3 * Copyright (C) 2002, 2003, 2005, 2006, 2007, 2008,
4 * 2009, 2010, 2011 by Larry Wall and others
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.
9 * This file defines the types and macros associated with the API for
10 * manipulating scratchpads, which are used by perl to store lexical
11 * variables, op targets and constants.
15 =for apidoc_section Pad Data Structures
19 /* offsets within a pad */
21 typedef SSize_t PADOFFSET; /* signed so that -1 is a valid value */
22 #define NOT_IN_PAD ((PADOFFSET) -1)
24 /* B.xs expects the first members of these two structs to line up
25 (xpadl_max with xpadnl_fill).
29 SSize_t xpadl_max; /* max index for which array has space */
31 PAD ** xpadlarr_alloc; /* Pointer to beginning of array of AVs.
32 index 0 is a padnamelist * */
35 PAD * pad_1; /* this slice of PAD * array always alloced */
36 PAD * pad_2; /* maybe unalloced */
37 } * xpadlarr_dbg; /* for use with a C debugger only */
39 U32 xpadl_id; /* Semi-unique ID, shared between clones */
40 U32 xpadl_outid; /* ID of outer pad */
44 SSize_t xpadnl_fill; /* max index in use */
45 PADNAME ** xpadnl_alloc; /* pointer to beginning of array */
46 SSize_t xpadnl_max; /* max index for which array has space */
47 PADOFFSET xpadnl_max_named; /* highest index with len > 0 */
51 /* PERL_PADNAME_MINIMAL uses less memory, but on some platforms
52 PERL_PADNAME_ALIGNED may be faster, so platform-specific hints can
53 define one or the other. */
54 #if defined(PERL_PADNAME_MINIMAL) && defined (PERL_PADNAME_ALIGNED)
55 # error PERL_PADNAME_MINIMAL and PERL_PADNAME_ALIGNED are exclusive
58 #if !defined(PERL_PADNAME_MINIMAL) && !defined(PERL_PADNAME_ALIGNED)
59 # define PERL_PADNAME_MINIMAL
62 #define _PADNAME_BASE \
64 HV * xpadn_ourstash; \
66 HV * xpadn_typestash; \
80 struct padname_with_str {
81 #ifdef PERL_PADNAME_MINIMAL
84 struct padname xpadn_padname;
91 #define PADNAME_FROM_PV(s) \
92 ((PADNAME *)((s) - STRUCT_OFFSET(struct padname_with_str, xpadn_str)))
95 /* a value that PL_cop_seqmax is guaranteed never to be,
96 * flagging that a lexical is being introduced, or has not yet left scope
98 #define PERL_PADSEQ_INTRO U32_MAX
99 #define COP_SEQMAX_INC \
101 (void)(PL_cop_seqmax == PERL_PADSEQ_INTRO && PL_cop_seqmax++))
104 /* B.xs needs these for the benefit of B::Deparse */
105 /* Low range end is exclusive (valid from the cop seq after this one) */
106 /* High range end is inclusive (valid up to this cop seq) */
108 #define COP_SEQ_RANGE_LOW(pn) (pn)->xpadn_low
109 #define COP_SEQ_RANGE_HIGH(pn) (pn)->xpadn_high
110 #define PARENT_PAD_INDEX(pn) (pn)->xpadn_low
111 #define PARENT_FAKELEX_FLAGS(pn) (pn)->xpadn_high
113 /* Flags set in the SvIVX field of FAKE namesvs */
115 #define PAD_FAKELEX_ANON 1 /* the lex is declared in an ANON, or ... */
116 #define PAD_FAKELEX_MULTI 2 /* the lex can be instantiated multiple times */
118 /* flags for the pad_new() function */
120 #define padnew_CLONE 1 /* this pad is for a cloned CV */
121 #define padnew_SAVE 2 /* save old globals */
122 #define padnew_SAVESUB 4 /* also save extra stuff for start of sub */
124 /* values for the pad_tidy() function */
127 padtidy_SUB, /* tidy up a pad for a sub, */
128 padtidy_SUBCLONE, /* a cloned sub, */
129 padtidy_FORMAT /* or a format */
132 /* flags for pad_add_name_pvn. */
134 #define padadd_OUR 0x01 /* our declaration. */
135 #define padadd_STATE 0x02 /* state declaration. */
136 #define padadd_NO_DUP_CHECK 0x04 /* skip warning on dups. */
137 #define padadd_STALEOK 0x08 /* allow stale lexical in active
138 * sub, but only one level up */
140 /* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine
141 * whether PL_comppad and PL_curpad are consistent and whether they have
144 # define pad_peg(label)
147 # define ASSERT_CURPAD_LEGAL(label) \
149 if (PL_comppad ? (AvARRAY(PL_comppad) != PL_curpad) : (PL_curpad != 0)) \
150 Perl_croak(aTHX_ "panic: illegal pad in %s: 0x%" UVxf "[0x%" UVxf "]",\
151 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
154 # define ASSERT_CURPAD_ACTIVE(label) \
156 if (!PL_comppad || (AvARRAY(PL_comppad) != PL_curpad)) \
157 Perl_croak(aTHX_ "panic: invalid pad in %s: 0x%" UVxf "[0x%" UVxf "]",\
158 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
160 # define ASSERT_CURPAD_LEGAL(label)
161 # define ASSERT_CURPAD_ACTIVE(label)
166 /* Note: the following three macros are actually defined in scope.h, but
167 * they are documented here for completeness, since they directly or
168 * indirectly affect pads.
170 =for apidoc m|void|SAVEPADSV |PADOFFSET po
171 Save a pad slot (used to restore after an iteration)
175 XXX DAPM it would make more sense to make the arg a PADOFFSET
177 =for apidoc m|void|SAVECLEARSV |SV **svp
178 Clear the pointed to pad value on scope exit. (i.e. the runtime action of
181 =for apidoc m|void|SAVECOMPPAD
182 save C<PL_comppad> and C<PL_curpad>
185 =for apidoc Amx|PAD **|PadlistARRAY|PADLIST * padlist
186 The C array of a padlist, containing the pads. Only subscript it with
187 numbers >= 1, as the 0th entry is not guaranteed to remain usable.
189 =for apidoc Amx|SSize_t|PadlistMAX|PADLIST * padlist
190 The index of the last allocated space in the padlist. Note that the last
191 pad may be in an earlier slot. Any entries following it will be C<NULL> in
194 =for apidoc Amx|PADNAMELIST *|PadlistNAMES|PADLIST * padlist
195 The names associated with pad entries.
197 =for apidoc Amx|PADNAME **|PadlistNAMESARRAY|PADLIST * padlist
198 The C array of pad names.
200 =for apidoc Amx|SSize_t|PadlistNAMESMAX|PADLIST * padlist
201 The index of the last pad name.
203 =for apidoc Amx|U32|PadlistREFCNT|PADLIST * padlist
204 The reference count of the padlist. Currently this is always 1.
206 =for apidoc Amx|PADNAME **|PadnamelistARRAY|PADNAMELIST * pnl
207 The C array of pad names.
209 =for apidoc Amx|SSize_t|PadnamelistMAX|PADNAMELIST * pnl
210 The index of the last pad name.
212 =for apidoc Amx|SSize_t|PadnamelistREFCNT|PADNAMELIST * pnl
213 The reference count of the pad name list.
215 =for apidoc Amx|void|PadnamelistREFCNT_dec|PADNAMELIST * pnl
216 Lowers the reference count of the pad name list.
218 =for apidoc Amx|SV **|PadARRAY|PAD * pad
219 The C array of pad entries.
221 =for apidoc Amx|SSize_t|PadMAX|PAD * pad
222 The index of the last pad entry.
224 =for apidoc Amx|char *|PadnamePV|PADNAME * pn
225 The name stored in the pad name struct. This returns C<NULL> for a target
228 =for apidoc Amx|STRLEN|PadnameLEN|PADNAME * pn
229 The length of the name.
231 =for apidoc Amx|bool|PadnameUTF8|PADNAME * pn
232 Whether PadnamePV is in UTF-8. Currently, this is always true.
234 =for apidoc Amx|SV *|PadnameSV|PADNAME * pn
235 Returns the pad name as a mortal SV.
237 =for apidoc m|bool|PadnameIsOUR|PADNAME * pn
238 Whether this is an "our" variable.
240 =for apidoc m|HV *|PadnameOURSTASH
241 The stash in which this "our" variable was declared.
243 =for apidoc m|bool|PadnameOUTER|PADNAME * pn
244 Whether this entry belongs to an outer pad. Entries for which this is true
245 are often referred to as 'fake'.
247 =for apidoc m|bool|PadnameIsSTATE|PADNAME * pn
248 Whether this is a "state" variable.
250 =for apidoc m|HV *|PadnameTYPE|PADNAME * pn
251 The stash associated with a typed lexical. This returns the C<%Foo::> hash
254 =for apidoc Amx|SSize_t|PadnameREFCNT|PADNAME * pn
255 The reference count of the pad name.
257 =for apidoc Amx|void|PadnameREFCNT_dec|PADNAME * pn
258 Lowers the reference count of the pad name.
261 =for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv
262 Set the slot at offset C<po> in the current pad to C<sv>
264 =for apidoc m|SV *|PAD_SV |PADOFFSET po
265 Get the value at offset C<po> in the current pad
267 =for apidoc m|SV *|PAD_SVl |PADOFFSET po
268 Lightweight and lvalue version of C<PAD_SV>.
269 Get or set the value at offset C<po> in the current pad.
270 Unlike C<PAD_SV>, does not print diagnostics with -DX.
271 For internal use only.
273 =for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po
274 Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
276 =for apidoc m|void|PAD_SET_CUR |PADLIST padlist|I32 n
277 Set the current pad to be pad C<n> in the padlist, saving
278 the previous current pad. NB currently this macro expands to a string too
279 long for some compilers, so it's best to replace it with
282 PAD_SET_CUR_NOSAVE(padlist,n);
285 =for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n
286 like PAD_SET_CUR, but without the save
288 =for apidoc m|void|PAD_SAVE_SETNULLPAD
289 Save the current pad then set it to null.
291 =for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad
292 Save the current pad to the local variable C<opad>, then make the
293 current pad equal to C<npad>
295 =for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad
296 Restore the old pad saved into the local variable C<opad> by C<PAD_SAVE_LOCAL()>
301 #define PadlistARRAY(pl) (pl)->xpadl_arr.xpadlarr_alloc
302 #define PadlistMAX(pl) (pl)->xpadl_max
303 #define PadlistNAMES(pl) *((PADNAMELIST **)PadlistARRAY(pl))
304 #define PadlistNAMESARRAY(pl) PadnamelistARRAY(PadlistNAMES(pl))
305 #define PadlistNAMESMAX(pl) PadnamelistMAX(PadlistNAMES(pl))
306 #define PadlistREFCNT(pl) 1 /* reserved for future use */
308 #define PadnamelistARRAY(pnl) (pnl)->xpadnl_alloc
309 #define PadnamelistMAX(pnl) (pnl)->xpadnl_fill
310 #define PadnamelistMAXNAMED(pnl) (pnl)->xpadnl_max_named
311 #define PadnamelistREFCNT(pnl) (pnl)->xpadnl_refcnt
312 #define PadnamelistREFCNT_dec(pnl) Perl_padnamelist_free(aTHX_ pnl)
314 #define PadARRAY(pad) AvARRAY(pad)
315 #define PadMAX(pad) AvFILLp(pad)
317 #define PadnamePV(pn) (pn)->xpadn_pv
318 #define PadnameLEN(pn) (pn)->xpadn_len
319 #define PadnameUTF8(pn) 1
320 #define PadnameSV(pn) \
321 newSVpvn_flags(PadnamePV(pn), PadnameLEN(pn), SVs_TEMP|SVf_UTF8)
322 #define PadnameFLAGS(pn) (pn)->xpadn_flags
323 #define PadnameIsOUR(pn) (!!(pn)->xpadn_ourstash)
324 #define PadnameOURSTASH(pn) (pn)->xpadn_ourstash
325 #define PadnameTYPE(pn) (pn)->xpadn_type_u.xpadn_typestash
326 #define PadnamePROTOCV(pn) (pn)->xpadn_type_u.xpadn_protocv
327 #define PadnameREFCNT(pn) (pn)->xpadn_refcnt
328 #define PadnameREFCNT_dec(pn) Perl_padname_free(aTHX_ pn)
329 #define PadnameOURSTASH_set(pn,s) (PadnameOURSTASH(pn) = (s))
330 #define PadnameTYPE_set(pn,s) (PadnameTYPE(pn) = (s))
331 #define PadnameOUTER(pn) (PadnameFLAGS(pn) & PADNAMEt_OUTER)
332 #define PadnameIsSTATE(pn) (PadnameFLAGS(pn) & PADNAMEt_STATE)
333 #define PadnameLVALUE(pn) (PadnameFLAGS(pn) & PADNAMEt_LVALUE)
335 #define PadnameLVALUE_on(pn) (PadnameFLAGS(pn) |= PADNAMEt_LVALUE)
336 #define PadnameIsSTATE_on(pn) (PadnameFLAGS(pn) |= PADNAMEt_STATE)
338 #define PADNAMEt_OUTER 1 /* outer lexical var */
339 #define PADNAMEt_STATE 2 /* state var */
340 #define PADNAMEt_LVALUE 4 /* used as lvalue */
341 #define PADNAMEt_TYPED 8 /* for B; unused by core */
342 #define PADNAMEt_OUR 16 /* for B; unused by core */
344 /* backward compatibility */
345 #define SvPAD_STATE PadnameIsSTATE
346 #define SvPAD_TYPED(pn) (!!PadnameTYPE(pn))
347 #define SvPAD_OUR(pn) (!!PadnameOURSTASH(pn))
348 #define SvPAD_STATE_on PadnameIsSTATE_on
349 #define SvPAD_TYPED_on(pn) (PadnameFLAGS(pn) |= PADNAMEt_TYPED)
350 #define SvPAD_OUR_on(pn) (PadnameFLAGS(pn) |= PADNAMEt_OUR)
351 #define SvOURSTASH PadnameOURSTASH
352 #define SvOURSTASH_set PadnameOURSTASH_set
353 #define SVpad_STATE PADNAMEt_STATE
354 #define SVpad_TYPED PADNAMEt_TYPED
355 #define SVpad_OUR PADNAMEt_OUR
358 # define PAD_SV(po) pad_sv(po)
359 # define PAD_SETSV(po,sv) pad_setsv(po,sv)
361 # define PAD_SV(po) (PL_curpad[po])
362 # define PAD_SETSV(po,sv) PL_curpad[po] = (sv)
365 #define PAD_SVl(po) (PL_curpad[po])
367 #define PAD_BASE_SV(padlist, po) \
368 (PadlistARRAY(padlist)[1]) \
369 ? AvARRAY(MUTABLE_AV((PadlistARRAY(padlist)[1])))[po] \
373 #define PAD_SET_CUR_NOSAVE(padlist,nth) \
374 PL_comppad = (PAD*) (PadlistARRAY(padlist)[nth]); \
375 PL_curpad = AvARRAY(PL_comppad); \
376 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
377 "Pad 0x%" UVxf "[0x%" UVxf "] set_cur depth=%d\n", \
378 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(nth)));
381 #define PAD_SET_CUR(padlist,nth) \
383 PAD_SET_CUR_NOSAVE(padlist,nth);
386 #define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \
387 PL_comppad = NULL; PL_curpad = NULL; \
388 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n"));
390 #define PAD_SAVE_LOCAL(opad,npad) \
392 PL_comppad = (npad); \
393 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
394 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
395 "Pad 0x%" UVxf "[0x%" UVxf "] save_local\n", \
396 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
398 #define PAD_RESTORE_LOCAL(opad) \
399 assert(!opad || !SvIS_FREED(opad)); \
401 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
402 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
403 "Pad 0x%" UVxf "[0x%" UVxf "] restore_local\n", \
404 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
408 =for apidoc m|void|CX_CURPAD_SAVE|struct context
409 Save the current pad in the given context block structure.
411 =for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po
412 Access the SV at offset C<po> in the saved current pad in the given
413 context block structure (can be used as an lvalue).
418 #define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad
419 #define CX_CURPAD_SV(block,po) (AvARRAY(MUTABLE_AV(((block).oldcomppad)))[po])
423 =for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po
424 Return the flags for the current compiling pad name
425 at offset C<po>. Assumes a valid slot entry.
427 =for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po
428 Return the name of the current compiling pad name
429 at offset C<po>. Assumes a valid slot entry.
431 =for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po
432 Return the type (stash) of the current compiling pad name at offset
433 C<po>. Must be a valid name. Returns null if not typed.
435 =for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po
436 Return the stash associated with an C<our> variable.
437 Assumes the slot entry is a valid C<our> lexical.
439 =for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po
440 The generation number of the name at offset C<po> in the current
441 compiling pad (lvalue).
443 =for apidoc m|STRLEN|PAD_COMPNAME_GEN_set|PADOFFSET po|int gen
444 Sets the generation number of the name at offset C<po> in the current
445 ling pad (lvalue) to C<gen>.
450 #define PAD_COMPNAME(po) PAD_COMPNAME_SV(po)
451 #define PAD_COMPNAME_SV(po) (PadnamelistARRAY(PL_comppad_name)[(po)])
452 #define PAD_COMPNAME_FLAGS(po) PadnameFLAGS(PAD_COMPNAME(po))
453 #define PAD_COMPNAME_FLAGS_isOUR(po) SvPAD_OUR(PAD_COMPNAME_SV(po))
454 #define PAD_COMPNAME_PV(po) PadnamePV(PAD_COMPNAME(po))
456 #define PAD_COMPNAME_TYPE(po) PadnameTYPE(PAD_COMPNAME(po))
458 #define PAD_COMPNAME_OURSTASH(po) \
459 (SvOURSTASH(PAD_COMPNAME_SV(po)))
461 #define PAD_COMPNAME_GEN(po) \
462 ((STRLEN)PadnamelistARRAY(PL_comppad_name)[po]->xpadn_gen)
464 #define PAD_COMPNAME_GEN_set(po, gen) \
465 (PadnamelistARRAY(PL_comppad_name)[po]->xpadn_gen = (gen))
469 =for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl|CLONE_PARAMS* param
470 Clone the state variables associated with running and compiling pads.
475 /* NB - we set PL_comppad to null unless it points at a value that
476 * has already been dup'ed, ie it points to part of an active padlist.
477 * Otherwise PL_comppad ends up being a leaked scalar in code like
479 * threads->create(sub { threads->create(sub {...} ) } );
480 * where the second thread dups the outer sub's comppad but not the
481 * sub's CV or padlist. */
483 #define PAD_CLONE_VARS(proto_perl, param) \
484 PL_comppad = av_dup(proto_perl->Icomppad, param); \
485 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
487 padnamelist_dup(proto_perl->Icomppad_name, param); \
488 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \
489 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \
490 PL_min_intro_pending = proto_perl->Imin_intro_pending; \
491 PL_max_intro_pending = proto_perl->Imax_intro_pending; \
492 PL_padix = proto_perl->Ipadix; \
493 PL_padix_floor = proto_perl->Ipadix_floor; \
494 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \
495 PL_cop_seqmax = proto_perl->Icop_seqmax;
498 =for apidoc Am|PADOFFSET|pad_add_name_pvs|"name"|U32 flags|HV *typestash|HV *ourstash
500 Exactly like L</pad_add_name_pvn>, but takes a literal string
501 instead of a string/length pair.
506 #define pad_add_name_pvs(name,flags,typestash,ourstash) \
507 Perl_pad_add_name_pvn(aTHX_ STR_WITH_LEN(name), flags, typestash, ourstash)
510 =for apidoc Am|PADOFFSET|pad_findmy_pvs|"name"|U32 flags
512 Exactly like L</pad_findmy_pvn>, but takes a literal string
513 instead of a string/length pair.
518 #define pad_findmy_pvs(name,flags) \
519 Perl_pad_findmy_pvn(aTHX_ STR_WITH_LEN(name), flags)
522 * ex: set ts=8 sts=4 sw=4 et: