1/*
2 * re_*comp and friends - compile REs
3 * This file #includes several others (see the bottom).
4 *
5 * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved.
6 *
7 * Development of this software was funded, in part, by Cray Research Inc.,
8 * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
9 * Corporation, none of whom are responsible for the results. The author
10 * thanks all of them.
11 *
12 * Redistribution and use in source and binary forms -- with or without
13 * modification -- are permitted for any purpose, provided that
14 * redistributions in source form retain this entire copyright notice and
15 * indicate the origin and nature of any modifications.
16 *
17 * I'd appreciate being given credit for this package in the documentation
18 * of software which uses it, but that is not a requirement.
19 *
20 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
21 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
22 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23 * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 * src/backend/regex/regcomp.c
32 *
33 */
34
35#include "regex/regguts.h"
36
37/*
38 * forward declarations, up here so forward datatypes etc. are defined early
39 */
40/* === regcomp.c === */
41static void moresubs(struct vars *, int);
42static int freev(struct vars *, int);
43static void makesearch(struct vars *, struct nfa *);
44static struct subre *parse(struct vars *, int, int, struct state *, struct state *);
45static struct subre *parsebranch(struct vars *, int, int, struct state *, struct state *, int);
46static void parseqatom(struct vars *, int, int, struct state *, struct state *, struct subre *);
47static void nonword(struct vars *, int, struct state *, struct state *);
48static void word(struct vars *, int, struct state *, struct state *);
49static int scannum(struct vars *);
50static void repeat(struct vars *, struct state *, struct state *, int, int);
51static void bracket(struct vars *, struct state *, struct state *);
52static void cbracket(struct vars *, struct state *, struct state *);
53static void brackpart(struct vars *, struct state *, struct state *);
54static const chr *scanplain(struct vars *);
55static void onechr(struct vars *, chr, struct state *, struct state *);
56static void wordchrs(struct vars *);
57static void processlacon(struct vars *, struct state *, struct state *, int,
58 struct state *, struct state *);
59static struct subre *subre(struct vars *, int, int, struct state *, struct state *);
60static void freesubre(struct vars *, struct subre *);
61static void freesrnode(struct vars *, struct subre *);
62static void optst(struct vars *, struct subre *);
63static int numst(struct subre *, int);
64static void markst(struct subre *);
65static void cleanst(struct vars *);
66static long nfatree(struct vars *, struct subre *, FILE *);
67static long nfanode(struct vars *, struct subre *, int, FILE *);
68static int newlacon(struct vars *, struct state *, struct state *, int);
69static void freelacons(struct subre *, int);
70static void rfree(regex_t *);
71static int rcancelrequested(void);
72static int rstacktoodeep(void);
73
74#ifdef REG_DEBUG
75static void dump(regex_t *, FILE *);
76static void dumpst(struct subre *, FILE *, int);
77static void stdump(struct subre *, FILE *, int);
78static const char *stid(struct subre *, char *, size_t);
79#endif
80/* === regc_lex.c === */
81static void lexstart(struct vars *);
82static void prefixes(struct vars *);
83static void lexnest(struct vars *, const chr *, const chr *);
84static void lexword(struct vars *);
85static int (struct vars *);
86static int lexescape(struct vars *);
87static chr lexdigits(struct vars *, int, int, int);
88static int brenext(struct vars *, chr);
89static void (struct vars *);
90static chr newline(void);
91static chr chrnamed(struct vars *, const chr *, const chr *, chr);
92
93/* === regc_color.c === */
94static void initcm(struct vars *, struct colormap *);
95static void freecm(struct colormap *);
96static color maxcolor(struct colormap *);
97static color newcolor(struct colormap *);
98static void freecolor(struct colormap *, color);
99static color pseudocolor(struct colormap *);
100static color subcolor(struct colormap *, chr);
101static color subcolorhi(struct colormap *, color *);
102static color newsub(struct colormap *, color);
103static int newhicolorrow(struct colormap *, int);
104static void newhicolorcols(struct colormap *);
105static void subcolorcvec(struct vars *, struct cvec *, struct state *, struct state *);
106static void subcoloronechr(struct vars *, chr, struct state *, struct state *, color *);
107static void subcoloronerange(struct vars *, chr, chr, struct state *, struct state *, color *);
108static void subcoloronerow(struct vars *, int, struct state *, struct state *, color *);
109static void okcolors(struct nfa *, struct colormap *);
110static void colorchain(struct colormap *, struct arc *);
111static void uncolorchain(struct colormap *, struct arc *);
112static void rainbow(struct nfa *, struct colormap *, int, color, struct state *, struct state *);
113static void colorcomplement(struct nfa *, struct colormap *, int, struct state *, struct state *, struct state *);
114
115#ifdef REG_DEBUG
116static void dumpcolors(struct colormap *, FILE *);
117static void dumpchr(chr, FILE *);
118#endif
119/* === regc_nfa.c === */
120static struct nfa *newnfa(struct vars *, struct colormap *, struct nfa *);
121static void freenfa(struct nfa *);
122static struct state *newstate(struct nfa *);
123static struct state *newfstate(struct nfa *, int flag);
124static void dropstate(struct nfa *, struct state *);
125static void freestate(struct nfa *, struct state *);
126static void destroystate(struct nfa *, struct state *);
127static void newarc(struct nfa *, int, color, struct state *, struct state *);
128static void createarc(struct nfa *, int, color, struct state *, struct state *);
129static struct arc *allocarc(struct nfa *, struct state *);
130static void freearc(struct nfa *, struct arc *);
131static void changearctarget(struct arc *, struct state *);
132static int hasnonemptyout(struct state *);
133static struct arc *findarc(struct state *, int, color);
134static void cparc(struct nfa *, struct arc *, struct state *, struct state *);
135static void sortins(struct nfa *, struct state *);
136static int sortins_cmp(const void *, const void *);
137static void sortouts(struct nfa *, struct state *);
138static int sortouts_cmp(const void *, const void *);
139static void moveins(struct nfa *, struct state *, struct state *);
140static void copyins(struct nfa *, struct state *, struct state *);
141static void mergeins(struct nfa *, struct state *, struct arc **, int);
142static void moveouts(struct nfa *, struct state *, struct state *);
143static void copyouts(struct nfa *, struct state *, struct state *);
144static void cloneouts(struct nfa *, struct state *, struct state *, struct state *, int);
145static void delsub(struct nfa *, struct state *, struct state *);
146static void deltraverse(struct nfa *, struct state *, struct state *);
147static void dupnfa(struct nfa *, struct state *, struct state *, struct state *, struct state *);
148static void duptraverse(struct nfa *, struct state *, struct state *);
149static void cleartraverse(struct nfa *, struct state *);
150static struct state *single_color_transition(struct state *, struct state *);
151static void specialcolors(struct nfa *);
152static long optimize(struct nfa *, FILE *);
153static void pullback(struct nfa *, FILE *);
154static int pull(struct nfa *, struct arc *, struct state **);
155static void pushfwd(struct nfa *, FILE *);
156static int push(struct nfa *, struct arc *, struct state **);
157
158#define INCOMPATIBLE 1 /* destroys arc */
159#define SATISFIED 2 /* constraint satisfied */
160#define COMPATIBLE 3 /* compatible but not satisfied yet */
161static int combine(struct arc *, struct arc *);
162static void fixempties(struct nfa *, FILE *);
163static struct state *emptyreachable(struct nfa *, struct state *,
164 struct state *, struct arc **);
165static int isconstraintarc(struct arc *);
166static int hasconstraintout(struct state *);
167static void fixconstraintloops(struct nfa *, FILE *);
168static int findconstraintloop(struct nfa *, struct state *);
169static void breakconstraintloop(struct nfa *, struct state *);
170static void clonesuccessorstates(struct nfa *, struct state *, struct state *,
171 struct state *, struct arc *,
172 char *, char *, int);
173static void cleanup(struct nfa *);
174static void markreachable(struct nfa *, struct state *, struct state *, struct state *);
175static void markcanreach(struct nfa *, struct state *, struct state *, struct state *);
176static long analyze(struct nfa *);
177static void compact(struct nfa *, struct cnfa *);
178static void carcsort(struct carc *, size_t);
179static int carc_cmp(const void *, const void *);
180static void freecnfa(struct cnfa *);
181static void dumpnfa(struct nfa *, FILE *);
182
183#ifdef REG_DEBUG
184static void dumpstate(struct state *, FILE *);
185static void dumparcs(struct state *, FILE *);
186static void dumparc(struct arc *, struct state *, FILE *);
187static void dumpcnfa(struct cnfa *, FILE *);
188static void dumpcstate(int, struct cnfa *, FILE *);
189#endif
190/* === regc_cvec.c === */
191static struct cvec *newcvec(int, int);
192static struct cvec *clearcvec(struct cvec *);
193static void addchr(struct cvec *, chr);
194static void addrange(struct cvec *, chr, chr);
195static struct cvec *getcvec(struct vars *, int, int);
196static void freecvec(struct cvec *);
197
198/* === regc_pg_locale.c === */
199static int pg_wc_isdigit(pg_wchar c);
200static int pg_wc_isalpha(pg_wchar c);
201static int pg_wc_isalnum(pg_wchar c);
202static int pg_wc_isupper(pg_wchar c);
203static int pg_wc_islower(pg_wchar c);
204static int pg_wc_isgraph(pg_wchar c);
205static int pg_wc_isprint(pg_wchar c);
206static int pg_wc_ispunct(pg_wchar c);
207static int pg_wc_isspace(pg_wchar c);
208static pg_wchar pg_wc_toupper(pg_wchar c);
209static pg_wchar pg_wc_tolower(pg_wchar c);
210
211/* === regc_locale.c === */
212static chr element(struct vars *, const chr *, const chr *);
213static struct cvec *range(struct vars *, chr, chr, int);
214static int before(chr, chr);
215static struct cvec *eclass(struct vars *, chr, int);
216static struct cvec *cclass(struct vars *, const chr *, const chr *, int);
217static int cclass_column_index(struct colormap *, chr);
218static struct cvec *allcases(struct vars *, chr);
219static int cmp(const chr *, const chr *, size_t);
220static int casecmp(const chr *, const chr *, size_t);
221
222
223/* internal variables, bundled for easy passing around */
224struct vars
225{
226 regex_t *re;
227 const chr *now; /* scan pointer into string */
228 const chr *stop; /* end of string */
229 const chr *savenow; /* saved now and stop for "subroutine call" */
230 const chr *savestop;
231 int err; /* error code (0 if none) */
232 int cflags; /* copy of compile flags */
233 int lasttype; /* type of previous token */
234 int nexttype; /* type of next token */
235 chr nextvalue; /* value (if any) of next token */
236 int lexcon; /* lexical context type (see lex.c) */
237 int nsubexp; /* subexpression count */
238 struct subre **subs; /* subRE pointer vector */
239 size_t nsubs; /* length of vector */
240 struct subre *sub10[10]; /* initial vector, enough for most */
241 struct nfa *nfa; /* the NFA */
242 struct colormap *cm; /* character color map */
243 color nlcolor; /* color of newline */
244 struct state *wordchrs; /* state in nfa holding word-char outarcs */
245 struct subre *tree; /* subexpression tree */
246 struct subre *treechain; /* all tree nodes allocated */
247 struct subre *treefree; /* any free tree nodes */
248 int ntree; /* number of tree nodes, plus one */
249 struct cvec *cv; /* interface cvec */
250 struct cvec *cv2; /* utility cvec */
251 struct subre *lacons; /* lookaround-constraint vector */
252 int nlacons; /* size of lacons[]; note that only slots
253 * numbered 1 .. nlacons-1 are used */
254 size_t spaceused; /* approx. space used for compilation */
255};
256
257/* parsing macros; most know that `v' is the struct vars pointer */
258#define NEXT() (next(v)) /* advance by one token */
259#define SEE(t) (v->nexttype == (t)) /* is next token this? */
260#define EAT(t) (SEE(t) && next(v)) /* if next is this, swallow it */
261#define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
262#define ISERR() VISERR(v)
263#define VERR(vv,e) ((vv)->nexttype = EOS, \
264 (vv)->err = ((vv)->err ? (vv)->err : (e)))
265#define ERR(e) VERR(v, e) /* record an error */
266#define NOERR() {if (ISERR()) return;} /* if error seen, return */
267#define NOERRN() {if (ISERR()) return NULL;} /* NOERR with retval */
268#define NOERRZ() {if (ISERR()) return 0;} /* NOERR with retval */
269#define INSIST(c, e) do { if (!(c)) ERR(e); } while (0) /* error if c false */
270#define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */
271#define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y)
272
273/* token type codes, some also used as NFA arc types */
274#define EMPTY 'n' /* no token present */
275#define EOS 'e' /* end of string */
276#define PLAIN 'p' /* ordinary character */
277#define DIGIT 'd' /* digit (in bound) */
278#define BACKREF 'b' /* back reference */
279#define COLLEL 'I' /* start of [. */
280#define ECLASS 'E' /* start of [= */
281#define CCLASS 'C' /* start of [: */
282#define END 'X' /* end of [. [= [: */
283#define RANGE 'R' /* - within [] which might be range delim. */
284#define LACON 'L' /* lookaround constraint subRE */
285#define AHEAD 'a' /* color-lookahead arc */
286#define BEHIND 'r' /* color-lookbehind arc */
287#define WBDRY 'w' /* word boundary constraint */
288#define NWBDRY 'W' /* non-word-boundary constraint */
289#define SBEGIN 'A' /* beginning of string (even if not BOL) */
290#define SEND 'Z' /* end of string (even if not EOL) */
291#define PREFER 'P' /* length preference */
292
293/* is an arc colored, and hence on a color chain? */
294#define COLORED(a) \
295 ((a)->type == PLAIN || (a)->type == AHEAD || (a)->type == BEHIND)
296
297
298/* static function list */
299static const struct fns functions = {
300 rfree, /* regfree insides */
301 rcancelrequested, /* check for cancel request */
302 rstacktoodeep /* check for stack getting dangerously deep */
303};
304
305
306
307/*
308 * pg_regcomp - compile regular expression
309 *
310 * Note: on failure, no resources remain allocated, so pg_regfree()
311 * need not be applied to re.
312 */
313int
314pg_regcomp(regex_t *re,
315 const chr *string,
316 size_t len,
317 int flags,
318 Oid collation)
319{
320 struct vars var;
321 struct vars *v = &var;
322 struct guts *g;
323 int i;
324 size_t j;
325
326#ifdef REG_DEBUG
327 FILE *debug = (flags & REG_PROGRESS) ? stdout : (FILE *) NULL;
328#else
329 FILE *debug = (FILE *) NULL;
330#endif
331
332#define CNOERR() { if (ISERR()) return freev(v, v->err); }
333
334 /* sanity checks */
335
336 if (re == NULL || string == NULL)
337 return REG_INVARG;
338 if ((flags & REG_QUOTE) &&
339 (flags & (REG_ADVANCED | REG_EXPANDED | REG_NEWLINE)))
340 return REG_INVARG;
341 if (!(flags & REG_EXTENDED) && (flags & REG_ADVF))
342 return REG_INVARG;
343
344 /* Initialize locale-dependent support */
345 pg_set_regex_collation(collation);
346
347 /* initial setup (after which freev() is callable) */
348 v->re = re;
349 v->now = string;
350 v->stop = v->now + len;
351 v->savenow = v->savestop = NULL;
352 v->err = 0;
353 v->cflags = flags;
354 v->nsubexp = 0;
355 v->subs = v->sub10;
356 v->nsubs = 10;
357 for (j = 0; j < v->nsubs; j++)
358 v->subs[j] = NULL;
359 v->nfa = NULL;
360 v->cm = NULL;
361 v->nlcolor = COLORLESS;
362 v->wordchrs = NULL;
363 v->tree = NULL;
364 v->treechain = NULL;
365 v->treefree = NULL;
366 v->cv = NULL;
367 v->cv2 = NULL;
368 v->lacons = NULL;
369 v->nlacons = 0;
370 v->spaceused = 0;
371 re->re_magic = REMAGIC;
372 re->re_info = 0; /* bits get set during parse */
373 re->re_csize = sizeof(chr);
374 re->re_collation = collation;
375 re->re_guts = NULL;
376 re->re_fns = VS(&functions);
377
378 /* more complex setup, malloced things */
379 re->re_guts = VS(MALLOC(sizeof(struct guts)));
380 if (re->re_guts == NULL)
381 return freev(v, REG_ESPACE);
382 g = (struct guts *) re->re_guts;
383 g->tree = NULL;
384 initcm(v, &g->cmap);
385 v->cm = &g->cmap;
386 g->lacons = NULL;
387 g->nlacons = 0;
388 ZAPCNFA(g->search);
389 v->nfa = newnfa(v, v->cm, (struct nfa *) NULL);
390 CNOERR();
391 /* set up a reasonably-sized transient cvec for getcvec usage */
392 v->cv = newcvec(100, 20);
393 if (v->cv == NULL)
394 return freev(v, REG_ESPACE);
395
396 /* parsing */
397 lexstart(v); /* also handles prefixes */
398 if ((v->cflags & REG_NLSTOP) || (v->cflags & REG_NLANCH))
399 {
400 /* assign newline a unique color */
401 v->nlcolor = subcolor(v->cm, newline());
402 okcolors(v->nfa, v->cm);
403 }
404 CNOERR();
405 v->tree = parse(v, EOS, PLAIN, v->nfa->init, v->nfa->final);
406 assert(SEE(EOS)); /* even if error; ISERR() => SEE(EOS) */
407 CNOERR();
408 assert(v->tree != NULL);
409
410 /* finish setup of nfa and its subre tree */
411 specialcolors(v->nfa);
412 CNOERR();
413#ifdef REG_DEBUG
414 if (debug != NULL)
415 {
416 fprintf(debug, "\n\n\n========= RAW ==========\n");
417 dumpnfa(v->nfa, debug);
418 dumpst(v->tree, debug, 1);
419 }
420#endif
421 optst(v, v->tree);
422 v->ntree = numst(v->tree, 1);
423 markst(v->tree);
424 cleanst(v);
425#ifdef REG_DEBUG
426 if (debug != NULL)
427 {
428 fprintf(debug, "\n\n\n========= TREE FIXED ==========\n");
429 dumpst(v->tree, debug, 1);
430 }
431#endif
432
433 /* build compacted NFAs for tree and lacons */
434 re->re_info |= nfatree(v, v->tree, debug);
435 CNOERR();
436 assert(v->nlacons == 0 || v->lacons != NULL);
437 for (i = 1; i < v->nlacons; i++)
438 {
439 struct subre *lasub = &v->lacons[i];
440
441#ifdef REG_DEBUG
442 if (debug != NULL)
443 fprintf(debug, "\n\n\n========= LA%d ==========\n", i);
444#endif
445
446 /* Prepend .* to pattern if it's a lookbehind LACON */
447 nfanode(v, lasub, !LATYPE_IS_AHEAD(lasub->subno), debug);
448 }
449 CNOERR();
450 if (v->tree->flags & SHORTER)
451 NOTE(REG_USHORTEST);
452
453 /* build compacted NFAs for tree, lacons, fast search */
454#ifdef REG_DEBUG
455 if (debug != NULL)
456 fprintf(debug, "\n\n\n========= SEARCH ==========\n");
457#endif
458 /* can sacrifice main NFA now, so use it as work area */
459 (DISCARD) optimize(v->nfa, debug);
460 CNOERR();
461 makesearch(v, v->nfa);
462 CNOERR();
463 compact(v->nfa, &g->search);
464 CNOERR();
465
466 /* looks okay, package it up */
467 re->re_nsub = v->nsubexp;
468 v->re = NULL; /* freev no longer frees re */
469 g->magic = GUTSMAGIC;
470 g->cflags = v->cflags;
471 g->info = re->re_info;
472 g->nsub = re->re_nsub;
473 g->tree = v->tree;
474 v->tree = NULL;
475 g->ntree = v->ntree;
476 g->compare = (v->cflags & REG_ICASE) ? casecmp : cmp;
477 g->lacons = v->lacons;
478 v->lacons = NULL;
479 g->nlacons = v->nlacons;
480
481#ifdef REG_DEBUG
482 if (flags & REG_DUMP)
483 dump(re, stdout);
484#endif
485
486 assert(v->err == 0);
487 return freev(v, 0);
488}
489
490/*
491 * moresubs - enlarge subRE vector
492 */
493static void
494moresubs(struct vars *v,
495 int wanted) /* want enough room for this one */
496{
497 struct subre **p;
498 size_t n;
499
500 assert(wanted > 0 && (size_t) wanted >= v->nsubs);
501 n = (size_t) wanted * 3 / 2 + 1;
502
503 if (v->subs == v->sub10)
504 {
505 p = (struct subre **) MALLOC(n * sizeof(struct subre *));
506 if (p != NULL)
507 memcpy(VS(p), VS(v->subs),
508 v->nsubs * sizeof(struct subre *));
509 }
510 else
511 p = (struct subre **) REALLOC(v->subs, n * sizeof(struct subre *));
512 if (p == NULL)
513 {
514 ERR(REG_ESPACE);
515 return;
516 }
517 v->subs = p;
518 for (p = &v->subs[v->nsubs]; v->nsubs < n; p++, v->nsubs++)
519 *p = NULL;
520 assert(v->nsubs == n);
521 assert((size_t) wanted < v->nsubs);
522}
523
524/*
525 * freev - free vars struct's substructures where necessary
526 *
527 * Optionally does error-number setting, and always returns error code
528 * (if any), to make error-handling code terser.
529 */
530static int
531freev(struct vars *v,
532 int err)
533{
534 if (v->re != NULL)
535 rfree(v->re);
536 if (v->subs != v->sub10)
537 FREE(v->subs);
538 if (v->nfa != NULL)
539 freenfa(v->nfa);
540 if (v->tree != NULL)
541 freesubre(v, v->tree);
542 if (v->treechain != NULL)
543 cleanst(v);
544 if (v->cv != NULL)
545 freecvec(v->cv);
546 if (v->cv2 != NULL)
547 freecvec(v->cv2);
548 if (v->lacons != NULL)
549 freelacons(v->lacons, v->nlacons);
550 ERR(err); /* nop if err==0 */
551
552 return v->err;
553}
554
555/*
556 * makesearch - turn an NFA into a search NFA (implicit prepend of .*?)
557 * NFA must have been optimize()d already.
558 */
559static void
560makesearch(struct vars *v,
561 struct nfa *nfa)
562{
563 struct arc *a;
564 struct arc *b;
565 struct state *pre = nfa->pre;
566 struct state *s;
567 struct state *s2;
568 struct state *slist;
569
570 /* no loops are needed if it's anchored */
571 for (a = pre->outs; a != NULL; a = a->outchain)
572 {
573 assert(a->type == PLAIN);
574 if (a->co != nfa->bos[0] && a->co != nfa->bos[1])
575 break;
576 }
577 if (a != NULL)
578 {
579 /* add implicit .* in front */
580 rainbow(nfa, v->cm, PLAIN, COLORLESS, pre, pre);
581
582 /* and ^* and \A* too -- not always necessary, but harmless */
583 newarc(nfa, PLAIN, nfa->bos[0], pre, pre);
584 newarc(nfa, PLAIN, nfa->bos[1], pre, pre);
585 }
586
587 /*
588 * Now here's the subtle part. Because many REs have no lookback
589 * constraints, often knowing when you were in the pre state tells you
590 * little; it's the next state(s) that are informative. But some of them
591 * may have other inarcs, i.e. it may be possible to make actual progress
592 * and then return to one of them. We must de-optimize such cases,
593 * splitting each such state into progress and no-progress states.
594 */
595
596 /* first, make a list of the states reachable from pre and elsewhere */
597 slist = NULL;
598 for (a = pre->outs; a != NULL; a = a->outchain)
599 {
600 s = a->to;
601 for (b = s->ins; b != NULL; b = b->inchain)
602 {
603 if (b->from != pre)
604 break;
605 }
606
607 /*
608 * We want to mark states as being in the list already by having non
609 * NULL tmp fields, but we can't just store the old slist value in tmp
610 * because that doesn't work for the first such state. Instead, the
611 * first list entry gets its own address in tmp.
612 */
613 if (b != NULL && s->tmp == NULL)
614 {
615 s->tmp = (slist != NULL) ? slist : s;
616 slist = s;
617 }
618 }
619
620 /* do the splits */
621 for (s = slist; s != NULL; s = s2)
622 {
623 s2 = newstate(nfa);
624 NOERR();
625 copyouts(nfa, s, s2);
626 NOERR();
627 for (a = s->ins; a != NULL; a = b)
628 {
629 b = a->inchain;
630 if (a->from != pre)
631 {
632 cparc(nfa, a, a->from, s2);
633 freearc(nfa, a);
634 }
635 }
636 s2 = (s->tmp != s) ? s->tmp : NULL;
637 s->tmp = NULL; /* clean up while we're at it */
638 }
639}
640
641/*
642 * parse - parse an RE
643 *
644 * This is actually just the top level, which parses a bunch of branches
645 * tied together with '|'. They appear in the tree as the left children
646 * of a chain of '|' subres.
647 */
648static struct subre *
649parse(struct vars *v,
650 int stopper, /* EOS or ')' */
651 int type, /* LACON (lookaround subRE) or PLAIN */
652 struct state *init, /* initial state */
653 struct state *final) /* final state */
654{
655 struct state *left; /* scaffolding for branch */
656 struct state *right;
657 struct subre *branches; /* top level */
658 struct subre *branch; /* current branch */
659 struct subre *t; /* temporary */
660 int firstbranch; /* is this the first branch? */
661
662 assert(stopper == ')' || stopper == EOS);
663
664 branches = subre(v, '|', LONGER, init, final);
665 NOERRN();
666 branch = branches;
667 firstbranch = 1;
668 do
669 { /* a branch */
670 if (!firstbranch)
671 {
672 /* need a place to hang it */
673 branch->right = subre(v, '|', LONGER, init, final);
674 NOERRN();
675 branch = branch->right;
676 }
677 firstbranch = 0;
678 left = newstate(v->nfa);
679 right = newstate(v->nfa);
680 NOERRN();
681 EMPTYARC(init, left);
682 EMPTYARC(right, final);
683 NOERRN();
684 branch->left = parsebranch(v, stopper, type, left, right, 0);
685 NOERRN();
686 branch->flags |= UP(branch->flags | branch->left->flags);
687 if ((branch->flags & ~branches->flags) != 0) /* new flags */
688 for (t = branches; t != branch; t = t->right)
689 t->flags |= branch->flags;
690 } while (EAT('|'));
691 assert(SEE(stopper) || SEE(EOS));
692
693 if (!SEE(stopper))
694 {
695 assert(stopper == ')' && SEE(EOS));
696 ERR(REG_EPAREN);
697 }
698
699 /* optimize out simple cases */
700 if (branch == branches)
701 { /* only one branch */
702 assert(branch->right == NULL);
703 t = branch->left;
704 branch->left = NULL;
705 freesubre(v, branches);
706 branches = t;
707 }
708 else if (!MESSY(branches->flags))
709 { /* no interesting innards */
710 freesubre(v, branches->left);
711 branches->left = NULL;
712 freesubre(v, branches->right);
713 branches->right = NULL;
714 branches->op = '=';
715 }
716
717 return branches;
718}
719
720/*
721 * parsebranch - parse one branch of an RE
722 *
723 * This mostly manages concatenation, working closely with parseqatom().
724 * Concatenated things are bundled up as much as possible, with separate
725 * ',' nodes introduced only when necessary due to substructure.
726 */
727static struct subre *
728parsebranch(struct vars *v,
729 int stopper, /* EOS or ')' */
730 int type, /* LACON (lookaround subRE) or PLAIN */
731 struct state *left, /* leftmost state */
732 struct state *right, /* rightmost state */
733 int partial) /* is this only part of a branch? */
734{
735 struct state *lp; /* left end of current construct */
736 int seencontent; /* is there anything in this branch yet? */
737 struct subre *t;
738
739 lp = left;
740 seencontent = 0;
741 t = subre(v, '=', 0, left, right); /* op '=' is tentative */
742 NOERRN();
743 while (!SEE('|') && !SEE(stopper) && !SEE(EOS))
744 {
745 if (seencontent)
746 { /* implicit concat operator */
747 lp = newstate(v->nfa);
748 NOERRN();
749 moveins(v->nfa, right, lp);
750 }
751 seencontent = 1;
752
753 /* NB, recursion in parseqatom() may swallow rest of branch */
754 parseqatom(v, stopper, type, lp, right, t);
755 NOERRN();
756 }
757
758 if (!seencontent)
759 { /* empty branch */
760 if (!partial)
761 NOTE(REG_UUNSPEC);
762 assert(lp == left);
763 EMPTYARC(left, right);
764 }
765
766 return t;
767}
768
769/*
770 * parseqatom - parse one quantified atom or constraint of an RE
771 *
772 * The bookkeeping near the end cooperates very closely with parsebranch();
773 * in particular, it contains a recursion that can involve parsing the rest
774 * of the branch, making this function's name somewhat inaccurate.
775 */
776static void
777parseqatom(struct vars *v,
778 int stopper, /* EOS or ')' */
779 int type, /* LACON (lookaround subRE) or PLAIN */
780 struct state *lp, /* left state to hang it on */
781 struct state *rp, /* right state to hang it on */
782 struct subre *top) /* subtree top */
783{
784 struct state *s; /* temporaries for new states */
785 struct state *s2;
786
787#define ARCV(t, val) newarc(v->nfa, t, val, lp, rp)
788 int m,
789 n;
790 struct subre *atom; /* atom's subtree */
791 struct subre *t;
792 int cap; /* capturing parens? */
793 int latype; /* lookaround constraint type */
794 int subno; /* capturing-parens or backref number */
795 int atomtype;
796 int qprefer; /* quantifier short/long preference */
797 int f;
798 struct subre **atomp; /* where the pointer to atom is */
799
800 /* initial bookkeeping */
801 atom = NULL;
802 assert(lp->nouts == 0); /* must string new code */
803 assert(rp->nins == 0); /* between lp and rp */
804 subno = 0; /* just to shut lint up */
805
806 /* an atom or constraint... */
807 atomtype = v->nexttype;
808 switch (atomtype)
809 {
810 /* first, constraints, which end by returning */
811 case '^':
812 ARCV('^', 1);
813 if (v->cflags & REG_NLANCH)
814 ARCV(BEHIND, v->nlcolor);
815 NEXT();
816 return;
817 break;
818 case '$':
819 ARCV('$', 1);
820 if (v->cflags & REG_NLANCH)
821 ARCV(AHEAD, v->nlcolor);
822 NEXT();
823 return;
824 break;
825 case SBEGIN:
826 ARCV('^', 1); /* BOL */
827 ARCV('^', 0); /* or BOS */
828 NEXT();
829 return;
830 break;
831 case SEND:
832 ARCV('$', 1); /* EOL */
833 ARCV('$', 0); /* or EOS */
834 NEXT();
835 return;
836 break;
837 case '<':
838 wordchrs(v); /* does NEXT() */
839 s = newstate(v->nfa);
840 NOERR();
841 nonword(v, BEHIND, lp, s);
842 word(v, AHEAD, s, rp);
843 return;
844 break;
845 case '>':
846 wordchrs(v); /* does NEXT() */
847 s = newstate(v->nfa);
848 NOERR();
849 word(v, BEHIND, lp, s);
850 nonword(v, AHEAD, s, rp);
851 return;
852 break;
853 case WBDRY:
854 wordchrs(v); /* does NEXT() */
855 s = newstate(v->nfa);
856 NOERR();
857 nonword(v, BEHIND, lp, s);
858 word(v, AHEAD, s, rp);
859 s = newstate(v->nfa);
860 NOERR();
861 word(v, BEHIND, lp, s);
862 nonword(v, AHEAD, s, rp);
863 return;
864 break;
865 case NWBDRY:
866 wordchrs(v); /* does NEXT() */
867 s = newstate(v->nfa);
868 NOERR();
869 word(v, BEHIND, lp, s);
870 word(v, AHEAD, s, rp);
871 s = newstate(v->nfa);
872 NOERR();
873 nonword(v, BEHIND, lp, s);
874 nonword(v, AHEAD, s, rp);
875 return;
876 break;
877 case LACON: /* lookaround constraint */
878 latype = v->nextvalue;
879 NEXT();
880 s = newstate(v->nfa);
881 s2 = newstate(v->nfa);
882 NOERR();
883 t = parse(v, ')', LACON, s, s2);
884 freesubre(v, t); /* internal structure irrelevant */
885 NOERR();
886 assert(SEE(')'));
887 NEXT();
888 processlacon(v, s, s2, latype, lp, rp);
889 return;
890 break;
891 /* then errors, to get them out of the way */
892 case '*':
893 case '+':
894 case '?':
895 case '{':
896 ERR(REG_BADRPT);
897 return;
898 break;
899 default:
900 ERR(REG_ASSERT);
901 return;
902 break;
903 /* then plain characters, and minor variants on that theme */
904 case ')': /* unbalanced paren */
905 if ((v->cflags & REG_ADVANCED) != REG_EXTENDED)
906 {
907 ERR(REG_EPAREN);
908 return;
909 }
910 /* legal in EREs due to specification botch */
911 NOTE(REG_UPBOTCH);
912 /* fall through into case PLAIN */
913 /* FALLTHROUGH */
914 case PLAIN:
915 onechr(v, v->nextvalue, lp, rp);
916 okcolors(v->nfa, v->cm);
917 NOERR();
918 NEXT();
919 break;
920 case '[':
921 if (v->nextvalue == 1)
922 bracket(v, lp, rp);
923 else
924 cbracket(v, lp, rp);
925 assert(SEE(']') || ISERR());
926 NEXT();
927 break;
928 case '.':
929 rainbow(v->nfa, v->cm, PLAIN,
930 (v->cflags & REG_NLSTOP) ? v->nlcolor : COLORLESS,
931 lp, rp);
932 NEXT();
933 break;
934 /* and finally the ugly stuff */
935 case '(': /* value flags as capturing or non */
936 cap = (type == LACON) ? 0 : v->nextvalue;
937 if (cap)
938 {
939 v->nsubexp++;
940 subno = v->nsubexp;
941 if ((size_t) subno >= v->nsubs)
942 moresubs(v, subno);
943 assert((size_t) subno < v->nsubs);
944 }
945 else
946 atomtype = PLAIN; /* something that's not '(' */
947 NEXT();
948 /* need new endpoints because tree will contain pointers */
949 s = newstate(v->nfa);
950 s2 = newstate(v->nfa);
951 NOERR();
952 EMPTYARC(lp, s);
953 EMPTYARC(s2, rp);
954 NOERR();
955 atom = parse(v, ')', type, s, s2);
956 assert(SEE(')') || ISERR());
957 NEXT();
958 NOERR();
959 if (cap)
960 {
961 v->subs[subno] = atom;
962 t = subre(v, '(', atom->flags | CAP, lp, rp);
963 NOERR();
964 t->subno = subno;
965 t->left = atom;
966 atom = t;
967 }
968 /* postpone everything else pending possible {0} */
969 break;
970 case BACKREF: /* the Feature From The Black Lagoon */
971 INSIST(type != LACON, REG_ESUBREG);
972 INSIST(v->nextvalue < v->nsubs, REG_ESUBREG);
973 INSIST(v->subs[v->nextvalue] != NULL, REG_ESUBREG);
974 NOERR();
975 assert(v->nextvalue > 0);
976 atom = subre(v, 'b', BACKR, lp, rp);
977 NOERR();
978 subno = v->nextvalue;
979 atom->subno = subno;
980 EMPTYARC(lp, rp); /* temporarily, so there's something */
981 NEXT();
982 break;
983 }
984
985 /* ...and an atom may be followed by a quantifier */
986 switch (v->nexttype)
987 {
988 case '*':
989 m = 0;
990 n = DUPINF;
991 qprefer = (v->nextvalue) ? LONGER : SHORTER;
992 NEXT();
993 break;
994 case '+':
995 m = 1;
996 n = DUPINF;
997 qprefer = (v->nextvalue) ? LONGER : SHORTER;
998 NEXT();
999 break;
1000 case '?':
1001 m = 0;
1002 n = 1;
1003 qprefer = (v->nextvalue) ? LONGER : SHORTER;
1004 NEXT();
1005 break;
1006 case '{':
1007 NEXT();
1008 m = scannum(v);
1009 if (EAT(','))
1010 {
1011 if (SEE(DIGIT))
1012 n = scannum(v);
1013 else
1014 n = DUPINF;
1015 if (m > n)
1016 {
1017 ERR(REG_BADBR);
1018 return;
1019 }
1020 /* {m,n} exercises preference, even if it's {m,m} */
1021 qprefer = (v->nextvalue) ? LONGER : SHORTER;
1022 }
1023 else
1024 {
1025 n = m;
1026 /* {m} passes operand's preference through */
1027 qprefer = 0;
1028 }
1029 if (!SEE('}'))
1030 { /* catches errors too */
1031 ERR(REG_BADBR);
1032 return;
1033 }
1034 NEXT();
1035 break;
1036 default: /* no quantifier */
1037 m = n = 1;
1038 qprefer = 0;
1039 break;
1040 }
1041
1042 /* annoying special case: {0} or {0,0} cancels everything */
1043 if (m == 0 && n == 0)
1044 {
1045 if (atom != NULL)
1046 freesubre(v, atom);
1047 if (atomtype == '(')
1048 v->subs[subno] = NULL;
1049 delsub(v->nfa, lp, rp);
1050 EMPTYARC(lp, rp);
1051 return;
1052 }
1053
1054 /* if not a messy case, avoid hard part */
1055 assert(!MESSY(top->flags));
1056 f = top->flags | qprefer | ((atom != NULL) ? atom->flags : 0);
1057 if (atomtype != '(' && atomtype != BACKREF && !MESSY(UP(f)))
1058 {
1059 if (!(m == 1 && n == 1))
1060 repeat(v, lp, rp, m, n);
1061 if (atom != NULL)
1062 freesubre(v, atom);
1063 top->flags = f;
1064 return;
1065 }
1066
1067 /*
1068 * hard part: something messy
1069 *
1070 * That is, capturing parens, back reference, short/long clash, or an atom
1071 * with substructure containing one of those.
1072 */
1073
1074 /* now we'll need a subre for the contents even if they're boring */
1075 if (atom == NULL)
1076 {
1077 atom = subre(v, '=', 0, lp, rp);
1078 NOERR();
1079 }
1080
1081 /*----------
1082 * Prepare a general-purpose state skeleton.
1083 *
1084 * In the no-backrefs case, we want this:
1085 *
1086 * [lp] ---> [s] ---prefix---> [begin] ---atom---> [end] ---rest---> [rp]
1087 *
1088 * where prefix is some repetitions of atom. In the general case we need
1089 *
1090 * [lp] ---> [s] ---iterator---> [s2] ---rest---> [rp]
1091 *
1092 * where the iterator wraps around [begin] ---atom---> [end]
1093 *
1094 * We make the s state here for both cases; s2 is made below if needed
1095 *----------
1096 */
1097 s = newstate(v->nfa); /* first, new endpoints for the atom */
1098 s2 = newstate(v->nfa);
1099 NOERR();
1100 moveouts(v->nfa, lp, s);
1101 moveins(v->nfa, rp, s2);
1102 NOERR();
1103 atom->begin = s;
1104 atom->end = s2;
1105 s = newstate(v->nfa); /* set up starting state */
1106 NOERR();
1107 EMPTYARC(lp, s);
1108 NOERR();
1109
1110 /* break remaining subRE into x{...} and what follows */
1111 t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp);
1112 NOERR();
1113 t->left = atom;
1114 atomp = &t->left;
1115
1116 /* here we should recurse... but we must postpone that to the end */
1117
1118 /* split top into prefix and remaining */
1119 assert(top->op == '=' && top->left == NULL && top->right == NULL);
1120 top->left = subre(v, '=', top->flags, top->begin, lp);
1121 NOERR();
1122 top->op = '.';
1123 top->right = t;
1124
1125 /* if it's a backref, now is the time to replicate the subNFA */
1126 if (atomtype == BACKREF)
1127 {
1128 assert(atom->begin->nouts == 1); /* just the EMPTY */
1129 delsub(v->nfa, atom->begin, atom->end);
1130 assert(v->subs[subno] != NULL);
1131
1132 /*
1133 * And here's why the recursion got postponed: it must wait until the
1134 * skeleton is filled in, because it may hit a backref that wants to
1135 * copy the filled-in skeleton.
1136 */
1137 dupnfa(v->nfa, v->subs[subno]->begin, v->subs[subno]->end,
1138 atom->begin, atom->end);
1139 NOERR();
1140 }
1141
1142 /*
1143 * It's quantifier time. If the atom is just a backref, we'll let it deal
1144 * with quantifiers internally.
1145 */
1146 if (atomtype == BACKREF)
1147 {
1148 /* special case: backrefs have internal quantifiers */
1149 EMPTYARC(s, atom->begin); /* empty prefix */
1150 /* just stuff everything into atom */
1151 repeat(v, atom->begin, atom->end, m, n);
1152 atom->min = (short) m;
1153 atom->max = (short) n;
1154 atom->flags |= COMBINE(qprefer, atom->flags);
1155 /* rest of branch can be strung starting from atom->end */
1156 s2 = atom->end;
1157 }
1158 else if (m == 1 && n == 1 &&
1159 (qprefer == 0 ||
1160 (atom->flags & (LONGER | SHORTER | MIXED)) == 0 ||
1161 qprefer == (atom->flags & (LONGER | SHORTER | MIXED))))
1162 {
1163 /* no/vacuous quantifier: done */
1164 EMPTYARC(s, atom->begin); /* empty prefix */
1165 /* rest of branch can be strung starting from atom->end */
1166 s2 = atom->end;
1167 }
1168 else if (m > 0 && !(atom->flags & BACKR))
1169 {
1170 /*
1171 * If there's no backrefs involved, we can turn x{m,n} into
1172 * x{m-1,n-1}x, with capturing parens in only the second x. This is
1173 * valid because we only care about capturing matches from the final
1174 * iteration of the quantifier. It's a win because we can implement
1175 * the backref-free left side as a plain DFA node, since we don't
1176 * really care where its submatches are.
1177 */
1178 dupnfa(v->nfa, atom->begin, atom->end, s, atom->begin);
1179 assert(m >= 1 && m != DUPINF && n >= 1);
1180 repeat(v, s, atom->begin, m - 1, (n == DUPINF) ? n : n - 1);
1181 f = COMBINE(qprefer, atom->flags);
1182 t = subre(v, '.', f, s, atom->end); /* prefix and atom */
1183 NOERR();
1184 t->left = subre(v, '=', PREF(f), s, atom->begin);
1185 NOERR();
1186 t->right = atom;
1187 *atomp = t;
1188 /* rest of branch can be strung starting from atom->end */
1189 s2 = atom->end;
1190 }
1191 else
1192 {
1193 /* general case: need an iteration node */
1194 s2 = newstate(v->nfa);
1195 NOERR();
1196 moveouts(v->nfa, atom->end, s2);
1197 NOERR();
1198 dupnfa(v->nfa, atom->begin, atom->end, s, s2);
1199 repeat(v, s, s2, m, n);
1200 f = COMBINE(qprefer, atom->flags);
1201 t = subre(v, '*', f, s, s2);
1202 NOERR();
1203 t->min = (short) m;
1204 t->max = (short) n;
1205 t->left = atom;
1206 *atomp = t;
1207 /* rest of branch is to be strung from iteration's end state */
1208 }
1209
1210 /* and finally, look after that postponed recursion */
1211 t = top->right;
1212 if (!(SEE('|') || SEE(stopper) || SEE(EOS)))
1213 t->right = parsebranch(v, stopper, type, s2, rp, 1);
1214 else
1215 {
1216 EMPTYARC(s2, rp);
1217 t->right = subre(v, '=', 0, s2, rp);
1218 }
1219 NOERR();
1220 assert(SEE('|') || SEE(stopper) || SEE(EOS));
1221 t->flags |= COMBINE(t->flags, t->right->flags);
1222 top->flags |= COMBINE(top->flags, t->flags);
1223}
1224
1225/*
1226 * nonword - generate arcs for non-word-character ahead or behind
1227 */
1228static void
1229nonword(struct vars *v,
1230 int dir, /* AHEAD or BEHIND */
1231 struct state *lp,
1232 struct state *rp)
1233{
1234 int anchor = (dir == AHEAD) ? '$' : '^';
1235
1236 assert(dir == AHEAD || dir == BEHIND);
1237 newarc(v->nfa, anchor, 1, lp, rp);
1238 newarc(v->nfa, anchor, 0, lp, rp);
1239 colorcomplement(v->nfa, v->cm, dir, v->wordchrs, lp, rp);
1240 /* (no need for special attention to \n) */
1241}
1242
1243/*
1244 * word - generate arcs for word character ahead or behind
1245 */
1246static void
1247word(struct vars *v,
1248 int dir, /* AHEAD or BEHIND */
1249 struct state *lp,
1250 struct state *rp)
1251{
1252 assert(dir == AHEAD || dir == BEHIND);
1253 cloneouts(v->nfa, v->wordchrs, lp, rp, dir);
1254 /* (no need for special attention to \n) */
1255}
1256
1257/*
1258 * scannum - scan a number
1259 */
1260static int /* value, <= DUPMAX */
1261scannum(struct vars *v)
1262{
1263 int n = 0;
1264
1265 while (SEE(DIGIT) && n < DUPMAX)
1266 {
1267 n = n * 10 + v->nextvalue;
1268 NEXT();
1269 }
1270 if (SEE(DIGIT) || n > DUPMAX)
1271 {
1272 ERR(REG_BADBR);
1273 return 0;
1274 }
1275 return n;
1276}
1277
1278/*
1279 * repeat - replicate subNFA for quantifiers
1280 *
1281 * The sub-NFA strung from lp to rp is modified to represent m to n
1282 * repetitions of its initial contents.
1283 *
1284 * The duplication sequences used here are chosen carefully so that any
1285 * pointers starting out pointing into the subexpression end up pointing into
1286 * the last occurrence. (Note that it may not be strung between the same
1287 * left and right end states, however!) This used to be important for the
1288 * subRE tree, although the important bits are now handled by the in-line
1289 * code in parse(), and when this is called, it doesn't matter any more.
1290 */
1291static void
1292repeat(struct vars *v,
1293 struct state *lp,
1294 struct state *rp,
1295 int m,
1296 int n)
1297{
1298#define SOME 2
1299#define INF 3
1300#define PAIR(x, y) ((x)*4 + (y))
1301#define REDUCE(x) ( ((x) == DUPINF) ? INF : (((x) > 1) ? SOME : (x)) )
1302 const int rm = REDUCE(m);
1303 const int rn = REDUCE(n);
1304 struct state *s;
1305 struct state *s2;
1306
1307 switch (PAIR(rm, rn))
1308 {
1309 case PAIR(0, 0): /* empty string */
1310 delsub(v->nfa, lp, rp);
1311 EMPTYARC(lp, rp);
1312 break;
1313 case PAIR(0, 1): /* do as x| */
1314 EMPTYARC(lp, rp);
1315 break;
1316 case PAIR(0, SOME): /* do as x{1,n}| */
1317 repeat(v, lp, rp, 1, n);
1318 NOERR();
1319 EMPTYARC(lp, rp);
1320 break;
1321 case PAIR(0, INF): /* loop x around */
1322 s = newstate(v->nfa);
1323 NOERR();
1324 moveouts(v->nfa, lp, s);
1325 moveins(v->nfa, rp, s);
1326 EMPTYARC(lp, s);
1327 EMPTYARC(s, rp);
1328 break;
1329 case PAIR(1, 1): /* no action required */
1330 break;
1331 case PAIR(1, SOME): /* do as x{0,n-1}x = (x{1,n-1}|)x */
1332 s = newstate(v->nfa);
1333 NOERR();
1334 moveouts(v->nfa, lp, s);
1335 dupnfa(v->nfa, s, rp, lp, s);
1336 NOERR();
1337 repeat(v, lp, s, 1, n - 1);
1338 NOERR();
1339 EMPTYARC(lp, s);
1340 break;
1341 case PAIR(1, INF): /* add loopback arc */
1342 s = newstate(v->nfa);
1343 s2 = newstate(v->nfa);
1344 NOERR();
1345 moveouts(v->nfa, lp, s);
1346 moveins(v->nfa, rp, s2);
1347 EMPTYARC(lp, s);
1348 EMPTYARC(s2, rp);
1349 EMPTYARC(s2, s);
1350 break;
1351 case PAIR(SOME, SOME): /* do as x{m-1,n-1}x */
1352 s = newstate(v->nfa);
1353 NOERR();
1354 moveouts(v->nfa, lp, s);
1355 dupnfa(v->nfa, s, rp, lp, s);
1356 NOERR();
1357 repeat(v, lp, s, m - 1, n - 1);
1358 break;
1359 case PAIR(SOME, INF): /* do as x{m-1,}x */
1360 s = newstate(v->nfa);
1361 NOERR();
1362 moveouts(v->nfa, lp, s);
1363 dupnfa(v->nfa, s, rp, lp, s);
1364 NOERR();
1365 repeat(v, lp, s, m - 1, n);
1366 break;
1367 default:
1368 ERR(REG_ASSERT);
1369 break;
1370 }
1371}
1372
1373/*
1374 * bracket - handle non-complemented bracket expression
1375 * Also called from cbracket for complemented bracket expressions.
1376 */
1377static void
1378bracket(struct vars *v,
1379 struct state *lp,
1380 struct state *rp)
1381{
1382 assert(SEE('['));
1383 NEXT();
1384 while (!SEE(']') && !SEE(EOS))
1385 brackpart(v, lp, rp);
1386 assert(SEE(']') || ISERR());
1387 okcolors(v->nfa, v->cm);
1388}
1389
1390/*
1391 * cbracket - handle complemented bracket expression
1392 * We do it by calling bracket() with dummy endpoints, and then complementing
1393 * the result. The alternative would be to invoke rainbow(), and then delete
1394 * arcs as the b.e. is seen... but that gets messy.
1395 */
1396static void
1397cbracket(struct vars *v,
1398 struct state *lp,
1399 struct state *rp)
1400{
1401 struct state *left = newstate(v->nfa);
1402 struct state *right = newstate(v->nfa);
1403
1404 NOERR();
1405 bracket(v, left, right);
1406 if (v->cflags & REG_NLSTOP)
1407 newarc(v->nfa, PLAIN, v->nlcolor, left, right);
1408 NOERR();
1409
1410 assert(lp->nouts == 0); /* all outarcs will be ours */
1411
1412 /*
1413 * Easy part of complementing, and all there is to do since the MCCE code
1414 * was removed.
1415 */
1416 colorcomplement(v->nfa, v->cm, PLAIN, left, lp, rp);
1417 NOERR();
1418 dropstate(v->nfa, left);
1419 assert(right->nins == 0);
1420 freestate(v->nfa, right);
1421}
1422
1423/*
1424 * brackpart - handle one item (or range) within a bracket expression
1425 */
1426static void
1427brackpart(struct vars *v,
1428 struct state *lp,
1429 struct state *rp)
1430{
1431 chr startc;
1432 chr endc;
1433 struct cvec *cv;
1434 const chr *startp;
1435 const chr *endp;
1436 chr c[1];
1437
1438 /* parse something, get rid of special cases, take shortcuts */
1439 switch (v->nexttype)
1440 {
1441 case RANGE: /* a-b-c or other botch */
1442 ERR(REG_ERANGE);
1443 return;
1444 break;
1445 case PLAIN:
1446 c[0] = v->nextvalue;
1447 NEXT();
1448 /* shortcut for ordinary chr (not range) */
1449 if (!SEE(RANGE))
1450 {
1451 onechr(v, c[0], lp, rp);
1452 return;
1453 }
1454 startc = element(v, c, c + 1);
1455 NOERR();
1456 break;
1457 case COLLEL:
1458 startp = v->now;
1459 endp = scanplain(v);
1460 INSIST(startp < endp, REG_ECOLLATE);
1461 NOERR();
1462 startc = element(v, startp, endp);
1463 NOERR();
1464 break;
1465 case ECLASS:
1466 startp = v->now;
1467 endp = scanplain(v);
1468 INSIST(startp < endp, REG_ECOLLATE);
1469 NOERR();
1470 startc = element(v, startp, endp);
1471 NOERR();
1472 cv = eclass(v, startc, (v->cflags & REG_ICASE));
1473 NOERR();
1474 subcolorcvec(v, cv, lp, rp);
1475 return;
1476 break;
1477 case CCLASS:
1478 startp = v->now;
1479 endp = scanplain(v);
1480 INSIST(startp < endp, REG_ECTYPE);
1481 NOERR();
1482 cv = cclass(v, startp, endp, (v->cflags & REG_ICASE));
1483 NOERR();
1484 subcolorcvec(v, cv, lp, rp);
1485 return;
1486 break;
1487 default:
1488 ERR(REG_ASSERT);
1489 return;
1490 break;
1491 }
1492
1493 if (SEE(RANGE))
1494 {
1495 NEXT();
1496 switch (v->nexttype)
1497 {
1498 case PLAIN:
1499 case RANGE:
1500 c[0] = v->nextvalue;
1501 NEXT();
1502 endc = element(v, c, c + 1);
1503 NOERR();
1504 break;
1505 case COLLEL:
1506 startp = v->now;
1507 endp = scanplain(v);
1508 INSIST(startp < endp, REG_ECOLLATE);
1509 NOERR();
1510 endc = element(v, startp, endp);
1511 NOERR();
1512 break;
1513 default:
1514 ERR(REG_ERANGE);
1515 return;
1516 break;
1517 }
1518 }
1519 else
1520 endc = startc;
1521
1522 /*
1523 * Ranges are unportable. Actually, standard C does guarantee that digits
1524 * are contiguous, but making that an exception is just too complicated.
1525 */
1526 if (startc != endc)
1527 NOTE(REG_UUNPORT);
1528 cv = range(v, startc, endc, (v->cflags & REG_ICASE));
1529 NOERR();
1530 subcolorcvec(v, cv, lp, rp);
1531}
1532
1533/*
1534 * scanplain - scan PLAIN contents of [. etc.
1535 *
1536 * Certain bits of trickery in lex.c know that this code does not try
1537 * to look past the final bracket of the [. etc.
1538 */
1539static const chr * /* just after end of sequence */
1540scanplain(struct vars *v)
1541{
1542 const chr *endp;
1543
1544 assert(SEE(COLLEL) || SEE(ECLASS) || SEE(CCLASS));
1545 NEXT();
1546
1547 endp = v->now;
1548 while (SEE(PLAIN))
1549 {
1550 endp = v->now;
1551 NEXT();
1552 }
1553
1554 assert(SEE(END) || ISERR());
1555 NEXT();
1556
1557 return endp;
1558}
1559
1560/*
1561 * onechr - fill in arcs for a plain character, and possible case complements
1562 * This is mostly a shortcut for efficient handling of the common case.
1563 */
1564static void
1565onechr(struct vars *v,
1566 chr c,
1567 struct state *lp,
1568 struct state *rp)
1569{
1570 if (!(v->cflags & REG_ICASE))
1571 {
1572 color lastsubcolor = COLORLESS;
1573
1574 subcoloronechr(v, c, lp, rp, &lastsubcolor);
1575 return;
1576 }
1577
1578 /* rats, need general case anyway... */
1579 subcolorcvec(v, allcases(v, c), lp, rp);
1580}
1581
1582/*
1583 * wordchrs - set up word-chr list for word-boundary stuff, if needed
1584 *
1585 * The list is kept as a bunch of arcs between two dummy states; it's
1586 * disposed of by the unreachable-states sweep in NFA optimization.
1587 * Does NEXT(). Must not be called from any unusual lexical context.
1588 * This should be reconciled with the \w etc. handling in lex.c, and
1589 * should be cleaned up to reduce dependencies on input scanning.
1590 */
1591static void
1592wordchrs(struct vars *v)
1593{
1594 struct state *left;
1595 struct state *right;
1596
1597 if (v->wordchrs != NULL)
1598 {
1599 NEXT(); /* for consistency */
1600 return;
1601 }
1602
1603 left = newstate(v->nfa);
1604 right = newstate(v->nfa);
1605 NOERR();
1606 /* fine point: implemented with [::], and lexer will set REG_ULOCALE */
1607 lexword(v);
1608 NEXT();
1609 assert(v->savenow != NULL && SEE('['));
1610 bracket(v, left, right);
1611 assert((v->savenow != NULL && SEE(']')) || ISERR());
1612 NEXT();
1613 NOERR();
1614 v->wordchrs = left;
1615}
1616
1617/*
1618 * processlacon - generate the NFA representation of a LACON
1619 *
1620 * In the general case this is just newlacon() + newarc(), but some cases
1621 * can be optimized.
1622 */
1623static void
1624processlacon(struct vars *v,
1625 struct state *begin, /* start of parsed LACON sub-re */
1626 struct state *end, /* end of parsed LACON sub-re */
1627 int latype,
1628 struct state *lp, /* left state to hang it on */
1629 struct state *rp) /* right state to hang it on */
1630{
1631 struct state *s1;
1632 int n;
1633
1634 /*
1635 * Check for lookaround RE consisting of a single plain color arc (or set
1636 * of arcs); this would typically be a simple chr or a bracket expression.
1637 */
1638 s1 = single_color_transition(begin, end);
1639 switch (latype)
1640 {
1641 case LATYPE_AHEAD_POS:
1642 /* If lookahead RE is just colorset C, convert to AHEAD(C) */
1643 if (s1 != NULL)
1644 {
1645 cloneouts(v->nfa, s1, lp, rp, AHEAD);
1646 return;
1647 }
1648 break;
1649 case LATYPE_AHEAD_NEG:
1650 /* If lookahead RE is just colorset C, convert to AHEAD(^C)|$ */
1651 if (s1 != NULL)
1652 {
1653 colorcomplement(v->nfa, v->cm, AHEAD, s1, lp, rp);
1654 newarc(v->nfa, '$', 1, lp, rp);
1655 newarc(v->nfa, '$', 0, lp, rp);
1656 return;
1657 }
1658 break;
1659 case LATYPE_BEHIND_POS:
1660 /* If lookbehind RE is just colorset C, convert to BEHIND(C) */
1661 if (s1 != NULL)
1662 {
1663 cloneouts(v->nfa, s1, lp, rp, BEHIND);
1664 return;
1665 }
1666 break;
1667 case LATYPE_BEHIND_NEG:
1668 /* If lookbehind RE is just colorset C, convert to BEHIND(^C)|^ */
1669 if (s1 != NULL)
1670 {
1671 colorcomplement(v->nfa, v->cm, BEHIND, s1, lp, rp);
1672 newarc(v->nfa, '^', 1, lp, rp);
1673 newarc(v->nfa, '^', 0, lp, rp);
1674 return;
1675 }
1676 break;
1677 default:
1678 assert(NOTREACHED);
1679 }
1680
1681 /* General case: we need a LACON subre and arc */
1682 n = newlacon(v, begin, end, latype);
1683 newarc(v->nfa, LACON, n, lp, rp);
1684}
1685
1686/*
1687 * subre - allocate a subre
1688 */
1689static struct subre *
1690subre(struct vars *v,
1691 int op,
1692 int flags,
1693 struct state *begin,
1694 struct state *end)
1695{
1696 struct subre *ret = v->treefree;
1697
1698 /*
1699 * Checking for stack overflow here is sufficient to protect parse() and
1700 * its recursive subroutines.
1701 */
1702 if (STACK_TOO_DEEP(v->re))
1703 {
1704 ERR(REG_ETOOBIG);
1705 return NULL;
1706 }
1707
1708 if (ret != NULL)
1709 v->treefree = ret->left;
1710 else
1711 {
1712 ret = (struct subre *) MALLOC(sizeof(struct subre));
1713 if (ret == NULL)
1714 {
1715 ERR(REG_ESPACE);
1716 return NULL;
1717 }
1718 ret->chain = v->treechain;
1719 v->treechain = ret;
1720 }
1721
1722 assert(strchr("=b|.*(", op) != NULL);
1723
1724 ret->op = op;
1725 ret->flags = flags;
1726 ret->id = 0; /* will be assigned later */
1727 ret->subno = 0;
1728 ret->min = ret->max = 1;
1729 ret->left = NULL;
1730 ret->right = NULL;
1731 ret->begin = begin;
1732 ret->end = end;
1733 ZAPCNFA(ret->cnfa);
1734
1735 return ret;
1736}
1737
1738/*
1739 * freesubre - free a subRE subtree
1740 */
1741static void
1742freesubre(struct vars *v, /* might be NULL */
1743 struct subre *sr)
1744{
1745 if (sr == NULL)
1746 return;
1747
1748 if (sr->left != NULL)
1749 freesubre(v, sr->left);
1750 if (sr->right != NULL)
1751 freesubre(v, sr->right);
1752
1753 freesrnode(v, sr);
1754}
1755
1756/*
1757 * freesrnode - free one node in a subRE subtree
1758 */
1759static void
1760freesrnode(struct vars *v, /* might be NULL */
1761 struct subre *sr)
1762{
1763 if (sr == NULL)
1764 return;
1765
1766 if (!NULLCNFA(sr->cnfa))
1767 freecnfa(&sr->cnfa);
1768 sr->flags = 0;
1769
1770 if (v != NULL && v->treechain != NULL)
1771 {
1772 /* we're still parsing, maybe we can reuse the subre */
1773 sr->left = v->treefree;
1774 v->treefree = sr;
1775 }
1776 else
1777 FREE(sr);
1778}
1779
1780/*
1781 * optst - optimize a subRE subtree
1782 */
1783static void
1784optst(struct vars *v,
1785 struct subre *t)
1786{
1787 /*
1788 * DGP (2007-11-13): I assume it was the programmer's intent to eventually
1789 * come back and add code to optimize subRE trees, but the routine coded
1790 * just spends effort traversing the tree and doing nothing. We can do
1791 * nothing with less effort.
1792 */
1793 return;
1794}
1795
1796/*
1797 * numst - number tree nodes (assigning "id" indexes)
1798 */
1799static int /* next number */
1800numst(struct subre *t,
1801 int start) /* starting point for subtree numbers */
1802{
1803 int i;
1804
1805 assert(t != NULL);
1806
1807 i = start;
1808 t->id = (short) i++;
1809 if (t->left != NULL)
1810 i = numst(t->left, i);
1811 if (t->right != NULL)
1812 i = numst(t->right, i);
1813 return i;
1814}
1815
1816/*
1817 * markst - mark tree nodes as INUSE
1818 *
1819 * Note: this is a great deal more subtle than it looks. During initial
1820 * parsing of a regex, all subres are linked into the treechain list;
1821 * discarded ones are also linked into the treefree list for possible reuse.
1822 * After we are done creating all subres required for a regex, we run markst()
1823 * then cleanst(), which results in discarding all subres not reachable from
1824 * v->tree. We then clear v->treechain, indicating that subres must be found
1825 * by descending from v->tree. This changes the behavior of freesubre(): it
1826 * will henceforth FREE() unwanted subres rather than sticking them into the
1827 * treefree list. (Doing that any earlier would result in dangling links in
1828 * the treechain list.) This all means that freev() will clean up correctly
1829 * if invoked before or after markst()+cleanst(); but it would not work if
1830 * called partway through this state conversion, so we mustn't error out
1831 * in or between these two functions.
1832 */
1833static void
1834markst(struct subre *t)
1835{
1836 assert(t != NULL);
1837
1838 t->flags |= INUSE;
1839 if (t->left != NULL)
1840 markst(t->left);
1841 if (t->right != NULL)
1842 markst(t->right);
1843}
1844
1845/*
1846 * cleanst - free any tree nodes not marked INUSE
1847 */
1848static void
1849cleanst(struct vars *v)
1850{
1851 struct subre *t;
1852 struct subre *next;
1853
1854 for (t = v->treechain; t != NULL; t = next)
1855 {
1856 next = t->chain;
1857 if (!(t->flags & INUSE))
1858 FREE(t);
1859 }
1860 v->treechain = NULL;
1861 v->treefree = NULL; /* just on general principles */
1862}
1863
1864/*
1865 * nfatree - turn a subRE subtree into a tree of compacted NFAs
1866 */
1867static long /* optimize results from top node */
1868nfatree(struct vars *v,
1869 struct subre *t,
1870 FILE *f) /* for debug output */
1871{
1872 assert(t != NULL && t->begin != NULL);
1873
1874 if (t->left != NULL)
1875 (DISCARD) nfatree(v, t->left, f);
1876 if (t->right != NULL)
1877 (DISCARD) nfatree(v, t->right, f);
1878
1879 return nfanode(v, t, 0, f);
1880}
1881
1882/*
1883 * nfanode - do one NFA for nfatree or lacons
1884 *
1885 * If converttosearch is true, apply makesearch() to the NFA.
1886 */
1887static long /* optimize results */
1888nfanode(struct vars *v,
1889 struct subre *t,
1890 int converttosearch,
1891 FILE *f) /* for debug output */
1892{
1893 struct nfa *nfa;
1894 long ret = 0;
1895
1896 assert(t->begin != NULL);
1897
1898#ifdef REG_DEBUG
1899 if (f != NULL)
1900 {
1901 char idbuf[50];
1902
1903 fprintf(f, "\n\n\n========= TREE NODE %s ==========\n",
1904 stid(t, idbuf, sizeof(idbuf)));
1905 }
1906#endif
1907 nfa = newnfa(v, v->cm, v->nfa);
1908 NOERRZ();
1909 dupnfa(nfa, t->begin, t->end, nfa->init, nfa->final);
1910 if (!ISERR())
1911 specialcolors(nfa);
1912 if (!ISERR())
1913 ret = optimize(nfa, f);
1914 if (converttosearch && !ISERR())
1915 makesearch(v, nfa);
1916 if (!ISERR())
1917 compact(nfa, &t->cnfa);
1918
1919 freenfa(nfa);
1920 return ret;
1921}
1922
1923/*
1924 * newlacon - allocate a lookaround-constraint subRE
1925 */
1926static int /* lacon number */
1927newlacon(struct vars *v,
1928 struct state *begin,
1929 struct state *end,
1930 int latype)
1931{
1932 int n;
1933 struct subre *newlacons;
1934 struct subre *sub;
1935
1936 if (v->nlacons == 0)
1937 {
1938 n = 1; /* skip 0th */
1939 newlacons = (struct subre *) MALLOC(2 * sizeof(struct subre));
1940 }
1941 else
1942 {
1943 n = v->nlacons;
1944 newlacons = (struct subre *) REALLOC(v->lacons,
1945 (n + 1) * sizeof(struct subre));
1946 }
1947 if (newlacons == NULL)
1948 {
1949 ERR(REG_ESPACE);
1950 return 0;
1951 }
1952 v->lacons = newlacons;
1953 v->nlacons = n + 1;
1954 sub = &v->lacons[n];
1955 sub->begin = begin;
1956 sub->end = end;
1957 sub->subno = latype;
1958 ZAPCNFA(sub->cnfa);
1959 return n;
1960}
1961
1962/*
1963 * freelacons - free lookaround-constraint subRE vector
1964 */
1965static void
1966freelacons(struct subre *subs,
1967 int n)
1968{
1969 struct subre *sub;
1970 int i;
1971
1972 assert(n > 0);
1973 for (sub = subs + 1, i = n - 1; i > 0; sub++, i--) /* no 0th */
1974 if (!NULLCNFA(sub->cnfa))
1975 freecnfa(&sub->cnfa);
1976 FREE(subs);
1977}
1978
1979/*
1980 * rfree - free a whole RE (insides of regfree)
1981 */
1982static void
1983rfree(regex_t *re)
1984{
1985 struct guts *g;
1986
1987 if (re == NULL || re->re_magic != REMAGIC)
1988 return;
1989
1990 re->re_magic = 0; /* invalidate RE */
1991 g = (struct guts *) re->re_guts;
1992 re->re_guts = NULL;
1993 re->re_fns = NULL;
1994 if (g != NULL)
1995 {
1996 g->magic = 0;
1997 freecm(&g->cmap);
1998 if (g->tree != NULL)
1999 freesubre((struct vars *) NULL, g->tree);
2000 if (g->lacons != NULL)
2001 freelacons(g->lacons, g->nlacons);
2002 if (!NULLCNFA(g->search))
2003 freecnfa(&g->search);
2004 FREE(g);
2005 }
2006}
2007
2008/*
2009 * rcancelrequested - check for external request to cancel regex operation
2010 *
2011 * Return nonzero to fail the operation with error code REG_CANCEL,
2012 * zero to keep going
2013 *
2014 * The current implementation is Postgres-specific. If we ever get around
2015 * to splitting the regex code out as a standalone library, there will need
2016 * to be some API to let applications define a callback function for this.
2017 */
2018static int
2019rcancelrequested(void)
2020{
2021 return InterruptPending && (QueryCancelPending || ProcDiePending);
2022}
2023
2024/*
2025 * rstacktoodeep - check for stack getting dangerously deep
2026 *
2027 * Return nonzero to fail the operation with error code REG_ETOOBIG,
2028 * zero to keep going
2029 *
2030 * The current implementation is Postgres-specific. If we ever get around
2031 * to splitting the regex code out as a standalone library, there will need
2032 * to be some API to let applications define a callback function for this.
2033 */
2034static int
2035rstacktoodeep(void)
2036{
2037 return stack_is_too_deep();
2038}
2039
2040#ifdef REG_DEBUG
2041
2042/*
2043 * dump - dump an RE in human-readable form
2044 */
2045static void
2046dump(regex_t *re,
2047 FILE *f)
2048{
2049 struct guts *g;
2050 int i;
2051
2052 if (re->re_magic != REMAGIC)
2053 fprintf(f, "bad magic number (0x%x not 0x%x)\n", re->re_magic,
2054 REMAGIC);
2055 if (re->re_guts == NULL)
2056 {
2057 fprintf(f, "NULL guts!!!\n");
2058 return;
2059 }
2060 g = (struct guts *) re->re_guts;
2061 if (g->magic != GUTSMAGIC)
2062 fprintf(f, "bad guts magic number (0x%x not 0x%x)\n", g->magic,
2063 GUTSMAGIC);
2064
2065 fprintf(f, "\n\n\n========= DUMP ==========\n");
2066 fprintf(f, "nsub %d, info 0%lo, csize %d, ntree %d\n",
2067 (int) re->re_nsub, re->re_info, re->re_csize, g->ntree);
2068
2069 dumpcolors(&g->cmap, f);
2070 if (!NULLCNFA(g->search))
2071 {
2072 fprintf(f, "\nsearch:\n");
2073 dumpcnfa(&g->search, f);
2074 }
2075 for (i = 1; i < g->nlacons; i++)
2076 {
2077 struct subre *lasub = &g->lacons[i];
2078 const char *latype;
2079
2080 switch (lasub->subno)
2081 {
2082 case LATYPE_AHEAD_POS:
2083 latype = "positive lookahead";
2084 break;
2085 case LATYPE_AHEAD_NEG:
2086 latype = "negative lookahead";
2087 break;
2088 case LATYPE_BEHIND_POS:
2089 latype = "positive lookbehind";
2090 break;
2091 case LATYPE_BEHIND_NEG:
2092 latype = "negative lookbehind";
2093 break;
2094 default:
2095 latype = "???";
2096 break;
2097 }
2098 fprintf(f, "\nla%d (%s):\n", i, latype);
2099 dumpcnfa(&lasub->cnfa, f);
2100 }
2101 fprintf(f, "\n");
2102 dumpst(g->tree, f, 0);
2103}
2104
2105/*
2106 * dumpst - dump a subRE tree
2107 */
2108static void
2109dumpst(struct subre *t,
2110 FILE *f,
2111 int nfapresent) /* is the original NFA still around? */
2112{
2113 if (t == NULL)
2114 fprintf(f, "null tree\n");
2115 else
2116 stdump(t, f, nfapresent);
2117 fflush(f);
2118}
2119
2120/*
2121 * stdump - recursive guts of dumpst
2122 */
2123static void
2124stdump(struct subre *t,
2125 FILE *f,
2126 int nfapresent) /* is the original NFA still around? */
2127{
2128 char idbuf[50];
2129
2130 fprintf(f, "%s. `%c'", stid(t, idbuf, sizeof(idbuf)), t->op);
2131 if (t->flags & LONGER)
2132 fprintf(f, " longest");
2133 if (t->flags & SHORTER)
2134 fprintf(f, " shortest");
2135 if (t->flags & MIXED)
2136 fprintf(f, " hasmixed");
2137 if (t->flags & CAP)
2138 fprintf(f, " hascapture");
2139 if (t->flags & BACKR)
2140 fprintf(f, " hasbackref");
2141 if (!(t->flags & INUSE))
2142 fprintf(f, " UNUSED");
2143 if (t->subno != 0)
2144 fprintf(f, " (#%d)", t->subno);
2145 if (t->min != 1 || t->max != 1)
2146 {
2147 fprintf(f, " {%d,", t->min);
2148 if (t->max != DUPINF)
2149 fprintf(f, "%d", t->max);
2150 fprintf(f, "}");
2151 }
2152 if (nfapresent)
2153 fprintf(f, " %ld-%ld", (long) t->begin->no, (long) t->end->no);
2154 if (t->left != NULL)
2155 fprintf(f, " L:%s", stid(t->left, idbuf, sizeof(idbuf)));
2156 if (t->right != NULL)
2157 fprintf(f, " R:%s", stid(t->right, idbuf, sizeof(idbuf)));
2158 if (!NULLCNFA(t->cnfa))
2159 {
2160 fprintf(f, "\n");
2161 dumpcnfa(&t->cnfa, f);
2162 }
2163 fprintf(f, "\n");
2164 if (t->left != NULL)
2165 stdump(t->left, f, nfapresent);
2166 if (t->right != NULL)
2167 stdump(t->right, f, nfapresent);
2168}
2169
2170/*
2171 * stid - identify a subtree node for dumping
2172 */
2173static const char * /* points to buf or constant string */
2174stid(struct subre *t,
2175 char *buf,
2176 size_t bufsize)
2177{
2178 /* big enough for hex int or decimal t->id? */
2179 if (bufsize < sizeof(void *) * 2 + 3 || bufsize < sizeof(t->id) * 3 + 1)
2180 return "unable";
2181 if (t->id != 0)
2182 sprintf(buf, "%d", t->id);
2183 else
2184 sprintf(buf, "%p", t);
2185 return buf;
2186}
2187#endif /* REG_DEBUG */
2188
2189
2190#include "regc_lex.c"
2191#include "regc_color.c"
2192#include "regc_nfa.c"
2193#include "regc_cvec.c"
2194#include "regc_pg_locale.c"
2195#include "regc_locale.c"
2196