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954c1994 GS |
1 | =head1 NAME |
2 | ||
1c846c1f | 3 | perlintern - autogenerated documentation of purely B<internal> |
954c1994 GS |
4 | Perl functions |
5 | ||
6 | =head1 DESCRIPTION | |
7 | ||
1c846c1f | 8 | This file is the autogenerated documentation of functions in the |
4375e838 | 9 | Perl interpreter that are documented using Perl's internal documentation |
1c846c1f | 10 | format but are not marked as part of the Perl API. In other words, |
954c1994 GS |
11 | B<they are not for use in extensions>! |
12 | ||
a8586c98 | 13 | |
7dafbf52 DM |
14 | =head1 CV reference counts and CvOUTSIDE |
15 | ||
16 | =over 8 | |
17 | ||
18 | =item CvWEAKOUTSIDE | |
19 | ||
20 | Each CV has a pointer, C<CvOUTSIDE()>, to its lexically enclosing | |
21 | CV (if any). Because pointers to anonymous sub prototypes are | |
22 | stored in C<&> pad slots, it is a possible to get a circular reference, | |
23 | with the parent pointing to the child and vice-versa. To avoid the | |
24 | ensuing memory leak, we do not increment the reference count of the CV | |
25 | pointed to by C<CvOUTSIDE> in the I<one specific instance> that the parent | |
26 | has a C<&> pad slot pointing back to us. In this case, we set the | |
27 | C<CvWEAKOUTSIDE> flag in the child. This allows us to determine under what | |
28 | circumstances we should decrement the refcount of the parent when freeing | |
29 | the child. | |
30 | ||
31 | There is a further complication with non-closure anonymous subs (ie those | |
32 | that do not refer to any lexicals outside that sub). In this case, the | |
33 | anonymous prototype is shared rather than being cloned. This has the | |
34 | consequence that the parent may be freed while there are still active | |
35 | children, eg | |
36 | ||
37 | BEGIN { $a = sub { eval '$x' } } | |
38 | ||
39 | In this case, the BEGIN is freed immediately after execution since there | |
40 | are no active references to it: the anon sub prototype has | |
41 | C<CvWEAKOUTSIDE> set since it's not a closure, and $a points to the same | |
42 | CV, so it doesn't contribute to BEGIN's refcount either. When $a is | |
43 | executed, the C<eval '$x'> causes the chain of C<CvOUTSIDE>s to be followed, | |
44 | and the freed BEGIN is accessed. | |
45 | ||
46 | To avoid this, whenever a CV and its associated pad is freed, any | |
47 | C<&> entries in the pad are explicitly removed from the pad, and if the | |
48 | refcount of the pointed-to anon sub is still positive, then that | |
49 | child's C<CvOUTSIDE> is set to point to its grandparent. This will only | |
50 | occur in the single specific case of a non-closure anon prototype | |
51 | having one or more active references (such as C<$a> above). | |
52 | ||
53 | One other thing to consider is that a CV may be merely undefined | |
54 | rather than freed, eg C<undef &foo>. In this case, its refcount may | |
55 | not have reached zero, but we still delete its pad and its C<CvROOT> etc. | |
56 | Since various children may still have their C<CvOUTSIDE> pointing at this | |
57 | undefined CV, we keep its own C<CvOUTSIDE> for the time being, so that | |
58 | the chain of lexical scopes is unbroken. For example, the following | |
59 | should print 123: | |
60 | ||
61 | my $x = 123; | |
62 | sub tmp { sub { eval '$x' } } | |
63 | my $a = tmp(); | |
64 | undef &tmp; | |
65 | print $a->(); | |
66 | ||
67 | bool CvWEAKOUTSIDE(CV *cv) | |
68 | ||
69 | =for hackers | |
70 | Found in file cv.h | |
71 | ||
72 | ||
73 | =back | |
74 | ||
dd2155a4 DM |
75 | =head1 Functions in file pad.h |
76 | ||
77 | ||
78 | =over 8 | |
79 | ||
80 | =item CX_CURPAD_SAVE | |
81 | ||
82 | Save the current pad in the given context block structure. | |
83 | ||
84 | void CX_CURPAD_SAVE(struct context) | |
85 | ||
86 | =for hackers | |
87 | Found in file pad.h | |
88 | ||
89 | =item CX_CURPAD_SV | |
90 | ||
91 | Access the SV at offset po in the saved current pad in the given | |
92 | context block structure (can be used as an lvalue). | |
93 | ||
f3548bdc | 94 | SV * CX_CURPAD_SV(struct context, PADOFFSET po) |
dd2155a4 DM |
95 | |
96 | =for hackers | |
97 | Found in file pad.h | |
98 | ||
99 | =item PAD_BASE_SV | |
100 | ||
101 | Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist | |
102 | ||
103 | SV * PAD_BASE_SV (PADLIST padlist, PADOFFSET po) | |
104 | ||
105 | =for hackers | |
106 | Found in file pad.h | |
107 | ||
108 | =item PAD_CLONE_VARS | |
109 | ||
110 | |CLONE_PARAMS* param | |
111 | Clone the state variables associated with running and compiling pads. | |
112 | ||
113 | void PAD_CLONE_VARS(PerlInterpreter *proto_perl \) | |
114 | ||
115 | =for hackers | |
116 | Found in file pad.h | |
117 | ||
118 | =item PAD_COMPNAME_FLAGS | |
119 | ||
120 | Return the flags for the current compiling pad name | |
121 | at offset C<po>. Assumes a valid slot entry. | |
122 | ||
123 | U32 PAD_COMPNAME_FLAGS(PADOFFSET po) | |
124 | ||
125 | =for hackers | |
126 | Found in file pad.h | |
127 | ||
128 | =item PAD_COMPNAME_GEN | |
129 | ||
130 | The generation number of the name at offset C<po> in the current | |
131 | compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose. | |
132 | ||
133 | STRLEN PAD_COMPNAME_GEN(PADOFFSET po) | |
134 | ||
135 | =for hackers | |
136 | Found in file pad.h | |
137 | ||
27da23d5 JH |
138 | =item PAD_COMPNAME_GEN_set |
139 | ||
140 | Sets the generation number of the name at offset C<po> in the current | |
141 | ling pad (lvalue) to C<gen>. Note that C<SvCUR_set> is hijacked for this purpose. | |
142 | ||
143 | STRLEN PAD_COMPNAME_GEN_set(PADOFFSET po, int gen) | |
144 | ||
145 | =for hackers | |
146 | Found in file pad.h | |
147 | ||
dd2155a4 DM |
148 | =item PAD_COMPNAME_OURSTASH |
149 | ||
150 | Return the stash associated with an C<our> variable. | |
151 | Assumes the slot entry is a valid C<our> lexical. | |
152 | ||
153 | HV * PAD_COMPNAME_OURSTASH(PADOFFSET po) | |
154 | ||
155 | =for hackers | |
156 | Found in file pad.h | |
157 | ||
158 | =item PAD_COMPNAME_PV | |
159 | ||
160 | Return the name of the current compiling pad name | |
161 | at offset C<po>. Assumes a valid slot entry. | |
162 | ||
163 | char * PAD_COMPNAME_PV(PADOFFSET po) | |
164 | ||
165 | =for hackers | |
166 | Found in file pad.h | |
167 | ||
168 | =item PAD_COMPNAME_TYPE | |
169 | ||
170 | Return the type (stash) of the current compiling pad name at offset | |
171 | C<po>. Must be a valid name. Returns null if not typed. | |
172 | ||
173 | HV * PAD_COMPNAME_TYPE(PADOFFSET po) | |
174 | ||
175 | =for hackers | |
176 | Found in file pad.h | |
177 | ||
178 | =item PAD_DUP | |
179 | ||
180 | Clone a padlist. | |
181 | ||
182 | void PAD_DUP(PADLIST dstpad, PADLIST srcpad, CLONE_PARAMS* param) | |
183 | ||
184 | =for hackers | |
185 | Found in file pad.h | |
186 | ||
f3548bdc DM |
187 | =item PAD_RESTORE_LOCAL |
188 | ||
189 | Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL() | |
190 | ||
191 | void PAD_RESTORE_LOCAL(PAD *opad) | |
192 | ||
193 | =for hackers | |
194 | Found in file pad.h | |
195 | ||
196 | =item PAD_SAVE_LOCAL | |
197 | ||
198 | Save the current pad to the local variable opad, then make the | |
199 | current pad equal to npad | |
200 | ||
201 | void PAD_SAVE_LOCAL(PAD *opad, PAD *npad) | |
202 | ||
203 | =for hackers | |
204 | Found in file pad.h | |
205 | ||
dd2155a4 DM |
206 | =item PAD_SAVE_SETNULLPAD |
207 | ||
208 | Save the current pad then set it to null. | |
209 | ||
210 | void PAD_SAVE_SETNULLPAD() | |
211 | ||
212 | =for hackers | |
213 | Found in file pad.h | |
214 | ||
215 | =item PAD_SETSV | |
216 | ||
217 | Set the slot at offset C<po> in the current pad to C<sv> | |
218 | ||
219 | SV * PAD_SETSV (PADOFFSET po, SV* sv) | |
220 | ||
221 | =for hackers | |
222 | Found in file pad.h | |
223 | ||
224 | =item PAD_SET_CUR | |
225 | ||
226 | Set the current pad to be pad C<n> in the padlist, saving | |
227 | the previous current pad. | |
228 | ||
229 | void PAD_SET_CUR (PADLIST padlist, I32 n) | |
230 | ||
231 | =for hackers | |
232 | Found in file pad.h | |
233 | ||
bf9cdc68 RG |
234 | =item PAD_SET_CUR_NOSAVE |
235 | ||
236 | like PAD_SET_CUR, but without the save | |
237 | ||
238 | void PAD_SET_CUR_NOSAVE (PADLIST padlist, I32 n) | |
239 | ||
240 | =for hackers | |
241 | Found in file pad.h | |
242 | ||
dd2155a4 DM |
243 | =item PAD_SV |
244 | ||
245 | Get the value at offset C<po> in the current pad | |
246 | ||
247 | void PAD_SV (PADOFFSET po) | |
248 | ||
249 | =for hackers | |
250 | Found in file pad.h | |
251 | ||
252 | =item PAD_SVl | |
253 | ||
254 | Lightweight and lvalue version of C<PAD_SV>. | |
255 | Get or set the value at offset C<po> in the current pad. | |
256 | Unlike C<PAD_SV>, does not print diagnostics with -DX. | |
257 | For internal use only. | |
258 | ||
259 | SV * PAD_SVl (PADOFFSET po) | |
260 | ||
261 | =for hackers | |
262 | Found in file pad.h | |
263 | ||
dd2155a4 DM |
264 | =item SAVECLEARSV |
265 | ||
266 | Clear the pointed to pad value on scope exit. (ie the runtime action of 'my') | |
267 | ||
268 | void SAVECLEARSV (SV **svp) | |
269 | ||
270 | =for hackers | |
271 | Found in file pad.h | |
272 | ||
273 | =item SAVECOMPPAD | |
274 | ||
275 | save PL_comppad and PL_curpad | |
276 | ||
dd2155a4 | 277 | |
dd2155a4 DM |
278 | |
279 | ||
280 | ||
f3548bdc | 281 | void SAVECOMPPAD() |
dd2155a4 DM |
282 | |
283 | =for hackers | |
284 | Found in file pad.h | |
285 | ||
286 | =item SAVEPADSV | |
287 | ||
288 | Save a pad slot (used to restore after an iteration) | |
289 | ||
f3548bdc | 290 | XXX DAPM it would make more sense to make the arg a PADOFFSET |
dd2155a4 DM |
291 | void SAVEPADSV (PADOFFSET po) |
292 | ||
293 | =for hackers | |
294 | Found in file pad.h | |
295 | ||
296 | ||
297 | =back | |
298 | ||
a3985cdc DM |
299 | =head1 Functions in file pp_ctl.c |
300 | ||
301 | ||
302 | =over 8 | |
303 | ||
304 | =item find_runcv | |
305 | ||
306 | Locate the CV corresponding to the currently executing sub or eval. | |
d819b83a DM |
307 | If db_seqp is non_null, skip CVs that are in the DB package and populate |
308 | *db_seqp with the cop sequence number at the point that the DB:: code was | |
309 | entered. (allows debuggers to eval in the scope of the breakpoint rather | |
8006bbc3 | 310 | than in in the scope of the debugger itself). |
a3985cdc | 311 | |
d819b83a | 312 | CV* find_runcv(U32 *db_seqp) |
a3985cdc DM |
313 | |
314 | =for hackers | |
315 | Found in file pp_ctl.c | |
316 | ||
317 | ||
318 | =back | |
319 | ||
a4f1a029 | 320 | =head1 Global Variables |
78f9721b | 321 | |
a4f1a029 | 322 | =over 8 |
78f9721b | 323 | |
2eb25c99 JH |
324 | =item PL_DBsingle |
325 | ||
326 | When Perl is run in debugging mode, with the B<-d> switch, this SV is a | |
327 | boolean which indicates whether subs are being single-stepped. | |
328 | Single-stepping is automatically turned on after every step. This is the C | |
329 | variable which corresponds to Perl's $DB::single variable. See | |
330 | C<PL_DBsub>. | |
331 | ||
332 | SV * PL_DBsingle | |
333 | ||
334 | =for hackers | |
335 | Found in file intrpvar.h | |
336 | ||
337 | =item PL_DBsub | |
338 | ||
339 | When Perl is run in debugging mode, with the B<-d> switch, this GV contains | |
340 | the SV which holds the name of the sub being debugged. This is the C | |
341 | variable which corresponds to Perl's $DB::sub variable. See | |
342 | C<PL_DBsingle>. | |
343 | ||
344 | GV * PL_DBsub | |
345 | ||
346 | =for hackers | |
347 | Found in file intrpvar.h | |
348 | ||
349 | =item PL_DBtrace | |
350 | ||
351 | Trace variable used when Perl is run in debugging mode, with the B<-d> | |
352 | switch. This is the C variable which corresponds to Perl's $DB::trace | |
353 | variable. See C<PL_DBsingle>. | |
354 | ||
355 | SV * PL_DBtrace | |
356 | ||
357 | =for hackers | |
358 | Found in file intrpvar.h | |
359 | ||
360 | =item PL_dowarn | |
361 | ||
362 | The C variable which corresponds to Perl's $^W warning variable. | |
363 | ||
364 | bool PL_dowarn | |
365 | ||
366 | =for hackers | |
367 | Found in file intrpvar.h | |
368 | ||
369 | =item PL_last_in_gv | |
370 | ||
371 | The GV which was last used for a filehandle input operation. (C<< <FH> >>) | |
372 | ||
373 | GV* PL_last_in_gv | |
374 | ||
375 | =for hackers | |
376 | Found in file thrdvar.h | |
377 | ||
378 | =item PL_ofs_sv | |
379 | ||
380 | The output field separator - C<$,> in Perl space. | |
381 | ||
382 | SV* PL_ofs_sv | |
383 | ||
384 | =for hackers | |
385 | Found in file thrdvar.h | |
386 | ||
387 | =item PL_rs | |
388 | ||
389 | The input record separator - C<$/> in Perl space. | |
390 | ||
391 | SV* PL_rs | |
392 | ||
393 | =for hackers | |
394 | Found in file thrdvar.h | |
395 | ||
645c22ef | 396 | |
a4f1a029 | 397 | =back |
645c22ef | 398 | |
a4f1a029 NIS |
399 | =head1 GV Functions |
400 | ||
401 | =over 8 | |
402 | ||
403 | =item is_gv_magical | |
404 | ||
405 | Returns C<TRUE> if given the name of a magical GV. | |
406 | ||
407 | Currently only useful internally when determining if a GV should be | |
408 | created even in rvalue contexts. | |
409 | ||
410 | C<flags> is not used at present but available for future extension to | |
411 | allow selecting particular classes of magical variable. | |
412 | ||
766f8916 MHM |
413 | Currently assumes that C<name> is NUL terminated (as well as len being valid). |
414 | This assumption is met by all callers within the perl core, which all pass | |
415 | pointers returned by SvPV. | |
416 | ||
7fc63493 AL |
417 | bool is_gv_magical(const char *name, STRLEN len, U32 flags) |
418 | ||
419 | =for hackers | |
420 | Found in file gv.c | |
421 | ||
422 | =item is_gv_magical_sv | |
423 | ||
424 | Returns C<TRUE> if given the name of a magical GV. Calls is_gv_magical. | |
425 | ||
426 | bool is_gv_magical_sv(SV *name, U32 flags) | |
645c22ef DM |
427 | |
428 | =for hackers | |
a4f1a029 NIS |
429 | Found in file gv.c |
430 | ||
431 | ||
432 | =back | |
433 | ||
434 | =head1 IO Functions | |
435 | ||
436 | =over 8 | |
645c22ef | 437 | |
a8586c98 JH |
438 | =item start_glob |
439 | ||
440 | Function called by C<do_readline> to spawn a glob (or do the glob inside | |
441 | perl on VMS). This code used to be inline, but now perl uses C<File::Glob> | |
bd16a5f0 | 442 | this glob starter is only used by miniperl during the build process. |
a8586c98 JH |
443 | Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up. |
444 | ||
445 | PerlIO* start_glob(SV* pattern, IO *io) | |
446 | ||
447 | =for hackers | |
448 | Found in file doio.c | |
449 | ||
a4f1a029 NIS |
450 | |
451 | =back | |
452 | ||
453 | =head1 Pad Data Structures | |
454 | ||
455 | =over 8 | |
456 | ||
457 | =item CvPADLIST | |
458 | ||
459 | CV's can have CvPADLIST(cv) set to point to an AV. | |
460 | ||
461 | For these purposes "forms" are a kind-of CV, eval""s are too (except they're | |
462 | not callable at will and are always thrown away after the eval"" is done | |
b5c19bd7 DM |
463 | executing). Require'd files are simply evals without any outer lexical |
464 | scope. | |
a4f1a029 NIS |
465 | |
466 | XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad, | |
467 | but that is really the callers pad (a slot of which is allocated by | |
468 | every entersub). | |
469 | ||
470 | The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items | |
f3548bdc | 471 | is managed "manual" (mostly in pad.c) rather than normal av.c rules. |
a4f1a029 NIS |
472 | The items in the AV are not SVs as for a normal AV, but other AVs: |
473 | ||
474 | 0'th Entry of the CvPADLIST is an AV which represents the "names" or rather | |
475 | the "static type information" for lexicals. | |
476 | ||
477 | The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that | |
478 | depth of recursion into the CV. | |
479 | The 0'th slot of a frame AV is an AV which is @_. | |
480 | other entries are storage for variables and op targets. | |
481 | ||
482 | During compilation: | |
a6d05634 TM |
483 | C<PL_comppad_name> is set to the names AV. |
484 | C<PL_comppad> is set to the frame AV for the frame CvDEPTH == 1. | |
485 | C<PL_curpad> is set to the body of the frame AV (i.e. AvARRAY(PL_comppad)). | |
a4f1a029 | 486 | |
f3548bdc DM |
487 | During execution, C<PL_comppad> and C<PL_curpad> refer to the live |
488 | frame of the currently executing sub. | |
489 | ||
490 | Iterating over the names AV iterates over all possible pad | |
a4f1a029 NIS |
491 | items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having |
492 | &PL_sv_undef "names" (see pad_alloc()). | |
493 | ||
494 | Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names. | |
495 | The rest are op targets/GVs/constants which are statically allocated | |
496 | or resolved at compile time. These don't have names by which they | |
497 | can be looked up from Perl code at run time through eval"" like | |
498 | my/our variables can be. Since they can't be looked up by "name" | |
499 | but only by their index allocated at compile time (which is usually | |
500 | in PL_op->op_targ), wasting a name SV for them doesn't make sense. | |
501 | ||
502 | The SVs in the names AV have their PV being the name of the variable. | |
dd2155a4 DM |
503 | NV+1..IV inclusive is a range of cop_seq numbers for which the name is |
504 | valid. For typed lexicals name SV is SVt_PVMG and SvSTASH points at the | |
505 | type. For C<our> lexicals, the type is SVt_PVGV, and GvSTASH points at the | |
506 | stash of the associated global (so that duplicate C<our> delarations in the | |
507 | same package can be detected). SvCUR is sometimes hijacked to | |
508 | store the generation number during compilation. | |
a4f1a029 | 509 | |
b5c19bd7 DM |
510 | If SvFAKE is set on the name SV, then that slot in the frame AV is |
511 | a REFCNT'ed reference to a lexical from "outside". In this case, | |
512 | the name SV does not use NVX and IVX to store a cop_seq range, since it is | |
513 | in scope throughout. Instead IVX stores some flags containing info about | |
514 | the real lexical (is it declared in an anon, and is it capable of being | |
515 | instantiated multiple times?), and for fake ANONs, NVX contains the index | |
516 | within the parent's pad where the lexical's value is stored, to make | |
517 | cloning quicker. | |
a4f1a029 | 518 | |
a6d05634 | 519 | If the 'name' is '&' the corresponding entry in frame AV |
a4f1a029 NIS |
520 | is a CV representing a possible closure. |
521 | (SvFAKE and name of '&' is not a meaningful combination currently but could | |
522 | become so if C<my sub foo {}> is implemented.) | |
523 | ||
5c3943b6 RGS |
524 | Note that formats are treated as anon subs, and are cloned each time |
525 | write is called (if necessary). | |
526 | ||
2814eb74 PJ |
527 | The flag SVf_PADSTALE is cleared on lexicals each time the my() is executed, |
528 | and set on scope exit. This allows the 'Variable $x is not available' warning | |
529 | to be generated in evals, such as | |
530 | ||
531 | { my $x = 1; sub f { eval '$x'} } f(); | |
532 | ||
a4f1a029 NIS |
533 | AV * CvPADLIST(CV *cv) |
534 | ||
535 | =for hackers | |
dd2155a4 DM |
536 | Found in file pad.c |
537 | ||
538 | =item cv_clone | |
539 | ||
540 | Clone a CV: make a new CV which points to the same code etc, but which | |
ad63d80f | 541 | has a newly-created pad built by copying the prototype pad and capturing |
dd2155a4 DM |
542 | any outer lexicals. |
543 | ||
544 | CV* cv_clone(CV* proto) | |
545 | ||
546 | =for hackers | |
547 | Found in file pad.c | |
548 | ||
549 | =item cv_dump | |
550 | ||
551 | dump the contents of a CV | |
552 | ||
e1ec3a88 | 553 | void cv_dump(const CV *cv, const char *title) |
dd2155a4 DM |
554 | |
555 | =for hackers | |
556 | Found in file pad.c | |
557 | ||
558 | =item do_dump_pad | |
559 | ||
560 | Dump the contents of a padlist | |
561 | ||
562 | void do_dump_pad(I32 level, PerlIO *file, PADLIST *padlist, int full) | |
563 | ||
564 | =for hackers | |
565 | Found in file pad.c | |
566 | ||
567 | =item intro_my | |
568 | ||
569 | "Introduce" my variables to visible status. | |
570 | ||
571 | U32 intro_my() | |
572 | ||
573 | =for hackers | |
574 | Found in file pad.c | |
575 | ||
576 | =item pad_add_anon | |
577 | ||
578 | Add an anon code entry to the current compiling pad | |
579 | ||
580 | PADOFFSET pad_add_anon(SV* sv, OPCODE op_type) | |
581 | ||
582 | =for hackers | |
583 | Found in file pad.c | |
584 | ||
585 | =item pad_add_name | |
586 | ||
b5c19bd7 DM |
587 | Create a new name and associated PADMY SV in the current pad; return the |
588 | offset. | |
dd2155a4 DM |
589 | If C<typestash> is valid, the name is for a typed lexical; set the |
590 | name's stash to that value. | |
591 | If C<ourstash> is valid, it's an our lexical, set the name's | |
592 | GvSTASH to that value | |
593 | ||
dd2155a4 DM |
594 | If fake, it means we're cloning an existing entry |
595 | ||
e1ec3a88 | 596 | PADOFFSET pad_add_name(const char *name, HV* typestash, HV* ourstash, bool clone) |
dd2155a4 DM |
597 | |
598 | =for hackers | |
599 | Found in file pad.c | |
600 | ||
601 | =item pad_alloc | |
602 | ||
603 | Allocate a new my or tmp pad entry. For a my, simply push a null SV onto | |
604 | the end of PL_comppad, but for a tmp, scan the pad from PL_padix upwards | |
605 | for a slot which has no name and and no active value. | |
606 | ||
607 | PADOFFSET pad_alloc(I32 optype, U32 tmptype) | |
608 | ||
609 | =for hackers | |
610 | Found in file pad.c | |
611 | ||
612 | =item pad_block_start | |
613 | ||
614 | Update the pad compilation state variables on entry to a new block | |
615 | ||
616 | void pad_block_start(int full) | |
617 | ||
618 | =for hackers | |
619 | Found in file pad.c | |
620 | ||
621 | =item pad_check_dup | |
622 | ||
623 | Check for duplicate declarations: report any of: | |
624 | * a my in the current scope with the same name; | |
625 | * an our (anywhere in the pad) with the same name and the same stash | |
626 | as C<ourstash> | |
627 | C<is_our> indicates that the name to check is an 'our' declaration | |
628 | ||
e1ec3a88 | 629 | void pad_check_dup(const char* name, bool is_our, const HV* ourstash) |
dd2155a4 DM |
630 | |
631 | =for hackers | |
632 | Found in file pad.c | |
633 | ||
634 | =item pad_findlex | |
635 | ||
636 | Find a named lexical anywhere in a chain of nested pads. Add fake entries | |
b5c19bd7 DM |
637 | in the inner pads if it's found in an outer one. |
638 | ||
639 | Returns the offset in the bottom pad of the lex or the fake lex. | |
640 | cv is the CV in which to start the search, and seq is the current cop_seq | |
641 | to match against. If warn is true, print appropriate warnings. The out_* | |
642 | vars return values, and so are pointers to where the returned values | |
643 | should be stored. out_capture, if non-null, requests that the innermost | |
644 | instance of the lexical is captured; out_name_sv is set to the innermost | |
645 | matched namesv or fake namesv; out_flags returns the flags normally | |
646 | associated with the IVX field of a fake namesv. | |
647 | ||
648 | Note that pad_findlex() is recursive; it recurses up the chain of CVs, | |
649 | then comes back down, adding fake entries as it goes. It has to be this way | |
650 | because fake namesvs in anon protoypes have to store in NVX the index into | |
651 | the parent pad. | |
652 | ||
e1ec3a88 | 653 | 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 |
654 | |
655 | =for hackers | |
656 | Found in file pad.c | |
657 | ||
658 | =item pad_findmy | |
659 | ||
ad63d80f | 660 | Given a lexical name, try to find its offset, first in the current pad, |
dd2155a4 | 661 | or failing that, in the pads of any lexically enclosing subs (including |
ad63d80f JP |
662 | the complications introduced by eval). If the name is found in an outer pad, |
663 | then a fake entry is added to the current pad. | |
dd2155a4 DM |
664 | Returns the offset in the current pad, or NOT_IN_PAD on failure. |
665 | ||
e1ec3a88 | 666 | PADOFFSET pad_findmy(const char* name) |
dd2155a4 DM |
667 | |
668 | =for hackers | |
669 | Found in file pad.c | |
670 | ||
671 | =item pad_fixup_inner_anons | |
672 | ||
673 | For any anon CVs in the pad, change CvOUTSIDE of that CV from | |
7dafbf52 DM |
674 | old_cv to new_cv if necessary. Needed when a newly-compiled CV has to be |
675 | moved to a pre-existing CV struct. | |
dd2155a4 DM |
676 | |
677 | void pad_fixup_inner_anons(PADLIST *padlist, CV *old_cv, CV *new_cv) | |
678 | ||
679 | =for hackers | |
680 | Found in file pad.c | |
681 | ||
682 | =item pad_free | |
683 | ||
684 | Free the SV at offet po in the current pad. | |
685 | ||
686 | void pad_free(PADOFFSET po) | |
687 | ||
688 | =for hackers | |
689 | Found in file pad.c | |
690 | ||
691 | =item pad_leavemy | |
692 | ||
693 | Cleanup at end of scope during compilation: set the max seq number for | |
694 | lexicals in this scope and warn of any lexicals that never got introduced. | |
695 | ||
696 | void pad_leavemy() | |
697 | ||
698 | =for hackers | |
699 | Found in file pad.c | |
700 | ||
701 | =item pad_new | |
702 | ||
ad63d80f | 703 | Create a new compiling padlist, saving and updating the various global |
dd2155a4 DM |
704 | vars at the same time as creating the pad itself. The following flags |
705 | can be OR'ed together: | |
706 | ||
707 | padnew_CLONE this pad is for a cloned CV | |
708 | padnew_SAVE save old globals | |
709 | padnew_SAVESUB also save extra stuff for start of sub | |
710 | ||
c7c737cb | 711 | PADLIST* pad_new(int flags) |
dd2155a4 DM |
712 | |
713 | =for hackers | |
714 | Found in file pad.c | |
715 | ||
716 | =item pad_push | |
717 | ||
718 | Push a new pad frame onto the padlist, unless there's already a pad at | |
26019298 AL |
719 | this depth, in which case don't bother creating a new one. Then give |
720 | the new pad an @_ in slot zero. | |
dd2155a4 | 721 | |
26019298 | 722 | void pad_push(PADLIST *padlist, int depth) |
dd2155a4 DM |
723 | |
724 | =for hackers | |
725 | Found in file pad.c | |
726 | ||
727 | =item pad_reset | |
728 | ||
729 | Mark all the current temporaries for reuse | |
730 | ||
731 | void pad_reset() | |
732 | ||
733 | =for hackers | |
734 | Found in file pad.c | |
735 | ||
736 | =item pad_setsv | |
737 | ||
738 | Set the entry at offset po in the current pad to sv. | |
739 | Use the macro PAD_SETSV() rather than calling this function directly. | |
740 | ||
741 | void pad_setsv(PADOFFSET po, SV* sv) | |
742 | ||
743 | =for hackers | |
744 | Found in file pad.c | |
745 | ||
746 | =item pad_swipe | |
747 | ||
748 | Abandon the tmp in the current pad at offset po and replace with a | |
749 | new one. | |
750 | ||
751 | void pad_swipe(PADOFFSET po, bool refadjust) | |
752 | ||
753 | =for hackers | |
754 | Found in file pad.c | |
755 | ||
756 | =item pad_tidy | |
757 | ||
758 | Tidy up a pad after we've finished compiling it: | |
759 | * remove most stuff from the pads of anonsub prototypes; | |
760 | * give it a @_; | |
761 | * mark tmps as such. | |
762 | ||
763 | void pad_tidy(padtidy_type type) | |
764 | ||
765 | =for hackers | |
766 | Found in file pad.c | |
767 | ||
768 | =item pad_undef | |
769 | ||
770 | Free the padlist associated with a CV. | |
771 | If parts of it happen to be current, we null the relevant | |
772 | PL_*pad* global vars so that we don't have any dangling references left. | |
773 | We also repoint the CvOUTSIDE of any about-to-be-orphaned | |
a3985cdc | 774 | inner subs to the outer of this cv. |
dd2155a4 | 775 | |
7dafbf52 DM |
776 | (This function should really be called pad_free, but the name was already |
777 | taken) | |
778 | ||
a3985cdc | 779 | void pad_undef(CV* cv) |
dd2155a4 DM |
780 | |
781 | =for hackers | |
782 | Found in file pad.c | |
a4f1a029 NIS |
783 | |
784 | ||
785 | =back | |
786 | ||
787 | =head1 Stack Manipulation Macros | |
788 | ||
789 | =over 8 | |
790 | ||
791 | =item djSP | |
792 | ||
793 | Declare Just C<SP>. This is actually identical to C<dSP>, and declares | |
794 | a local copy of perl's stack pointer, available via the C<SP> macro. | |
795 | See C<SP>. (Available for backward source code compatibility with the | |
796 | old (Perl 5.005) thread model.) | |
797 | ||
798 | djSP; | |
799 | ||
800 | =for hackers | |
801 | Found in file pp.h | |
802 | ||
803 | =item LVRET | |
804 | ||
805 | True if this op will be the return value of an lvalue subroutine | |
806 | ||
807 | =for hackers | |
808 | Found in file pp.h | |
809 | ||
810 | ||
811 | =back | |
812 | ||
813 | =head1 SV Manipulation Functions | |
814 | ||
815 | =over 8 | |
816 | ||
29489e7c DM |
817 | =item find_uninit_var |
818 | ||
819 | Find the name of the undefined variable (if any) that caused the operator o | |
820 | to issue a "Use of uninitialized value" warning. | |
821 | If match is true, only return a name if it's value matches uninit_sv. | |
822 | So roughly speaking, if a unary operator (such as OP_COS) generates a | |
823 | warning, then following the direct child of the op may yield an | |
824 | OP_PADSV or OP_GV that gives the name of the undefined variable. On the | |
825 | other hand, with OP_ADD there are two branches to follow, so we only print | |
826 | the variable name if we get an exact match. | |
827 | ||
828 | The name is returned as a mortal SV. | |
829 | ||
830 | Assumes that PL_op is the op that originally triggered the error, and that | |
831 | PL_comppad/PL_curpad points to the currently executing pad. | |
832 | ||
833 | SV* find_uninit_var(OP* obase, SV* uninit_sv, bool top) | |
834 | ||
835 | =for hackers | |
836 | Found in file sv.c | |
837 | ||
a4f1a029 NIS |
838 | =item report_uninit |
839 | ||
840 | Print appropriate "Use of uninitialized variable" warning | |
841 | ||
29489e7c | 842 | void report_uninit(SV* uninit_sv) |
a4f1a029 NIS |
843 | |
844 | =for hackers | |
845 | Found in file sv.c | |
846 | ||
645c22ef DM |
847 | =item sv_add_arena |
848 | ||
849 | Given a chunk of memory, link it to the head of the list of arenas, | |
850 | and split it into a list of free SVs. | |
851 | ||
852 | void sv_add_arena(char* ptr, U32 size, U32 flags) | |
853 | ||
854 | =for hackers | |
855 | Found in file sv.c | |
856 | ||
857 | =item sv_clean_all | |
858 | ||
859 | Decrement the refcnt of each remaining SV, possibly triggering a | |
860 | cleanup. This function may have to be called multiple times to free | |
8fb26106 | 861 | SVs which are in complex self-referential hierarchies. |
645c22ef DM |
862 | |
863 | I32 sv_clean_all() | |
864 | ||
865 | =for hackers | |
866 | Found in file sv.c | |
867 | ||
868 | =item sv_clean_objs | |
869 | ||
870 | Attempt to destroy all objects not yet freed | |
871 | ||
872 | void sv_clean_objs() | |
873 | ||
874 | =for hackers | |
875 | Found in file sv.c | |
876 | ||
877 | =item sv_free_arenas | |
878 | ||
879 | Deallocate the memory used by all arenas. Note that all the individual SV | |
880 | heads and bodies within the arenas must already have been freed. | |
881 | ||
882 | void sv_free_arenas() | |
883 | ||
884 | =for hackers | |
885 | Found in file sv.c | |
886 | ||
a4f1a029 | 887 | |
954c1994 GS |
888 | =back |
889 | ||
890 | =head1 AUTHORS | |
891 | ||
1c846c1f NIS |
892 | The autodocumentation system was originally added to the Perl core by |
893 | Benjamin Stuhl. Documentation is by whoever was kind enough to | |
954c1994 GS |
894 | document their functions. |
895 | ||
896 | =head1 SEE ALSO | |
897 | ||
898 | perlguts(1), perlapi(1) | |
899 |