv_store_ent(stored, our_name, &PL_sv_undef, 0);
ed09b296
NC
358
359 SvREFCNT_inc_simple_void_NN(stored);
360 SvTEMP_off(stored);
361 SvREADONLY_on(stored);
362
363 meta->isa = stored;
364
0fd7ece8
NC
365 /* now that we're past the exception dangers, grab our own reference to
366 the AV we're about to use for the result. The reference owned by the
367 mortals' stack will be released soon, so everything will balance. */
368 SvREFCNT_inc_simple_void_NN(retval);
369 SvTEMP_off(retval);
fdef73f9 370
1c908217
RGS
371 /* we don't want anyone modifying the cache entry but us,
372 and we do so by replacing it completely */
e1a479c5 373 SvREADONLY_on(retval);
1c908217 374
a3e6e81e 375 return MUTABLE_AV(Perl_mro_set_private_data(aTHX_ meta, &dfs_alg,
fa60396f 376 MUTABLE_SV(retval)));
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377}
378
379/*
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380=for apidoc mro_get_linear_isa
381
382Returns either C<mro_get_linear_isa_c3> or
383C<mro_get_linear_isa_dfs> for the given stash,
384dependant upon which MRO is in effect
385for that stash. The return value is a
386read-only AV*.
387
1c908217
RGS
388You are responsible for C<SvREFCNT_inc()> on the
389return value if you plan to store it anywhere
390semi-permanently (otherwise it might be deleted
391out from under you the next time the cache is
392invalidated).
393
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394=cut
395*/
396AV*
397Perl_mro_get_linear_isa(pTHX_ HV *stash)
398{
399 struct mro_meta* meta;
7311f41d 400 AV *isa;
2c7f4b87 401
7918f24d 402 PERL_ARGS_ASSERT_MRO_GET_LINEAR_ISA;
2c7f4b87
BB
403 if(!SvOOK(stash))
404 Perl_croak(aTHX_ "Can't linearize anonymous symbol table");
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405
406 meta = HvMROMETA(stash);
3d76853f 407 if (!meta->mro_which)
14f97ce6 408 Perl_croak(aTHX_ "panic: invalid MRO!");
7311f41d
FC
409 isa = meta->mro_which->resolve(aTHX_ stash, 0);
410
411 if (!meta->isa) {
412 HV *const isa_hash = newHV();
413 /* Linearisation didn't build it for us, so do it here. */
414 SV *const *svp = AvARRAY(isa);
415 SV *const *const svp_end = svp + AvFILLp(isa) + 1;
416 const HEK *canon_name = HvENAME_HEK(stash);
417 if (!canon_name) canon_name = HvNAME_HEK(stash);
418
419 while (svp < svp_end) {
420 (void) hv_store_ent(isa_hash, *svp++, &PL_sv_undef, 0);
421 }
422
423 (void) hv_common(isa_hash, NULL, HEK_KEY(canon_name),
424 HEK_LEN(canon_name), HEK_FLAGS(canon_name),
425 HV_FETCH_ISSTORE, &PL_sv_undef,
426 HEK_HASH(canon_name));
427 (void) hv_store(isa_hash, "UNIVERSAL", 9, &PL_sv_undef, 0);
428
429 SvREADONLY_on(isa_hash);
430
431 meta->isa = isa_hash;
432 }
433
434 return isa;
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435}
436
437/*
438=for apidoc mro_isa_changed_in
439
1c908217 440Takes the necessary steps (cache invalidations, mostly)
e1a479c5
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441when the @ISA of the given package has changed. Invoked
442by the C<setisa> magic, should not need to invoke directly.
443
6f86b615
FC
444=for apidoc mro_isa_changed_in3
445
446Takes the necessary steps (cache invalidations, mostly)
447when the @ISA of the given package has changed. Invoked
448by the C<setisa> magic, should not need to invoke directly.
449
450The stash can be passed as the first argument, or its name and length as
451the second and third (or both). If just the name is passed and the stash
452does not exist, then only the subclasses' method and isa caches will be
453invalidated.
454
e1a479c5
BB
455=cut
456*/
457void
6f86b615
FC
458Perl_mro_isa_changed_in3(pTHX_ HV* stash, const char *stashname,
459 STRLEN stashname_len)
e1a479c5
BB
460{
461 dVAR;
462 HV* isarev;
463 AV* linear_mro;
464 HE* iter;
465 SV** svp;
466 I32 items;
1e05feb3 467 bool is_universal;
6f86b615 468 struct mro_meta * meta = NULL;
80ebaca2 469 HV *isa = NULL;
e1a479c5 470
6f86b615 471 if(!stashname && stash) {
00169e2c
FC
472 stashname = HvENAME_get(stash);
473 stashname_len = HvENAMELEN_get(stash);
6f86b615
FC
474 }
475 else if(!stash)
476 stash = gv_stashpvn(stashname, stashname_len, 0 /* don't add */);
7918f24d 477
2c7f4b87
BB
478 if(!stashname)
479 Perl_croak(aTHX_ "Can't call mro_isa_changed_in() on anonymous symbol table");
480
6f86b615
FC
481 if(stash) {
482 /* wipe out the cached linearizations for this stash */
483 meta = HvMROMETA(stash);
484 if (meta->mro_linear_all) {
9953ff72
NC
485 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
486 meta->mro_linear_all = NULL;
553e831a 487 /* This is just acting as a shortcut pointer. */
3a6fa573 488 meta->mro_linear_current = NULL;
6f86b615 489 } else if (meta->mro_linear_current) {
553e831a 490 /* Only the current MRO is stored, so this owns the data. */
3a6fa573
NC
491 SvREFCNT_dec(meta->mro_linear_current);
492 meta->mro_linear_current = NULL;
6f86b615
FC
493 }
494 if (meta->isa) {
80ebaca2
FC
495 /* Steal it for our own purposes. */
496 isa = (HV *)sv_2mortal((SV *)meta->isa);
5782d502 497 meta->isa = NULL;
6f86b615 498 }
e1a479c5 499
6f86b615
FC
500 /* Inc the package generation, since our @ISA changed */
501 meta->pkg_gen++;
502 }
70cd14a1 503
e1a479c5
BB
504 /* Wipe the global method cache if this package
505 is UNIVERSAL or one of its parents */
dd69841b
BB
506
507 svp = hv_fetch(PL_isarev, stashname, stashname_len, 0);
85fbaab2 508 isarev = svp ? MUTABLE_HV(*svp) : NULL;
dd69841b
BB
509
510 if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL"))
511 || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) {
e1a479c5 512 PL_sub_generation++;
dd69841b
BB
513 is_universal = TRUE;
514 }
1e05feb3 515 else { /* Wipe the local method cache otherwise */
6f86b615 516 if(meta) meta->cache_gen++;
1e05feb3
AL
517 is_universal = FALSE;
518 }
e1a479c5
BB
519
520 /* wipe next::method cache too */
6f86b615 521 if(meta && meta->mro_nextmethod) hv_clear(meta->mro_nextmethod);
1e05feb3 522
e1a479c5 523 /* Iterate the isarev (classes that are our children),
80ebaca2
FC
524 wiping out their linearization, method and isa caches
525 and upating PL_isarev. */
dd69841b 526 if(isarev) {
80ebaca2
FC
527 HV *isa_hashes = NULL;
528
529 /* We have to iterate through isarev twice to avoid a chicken and
530 * egg problem: if A inherits from B and both are in isarev, A might
531 * be processed before B and use B’s previous linearisation.
532 */
533
534 /* First iteration: Wipe everything, but stash away the isa hashes
535 * since we still need them for updating PL_isarev.
536 */
537
538 if(hv_iterinit(isarev)) {
539 /* Only create the hash if we need it; i.e., if isarev has
540 any elements. */
541 isa_hashes = (HV *)sv_2mortal((SV *)newHV());
542 }
e1a479c5 543 while((iter = hv_iternext(isarev))) {
ec49eb61
NC
544 I32 len;
545 const char* const revkey = hv_iterkey(iter, &len);
546 HV* revstash = gv_stashpvn(revkey, len, 0);
bc2cbbac
BB
547 struct mro_meta* revmeta;
548
549 if(!revstash) continue;
550 revmeta = HvMROMETA(revstash);
9953ff72
NC
551 if (revmeta->mro_linear_all) {
552 SvREFCNT_dec(MUTABLE_SV(revmeta->mro_linear_all));
553 revmeta->mro_linear_all = NULL;
553e831a 554 /* This is just acting as a shortcut pointer. */
3a6fa573
NC
555 revmeta->mro_linear_current = NULL;
556 } else if (revmeta->mro_linear_current) {
553e831a 557 /* Only the current MRO is stored, so this owns the data. */
3a6fa573
NC
558 SvREFCNT_dec(revmeta->mro_linear_current);
559 revmeta->mro_linear_current = NULL;
553e831a 560 }
dd69841b
BB
561 if(!is_universal)
562 revmeta->cache_gen++;
e1a479c5
BB
563 if(revmeta->mro_nextmethod)
564 hv_clear(revmeta->mro_nextmethod);
80ebaca2
FC
565
566 (void)
567 hv_store(
568 isa_hashes, (const char*)&revstash, sizeof(HV *),
569 revmeta->isa ? (SV *)revmeta->isa : &PL_sv_undef, 0
570 );
571 revmeta->isa = NULL;
572 }
573
574 /* Second pass: Update PL_isarev. We can just use isa_hashes to
575 * avoid another round of stash lookups. */
576
577 /* isarev might be deleted from PL_isarev during this loop, so hang
578 * on to it. */
579 SvREFCNT_inc_simple_void_NN(sv_2mortal((SV *)isarev));
580
581 if(isa_hashes) {
582 hv_iterinit(isa_hashes);
583 while((iter = hv_iternext(isa_hashes))) {
584 HV* const revstash = *(HV **)HEK_KEY(HeKEY_hek(iter));
585 HV * const isa = (HV *)HeVAL(iter);
586 const HEK *namehek;
587
588 /* Re-calculate the linearisation, unless a previous iter-
589 ation was for a subclass of this class. */
590 if(!HvMROMETA(revstash)->isa)
591 (void)mro_get_linear_isa(revstash);
592
593 /* We're starting at the 2nd element, skipping revstash */
594 linear_mro = mro_get_linear_isa(revstash);
595 svp = AvARRAY(linear_mro) + 1;
596 items = AvFILLp(linear_mro);
597
598 namehek = HvENAME_HEK(revstash);
599 if (!namehek) namehek = HvNAME_HEK(revstash);
600
601 while (items--) {
602 SV* const sv = *svp++;
603 HV* mroisarev;
604
605 HE *he = hv_fetch_ent(PL_isarev, sv, TRUE, 0);
606
607 /* That fetch should not fail. But if it had to create
608 a new SV for us, then will need to upgrade it to an
609 HV (which sv_upgrade() can now do for us). */
610
611 mroisarev = MUTABLE_HV(HeVAL(he));
612
613 SvUPGRADE(MUTABLE_SV(mroisarev), SVt_PVHV);
614
615 /* This hash only ever contains PL_sv_yes. Storing it
616 over itself is almost as cheap as calling hv_exists,
617 so on aggregate we expect to save time by not making
618 two calls to the common HV code for the case where
619 it doesn't exist. */
620
621 (void)
622 hv_store(
623 mroisarev, HEK_KEY(namehek), HEK_LEN(namehek),
624 &PL_sv_yes, 0
625 );
626 }
627
628 if((SV *)isa != &PL_sv_undef)
629 mro_clean_isarev(
630 isa, HEK_KEY(namehek), HEK_LEN(namehek),
631 HvMROMETA(revstash)->isa
632 );
633 }
e1a479c5
BB
634 }
635 }
636
c9143745
FC
637 /* Now iterate our MRO (parents), adding ourselves and everything from
638 our isarev to their isarev.
1c908217
RGS
639 */
640
6f86b615 641 /* This only applies if the stash exists. */
80ebaca2 642 if(!stash) goto clean_up_isarev;
6f86b615 643
1c908217 644 /* We're starting at the 2nd element, skipping ourselves here */
e1a479c5
BB
645 linear_mro = mro_get_linear_isa(stash);
646 svp = AvARRAY(linear_mro) + 1;
647 items = AvFILLp(linear_mro);
1c908217 648
e1a479c5
BB
649 while (items--) {
650 SV* const sv = *svp++;
e1a479c5
BB
651 HV* mroisarev;
652
117b69ca
NC
653 HE *he = hv_fetch_ent(PL_isarev, sv, TRUE, 0);
654
655 /* That fetch should not fail. But if it had to create a new SV for
4ea50411
NC
656 us, then will need to upgrade it to an HV (which sv_upgrade() can
657 now do for us. */
117b69ca 658
85fbaab2 659 mroisarev = MUTABLE_HV(HeVAL(he));
e1a479c5 660
ad64d0ec 661 SvUPGRADE(MUTABLE_SV(mroisarev), SVt_PVHV);
117b69ca 662
25270bc0
NC
663 /* This hash only ever contains PL_sv_yes. Storing it over itself is
664 almost as cheap as calling hv_exists, so on aggregate we expect to
665 save time by not making two calls to the common HV code for the
666 case where it doesn't exist. */
667
04fe65b0 668 (void)hv_store(mroisarev, stashname, stashname_len, &PL_sv_yes, 0);
80ebaca2
FC
669 }
670
671 clean_up_isarev:
672 /* Delete our name from our former parents’ isarevs. */
673 if(isa && HvARRAY(isa))
674 mro_clean_isarev(isa, stashname, stashname_len, meta->isa);
675}
676
677/* Deletes name from all the isarev entries listed in isa */
678STATIC void
679S_mro_clean_isarev(pTHX_ HV * const isa, const char * const name,
680 const STRLEN len, HV * const exceptions)
681{
682 HE* iter;
e1a479c5 683
80ebaca2
FC
684 PERL_ARGS_ASSERT_MRO_CLEAN_ISAREV;
685
686 /* Delete our name from our former parents’ isarevs. */
687 if(isa && HvARRAY(isa) && hv_iterinit(isa)) {
688 SV **svp;
689 while((iter = hv_iternext(isa))) {
690 I32 klen;
691 const char * const key = hv_iterkey(iter, &klen);
692 if(exceptions && hv_exists(exceptions, key, klen)) continue;
693 svp = hv_fetch(PL_isarev, key, klen, 0);
694 if(svp) {
695 HV * const isarev = (HV *)*svp;
696 (void)hv_delete(isarev, name, len, G_DISCARD);
697 if(!HvARRAY(isarev) || !HvKEYS(isarev))
698 (void)hv_delete(PL_isarev, key, klen, G_DISCARD);
e1a479c5
BB
699 }
700 }
701 }
702}
703
704/*
c8bbf675
FC
705=for apidoc mro_package_moved
706
d056e33c
FC
707Call this function to signal to a stash that it has been assigned to
708another spot in the stash hierarchy. C<stash> is the stash that has been
709assigned. C<oldstash> is the stash it replaces, if any. C<gv> is the glob
710that is actually being assigned to. C<newname> and C<newname_len> are the
711full name of the GV. If these last two arguments are omitted, they can be
35759254 712inferred from C<gv>. C<gv> can be omitted if C<newname> is given.
d056e33c 713
35759254 714This can also be called with a null first argument to
d056e33c
FC
715indicate that C<oldstash> has been deleted.
716
717This function invalidates isa caches on the old stash, on all subpackages
718nested inside it, and on the subclasses of all those, including
719non-existent packages that have corresponding entries in C<stash>.
c8bbf675 720
80ebaca2
FC
721It also sets the effective names (C<HvENAME>) on all the stashes as
722appropriate.
723
c8bbf675
FC
724=cut
725*/
726void
35759254
FC
727Perl_mro_package_moved(pTHX_ HV * const stash, HV * const oldstash,
728 const GV *gv, const char *newname,
62c1e33f 729 I32 newname_len)
c8bbf675 730{
80ebaca2
FC
731 HV *stashes;
732 HE* iter;
62c1e33f 733
35759254 734 assert(stash || oldstash);
80ebaca2 735 assert(gv || newname);
35759254
FC
736
737 /* Determine the name of the location that stash was assigned to
738 * or from which oldstash was removed.
739 *
928eb066 740 * We cannot reliably use the name in oldstash, because it may have
35759254
FC
741 * been deleted from the location in the symbol table that its name
742 * suggests, as in this case:
743 *
744 * $globref = \*foo::bar::;
745 * Symbol::delete_package("foo");
746 * *$globref = \%baz::;
747 * *$globref = *frelp::;
748 * # calls mro_package_moved(%frelp::, %baz::, *$globref, NULL, 0)
749 *
750 * If newname is not null, then we trust that the caller gave us the
751 * right name. Otherwise, we get it from the gv. But if the gv is not
752 * in the symbol table, then we just return.
753 */
d056e33c
FC
754 if(!newname && gv) {
755 SV * const namesv = sv_newmortal();
62c1e33f 756 STRLEN len;
d056e33c 757 gv_fullname4(namesv, gv, NULL, 0);
35759254 758 if(gv_fetchsv(namesv, GV_NOADD_NOINIT, SVt_PVGV) != gv) return;
62c1e33f
FC
759 newname = SvPV_const(namesv, len);
760 newname_len = len - 2; /* skip trailing :: */
d056e33c 761 }
35759254 762 if(newname_len < 0) newname_len = -newname_len;
c8bbf675 763
80ebaca2
FC
764 /* Get a list of all the affected classes. */
765 /* We cannot simply pass them all to mro_isa_changed_in to avoid
766 the list, as that function assumes that only one package has
767 changed. It does not work with:
768
769 @foo::ISA = qw( B B::B );
770 *B:: = delete $::{"A::"};
771
772 as neither B nor B::B can be updated before the other, since they
773 will reset caches on foo, which will see either B or B::B with the
774 wrong name. The names must be set on *all* affected stashes before
775 we do anything else.
776 */
777 stashes = (HV *) sv_2mortal((SV *)newHV());
b89cdb22
FC
778 mro_gather_and_rename(
779 stashes, (HV *) sv_2mortal((SV *)newHV()),
780 stash, oldstash, newname, newname_len
781 );
80ebaca2
FC
782
783 /* Iterate through the stashes, wiping isa linearisations, but leaving
784 the isa hash (which mro_isa_changed_in needs for adjusting the
785 isarev hashes belonging to parent classes). */
786 hv_iterinit(stashes);
787 while((iter = hv_iternext(stashes))) {
788 if(HeVAL(iter) != &PL_sv_yes && HvENAME(HeVAL(iter))) {
789 struct mro_meta* meta;
790 meta = HvMROMETA((HV *)HeVAL(iter));
791 if (meta->mro_linear_all) {
792 SvREFCNT_dec(MUTABLE_SV(meta->mro_linear_all));
793 meta->mro_linear_all = NULL;
794 /* This is just acting as a shortcut pointer. */
795 meta->mro_linear_current = NULL;
796 } else if (meta->mro_linear_current) {
797 /* Only the current MRO is stored, so this owns the data. */
798 SvREFCNT_dec(meta->mro_linear_current);
799 meta->mro_linear_current = NULL;
800 }
801 }
802 }
803
804 /* Once the caches have been wiped on all the classes, call
805 mro_isa_changed_in on each. */
806 hv_iterinit(stashes);
807 while((iter = hv_iternext(stashes))) {
b89cdb22 808 if(HvENAME(HeVAL(iter)))
80ebaca2 809 mro_isa_changed_in((HV *)HeVAL(iter));
80ebaca2
FC
810 }
811}
812
813void
b89cdb22
FC
814S_mro_gather_and_rename(pTHX_ HV * const stashes, HV * const seen_stashes,
815 HV *stash, HV *oldstash, const char *name,
816 I32 namlen)
80ebaca2
FC
817{
818 register XPVHV* xhv;
819 register HE *entry;
820 I32 riter = -1;
821 const bool stash_had_name = stash && HvENAME(stash);
822 HV *seen = NULL;
823 HV *isarev = NULL;
824 SV **svp;
825
826 PERL_ARGS_ASSERT_MRO_GATHER_AND_RENAME;
827
b89cdb22
FC
828 /* We use the seen_stashes hash to keep track of which packages have
829 been encountered so far. This must be separate from the main list of
830 stashes, as we need to distinguish between stashes being assigned
831 and stashes being replaced/deleted. (A nested stash can be on both
832 sides of an assignment. We cannot simply skip iterating through a
833 stash on the right if we have seen it on the left, as it will not
834 get its ename assigned to it.)
835
836 To avoid allocating extra SVs, instead of a bitfield we can make
837 bizarre use of immortals:
838
839 &PL_sv_undef: seen on the left (oldstash)
840 &PL_sv_no : seen on the right (stash)
841 &PL_sv_yes : seen on both sides
842
843 */
844
80ebaca2
FC
845 if(oldstash) {
846 /* Add to the big list. */
847 HE * const entry
848 = (HE *)
849 hv_common(
b89cdb22 850 seen_stashes, NULL, (const char *)&oldstash, sizeof(HV *), 0,
df5f182b 851 HV_FETCH_LVALUE|HV_FETCH_EMPTY_HE, NULL, 0
80ebaca2 852 );
b89cdb22 853 if(HeVAL(entry) == &PL_sv_undef || HeVAL(entry) == &PL_sv_yes) {
80ebaca2
FC
854 oldstash = NULL;
855 goto check_stash;
856 }
b89cdb22
FC
857 HeVAL(entry)
858 = HeVAL(entry) == &PL_sv_no ? &PL_sv_yes : &PL_sv_undef;
859 (void)
860 hv_store(
861 stashes, (const char *)&oldstash, sizeof(HV *),
862 SvREFCNT_inc_simple_NN((SV*)oldstash), 0
863 );
80ebaca2
FC
864
865 /* Update the effective name. */
866 if(HvENAME_get(oldstash)) {
867 const HEK * const enamehek = HvENAME_HEK(oldstash);
868 if(PL_stashcache)
d7fbb1de 869 (void)
80ebaca2
FC
870 hv_delete(PL_stashcache, name, namlen, G_DISCARD);
871 hv_ename_delete(oldstash, name, namlen);
872
873 /* If the name deletion caused a name change, then we are not
874 * going to call mro_isa_changed_in with this name (and not at all
875 * if it has become anonymous) so we need to delete old isarev
876 * entries here, both those in the superclasses and this class’s
877 * own list of subclasses. We simply delete the latter from
878 * from PL_isarev, since we still need it. hv_delete mortifies it
879 * for us, so sv_2mortal is not necessary. */
880 if(HvENAME_HEK(oldstash) != enamehek) {
881 const struct mro_meta * meta = HvMROMETA(oldstash);
882 if(meta->isa && HvARRAY(meta->isa))
883 mro_clean_isarev(meta->isa, name, namlen, NULL);
884 isarev = (HV *)hv_delete(PL_isarev, name, namlen, 0);
885 }
886 }
d7fbb1de 887 }
80ebaca2 888 check_stash:
8b9e80a3 889 if(stash) {
80ebaca2
FC
890 hv_ename_add(stash, name, namlen);
891
b89cdb22
FC
892 /* Add it to the big list if it needs
893 * mro_isa_changed_in called on it. That happens if it was
80ebaca2
FC
894 * detached from the symbol table (so it had no HvENAME) before
895 * being assigned to the spot named by the ‘name’ variable, because
896 * its cached isa linerisation is now stale (the effective name
897 * having changed), and subclasses will then use that cache when
898 * mro_package_moved calls mro_isa_changed_in. (See
8b9e80a3 899 * [perl #77358].)
80ebaca2 900 *
8b9e80a3 901 * If it did have a name, then its previous name is still
80ebaca2
FC
902 * used in isa caches, and there is no need for
903 * mro_package_moved to call mro_isa_changed_in.
8b9e80a3 904 */
80ebaca2
FC
905
906 entry
907 = (HE *)
908 hv_common(
b89cdb22 909 seen_stashes, NULL, (const char *)&stash, sizeof(HV *), 0,
df5f182b 910 HV_FETCH_LVALUE|HV_FETCH_EMPTY_HE, NULL, 0
80ebaca2 911 );
b89cdb22 912 if(HeVAL(entry) == &PL_sv_yes || HeVAL(entry) == &PL_sv_no)
80ebaca2 913 stash = NULL;
b89cdb22
FC
914 else {
915 HeVAL(entry)
916 = HeVAL(entry) == &PL_sv_undef ? &PL_sv_yes : &PL_sv_no;
917 if(!stash_had_name)
918 (void)
919 hv_store(
920 stashes, (const char *)&stash, sizeof(HV *),
921 SvREFCNT_inc_simple_NN((SV *)stash), 0
922 );
923 }
8b9e80a3 924 }
d7fbb1de 925
80ebaca2
FC
926 if(!stash && !oldstash)
927 /* Both stashes have been encountered already. */
928 return;
929
930 /* Add all the subclasses to the big list. */
931 if(
932 isarev
933 || (
934 (svp = hv_fetch(PL_isarev, name, namlen, 0))
935 && (isarev = MUTABLE_HV(*svp))
936 )
937 ) {
938 HE *iter;
939 hv_iterinit(isarev);
940 while((iter = hv_iternext(isarev))) {
941 I32 len;
942 const char* const revkey = hv_iterkey(iter, &len);
943 HV* revstash = gv_stashpvn(revkey, len, 0);
944
945 if(!revstash) continue;
b89cdb22
FC
946 (void)
947 hv_store(
948 stashes, (const char *)&revstash, sizeof(HV *),
949 SvREFCNT_inc_simple_NN((SV *)revstash), 0
950 );
80ebaca2
FC
951 }
952 }
d056e33c
FC
953
954 if(
955 (!stash || !HvARRAY(stash)) && (!oldstash || !HvARRAY(oldstash))
d7fbb1de 956 ) return;
c8bbf675
FC
957
958 /* This is partly based on code in hv_iternext_flags. We are not call-
959 ing that here, as we want to avoid resetting the hash iterator. */
960
d056e33c
FC
961 /* Skip the entire loop if the hash is empty. */
962 if(oldstash && HvUSEDKEYS(oldstash)) {
963 xhv = (XPVHV*)SvANY(oldstash);
dbe2fffc 964 seen = (HV *) sv_2mortal((SV *)newHV());
d056e33c 965
80ebaca2
FC
966 /* Iterate through entries in the oldstash, adding them to the
967 list, meanwhile doing the equivalent of $seen{$key} = 1.
d056e33c
FC
968 */
969
970 while (++riter <= (I32)xhv->xhv_max) {
971 entry = (HvARRAY(oldstash))[riter];
972
973 /* Iterate through the entries in this list */
974 for(; entry; entry = HeNEXT(entry)) {
975 const char* key;
976 I32 len;
977
978 /* If this entry is not a glob, ignore it.
979 Try the next. */
980 if (!isGV(HeVAL(entry))) continue;
981
982 key = hv_iterkey(entry, &len);
983 if(len > 1 && key[len-2] == ':' && key[len-1] == ':') {
984 HV * const oldsubstash = GvHV(HeVAL(entry));
985 SV ** const stashentry
986 = stash ? hv_fetch(stash, key, len, 0) : NULL;
35759254 987 HV *substash = NULL;
62c1e33f
FC
988
989 /* Avoid main::main::main::... */
990 if(oldsubstash == oldstash) continue;
991
d056e33c 992 if(
35759254
FC
993 (
994 stashentry && *stashentry
995 && (substash = GvHV(*stashentry))
996 )
00169e2c 997 || (oldsubstash && HvENAME_get(oldsubstash))
d056e33c 998 )
35759254
FC
999 {
1000 /* Add :: and the key (minus the trailing ::)
1001 to newname. */
1002 SV *namesv
80ebaca2
FC
1003 = newSVpvn_flags(name, namlen, SVs_TEMP);
1004 {
1005 const char *name;
1006 STRLEN namlen;
1007 sv_catpvs(namesv, "::");
1008 sv_catpvn(namesv, key, len-2);
1009 name = SvPV_const(namesv, namlen);
1010 mro_gather_and_rename(
b89cdb22
FC
1011 stashes, seen_stashes,
1012 substash, oldsubstash, name, namlen
80ebaca2
FC
1013 );
1014 }
35759254 1015 }
d056e33c
FC
1016
1017 (void)hv_store(seen, key, len, &PL_sv_yes, 0);
1018 }
1019 }
1020 }
1021 }
c8bbf675
FC
1022
1023 /* Skip the entire loop if the hash is empty. */
d056e33c
FC
1024 if (stash && HvUSEDKEYS(stash)) {
1025 xhv = (XPVHV*)SvANY(stash);
b89cdb22 1026 riter = -1;
d056e33c
FC
1027
1028 /* Iterate through the new stash, skipping $seen{$key} items,
b89cdb22 1029 calling mro_gather_and_rename(stashes,seen,entry,NULL, ...). */
c8bbf675
FC
1030 while (++riter <= (I32)xhv->xhv_max) {
1031 entry = (HvARRAY(stash))[riter];
1032
1033 /* Iterate through the entries in this list */
1034 for(; entry; entry = HeNEXT(entry)) {
1035 const char* key;
1036 I32 len;
1037
1038 /* If this entry is not a glob, ignore it.
1039 Try the next. */
1040 if (!isGV(HeVAL(entry))) continue;
1041
1042 key = hv_iterkey(entry, &len);
1043 if(len > 1 && key[len-2] == ':' && key[len-1] == ':') {
d056e33c
FC
1044 HV *substash;
1045
1046 /* If this entry was seen when we iterated through the
1047 oldstash, skip it. */
1048 if(seen && hv_exists(seen, key, len)) continue;
1049
1050 /* We get here only if this stash has no corresponding
1051 entry in the stash being replaced. */
1052
1053 substash = GvHV(HeVAL(entry));
35759254 1054 if(substash) {
62c1e33f 1055 SV *namesv;
80ebaca2
FC
1056 const char *subname;
1057 STRLEN subnamlen;
62c1e33f
FC
1058
1059 /* Avoid checking main::main::main::... */
1060 if(substash == stash) continue;
1061
d056e33c
FC
1062 /* Add :: and the key (minus the trailing ::)
1063 to newname. */
62c1e33f 1064 namesv
80ebaca2 1065 = newSVpvn_flags(name, namlen, SVs_TEMP);
d056e33c
FC
1066 sv_catpvs(namesv, "::");
1067 sv_catpvn(namesv, key, len-2);
80ebaca2
FC
1068 subname = SvPV_const(namesv, subnamlen);
1069 mro_gather_and_rename(
b89cdb22
FC
1070 stashes, seen_stashes,
1071 substash, NULL, subname, subnamlen
d056e33c
FC
1072 );
1073 }
c8bbf675
FC
1074 }
1075 }
1076 }
1077 }
1078}
1079
1080/*
e1a479c5
BB
1081=for apidoc mro_method_changed_in
1082
47c9dd14
BB
1083Invalidates method caching on any child classes
1084of the given stash, so that they might notice
1085the changes in this one.
e1a479c5
BB
1086
1087Ideally, all instances of C<PL_sub_generation++> in
dd69841b
BB
1088perl source outside of C<mro.c> should be
1089replaced by calls to this.
1090
1091Perl automatically handles most of the common
1092ways a method might be redefined. However, there
1093are a few ways you could change a method in a stash
1094without the cache code noticing, in which case you
1095need to call this method afterwards:
e1a479c5 1096
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10971) Directly manipulating the stash HV entries from
1098XS code.
e1a479c5 1099
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11002) Assigning a reference to a readonly scalar
1101constant into a stash entry in order to create
1102a constant subroutine (like constant.pm
1103does).
1104
1105This same method is available from pure perl
1106via, C<mro::method_changed_in(classname)>.
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1107
1108=cut
1109*/
1110void
1111Perl_mro_method_changed_in(pTHX_ HV *stash)
1112{
00169e2c
FC
1113 const char * const stashname = HvENAME_get(stash);
1114 const STRLEN stashname_len = HvENAMELEN_get(stash);
dd69841b 1115
1e05feb3 1116 SV ** const svp = hv_fetch(PL_isarev, stashname, stashname_len, 0);
85fbaab2 1117 HV * const isarev = svp ? MUTABLE_HV(*svp) : NULL;
e1a479c5 1118
7918f24d
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1119 PERL_ARGS_ASSERT_MRO_METHOD_CHANGED_IN;
1120
2c7f4b87
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1121 if(!stashname)
1122 Perl_croak(aTHX_ "Can't call mro_method_changed_in() on anonymous symbol table");
1123
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1124 /* Inc the package generation, since a local method changed */
1125 HvMROMETA(stash)->pkg_gen++;
1126
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1127 /* If stash is UNIVERSAL, or one of UNIVERSAL's parents,
1128 invalidate all method caches globally */
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1129 if((stashname_len == 9 && strEQ(stashname, "UNIVERSAL"))
1130 || (isarev && hv_exists(isarev, "UNIVERSAL", 9))) {
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1131 PL_sub_generation++;
1132 return;
1133 }
1134
1135 /* else, invalidate the method caches of all child classes,
1136 but not itself */
dd69841b 1137 if(isarev) {
1e05feb3
AL
1138 HE* iter;
1139
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1140 hv_iterinit(isarev);
1141 while((iter = hv_iternext(isarev))) {
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1142 I32 len;
1143 const char* const revkey = hv_iterkey(iter, &len);
1144 HV* const revstash = gv_stashpvn(revkey, len, 0);
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BB
1145 struct mro_meta* mrometa;
1146
1147 if(!revstash) continue;
1148 mrometa = HvMROMETA(revstash);
dd69841b 1149 mrometa->cache_gen++;
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1150 if(mrometa->mro_nextmethod)
1151 hv_clear(mrometa->mro_nextmethod);
1152 }
1153 }
1154}
1155
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1156void
1157Perl_mro_set_mro(pTHX_ struct mro_meta *const meta, SV *const name)
1158{
1159 const struct mro_alg *const which = Perl_mro_get_from_name(aTHX_ name);
1160
1161 PERL_ARGS_ASSERT_MRO_SET_MRO;
1162
1163 if (!which)
1164 Perl_croak(aTHX_ "Invalid mro name: '%"SVf"'", name);
1165
1166 if(meta->mro_which != which) {
9953ff72 1167 if (meta->mro_linear_current && !meta->mro_linear_all) {
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NC
1168 /* If we were storing something directly, put it in the hash before
1169 we lose it. */
1170 Perl_mro_set_private_data(aTHX_ meta, meta->mro_which,
3a6fa573 1171 MUTABLE_SV(meta->mro_linear_current));
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1172 }
1173 meta->mro_which = which;
1174 /* Scrub our cached pointer to the private data. */
3a6fa573 1175 meta->mro_linear_current = NULL;
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1176 /* Only affects local method cache, not
1177 even child classes */
1178 meta->cache_gen++;
1179 if(meta->mro_nextmethod)
1180 hv_clear(meta->mro_nextmethod);
1181 }
1182}
1183
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1184#include "XSUB.h"
1185
e1a479c5 1186XS(XS_mro_method_changed_in);
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1187
1188void
1189Perl_boot_core_mro(pTHX)
1190{
1191 dVAR;
1192 static const char file[] = __FILE__;
1193
a3e6e81e 1194 Perl_mro_register(aTHX_ &dfs_alg);
a3e6e81e 1195
e1a479c5 1196 newXSproto("mro::method_changed_in", XS_mro_method_changed_in, file, "$");
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1197}
1198
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1199XS(XS_mro_method_changed_in)
1200{
1201 dVAR;
1202 dXSARGS;
1203 SV* classname;
1204 HV* class_stash;
1205
e1a479c5 1206 if(items != 1)
afa74d42 1207 croak_xs_usage(cv, "classname");
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1208
1209 classname = ST(0);
1210
1211 class_stash = gv_stashsv(classname, 0);
1212 if(!class_stash) Perl_croak(aTHX_ "No such class: '%"SVf"'!", SVfARG(classname));
1213
1214 mro_method_changed_in(class_stash);
1215
1216 XSRETURN_EMPTY;
1217}
1218
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1219/*
1220 * Local variables:
1221 * c-indentation-style: bsd
1222 * c-basic-offset: 4
1223 * indent-tabs-mode: t
1224 * End:
1225 *
1226 * ex: set ts=8 sts=4 sw=4 noet:
1227 */