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Change the documentation of the return values of @INC-hooks to match
[perl5.git] / regexp.h
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a0d0e21e 1/* regexp.h
d6376244 2 *
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3 * Copyright (C) 1993, 1994, 1996, 1997, 1999, 2000, 2001, 2003,
4 * by Larry Wall and others
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5 *
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.
8 *
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9 */
10
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11/*
12 * Definitions etc. for regexp(3) routines.
13 *
14 * Caveat: this is V8 regexp(3) [actually, a reimplementation thereof],
15 * not the System V one.
16 */
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17#ifndef PLUGGABLE_RE_EXTENSION
18/* we don't want to include this stuff if we are inside Nicholas'
19 * pluggable regex engine code */
378cc40b 20
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21struct regnode {
22 U8 flags;
23 U8 type;
24 U16 next_off;
25};
26
27typedef struct regnode regnode;
28
cad2e5aa 29struct reg_substr_data;
2779dcf1 30
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31struct reg_data;
32
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33struct regexp_engine;
34
378cc40b 35typedef struct regexp {
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36 I32 *startp;
37 I32 *endp;
c277df42 38 regnode *regstclass;
2779dcf1 39 struct reg_substr_data *substrs;
cf93c79d 40 char *precomp; /* pre-compilation regular expression */
c277df42 41 struct reg_data *data; /* Additional data. */
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42 char *subbeg; /* saved or original string
43 so \digit works forever. */
f8c7b90f 44#ifdef PERL_OLD_COPY_ON_WRITE
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45 SV *saved_copy; /* If non-NULL, SV which is COW from original */
46#endif
fac92740 47 U32 *offsets; /* offset annotations 20001228 MJD */
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48 I32 sublen; /* Length of string pointed by subbeg */
49 I32 refcnt;
50 I32 minlen; /* mininum possible length of $& */
51 I32 prelen; /* length of precomp */
52 U32 nparens; /* number of parentheses */
53 U32 lastparen; /* last paren matched */
a01268b5 54 U32 lastcloseparen; /* last paren matched */
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55 U32 reganch; /* Internal use only +
56 Tainted information used by regexec? */
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57 HV *paren_names; /* Paren names */
58 const struct regexp_engine* engine;
c277df42 59 regnode program[1]; /* Unwarranted chumminess with compiler. */
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60} regexp;
61
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62
63typedef struct re_scream_pos_data_s
64{
65 char **scream_olds; /* match pos */
66 I32 *scream_pos; /* Internal iterator of scream. */
67} re_scream_pos_data;
68
69typedef struct regexp_engine {
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70 regexp* (*comp) (pTHX_ char* exp, char* xend, PMOP* pm);
71 I32 (*exec) (pTHX_ regexp* prog, char* stringarg, char* strend,
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72 char* strbeg, I32 minend, SV* screamer,
73 void* data, U32 flags);
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74 char* (*intuit) (pTHX_ regexp *prog, SV *sv, char *strpos,
75 char *strend, U32 flags,
76 struct re_scream_pos_data_s *data);
77 SV* (*checkstr) (pTHX_ regexp *prog);
78 void (*free) (pTHX_ struct regexp* r);
79#ifdef USE_ITHREADS
80 regexp* (*dupe) (pTHX_ const regexp *r, CLONE_PARAMS *param);
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81#endif
82} regexp_engine;
83
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84#define ROPT_ANCH (ROPT_ANCH_BOL|ROPT_ANCH_MBOL|ROPT_ANCH_GPOS|ROPT_ANCH_SBOL)
85#define ROPT_ANCH_SINGLE (ROPT_ANCH_SBOL|ROPT_ANCH_GPOS)
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86#define ROPT_ANCH_BOL 0x00000001
87#define ROPT_ANCH_MBOL 0x00000002
88#define ROPT_ANCH_SBOL 0x00000004
89#define ROPT_ANCH_GPOS 0x00000008
90#define ROPT_SKIP 0x00000010
91#define ROPT_IMPLICIT 0x00000020 /* Converted .* to ^.* */
92#define ROPT_NOSCAN 0x00000040 /* Check-string always at start. */
93#define ROPT_GPOS_SEEN 0x00000080
94#define ROPT_CHECK_ALL 0x00000100
95#define ROPT_LOOKBEHIND_SEEN 0x00000200
96#define ROPT_EVAL_SEEN 0x00000400
97#define ROPT_CANY_SEEN 0x00000800
cce850e4 98#define ROPT_SANY_SEEN ROPT_CANY_SEEN /* src bckwrd cmpt */
f9f4320a 99#define ROPT_GPOS_CHECK (ROPT_GPOS_SEEN|ROPT_ANCH_GPOS)
a0ed51b3 100
8782bef2 101/* 0xf800 of reganch is used by PMf_COMPILETIME */
c277df42 102
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103#define ROPT_UTF8 0x00010000
104#define ROPT_NAUGHTY 0x00020000 /* how exponential is this pattern? */
105#define ROPT_COPY_DONE 0x00040000 /* subbeg is a copy of the string */
106#define ROPT_TAINTED_SEEN 0x00080000
a30b2f1f 107#define ROPT_MATCH_UTF8 0x10000000 /* subbeg is utf-8 */
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108#define ROPT_RECURSE_SEEN 0x20000000
109#define ROPT_VERBARG_SEEN 0x40000000
a0ed51b3 110
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111#define RE_USE_INTUIT_NOML 0x00100000 /* Best to intuit before matching */
112#define RE_USE_INTUIT_ML 0x00200000
113#define REINT_AUTORITATIVE_NOML 0x00400000 /* Can trust a positive answer */
be8e71aa 114#define REINT_AUTORITATIVE_ML 0x00800000
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115#define REINT_ONCE_NOML 0x01000000 /* Intuit can succed once only. */
116#define REINT_ONCE_ML 0x02000000
117#define RE_INTUIT_ONECHAR 0x04000000
118#define RE_INTUIT_TAIL 0x08000000
119
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120
121#define RE_USE_INTUIT (RE_USE_INTUIT_NOML|RE_USE_INTUIT_ML)
122#define REINT_AUTORITATIVE (REINT_AUTORITATIVE_NOML|REINT_AUTORITATIVE_ML)
123#define REINT_ONCE (REINT_ONCE_NOML|REINT_ONCE_ML)
124
c277df42 125#define RX_MATCH_TAINTED(prog) ((prog)->reganch & ROPT_TAINTED_SEEN)
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126#define RX_MATCH_TAINTED_on(prog) ((prog)->reganch |= ROPT_TAINTED_SEEN)
127#define RX_MATCH_TAINTED_off(prog) ((prog)->reganch &= ~ROPT_TAINTED_SEEN)
128#define RX_MATCH_TAINTED_set(prog, t) ((t) \
129 ? RX_MATCH_TAINTED_on(prog) \
130 : RX_MATCH_TAINTED_off(prog))
c277df42 131
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132#define RX_MATCH_COPIED(prog) ((prog)->reganch & ROPT_COPY_DONE)
133#define RX_MATCH_COPIED_on(prog) ((prog)->reganch |= ROPT_COPY_DONE)
134#define RX_MATCH_COPIED_off(prog) ((prog)->reganch &= ~ROPT_COPY_DONE)
135#define RX_MATCH_COPIED_set(prog,t) ((t) \
136 ? RX_MATCH_COPIED_on(prog) \
137 : RX_MATCH_COPIED_off(prog))
f9f4320a 138
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139#endif /* PLUGGABLE_RE_EXTENSION */
140
141/* Stuff that needs to be included in the plugable extension goes below here */
142
143#define RE_DEBUG_BIT 0x20000000
144#define RX_DEBUG(prog) ((prog)->reganch & RE_DEBUG_BIT)
145#define RX_DEBUG_on(prog) ((prog)->reganch |= RE_DEBUG_BIT)
cf93c79d 146
f8c7b90f 147#ifdef PERL_OLD_COPY_ON_WRITE
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148#define RX_MATCH_COPY_FREE(rx) \
149 STMT_START {if (rx->saved_copy) { \
150 SV_CHECK_THINKFIRST_COW_DROP(rx->saved_copy); \
151 } \
152 if (RX_MATCH_COPIED(rx)) { \
153 Safefree(rx->subbeg); \
154 RX_MATCH_COPIED_off(rx); \
155 }} STMT_END
156#else
157#define RX_MATCH_COPY_FREE(rx) \
158 STMT_START {if (RX_MATCH_COPIED(rx)) { \
159 Safefree(rx->subbeg); \
160 RX_MATCH_COPIED_off(rx); \
161 }} STMT_END
162#endif
163
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164#define RX_MATCH_UTF8(prog) ((prog)->reganch & ROPT_MATCH_UTF8)
165#define RX_MATCH_UTF8_on(prog) ((prog)->reganch |= ROPT_MATCH_UTF8)
166#define RX_MATCH_UTF8_off(prog) ((prog)->reganch &= ~ROPT_MATCH_UTF8)
167#define RX_MATCH_UTF8_set(prog, t) ((t) \
168 ? (RX_MATCH_UTF8_on(prog), (PL_reg_match_utf8 = 1)) \
169 : (RX_MATCH_UTF8_off(prog), (PL_reg_match_utf8 = 0)))
170
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171#define REXEC_COPY_STR 0x01 /* Need to copy the string. */
172#define REXEC_CHECKED 0x02 /* check_substr already checked. */
173#define REXEC_SCREAM 0x04 /* use scream table. */
174#define REXEC_IGNOREPOS 0x08 /* \G matches at start. */
cf93c79d 175#define REXEC_NOT_FIRST 0x10 /* This is another iteration of //g. */
c277df42 176
155aba94 177#define ReREFCNT_inc(re) ((void)(re && re->refcnt++), re)
f9f4320a 178#define ReREFCNT_dec(re) CALLREGFREE(re)
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179
180#define FBMcf_TAIL_DOLLAR 1
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181#define FBMcf_TAIL_DOLLARM 2
182#define FBMcf_TAIL_Z 4
183#define FBMcf_TAIL_z 8
184#define FBMcf_TAIL (FBMcf_TAIL_DOLLAR|FBMcf_TAIL_DOLLARM|FBMcf_TAIL_Z|FBMcf_TAIL_z)
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185
186#define FBMrf_MULTILINE 1
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187
188struct re_scream_pos_data_s;
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189
190/* an accepting state/position*/
191struct _reg_trie_accepted {
192 U8 *endpos;
193 U16 wordnum;
194};
195typedef struct _reg_trie_accepted reg_trie_accepted;
196
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197/* some basic information about the current match that is created by
198 * Perl_regexec_flags and then passed to regtry(), regmatch() etc */
199
200typedef struct {
201 regexp *prog;
202 char *bol;
203 char *till;
204 SV *sv;
205 char *ganch;
24b23f37 206 char *cutpoint;
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207} regmatch_info;
208
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209
210/* structures for holding and saving the state maintained by regmatch() */
211
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212#define MAX_RECURSE_EVAL_NOCHANGE_DEPTH 50
213
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214typedef I32 CHECKPOINT;
215
a0374537 216typedef struct regmatch_state {
40a82448 217 int resume_state; /* where to jump to on return */
24d3c4a9 218 char *locinput; /* where to backtrack in string on failure */
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219
220 union {
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221
222 /* this is a fake union member that matches the first element
223 * of each member that needs to store positive backtrack
224 * information */
225 struct {
226 struct regmatch_state *prev_yes_state;
227 } yes;
228
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229 struct {
230 reg_trie_accepted *accept_buff;
166ba7cd 231 U32 accepted; /* how many accepting states we have seen */
7f69552c 232 U16 *jump; /* positive offsets from me */
166ba7cd 233 regnode *B; /* node following the trie */
7f69552c 234 regnode *me; /* Which node am I - needed for jump tries*/
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235 } trie;
236
237 struct {
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238 /* this first element must match u.yes */
239 struct regmatch_state *prev_yes_state;
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240 struct regmatch_state *prev_eval;
241 struct regmatch_state *prev_curlyx;
aa283a38 242 regexp *prev_rex;
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243 U32 toggle_reg_flags; /* what bits in PL_reg_flags to
244 flip when transitioning between
245 inner and outer rexen */
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246 CHECKPOINT cp; /* remember current savestack indexes */
247 CHECKPOINT lastcp;
40a82448 248 regnode *B; /* the node following us */
6bda09f9 249 U32 close_paren; /* which close bracket is our end */
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250 } eval;
251
252 struct {
c476f425 253 /* this first element must match u.yes */
262b90c4 254 struct regmatch_state *prev_yes_state;
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255 struct regmatch_state *prev_curlyx; /* previous cur_curlyx */
256 CHECKPOINT cp; /* remember current savestack index */
257 bool minmod;
a0374537 258 int parenfloor;/* how far back to strip paren data */
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259 int min; /* the minimal number of A's to match */
260 int max; /* the maximal number of A's to match */
261 regnode *A, *B; /* the nodes corresponding to /A*B/ */
262
263 /* these two are modified by WHILEM */
264 int count; /* how many instances of A we've matched */
265 char *lastloc;/* where previous A matched (0-len detect) */
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266 } curlyx;
267
268 struct {
c476f425 269 /* this first element must match u.yes */
262b90c4 270 struct regmatch_state *prev_yes_state;
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271 struct regmatch_state *save_curlyx;
272 CHECKPOINT cp; /* remember current savestack indexes */
273 CHECKPOINT lastcp;
274 char *save_lastloc; /* previous curlyx.lastloc */
275 I32 cache_offset;
276 I32 cache_mask;
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277 } whilem;
278
279 struct {
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280 I32 lastparen;
281 regnode *next_branch; /* next branch node */
282 CHECKPOINT cp;
283 } branch;
284
285 struct {
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286 /* this first element must match u.yes */
287 struct regmatch_state *prev_yes_state;
e822a8b4 288 I32 c1, c2; /* case fold search */
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289 CHECKPOINT cp;
290 I32 alen; /* length of first-matched A string */
291 I32 count;
0cadcf80 292 bool minmod;
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293 regnode *A, *B; /* the nodes corresponding to /A*B/ */
294 regnode *me; /* the curlym node */
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295 } curlym;
296
297 struct {
298 I32 paren;
c255a977 299 CHECKPOINT cp;
e822a8b4 300 I32 c1, c2; /* case fold search */
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301 char *maxpos; /* highest possible point in string to match */
302 char *oldloc; /* the previous locinput */
e822a8b4 303 int count;
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304 int min, max; /* {m,n} */
305 regnode *A, *B; /* the nodes corresponding to /A*B/ */
306 } curly; /* and CURLYN/PLUS/STAR */
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307
308 struct {
309 /* this first element must match u.yes */
310 struct regmatch_state *prev_yes_state;
311 I32 wanted;
24d3c4a9 312 I32 logical; /* saved copy of 'logical' var */
40a82448 313 regnode *me; /* the IFMATCH/SUSPEND/UNLESSM node */
dad79028 314 } ifmatch; /* and SUSPEND/UNLESSM */
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315
316 struct {
317 /* this first element must match u.yes */
318 struct regmatch_state *prev_yes_state;
319 struct regmatch_state *prev_mark;
320 SV* mark_name;
321 char *mark_loc;
322 } mark;
d8319b27 323 } u;
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324} regmatch_state;
325
326/* how many regmatch_state structs to allocate as a single slab.
327 * We do it in 4K blocks for efficiency. The "3" is 2 for the next/prev
328 * pointers, plus 1 for any mythical malloc overhead. */
329
330#define PERL_REGMATCH_SLAB_SLOTS \
331 ((4096 - 3 * sizeof (void*)) / sizeof(regmatch_state))
332
333typedef struct regmatch_slab {
334 regmatch_state states[PERL_REGMATCH_SLAB_SLOTS];
335 struct regmatch_slab *prev, *next;
336} regmatch_slab;
1ade1aa1 337
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338#define PL_reg_flags PL_reg_state.re_state_reg_flags
339#define PL_bostr PL_reg_state.re_state_bostr
340#define PL_reginput PL_reg_state.re_state_reginput
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341#define PL_regeol PL_reg_state.re_state_regeol
342#define PL_regstartp PL_reg_state.re_state_regstartp
343#define PL_regendp PL_reg_state.re_state_regendp
344#define PL_reglastparen PL_reg_state.re_state_reglastparen
345#define PL_reglastcloseparen PL_reg_state.re_state_reglastcloseparen
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346#define PL_reg_start_tmp PL_reg_state.re_state_reg_start_tmp
347#define PL_reg_start_tmpl PL_reg_state.re_state_reg_start_tmpl
348#define PL_reg_eval_set PL_reg_state.re_state_reg_eval_set
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349#define PL_reg_match_utf8 PL_reg_state.re_state_reg_match_utf8
350#define PL_reg_magic PL_reg_state.re_state_reg_magic
351#define PL_reg_oldpos PL_reg_state.re_state_reg_oldpos
352#define PL_reg_oldcurpm PL_reg_state.re_state_reg_oldcurpm
353#define PL_reg_curpm PL_reg_state.re_state_reg_curpm
354#define PL_reg_oldsaved PL_reg_state.re_state_reg_oldsaved
355#define PL_reg_oldsavedlen PL_reg_state.re_state_reg_oldsavedlen
356#define PL_reg_maxiter PL_reg_state.re_state_reg_maxiter
357#define PL_reg_leftiter PL_reg_state.re_state_reg_leftiter
358#define PL_reg_poscache PL_reg_state.re_state_reg_poscache
359#define PL_reg_poscache_size PL_reg_state.re_state_reg_poscache_size
360#define PL_regsize PL_reg_state.re_state_regsize
361#define PL_reg_starttry PL_reg_state.re_state_reg_starttry
362#define PL_nrs PL_reg_state.re_state_nrs
363
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364struct re_save_state {
365 U32 re_state_reg_flags; /* from regexec.c */
366 char *re_state_bostr;
367 char *re_state_reginput; /* String-input pointer. */
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368 char *re_state_regeol; /* End of input, for $ check. */
369 I32 *re_state_regstartp; /* Pointer to startp array. */
370 I32 *re_state_regendp; /* Ditto for endp. */
371 U32 *re_state_reglastparen; /* Similarly for lastparen. */
372 U32 *re_state_reglastcloseparen; /* Similarly for lastcloseparen. */
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373 char **re_state_reg_start_tmp; /* from regexec.c */
374 U32 re_state_reg_start_tmpl; /* from regexec.c */
375 I32 re_state_reg_eval_set; /* from regexec.c */
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376 bool re_state_reg_match_utf8; /* from regexec.c */
377 MAGIC *re_state_reg_magic; /* from regexec.c */
378 I32 re_state_reg_oldpos; /* from regexec.c */
379 PMOP *re_state_reg_oldcurpm; /* from regexec.c */
380 PMOP *re_state_reg_curpm; /* from regexec.c */
381 char *re_state_reg_oldsaved; /* old saved substr during match */
382 STRLEN re_state_reg_oldsavedlen; /* old length of saved substr during match */
383 I32 re_state_reg_maxiter; /* max wait until caching pos */
384 I32 re_state_reg_leftiter; /* wait until caching pos */
385 char *re_state_reg_poscache; /* cache of pos of WHILEM */
386 STRLEN re_state_reg_poscache_size; /* size of pos cache of WHILEM */
387 I32 re_state_regsize; /* from regexec.c */
388 char *re_state_reg_starttry; /* from regexec.c */
389#ifdef PERL_OLD_COPY_ON_WRITE
46ab3289 390 SV *re_state_nrs; /* was placeholder: unused since 5.8.0 (5.7.2 patch #12027 for bug ID 20010815.012). Used to save rx->saved_copy */
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391#endif
392};
393
394#define SAVESTACK_ALLOC_FOR_RE_SAVE_STATE \
395 (1 + ((sizeof(struct re_save_state) - 1) / sizeof(*PL_savestack)))
396/*
397 * Local variables:
398 * c-indentation-style: bsd
399 * c-basic-offset: 4
400 * indent-tabs-mode: t
401 * End:
402 *
403 * ex: set ts=8 sts=4 sw=4 noet:
404 */