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 =head1 Pad Data Structures
19 /* offsets within a pad */
22 typedef U32TYPE PADOFFSET;
25 typedef U64TYPE PADOFFSET;
28 #define NOT_IN_PAD ((PADOFFSET) -1)
30 /* a value that PL_cop_seqmax is guaranteed never to be,
31 * flagging that a lexical is being introduced, or has not yet left scope
33 #define PERL_PADSEQ_INTRO U32_MAX
36 /* B.xs needs these for the benefit of B::Deparse */
37 /* Low range end is exclusive (valid from the cop seq after this one) */
38 /* High range end is inclusive (valid up to this cop seq) */
40 #if defined (DEBUGGING) && defined(__GNUC__) && !defined(PERL_GCC_BRACE_GROUPS_FORBIDDEN)
41 # define COP_SEQ_RANGE_LOW(sv) \
42 (({ const SV *const _sv_cop_seq_range_low = (const SV *) (sv); \
43 assert(SvTYPE(_sv_cop_seq_range_low) == SVt_NV \
44 || SvTYPE(_sv_cop_seq_range_low) >= SVt_PVNV); \
45 assert(SvTYPE(_sv_cop_seq_range_low) != SVt_PVAV); \
46 assert(SvTYPE(_sv_cop_seq_range_low) != SVt_PVHV); \
47 assert(SvTYPE(_sv_cop_seq_range_low) != SVt_PVCV); \
48 assert(SvTYPE(_sv_cop_seq_range_low) != SVt_PVFM); \
49 assert(!isGV_with_GP(_sv_cop_seq_range_low)); \
50 ((XPVNV*) MUTABLE_PTR(SvANY(_sv_cop_seq_range_low)))->xnv_u.xpad_cop_seq.xlow; \
52 # define COP_SEQ_RANGE_HIGH(sv) \
53 (({ const SV *const _sv_cop_seq_range_high = (const SV *) (sv); \
54 assert(SvTYPE(_sv_cop_seq_range_high) == SVt_NV \
55 || SvTYPE(_sv_cop_seq_range_high) >= SVt_PVNV); \
56 assert(SvTYPE(_sv_cop_seq_range_high) != SVt_PVAV); \
57 assert(SvTYPE(_sv_cop_seq_range_high) != SVt_PVHV); \
58 assert(SvTYPE(_sv_cop_seq_range_high) != SVt_PVCV); \
59 assert(SvTYPE(_sv_cop_seq_range_high) != SVt_PVFM); \
60 assert(!isGV_with_GP(_sv_cop_seq_range_high)); \
61 ((XPVNV*) MUTABLE_PTR(SvANY(_sv_cop_seq_range_high)))->xnv_u.xpad_cop_seq.xhigh; \
63 # define PARENT_PAD_INDEX(sv) \
64 (({ const SV *const _sv_parent_pad_index = (const SV *) (sv); \
65 assert(SvTYPE(_sv_parent_pad_index) == SVt_NV \
66 || SvTYPE(_sv_parent_pad_index) >= SVt_PVNV); \
67 assert(SvTYPE(_sv_parent_pad_index) != SVt_PVAV); \
68 assert(SvTYPE(_sv_parent_pad_index) != SVt_PVHV); \
69 assert(SvTYPE(_sv_parent_pad_index) != SVt_PVCV); \
70 assert(SvTYPE(_sv_parent_pad_index) != SVt_PVFM); \
71 assert(!isGV_with_GP(_sv_parent_pad_index)); \
72 ((XPVNV*) MUTABLE_PTR(SvANY(_sv_parent_pad_index)))->xnv_u.xpad_cop_seq.xlow; \
74 # define PARENT_FAKELEX_FLAGS(sv) \
75 (({ const SV *const _sv_parent_fakelex_flags = (const SV *) (sv); \
76 assert(SvTYPE(_sv_parent_fakelex_flags) == SVt_NV \
77 || SvTYPE(_sv_parent_fakelex_flags) >= SVt_PVNV); \
78 assert(SvTYPE(_sv_parent_fakelex_flags) != SVt_PVAV); \
79 assert(SvTYPE(_sv_parent_fakelex_flags) != SVt_PVHV); \
80 assert(SvTYPE(_sv_parent_fakelex_flags) != SVt_PVCV); \
81 assert(SvTYPE(_sv_parent_fakelex_flags) != SVt_PVFM); \
82 assert(!isGV_with_GP(_sv_parent_fakelex_flags)); \
83 ((XPVNV*) MUTABLE_PTR(SvANY(_sv_parent_fakelex_flags)))->xnv_u.xpad_cop_seq.xhigh; \
86 # define COP_SEQ_RANGE_LOW(sv) \
87 (0 + (((XPVNV*) SvANY(sv))->xnv_u.xpad_cop_seq.xlow))
88 # define COP_SEQ_RANGE_HIGH(sv) \
89 (0 + (((XPVNV*) SvANY(sv))->xnv_u.xpad_cop_seq.xhigh))
92 # define PARENT_PAD_INDEX(sv) \
93 (0 + (((XPVNV*) SvANY(sv))->xnv_u.xpad_cop_seq.xlow))
94 # define PARENT_FAKELEX_FLAGS(sv) \
95 (0 + (((XPVNV*) SvANY(sv))->xnv_u.xpad_cop_seq.xhigh))
98 /* Flags set in the SvIVX field of FAKE namesvs */
100 #define PAD_FAKELEX_ANON 1 /* the lex is declared in an ANON, or ... */
101 #define PAD_FAKELEX_MULTI 2 /* the lex can be instantiated multiple times */
103 /* flags for the pad_new() function */
105 #define padnew_CLONE 1 /* this pad is for a cloned CV */
106 #define padnew_SAVE 2 /* save old globals */
107 #define padnew_SAVESUB 4 /* also save extra stuff for start of sub */
109 /* values for the pad_tidy() function */
112 padtidy_SUB, /* tidy up a pad for a sub, */
113 padtidy_SUBCLONE, /* a cloned sub, */
114 padtidy_FORMAT /* or a format */
117 /* flags for pad_add_name_pvn. */
119 #define padadd_OUR 0x01 /* our declaration. */
120 #define padadd_STATE 0x02 /* state declaration. */
121 #define padadd_NO_DUP_CHECK 0x04 /* skip warning on dups. */
122 #define padadd_STALEOK 0x08 /* allow stale lexical in active
123 * sub, but only one level up */
124 #define padadd_UTF8_NAME SVf_UTF8 /* name is UTF-8 encoded. */
126 /* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine
127 * whether PL_comppad and PL_curpad are consistent and whether they have
131 # define pad_peg(label)
135 # define ASSERT_CURPAD_LEGAL(label) \
137 if (PL_comppad ? (AvARRAY(PL_comppad) != PL_curpad) : (PL_curpad != 0)) \
138 Perl_croak(aTHX_ "panic: illegal pad in %s: 0x%"UVxf"[0x%"UVxf"]",\
139 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
142 # define ASSERT_CURPAD_ACTIVE(label) \
144 if (!PL_comppad || (AvARRAY(PL_comppad) != PL_curpad)) \
145 Perl_croak(aTHX_ "panic: invalid pad in %s: 0x%"UVxf"[0x%"UVxf"]",\
146 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
148 # define ASSERT_CURPAD_LEGAL(label)
149 # define ASSERT_CURPAD_ACTIVE(label)
154 /* Note: the following three macros are actually defined in scope.h, but
155 * they are documented here for completeness, since they directly or
156 * indirectly affect pads.
158 =for apidoc m|void|SAVEPADSV |PADOFFSET po
159 Save a pad slot (used to restore after an iteration)
161 XXX DAPM it would make more sense to make the arg a PADOFFSET
162 =for apidoc m|void|SAVECLEARSV |SV **svp
163 Clear the pointed to pad value on scope exit. (i.e. the runtime action of 'my')
165 =for apidoc m|void|SAVECOMPPAD
166 save PL_comppad and PL_curpad
172 =for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv
173 Set the slot at offset C<po> in the current pad to C<sv>
175 =for apidoc m|void|PAD_SV |PADOFFSET po
176 Get the value at offset C<po> in the current pad
178 =for apidoc m|SV *|PAD_SVl |PADOFFSET po
179 Lightweight and lvalue version of C<PAD_SV>.
180 Get or set the value at offset C<po> in the current pad.
181 Unlike C<PAD_SV>, does not print diagnostics with -DX.
182 For internal use only.
184 =for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po
185 Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
187 =for apidoc m|void|PAD_SET_CUR |PADLIST padlist|I32 n
188 Set the current pad to be pad C<n> in the padlist, saving
189 the previous current pad. NB currently this macro expands to a string too
190 long for some compilers, so it's best to replace it with
193 PAD_SET_CUR_NOSAVE(padlist,n);
196 =for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n
197 like PAD_SET_CUR, but without the save
199 =for apidoc m|void|PAD_SAVE_SETNULLPAD
200 Save the current pad then set it to null.
202 =for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad
203 Save the current pad to the local variable opad, then make the
204 current pad equal to npad
206 =for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad
207 Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL()
213 # define PAD_SV(po) pad_sv(po)
214 # define PAD_SETSV(po,sv) pad_setsv(po,sv)
216 # define PAD_SV(po) (PL_curpad[po])
217 # define PAD_SETSV(po,sv) PL_curpad[po] = (sv)
220 #define PAD_SVl(po) (PL_curpad[po])
222 #define PAD_BASE_SV(padlist, po) \
223 (AvARRAY(padlist)[1]) \
224 ? AvARRAY(MUTABLE_AV((AvARRAY(padlist)[1])))[po] : NULL;
227 #define PAD_SET_CUR_NOSAVE(padlist,nth) \
228 PL_comppad = (PAD*) (AvARRAY(padlist)[nth]); \
229 PL_curpad = AvARRAY(PL_comppad); \
230 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
231 "Pad 0x%"UVxf"[0x%"UVxf"] set_cur depth=%d\n", \
232 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(nth)));
235 #define PAD_SET_CUR(padlist,nth) \
237 PAD_SET_CUR_NOSAVE(padlist,nth);
240 #define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \
241 PL_comppad = NULL; PL_curpad = NULL; \
242 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n"));
244 #define PAD_SAVE_LOCAL(opad,npad) \
246 PL_comppad = (npad); \
247 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
248 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
249 "Pad 0x%"UVxf"[0x%"UVxf"] save_local\n", \
250 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
252 #define PAD_RESTORE_LOCAL(opad) \
253 assert(!opad || !SvIS_FREED(opad)); \
255 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
256 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
257 "Pad 0x%"UVxf"[0x%"UVxf"] restore_local\n", \
258 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
262 =for apidoc m|void|CX_CURPAD_SAVE|struct context
263 Save the current pad in the given context block structure.
265 =for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po
266 Access the SV at offset po in the saved current pad in the given
267 context block structure (can be used as an lvalue).
272 #define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad
273 #define CX_CURPAD_SV(block,po) (AvARRAY(MUTABLE_AV(((block).oldcomppad)))[po])
277 =for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po
278 Return the flags for the current compiling pad name
279 at offset C<po>. Assumes a valid slot entry.
281 =for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po
282 Return the name of the current compiling pad name
283 at offset C<po>. Assumes a valid slot entry.
285 =for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po
286 Return the type (stash) of the current compiling pad name at offset
287 C<po>. Must be a valid name. Returns null if not typed.
289 =for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po
290 Return the stash associated with an C<our> variable.
291 Assumes the slot entry is a valid C<our> lexical.
293 =for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po
294 The generation number of the name at offset C<po> in the current
295 compiling pad (lvalue). Note that C<SvUVX> is hijacked for this purpose.
297 =for apidoc m|STRLEN|PAD_COMPNAME_GEN_set|PADOFFSET po|int gen
298 Sets the generation number of the name at offset C<po> in the current
299 ling pad (lvalue) to C<gen>. Note that C<SvUV_set> is hijacked for this purpose.
305 #define PAD_COMPNAME_SV(po) (*av_fetch(PL_comppad_name, (po), FALSE))
306 #define PAD_COMPNAME_FLAGS(po) SvFLAGS(PAD_COMPNAME_SV(po))
307 #define PAD_COMPNAME_FLAGS_isOUR(po) SvPAD_OUR(PAD_COMPNAME_SV(po))
308 #define PAD_COMPNAME_PV(po) SvPV_nolen(PAD_COMPNAME_SV(po))
310 #define PAD_COMPNAME_TYPE(po) pad_compname_type(po)
312 #define PAD_COMPNAME_OURSTASH(po) \
313 (SvOURSTASH(PAD_COMPNAME_SV(po)))
315 #define PAD_COMPNAME_GEN(po) ((STRLEN)SvUVX(AvARRAY(PL_comppad_name)[po]))
317 #define PAD_COMPNAME_GEN_set(po, gen) SvUV_set(AvARRAY(PL_comppad_name)[po], (UV)(gen))
321 =for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl|CLONE_PARAMS* param
322 Clone the state variables associated with running and compiling pads.
327 /* NB - we set PL_comppad to null unless it points at a value that
328 * has already been dup'ed, ie it points to part of an active padlist.
329 * Otherwise PL_comppad ends up being a leaked scalar in code like
331 * threads->create(sub { threads->create(sub {...} ) } );
332 * where the second thread dups the outer sub's comppad but not the
333 * sub's CV or padlist. */
335 #define PAD_CLONE_VARS(proto_perl, param) \
336 PL_comppad = av_dup(proto_perl->Icomppad, param); \
337 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
338 PL_comppad_name = av_dup(proto_perl->Icomppad_name, param); \
339 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \
340 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \
341 PL_min_intro_pending = proto_perl->Imin_intro_pending; \
342 PL_max_intro_pending = proto_perl->Imax_intro_pending; \
343 PL_padix = proto_perl->Ipadix; \
344 PL_padix_floor = proto_perl->Ipadix_floor; \
345 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \
346 PL_cop_seqmax = proto_perl->Icop_seqmax;
349 =for apidoc Am|PADOFFSET|pad_add_name_pvs|const char *name|U32 flags|HV *typestash|HV *ourstash
351 Exactly like L</pad_add_name_pvn>, but takes a literal string instead
352 of a string/length pair.
357 #define pad_add_name_pvs(name,flags,typestash,ourstash) \
358 Perl_pad_add_name_pvn(aTHX_ STR_WITH_LEN(name), flags, typestash, ourstash)
361 =for apidoc Am|PADOFFSET|pad_findmy_pvs|const char *name|U32 flags
363 Exactly like L</pad_findmy_pvn>, but takes a literal string instead
364 of a string/length pair.
369 #define pad_findmy_pvs(name,flags) \
370 Perl_pad_findmy_pvn(aTHX_ STR_WITH_LEN(name), flags)
374 * c-indentation-style: bsd
376 * indent-tabs-mode: nil
379 * ex: set ts=8 sts=4 sw=4 et: