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Change PAD_MAX to something a bit less FORTRAN-ish than 999999999.
[perl5.git] / pad.h
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1/* pad.h
2 *
45ca242c 3 * Copyright (C) 2002, 2003, 2005, by Larry Wall and others
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4 *
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
7 *
8 * This file defines the types and macros associated with the API for
9 * manipulating scratchpads, which are used by perl to store lexical
10 * variables, op targets and constants.
11 */
12
13
14
15
16/* a padlist is currently just an AV; but that might change,
17 * so hide the type. Ditto a pad. */
18
19typedef AV PADLIST;
f3548bdc 20typedef AV PAD;
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21
22
23/* offsets within a pad */
24
25#if PTRSIZE == 4
26typedef U32TYPE PADOFFSET;
27#else
28# if PTRSIZE == 8
29typedef U64TYPE PADOFFSET;
30# endif
31#endif
32#define NOT_IN_PAD ((PADOFFSET) -1)
33
34
35/* flags for the pad_new() function */
36
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37#define padnew_CLONE 1 /* this pad is for a cloned CV */
38#define padnew_SAVE 2 /* save old globals */
39#define padnew_SAVESUB 4 /* also save extra stuff for start of sub */
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40
41/* values for the pad_tidy() function */
42
43typedef enum {
44 padtidy_SUB, /* tidy up a pad for a sub, */
45 padtidy_SUBCLONE, /* a cloned sub, */
46 padtidy_FORMAT /* or a format */
47} padtidy_type;
48
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49/* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine
50 * whether PL_comppad and PL_curpad are consistent and whether they have
51 * active values */
dd2155a4 52
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53#ifndef PERL_MAD
54# define pad_peg(label)
55#endif
56
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57#ifdef DEBUGGING
58# define ASSERT_CURPAD_LEGAL(label) \
1dba731d 59 pad_peg(label); \
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60 if (PL_comppad ? (AvARRAY(PL_comppad) != PL_curpad) : (PL_curpad != 0)) \
61 Perl_croak(aTHX_ "panic: illegal pad in %s: 0x%"UVxf"[0x%"UVxf"]",\
62 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
63
64
65# define ASSERT_CURPAD_ACTIVE(label) \
1dba731d 66 pad_peg(label); \
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67 if (!PL_comppad || (AvARRAY(PL_comppad) != PL_curpad)) \
68 Perl_croak(aTHX_ "panic: invalid pad in %s: 0x%"UVxf"[0x%"UVxf"]",\
69 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
70#else
71# define ASSERT_CURPAD_LEGAL(label)
72# define ASSERT_CURPAD_ACTIVE(label)
73#endif
74
75
76
77/* Note: the following three macros are actually defined in scope.h, but
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78 * they are documented here for completeness, since they directly or
79 * indirectly affect pads.
80
81=for apidoc m|void|SAVEPADSV |PADOFFSET po
82Save a pad slot (used to restore after an iteration)
83
f3548bdc 84XXX DAPM it would make more sense to make the arg a PADOFFSET
dd2155a4 85=for apidoc m|void|SAVECLEARSV |SV **svp
eeb8d49e 86Clear the pointed to pad value on scope exit. (i.e. the runtime action of 'my')
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87
88=for apidoc m|void|SAVECOMPPAD
89save PL_comppad and PL_curpad
90
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91
92
93
94
95=for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv
96Set the slot at offset C<po> in the current pad to C<sv>
97
98=for apidoc m|void|PAD_SV |PADOFFSET po
99Get the value at offset C<po> in the current pad
100
101=for apidoc m|SV *|PAD_SVl |PADOFFSET po
102Lightweight and lvalue version of C<PAD_SV>.
103Get or set the value at offset C<po> in the current pad.
104Unlike C<PAD_SV>, does not print diagnostics with -DX.
105For internal use only.
106
107=for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po
108Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
109
110=for apidoc m|void|PAD_SET_CUR |PADLIST padlist|I32 n
111Set the current pad to be pad C<n> in the padlist, saving
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112the previous current pad. NB currently this macro expands to a string too
113long for some compilers, so it's best to replace it with
114
115 SAVECOMPPAD();
116 PAD_SET_CUR_NOSAVE(padlist,n);
117
dd2155a4 118
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119=for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n
120like PAD_SET_CUR, but without the save
121
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122=for apidoc m|void|PAD_SAVE_SETNULLPAD
123Save the current pad then set it to null.
124
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125=for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad
126Save the current pad to the local variable opad, then make the
127current pad equal to npad
128
129=for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad
130Restore the old pad saved into the local variable opad by PAD_SAVE_LOCAL()
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131
132=cut
133*/
134
135#ifdef DEBUGGING
136# define PAD_SV(po) pad_sv(po)
137# define PAD_SETSV(po,sv) pad_setsv(po,sv)
138#else
139# define PAD_SV(po) (PL_curpad[po])
140# define PAD_SETSV(po,sv) PL_curpad[po] = (sv)
141#endif
142
143#define PAD_SVl(po) (PL_curpad[po])
144
145#define PAD_BASE_SV(padlist, po) \
146 (AvARRAY(padlist)[1]) \
a0714e2c 147 ? AvARRAY((AV*)(AvARRAY(padlist)[1]))[po] : NULL;
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148
149
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150#define PAD_SET_CUR_NOSAVE(padlist,nth) \
151 PL_comppad = (PAD*) (AvARRAY(padlist)[nth]); \
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152 PL_curpad = AvARRAY(PL_comppad); \
153 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
154 "Pad 0x%"UVxf"[0x%"UVxf"] set_cur depth=%d\n", \
de5e01c2 155 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(nth)));
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156
157
de5e01c2 158#define PAD_SET_CUR(padlist,nth) \
4e380990 159 SAVECOMPPAD(); \
de5e01c2 160 PAD_SET_CUR_NOSAVE(padlist,nth);
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161
162
f3548bdc 163#define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \
4608196e 164 PL_comppad = NULL; PL_curpad = NULL; \
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165 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n"));
166
167#define PAD_SAVE_LOCAL(opad,npad) \
168 opad = PL_comppad; \
169 PL_comppad = (npad); \
4608196e 170 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
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171 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
172 "Pad 0x%"UVxf"[0x%"UVxf"] save_local\n", \
173 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
174
175#define PAD_RESTORE_LOCAL(opad) \
176 PL_comppad = opad; \
4608196e 177 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
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178 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
179 "Pad 0x%"UVxf"[0x%"UVxf"] restore_local\n", \
180 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
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181
182
183/*
184=for apidoc m|void|CX_CURPAD_SAVE|struct context
185Save the current pad in the given context block structure.
186
f3548bdc 187=for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po
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188Access the SV at offset po in the saved current pad in the given
189context block structure (can be used as an lvalue).
190
191=cut
192*/
193
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194#define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad
195#define CX_CURPAD_SV(block,po) (AvARRAY((AV*)((block).oldcomppad))[po])
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196
197
198/*
199=for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po
200Return the flags for the current compiling pad name
201at offset C<po>. Assumes a valid slot entry.
202
203=for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po
204Return the name of the current compiling pad name
205at offset C<po>. Assumes a valid slot entry.
206
207=for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po
208Return the type (stash) of the current compiling pad name at offset
209C<po>. Must be a valid name. Returns null if not typed.
210
211=for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po
212Return the stash associated with an C<our> variable.
213Assumes the slot entry is a valid C<our> lexical.
214
215=for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po
216The generation number of the name at offset C<po> in the current
217compiling pad (lvalue). Note that C<SvCUR> is hijacked for this purpose.
218
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219=for apidoc m|STRLEN|PAD_COMPNAME_GEN_set|PADOFFSET po|int gen
220Sets the generation number of the name at offset C<po> in the current
221ling pad (lvalue) to C<gen>. Note that C<SvCUR_set> is hijacked for this purpose.
222
dd2155a4 223=cut
b162af07 224
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225*/
226
227#define PAD_COMPNAME_FLAGS(po) SvFLAGS(*av_fetch(PL_comppad_name, (po), FALSE))
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228#define PAD_COMPNAME_FLAGS_isOUR(po) \
229 ((PAD_COMPNAME_FLAGS(po) & (SVpad_NAME|SVpad_OUR)) == (SVpad_NAME|SVpad_OUR))
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230#define PAD_COMPNAME_PV(po) SvPV_nolen(*av_fetch(PL_comppad_name, (po), FALSE))
231
b21dc031 232#define PAD_COMPNAME_TYPE(po) pad_compname_type(po)
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233
234#define PAD_COMPNAME_OURSTASH(po) \
035dab74 235 (OURSTASH(*av_fetch(PL_comppad_name, (po), FALSE)))
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236
237#define PAD_COMPNAME_GEN(po) SvCUR(AvARRAY(PL_comppad_name)[po])
238
b162af07 239#define PAD_COMPNAME_GEN_set(po, gen) SvCUR_set(AvARRAY(PL_comppad_name)[po], gen)
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240
241
242/*
243=for apidoc m|void|PAD_DUP|PADLIST dstpad|PADLIST srcpad|CLONE_PARAMS* param
244Clone a padlist.
245
246=for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl \
247|CLONE_PARAMS* param
248Clone the state variables associated with running and compiling pads.
249
250=cut
251*/
252
253
254#define PAD_DUP(dstpad, srcpad, param) \
255 if ((srcpad) && !AvREAL(srcpad)) { \
256 /* XXX padlists are real, but pretend to be not */ \
257 AvREAL_on(srcpad); \
258 (dstpad) = av_dup_inc((srcpad), param); \
259 AvREAL_off(srcpad); \
260 AvREAL_off(dstpad); \
261 } \
262 else \
263 (dstpad) = av_dup_inc((srcpad), param);
264
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265/* NB - we set PL_comppad to null unless it points at a value that
266 * has already been dup'ed, ie it points to part of an active padlist.
267 * Otherwise PL_comppad ends up being a leaked scalar in code like
268 * the following:
269 * threads->create(sub { threads->create(sub {...} ) } );
270 * where the second thread dups the outer sub's comppad but not the
271 * sub's CV or padlist. */
f3548bdc 272
dd2155a4 273#define PAD_CLONE_VARS(proto_perl, param) \
8f77bfdb 274 PL_comppad = (AV *) ptr_table_fetch(PL_ptr_table, proto_perl->Icomppad); \
4608196e 275 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
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276 PL_comppad_name = av_dup(proto_perl->Icomppad_name, param); \
277 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \
278 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \
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279 PL_min_intro_pending = proto_perl->Imin_intro_pending; \
280 PL_max_intro_pending = proto_perl->Imax_intro_pending; \
281 PL_padix = proto_perl->Ipadix; \
282 PL_padix_floor = proto_perl->Ipadix_floor; \
283 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \
284 PL_cop_seqmax = proto_perl->Icop_seqmax;