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3f98fbb3 RGS |
1 | -*- buffer-read-only: t -*- |
2 | ||
3 | !!!!!!! DO NOT EDIT THIS FILE !!!!!!! | |
4 | This file is built by autodoc.pl extracting documentation from the C source | |
5 | files. | |
6 | ||
954c1994 GS |
7 | =head1 NAME |
8 | ||
1c846c1f | 9 | perlintern - autogenerated documentation of purely B<internal> |
954c1994 GS |
10 | Perl functions |
11 | ||
12 | =head1 DESCRIPTION | |
d8c40edc | 13 | X<internal Perl functions> X<interpreter functions> |
954c1994 | 14 | |
1c846c1f | 15 | This file is the autogenerated documentation of functions in the |
4375e838 | 16 | Perl interpreter that are documented using Perl's internal documentation |
1c846c1f | 17 | format but are not marked as part of the Perl API. In other words, |
954c1994 GS |
18 | B<they are not for use in extensions>! |
19 | ||
a8586c98 | 20 | |
7dafbf52 DM |
21 | =head1 CV reference counts and CvOUTSIDE |
22 | ||
23 | =over 8 | |
24 | ||
25 | =item CvWEAKOUTSIDE | |
d8c40edc | 26 | X<CvWEAKOUTSIDE> |
7dafbf52 DM |
27 | |
28 | Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing | |
29 | CV (if any). Because pointers to anonymous sub prototypes are | |
30 | stored in C<&> pad slots, it is a possible to get a circular reference, | |
31 | with the parent pointing to the child and vice-versa. To avoid the | |
32 | ensuing memory leak, we do not increment the reference count of the CV | |
33 | pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent | |
34 | has a C<&> pad slot pointing back to us. In this case, we set the | |
35 | C<CvWEAKOUTSIDE> flag in the child. This allows us to determine under what | |
36 | circumstances we should decrement the refcount of the parent when freeing | |
37 | the child. | |
38 | ||
28a5cf3b | 39 | There is a further complication with non-closure anonymous subs (i.e. those |
7dafbf52 DM |
40 | that do not refer to any lexicals outside that sub). In this case, the |
41 | anonymous prototype is shared rather than being cloned. This has the | |
42 | consequence that the parent may be freed while there are still active | |
43 | children, eg | |
44 | ||
45 | BEGIN { $a = sub { eval '$x' } } | |
46 | ||
47 | In this case, the BEGIN is freed immediately after execution since there | |
48 | are no active references to it: the anon sub prototype has | |
49 | C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same | |
50 | CV, so it doesn't contribute to BEGIN's refcount either. When $a is | |
51 | executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed, | |
52 | and the freed BEGIN is accessed. | |
53 | ||
54 | To avoid this, whenever a CV and its associated pad is freed, any | |
55 | C<&> entries in the pad are explicitly removed from the pad, and if the | |
56 | refcount of the pointed-to anon sub is still positive, then that | |
57 | child's C<CvOUTSIDE> is set to point to its grandparent. This will only | |
58 | occur in the single specific case of a non-closure anon prototype | |
59 | having one or more active references (such as C<$a> above). | |
60 | ||
61 | One other thing to consider is that a CV may be merely undefined | |
62 | rather than freed, eg C<undef &foo>. In this case, its refcount may | |
63 | not have reached zero, but we still delete its pad and its C<CvROOT> etc. | |
64 | Since various children may still have their C<CvOUTSIDE> pointing at this | |
65 | undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that | |
66 | the chain of lexical scopes is unbroken. For example, the following | |
67 | should print 123: | |
68 | ||
69 | my $x = 123; | |
70 | sub tmp { sub { eval '$x' } } | |
71 | my $a = tmp(); | |
72 | undef &tmp; | |
73 | print $a->(); | |
74 | ||
75 | bool CvWEAKOUTSIDE(CV *cv) | |
76 | ||
77 | =for hackers | |
78 | Found in file cv.h | |
79 | ||
80 | ||
81 | =back | |
82 | ||
dd2155a4 DM |
83 | =head1 Functions in file pad.h |
84 | ||
85 | ||
86 | =over 8 | |
87 | ||
88 | =item CX_CURPAD_SAVE | |
d8c40edc | 89 | X<CX_CURPAD_SAVE> |
dd2155a4 DM |
90 | |
91 | Save the current pad in the given context block structure. | |
92 | ||
93 | void CX_CURPAD_SAVE(struct context) | |
94 | ||
95 | =for hackers | |
96 | Found in file pad.h | |
97 | ||
98 | =item CX_CURPAD_SV | |
d8c40edc | 99 | X<CX_CURPAD_SV> |
dd2155a4 DM |
100 | |
101 | Access the SV at offset po in the saved current pad in the given | |
102 | context block structure (can be used as an lvalue). | |
103 | ||
f3548bdc | 104 | SV * CX_CURPAD_SV(struct context, PADOFFSET po) |
dd2155a4 DM |
105 | |
106 | =for hackers | |
107 | Found in file pad.h | |
108 | ||
d8c40edc AT |
109 | =item PAD_BASE_SV |
110 | X<PAD_BASE_SV> | |
dd2155a4 DM |
111 | |
112 | Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist | |
113 | ||
d8c40edc | 114 | SV * PAD_BASE_SV(PADLIST padlist, PADOFFSET po) |
dd2155a4 DM |
115 | |
116 | =for hackers | |
117 | Found in file pad.h | |
118 | ||
119 | =item PAD_CLONE_VARS | |
d8c40edc | 120 | X<PAD_CLONE_VARS> |
dd2155a4 | 121 | |
dd2155a4 DM |
122 | Clone the state variables associated with running and compiling pads. |
123 | ||
d77cdebf | 124 | void PAD_CLONE_VARS(PerlInterpreter *proto_perl, CLONE_PARAMS* param) |
dd2155a4 DM |
125 | |
126 | =for hackers | |
127 | Found in file pad.h | |
128 | ||
129 | =item PAD_COMPNAME_FLAGS | |
d8c40edc | 130 | X<PAD_COMPNAME_FLAGS> |
dd2155a4 DM |
131 | |
132 | Return the flags for the current compiling pad name | |
133 | at offset C<po>. Assumes a valid slot entry. | |
134 | ||
135 | U32 PAD_COMPNAME_FLAGS(PADOFFSET po) | |
136 | ||
137 | =for hackers | |
138 | Found in file pad.h | |
139 | ||
140 | =item PAD_COMPNAME_GEN | |
d8c40edc | 141 | X<PAD_COMPNAME_GEN> |
dd2155a4 DM |
142 | |
143 | The generation number of the name at offset C<po> in the current | |
00a0d662 | 144 | compiling pad (lvalue). Note that C<SvUVX> is hijacked for this purpose. |
dd2155a4 DM |
145 | |
146 | STRLEN PAD_COMPNAME_GEN(PADOFFSET po) | |
147 | ||
148 | =for hackers | |
149 | Found in file pad.h | |
150 | ||
27da23d5 | 151 | =item PAD_COMPNAME_GEN_set |
d8c40edc | 152 | X<PAD_COMPNAME_GEN_set> |
27da23d5 JH |
153 | |
154 | Sets the generation number of the name at offset C<po> in the current | |
00a0d662 | 155 | ling pad (lvalue) to C<gen>. Note that C<SvUV_set> is hijacked for this purpose. |
27da23d5 JH |
156 | |
157 | STRLEN PAD_COMPNAME_GEN_set(PADOFFSET po, int gen) | |
158 | ||
159 | =for hackers | |
160 | Found in file pad.h | |
161 | ||
dd2155a4 | 162 | =item PAD_COMPNAME_OURSTASH |
d8c40edc | 163 | X<PAD_COMPNAME_OURSTASH> |
dd2155a4 DM |
164 | |
165 | Return the stash associated with an C<our> variable. | |
166 | Assumes the slot entry is a valid C<our> lexical. | |
167 | ||
168 | HV * PAD_COMPNAME_OURSTASH(PADOFFSET po) | |
169 | ||
170 | =for hackers | |
171 | Found in file pad.h | |
172 | ||
173 | =item PAD_COMPNAME_PV | |
d8c40edc | 174 | X<PAD_COMPNAME_PV> |
dd2155a4 DM |
175 | |
176 | Return the name of the current compiling pad name | |
177 | at offset C<po>. Assumes a valid slot entry. | |
178 | ||
179 | char * PAD_COMPNAME_PV(PADOFFSET po) | |
180 | ||
181 | =for hackers | |
182 | Found in file pad.h | |
183 | ||
184 | =item PAD_COMPNAME_TYPE | |
d8c40edc | 185 | X<PAD_COMPNAME_TYPE> |
dd2155a4 DM |
186 | |
187 | Return the type (stash) of the current compiling pad name at offset | |
188 | C<po>. Must be a valid name. Returns null if not typed. | |
189 | ||
190 | HV * PAD_COMPNAME_TYPE(PADOFFSET po) | |
191 | ||
192 | =for hackers | |
193 | Found in file pad.h | |
194 | ||
195 | =item PAD_DUP | |
d8c40edc | 196 | X<PAD_DUP> |
dd2155a4 DM |
197 | |
198 | Clone a padlist. | |
199 | ||
200 | void PAD_DUP(PADLIST dstpad, PADLIST srcpad, CLONE_PARAMS* param) | |
201 | ||
202 | =for hackers | |
203 | Found in file pad.h | |
204 | ||
f3548bdc | 205 | =item PAD_RESTORE_LOCAL |
d8c40edc | 206 | X<PAD_RESTORE_LOCAL> |
f3548bdc DM |
207 | |
208 | Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL() | |
209 | ||
210 | void PAD_RESTORE_LOCAL(PAD *opad) | |
211 | ||
212 | =for hackers | |
213 | Found in file pad.h | |
214 | ||
215 | =item PAD_SAVE_LOCAL | |
d8c40edc | 216 | X<PAD_SAVE_LOCAL> |
f3548bdc DM |
217 | |
218 | Save the current pad to the local variable opad, then make the | |
219 | current pad equal to npad | |
220 | ||
221 | void PAD_SAVE_LOCAL(PAD *opad, PAD *npad) | |
222 | ||
223 | =for hackers | |
224 | Found in file pad.h | |
225 | ||
dd2155a4 | 226 | =item PAD_SAVE_SETNULLPAD |
d8c40edc | 227 | X<PAD_SAVE_SETNULLPAD> |
dd2155a4 DM |
228 | |
229 | Save the current pad then set it to null. | |
230 | ||
231 | void PAD_SAVE_SETNULLPAD() | |
232 | ||
233 | =for hackers | |
234 | Found in file pad.h | |
235 | ||
d8c40edc AT |
236 | =item PAD_SETSV |
237 | X<PAD_SETSV> | |
dd2155a4 DM |
238 | |
239 | Set the slot at offset C<po> in the current pad to C<sv> | |
240 | ||
d8c40edc | 241 | SV * PAD_SETSV(PADOFFSET po, SV* sv) |
dd2155a4 DM |
242 | |
243 | =for hackers | |
244 | Found in file pad.h | |
245 | ||
d8c40edc AT |
246 | =item PAD_SET_CUR |
247 | X<PAD_SET_CUR> | |
dd2155a4 DM |
248 | |
249 | Set the current pad to be pad C<n> in the padlist, saving | |
f54ba1c2 DM |
250 | the previous current pad. NB currently this macro expands to a string too |
251 | long for some compilers, so it's best to replace it with | |
252 | ||
253 | SAVECOMPPAD(); | |
254 | PAD_SET_CUR_NOSAVE(padlist,n); | |
255 | ||
dd2155a4 | 256 | |
d8c40edc | 257 | void PAD_SET_CUR(PADLIST padlist, I32 n) |
dd2155a4 DM |
258 | |
259 | =for hackers | |
260 | Found in file pad.h | |
261 | ||
d8c40edc AT |
262 | =item PAD_SET_CUR_NOSAVE |
263 | X<PAD_SET_CUR_NOSAVE> | |
bf9cdc68 RG |
264 | |
265 | like PAD_SET_CUR, but without the save | |
266 | ||
d8c40edc | 267 | void PAD_SET_CUR_NOSAVE(PADLIST padlist, I32 n) |
bf9cdc68 RG |
268 | |
269 | =for hackers | |
270 | Found in file pad.h | |
271 | ||
d8c40edc AT |
272 | =item PAD_SV |
273 | X<PAD_SV> | |
dd2155a4 DM |
274 | |
275 | Get the value at offset C<po> in the current pad | |
276 | ||
d8c40edc | 277 | void PAD_SV(PADOFFSET po) |
dd2155a4 DM |
278 | |
279 | =for hackers | |
280 | Found in file pad.h | |
281 | ||
d8c40edc AT |
282 | =item PAD_SVl |
283 | X<PAD_SVl> | |
dd2155a4 DM |
284 | |
285 | Lightweight and lvalue version of C<PAD_SV>. | |
286 | Get or set the value at offset C<po> in the current pad. | |
287 | Unlike C<PAD_SV>, does not print diagnostics with -DX. | |
288 | For internal use only. | |
289 | ||
d8c40edc | 290 | SV * PAD_SVl(PADOFFSET po) |
dd2155a4 DM |
291 | |
292 | =for hackers | |
293 | Found in file pad.h | |
294 | ||
d8c40edc AT |
295 | =item SAVECLEARSV |
296 | X<SAVECLEARSV> | |
dd2155a4 | 297 | |
28a5cf3b | 298 | Clear the pointed to pad value on scope exit. (i.e. the runtime action of 'my') |
dd2155a4 | 299 | |
d8c40edc | 300 | void SAVECLEARSV(SV **svp) |
dd2155a4 DM |
301 | |
302 | =for hackers | |
303 | Found in file pad.h | |
304 | ||
305 | =item SAVECOMPPAD | |
d8c40edc | 306 | X<SAVECOMPPAD> |
dd2155a4 DM |
307 | |
308 | save PL_comppad and PL_curpad | |
309 | ||
dd2155a4 | 310 | |
dd2155a4 DM |
311 | |
312 | ||
313 | ||
f3548bdc | 314 | void SAVECOMPPAD() |
dd2155a4 DM |
315 | |
316 | =for hackers | |
317 | Found in file pad.h | |
318 | ||
d8c40edc AT |
319 | =item SAVEPADSV |
320 | X<SAVEPADSV> | |
dd2155a4 DM |
321 | |
322 | Save a pad slot (used to restore after an iteration) | |
323 | ||
f3548bdc | 324 | XXX DAPM it would make more sense to make the arg a PADOFFSET |
d8c40edc | 325 | void SAVEPADSV(PADOFFSET po) |
dd2155a4 DM |
326 | |
327 | =for hackers | |
328 | Found in file pad.h | |
329 | ||
330 | ||
331 | =back | |
332 | ||
a4f1a029 NIS |
333 | =head1 GV Functions |
334 | ||
335 | =over 8 | |
336 | ||
337 | =item is_gv_magical | |
d8c40edc | 338 | X<is_gv_magical> |
a4f1a029 NIS |
339 | |
340 | Returns C<TRUE> if given the name of a magical GV. | |
341 | ||
342 | Currently only useful internally when determining if a GV should be | |
343 | created even in rvalue contexts. | |
344 | ||
345 | C<flags> is not used at present but available for future extension to | |
346 | allow selecting particular classes of magical variable. | |
347 | ||
766f8916 MHM |
348 | Currently assumes that C<name> is NUL terminated (as well as len being valid). |
349 | This assumption is met by all callers within the perl core, which all pass | |
350 | pointers returned by SvPV. | |
351 | ||
7fc63493 AL |
352 | bool is_gv_magical(const char *name, STRLEN len, U32 flags) |
353 | ||
354 | =for hackers | |
355 | Found in file gv.c | |
356 | ||
357 | =item is_gv_magical_sv | |
d8c40edc | 358 | X<is_gv_magical_sv> |
7fc63493 AL |
359 | |
360 | Returns C<TRUE> if given the name of a magical GV. Calls is_gv_magical. | |
361 | ||
362 | bool is_gv_magical_sv(SV *name, U32 flags) | |
645c22ef DM |
363 | |
364 | =for hackers | |
a4f1a029 NIS |
365 | Found in file gv.c |
366 | ||
367 | ||
368 | =back | |
369 | ||
b3ca2e83 NC |
370 | =head1 Hash Manipulation Functions |
371 | ||
372 | =over 8 | |
373 | ||
bd95ae50 SH |
374 | =item refcounted_he_chain_2hv |
375 | X<refcounted_he_chain_2hv> | |
376 | ||
8a0be661 | 377 | Generates and returns a C<HV *> by walking up the tree starting at the passed |
bd95ae50 SH |
378 | in C<struct refcounted_he *>. |
379 | ||
380 | HV * refcounted_he_chain_2hv(const struct refcounted_he *c) | |
381 | ||
382 | =for hackers | |
383 | Found in file hv.c | |
384 | ||
b3ca2e83 NC |
385 | =item refcounted_he_free |
386 | X<refcounted_he_free> | |
387 | ||
388 | Decrements the reference count of the passed in C<struct refcounted_he *> | |
389 | by one. If the reference count reaches zero the structure's memory is freed, | |
390 | and C<refcounted_he_free> iterates onto the parent node. | |
391 | ||
392 | void refcounted_he_free(struct refcounted_he *he) | |
393 | ||
394 | =for hackers | |
395 | Found in file hv.c | |
396 | ||
397 | =item refcounted_he_new | |
398 | X<refcounted_he_new> | |
399 | ||
ec2a1de7 NC |
400 | Creates a new C<struct refcounted_he>. As S<key> is copied, and value is |
401 | stored in a compact form, all references remain the property of the caller. | |
402 | The C<struct refcounted_he> is returned with a reference count of 1. | |
b3ca2e83 | 403 | |
b46c265e | 404 | struct refcounted_he * refcounted_he_new(struct refcounted_he *const parent, SV *const key, SV *const value) |
b3ca2e83 NC |
405 | |
406 | =for hackers | |
407 | Found in file hv.c | |
408 | ||
409 | ||
410 | =back | |
411 | ||
a4f1a029 NIS |
412 | =head1 IO Functions |
413 | ||
414 | =over 8 | |
645c22ef | 415 | |
a8586c98 | 416 | =item start_glob |
d8c40edc | 417 | X<start_glob> |
a8586c98 JH |
418 | |
419 | Function called by C<do_readline> to spawn a glob (or do the glob inside | |
420 | perl on VMS). This code used to be inline, but now perl uses C<File::Glob> | |
bd16a5f0 | 421 | this glob starter is only used by miniperl during the build process. |
a8586c98 JH |
422 | Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up. |
423 | ||
4048f010 | 424 | PerlIO* start_glob(SV *tmpglob, IO *io) |
a8586c98 JH |
425 | |
426 | =for hackers | |
427 | Found in file doio.c | |
428 | ||
a4f1a029 NIS |
429 | |
430 | =back | |
431 | ||
0cbee0a4 DM |
432 | =head1 Magical Functions |
433 | ||
434 | =over 8 | |
435 | ||
f175cff5 VP |
436 | =item magic_clearhint |
437 | X<magic_clearhint> | |
b3ca2e83 | 438 | |
c28fe1ec NC |
439 | Triggered by a delete from %^H, records the key to |
440 | C<PL_compiling.cop_hints_hash>. | |
b3ca2e83 | 441 | |
f175cff5 VP |
442 | int magic_clearhint(SV* sv, MAGIC* mg) |
443 | ||
444 | =for hackers | |
445 | Found in file mg.c | |
446 | ||
447 | =item magic_sethint | |
448 | X<magic_sethint> | |
449 | ||
450 | Triggered by a store to %^H, records the key/value pair to | |
451 | C<PL_compiling.cop_hints_hash>. It is assumed that hints aren't storing | |
452 | anything that would need a deep copy. Maybe we should warn if we find a | |
453 | reference. | |
454 | ||
b3ca2e83 NC |
455 | int magic_sethint(SV* sv, MAGIC* mg) |
456 | ||
457 | =for hackers | |
458 | Found in file mg.c | |
459 | ||
0cbee0a4 | 460 | =item mg_localize |
d8c40edc | 461 | X<mg_localize> |
0cbee0a4 DM |
462 | |
463 | Copy some of the magic from an existing SV to new localized version of | |
464 | that SV. Container magic (eg %ENV, $1, tie) gets copied, value magic | |
465 | doesn't (eg taint, pos). | |
466 | ||
467 | void mg_localize(SV* sv, SV* nsv) | |
468 | ||
469 | =for hackers | |
470 | Found in file mg.c | |
471 | ||
472 | ||
473 | =back | |
474 | ||
47c9dd14 BB |
475 | =head1 MRO Functions |
476 | ||
477 | =over 8 | |
478 | ||
c74c7a1e NC |
479 | =item mro_get_linear_isa_c3 |
480 | X<mro_get_linear_isa_c3> | |
481 | ||
482 | Returns the C3 linearization of @ISA | |
483 | the given stash. The return value is a read-only AV*. | |
484 | C<level> should be 0 (it is used internally in this | |
485 | function's recursion). | |
486 | ||
487 | You are responsible for C<SvREFCNT_inc()> on the | |
488 | return value if you plan to store it anywhere | |
489 | semi-permanently (otherwise it might be deleted | |
490 | out from under you the next time the cache is | |
491 | invalidated). | |
492 | ||
493 | AV* mro_get_linear_isa_c3(HV* stash, I32 level) | |
494 | ||
495 | =for hackers | |
496 | Found in file mro.c | |
497 | ||
498 | =item mro_get_linear_isa_dfs | |
499 | X<mro_get_linear_isa_dfs> | |
500 | ||
501 | Returns the Depth-First Search linearization of @ISA | |
502 | the given stash. The return value is a read-only AV*. | |
503 | C<level> should be 0 (it is used internally in this | |
504 | function's recursion). | |
505 | ||
506 | You are responsible for C<SvREFCNT_inc()> on the | |
507 | return value if you plan to store it anywhere | |
508 | semi-permanently (otherwise it might be deleted | |
509 | out from under you the next time the cache is | |
510 | invalidated). | |
511 | ||
512 | AV* mro_get_linear_isa_dfs(HV* stash, I32 level) | |
513 | ||
514 | =for hackers | |
515 | Found in file mro.c | |
516 | ||
47c9dd14 BB |
517 | =item mro_isa_changed_in |
518 | X<mro_isa_changed_in> | |
519 | ||
520 | Takes the necessary steps (cache invalidations, mostly) | |
521 | when the @ISA of the given package has changed. Invoked | |
522 | by the C<setisa> magic, should not need to invoke directly. | |
523 | ||
524 | void mro_isa_changed_in(HV* stash) | |
525 | ||
526 | =for hackers | |
527 | Found in file mro.c | |
528 | ||
529 | ||
530 | =back | |
531 | ||
a4f1a029 NIS |
532 | =head1 Pad Data Structures |
533 | ||
534 | =over 8 | |
535 | ||
536 | =item CvPADLIST | |
d8c40edc | 537 | X<CvPADLIST> |
a4f1a029 NIS |
538 | |
539 | CV's can have CvPADLIST(cv) set to point to an AV. | |
540 | ||
541 | For these purposes "forms" are a kind-of CV, eval""s are too (except they're | |
542 | not callable at will and are always thrown away after the eval"" is done | |
b5c19bd7 DM |
543 | executing). Require'd files are simply evals without any outer lexical |
544 | scope. | |
a4f1a029 NIS |
545 | |
546 | XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad, | |
547 | but that is really the callers pad (a slot of which is allocated by | |
548 | every entersub). | |
549 | ||
550 | The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items | |
f3548bdc | 551 | is managed "manual" (mostly in pad.c) rather than normal av.c rules. |
a4f1a029 NIS |
552 | The items in the AV are not SVs as for a normal AV, but other AVs: |
553 | ||
554 | 0'th Entry of the CvPADLIST is an AV which represents the "names" or rather | |
555 | the "static type information" for lexicals. | |
556 | ||
557 | The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that | |
558 | depth of recursion into the CV. | |
559 | The 0'th slot of a frame AV is an AV which is @_. | |
560 | other entries are storage for variables and op targets. | |
561 | ||
562 | During compilation: | |
a6d05634 TM |
563 | C<PL_comppad_name> is set to the names AV. |
564 | C<PL_comppad> is set to the frame AV for the frame CvDEPTH == 1. | |
565 | C<PL_curpad> is set to the body of the frame AV (i.e. AvARRAY(PL_comppad)). | |
a4f1a029 | 566 | |
f3548bdc DM |
567 | During execution, C<PL_comppad> and C<PL_curpad> refer to the live |
568 | frame of the currently executing sub. | |
569 | ||
570 | Iterating over the names AV iterates over all possible pad | |
a4f1a029 NIS |
571 | items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having |
572 | &PL_sv_undef "names" (see pad_alloc()). | |
573 | ||
574 | Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names. | |
575 | The rest are op targets/GVs/constants which are statically allocated | |
576 | or resolved at compile time. These don't have names by which they | |
577 | can be looked up from Perl code at run time through eval"" like | |
578 | my/our variables can be. Since they can't be looked up by "name" | |
579 | but only by their index allocated at compile time (which is usually | |
580 | in PL_op->op_targ), wasting a name SV for them doesn't make sense. | |
581 | ||
582 | The SVs in the names AV have their PV being the name of the variable. | |
00a0d662 NC |
583 | xlow+1..xhigh inclusive in the NV union is a range of cop_seq numbers for |
584 | which the name is valid. For typed lexicals name SV is SVt_PVMG and SvSTASH | |
585 | points at the type. For C<our> lexicals, the type is also SVt_PVMG, with the | |
44a2ac75 | 586 | SvOURSTASH slot pointing at the stash of the associated global (so that |
00a0d662 NC |
587 | duplicate C<our> declarations in the same package can be detected). SvUVX is |
588 | sometimes hijacked to store the generation number during compilation. | |
a4f1a029 | 589 | |
b5c19bd7 DM |
590 | If SvFAKE is set on the name SV, then that slot in the frame AV is |
591 | a REFCNT'ed reference to a lexical from "outside". In this case, | |
00a0d662 NC |
592 | the name SV does not use xlow and xhigh to store a cop_seq range, since it is |
593 | in scope throughout. Instead xhigh stores some flags containing info about | |
b5c19bd7 | 594 | the real lexical (is it declared in an anon, and is it capable of being |
00a0d662 | 595 | instantiated multiple times?), and for fake ANONs, xlow contains the index |
b5c19bd7 DM |
596 | within the parent's pad where the lexical's value is stored, to make |
597 | cloning quicker. | |
a4f1a029 | 598 | |
a6d05634 | 599 | If the 'name' is '&' the corresponding entry in frame AV |
a4f1a029 NIS |
600 | is a CV representing a possible closure. |
601 | (SvFAKE and name of '&' is not a meaningful combination currently but could | |
602 | become so if C<my sub foo {}> is implemented.) | |
603 | ||
5c3943b6 RGS |
604 | Note that formats are treated as anon subs, and are cloned each time |
605 | write is called (if necessary). | |
606 | ||
2814eb74 PJ |
607 | The flag SVf_PADSTALE is cleared on lexicals each time the my() is executed, |
608 | and set on scope exit. This allows the 'Variable $x is not available' warning | |
609 | to be generated in evals, such as | |
610 | ||
611 | { my $x = 1; sub f { eval '$x'} } f(); | |
612 | ||
3134ad69 NC |
613 | For state vars, SVf_PADSTALE is overloaded to mean 'not yet initialised' |
614 | ||
a4f1a029 NIS |
615 | AV * CvPADLIST(CV *cv) |
616 | ||
617 | =for hackers | |
dd2155a4 DM |
618 | Found in file pad.c |
619 | ||
620 | =item cv_clone | |
d8c40edc | 621 | X<cv_clone> |
dd2155a4 DM |
622 | |
623 | Clone a CV: make a new CV which points to the same code etc, but which | |
ad63d80f | 624 | has a newly-created pad built by copying the prototype pad and capturing |
dd2155a4 DM |
625 | any outer lexicals. |
626 | ||
627 | CV* cv_clone(CV* proto) | |
628 | ||
629 | =for hackers | |
630 | Found in file pad.c | |
631 | ||
632 | =item cv_dump | |
d8c40edc | 633 | X<cv_dump> |
dd2155a4 DM |
634 | |
635 | dump the contents of a CV | |
636 | ||
e1ec3a88 | 637 | void cv_dump(const CV *cv, const char *title) |
dd2155a4 DM |
638 | |
639 | =for hackers | |
640 | Found in file pad.c | |
641 | ||
642 | =item do_dump_pad | |
d8c40edc | 643 | X<do_dump_pad> |
dd2155a4 DM |
644 | |
645 | Dump the contents of a padlist | |
646 | ||
647 | void do_dump_pad(I32 level, PerlIO *file, PADLIST *padlist, int full) | |
648 | ||
649 | =for hackers | |
650 | Found in file pad.c | |
651 | ||
652 | =item intro_my | |
d8c40edc | 653 | X<intro_my> |
dd2155a4 DM |
654 | |
655 | "Introduce" my variables to visible status. | |
656 | ||
657 | U32 intro_my() | |
658 | ||
659 | =for hackers | |
660 | Found in file pad.c | |
661 | ||
662 | =item pad_add_anon | |
d8c40edc | 663 | X<pad_add_anon> |
dd2155a4 DM |
664 | |
665 | Add an anon code entry to the current compiling pad | |
666 | ||
667 | PADOFFSET pad_add_anon(SV* sv, OPCODE op_type) | |
668 | ||
669 | =for hackers | |
670 | Found in file pad.c | |
671 | ||
672 | =item pad_add_name | |
d8c40edc | 673 | X<pad_add_name> |
dd2155a4 | 674 | |
b5c19bd7 DM |
675 | Create a new name and associated PADMY SV in the current pad; return the |
676 | offset. | |
dd2155a4 DM |
677 | If C<typestash> is valid, the name is for a typed lexical; set the |
678 | name's stash to that value. | |
679 | If C<ourstash> is valid, it's an our lexical, set the name's | |
44a2ac75 | 680 | SvOURSTASH to that value |
dd2155a4 | 681 | |
dd2155a4 DM |
682 | If fake, it means we're cloning an existing entry |
683 | ||
952306ac | 684 | PADOFFSET pad_add_name(const char *name, HV* typestash, HV* ourstash, bool clone, bool state) |
dd2155a4 DM |
685 | |
686 | =for hackers | |
687 | Found in file pad.c | |
688 | ||
689 | =item pad_alloc | |
d8c40edc | 690 | X<pad_alloc> |
dd2155a4 DM |
691 | |
692 | Allocate a new my or tmp pad entry. For a my, simply push a null SV onto | |
693 | the end of PL_comppad, but for a tmp, scan the pad from PL_padix upwards | |
324092c6 | 694 | for a slot which has no name and no active value. |
dd2155a4 DM |
695 | |
696 | PADOFFSET pad_alloc(I32 optype, U32 tmptype) | |
697 | ||
698 | =for hackers | |
699 | Found in file pad.c | |
700 | ||
701 | =item pad_block_start | |
d8c40edc | 702 | X<pad_block_start> |
dd2155a4 DM |
703 | |
704 | Update the pad compilation state variables on entry to a new block | |
705 | ||
706 | void pad_block_start(int full) | |
707 | ||
708 | =for hackers | |
709 | Found in file pad.c | |
710 | ||
711 | =item pad_check_dup | |
d8c40edc | 712 | X<pad_check_dup> |
dd2155a4 DM |
713 | |
714 | Check for duplicate declarations: report any of: | |
715 | * a my in the current scope with the same name; | |
716 | * an our (anywhere in the pad) with the same name and the same stash | |
717 | as C<ourstash> | |
718 | C<is_our> indicates that the name to check is an 'our' declaration | |
719 | ||
e1ec3a88 | 720 | void pad_check_dup(const char* name, bool is_our, const HV* ourstash) |
dd2155a4 DM |
721 | |
722 | =for hackers | |
723 | Found in file pad.c | |
724 | ||
725 | =item pad_findlex | |
d8c40edc | 726 | X<pad_findlex> |
dd2155a4 DM |
727 | |
728 | Find a named lexical anywhere in a chain of nested pads. Add fake entries | |
b5c19bd7 DM |
729 | in the inner pads if it's found in an outer one. |
730 | ||
731 | Returns the offset in the bottom pad of the lex or the fake lex. | |
732 | cv is the CV in which to start the search, and seq is the current cop_seq | |
733 | to match against. If warn is true, print appropriate warnings. The out_* | |
734 | vars return values, and so are pointers to where the returned values | |
735 | should be stored. out_capture, if non-null, requests that the innermost | |
736 | instance of the lexical is captured; out_name_sv is set to the innermost | |
737 | matched namesv or fake namesv; out_flags returns the flags normally | |
738 | associated with the IVX field of a fake namesv. | |
739 | ||
740 | Note that pad_findlex() is recursive; it recurses up the chain of CVs, | |
741 | then comes back down, adding fake entries as it goes. It has to be this way | |
00a0d662 | 742 | because fake namesvs in anon protoypes have to store in xlow the index into |
b5c19bd7 DM |
743 | the parent pad. |
744 | ||
e1ec3a88 | 745 | PADOFFSET pad_findlex(const char *name, const CV* cv, U32 seq, int warn, SV** out_capture, SV** out_name_sv, int *out_flags) |
dd2155a4 DM |
746 | |
747 | =for hackers | |
748 | Found in file pad.c | |
749 | ||
750 | =item pad_findmy | |
d8c40edc | 751 | X<pad_findmy> |
dd2155a4 | 752 | |
ad63d80f | 753 | Given a lexical name, try to find its offset, first in the current pad, |
dd2155a4 | 754 | or failing that, in the pads of any lexically enclosing subs (including |
ad63d80f JP |
755 | the complications introduced by eval). If the name is found in an outer pad, |
756 | then a fake entry is added to the current pad. | |
dd2155a4 DM |
757 | Returns the offset in the current pad, or NOT_IN_PAD on failure. |
758 | ||
e1ec3a88 | 759 | PADOFFSET pad_findmy(const char* name) |
dd2155a4 DM |
760 | |
761 | =for hackers | |
762 | Found in file pad.c | |
763 | ||
764 | =item pad_fixup_inner_anons | |
d8c40edc | 765 | X<pad_fixup_inner_anons> |
dd2155a4 DM |
766 | |
767 | For any anon CVs in the pad, change CvOUTSIDE of that CV from | |
7dafbf52 DM |
768 | old_cv to new_cv if necessary. Needed when a newly-compiled CV has to be |
769 | moved to a pre-existing CV struct. | |
dd2155a4 DM |
770 | |
771 | void pad_fixup_inner_anons(PADLIST *padlist, CV *old_cv, CV *new_cv) | |
772 | ||
773 | =for hackers | |
774 | Found in file pad.c | |
775 | ||
776 | =item pad_free | |
d8c40edc | 777 | X<pad_free> |
dd2155a4 | 778 | |
d7f8936a | 779 | Free the SV at offset po in the current pad. |
dd2155a4 DM |
780 | |
781 | void pad_free(PADOFFSET po) | |
782 | ||
783 | =for hackers | |
784 | Found in file pad.c | |
785 | ||
786 | =item pad_leavemy | |
d8c40edc | 787 | X<pad_leavemy> |
dd2155a4 DM |
788 | |
789 | Cleanup at end of scope during compilation: set the max seq number for | |
790 | lexicals in this scope and warn of any lexicals that never got introduced. | |
791 | ||
792 | void pad_leavemy() | |
793 | ||
794 | =for hackers | |
795 | Found in file pad.c | |
796 | ||
797 | =item pad_new | |
d8c40edc | 798 | X<pad_new> |
dd2155a4 | 799 | |
ad63d80f | 800 | Create a new compiling padlist, saving and updating the various global |
dd2155a4 DM |
801 | vars at the same time as creating the pad itself. The following flags |
802 | can be OR'ed together: | |
803 | ||
804 | padnew_CLONE this pad is for a cloned CV | |
805 | padnew_SAVE save old globals | |
806 | padnew_SAVESUB also save extra stuff for start of sub | |
807 | ||
c7c737cb | 808 | PADLIST* pad_new(int flags) |
dd2155a4 DM |
809 | |
810 | =for hackers | |
811 | Found in file pad.c | |
812 | ||
813 | =item pad_push | |
d8c40edc | 814 | X<pad_push> |
dd2155a4 DM |
815 | |
816 | Push a new pad frame onto the padlist, unless there's already a pad at | |
26019298 AL |
817 | this depth, in which case don't bother creating a new one. Then give |
818 | the new pad an @_ in slot zero. | |
dd2155a4 | 819 | |
26019298 | 820 | void pad_push(PADLIST *padlist, int depth) |
dd2155a4 DM |
821 | |
822 | =for hackers | |
823 | Found in file pad.c | |
824 | ||
825 | =item pad_reset | |
d8c40edc | 826 | X<pad_reset> |
dd2155a4 DM |
827 | |
828 | Mark all the current temporaries for reuse | |
829 | ||
830 | void pad_reset() | |
831 | ||
832 | =for hackers | |
833 | Found in file pad.c | |
834 | ||
835 | =item pad_setsv | |
d8c40edc | 836 | X<pad_setsv> |
dd2155a4 DM |
837 | |
838 | Set the entry at offset po in the current pad to sv. | |
839 | Use the macro PAD_SETSV() rather than calling this function directly. | |
840 | ||
841 | void pad_setsv(PADOFFSET po, SV* sv) | |
842 | ||
843 | =for hackers | |
844 | Found in file pad.c | |
845 | ||
846 | =item pad_swipe | |
d8c40edc | 847 | X<pad_swipe> |
dd2155a4 DM |
848 | |
849 | Abandon the tmp in the current pad at offset po and replace with a | |
850 | new one. | |
851 | ||
852 | void pad_swipe(PADOFFSET po, bool refadjust) | |
853 | ||
854 | =for hackers | |
855 | Found in file pad.c | |
856 | ||
857 | =item pad_tidy | |
d8c40edc | 858 | X<pad_tidy> |
dd2155a4 DM |
859 | |
860 | Tidy up a pad after we've finished compiling it: | |
861 | * remove most stuff from the pads of anonsub prototypes; | |
862 | * give it a @_; | |
863 | * mark tmps as such. | |
864 | ||
865 | void pad_tidy(padtidy_type type) | |
866 | ||
867 | =for hackers | |
868 | Found in file pad.c | |
869 | ||
870 | =item pad_undef | |
d8c40edc | 871 | X<pad_undef> |
dd2155a4 DM |
872 | |
873 | Free the padlist associated with a CV. | |
874 | If parts of it happen to be current, we null the relevant | |
875 | PL_*pad* global vars so that we don't have any dangling references left. | |
876 | We also repoint the CvOUTSIDE of any about-to-be-orphaned | |
a3985cdc | 877 | inner subs to the outer of this cv. |
dd2155a4 | 878 | |
7dafbf52 DM |
879 | (This function should really be called pad_free, but the name was already |
880 | taken) | |
881 | ||
a3985cdc | 882 | void pad_undef(CV* cv) |
dd2155a4 DM |
883 | |
884 | =for hackers | |
885 | Found in file pad.c | |
a4f1a029 NIS |
886 | |
887 | ||
888 | =back | |
889 | ||
907b3e23 DM |
890 | =head1 Per-Interpreter Variables |
891 | ||
892 | =over 8 | |
893 | ||
894 | =item PL_DBsingle | |
895 | X<PL_DBsingle> | |
896 | ||
897 | When Perl is run in debugging mode, with the B<-d> switch, this SV is a | |
898 | boolean which indicates whether subs are being single-stepped. | |
899 | Single-stepping is automatically turned on after every step. This is the C | |
900 | variable which corresponds to Perl's $DB::single variable. See | |
901 | C<PL_DBsub>. | |
902 | ||
903 | SV * PL_DBsingle | |
904 | ||
905 | =for hackers | |
906 | Found in file intrpvar.h | |
907 | ||
908 | =item PL_DBsub | |
909 | X<PL_DBsub> | |
910 | ||
911 | When Perl is run in debugging mode, with the B<-d> switch, this GV contains | |
912 | the SV which holds the name of the sub being debugged. This is the C | |
913 | variable which corresponds to Perl's $DB::sub variable. See | |
914 | C<PL_DBsingle>. | |
915 | ||
916 | GV * PL_DBsub | |
917 | ||
918 | =for hackers | |
919 | Found in file intrpvar.h | |
920 | ||
921 | =item PL_DBtrace | |
922 | X<PL_DBtrace> | |
923 | ||
924 | Trace variable used when Perl is run in debugging mode, with the B<-d> | |
925 | switch. This is the C variable which corresponds to Perl's $DB::trace | |
926 | variable. See C<PL_DBsingle>. | |
927 | ||
928 | SV * PL_DBtrace | |
929 | ||
930 | =for hackers | |
931 | Found in file intrpvar.h | |
932 | ||
933 | =item PL_dowarn | |
934 | X<PL_dowarn> | |
935 | ||
936 | The C variable which corresponds to Perl's $^W warning variable. | |
937 | ||
938 | bool PL_dowarn | |
939 | ||
940 | =for hackers | |
941 | Found in file intrpvar.h | |
942 | ||
943 | =item PL_last_in_gv | |
944 | X<PL_last_in_gv> | |
945 | ||
946 | The GV which was last used for a filehandle input operation. (C<< <FH> >>) | |
947 | ||
948 | GV* PL_last_in_gv | |
949 | ||
950 | =for hackers | |
951 | Found in file intrpvar.h | |
952 | ||
953 | =item PL_ofs_sv | |
954 | X<PL_ofs_sv> | |
955 | ||
956 | The output field separator - C<$,> in Perl space. | |
957 | ||
958 | SV* PL_ofs_sv | |
959 | ||
960 | =for hackers | |
961 | Found in file intrpvar.h | |
962 | ||
963 | =item PL_rs | |
964 | X<PL_rs> | |
965 | ||
966 | The input record separator - C<$/> in Perl space. | |
967 | ||
968 | SV* PL_rs | |
969 | ||
970 | =for hackers | |
971 | Found in file intrpvar.h | |
972 | ||
973 | ||
974 | =back | |
975 | ||
a4f1a029 NIS |
976 | =head1 Stack Manipulation Macros |
977 | ||
978 | =over 8 | |
979 | ||
980 | =item djSP | |
d8c40edc | 981 | X<djSP> |
a4f1a029 NIS |
982 | |
983 | Declare Just C<SP>. This is actually identical to C<dSP>, and declares | |
984 | a local copy of perl's stack pointer, available via the C<SP> macro. | |
985 | See C<SP>. (Available for backward source code compatibility with the | |
986 | old (Perl 5.005) thread model.) | |
987 | ||
988 | djSP; | |
989 | ||
990 | =for hackers | |
991 | Found in file pp.h | |
992 | ||
993 | =item LVRET | |
d8c40edc | 994 | X<LVRET> |
a4f1a029 NIS |
995 | |
996 | True if this op will be the return value of an lvalue subroutine | |
997 | ||
998 | =for hackers | |
999 | Found in file pp.h | |
1000 | ||
1001 | ||
1002 | =back | |
1003 | ||
1004 | =head1 SV Manipulation Functions | |
1005 | ||
1006 | =over 8 | |
1007 | ||
645c22ef | 1008 | =item sv_add_arena |
d8c40edc | 1009 | X<sv_add_arena> |
645c22ef DM |
1010 | |
1011 | Given a chunk of memory, link it to the head of the list of arenas, | |
1012 | and split it into a list of free SVs. | |
1013 | ||
de37a194 | 1014 | void sv_add_arena(char *const ptr, const U32 size, const U32 flags) |
645c22ef DM |
1015 | |
1016 | =for hackers | |
1017 | Found in file sv.c | |
1018 | ||
1019 | =item sv_clean_all | |
d8c40edc | 1020 | X<sv_clean_all> |
645c22ef DM |
1021 | |
1022 | Decrement the refcnt of each remaining SV, possibly triggering a | |
1023 | cleanup. This function may have to be called multiple times to free | |
8fb26106 | 1024 | SVs which are in complex self-referential hierarchies. |
645c22ef DM |
1025 | |
1026 | I32 sv_clean_all() | |
1027 | ||
1028 | =for hackers | |
1029 | Found in file sv.c | |
1030 | ||
1031 | =item sv_clean_objs | |
d8c40edc | 1032 | X<sv_clean_objs> |
645c22ef DM |
1033 | |
1034 | Attempt to destroy all objects not yet freed | |
1035 | ||
1036 | void sv_clean_objs() | |
1037 | ||
1038 | =for hackers | |
1039 | Found in file sv.c | |
1040 | ||
1041 | =item sv_free_arenas | |
d8c40edc | 1042 | X<sv_free_arenas> |
645c22ef DM |
1043 | |
1044 | Deallocate the memory used by all arenas. Note that all the individual SV | |
1045 | heads and bodies within the arenas must already have been freed. | |
1046 | ||
1047 | void sv_free_arenas() | |
1048 | ||
1049 | =for hackers | |
1050 | Found in file sv.c | |
1051 | ||
a4f1a029 | 1052 | |
954c1994 GS |
1053 | =back |
1054 | ||
800401ee JH |
1055 | =head1 SV-Body Allocation |
1056 | ||
1057 | =over 8 | |
1058 | ||
1059 | =item sv_2num | |
1060 | X<sv_2num> | |
1061 | ||
1062 | Return an SV with the numeric value of the source SV, doing any necessary | |
a196a5fa JH |
1063 | reference or overload conversion. You must use the C<SvNUM(sv)> macro to |
1064 | access this function. | |
800401ee | 1065 | |
5de3775c | 1066 | SV* sv_2num(SV *const sv) |
800401ee JH |
1067 | |
1068 | =for hackers | |
1069 | Found in file sv.c | |
1070 | ||
1071 | ||
1072 | =back | |
1073 | ||
979f2922 TS |
1074 | =head1 Unicode Support |
1075 | ||
1076 | =over 8 | |
1077 | ||
1078 | =item find_uninit_var | |
1079 | X<find_uninit_var> | |
1080 | ||
1081 | Find the name of the undefined variable (if any) that caused the operator o | |
1082 | to issue a "Use of uninitialized value" warning. | |
1083 | If match is true, only return a name if it's value matches uninit_sv. | |
1084 | So roughly speaking, if a unary operator (such as OP_COS) generates a | |
1085 | warning, then following the direct child of the op may yield an | |
1086 | OP_PADSV or OP_GV that gives the name of the undefined variable. On the | |
1087 | other hand, with OP_ADD there are two branches to follow, so we only print | |
1088 | the variable name if we get an exact match. | |
1089 | ||
1090 | The name is returned as a mortal SV. | |
1091 | ||
1092 | Assumes that PL_op is the op that originally triggered the error, and that | |
1093 | PL_comppad/PL_curpad points to the currently executing pad. | |
1094 | ||
1095 | SV* find_uninit_var(OP* obase, SV* uninit_sv, bool top) | |
1096 | ||
1097 | =for hackers | |
1098 | Found in file sv.c | |
1099 | ||
1100 | =item report_uninit | |
1101 | X<report_uninit> | |
1102 | ||
1103 | Print appropriate "Use of uninitialized variable" warning | |
1104 | ||
1105 | void report_uninit(SV* uninit_sv) | |
1106 | ||
1107 | =for hackers | |
1108 | Found in file sv.c | |
1109 | ||
1110 | ||
1111 | =back | |
1112 | ||
954c1994 GS |
1113 | =head1 AUTHORS |
1114 | ||
1c846c1f NIS |
1115 | The autodocumentation system was originally added to the Perl core by |
1116 | Benjamin Stuhl. Documentation is by whoever was kind enough to | |
954c1994 GS |
1117 | document their functions. |
1118 | ||
1119 | =head1 SEE ALSO | |
1120 | ||
1121 | perlguts(1), perlapi(1) | |
1122 | ||
3f98fbb3 RGS |
1123 | =cut |
1124 | ||
1125 | ex: set ro: |