xref: /openbsd-src/gnu/usr.bin/perl/regexp.h (revision 7bbe964f6b7d22ad07ca46292495604f942eba4e)
1 /*    regexp.h
2  *
3  *    Copyright (C) 1993, 1994, 1996, 1997, 1999, 2000, 2001, 2003,
4  *    2005, 2006, 2007, 2008 by Larry Wall and others
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  *
9  */
10 
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  */
17 #ifndef PLUGGABLE_RE_EXTENSION
18 /* we don't want to include this stuff if we are inside of
19    an external regex engine based on the core one - like re 'debug'*/
20 
21 struct regnode {
22     U8	flags;
23     U8  type;
24     U16 next_off;
25 };
26 
27 typedef struct regnode regnode;
28 
29 struct reg_substr_data;
30 
31 struct reg_data;
32 
33 struct regexp_engine;
34 struct regexp;
35 
36 struct reg_substr_datum {
37     I32 min_offset;
38     I32 max_offset;
39     SV *substr;		/* non-utf8 variant */
40     SV *utf8_substr;	/* utf8 variant */
41     I32 end_shift;
42 };
43 struct reg_substr_data {
44     struct reg_substr_datum data[3];	/* Actual array */
45 };
46 
47 #ifdef PERL_OLD_COPY_ON_WRITE
48 #define SV_SAVED_COPY   SV *saved_copy; /* If non-NULL, SV which is COW from original */
49 #else
50 #define SV_SAVED_COPY
51 #endif
52 
53 typedef struct regexp_paren_pair {
54     I32 start;
55     I32 end;
56 } regexp_paren_pair;
57 
58 /*
59   The regexp/REGEXP struct, see L<perlreapi> for further documentation
60   on the individual fields. The struct is ordered so that the most
61   commonly used fields are placed at the start.
62 
63   Any patch that adds items to this struct will need to include
64   changes to F<sv.c> (C<Perl_re_dup()>) and F<regcomp.c>
65   (C<pregfree()>). This involves freeing or cloning items in the
66   regexp's data array based on the data item's type.
67 */
68 
69 typedef struct regexp {
70         /* what engine created this regexp? */
71 	const struct regexp_engine* engine;
72 	struct regexp* mother_re; /* what re is this a lightweight copy of? */
73 
74 	/* Information about the match that the perl core uses to manage things */
75 	U32 extflags;           /* Flags used both externally and internally */
76 	I32 minlen;		/* mininum possible length of string to match */
77 	I32 minlenret;		/* mininum possible length of $& */
78 	U32 gofs;               /* chars left of pos that we search from */
79 	struct reg_substr_data *substrs; /* substring data about strings that must appear
80                                    in the final match, used for optimisations */
81 	U32 nparens;		/* number of capture buffers */
82 
83         /* private engine specific data */
84 	U32 intflags;		/* Engine Specific Internal flags */
85 	void *pprivate;         /* Data private to the regex engine which
86                                    created this object. */
87 
88         /* Data about the last/current match. These are modified during matching*/
89         U32 lastparen;		/* last open paren matched */
90 	U32 lastcloseparen;	/* last close paren matched */
91         regexp_paren_pair *swap;  /* Swap copy of *offs */
92         regexp_paren_pair *offs;  /* Array of offsets for (@-) and (@+) */
93 
94 	char *subbeg;		/* saved or original string
95 				   so \digit works forever. */
96 	SV_SAVED_COPY           /* If non-NULL, SV which is COW from original */
97 	I32 sublen;		/* Length of string pointed by subbeg */
98 
99 
100         /* Information about the match that isn't often used */
101 	I32 prelen;		/* length of precomp */
102 	const char *precomp;	/* pre-compilation regular expression */
103 	/* wrapped can't be const char*, as it is returned by sv_2pv_flags */
104 	char *wrapped;          /* wrapped version of the pattern */
105 	I32 wraplen;		/* length of wrapped */
106 	I32 seen_evals;         /* number of eval groups in the pattern - for security checks */
107         HV *paren_names;	/* Optional hash of paren names */
108 
109         /* Refcount of this regexp */
110 	I32 refcnt;             /* Refcount of this regexp */
111 } regexp;
112 
113 #define RXp_PAREN_NAMES(rx)	((rx)->paren_names)
114 
115 /* used for high speed searches */
116 typedef struct re_scream_pos_data_s
117 {
118     char **scream_olds;		/* match pos */
119     I32 *scream_pos;		/* Internal iterator of scream. */
120 } re_scream_pos_data;
121 
122 /* regexp_engine structure. This is the dispatch table for regexes.
123  * Any regex engine implementation must be able to build one of these.
124  */
125 typedef struct regexp_engine {
126     REGEXP* (*comp) (pTHX_ const SV * const pattern, const U32 flags);
127     I32     (*exec) (pTHX_ REGEXP * const rx, char* stringarg, char* strend,
128                      char* strbeg, I32 minend, SV* screamer,
129                      void* data, U32 flags);
130     char*   (*intuit) (pTHX_ REGEXP * const rx, SV *sv, char *strpos,
131                        char *strend, const U32 flags,
132                        re_scream_pos_data *data);
133     SV*     (*checkstr) (pTHX_ REGEXP * const rx);
134     void    (*free) (pTHX_ REGEXP * const rx);
135     void    (*numbered_buff_FETCH) (pTHX_ REGEXP * const rx, const I32 paren,
136                                     SV * const sv);
137     void    (*numbered_buff_STORE) (pTHX_ REGEXP * const rx, const I32 paren,
138                                    SV const * const value);
139     I32     (*numbered_buff_LENGTH) (pTHX_ REGEXP * const rx, const SV * const sv,
140                                     const I32 paren);
141     SV*     (*named_buff) (pTHX_ REGEXP * const rx, SV * const key,
142                            SV * const value, const U32 flags);
143     SV*     (*named_buff_iter) (pTHX_ REGEXP * const rx, const SV * const lastkey,
144                                 const U32 flags);
145     SV*     (*qr_package)(pTHX_ REGEXP * const rx);
146 #ifdef USE_ITHREADS
147     void*   (*dupe) (pTHX_ REGEXP * const rx, CLONE_PARAMS *param);
148 #endif
149 } regexp_engine;
150 
151 /*
152   These are passed to the numbered capture variable callbacks as the
153   paren name. >= 1 is reserved for actual numbered captures, i.e. $1,
154   $2 etc.
155 */
156 #define RX_BUFF_IDX_PREMATCH  -2 /* $` / ${^PREMATCH}  */
157 #define RX_BUFF_IDX_POSTMATCH -1 /* $' / ${^POSTMATCH} */
158 #define RX_BUFF_IDX_FULLMATCH      0 /* $& / ${^MATCH}     */
159 
160 /*
161   Flags that are passed to the named_buff and named_buff_iter
162   callbacks above. Those routines are called from universal.c via the
163   Tie::Hash::NamedCapture interface for %+ and %- and the re::
164   functions in the same file.
165 */
166 
167 /* The Tie::Hash::NamedCapture operation this is part of, if any */
168 #define RXapif_FETCH     0x0001
169 #define RXapif_STORE     0x0002
170 #define RXapif_DELETE    0x0004
171 #define RXapif_CLEAR     0x0008
172 #define RXapif_EXISTS    0x0010
173 #define RXapif_SCALAR    0x0020
174 #define RXapif_FIRSTKEY  0x0040
175 #define RXapif_NEXTKEY   0x0080
176 
177 /* Whether %+ or %- is being operated on */
178 #define RXapif_ONE       0x0100 /* %+ */
179 #define RXapif_ALL       0x0200 /* %- */
180 
181 /* Whether this is being called from a re:: function */
182 #define RXapif_REGNAME         0x0400
183 #define RXapif_REGNAMES        0x0800
184 #define RXapif_REGNAMES_COUNT  0x1000
185 
186 /*
187 =head1 REGEXP Functions
188 
189 =for apidoc Am|REGEXP *|SvRX|SV *sv
190 
191 Convenience macro to get the REGEXP from a SV. This is approximately
192 equivalent to the following snippet:
193 
194     if (SvMAGICAL(sv))
195         mg_get(sv);
196     if (SvROK(sv) &&
197         (tmpsv = (SV*)SvRV(sv)) &&
198         SvTYPE(tmpsv) == SVt_PVMG &&
199         (tmpmg = mg_find(tmpsv, PERL_MAGIC_qr)))
200     {
201         return (REGEXP *)tmpmg->mg_obj;
202     }
203 
204 NULL will be returned if a REGEXP* is not found.
205 
206 =for apidoc Am|bool|SvRXOK|SV* sv
207 
208 Returns a boolean indicating whether the SV contains qr magic
209 (PERL_MAGIC_qr).
210 
211 If you want to do something with the REGEXP* later use SvRX instead
212 and check for NULL.
213 
214 =cut
215 */
216 
217 #define SvRX(sv)   (Perl_get_re_arg(aTHX_ sv))
218 #define SvRXOK(sv) (Perl_get_re_arg(aTHX_ sv) ? TRUE : FALSE)
219 
220 
221 /* Flags stored in regexp->extflags
222  * These are used by code external to the regexp engine
223  *
224  * Note that flags starting with RXf_PMf_ have exact equivalents
225  * stored in op_pmflags and which are defined in op.h, they are defined
226  * numerically here only for clarity.
227  *
228  * NOTE: if you modify any RXf flags you should run regen.pl or regcomp.pl
229  * so that regnodes.h is updated with the changes.
230  *
231  */
232 
233 /* Anchor and GPOS related stuff */
234 #define RXf_ANCH_BOL    	0x00000001
235 #define RXf_ANCH_MBOL   	0x00000002
236 #define RXf_ANCH_SBOL   	0x00000004
237 #define RXf_ANCH_GPOS   	0x00000008
238 #define RXf_GPOS_SEEN   	0x00000010
239 #define RXf_GPOS_FLOAT  	0x00000020
240 /* two bits here */
241 #define RXf_ANCH        	(RXf_ANCH_BOL|RXf_ANCH_MBOL|RXf_ANCH_GPOS|RXf_ANCH_SBOL)
242 #define RXf_GPOS_CHECK          (RXf_GPOS_SEEN|RXf_ANCH_GPOS)
243 #define RXf_ANCH_SINGLE         (RXf_ANCH_SBOL|RXf_ANCH_GPOS)
244 
245 /* Flags indicating special patterns */
246 #define RXf_SKIPWHITE		0x00000100 /* Pattern is for a split / / */
247 #define RXf_START_ONLY		0x00000200 /* Pattern is /^/ */
248 #define RXf_WHITE		0x00000400 /* Pattern is /\s+/ */
249 #define RXf_NULL		0x40000000 /* Pattern is // */
250 
251 /* 0x1F800 of extflags is used by (RXf_)PMf_COMPILETIME
252  * If you change these you need to change the equivalent flags in op.h, and
253  * vice versa.  */
254 #define RXf_PMf_LOCALE  	0x00000800 /* use locale */
255 #define RXf_PMf_MULTILINE	0x00001000 /* /m         */
256 #define RXf_PMf_SINGLELINE	0x00002000 /* /s         */
257 #define RXf_PMf_FOLD    	0x00004000 /* /i         */
258 #define RXf_PMf_EXTENDED	0x00008000 /* /x         */
259 #define RXf_PMf_KEEPCOPY	0x00010000 /* /p         */
260 /* these flags are transfered from the PMOP->op_pmflags member during compilation */
261 #define RXf_PMf_STD_PMMOD_SHIFT	12
262 #define RXf_PMf_STD_PMMOD	(RXf_PMf_MULTILINE|RXf_PMf_SINGLELINE|RXf_PMf_FOLD|RXf_PMf_EXTENDED)
263 #define RXf_PMf_COMPILETIME	(RXf_PMf_MULTILINE|RXf_PMf_SINGLELINE|RXf_PMf_LOCALE|RXf_PMf_FOLD|RXf_PMf_EXTENDED|RXf_PMf_KEEPCOPY)
264 
265 #define CASE_STD_PMMOD_FLAGS_PARSE_SET(pmfl)                        \
266     case IGNORE_PAT_MOD:    *(pmfl) |= RXf_PMf_FOLD;       break;   \
267     case MULTILINE_PAT_MOD: *(pmfl) |= RXf_PMf_MULTILINE;  break;   \
268     case SINGLE_PAT_MOD:    *(pmfl) |= RXf_PMf_SINGLELINE; break;   \
269     case XTENDED_PAT_MOD:   *(pmfl) |= RXf_PMf_EXTENDED;   break
270 
271 /* chars and strings used as regex pattern modifiers
272  * Singlular is a 'c'har, plural is a "string"
273  *
274  * NOTE, KEEPCOPY was originally 'k', but was changed to 'p' for preserve
275  * for compatibility reasons with Regexp::Common which highjacked (?k:...)
276  * for its own uses. So 'k' is out as well.
277  */
278 #define EXEC_PAT_MOD         'e'
279 #define KEEPCOPY_PAT_MOD     'p'
280 #define ONCE_PAT_MOD         'o'
281 #define GLOBAL_PAT_MOD       'g'
282 #define CONTINUE_PAT_MOD     'c'
283 #define MULTILINE_PAT_MOD    'm'
284 #define SINGLE_PAT_MOD       's'
285 #define IGNORE_PAT_MOD       'i'
286 #define XTENDED_PAT_MOD      'x'
287 
288 #define ONCE_PAT_MODS        "o"
289 #define KEEPCOPY_PAT_MODS    "p"
290 #define EXEC_PAT_MODS        "e"
291 #define LOOP_PAT_MODS        "gc"
292 
293 #define STD_PAT_MODS        "msix"
294 
295 #define INT_PAT_MODS    STD_PAT_MODS    KEEPCOPY_PAT_MODS
296 
297 #define EXT_PAT_MODS    ONCE_PAT_MODS   KEEPCOPY_PAT_MODS
298 #define QR_PAT_MODS     STD_PAT_MODS    EXT_PAT_MODS
299 #define M_PAT_MODS      QR_PAT_MODS     LOOP_PAT_MODS
300 #define S_PAT_MODS      M_PAT_MODS      EXEC_PAT_MODS
301 
302 /*
303  * NOTE: if you modify any RXf flags you should run regen.pl or regcomp.pl
304  * so that regnodes.h is updated with the changes.
305  *
306  */
307 
308 /* What we have seen */
309 #define RXf_LOOKBEHIND_SEEN	0x00020000
310 #define RXf_EVAL_SEEN   	0x00040000
311 #define RXf_CANY_SEEN   	0x00080000
312 
313 /* Special */
314 #define RXf_NOSCAN      	0x00100000
315 #define RXf_CHECK_ALL   	0x00200000
316 
317 /* UTF8 related */
318 #define RXf_UTF8        	0x00400000
319 #define RXf_MATCH_UTF8  	0x00800000
320 
321 /* Intuit related */
322 #define RXf_USE_INTUIT_NOML	0x01000000
323 #define RXf_USE_INTUIT_ML	0x02000000
324 #define RXf_INTUIT_TAIL 	0x04000000
325 
326 /*
327   Set in Perl_pmruntime if op_flags & OPf_SPECIAL, i.e. split. Will
328   be used by regex engines to check whether they should set
329   RXf_SKIPWHITE
330 */
331 #define RXf_SPLIT           0x08000000
332 
333 #define RXf_USE_INTUIT		(RXf_USE_INTUIT_NOML|RXf_USE_INTUIT_ML)
334 
335 /* Copy and tainted info */
336 #define RXf_COPY_DONE   	0x10000000
337 #define RXf_TAINTED_SEEN	0x20000000
338 #define RXf_TAINTED             0x80000000 /* this pattern is tainted */
339 
340 /*
341  * NOTE: if you modify any RXf flags you should run regen.pl or regcomp.pl
342  * so that regnodes.h is updated with the changes.
343  *
344  */
345 
346 #define RX_HAS_CUTGROUP(prog) ((prog)->intflags & PREGf_CUTGROUP_SEEN)
347 #define RXp_MATCH_TAINTED(prog)	(RXp_EXTFLAGS(prog) & RXf_TAINTED_SEEN)
348 #define RX_MATCH_TAINTED(prog)	(RX_EXTFLAGS(prog) & RXf_TAINTED_SEEN)
349 #define RX_MATCH_TAINTED_on(prog) (RX_EXTFLAGS(prog) |= RXf_TAINTED_SEEN)
350 #define RX_MATCH_TAINTED_off(prog) (RX_EXTFLAGS(prog) &= ~RXf_TAINTED_SEEN)
351 #define RX_MATCH_TAINTED_set(prog, t) ((t) \
352 				       ? RX_MATCH_TAINTED_on(prog) \
353 				       : RX_MATCH_TAINTED_off(prog))
354 
355 #define RXp_MATCH_COPIED(prog)		(RXp_EXTFLAGS(prog) & RXf_COPY_DONE)
356 #define RX_MATCH_COPIED(prog)		(RX_EXTFLAGS(prog) & RXf_COPY_DONE)
357 #define RXp_MATCH_COPIED_on(prog)	(RXp_EXTFLAGS(prog) |= RXf_COPY_DONE)
358 #define RX_MATCH_COPIED_on(prog)	(RX_EXTFLAGS(prog) |= RXf_COPY_DONE)
359 #define RXp_MATCH_COPIED_off(prog)	(RXp_EXTFLAGS(prog) &= ~RXf_COPY_DONE)
360 #define RX_MATCH_COPIED_off(prog)	(RX_EXTFLAGS(prog) &= ~RXf_COPY_DONE)
361 #define RX_MATCH_COPIED_set(prog,t)	((t) \
362 					 ? RX_MATCH_COPIED_on(prog) \
363 					 : RX_MATCH_COPIED_off(prog))
364 
365 #define RXp_EXTFLAGS(rx)	((rx)->extflags)
366 
367 #define RX_PRECOMP(prog)	((prog)->precomp)
368 /* *** 5.10.x-specific definition of RX_PRECOMP_const */
369 #define RX_PRECOMP_const(prog)	((prog)->precomp)
370 #define RX_PRELEN(prog)		((prog)->prelen)
371 #define RX_WRAPPED(prog)	((prog)->wrapped)
372 #define RX_WRAPLEN(prog)	((prog)->wraplen)
373 #define RX_CHECK_SUBSTR(prog)	((prog)->check_substr)
374 #define RX_EXTFLAGS(prog)	((prog)->extflags)
375 #define RX_REFCNT(prog)		((prog)->refcnt)
376 #define RX_ENGINE(prog)		((prog)->engine)
377 #define RX_SUBBEG(prog)		((prog)->subbeg)
378 #define RX_OFFS(prog)		((prog)->offs)
379 #define RX_NPARENS(prog)	((prog)->nparens)
380 #define RX_SUBLEN(prog)		((prog)->sublen)
381 #define RX_SUBBEG(prog)		((prog)->subbeg)
382 #define RX_MINLEN(prog)		((prog)->minlen)
383 #define RX_MINLENRET(prog)	((prog)->minlenret)
384 #define RX_GOFS(prog)		((prog)->gofs)
385 #define RX_LASTPAREN(prog)	((prog)->lastparen)
386 #define RX_LASTCLOSEPAREN(prog)	((prog)->lastcloseparen)
387 #define RX_SEEN_EVALS(prog)	((prog)->seen_evals)
388 
389 #endif /* PLUGGABLE_RE_EXTENSION */
390 
391 /* Stuff that needs to be included in the plugable extension goes below here */
392 
393 #ifdef PERL_OLD_COPY_ON_WRITE
394 #define RX_MATCH_COPY_FREE(rx) \
395 	STMT_START {if (rx->saved_copy) { \
396 	    SV_CHECK_THINKFIRST_COW_DROP(rx->saved_copy); \
397 	} \
398 	if (RX_MATCH_COPIED(rx)) { \
399 	    Safefree(RX_SUBBEG(rx)); \
400 	    RX_MATCH_COPIED_off(rx); \
401 	}} STMT_END
402 #else
403 #define RX_MATCH_COPY_FREE(rx) \
404 	STMT_START {if (RX_MATCH_COPIED(rx)) { \
405 	    Safefree(RX_SUBBEG(rx)); \
406 	    RX_MATCH_COPIED_off(rx); \
407 	}} STMT_END
408 #endif
409 
410 #define RXp_MATCH_UTF8(prog)		(RXp_EXTFLAGS(prog) & RXf_MATCH_UTF8)
411 #define RX_MATCH_UTF8(prog)		(RX_EXTFLAGS(prog) & RXf_MATCH_UTF8)
412 #define RX_MATCH_UTF8_on(prog)		(RX_EXTFLAGS(prog) |= RXf_MATCH_UTF8)
413 #define RX_MATCH_UTF8_off(prog)		(RX_EXTFLAGS(prog) &= ~RXf_MATCH_UTF8)
414 #define RX_MATCH_UTF8_set(prog, t)	((t) \
415 			? (RX_MATCH_UTF8_on(prog), (PL_reg_match_utf8 = 1)) \
416 			: (RX_MATCH_UTF8_off(prog), (PL_reg_match_utf8 = 0)))
417 
418 /* Whether the pattern stored at RX_WRAPPED is in UTF-8  */
419 #define RX_UTF8(prog)			(RX_EXTFLAGS(prog) & RXf_UTF8)
420 
421 #define REXEC_COPY_STR	0x01		/* Need to copy the string. */
422 #define REXEC_CHECKED	0x02		/* check_substr already checked. */
423 #define REXEC_SCREAM	0x04		/* use scream table. */
424 #define REXEC_IGNOREPOS	0x08		/* \G matches at start. */
425 #define REXEC_NOT_FIRST	0x10		/* This is another iteration of //g. */
426 
427 #define ReREFCNT_inc(re) ((void)(re && re->refcnt++), re)
428 #define ReREFCNT_dec(re) CALLREGFREE(re)
429 
430 #define FBMcf_TAIL_DOLLAR	1
431 #define FBMcf_TAIL_DOLLARM	2
432 #define FBMcf_TAIL_Z		4
433 #define FBMcf_TAIL_z		8
434 #define FBMcf_TAIL		(FBMcf_TAIL_DOLLAR|FBMcf_TAIL_DOLLARM|FBMcf_TAIL_Z|FBMcf_TAIL_z)
435 
436 #define FBMrf_MULTILINE	1
437 
438 /* an accepting state/position*/
439 struct _reg_trie_accepted {
440     U8   *endpos;
441     U16  wordnum;
442 };
443 typedef struct _reg_trie_accepted reg_trie_accepted;
444 
445 /* some basic information about the current match that is created by
446  * Perl_regexec_flags and then passed to regtry(), regmatch() etc */
447 
448 typedef struct {
449     regexp *prog;
450     char *bol;
451     char *till;
452     SV *sv;
453     char *ganch;
454     char *cutpoint;
455 } regmatch_info;
456 
457 
458 /* structures for holding and saving the state maintained by regmatch() */
459 
460 #ifndef MAX_RECURSE_EVAL_NOCHANGE_DEPTH
461 #define MAX_RECURSE_EVAL_NOCHANGE_DEPTH 1000
462 #endif
463 
464 typedef I32 CHECKPOINT;
465 
466 typedef struct regmatch_state {
467     int resume_state;		/* where to jump to on return */
468     char *locinput;		/* where to backtrack in string on failure */
469 
470     union {
471 
472 	/* this is a fake union member that matches the first element
473 	 * of each member that needs to store positive backtrack
474 	 * information */
475 	struct {
476 	    struct regmatch_state *prev_yes_state;
477 	} yes;
478 
479         /* branchlike members */
480         /* this is a fake union member that matches the first elements
481          * of each member that needs to behave like a branch */
482         struct {
483 	    /* this first element must match u.yes */
484 	    struct regmatch_state *prev_yes_state;
485 	    U32 lastparen;
486 	    CHECKPOINT cp;
487 
488         } branchlike;
489 
490 	struct {
491 	    /* the first elements must match u.branchlike */
492 	    struct regmatch_state *prev_yes_state;
493 	    U32 lastparen;
494 	    CHECKPOINT cp;
495 
496 	    regnode *next_branch; /* next branch node */
497 	} branch;
498 
499 	struct {
500 	    /* the first elements must match u.branchlike */
501 	    struct regmatch_state *prev_yes_state;
502 	    U32 lastparen;
503 	    CHECKPOINT cp;
504 
505 	    reg_trie_accepted *accept_buff; /* accepting states we have seen */
506 	    U32		accepted; /* how many accepting states we have seen */
507 	    U16         *jump;  /* positive offsets from me */
508 	    regnode	*B;	/* node following the trie */
509 	    regnode	*me;	/* Which node am I - needed for jump tries*/
510 	} trie;
511 
512         /* special types - these members are used to store state for special
513            regops like eval, if/then, lookaround and the markpoint state */
514 	struct {
515 	    /* this first element must match u.yes */
516 	    struct regmatch_state *prev_yes_state;
517 	    struct regmatch_state *prev_eval;
518 	    struct regmatch_state *prev_curlyx;
519 	    regexp	*prev_rex;
520 	    U32		toggle_reg_flags; /* what bits in PL_reg_flags to
521 					    flip when transitioning between
522 					    inner and outer rexen */
523 	    CHECKPOINT	cp;	/* remember current savestack indexes */
524 	    CHECKPOINT	lastcp;
525 	    U32        close_paren; /* which close bracket is our end */
526 	    regnode	*B;	/* the node following us  */
527 	} eval;
528 
529 	struct {
530 	    /* this first element must match u.yes */
531 	    struct regmatch_state *prev_yes_state;
532 	    I32 wanted;
533 	    I32 logical;	/* saved copy of 'logical' var */
534 	    regnode  *me; /* the IFMATCH/SUSPEND/UNLESSM node  */
535 	} ifmatch; /* and SUSPEND/UNLESSM */
536 
537 	struct {
538 	    /* this first element must match u.yes */
539 	    struct regmatch_state *prev_yes_state;
540 	    struct regmatch_state *prev_mark;
541 	    SV* mark_name;
542 	    char *mark_loc;
543 	} mark;
544 
545 	struct {
546 	    int val;
547 	} keeper;
548 
549         /* quantifiers - these members are used for storing state for
550            for the regops used to implement quantifiers */
551 	struct {
552 	    /* this first element must match u.yes */
553 	    struct regmatch_state *prev_yes_state;
554 	    struct regmatch_state *prev_curlyx; /* previous cur_curlyx */
555 	    regnode	*A, *B;	/* the nodes corresponding to /A*B/  */
556 	    CHECKPOINT	cp;	/* remember current savestack index */
557 	    bool	minmod;
558 	    int		parenfloor;/* how far back to strip paren data */
559 	    int		min;	/* the minimal number of A's to match */
560 	    int		max;	/* the maximal number of A's to match */
561 
562 	    /* these two are modified by WHILEM */
563 	    int		count;	/* how many instances of A we've matched */
564 	    char	*lastloc;/* where previous A matched (0-len detect) */
565 	} curlyx;
566 
567 	struct {
568 	    /* this first element must match u.yes */
569 	    struct regmatch_state *prev_yes_state;
570 	    struct regmatch_state *save_curlyx;
571 	    CHECKPOINT	cp;	/* remember current savestack indexes */
572 	    CHECKPOINT	lastcp;
573 	    char	*save_lastloc;	/* previous curlyx.lastloc */
574 	    I32		cache_offset;
575 	    I32		cache_mask;
576 	} whilem;
577 
578 	struct {
579 	    /* this first element must match u.yes */
580 	    struct regmatch_state *prev_yes_state;
581 	    I32 c1, c2;		/* case fold search */
582 	    CHECKPOINT cp;
583 	    I32 alen;		/* length of first-matched A string */
584 	    I32 count;
585 	    bool minmod;
586 	    regnode *A, *B;	/* the nodes corresponding to /A*B/  */
587 	    regnode *me;	/* the curlym node */
588 	} curlym;
589 
590 	struct {
591 	    U32 paren;
592 	    CHECKPOINT cp;
593 	    I32 c1, c2;		/* case fold search */
594 	    char *maxpos;	/* highest possible point in string to match */
595 	    char *oldloc;	/* the previous locinput */
596 	    int count;
597 	    int min, max;	/* {m,n} */
598 	    regnode *A, *B;	/* the nodes corresponding to /A*B/  */
599 	} curly; /* and CURLYN/PLUS/STAR */
600 
601     } u;
602 } regmatch_state;
603 
604 /* how many regmatch_state structs to allocate as a single slab.
605  * We do it in 4K blocks for efficiency. The "3" is 2 for the next/prev
606  * pointers, plus 1 for any mythical malloc overhead. */
607 
608 #define PERL_REGMATCH_SLAB_SLOTS \
609     ((4096 - 3 * sizeof (void*)) / sizeof(regmatch_state))
610 
611 typedef struct regmatch_slab {
612     regmatch_state states[PERL_REGMATCH_SLAB_SLOTS];
613     struct regmatch_slab *prev, *next;
614 } regmatch_slab;
615 
616 #define PL_reg_flags		PL_reg_state.re_state_reg_flags
617 #define PL_bostr		PL_reg_state.re_state_bostr
618 #define PL_reginput		PL_reg_state.re_state_reginput
619 #define PL_regeol		PL_reg_state.re_state_regeol
620 #define PL_regoffs		PL_reg_state.re_state_regoffs
621 #define PL_reglastparen		PL_reg_state.re_state_reglastparen
622 #define PL_reglastcloseparen	PL_reg_state.re_state_reglastcloseparen
623 #define PL_reg_start_tmp	PL_reg_state.re_state_reg_start_tmp
624 #define PL_reg_start_tmpl	PL_reg_state.re_state_reg_start_tmpl
625 #define PL_reg_eval_set		PL_reg_state.re_state_reg_eval_set
626 #define PL_reg_match_utf8	PL_reg_state.re_state_reg_match_utf8
627 #define PL_reg_magic		PL_reg_state.re_state_reg_magic
628 #define PL_reg_oldpos		PL_reg_state.re_state_reg_oldpos
629 #define PL_reg_oldcurpm		PL_reg_state.re_state_reg_oldcurpm
630 #define PL_reg_curpm		PL_reg_state.re_state_reg_curpm
631 #define PL_reg_oldsaved		PL_reg_state.re_state_reg_oldsaved
632 #define PL_reg_oldsavedlen	PL_reg_state.re_state_reg_oldsavedlen
633 #define PL_reg_maxiter		PL_reg_state.re_state_reg_maxiter
634 #define PL_reg_leftiter		PL_reg_state.re_state_reg_leftiter
635 #define PL_reg_poscache		PL_reg_state.re_state_reg_poscache
636 #define PL_reg_poscache_size	PL_reg_state.re_state_reg_poscache_size
637 #define PL_regsize		PL_reg_state.re_state_regsize
638 #define PL_reg_starttry		PL_reg_state.re_state_reg_starttry
639 #define PL_nrs			PL_reg_state.re_state_nrs
640 
641 struct re_save_state {
642     U32 re_state_reg_flags;		/* from regexec.c */
643     U32 re_state_reg_start_tmpl;	/* from regexec.c */
644     I32 re_state_reg_eval_set;		/* from regexec.c */
645     bool re_state_reg_match_utf8;	/* from regexec.c */
646     char *re_state_bostr;
647     char *re_state_reginput;		/* String-input pointer. */
648     char *re_state_regeol;		/* End of input, for $ check. */
649     regexp_paren_pair *re_state_regoffs;  /* Pointer to start/end pairs */
650     U32 *re_state_reglastparen;		/* Similarly for lastparen. */
651     U32 *re_state_reglastcloseparen;	/* Similarly for lastcloseparen. */
652     char **re_state_reg_start_tmp;	/* from regexec.c */
653     MAGIC *re_state_reg_magic;		/* from regexec.c */
654     PMOP *re_state_reg_oldcurpm;	/* from regexec.c */
655     PMOP *re_state_reg_curpm;		/* from regexec.c */
656     char *re_state_reg_oldsaved;	/* old saved substr during match */
657     STRLEN re_state_reg_oldsavedlen;	/* old length of saved substr during match */
658     STRLEN re_state_reg_poscache_size;	/* size of pos cache of WHILEM */
659     I32 re_state_reg_oldpos;		/* from regexec.c */
660     I32 re_state_reg_maxiter;		/* max wait until caching pos */
661     I32 re_state_reg_leftiter;		/* wait until caching pos */
662     U32 re_state_regsize;		/* from regexec.c */
663     char *re_state_reg_poscache;	/* cache of pos of WHILEM */
664     char *re_state_reg_starttry;	/* from regexec.c */
665 #ifdef PERL_OLD_COPY_ON_WRITE
666     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 */
667 #endif
668 };
669 
670 #define SAVESTACK_ALLOC_FOR_RE_SAVE_STATE \
671 	(1 + ((sizeof(struct re_save_state) - 1) / sizeof(*PL_savestack)))
672 
673 /*
674  * Local variables:
675  * c-indentation-style: bsd
676  * c-basic-offset: 4
677  * indent-tabs-mode: t
678  * End:
679  *
680  * ex: set ts=8 sts=4 sw=4 noet:
681  */
682