3 perlintern - autogenerated documentation of purely B<internal>
8 This file is the autogenerated documentation of functions in the
9 Perl interpreter that are documented using Perl's internal documentation
10 format but are not marked as part of the Perl API. In other words,
11 B<they are not for use in extensions>!
14 =head1 Functions in file pad.h
21 Save the current pad in the given context block structure.
23 void CX_CURPAD_SAVE(struct context)
30 Access the SV at offset po in the saved current pad in the given
31 context block structure (can be used as an lvalue).
33 PAD * CX_CURPAD_SV(struct context, PADOFFSET po)
40 Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
42 SV * PAD_BASE_SV (PADLIST padlist, PADOFFSET po)
50 Clone the state variables associated with running and compiling pads.
52 void PAD_CLONE_VARS(PerlInterpreter *proto_perl \)
57 =item PAD_COMPNAME_FLAGS
59 Return the flags for the current compiling pad name
60 at offset C<po>. Assumes a valid slot entry.
62 U32 PAD_COMPNAME_FLAGS(PADOFFSET po)
67 =item PAD_COMPNAME_GEN
69 The generation number of the name at offset C<po> in the current
70 compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose.
72 STRLEN PAD_COMPNAME_GEN(PADOFFSET po)
77 =item PAD_COMPNAME_OURSTASH
79 Return the stash associated with an C<our> variable.
80 Assumes the slot entry is a valid C<our> lexical.
82 HV * PAD_COMPNAME_OURSTASH(PADOFFSET po)
89 Return the name of the current compiling pad name
90 at offset C<po>. Assumes a valid slot entry.
92 char * PAD_COMPNAME_PV(PADOFFSET po)
97 =item PAD_COMPNAME_TYPE
99 Return the type (stash) of the current compiling pad name at offset
100 C<po>. Must be a valid name. Returns null if not typed.
102 HV * PAD_COMPNAME_TYPE(PADOFFSET po)
111 void PAD_DUP(PADLIST dstpad, PADLIST srcpad, CLONE_PARAMS* param)
116 =item PAD_SAVE_SETNULLPAD
118 Save the current pad then set it to null.
120 void PAD_SAVE_SETNULLPAD()
127 Set the slot at offset C<po> in the current pad to C<sv>
129 SV * PAD_SETSV (PADOFFSET po, SV* sv)
136 Set the current pad to be pad C<n> in the padlist, saving
137 the previous current pad.
139 void PAD_SET_CUR (PADLIST padlist, I32 n)
146 Get the value at offset C<po> in the current pad
148 void PAD_SV (PADOFFSET po)
155 Lightweight and lvalue version of C<PAD_SV>.
156 Get or set the value at offset C<po> in the current pad.
157 Unlike C<PAD_SV>, does not print diagnostics with -DX.
158 For internal use only.
160 SV * PAD_SVl (PADOFFSET po)
165 =item PAD_UPDATE_CURPAD
167 Set PL_curpad from the value of PL_comppad.
169 void PAD_UPDATE_CURPAD()
176 Clear the pointed to pad value on scope exit. (ie the runtime action of 'my')
178 void SAVECLEARSV (SV **svp)
185 save PL_comppad and PL_curpad
194 Free the op on scope exit. At the same time, reset PL_curpad
199 void SAVEFREEOP (OP *o)
206 Save a pad slot (used to restore after an iteration)
208 void SAVEPADSV (PADOFFSET po)
216 =head1 Global Variables
222 When Perl is run in debugging mode, with the B<-d> switch, this SV is a
223 boolean which indicates whether subs are being single-stepped.
224 Single-stepping is automatically turned on after every step. This is the C
225 variable which corresponds to Perl's $DB::single variable. See
231 Found in file intrpvar.h
235 When Perl is run in debugging mode, with the B<-d> switch, this GV contains
236 the SV which holds the name of the sub being debugged. This is the C
237 variable which corresponds to Perl's $DB::sub variable. See
243 Found in file intrpvar.h
247 Trace variable used when Perl is run in debugging mode, with the B<-d>
248 switch. This is the C variable which corresponds to Perl's $DB::trace
249 variable. See C<PL_DBsingle>.
254 Found in file intrpvar.h
258 The C variable which corresponds to Perl's $^W warning variable.
263 Found in file intrpvar.h
267 The GV which was last used for a filehandle input operation. (C<< <FH> >>)
272 Found in file thrdvar.h
276 The output field separator - C<$,> in Perl space.
281 Found in file thrdvar.h
285 The input record separator - C<$/> in Perl space.
290 Found in file thrdvar.h
301 Returns C<TRUE> if given the name of a magical GV.
303 Currently only useful internally when determining if a GV should be
304 created even in rvalue contexts.
306 C<flags> is not used at present but available for future extension to
307 allow selecting particular classes of magical variable.
309 bool is_gv_magical(char *name, STRLEN len, U32 flags)
323 Function called by C<do_readline> to spawn a glob (or do the glob inside
324 perl on VMS). This code used to be inline, but now perl uses C<File::Glob>
325 this glob starter is only used by miniperl during the build process.
326 Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up.
328 PerlIO* start_glob(SV* pattern, IO *io)
336 =head1 Pad Data Structures
342 CV's can have CvPADLIST(cv) set to point to an AV.
344 For these purposes "forms" are a kind-of CV, eval""s are too (except they're
345 not callable at will and are always thrown away after the eval"" is done
348 XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad,
349 but that is really the callers pad (a slot of which is allocated by
352 The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items
353 is managed "manual" (mostly in op.c) rather than normal av.c rules.
354 The items in the AV are not SVs as for a normal AV, but other AVs:
356 0'th Entry of the CvPADLIST is an AV which represents the "names" or rather
357 the "static type information" for lexicals.
359 The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that
360 depth of recursion into the CV.
361 The 0'th slot of a frame AV is an AV which is @_.
362 other entries are storage for variables and op targets.
365 C<PL_comppad_name> is set the the the names AV.
366 C<PL_comppad> is set the the frame AV for the frame CvDEPTH == 1.
367 C<PL_curpad> is set the body of the frame AV (i.e. AvARRAY(PL_comppad)).
369 Itterating over the names AV itterates over all possible pad
370 items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having
371 &PL_sv_undef "names" (see pad_alloc()).
373 Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names.
374 The rest are op targets/GVs/constants which are statically allocated
375 or resolved at compile time. These don't have names by which they
376 can be looked up from Perl code at run time through eval"" like
377 my/our variables can be. Since they can't be looked up by "name"
378 but only by their index allocated at compile time (which is usually
379 in PL_op->op_targ), wasting a name SV for them doesn't make sense.
381 The SVs in the names AV have their PV being the name of the variable.
382 NV+1..IV inclusive is a range of cop_seq numbers for which the name is
383 valid. For typed lexicals name SV is SVt_PVMG and SvSTASH points at the
384 type. For C<our> lexicals, the type is SVt_PVGV, and GvSTASH points at the
385 stash of the associated global (so that duplicate C<our> delarations in the
386 same package can be detected). SvCUR is sometimes hijacked to
387 store the generation number during compilation.
389 If SvFAKE is set on the name SV then slot in the frame AVs are
390 a REFCNT'ed references to a lexical from "outside".
392 If the 'name' is '&' the the corresponding entry in frame AV
393 is a CV representing a possible closure.
394 (SvFAKE and name of '&' is not a meaningful combination currently but could
395 become so if C<my sub foo {}> is implemented.)
397 AV * CvPADLIST(CV *cv)
404 Clone a CV: make a new CV which points to the same code etc, but which
405 has a newly-created pad done by copying the prototype pad and capturing
408 CV* cv_clone(CV* proto)
415 dump the contents of a CV
417 void cv_dump(CV *cv, char *title)
424 Dump the contents of a padlist
426 void do_dump_pad(I32 level, PerlIO *file, PADLIST *padlist, int full)
433 "Introduce" my variables to visible status.
442 Add an anon code entry to the current compiling pad
444 PADOFFSET pad_add_anon(SV* sv, OPCODE op_type)
451 Create a new name in the current pad at the specified offset.
452 If C<typestash> is valid, the name is for a typed lexical; set the
453 name's stash to that value.
454 If C<ourstash> is valid, it's an our lexical, set the name's
455 GvSTASH to that value
457 Also, if the name is @.. or %.., create a new array or hash for that slot
459 If fake, it means we're cloning an existing entry
461 PADOFFSET pad_add_name(char *name, HV* typestash, HV* ourstash, bool clone)
468 Allocate a new my or tmp pad entry. For a my, simply push a null SV onto
469 the end of PL_comppad, but for a tmp, scan the pad from PL_padix upwards
470 for a slot which has no name and and no active value.
472 PADOFFSET pad_alloc(I32 optype, U32 tmptype)
477 =item pad_block_start
479 Update the pad compilation state variables on entry to a new block
481 void pad_block_start(int full)
488 Check for duplicate declarations: report any of:
489 * a my in the current scope with the same name;
490 * an our (anywhere in the pad) with the same name and the same stash
492 C<is_our> indicates that the name to check is an 'our' declaration
495 void pad_check_dup(char* name, bool is_our, HV* ourstash)
502 Find a named lexical anywhere in a chain of nested pads. Add fake entries
503 in the inner pads if its found in an outer one.
505 If flags == FINDLEX_NOSEARCH we don't bother searching outer contexts.
507 PADOFFSET pad_findlex(char* name, PADOFFSET newoff, U32 seq, CV* startcv, I32 cx_ix, I32 saweval, U32 flags)
514 Given a lexical name, try to find it's offset, first in the current pad,
515 or failing that, in the pads of any lexically enclosing subs (including
516 the complications introduced by eval). If the name is found in an outer pad, then a fake entry is added to the current pad.
517 Returns the offset in the current pad, or NOT_IN_PAD on failure.
519 PADOFFSET pad_findmy(char* name)
524 =item pad_fixup_inner_anons
526 For any anon CVs in the pad, change CvOUTSIDE of that CV from
527 old_cv to new_cv if necessary.
529 void pad_fixup_inner_anons(PADLIST *padlist, CV *old_cv, CV *new_cv)
536 Free the SV at offet po in the current pad.
538 void pad_free(PADOFFSET po)
545 Cleanup at end of scope during compilation: set the max seq number for
546 lexicals in this scope and warn of any lexicals that never got introduced.
555 Create a new comnpiling padlist, saving and updating the various global
556 vars at the same time as creating the pad itself. The following flags
557 can be OR'ed together:
559 padnew_CLONE this pad is for a cloned CV
560 padnew_SAVE save old globals
561 padnew_SAVESUB also save extra stuff for start of sub
563 PADLIST* pad_new(padnew_flags flags)
570 Push a new pad frame onto the padlist, unless there's already a pad at
571 this depth, in which case don't bother creating a new one.
572 If has_args is true, give the new pad an @_ in slot zero.
574 void pad_push(PADLIST *padlist, int depth, int has_args)
581 Mark all the current temporaries for reuse
590 Set the entry at offset po in the current pad to sv.
591 Use the macro PAD_SETSV() rather than calling this function directly.
593 void pad_setsv(PADOFFSET po, SV* sv)
600 Abandon the tmp in the current pad at offset po and replace with a
603 void pad_swipe(PADOFFSET po, bool refadjust)
610 Tidy up a pad after we've finished compiling it:
611 * remove most stuff from the pads of anonsub prototypes;
615 void pad_tidy(padtidy_type type)
622 Free the padlist associated with a CV.
623 If parts of it happen to be current, we null the relevant
624 PL_*pad* global vars so that we don't have any dangling references left.
625 We also repoint the CvOUTSIDE of any about-to-be-orphaned
626 inner subs to outercv.
628 void pad_undef(CV* cv, CV* outercv)
636 =head1 Stack Manipulation Macros
642 Declare Just C<SP>. This is actually identical to C<dSP>, and declares
643 a local copy of perl's stack pointer, available via the C<SP> macro.
644 See C<SP>. (Available for backward source code compatibility with the
645 old (Perl 5.005) thread model.)
654 True if this op will be the return value of an lvalue subroutine
662 =head1 SV Manipulation Functions
668 Print appropriate "Use of uninitialized variable" warning
677 Given a chunk of memory, link it to the head of the list of arenas,
678 and split it into a list of free SVs.
680 void sv_add_arena(char* ptr, U32 size, U32 flags)
687 Decrement the refcnt of each remaining SV, possibly triggering a
688 cleanup. This function may have to be called multiple times to free
689 SVs which are in complex self-referential hierarchies.
698 Attempt to destroy all objects not yet freed
707 Deallocate the memory used by all arenas. Note that all the individual SV
708 heads and bodies within the arenas must already have been freed.
710 void sv_free_arenas()
720 The autodocumentation system was originally added to the Perl core by
721 Benjamin Stuhl. Documentation is by whoever was kind enough to
722 document their functions.
726 perlguts(1), perlapi(1)