PostgreSQL Source Code  git master
regcomp.c
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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 === */
41 static void moresubs(struct vars *v, int wanted);
42 static int freev(struct vars *v, int err);
43 static void makesearch(struct vars *v, struct nfa *nfa);
44 static struct subre *parse(struct vars *v, int stopper, int type,
45  struct state *init, struct state *final);
46 static struct subre *parsebranch(struct vars *v, int stopper, int type,
47  struct state *left, struct state *right,
48  int partial);
49 static struct subre *parseqatom(struct vars *v, int stopper, int type,
50  struct state *lp, struct state *rp,
51  struct subre *top);
52 static void nonword(struct vars *v, int dir, struct state *lp,
53  struct state *rp);
54 static void word(struct vars *v, int dir, struct state *lp, struct state *rp);
55 static void charclass(struct vars *v, enum char_classes cls, struct state *lp,
56  struct state *rp);
57 static void charclasscomplement(struct vars *v, enum char_classes cls,
58  struct state *lp, struct state *rp);
59 static int scannum(struct vars *v);
60 static void repeat(struct vars *v, struct state *lp, struct state *rp,
61  int m, int n);
62 static void bracket(struct vars *v, struct state *lp, struct state *rp);
63 static void cbracket(struct vars *v, struct state *lp, struct state *rp);
64 static void brackpart(struct vars *v, struct state *lp, struct state *rp,
65  bool *have_cclassc);
66 static const chr *scanplain(struct vars *v);
67 static void onechr(struct vars *v, chr c, struct state *lp, struct state *rp);
68 static void optimizebracket(struct vars *v, struct state *lp, struct state *rp);
69 static void wordchrs(struct vars *v);
70 static void processlacon(struct vars *v, struct state *begin,
71  struct state *end, int latype,
72  struct state *lp, struct state *rp);
73 static struct subre *subre(struct vars *v, int op, int flags,
74  struct state *begin, struct state *end);
75 static void freesubre(struct vars *v, struct subre *sr);
76 static void freesubreandsiblings(struct vars *v, struct subre *sr);
77 static void freesrnode(struct vars *v, struct subre *sr);
78 static void removecaptures(struct vars *v, struct subre *t);
79 static int numst(struct subre *t, int start);
80 static void markst(struct subre *t);
81 static void cleanst(struct vars *v);
82 static long nfatree(struct vars *v, struct subre *t, FILE *f);
83 static long nfanode(struct vars *v, struct subre *t,
84  int converttosearch, FILE *f);
85 static int newlacon(struct vars *v, struct state *begin, struct state *end,
86  int latype);
87 static void freelacons(struct subre *subs, int n);
88 static void rfree(regex_t *re);
89 static int rcancelrequested(void);
90 static int rstacktoodeep(void);
91 
92 #ifdef REG_DEBUG
93 static void dump(regex_t *re, FILE *f);
94 static void dumpst(struct subre *t, FILE *f, int nfapresent);
95 static void stdump(struct subre *t, FILE *f, int nfapresent);
96 static const char *stid(struct subre *t, char *buf, size_t bufsize);
97 #endif
98 /* === regc_lex.c === */
99 static void lexstart(struct vars *v);
100 static void prefixes(struct vars *v);
101 static int next(struct vars *v);
102 static int lexescape(struct vars *v);
103 static chr lexdigits(struct vars *v, int base, int minlen, int maxlen);
104 static int brenext(struct vars *v, chr c);
105 static void skip(struct vars *v);
106 static chr newline(void);
107 static chr chrnamed(struct vars *v, const chr *startp, const chr *endp,
108  chr lastresort);
109 
110 /* === regc_color.c === */
111 static void initcm(struct vars *v, struct colormap *cm);
112 static void freecm(struct colormap *cm);
113 static color maxcolor(struct colormap *cm);
114 static color newcolor(struct colormap *cm);
115 static void freecolor(struct colormap *cm, color co);
116 static color pseudocolor(struct colormap *cm);
117 static color subcolor(struct colormap *cm, chr c);
118 static color subcolorhi(struct colormap *cm, color *pco);
119 static color newsub(struct colormap *cm, color co);
120 static int newhicolorrow(struct colormap *cm, int oldrow);
121 static void newhicolorcols(struct colormap *cm);
122 static void subcolorcvec(struct vars *v, struct cvec *cv, struct state *lp,
123  struct state *rp);
124 static void subcoloronechr(struct vars *v, chr ch, struct state *lp,
125  struct state *rp, color *lastsubcolor);
126 static void subcoloronerange(struct vars *v, chr from, chr to,
127  struct state *lp, struct state *rp,
128  color *lastsubcolor);
129 static void subcoloronerow(struct vars *v, int rownum, struct state *lp,
130  struct state *rp, color *lastsubcolor);
131 static void okcolors(struct nfa *nfa, struct colormap *cm);
132 static void colorchain(struct colormap *cm, struct arc *a);
133 static void uncolorchain(struct colormap *cm, struct arc *a);
134 static void rainbow(struct nfa *nfa, struct colormap *cm, int type, color but,
135  struct state *from, struct state *to);
136 static void colorcomplement(struct nfa *nfa, struct colormap *cm, int type,
137  struct state *of, struct state *from,
138  struct state *to);
139 
140 #ifdef REG_DEBUG
141 static void dumpcolors(struct colormap *cm, FILE *f);
142 static void dumpchr(chr c, FILE *f);
143 #endif
144 /* === regc_nfa.c === */
145 static struct nfa *newnfa(struct vars *v, struct colormap *cm,
146  struct nfa *parent);
147 static void freenfa(struct nfa *nfa);
148 static struct state *newstate(struct nfa *nfa);
149 static struct state *newfstate(struct nfa *nfa, int flag);
150 static void dropstate(struct nfa *nfa, struct state *s);
151 static void freestate(struct nfa *nfa, struct state *s);
152 static void newarc(struct nfa *nfa, int t, color co,
153  struct state *from, struct state *to);
154 static void createarc(struct nfa *nfa, int t, color co,
155  struct state *from, struct state *to);
156 static struct arc *allocarc(struct nfa *nfa);
157 static void freearc(struct nfa *nfa, struct arc *victim);
158 static void changearcsource(struct arc *a, struct state *newfrom);
159 static void changearctarget(struct arc *a, struct state *newto);
160 static int hasnonemptyout(struct state *s);
161 static struct arc *findarc(struct state *s, int type, color co);
162 static void cparc(struct nfa *nfa, struct arc *oa,
163  struct state *from, struct state *to);
164 static void sortins(struct nfa *nfa, struct state *s);
165 static int sortins_cmp(const void *a, const void *b);
166 static void sortouts(struct nfa *nfa, struct state *s);
167 static int sortouts_cmp(const void *a, const void *b);
168 static void moveins(struct nfa *nfa, struct state *oldState,
169  struct state *newState);
170 static void copyins(struct nfa *nfa, struct state *oldState,
171  struct state *newState);
172 static void mergeins(struct nfa *nfa, struct state *s,
173  struct arc **arcarray, int arccount);
174 static void moveouts(struct nfa *nfa, struct state *oldState,
175  struct state *newState);
176 static void copyouts(struct nfa *nfa, struct state *oldState,
177  struct state *newState);
178 static void cloneouts(struct nfa *nfa, struct state *old, struct state *from,
179  struct state *to, int type);
180 static void delsub(struct nfa *nfa, struct state *lp, struct state *rp);
181 static void deltraverse(struct nfa *nfa, struct state *leftend,
182  struct state *s);
183 static void dupnfa(struct nfa *nfa, struct state *start, struct state *stop,
184  struct state *from, struct state *to);
185 static void duptraverse(struct nfa *nfa, struct state *s, struct state *stmp);
186 static void removeconstraints(struct nfa *nfa, struct state *start, struct state *stop);
187 static void removetraverse(struct nfa *nfa, struct state *s);
188 static void cleartraverse(struct nfa *nfa, struct state *s);
189 static struct state *single_color_transition(struct state *s1,
190  struct state *s2);
191 static void specialcolors(struct nfa *nfa);
192 static long optimize(struct nfa *nfa, FILE *f);
193 static void pullback(struct nfa *nfa, FILE *f);
194 static int pull(struct nfa *nfa, struct arc *con,
195  struct state **intermediates);
196 static void pushfwd(struct nfa *nfa, FILE *f);
197 static int push(struct nfa *nfa, struct arc *con,
198  struct state **intermediates);
199 
200 #define INCOMPATIBLE 1 /* destroys arc */
201 #define SATISFIED 2 /* constraint satisfied */
202 #define COMPATIBLE 3 /* compatible but not satisfied yet */
203 #define REPLACEARC 4 /* replace arc's color with constraint color */
204 static int combine(struct nfa *nfa, struct arc *con, struct arc *a);
205 static void fixempties(struct nfa *nfa, FILE *f);
206 static struct state *emptyreachable(struct nfa *nfa, struct state *s,
207  struct state *lastfound,
208  struct arc **inarcsorig);
209 static int isconstraintarc(struct arc *a);
210 static int hasconstraintout(struct state *s);
211 static void fixconstraintloops(struct nfa *nfa, FILE *f);
212 static int findconstraintloop(struct nfa *nfa, struct state *s);
213 static void breakconstraintloop(struct nfa *nfa, struct state *sinitial);
214 static void clonesuccessorstates(struct nfa *nfa, struct state *ssource,
215  struct state *sclone,
216  struct state *spredecessor,
217  struct arc *refarc, char *curdonemap,
218  char *outerdonemap, int nstates);
219 static void cleanup(struct nfa *nfa);
220 static void markreachable(struct nfa *nfa, struct state *s,
221  struct state *okay, struct state *mark);
222 static void markcanreach(struct nfa *nfa, struct state *s, struct state *okay,
223  struct state *mark);
224 static long analyze(struct nfa *nfa);
225 static void checkmatchall(struct nfa *nfa);
226 static bool checkmatchall_recurse(struct nfa *nfa, struct state *s,
227  bool **haspaths);
228 static bool check_out_colors_match(struct state *s, color co1, color co2);
229 static bool check_in_colors_match(struct state *s, color co1, color co2);
230 static void compact(struct nfa *nfa, struct cnfa *cnfa);
231 static void carcsort(struct carc *first, size_t n);
232 static int carc_cmp(const void *a, const void *b);
233 static void freecnfa(struct cnfa *cnfa);
234 static void dumpnfa(struct nfa *nfa, FILE *f);
235 
236 #ifdef REG_DEBUG
237 static void dumpstate(struct state *s, FILE *f);
238 static void dumparcs(struct state *s, FILE *f);
239 static void dumparc(struct arc *a, struct state *s, FILE *f);
240 static void dumpcnfa(struct cnfa *cnfa, FILE *f);
241 static void dumpcstate(int st, struct cnfa *cnfa, FILE *f);
242 #endif
243 /* === regc_cvec.c === */
244 static struct cvec *newcvec(int nchrs, int nranges);
245 static struct cvec *clearcvec(struct cvec *cv);
246 static void addchr(struct cvec *cv, chr c);
247 static void addrange(struct cvec *cv, chr from, chr to);
248 static struct cvec *getcvec(struct vars *v, int nchrs, int nranges);
249 static void freecvec(struct cvec *cv);
250 
251 /* === regc_pg_locale.c === */
255 static int pg_wc_isword(pg_wchar c);
264 
265 /* === regc_locale.c === */
266 static chr element(struct vars *v, const chr *startp, const chr *endp);
267 static struct cvec *range(struct vars *v, chr a, chr b, int cases);
268 static int before(chr x, chr y);
269 static struct cvec *eclass(struct vars *v, chr c, int cases);
270 static enum char_classes lookupcclass(struct vars *v, const chr *startp,
271  const chr *endp);
272 static struct cvec *cclasscvec(struct vars *v, enum char_classes cclasscode,
273  int cases);
274 static int cclass_column_index(struct colormap *cm, chr c);
275 static struct cvec *allcases(struct vars *v, chr c);
276 static int cmp(const chr *x, const chr *y, size_t len);
277 static int casecmp(const chr *x, const chr *y, size_t len);
278 
279 
280 /* internal variables, bundled for easy passing around */
281 struct vars
282 {
284  const chr *now; /* scan pointer into string */
285  const chr *stop; /* end of string */
286  int err; /* error code (0 if none) */
287  int cflags; /* copy of compile flags */
288  int lasttype; /* type of previous token */
289  int nexttype; /* type of next token */
290  chr nextvalue; /* value (if any) of next token */
291  int lexcon; /* lexical context type (see regc_lex.c) */
292  int nsubexp; /* subexpression count */
293  struct subre **subs; /* subRE pointer vector */
294  size_t nsubs; /* length of vector */
295  struct subre *sub10[10]; /* initial vector, enough for most */
296  struct nfa *nfa; /* the NFA */
297  struct colormap *cm; /* character color map */
298  color nlcolor; /* color of newline */
299  struct state *wordchrs; /* state in nfa holding word-char outarcs */
300  struct subre *tree; /* subexpression tree */
301  struct subre *treechain; /* all tree nodes allocated */
302  struct subre *treefree; /* any free tree nodes */
303  int ntree; /* number of tree nodes, plus one */
304  struct cvec *cv; /* interface cvec */
305  struct cvec *cv2; /* utility cvec */
306  struct subre *lacons; /* lookaround-constraint vector */
307  int nlacons; /* size of lacons[]; note that only slots
308  * numbered 1 .. nlacons-1 are used */
309  size_t spaceused; /* approx. space used for compilation */
310 };
311 
312 /* parsing macros; most know that `v' is the struct vars pointer */
313 #define NEXT() (next(v)) /* advance by one token */
314 #define SEE(t) (v->nexttype == (t)) /* is next token this? */
315 #define EAT(t) (SEE(t) && next(v)) /* if next is this, swallow it */
316 #define VISERR(vv) ((vv)->err != 0) /* have we seen an error yet? */
317 #define ISERR() VISERR(v)
318 #define VERR(vv,e) ((vv)->nexttype = EOS, \
319  (vv)->err = ((vv)->err ? (vv)->err : (e)))
320 #define ERR(e) VERR(v, e) /* record an error */
321 #define NOERR() {if (ISERR()) return;} /* if error seen, return */
322 #define NOERRN() {if (ISERR()) return NULL;} /* NOERR with retval */
323 #define NOERRZ() {if (ISERR()) return 0;} /* NOERR with retval */
324 #define INSIST(c, e) do { if (!(c)) ERR(e); } while (0) /* error if c false */
325 #define NOTE(b) (v->re->re_info |= (b)) /* note visible condition */
326 #define EMPTYARC(x, y) newarc(v->nfa, EMPTY, 0, x, y)
327 
328 /* token type codes, some also used as NFA arc types */
329 #define EMPTY 'n' /* no token present */
330 #define EOS 'e' /* end of string */
331 #define PLAIN 'p' /* ordinary character */
332 #define DIGIT 'd' /* digit (in bound) */
333 #define BACKREF 'b' /* back reference */
334 #define COLLEL 'I' /* start of [. */
335 #define ECLASS 'E' /* start of [= */
336 #define CCLASS 'C' /* start of [: */
337 #define END 'X' /* end of [. [= [: */
338 #define CCLASSS 's' /* char class shorthand escape */
339 #define CCLASSC 'c' /* complement char class shorthand escape */
340 #define RANGE 'R' /* - within [] which might be range delim. */
341 #define LACON 'L' /* lookaround constraint subRE */
342 #define AHEAD 'a' /* color-lookahead arc */
343 #define BEHIND 'r' /* color-lookbehind arc */
344 #define WBDRY 'w' /* word boundary constraint */
345 #define NWBDRY 'W' /* non-word-boundary constraint */
346 #define SBEGIN 'A' /* beginning of string (even if not BOL) */
347 #define SEND 'Z' /* end of string (even if not EOL) */
348 
349 /* is an arc colored, and hence should belong to a color chain? */
350 /* the test on "co" eliminates RAINBOW arcs, which we don't bother to chain */
351 #define COLORED(a) \
352  ((a)->co >= 0 && \
353  ((a)->type == PLAIN || (a)->type == AHEAD || (a)->type == BEHIND))
354 
355 
356 /* static function list */
357 static const struct fns functions = {
358  rfree, /* regfree insides */
359  rcancelrequested, /* check for cancel request */
360  rstacktoodeep /* check for stack getting dangerously deep */
361 };
362 
363 
364 
365 /*
366  * pg_regcomp - compile regular expression
367  *
368  * Note: on failure, no resources remain allocated, so pg_regfree()
369  * need not be applied to re.
370  */
371 int
373  const chr *string,
374  size_t len,
375  int flags,
376  Oid collation)
377 {
378  struct vars var;
379  struct vars *v = &var;
380  struct guts *g;
381  int i;
382  size_t j;
383 
384 #ifdef REG_DEBUG
385  FILE *debug = (flags & REG_PROGRESS) ? stdout : (FILE *) NULL;
386 #else
387  FILE *debug = (FILE *) NULL;
388 #endif
389 
390 #define CNOERR() { if (ISERR()) return freev(v, v->err); }
391 
392  /* sanity checks */
393 
394  if (re == NULL || string == NULL)
395  return REG_INVARG;
396  if ((flags & REG_QUOTE) &&
397  (flags & (REG_ADVANCED | REG_EXPANDED | REG_NEWLINE)))
398  return REG_INVARG;
399  if (!(flags & REG_EXTENDED) && (flags & REG_ADVF))
400  return REG_INVARG;
401 
402  /* Initialize locale-dependent support */
403  pg_set_regex_collation(collation);
404 
405  /* initial setup (after which freev() is callable) */
406  v->re = re;
407  v->now = string;
408  v->stop = v->now + len;
409  v->err = 0;
410  v->cflags = flags;
411  v->nsubexp = 0;
412  v->subs = v->sub10;
413  v->nsubs = 10;
414  for (j = 0; j < v->nsubs; j++)
415  v->subs[j] = NULL;
416  v->nfa = NULL;
417  v->cm = NULL;
418  v->nlcolor = COLORLESS;
419  v->wordchrs = NULL;
420  v->tree = NULL;
421  v->treechain = NULL;
422  v->treefree = NULL;
423  v->cv = NULL;
424  v->cv2 = NULL;
425  v->lacons = NULL;
426  v->nlacons = 0;
427  v->spaceused = 0;
428  re->re_magic = REMAGIC;
429  re->re_info = 0; /* bits get set during parse */
430  re->re_csize = sizeof(chr);
431  re->re_collation = collation;
432  re->re_guts = NULL;
433  re->re_fns = VS(&functions);
434 
435  /* more complex setup, malloced things */
436  re->re_guts = VS(MALLOC(sizeof(struct guts)));
437  if (re->re_guts == NULL)
438  return freev(v, REG_ESPACE);
439  g = (struct guts *) re->re_guts;
440  g->tree = NULL;
441  initcm(v, &g->cmap);
442  v->cm = &g->cmap;
443  g->lacons = NULL;
444  g->nlacons = 0;
445  ZAPCNFA(g->search);
446  v->nfa = newnfa(v, v->cm, (struct nfa *) NULL);
447  CNOERR();
448  /* set up a reasonably-sized transient cvec for getcvec usage */
449  v->cv = newcvec(100, 20);
450  if (v->cv == NULL)
451  return freev(v, REG_ESPACE);
452 
453  /* parsing */
454  lexstart(v); /* also handles prefixes */
455  if ((v->cflags & REG_NLSTOP) || (v->cflags & REG_NLANCH))
456  {
457  /* assign newline a unique color */
458  v->nlcolor = subcolor(v->cm, newline());
459  okcolors(v->nfa, v->cm);
460  }
461  CNOERR();
462  v->tree = parse(v, EOS, PLAIN, v->nfa->init, v->nfa->final);
463  assert(SEE(EOS)); /* even if error; ISERR() => SEE(EOS) */
464  CNOERR();
465  assert(v->tree != NULL);
466 
467  /* finish setup of nfa and its subre tree */
468  specialcolors(v->nfa);
469  CNOERR();
470 #ifdef REG_DEBUG
471  if (debug != NULL)
472  {
473  fprintf(debug, "\n\n\n========= RAW ==========\n");
474  dumpnfa(v->nfa, debug);
475  dumpst(v->tree, debug, 1);
476  }
477 #endif
478  if (v->cflags & REG_NOSUB)
479  removecaptures(v, v->tree);
480  v->ntree = numst(v->tree, 1);
481  markst(v->tree);
482  cleanst(v);
483 #ifdef REG_DEBUG
484  if (debug != NULL)
485  {
486  fprintf(debug, "\n\n\n========= TREE FIXED ==========\n");
487  dumpst(v->tree, debug, 1);
488  }
489 #endif
490 
491  /* build compacted NFAs for tree and lacons */
492  re->re_info |= nfatree(v, v->tree, debug);
493  CNOERR();
494  assert(v->nlacons == 0 || v->lacons != NULL);
495  for (i = 1; i < v->nlacons; i++)
496  {
497  struct subre *lasub = &v->lacons[i];
498 
499 #ifdef REG_DEBUG
500  if (debug != NULL)
501  fprintf(debug, "\n\n\n========= LA%d ==========\n", i);
502 #endif
503 
504  /* Prepend .* to pattern if it's a lookbehind LACON */
505  nfanode(v, lasub, !LATYPE_IS_AHEAD(lasub->latype), debug);
506  }
507  CNOERR();
508  if (v->tree->flags & SHORTER)
510 
511  /* build compacted NFAs for tree, lacons, fast search */
512 #ifdef REG_DEBUG
513  if (debug != NULL)
514  fprintf(debug, "\n\n\n========= SEARCH ==========\n");
515 #endif
516  /* can sacrifice main NFA now, so use it as work area */
517  (DISCARD) optimize(v->nfa, debug);
518  CNOERR();
519  makesearch(v, v->nfa);
520  CNOERR();
521  compact(v->nfa, &g->search);
522  CNOERR();
523 
524  /* looks okay, package it up */
525  re->re_nsub = v->nsubexp;
526  v->re = NULL; /* freev no longer frees re */
527  g->magic = GUTSMAGIC;
528  g->cflags = v->cflags;
529  g->info = re->re_info;
530  g->nsub = re->re_nsub;
531  g->tree = v->tree;
532  v->tree = NULL;
533  g->ntree = v->ntree;
534  g->compare = (v->cflags & REG_ICASE) ? casecmp : cmp;
535  g->lacons = v->lacons;
536  v->lacons = NULL;
537  g->nlacons = v->nlacons;
538 
539 #ifdef REG_DEBUG
540  if (flags & REG_DUMP)
541  {
542  dump(re, stdout);
543  fflush(stdout);
544  }
545 #endif
546 
547  assert(v->err == 0);
548  return freev(v, 0);
549 }
550 
551 /*
552  * moresubs - enlarge subRE vector
553  */
554 static void
555 moresubs(struct vars *v,
556  int wanted) /* want enough room for this one */
557 {
558  struct subre **p;
559  size_t n;
560 
561  assert(wanted > 0 && (size_t) wanted >= v->nsubs);
562  n = (size_t) wanted * 3 / 2 + 1;
563 
564  if (v->subs == v->sub10)
565  {
566  p = (struct subre **) MALLOC(n * sizeof(struct subre *));
567  if (p != NULL)
568  memcpy(VS(p), VS(v->subs),
569  v->nsubs * sizeof(struct subre *));
570  }
571  else
572  p = (struct subre **) REALLOC(v->subs, n * sizeof(struct subre *));
573  if (p == NULL)
574  {
575  ERR(REG_ESPACE);
576  return;
577  }
578  v->subs = p;
579  for (p = &v->subs[v->nsubs]; v->nsubs < n; p++, v->nsubs++)
580  *p = NULL;
581  assert(v->nsubs == n);
582  assert((size_t) wanted < v->nsubs);
583 }
584 
585 /*
586  * freev - free vars struct's substructures where necessary
587  *
588  * Optionally does error-number setting, and always returns error code
589  * (if any), to make error-handling code terser.
590  */
591 static int
592 freev(struct vars *v,
593  int err)
594 {
595  if (v->re != NULL)
596  rfree(v->re);
597  if (v->subs != v->sub10)
598  FREE(v->subs);
599  if (v->nfa != NULL)
600  freenfa(v->nfa);
601  if (v->tree != NULL)
602  freesubre(v, v->tree);
603  if (v->treechain != NULL)
604  cleanst(v);
605  if (v->cv != NULL)
606  freecvec(v->cv);
607  if (v->cv2 != NULL)
608  freecvec(v->cv2);
609  if (v->lacons != NULL)
610  freelacons(v->lacons, v->nlacons);
611  ERR(err); /* nop if err==0 */
612 
613  return v->err;
614 }
615 
616 /*
617  * makesearch - turn an NFA into a search NFA (implicit prepend of .*?)
618  * NFA must have been optimize()d already.
619  */
620 static void
621 makesearch(struct vars *v,
622  struct nfa *nfa)
623 {
624  struct arc *a;
625  struct arc *b;
626  struct state *pre = nfa->pre;
627  struct state *s;
628  struct state *s2;
629  struct state *slist;
630 
631  /* no loops are needed if it's anchored */
632  for (a = pre->outs; a != NULL; a = a->outchain)
633  {
634  assert(a->type == PLAIN);
635  if (a->co != nfa->bos[0] && a->co != nfa->bos[1])
636  break;
637  }
638  if (a != NULL)
639  {
640  /* add implicit .* in front */
641  rainbow(nfa, v->cm, PLAIN, COLORLESS, pre, pre);
642 
643  /* and ^* and \A* too -- not always necessary, but harmless */
644  newarc(nfa, PLAIN, nfa->bos[0], pre, pre);
645  newarc(nfa, PLAIN, nfa->bos[1], pre, pre);
646 
647  /*
648  * The pattern is still MATCHALL if it was before, but the max match
649  * length is now infinity.
650  */
651  if (nfa->flags & MATCHALL)
653  }
654 
655  /*
656  * Now here's the subtle part. Because many REs have no lookback
657  * constraints, often knowing when you were in the pre state tells you
658  * little; it's the next state(s) that are informative. But some of them
659  * may have other inarcs, i.e. it may be possible to make actual progress
660  * and then return to one of them. We must de-optimize such cases,
661  * splitting each such state into progress and no-progress states.
662  */
663 
664  /* first, make a list of the states reachable from pre and elsewhere */
665  slist = NULL;
666  for (a = pre->outs; a != NULL; a = a->outchain)
667  {
668  s = a->to;
669  for (b = s->ins; b != NULL; b = b->inchain)
670  {
671  if (b->from != pre)
672  break;
673  }
674 
675  /*
676  * We want to mark states as being in the list already by having non
677  * NULL tmp fields, but we can't just store the old slist value in tmp
678  * because that doesn't work for the first such state. Instead, the
679  * first list entry gets its own address in tmp.
680  */
681  if (b != NULL && s->tmp == NULL)
682  {
683  s->tmp = (slist != NULL) ? slist : s;
684  slist = s;
685  }
686  }
687 
688  /* do the splits */
689  for (s = slist; s != NULL; s = s2)
690  {
691  s2 = newstate(nfa);
692  NOERR();
693  copyouts(nfa, s, s2);
694  NOERR();
695  for (a = s->ins; a != NULL; a = b)
696  {
697  b = a->inchain;
698  if (a->from != pre)
699  {
700  cparc(nfa, a, a->from, s2);
701  freearc(nfa, a);
702  }
703  }
704  s2 = (s->tmp != s) ? s->tmp : NULL;
705  s->tmp = NULL; /* clean up while we're at it */
706  }
707 }
708 
709 /*
710  * parse - parse an RE
711  *
712  * This is actually just the top level, which parses a bunch of branches
713  * tied together with '|'. If there's more than one, they appear in the
714  * tree as the children of a '|' subre.
715  */
716 static struct subre *
717 parse(struct vars *v,
718  int stopper, /* EOS or ')' */
719  int type, /* LACON (lookaround subRE) or PLAIN */
720  struct state *init, /* initial state */
721  struct state *final) /* final state */
722 {
723  struct subre *branches; /* top level */
724  struct subre *lastbranch; /* latest branch */
725 
726  assert(stopper == ')' || stopper == EOS);
727 
728  branches = subre(v, '|', LONGER, init, final);
729  NOERRN();
730  lastbranch = NULL;
731  do
732  { /* a branch */
733  struct subre *branch;
734  struct state *left; /* scaffolding for branch */
735  struct state *right;
736 
737  left = newstate(v->nfa);
738  right = newstate(v->nfa);
739  NOERRN();
740  EMPTYARC(init, left);
741  EMPTYARC(right, final);
742  NOERRN();
743  branch = parsebranch(v, stopper, type, left, right, 0);
744  NOERRN();
745  if (lastbranch)
746  lastbranch->sibling = branch;
747  else
748  branches->child = branch;
749  branches->flags |= UP(branches->flags | branch->flags);
750  lastbranch = branch;
751  } while (EAT('|'));
752  assert(SEE(stopper) || SEE(EOS));
753 
754  if (!SEE(stopper))
755  {
756  assert(stopper == ')' && SEE(EOS));
757  ERR(REG_EPAREN);
758  }
759 
760  /* optimize out simple cases */
761  if (lastbranch == branches->child)
762  { /* only one branch */
763  assert(lastbranch->sibling == NULL);
764  freesrnode(v, branches);
765  branches = lastbranch;
766  }
767  else if (!MESSY(branches->flags))
768  { /* no interesting innards */
769  freesubreandsiblings(v, branches->child);
770  branches->child = NULL;
771  branches->op = '=';
772  }
773 
774  return branches;
775 }
776 
777 /*
778  * parsebranch - parse one branch of an RE
779  *
780  * This mostly manages concatenation, working closely with parseqatom().
781  * Concatenated things are bundled up as much as possible, with separate
782  * '.' nodes introduced only when necessary due to substructure.
783  */
784 static struct subre *
785 parsebranch(struct vars *v,
786  int stopper, /* EOS or ')' */
787  int type, /* LACON (lookaround subRE) or PLAIN */
788  struct state *left, /* leftmost state */
789  struct state *right, /* rightmost state */
790  int partial) /* is this only part of a branch? */
791 {
792  struct state *lp; /* left end of current construct */
793  int seencontent; /* is there anything in this branch yet? */
794  struct subre *t;
795 
796  lp = left;
797  seencontent = 0;
798  t = subre(v, '=', 0, left, right); /* op '=' is tentative */
799  NOERRN();
800  while (!SEE('|') && !SEE(stopper) && !SEE(EOS))
801  {
802  if (seencontent)
803  { /* implicit concat operator */
804  lp = newstate(v->nfa);
805  NOERRN();
806  moveins(v->nfa, right, lp);
807  }
808  seencontent = 1;
809 
810  /* NB, recursion in parseqatom() may swallow rest of branch */
811  t = parseqatom(v, stopper, type, lp, right, t);
812  NOERRN();
813  }
814 
815  if (!seencontent)
816  { /* empty branch */
817  if (!partial)
818  NOTE(REG_UUNSPEC);
819  assert(lp == left);
820  EMPTYARC(left, right);
821  }
822 
823  return t;
824 }
825 
826 /*
827  * parseqatom - parse one quantified atom or constraint of an RE
828  *
829  * The bookkeeping near the end cooperates very closely with parsebranch();
830  * in particular, it contains a recursion that can involve parsing the rest
831  * of the branch, making this function's name somewhat inaccurate.
832  *
833  * Usually, the return value is just "top", but in some cases where we
834  * have parsed the rest of the branch, we may deem "top" redundant and
835  * free it, returning some child subre instead.
836  */
837 static struct subre *
838 parseqatom(struct vars *v,
839  int stopper, /* EOS or ')' */
840  int type, /* LACON (lookaround subRE) or PLAIN */
841  struct state *lp, /* left state to hang it on */
842  struct state *rp, /* right state to hang it on */
843  struct subre *top) /* subtree top */
844 {
845  struct state *s; /* temporaries for new states */
846  struct state *s2;
847 
848 #define ARCV(t, val) newarc(v->nfa, t, val, lp, rp)
849  int m,
850  n;
851  struct subre *atom; /* atom's subtree */
852  struct subre *t;
853  int cap; /* capturing parens? */
854  int latype; /* lookaround constraint type */
855  int subno; /* capturing-parens or backref number */
856  int atomtype;
857  int qprefer; /* quantifier short/long preference */
858  int f;
859  struct subre **atomp; /* where the pointer to atom is */
860 
861  /* initial bookkeeping */
862  atom = NULL;
863  assert(lp->nouts == 0); /* must string new code */
864  assert(rp->nins == 0); /* between lp and rp */
865  subno = 0; /* just to shut lint up */
866 
867  /* an atom or constraint... */
868  atomtype = v->nexttype;
869  switch (atomtype)
870  {
871  /* first, constraints, which end by returning */
872  case '^':
873  ARCV('^', 1);
874  if (v->cflags & REG_NLANCH)
875  ARCV(BEHIND, v->nlcolor);
876  NEXT();
877  return top;
878  break;
879  case '$':
880  ARCV('$', 1);
881  if (v->cflags & REG_NLANCH)
882  ARCV(AHEAD, v->nlcolor);
883  NEXT();
884  return top;
885  break;
886  case SBEGIN:
887  ARCV('^', 1); /* BOL */
888  ARCV('^', 0); /* or BOS */
889  NEXT();
890  return top;
891  break;
892  case SEND:
893  ARCV('$', 1); /* EOL */
894  ARCV('$', 0); /* or EOS */
895  NEXT();
896  return top;
897  break;
898  case '<':
899  wordchrs(v);
900  s = newstate(v->nfa);
901  NOERRN();
902  nonword(v, BEHIND, lp, s);
903  word(v, AHEAD, s, rp);
904  NEXT();
905  return top;
906  break;
907  case '>':
908  wordchrs(v);
909  s = newstate(v->nfa);
910  NOERRN();
911  word(v, BEHIND, lp, s);
912  nonword(v, AHEAD, s, rp);
913  NEXT();
914  return top;
915  break;
916  case WBDRY:
917  wordchrs(v);
918  s = newstate(v->nfa);
919  NOERRN();
920  nonword(v, BEHIND, lp, s);
921  word(v, AHEAD, s, rp);
922  s = newstate(v->nfa);
923  NOERRN();
924  word(v, BEHIND, lp, s);
925  nonword(v, AHEAD, s, rp);
926  NEXT();
927  return top;
928  break;
929  case NWBDRY:
930  wordchrs(v);
931  s = newstate(v->nfa);
932  NOERRN();
933  word(v, BEHIND, lp, s);
934  word(v, AHEAD, s, rp);
935  s = newstate(v->nfa);
936  NOERRN();
937  nonword(v, BEHIND, lp, s);
938  nonword(v, AHEAD, s, rp);
939  NEXT();
940  return top;
941  break;
942  case LACON: /* lookaround constraint */
943  latype = v->nextvalue;
944  NEXT();
945  s = newstate(v->nfa);
946  s2 = newstate(v->nfa);
947  NOERRN();
948  t = parse(v, ')', LACON, s, s2);
949  freesubre(v, t); /* internal structure irrelevant */
950  NOERRN();
951  assert(SEE(')'));
952  NEXT();
953  processlacon(v, s, s2, latype, lp, rp);
954  return top;
955  break;
956  /* then errors, to get them out of the way */
957  case '*':
958  case '+':
959  case '?':
960  case '{':
961  ERR(REG_BADRPT);
962  return top;
963  break;
964  default:
965  ERR(REG_ASSERT);
966  return top;
967  break;
968  /* then plain characters, and minor variants on that theme */
969  case ')': /* unbalanced paren */
970  if ((v->cflags & REG_ADVANCED) != REG_EXTENDED)
971  {
972  ERR(REG_EPAREN);
973  return top;
974  }
975  /* legal in EREs due to specification botch */
976  NOTE(REG_UPBOTCH);
977  /* fall through into case PLAIN */
978  /* FALLTHROUGH */
979  case PLAIN:
980  onechr(v, v->nextvalue, lp, rp);
981  okcolors(v->nfa, v->cm);
982  NOERRN();
983  NEXT();
984  break;
985  case '[':
986  if (v->nextvalue == 1)
987  bracket(v, lp, rp);
988  else
989  cbracket(v, lp, rp);
990  assert(SEE(']') || ISERR());
991  NEXT();
992  break;
993  case CCLASSS:
994  charclass(v, (enum char_classes) v->nextvalue, lp, rp);
995  okcolors(v->nfa, v->cm);
996  NEXT();
997  break;
998  case CCLASSC:
999  charclasscomplement(v, (enum char_classes) v->nextvalue, lp, rp);
1000  /* charclasscomplement() did okcolors() internally */
1001  NEXT();
1002  break;
1003  case '.':
1004  rainbow(v->nfa, v->cm, PLAIN,
1005  (v->cflags & REG_NLSTOP) ? v->nlcolor : COLORLESS,
1006  lp, rp);
1007  NEXT();
1008  break;
1009  /* and finally the ugly stuff */
1010  case '(': /* value flags as capturing or non */
1011  cap = (type == LACON) ? 0 : v->nextvalue;
1012  if (cap)
1013  {
1014  v->nsubexp++;
1015  subno = v->nsubexp;
1016  if ((size_t) subno >= v->nsubs)
1017  moresubs(v, subno);
1018  }
1019  else
1020  atomtype = PLAIN; /* something that's not '(' */
1021  NEXT();
1022 
1023  /*
1024  * Make separate endpoint states to keep this sub-NFA distinct
1025  * from what surrounds it. We need to be sure that when we
1026  * duplicate the sub-NFA for a backref, we get the right
1027  * states/arcs and no others. In particular, letting a backref
1028  * duplicate the sub-NFA from lp to rp would be quite wrong,
1029  * because we may add quantification superstructure around this
1030  * atom below. (Perhaps we could skip the extra states for
1031  * non-capturing parens, but it seems not worth the trouble.)
1032  */
1033  s = newstate(v->nfa);
1034  s2 = newstate(v->nfa);
1035  NOERRN();
1036  /* We may not need these arcs, but keep things connected for now */
1037  EMPTYARC(lp, s);
1038  EMPTYARC(s2, rp);
1039  NOERRN();
1040  atom = parse(v, ')', type, s, s2);
1041  assert(SEE(')') || ISERR());
1042  NEXT();
1043  NOERRN();
1044  if (cap)
1045  {
1046  if (atom->capno == 0)
1047  {
1048  /* normal case: just mark the atom as capturing */
1049  atom->flags |= CAP;
1050  atom->capno = subno;
1051  }
1052  else
1053  {
1054  /* generate no-op wrapper node to handle "((x))" */
1055  t = subre(v, '(', atom->flags | CAP, s, s2);
1056  NOERRN();
1057  t->capno = subno;
1058  t->child = atom;
1059  atom = t;
1060  }
1061  assert(v->subs[subno] == NULL);
1062  v->subs[subno] = atom;
1063  }
1064  /* postpone everything else pending possible {0} */
1065  break;
1066  case BACKREF: /* the Feature From The Black Lagoon */
1068  subno = v->nextvalue;
1069  assert(subno > 0);
1070  INSIST(subno < v->nsubs, REG_ESUBREG);
1071  NOERRN();
1072  INSIST(v->subs[subno] != NULL, REG_ESUBREG);
1073  NOERRN();
1074  atom = subre(v, 'b', BACKR, lp, rp);
1075  NOERRN();
1076  atom->backno = subno;
1077  v->subs[subno]->flags |= BRUSE;
1078  EMPTYARC(lp, rp); /* temporarily, so there's something */
1079  NEXT();
1080  break;
1081  }
1082 
1083  /* ...and an atom may be followed by a quantifier */
1084  switch (v->nexttype)
1085  {
1086  case '*':
1087  m = 0;
1088  n = DUPINF;
1089  qprefer = (v->nextvalue) ? LONGER : SHORTER;
1090  NEXT();
1091  break;
1092  case '+':
1093  m = 1;
1094  n = DUPINF;
1095  qprefer = (v->nextvalue) ? LONGER : SHORTER;
1096  NEXT();
1097  break;
1098  case '?':
1099  m = 0;
1100  n = 1;
1101  qprefer = (v->nextvalue) ? LONGER : SHORTER;
1102  NEXT();
1103  break;
1104  case '{':
1105  NEXT();
1106  m = scannum(v);
1107  if (EAT(','))
1108  {
1109  if (SEE(DIGIT))
1110  n = scannum(v);
1111  else
1112  n = DUPINF;
1113  if (m > n)
1114  {
1115  ERR(REG_BADBR);
1116  return top;
1117  }
1118  /* {m,n} exercises preference, even if it's {m,m} */
1119  qprefer = (v->nextvalue) ? LONGER : SHORTER;
1120  }
1121  else
1122  {
1123  n = m;
1124  /* {m} passes operand's preference through */
1125  qprefer = 0;
1126  }
1127  if (!SEE('}'))
1128  { /* catches errors too */
1129  ERR(REG_BADBR);
1130  return top;
1131  }
1132  NEXT();
1133  break;
1134  default: /* no quantifier */
1135  m = n = 1;
1136  qprefer = 0;
1137  break;
1138  }
1139 
1140  /* annoying special case: {0} or {0,0} cancels everything */
1141  if (m == 0 && n == 0)
1142  {
1143  /*
1144  * If we had capturing subexpression(s) within the atom, we don't want
1145  * to destroy them, because it's legal (if useless) to back-ref them
1146  * later. Hence, just unlink the atom from lp/rp and then ignore it.
1147  */
1148  if (atom != NULL && (atom->flags & CAP))
1149  {
1150  delsub(v->nfa, lp, atom->begin);
1151  delsub(v->nfa, atom->end, rp);
1152  }
1153  else
1154  {
1155  /* Otherwise, we can clean up any subre infrastructure we made */
1156  if (atom != NULL)
1157  freesubre(v, atom);
1158  delsub(v->nfa, lp, rp);
1159  }
1160  EMPTYARC(lp, rp);
1161  return top;
1162  }
1163 
1164  /* if not a messy case, avoid hard part */
1165  assert(!MESSY(top->flags));
1166  f = top->flags | qprefer | ((atom != NULL) ? atom->flags : 0);
1167  if (atomtype != '(' && atomtype != BACKREF && !MESSY(UP(f)))
1168  {
1169  if (!(m == 1 && n == 1))
1170  repeat(v, lp, rp, m, n);
1171  if (atom != NULL)
1172  freesubre(v, atom);
1173  top->flags = f;
1174  return top;
1175  }
1176 
1177  /*
1178  * hard part: something messy
1179  *
1180  * That is, capturing parens, back reference, short/long clash, or an atom
1181  * with substructure containing one of those.
1182  */
1183 
1184  /* now we'll need a subre for the contents even if they're boring */
1185  if (atom == NULL)
1186  {
1187  atom = subre(v, '=', 0, lp, rp);
1188  NOERRN();
1189  }
1190 
1191  /*
1192  * For what follows, we need the atom to have its own begin/end states
1193  * that are distinct from lp/rp, so that we can wrap iteration structure
1194  * around it. The parenthesized-atom case above already made suitable
1195  * states (and we don't want to modify a capturing subre, since it's
1196  * already recorded in v->subs[]). Otherwise, we need more states.
1197  */
1198  if (atom->begin == lp || atom->end == rp)
1199  {
1200  s = newstate(v->nfa);
1201  s2 = newstate(v->nfa);
1202  NOERRN();
1203  moveouts(v->nfa, lp, s);
1204  moveins(v->nfa, rp, s2);
1205  atom->begin = s;
1206  atom->end = s2;
1207  }
1208  else
1209  {
1210  /* The atom's OK, but we must temporarily disconnect it from lp/rp */
1211  /* (this removes the EMPTY arcs we made above) */
1212  delsub(v->nfa, lp, atom->begin);
1213  delsub(v->nfa, atom->end, rp);
1214  }
1215 
1216  /*----------
1217  * Prepare a general-purpose state skeleton.
1218  *
1219  * In the no-backrefs case, we want this:
1220  *
1221  * [lp] ---> [s] ---prefix---> ---atom---> ---rest---> [rp]
1222  *
1223  * where prefix is some repetitions of atom, and "rest" is the remainder
1224  * of the branch. In the general case we need:
1225  *
1226  * [lp] ---> [s] ---iterator---> [s2] ---rest---> [rp]
1227  *
1228  * where the iterator wraps around the atom.
1229  *
1230  * We make the s state here for both cases; s2 is made below if needed
1231  *----------
1232  */
1233  s = newstate(v->nfa); /* set up starting state */
1234  NOERRN();
1235  EMPTYARC(lp, s);
1236  NOERRN();
1237 
1238  /* break remaining subRE into x{...} and what follows */
1239  t = subre(v, '.', COMBINE(qprefer, atom->flags), lp, rp);
1240  NOERRN();
1241  t->child = atom;
1242  atomp = &t->child;
1243 
1244  /*
1245  * Here we should recurse to fill t->child->sibling ... but we must
1246  * postpone that to the end. One reason is that t->child may be replaced
1247  * below, and we don't want to worry about its sibling link.
1248  */
1249 
1250  /*
1251  * Convert top node to a concatenation of the prefix (top->child, covering
1252  * whatever we parsed previously) and remaining (t). Note that the prefix
1253  * could be empty, in which case this concatenation node is unnecessary.
1254  * To keep things simple, we operate in a general way for now, and get rid
1255  * of unnecessary subres below.
1256  */
1257  assert(top->op == '=' && top->child == NULL);
1258  top->child = subre(v, '=', top->flags, top->begin, lp);
1259  NOERRN();
1260  top->op = '.';
1261  top->child->sibling = t;
1262  /* top->flags will get updated later */
1263 
1264  /* if it's a backref, now is the time to replicate the subNFA */
1265  if (atomtype == BACKREF)
1266  {
1267  assert(atom->begin->nouts == 1); /* just the EMPTY */
1268  delsub(v->nfa, atom->begin, atom->end);
1269  assert(v->subs[subno] != NULL);
1270 
1271  /*
1272  * And here's why the recursion got postponed: it must wait until the
1273  * skeleton is filled in, because it may hit a backref that wants to
1274  * copy the filled-in skeleton.
1275  */
1276  dupnfa(v->nfa, v->subs[subno]->begin, v->subs[subno]->end,
1277  atom->begin, atom->end);
1278  NOERRN();
1279 
1280  /* The backref node's NFA should not enforce any constraints */
1281  removeconstraints(v->nfa, atom->begin, atom->end);
1282  NOERRN();
1283  }
1284 
1285  /*
1286  * It's quantifier time. If the atom is just a backref, we'll let it deal
1287  * with quantifiers internally.
1288  */
1289  if (atomtype == BACKREF)
1290  {
1291  /* special case: backrefs have internal quantifiers */
1292  EMPTYARC(s, atom->begin); /* empty prefix */
1293  /* just stuff everything into atom */
1294  repeat(v, atom->begin, atom->end, m, n);
1295  atom->min = (short) m;
1296  atom->max = (short) n;
1297  atom->flags |= COMBINE(qprefer, atom->flags);
1298  /* rest of branch can be strung starting from atom->end */
1299  s2 = atom->end;
1300  }
1301  else if (m == 1 && n == 1 &&
1302  (qprefer == 0 ||
1303  (atom->flags & (LONGER | SHORTER | MIXED)) == 0 ||
1304  qprefer == (atom->flags & (LONGER | SHORTER | MIXED))))
1305  {
1306  /* no/vacuous quantifier: done */
1307  EMPTYARC(s, atom->begin); /* empty prefix */
1308  /* rest of branch can be strung starting from atom->end */
1309  s2 = atom->end;
1310  }
1311  else if (!(atom->flags & (CAP | BACKR)))
1312  {
1313  /*
1314  * If there's no captures nor backrefs in the atom being repeated, we
1315  * don't really care where the submatches of the iteration are, so we
1316  * don't need an iteration node. Make a plain DFA node instead.
1317  */
1318  EMPTYARC(s, atom->begin); /* empty prefix */
1319  repeat(v, atom->begin, atom->end, m, n);
1320  f = COMBINE(qprefer, atom->flags);
1321  t = subre(v, '=', f, atom->begin, atom->end);
1322  NOERRN();
1323  freesubre(v, atom);
1324  *atomp = t;
1325  /* rest of branch can be strung starting from t->end */
1326  s2 = t->end;
1327  }
1328  else if (m > 0 && !(atom->flags & BACKR))
1329  {
1330  /*
1331  * If there's no backrefs involved, we can turn x{m,n} into
1332  * x{m-1,n-1}x, with capturing parens in only the second x. This is
1333  * valid because we only care about capturing matches from the final
1334  * iteration of the quantifier. It's a win because we can implement
1335  * the backref-free left side as a plain DFA node, since we don't
1336  * really care where its submatches are.
1337  */
1338  dupnfa(v->nfa, atom->begin, atom->end, s, atom->begin);
1339  assert(m >= 1 && m != DUPINF && n >= 1);
1340  repeat(v, s, atom->begin, m - 1, (n == DUPINF) ? n : n - 1);
1341  f = COMBINE(qprefer, atom->flags);
1342  t = subre(v, '.', f, s, atom->end); /* prefix and atom */
1343  NOERRN();
1344  t->child = subre(v, '=', PREF(f), s, atom->begin);
1345  NOERRN();
1346  t->child->sibling = atom;
1347  *atomp = t;
1348  /* rest of branch can be strung starting from atom->end */
1349  s2 = atom->end;
1350  }
1351  else
1352  {
1353  /* general case: need an iteration node */
1354  s2 = newstate(v->nfa);
1355  NOERRN();
1356  moveouts(v->nfa, atom->end, s2);
1357  NOERRN();
1358  dupnfa(v->nfa, atom->begin, atom->end, s, s2);
1359  repeat(v, s, s2, m, n);
1360  f = COMBINE(qprefer, atom->flags);
1361  t = subre(v, '*', f, s, s2);
1362  NOERRN();
1363  t->min = (short) m;
1364  t->max = (short) n;
1365  t->child = atom;
1366  *atomp = t;
1367  /* rest of branch is to be strung from iteration's end state */
1368  }
1369 
1370  /* and finally, look after that postponed recursion */
1371  t = top->child->sibling;
1372  if (!(SEE('|') || SEE(stopper) || SEE(EOS)))
1373  {
1374  /* parse all the rest of the branch, and insert in t->child->sibling */
1375  t->child->sibling = parsebranch(v, stopper, type, s2, rp, 1);
1376  NOERRN();
1377  assert(SEE('|') || SEE(stopper) || SEE(EOS));
1378 
1379  /* here's the promised update of the flags */
1380  t->flags |= COMBINE(t->flags, t->child->sibling->flags);
1381  top->flags |= COMBINE(top->flags, t->flags);
1382 
1383  /* neither t nor top could be directly marked for capture as yet */
1384  assert(t->capno == 0);
1385  assert(top->capno == 0);
1386 
1387  /*
1388  * At this point both top and t are concatenation (op == '.') subres,
1389  * and we have top->child = prefix of branch, top->child->sibling = t,
1390  * t->child = messy atom (with quantification superstructure if
1391  * needed), t->child->sibling = rest of branch.
1392  *
1393  * If the messy atom was the first thing in the branch, then
1394  * top->child is vacuous and we can get rid of one level of
1395  * concatenation.
1396  */
1397  assert(top->child->op == '=');
1398  if (top->child->begin == top->child->end)
1399  {
1400  assert(!MESSY(top->child->flags));
1401  freesubre(v, top->child);
1402  top->child = t->child;
1403  freesrnode(v, t);
1404  }
1405 
1406  /*
1407  * Otherwise, it's possible that t->child is not messy in itself, but
1408  * we considered it messy because its greediness conflicts with what
1409  * preceded it. Then it could be that the combination of t->child and
1410  * the rest of the branch is also not messy, in which case we can get
1411  * rid of the child concatenation by merging t->child and the rest of
1412  * the branch into one plain DFA node.
1413  */
1414  else if (t->child->op == '=' &&
1415  t->child->sibling->op == '=' &&
1416  !MESSY(UP(t->child->flags | t->child->sibling->flags)))
1417  {
1418  t->op = '=';
1419  t->flags = COMBINE(t->child->flags, t->child->sibling->flags);
1420  freesubreandsiblings(v, t->child);
1421  t->child = NULL;
1422  }
1423  }
1424  else
1425  {
1426  /*
1427  * There's nothing left in the branch, so we don't need the second
1428  * concatenation node 't'. Just link s2 straight to rp.
1429  */
1430  EMPTYARC(s2, rp);
1431  top->child->sibling = t->child;
1432  top->flags |= COMBINE(top->flags, top->child->sibling->flags);
1433  freesrnode(v, t);
1434 
1435  /*
1436  * Again, it could be that top->child is vacuous (if the messy atom
1437  * was in fact the only thing in the branch). In that case we need no
1438  * concatenation at all; just replace top with top->child->sibling.
1439  */
1440  assert(top->child->op == '=');
1441  if (top->child->begin == top->child->end)
1442  {
1443  assert(!MESSY(top->child->flags));
1444  t = top->child->sibling;
1445  top->child->sibling = NULL;
1446  freesubre(v, top);
1447  top = t;
1448  }
1449  }
1450 
1451  return top;
1452 }
1453 
1454 /*
1455  * nonword - generate arcs for non-word-character ahead or behind
1456  */
1457 static void
1458 nonword(struct vars *v,
1459  int dir, /* AHEAD or BEHIND */
1460  struct state *lp,
1461  struct state *rp)
1462 {
1463  int anchor = (dir == AHEAD) ? '$' : '^';
1464 
1465  assert(dir == AHEAD || dir == BEHIND);
1466  newarc(v->nfa, anchor, 1, lp, rp);
1467  newarc(v->nfa, anchor, 0, lp, rp);
1468  colorcomplement(v->nfa, v->cm, dir, v->wordchrs, lp, rp);
1469  /* (no need for special attention to \n) */
1470 }
1471 
1472 /*
1473  * word - generate arcs for word character ahead or behind
1474  */
1475 static void
1476 word(struct vars *v,
1477  int dir, /* AHEAD or BEHIND */
1478  struct state *lp,
1479  struct state *rp)
1480 {
1481  assert(dir == AHEAD || dir == BEHIND);
1482  cloneouts(v->nfa, v->wordchrs, lp, rp, dir);
1483  /* (no need for special attention to \n) */
1484 }
1485 
1486 /*
1487  * charclass - generate arcs for a character class
1488  *
1489  * This is used for both atoms (\w and sibling escapes) and for elements
1490  * of bracket expressions. The caller is responsible for calling okcolors()
1491  * at the end of processing the atom or bracket.
1492  */
1493 static void
1494 charclass(struct vars *v,
1495  enum char_classes cls,
1496  struct state *lp,
1497  struct state *rp)
1498 {
1499  struct cvec *cv;
1500 
1501  /* obtain possibly-cached cvec for char class */
1502  NOTE(REG_ULOCALE);
1503  cv = cclasscvec(v, cls, (v->cflags & REG_ICASE));
1504  NOERR();
1505 
1506  /* build the arcs; this may cause color splitting */
1507  subcolorcvec(v, cv, lp, rp);
1508 }
1509 
1510 /*
1511  * charclasscomplement - generate arcs for a complemented character class
1512  *
1513  * This is used for both atoms (\W and sibling escapes) and for elements
1514  * of bracket expressions. In bracket expressions, it is the caller's
1515  * responsibility that there not be any open subcolors when this is called.
1516  */
1517 static void
1519  enum char_classes cls,
1520  struct state *lp,
1521  struct state *rp)
1522 {
1523  struct state *cstate;
1524  struct cvec *cv;
1525 
1526  /* make dummy state to hang temporary arcs on */
1527  cstate = newstate(v->nfa);
1528  NOERR();
1529 
1530  /* obtain possibly-cached cvec for char class */
1531  NOTE(REG_ULOCALE);
1532  cv = cclasscvec(v, cls, (v->cflags & REG_ICASE));
1533  NOERR();
1534 
1535  /* build arcs for char class; this may cause color splitting */
1536  subcolorcvec(v, cv, cstate, cstate);
1537  NOERR();
1538 
1539  /* clean up any subcolors in the arc set */
1540  okcolors(v->nfa, v->cm);
1541  NOERR();
1542 
1543  /* now build output arcs for the complement of the char class */
1544  colorcomplement(v->nfa, v->cm, PLAIN, cstate, lp, rp);
1545  NOERR();
1546 
1547  /* clean up dummy state */
1548  dropstate(v->nfa, cstate);
1549 }
1550 
1551 /*
1552  * scannum - scan a number
1553  */
1554 static int /* value, <= DUPMAX */
1555 scannum(struct vars *v)
1556 {
1557  int n = 0;
1558 
1559  while (SEE(DIGIT) && n < DUPMAX)
1560  {
1561  n = n * 10 + v->nextvalue;
1562  NEXT();
1563  }
1564  if (SEE(DIGIT) || n > DUPMAX)
1565  {
1566  ERR(REG_BADBR);
1567  return 0;
1568  }
1569  return n;
1570 }
1571 
1572 /*
1573  * repeat - replicate subNFA for quantifiers
1574  *
1575  * The sub-NFA strung from lp to rp is modified to represent m to n
1576  * repetitions of its initial contents.
1577  *
1578  * The duplication sequences used here are chosen carefully so that any
1579  * pointers starting out pointing into the subexpression end up pointing into
1580  * the last occurrence. (Note that it may not be strung between the same
1581  * left and right end states, however!) This used to be important for the
1582  * subRE tree, although the important bits are now handled by the in-line
1583  * code in parse(), and when this is called, it doesn't matter any more.
1584  */
1585 static void
1586 repeat(struct vars *v,
1587  struct state *lp,
1588  struct state *rp,
1589  int m,
1590  int n)
1591 {
1592 #define SOME 2
1593 #define INF 3
1594 #define PAIR(x, y) ((x)*4 + (y))
1595 #define REDUCE(x) ( ((x) == DUPINF) ? INF : (((x) > 1) ? SOME : (x)) )
1596  const int rm = REDUCE(m);
1597  const int rn = REDUCE(n);
1598  struct state *s;
1599  struct state *s2;
1600 
1601  switch (PAIR(rm, rn))
1602  {
1603  case PAIR(0, 0): /* empty string */
1604  delsub(v->nfa, lp, rp);
1605  EMPTYARC(lp, rp);
1606  break;
1607  case PAIR(0, 1): /* do as x| */
1608  EMPTYARC(lp, rp);
1609  break;
1610  case PAIR(0, SOME): /* do as x{1,n}| */
1611  repeat(v, lp, rp, 1, n);
1612  NOERR();
1613  EMPTYARC(lp, rp);
1614  break;
1615  case PAIR(0, INF): /* loop x around */
1616  s = newstate(v->nfa);
1617  NOERR();
1618  moveouts(v->nfa, lp, s);
1619  moveins(v->nfa, rp, s);
1620  EMPTYARC(lp, s);
1621  EMPTYARC(s, rp);
1622  break;
1623  case PAIR(1, 1): /* no action required */
1624  break;
1625  case PAIR(1, SOME): /* do as x{0,n-1}x = (x{1,n-1}|)x */
1626  s = newstate(v->nfa);
1627  NOERR();
1628  moveouts(v->nfa, lp, s);
1629  dupnfa(v->nfa, s, rp, lp, s);
1630  NOERR();
1631  repeat(v, lp, s, 1, n - 1);
1632  NOERR();
1633  EMPTYARC(lp, s);
1634  break;
1635  case PAIR(1, INF): /* add loopback arc */
1636  s = newstate(v->nfa);
1637  s2 = newstate(v->nfa);
1638  NOERR();
1639  moveouts(v->nfa, lp, s);
1640  moveins(v->nfa, rp, s2);
1641  EMPTYARC(lp, s);
1642  EMPTYARC(s2, rp);
1643  EMPTYARC(s2, s);
1644  break;
1645  case PAIR(SOME, SOME): /* do as x{m-1,n-1}x */
1646  s = newstate(v->nfa);
1647  NOERR();
1648  moveouts(v->nfa, lp, s);
1649  dupnfa(v->nfa, s, rp, lp, s);
1650  NOERR();
1651  repeat(v, lp, s, m - 1, n - 1);
1652  break;
1653  case PAIR(SOME, INF): /* do as x{m-1,}x */
1654  s = newstate(v->nfa);
1655  NOERR();
1656  moveouts(v->nfa, lp, s);
1657  dupnfa(v->nfa, s, rp, lp, s);
1658  NOERR();
1659  repeat(v, lp, s, m - 1, n);
1660  break;
1661  default:
1662  ERR(REG_ASSERT);
1663  break;
1664  }
1665 }
1666 
1667 /*
1668  * bracket - handle non-complemented bracket expression
1669  *
1670  * Also called from cbracket for complemented bracket expressions.
1671  */
1672 static void
1673 bracket(struct vars *v,
1674  struct state *lp,
1675  struct state *rp)
1676 {
1677  /*
1678  * We can't process complemented char classes (e.g. \W) immediately while
1679  * scanning the bracket expression, else color bookkeeping gets confused.
1680  * Instead, remember whether we saw any in have_cclassc[], and process
1681  * them at the end.
1682  */
1683  bool have_cclassc[NUM_CCLASSES];
1684  bool any_cclassc;
1685  int i;
1686 
1687  memset(have_cclassc, false, sizeof(have_cclassc));
1688 
1689  assert(SEE('['));
1690  NEXT();
1691  while (!SEE(']') && !SEE(EOS))
1692  brackpart(v, lp, rp, have_cclassc);
1693  assert(SEE(']') || ISERR());
1694 
1695  /* close up open subcolors from the positive bracket elements */
1696  okcolors(v->nfa, v->cm);
1697  NOERR();
1698 
1699  /* now handle any complemented elements */
1700  any_cclassc = false;
1701  for (i = 0; i < NUM_CCLASSES; i++)
1702  {
1703  if (have_cclassc[i])
1704  {
1705  charclasscomplement(v, (enum char_classes) i, lp, rp);
1706  NOERR();
1707  any_cclassc = true;
1708  }
1709  }
1710 
1711  /*
1712  * If we had any complemented elements, see if we can optimize the bracket
1713  * into a rainbow. Since a complemented element is the only way a WHITE
1714  * arc could get into the result, there's no point in checking otherwise.
1715  */
1716  if (any_cclassc)
1717  optimizebracket(v, lp, rp);
1718 }
1719 
1720 /*
1721  * cbracket - handle complemented bracket expression
1722  *
1723  * We do it by calling bracket() with dummy endpoints, and then complementing
1724  * the result. The alternative would be to invoke rainbow(), and then delete
1725  * arcs as the b.e. is seen... but that gets messy, and is really quite
1726  * infeasible now that rainbow() just puts out one RAINBOW arc.
1727  */
1728 static void
1729 cbracket(struct vars *v,
1730  struct state *lp,
1731  struct state *rp)
1732 {
1733  struct state *left = newstate(v->nfa);
1734  struct state *right = newstate(v->nfa);
1735 
1736  NOERR();
1737  bracket(v, left, right);
1738 
1739  /* in NLSTOP mode, ensure newline is not part of the result set */
1740  if (v->cflags & REG_NLSTOP)
1741  newarc(v->nfa, PLAIN, v->nlcolor, left, right);
1742  NOERR();
1743 
1744  assert(lp->nouts == 0); /* all outarcs will be ours */
1745 
1746  /*
1747  * Easy part of complementing, and all there is to do since the MCCE code
1748  * was removed. Note that the result of colorcomplement() cannot be a
1749  * rainbow, since we don't allow empty brackets; so there's no point in
1750  * calling optimizebracket() again.
1751  */
1752  colorcomplement(v->nfa, v->cm, PLAIN, left, lp, rp);
1753  NOERR();
1754  dropstate(v->nfa, left);
1755  assert(right->nins == 0);
1756  freestate(v->nfa, right);
1757 }
1758 
1759 /*
1760  * brackpart - handle one item (or range) within a bracket expression
1761  */
1762 static void
1763 brackpart(struct vars *v,
1764  struct state *lp,
1765  struct state *rp,
1766  bool *have_cclassc)
1767 {
1768  chr startc;
1769  chr endc;
1770  struct cvec *cv;
1771  enum char_classes cls;
1772  const chr *startp;
1773  const chr *endp;
1774 
1775  /* parse something, get rid of special cases, take shortcuts */
1776  switch (v->nexttype)
1777  {
1778  case RANGE: /* a-b-c or other botch */
1779  ERR(REG_ERANGE);
1780  return;
1781  break;
1782  case PLAIN:
1783  startc = v->nextvalue;
1784  NEXT();
1785  /* shortcut for ordinary chr (not range) */
1786  if (!SEE(RANGE))
1787  {
1788  onechr(v, startc, lp, rp);
1789  return;
1790  }
1791  NOERR();
1792  break;
1793  case COLLEL:
1794  startp = v->now;
1795  endp = scanplain(v);
1796  INSIST(startp < endp, REG_ECOLLATE);
1797  NOERR();
1798  startc = element(v, startp, endp);
1799  NOERR();
1800  break;
1801  case ECLASS:
1802  startp = v->now;
1803  endp = scanplain(v);
1804  INSIST(startp < endp, REG_ECOLLATE);
1805  NOERR();
1806  startc = element(v, startp, endp);
1807  NOERR();
1808  cv = eclass(v, startc, (v->cflags & REG_ICASE));
1809  NOERR();
1810  subcolorcvec(v, cv, lp, rp);
1811  return;
1812  break;
1813  case CCLASS:
1814  startp = v->now;
1815  endp = scanplain(v);
1816  INSIST(startp < endp, REG_ECTYPE);
1817  NOERR();
1818  cls = lookupcclass(v, startp, endp);
1819  NOERR();
1820  charclass(v, cls, lp, rp);
1821  return;
1822  break;
1823  case CCLASSS:
1824  charclass(v, (enum char_classes) v->nextvalue, lp, rp);
1825  NEXT();
1826  return;
1827  break;
1828  case CCLASSC:
1829  /* we cannot call charclasscomplement() immediately */
1830  have_cclassc[v->nextvalue] = true;
1831  NEXT();
1832  return;
1833  break;
1834  default:
1835  ERR(REG_ASSERT);
1836  return;
1837  break;
1838  }
1839 
1840  if (SEE(RANGE))
1841  {
1842  NEXT();
1843  switch (v->nexttype)
1844  {
1845  case PLAIN:
1846  case RANGE:
1847  endc = v->nextvalue;
1848  NEXT();
1849  NOERR();
1850  break;
1851  case COLLEL:
1852  startp = v->now;
1853  endp = scanplain(v);
1854  INSIST(startp < endp, REG_ECOLLATE);
1855  NOERR();
1856  endc = element(v, startp, endp);
1857  NOERR();
1858  break;
1859  default:
1860  ERR(REG_ERANGE);
1861  return;
1862  break;
1863  }
1864  }
1865  else
1866  endc = startc;
1867 
1868  /*
1869  * Ranges are unportable. Actually, standard C does guarantee that digits
1870  * are contiguous, but making that an exception is just too complicated.
1871  */
1872  if (startc != endc)
1873  NOTE(REG_UUNPORT);
1874  cv = range(v, startc, endc, (v->cflags & REG_ICASE));
1875  NOERR();
1876  subcolorcvec(v, cv, lp, rp);
1877 }
1878 
1879 /*
1880  * scanplain - scan PLAIN contents of [. etc.
1881  *
1882  * Certain bits of trickery in regc_lex.c know that this code does not try
1883  * to look past the final bracket of the [. etc.
1884  */
1885 static const chr * /* just after end of sequence */
1886 scanplain(struct vars *v)
1887 {
1888  const chr *endp;
1889 
1890  assert(SEE(COLLEL) || SEE(ECLASS) || SEE(CCLASS));
1891  NEXT();
1892 
1893  endp = v->now;
1894  while (SEE(PLAIN))
1895  {
1896  endp = v->now;
1897  NEXT();
1898  }
1899 
1900  assert(SEE(END) || ISERR());
1901  NEXT();
1902 
1903  return endp;
1904 }
1905 
1906 /*
1907  * onechr - fill in arcs for a plain character, and possible case complements
1908  * This is mostly a shortcut for efficient handling of the common case.
1909  */
1910 static void
1911 onechr(struct vars *v,
1912  chr c,
1913  struct state *lp,
1914  struct state *rp)
1915 {
1916  if (!(v->cflags & REG_ICASE))
1917  {
1918  color lastsubcolor = COLORLESS;
1919 
1920  subcoloronechr(v, c, lp, rp, &lastsubcolor);
1921  return;
1922  }
1923 
1924  /* rats, need general case anyway... */
1925  subcolorcvec(v, allcases(v, c), lp, rp);
1926 }
1927 
1928 /*
1929  * optimizebracket - see if bracket expression can be converted to RAINBOW
1930  *
1931  * Cases such as "[\s\S]" can produce a set of arcs of all colors, which we
1932  * can replace by a single RAINBOW arc for efficiency. (This might seem
1933  * like a silly way to write ".", but it's seemingly a common locution in
1934  * some other flavors of regex, so take the trouble to support it well.)
1935  */
1936 static void
1938  struct state *lp,
1939  struct state *rp)
1940 {
1941  struct colordesc *cd;
1942  struct colordesc *end = CDEND(v->cm);
1943  struct arc *a;
1944  bool israinbow;
1945 
1946  /*
1947  * Scan lp's out-arcs and transiently mark the mentioned colors. We
1948  * expect that all of lp's out-arcs are plain, non-RAINBOW arcs to rp.
1949  * (Note: there shouldn't be any pseudocolors yet, but check anyway.)
1950  */
1951  for (a = lp->outs; a != NULL; a = a->outchain)
1952  {
1953  assert(a->type == PLAIN);
1954  assert(a->co >= 0); /* i.e. not RAINBOW */
1955  assert(a->to == rp);
1956  cd = &v->cm->cd[a->co];
1957  assert(!UNUSEDCOLOR(cd) && !(cd->flags & PSEUDO));
1958  cd->flags |= COLMARK;
1959  }
1960 
1961  /* Scan colors, clear transient marks, check for unmarked live colors */
1962  israinbow = true;
1963  for (cd = v->cm->cd; cd < end; cd++)
1964  {
1965  if (cd->flags & COLMARK)
1966  cd->flags &= ~COLMARK;
1967  else if (!UNUSEDCOLOR(cd) && !(cd->flags & PSEUDO))
1968  israinbow = false;
1969  }
1970 
1971  /* Can't do anything if not all colors have arcs */
1972  if (!israinbow)
1973  return;
1974 
1975  /* OK, drop existing arcs and replace with a rainbow */
1976  while ((a = lp->outs) != NULL)
1977  freearc(v->nfa, a);
1978  newarc(v->nfa, PLAIN, RAINBOW, lp, rp);
1979 }
1980 
1981 /*
1982  * wordchrs - set up word-chr list for word-boundary stuff, if needed
1983  *
1984  * The list is kept as a bunch of circular arcs on an otherwise-unused state.
1985  *
1986  * Note that this must not be called while we have any open subcolors,
1987  * else construction of the list would confuse color bookkeeping.
1988  * Hence, we can't currently apply a similar optimization in
1989  * charclass[complement](), as those need to be usable within bracket
1990  * expressions.
1991  */
1992 static void
1993 wordchrs(struct vars *v)
1994 {
1995  struct state *cstate;
1996  struct cvec *cv;
1997 
1998  if (v->wordchrs != NULL)
1999  return; /* done already */
2000 
2001  /* make dummy state to hang the cache arcs on */
2002  cstate = newstate(v->nfa);
2003  NOERR();
2004 
2005  /* obtain possibly-cached cvec for \w characters */
2006  NOTE(REG_ULOCALE);
2007  cv = cclasscvec(v, CC_WORD, (v->cflags & REG_ICASE));
2008  NOERR();
2009 
2010  /* build the arcs; this may cause color splitting */
2011  subcolorcvec(v, cv, cstate, cstate);
2012  NOERR();
2013 
2014  /* close new open subcolors to ensure the cache entry is self-contained */
2015  okcolors(v->nfa, v->cm);
2016  NOERR();
2017 
2018  /* success! save the cache pointer */
2019  v->wordchrs = cstate;
2020 }
2021 
2022 /*
2023  * processlacon - generate the NFA representation of a LACON
2024  *
2025  * In the general case this is just newlacon() + newarc(), but some cases
2026  * can be optimized.
2027  */
2028 static void
2029 processlacon(struct vars *v,
2030  struct state *begin, /* start of parsed LACON sub-re */
2031  struct state *end, /* end of parsed LACON sub-re */
2032  int latype,
2033  struct state *lp, /* left state to hang it on */
2034  struct state *rp) /* right state to hang it on */
2035 {
2036  struct state *s1;
2037  int n;
2038 
2039  /*
2040  * Check for lookaround RE consisting of a single plain color arc (or set
2041  * of arcs); this would typically be a simple chr or a bracket expression.
2042  */
2043  s1 = single_color_transition(begin, end);
2044  switch (latype)
2045  {
2046  case LATYPE_AHEAD_POS:
2047  /* If lookahead RE is just colorset C, convert to AHEAD(C) */
2048  if (s1 != NULL)
2049  {
2050  cloneouts(v->nfa, s1, lp, rp, AHEAD);
2051  return;
2052  }
2053  break;
2054  case LATYPE_AHEAD_NEG:
2055  /* If lookahead RE is just colorset C, convert to AHEAD(^C)|$ */
2056  if (s1 != NULL)
2057  {
2058  colorcomplement(v->nfa, v->cm, AHEAD, s1, lp, rp);
2059  newarc(v->nfa, '$', 1, lp, rp);
2060  newarc(v->nfa, '$', 0, lp, rp);
2061  return;
2062  }
2063  break;
2064  case LATYPE_BEHIND_POS:
2065  /* If lookbehind RE is just colorset C, convert to BEHIND(C) */
2066  if (s1 != NULL)
2067  {
2068  cloneouts(v->nfa, s1, lp, rp, BEHIND);
2069  return;
2070  }
2071  break;
2072  case LATYPE_BEHIND_NEG:
2073  /* If lookbehind RE is just colorset C, convert to BEHIND(^C)|^ */
2074  if (s1 != NULL)
2075  {
2076  colorcomplement(v->nfa, v->cm, BEHIND, s1, lp, rp);
2077  newarc(v->nfa, '^', 1, lp, rp);
2078  newarc(v->nfa, '^', 0, lp, rp);
2079  return;
2080  }
2081  break;
2082  default:
2083  assert(NOTREACHED);
2084  }
2085 
2086  /* General case: we need a LACON subre and arc */
2087  n = newlacon(v, begin, end, latype);
2088  newarc(v->nfa, LACON, n, lp, rp);
2089 }
2090 
2091 /*
2092  * subre - allocate a subre
2093  */
2094 static struct subre *
2095 subre(struct vars *v,
2096  int op,
2097  int flags,
2098  struct state *begin,
2099  struct state *end)
2100 {
2101  struct subre *ret = v->treefree;
2102 
2103  /*
2104  * Checking for stack overflow here is sufficient to protect parse() and
2105  * its recursive subroutines.
2106  */
2107  if (STACK_TOO_DEEP(v->re))
2108  {
2109  ERR(REG_ETOOBIG);
2110  return NULL;
2111  }
2112 
2113  if (ret != NULL)
2114  v->treefree = ret->child;
2115  else
2116  {
2117  ret = (struct subre *) MALLOC(sizeof(struct subre));
2118  if (ret == NULL)
2119  {
2120  ERR(REG_ESPACE);
2121  return NULL;
2122  }
2123  ret->chain = v->treechain;
2124  v->treechain = ret;
2125  }
2126 
2127  assert(strchr("=b|.*(", op) != NULL);
2128 
2129  ret->op = op;
2130  ret->flags = flags;
2131  ret->latype = (char) -1;
2132  ret->id = 0; /* will be assigned later */
2133  ret->capno = 0;
2134  ret->backno = 0;
2135  ret->min = ret->max = 1;
2136  ret->child = NULL;
2137  ret->sibling = NULL;
2138  ret->begin = begin;
2139  ret->end = end;
2140  ZAPCNFA(ret->cnfa);
2141 
2142  return ret;
2143 }
2144 
2145 /*
2146  * freesubre - free a subRE subtree
2147  *
2148  * This frees child node(s) of the given subRE too,
2149  * but not its siblings.
2150  */
2151 static void
2152 freesubre(struct vars *v, /* might be NULL */
2153  struct subre *sr)
2154 {
2155  if (sr == NULL)
2156  return;
2157 
2158  if (sr->child != NULL)
2159  freesubreandsiblings(v, sr->child);
2160 
2161  freesrnode(v, sr);
2162 }
2163 
2164 /*
2165  * freesubreandsiblings - free a subRE subtree
2166  *
2167  * This frees child node(s) of the given subRE too,
2168  * as well as any following siblings.
2169  */
2170 static void
2171 freesubreandsiblings(struct vars *v, /* might be NULL */
2172  struct subre *sr)
2173 {
2174  while (sr != NULL)
2175  {
2176  struct subre *next = sr->sibling;
2177 
2178  freesubre(v, sr);
2179  sr = next;
2180  }
2181 }
2182 
2183 /*
2184  * freesrnode - free one node in a subRE subtree
2185  */
2186 static void
2187 freesrnode(struct vars *v, /* might be NULL */
2188  struct subre *sr)
2189 {
2190  if (sr == NULL)
2191  return;
2192 
2193  if (!NULLCNFA(sr->cnfa))
2194  freecnfa(&sr->cnfa);
2195  sr->flags = 0; /* in particular, not INUSE */
2196  sr->child = sr->sibling = NULL;
2197  sr->begin = sr->end = NULL;
2198 
2199  if (v != NULL && v->treechain != NULL)
2200  {
2201  /* we're still parsing, maybe we can reuse the subre */
2202  sr->child = v->treefree;
2203  v->treefree = sr;
2204  }
2205  else
2206  FREE(sr);
2207 }
2208 
2209 /*
2210  * removecaptures - remove unnecessary capture subREs
2211  *
2212  * If the caller said that it doesn't care about subexpression match data,
2213  * we may delete the "capture" markers on subREs that are not referenced
2214  * by any backrefs, and then simplify anything that's become non-messy.
2215  * Call this only if REG_NOSUB flag is set.
2216  */
2217 static void
2219  struct subre *t)
2220 {
2221  struct subre *t2;
2222 
2223  assert(t != NULL);
2224 
2225  /*
2226  * If this isn't itself a backref target, clear capno and tentatively
2227  * clear CAP flag.
2228  */
2229  if (!(t->flags & BRUSE))
2230  {
2231  t->capno = 0;
2232  t->flags &= ~CAP;
2233  }
2234 
2235  /* Now recurse to children */
2236  for (t2 = t->child; t2 != NULL; t2 = t2->sibling)
2237  {
2238  removecaptures(v, t2);
2239  /* Propagate child CAP flag back up, if it's still set */
2240  if (t2->flags & CAP)
2241  t->flags |= CAP;
2242  }
2243 
2244  /*
2245  * If t now contains neither captures nor backrefs, there's no longer any
2246  * need to care where its sub-match boundaries are, so we can reduce it to
2247  * a simple DFA node. (Note in particular that MIXED child greediness is
2248  * not a hindrance here, so we don't use the MESSY() macro.)
2249  */
2250  if ((t->flags & (CAP | BACKR)) == 0)
2251  {
2252  if (t->child)
2253  freesubreandsiblings(v, t->child);
2254  t->child = NULL;
2255  t->op = '=';
2256  t->flags &= ~MIXED;
2257  }
2258 }
2259 
2260 /*
2261  * numst - number tree nodes (assigning "id" indexes)
2262  */
2263 static int /* next number */
2264 numst(struct subre *t,
2265  int start) /* starting point for subtree numbers */
2266 {
2267  int i;
2268  struct subre *t2;
2269 
2270  assert(t != NULL);
2271 
2272  i = start;
2273  t->id = i++;
2274  for (t2 = t->child; t2 != NULL; t2 = t2->sibling)
2275  i = numst(t2, i);
2276  return i;
2277 }
2278 
2279 /*
2280  * markst - mark tree nodes as INUSE
2281  *
2282  * Note: this is a great deal more subtle than it looks. During initial
2283  * parsing of a regex, all subres are linked into the treechain list;
2284  * discarded ones are also linked into the treefree list for possible reuse.
2285  * After we are done creating all subres required for a regex, we run markst()
2286  * then cleanst(), which results in discarding all subres not reachable from
2287  * v->tree. We then clear v->treechain, indicating that subres must be found
2288  * by descending from v->tree. This changes the behavior of freesubre(): it
2289  * will henceforth FREE() unwanted subres rather than sticking them into the
2290  * treefree list. (Doing that any earlier would result in dangling links in
2291  * the treechain list.) This all means that freev() will clean up correctly
2292  * if invoked before or after markst()+cleanst(); but it would not work if
2293  * called partway through this state conversion, so we mustn't error out
2294  * in or between these two functions.
2295  */
2296 static void
2297 markst(struct subre *t)
2298 {
2299  struct subre *t2;
2300 
2301  assert(t != NULL);
2302 
2303  t->flags |= INUSE;
2304  for (t2 = t->child; t2 != NULL; t2 = t2->sibling)
2305  markst(t2);
2306 }
2307 
2308 /*
2309  * cleanst - free any tree nodes not marked INUSE
2310  */
2311 static void
2312 cleanst(struct vars *v)
2313 {
2314  struct subre *t;
2315  struct subre *next;
2316 
2317  for (t = v->treechain; t != NULL; t = next)
2318  {
2319  next = t->chain;
2320  if (!(t->flags & INUSE))
2321  FREE(t);
2322  }
2323  v->treechain = NULL;
2324  v->treefree = NULL; /* just on general principles */
2325 }
2326 
2327 /*
2328  * nfatree - turn a subRE subtree into a tree of compacted NFAs
2329  */
2330 static long /* optimize results from top node */
2331 nfatree(struct vars *v,
2332  struct subre *t,
2333  FILE *f) /* for debug output */
2334 {
2335  struct subre *t2;
2336 
2337  assert(t != NULL && t->begin != NULL);
2338 
2339  for (t2 = t->child; t2 != NULL; t2 = t2->sibling)
2340  (DISCARD) nfatree(v, t2, f);
2341 
2342  return nfanode(v, t, 0, f);
2343 }
2344 
2345 /*
2346  * nfanode - do one NFA for nfatree or lacons
2347  *
2348  * If converttosearch is true, apply makesearch() to the NFA.
2349  */
2350 static long /* optimize results */
2351 nfanode(struct vars *v,
2352  struct subre *t,
2353  int converttosearch,
2354  FILE *f) /* for debug output */
2355 {
2356  struct nfa *nfa;
2357  long ret = 0;
2358 
2359  assert(t->begin != NULL);
2360 
2361 #ifdef REG_DEBUG
2362  if (f != NULL)
2363  {
2364  char idbuf[50];
2365 
2366  fprintf(f, "\n\n\n========= TREE NODE %s ==========\n",
2367  stid(t, idbuf, sizeof(idbuf)));
2368  }
2369 #endif
2370  nfa = newnfa(v, v->cm, v->nfa);
2371  NOERRZ();
2372  dupnfa(nfa, t->begin, t->end, nfa->init, nfa->final);
2373  if (!ISERR())
2374  specialcolors(nfa);
2375  if (!ISERR())
2376  ret = optimize(nfa, f);
2377  if (converttosearch && !ISERR())
2378  makesearch(v, nfa);
2379  if (!ISERR())
2380  compact(nfa, &t->cnfa);
2381 
2382  freenfa(nfa);
2383  return ret;
2384 }
2385 
2386 /*
2387  * newlacon - allocate a lookaround-constraint subRE
2388  */
2389 static int /* lacon number */
2390 newlacon(struct vars *v,
2391  struct state *begin,
2392  struct state *end,
2393  int latype)
2394 {
2395  int n;
2396  struct subre *newlacons;
2397  struct subre *sub;
2398 
2399  if (v->nlacons == 0)
2400  {
2401  n = 1; /* skip 0th */
2402  newlacons = (struct subre *) MALLOC(2 * sizeof(struct subre));
2403  }
2404  else
2405  {
2406  n = v->nlacons;
2407  newlacons = (struct subre *) REALLOC(v->lacons,
2408  (n + 1) * sizeof(struct subre));
2409  }
2410  if (newlacons == NULL)
2411  {
2412  ERR(REG_ESPACE);
2413  return 0;
2414  }
2415  v->lacons = newlacons;
2416  v->nlacons = n + 1;
2417  sub = &v->lacons[n];
2418  sub->begin = begin;
2419  sub->end = end;
2420  sub->latype = latype;
2421  ZAPCNFA(sub->cnfa);
2422  return n;
2423 }
2424 
2425 /*
2426  * freelacons - free lookaround-constraint subRE vector
2427  */
2428 static void
2429 freelacons(struct subre *subs,
2430  int n)
2431 {
2432  struct subre *sub;
2433  int i;
2434 
2435  assert(n > 0);
2436  for (sub = subs + 1, i = n - 1; i > 0; sub++, i--) /* no 0th */
2437  if (!NULLCNFA(sub->cnfa))
2438  freecnfa(&sub->cnfa);
2439  FREE(subs);
2440 }
2441 
2442 /*
2443  * rfree - free a whole RE (insides of regfree)
2444  */
2445 static void
2447 {
2448  struct guts *g;
2449 
2450  if (re == NULL || re->re_magic != REMAGIC)
2451  return;
2452 
2453  re->re_magic = 0; /* invalidate RE */
2454  g = (struct guts *) re->re_guts;
2455  re->re_guts = NULL;
2456  re->re_fns = NULL;
2457  if (g != NULL)
2458  {
2459  g->magic = 0;
2460  freecm(&g->cmap);
2461  if (g->tree != NULL)
2462  freesubre((struct vars *) NULL, g->tree);
2463  if (g->lacons != NULL)
2464  freelacons(g->lacons, g->nlacons);
2465  if (!NULLCNFA(g->search))
2466  freecnfa(&g->search);
2467  FREE(g);
2468  }
2469 }
2470 
2471 /*
2472  * rcancelrequested - check for external request to cancel regex operation
2473  *
2474  * Return nonzero to fail the operation with error code REG_CANCEL,
2475  * zero to keep going
2476  *
2477  * The current implementation is Postgres-specific. If we ever get around
2478  * to splitting the regex code out as a standalone library, there will need
2479  * to be some API to let applications define a callback function for this.
2480  */
2481 static int
2483 {
2485 }
2486 
2487 /*
2488  * rstacktoodeep - check for stack getting dangerously deep
2489  *
2490  * Return nonzero to fail the operation with error code REG_ETOOBIG,
2491  * zero to keep going
2492  *
2493  * The current implementation is Postgres-specific. If we ever get around
2494  * to splitting the regex code out as a standalone library, there will need
2495  * to be some API to let applications define a callback function for this.
2496  */
2497 static int
2499 {
2500  return stack_is_too_deep();
2501 }
2502 
2503 #ifdef REG_DEBUG
2504 
2505 /*
2506  * dump - dump an RE in human-readable form
2507  */
2508 static void
2509 dump(regex_t *re,
2510  FILE *f)
2511 {
2512  struct guts *g;
2513  int i;
2514 
2515  if (re->re_magic != REMAGIC)
2516  fprintf(f, "bad magic number (0x%x not 0x%x)\n", re->re_magic,
2517  REMAGIC);
2518  if (re->re_guts == NULL)
2519  {
2520  fprintf(f, "NULL guts!!!\n");
2521  return;
2522  }
2523  g = (struct guts *) re->re_guts;
2524  if (g->magic != GUTSMAGIC)
2525  fprintf(f, "bad guts magic number (0x%x not 0x%x)\n", g->magic,
2526  GUTSMAGIC);
2527 
2528  fprintf(f, "\n\n\n========= DUMP ==========\n");
2529  fprintf(f, "nsub %d, info 0%lo, csize %d, ntree %d\n",
2530  (int) re->re_nsub, re->re_info, re->re_csize, g->ntree);
2531 
2532  dumpcolors(&g->cmap, f);
2533  if (!NULLCNFA(g->search))
2534  {
2535  fprintf(f, "\nsearch:\n");
2536  dumpcnfa(&g->search, f);
2537  }
2538  for (i = 1; i < g->nlacons; i++)
2539  {
2540  struct subre *lasub = &g->lacons[i];
2541  const char *latype;
2542 
2543  switch (lasub->latype)
2544  {
2545  case LATYPE_AHEAD_POS:
2546  latype = "positive lookahead";
2547  break;
2548  case LATYPE_AHEAD_NEG:
2549  latype = "negative lookahead";
2550  break;
2551  case LATYPE_BEHIND_POS:
2552  latype = "positive lookbehind";
2553  break;
2554  case LATYPE_BEHIND_NEG:
2555  latype = "negative lookbehind";
2556  break;
2557  default:
2558  latype = "???";
2559  break;
2560  }
2561  fprintf(f, "\nla%d (%s):\n", i, latype);
2562  dumpcnfa(&lasub->cnfa, f);
2563  }
2564  fprintf(f, "\n");
2565  dumpst(g->tree, f, 0);
2566 }
2567 
2568 /*
2569  * dumpst - dump a subRE tree
2570  */
2571 static void
2572 dumpst(struct subre *t,
2573  FILE *f,
2574  int nfapresent) /* is the original NFA still around? */
2575 {
2576  if (t == NULL)
2577  fprintf(f, "null tree\n");
2578  else
2579  stdump(t, f, nfapresent);
2580  fflush(f);
2581 }
2582 
2583 /*
2584  * stdump - recursive guts of dumpst
2585  */
2586 static void
2587 stdump(struct subre *t,
2588  FILE *f,
2589  int nfapresent) /* is the original NFA still around? */
2590 {
2591  char idbuf[50];
2592  struct subre *t2;
2593 
2594  fprintf(f, "%s. `%c'", stid(t, idbuf, sizeof(idbuf)), t->op);
2595  if (t->flags & LONGER)
2596  fprintf(f, " longest");
2597  if (t->flags & SHORTER)
2598  fprintf(f, " shortest");
2599  if (t->flags & MIXED)
2600  fprintf(f, " hasmixed");
2601  if (t->flags & CAP)
2602  fprintf(f, " hascapture");
2603  if (t->flags & BACKR)
2604  fprintf(f, " hasbackref");
2605  if (t->flags & BRUSE)
2606  fprintf(f, " isreferenced");
2607  if (!(t->flags & INUSE))
2608  fprintf(f, " UNUSED");
2609  if (t->latype != (char) -1)
2610  fprintf(f, " latype(%d)", t->latype);
2611  if (t->capno != 0)
2612  fprintf(f, " capture(%d)", t->capno);
2613  if (t->backno != 0)
2614  fprintf(f, " backref(%d)", t->backno);
2615  if (t->min != 1 || t->max != 1)
2616  {
2617  fprintf(f, " {%d,", t->min);
2618  if (t->max != DUPINF)
2619  fprintf(f, "%d", t->max);
2620  fprintf(f, "}");
2621  }
2622  if (nfapresent)
2623  fprintf(f, " %ld-%ld", (long) t->begin->no, (long) t->end->no);
2624  if (t->child != NULL)
2625  fprintf(f, " C:%s", stid(t->child, idbuf, sizeof(idbuf)));
2626  /* printing second child isn't necessary, but it is often helpful */
2627  if (t->child != NULL && t->child->sibling != NULL)
2628  fprintf(f, " C2:%s", stid(t->child->sibling, idbuf, sizeof(idbuf)));
2629  if (t->sibling != NULL)
2630  fprintf(f, " S:%s", stid(t->sibling, idbuf, sizeof(idbuf)));
2631  if (!NULLCNFA(t->cnfa))
2632  {
2633  fprintf(f, "\n");
2634  dumpcnfa(&t->cnfa, f);
2635  }
2636  fprintf(f, "\n");
2637  for (t2 = t->child; t2 != NULL; t2 = t2->sibling)
2638  stdump(t2, f, nfapresent);
2639 }
2640 
2641 /*
2642  * stid - identify a subtree node for dumping
2643  */
2644 static const char * /* points to buf or constant string */
2645 stid(struct subre *t,
2646  char *buf,
2647  size_t bufsize)
2648 {
2649  /* big enough for hex int or decimal t->id? */
2650  if (bufsize < sizeof(void *) * 2 + 3 || bufsize < sizeof(t->id) * 3 + 1)
2651  return "unable";
2652  if (t->id != 0)
2653  sprintf(buf, "%d", t->id);
2654  else
2655  sprintf(buf, "%p", t);
2656  return buf;
2657 }
2658 #endif /* REG_DEBUG */
2659 
2660 
2661 #include "regc_lex.c"
2662 #include "regc_color.c"
2663 #include "regc_nfa.c"
2664 #include "regc_cvec.c"
2665 #include "regc_pg_locale.c"
2666 #include "regc_locale.c"
#define FREE(ptr)
Definition: cryptohash.c:37
volatile sig_atomic_t InterruptPending
Definition: globals.c:30
volatile sig_atomic_t QueryCancelPending
Definition: globals.c:31
volatile sig_atomic_t ProcDiePending
Definition: globals.c:32
static bool debug
Definition: initdb.c:145
int y
Definition: isn.c:72
int b
Definition: isn.c:70
int x
Definition: isn.c:71
int init
Definition: isn.c:75
int a
Definition: isn.c:69
int j
Definition: isn.c:74
int i
Definition: isn.c:73
if(TABLE==NULL||TABLE_index==NULL)
Definition: isn.c:77
static void const char fflush(stdout)
unsigned int pg_wchar
Definition: mbprint.c:31
const void size_t len
static char * buf
Definition: pg_test_fsync.c:67
#define sprintf
Definition: port.h:240
#define fprintf
Definition: port.h:242
bool stack_is_too_deep(void)
Definition: postgres.c:3468
unsigned int Oid
Definition: postgres_ext.h:31
char * c
char * s1
char * s2
char string[11]
Definition: preproc-type.c:52
void pg_set_regex_collation(Oid collation)
static void freecvec(struct cvec *cv)
#define COLLEL
Definition: regcomp.c:334
static void mergeins(struct nfa *nfa, struct state *s, struct arc **arcarray, int arccount)
static void subcoloronechr(struct vars *v, chr ch, struct state *lp, struct state *rp, color *lastsubcolor)
static int newhicolorrow(struct colormap *cm, int oldrow)
#define NWBDRY
Definition: regcomp.c:345
static int pg_wc_islower(pg_wchar c)
static int pg_wc_isword(pg_wchar c)
static void cleartraverse(struct nfa *nfa, struct state *s)
#define REDUCE(x)
static void cparc(struct nfa *nfa, struct arc *oa, struct state *from, struct state *to)
static void subcolorcvec(struct vars *v, struct cvec *cv, struct state *lp, struct state *rp)
static struct cvec * cclasscvec(struct vars *v, enum char_classes cclasscode, int cases)
static void clonesuccessorstates(struct nfa *nfa, struct state *ssource, struct state *sclone, struct state *spredecessor, struct arc *refarc, char *curdonemap, char *outerdonemap, int nstates)
#define INF
static struct state * emptyreachable(struct nfa *nfa, struct state *s, struct state *lastfound, struct arc **inarcsorig)
static int pg_wc_isspace(pg_wchar c)
static pg_wchar pg_wc_tolower(pg_wchar c)
#define NOTE(b)
Definition: regcomp.c:325
static int combine(struct nfa *nfa, struct arc *con, struct arc *a)
static void freecolor(struct colormap *cm, color co)
static void copyouts(struct nfa *nfa, struct state *oldState, struct state *newState)
static void wordchrs(struct vars *v)
Definition: regcomp.c:1993
static int sortins_cmp(const void *a, const void *b)
static int pg_wc_ispunct(pg_wchar c)
#define NOERR()
Definition: regcomp.c:321
static void cleanup(struct nfa *nfa)
static int findconstraintloop(struct nfa *nfa, struct state *s)
#define END
Definition: regcomp.c:337
static void compact(struct nfa *nfa, struct cnfa *cnfa)
static int pg_wc_isgraph(pg_wchar c)
static void specialcolors(struct nfa *nfa)
static void freesubreandsiblings(struct vars *v, struct subre *sr)
Definition: regcomp.c:2171
static void dupnfa(struct nfa *nfa, struct state *start, struct state *stop, struct state *from, struct state *to)
static struct cvec * range(struct vars *v, chr a, chr b, int cases)
#define SBEGIN
Definition: regcomp.c:346
static long analyze(struct nfa *nfa)
#define ISERR()
Definition: regcomp.c:317
static void duptraverse(struct nfa *nfa, struct state *s, struct state *stmp)
static void freesubre(struct vars *v, struct subre *sr)
Definition: regcomp.c:2152
static void newarc(struct nfa *nfa, int t, color co, struct state *from, struct state *to)
static void repeat(struct vars *v, struct state *lp, struct state *rp, int m, int n)
Definition: regcomp.c:1586
static int lexescape(struct vars *v)
static pg_wchar pg_wc_toupper(pg_wchar c)
static void makesearch(struct vars *v, struct nfa *nfa)
Definition: regcomp.c:621
static void moresubs(struct vars *v, int wanted)
Definition: regcomp.c:555
static int casecmp(const chr *x, const chr *y, size_t len)
static bool checkmatchall_recurse(struct nfa *nfa, struct state *s, bool **haspaths)
static const struct fns functions
Definition: regcomp.c:357
static void newhicolorcols(struct colormap *cm)
static struct subre * parsebranch(struct vars *v, int stopper, int type, struct state *left, struct state *right, int partial)
Definition: regcomp.c:785
static void freenfa(struct nfa *nfa)
static void optimizebracket(struct vars *v, struct state *lp, struct state *rp)
Definition: regcomp.c:1937
static int pg_wc_isprint(pg_wchar c)
#define CCLASSS
Definition: regcomp.c:338
#define EMPTYARC(x, y)
Definition: regcomp.c:326
static void createarc(struct nfa *nfa, int t, color co, struct state *from, struct state *to)
#define ERR(e)
Definition: regcomp.c:320
static int isconstraintarc(struct arc *a)
static int pg_wc_isalnum(pg_wchar c)
static struct arc * allocarc(struct nfa *nfa)
static struct state * single_color_transition(struct state *s1, struct state *s2)
#define CCLASS
Definition: regcomp.c:336
static int rstacktoodeep(void)
Definition: regcomp.c:2498
#define WBDRY
Definition: regcomp.c:344
static void fixempties(struct nfa *nfa, FILE *f)
static int pg_wc_isdigit(pg_wchar c)
static void skip(struct vars *v)
int pg_regcomp(regex_t *re, const chr *string, size_t len, int flags, Oid collation)
Definition: regcomp.c:372
static enum char_classes lookupcclass(struct vars *v, const chr *startp, const chr *endp)
static void cleanst(struct vars *v)
Definition: regcomp.c:2312
#define SEE(t)
Definition: regcomp.c:314
static void copyins(struct nfa *nfa, struct state *oldState, struct state *newState)
static int push(struct nfa *nfa, struct arc *con, struct state **intermediates)
static int rcancelrequested(void)
Definition: regcomp.c:2482
static color newcolor(struct colormap *cm)
#define PAIR(x, y)
static void moveouts(struct nfa *nfa, struct state *oldState, struct state *newState)
static chr lexdigits(struct vars *v, int base, int minlen, int maxlen)
static int hasconstraintout(struct state *s)
static void freearc(struct nfa *nfa, struct arc *victim)
#define DIGIT
Definition: regcomp.c:332
static void checkmatchall(struct nfa *nfa)
static void addchr(struct cvec *cv, chr c)
static color subcolorhi(struct colormap *cm, color *pco)
#define ARCV(t, val)
static void colorchain(struct colormap *cm, struct arc *a)
static int scannum(struct vars *v)
Definition: regcomp.c:1555
static struct state * newfstate(struct nfa *nfa, int flag)
static void sortins(struct nfa *nfa, struct state *s)
static void cloneouts(struct nfa *nfa, struct state *old, struct state *from, struct state *to, int type)
static struct nfa * newnfa(struct vars *v, struct colormap *cm, struct nfa *parent)
static int carc_cmp(const void *a, const void *b)
static struct subre * parseqatom(struct vars *v, int stopper, int type, struct state *lp, struct state *rp, struct subre *top)
Definition: regcomp.c:838
#define CCLASSC
Definition: regcomp.c:339
static void freecm(struct colormap *cm)
static long optimize(struct nfa *nfa, FILE *f)
static void uncolorchain(struct colormap *cm, struct arc *a)
#define CNOERR()
static void rfree(regex_t *re)
Definition: regcomp.c:2446
static struct cvec * eclass(struct vars *v, chr c, int cases)
static void sortouts(struct nfa *nfa, struct state *s)
#define NOERRN()
Definition: regcomp.c:322
static const chr * scanplain(struct vars *v)
Definition: regcomp.c:1886
static void deltraverse(struct nfa *nfa, struct state *leftend, struct state *s)
#define SOME
static void dropstate(struct nfa *nfa, struct state *s)
static void okcolors(struct nfa *nfa, struct colormap *cm)
#define BEHIND
Definition: regcomp.c:343
static void addrange(struct cvec *cv, chr from, chr to)
static color maxcolor(struct colormap *cm)
static void initcm(struct vars *v, struct colormap *cm)
static void removetraverse(struct nfa *nfa, struct state *s)
static chr newline(void)
static void charclass(struct vars *v, enum char_classes cls, struct state *lp, struct state *rp)
Definition: regcomp.c:1494
static void bracket(struct vars *v, struct state *lp, struct state *rp)
Definition: regcomp.c:1673
static void cbracket(struct vars *v, struct state *lp, struct state *rp)
Definition: regcomp.c:1729
static void pushfwd(struct nfa *nfa, FILE *f)
static color pseudocolor(struct colormap *cm)
static int cmp(const chr *x, const chr *y, size_t len)
static struct subre * subre(struct vars *v, int op, int flags, struct state *begin, struct state *end)
Definition: regcomp.c:2095
static int hasnonemptyout(struct state *s)
static long nfanode(struct vars *v, struct subre *t, int converttosearch, FILE *f)
Definition: regcomp.c:2351
static void freesrnode(struct vars *v, struct subre *sr)
Definition: regcomp.c:2187
#define ECLASS
Definition: regcomp.c:335
static void pullback(struct nfa *nfa, FILE *f)
#define BACKREF
Definition: regcomp.c:333
#define LACON
Definition: regcomp.c:341
static void markcanreach(struct nfa *nfa, struct state *s, struct state *okay, struct state *mark)
static void removecaptures(struct vars *v, struct subre *t)
Definition: regcomp.c:2218
static int brenext(struct vars *v, chr c)
#define EOS
Definition: regcomp.c:330
static void lexstart(struct vars *v)
static void nonword(struct vars *v, int dir, struct state *lp, struct state *rp)
Definition: regcomp.c:1458
#define AHEAD
Definition: regcomp.c:342
static struct state * newstate(struct nfa *nfa)
static void delsub(struct nfa *nfa, struct state *lp, struct state *rp)
static struct cvec * clearcvec(struct cvec *cv)
static void prefixes(struct vars *v)
static void moveins(struct nfa *nfa, struct state *oldState, struct state *newState)
static bool check_in_colors_match(struct state *s, color co1, color co2)
#define PLAIN
Definition: regcomp.c:331
#define SEND
Definition: regcomp.c:347
static void removeconstraints(struct nfa *nfa, struct state *start, struct state *stop)
static void charclasscomplement(struct vars *v, enum char_classes cls, struct state *lp, struct state *rp)
Definition: regcomp.c:1518
#define RANGE
Definition: regcomp.c:340
static struct subre * parse(struct vars *v, int stopper, int type, struct state *init, struct state *final)
Definition: regcomp.c:717
static int sortouts_cmp(const void *a, const void *b)
#define EAT(t)
Definition: regcomp.c:315
static int newlacon(struct vars *v, struct state *begin, struct state *end, int latype)
Definition: regcomp.c:2390
#define INSIST(c, e)
Definition: regcomp.c:324
static color subcolor(struct colormap *cm, chr c)
static struct cvec * getcvec(struct vars *v, int nchrs, int nranges)
static void rainbow(struct nfa *nfa, struct colormap *cm, int type, color but, struct state *from, struct state *to)
static struct cvec * allcases(struct vars *v, chr c)
static void colorcomplement(struct nfa *nfa, struct colormap *cm, int type, struct state *of, struct state *from, struct state *to)
static void carcsort(struct carc *first, size_t n)
static int pull(struct nfa *nfa, struct arc *con, struct state **intermediates)
static void subcoloronerange(struct vars *v, chr from, chr to, struct state *lp, struct state *rp, color *lastsubcolor)
static void changearctarget(struct arc *a, struct state *newto)
static chr element(struct vars *v, const chr *startp, const chr *endp)
#define NOERRZ()
Definition: regcomp.c:323
static void freelacons(struct subre *subs, int n)
Definition: regcomp.c:2429
static struct arc * findarc(struct state *s, int type, color co)
static void processlacon(struct vars *v, struct state *begin, struct state *end, int latype, struct state *lp, struct state *rp)
Definition: regcomp.c:2029
static void changearcsource(struct arc *a, struct state *newfrom)
static void subcoloronerow(struct vars *v, int rownum, struct state *lp, struct state *rp, color *lastsubcolor)
static void freestate(struct nfa *nfa, struct state *s)
static void dumpnfa(struct nfa *nfa, FILE *f)
static void brackpart(struct vars *v, struct state *lp, struct state *rp, bool *have_cclassc)
Definition: regcomp.c:1763
static void markreachable(struct nfa *nfa, struct state *s, struct state *okay, struct state *mark)
static int before(chr x, chr y)
static chr chrnamed(struct vars *v, const chr *startp, const chr *endp, chr lastresort)
static void onechr(struct vars *v, chr c, struct state *lp, struct state *rp)
Definition: regcomp.c:1911
static int numst(struct subre *t, int start)
Definition: regcomp.c:2264
static void word(struct vars *v, int dir, struct state *lp, struct state *rp)
Definition: regcomp.c:1476
static void fixconstraintloops(struct nfa *nfa, FILE *f)
static int freev(struct vars *v, int err)
Definition: regcomp.c:592
static long nfatree(struct vars *v, struct subre *t, FILE *f)
Definition: regcomp.c:2331
static int pg_wc_isupper(pg_wchar c)
static bool check_out_colors_match(struct state *s, color co1, color co2)
static void breakconstraintloop(struct nfa *nfa, struct state *sinitial)
static int pg_wc_isalpha(pg_wchar c)
static void markst(struct subre *t)
Definition: regcomp.c:2297
#define NEXT()
Definition: regcomp.c:313
static int cclass_column_index(struct colormap *cm, chr c)
static void freecnfa(struct cnfa *cnfa)
static color newsub(struct colormap *cm, color co)
static struct cvec * newcvec(int nchrs, int nranges)
static int next(struct vars *v)
#define REALLOC(p, n)
Definition: regcustom.h:54
#define MALLOC(n)
Definition: regcustom.h:52
pg_wchar chr
Definition: regcustom.h:58
#define assert(x)
Definition: regcustom.h:55
#define REG_ICASE
Definition: regex.h:106
#define REG_DUMP
Definition: regex.h:115
#define REG_ECTYPE
Definition: regex.h:141
#define REG_PROGRESS
Definition: regex.h:117
#define REG_ASSERT
Definition: regex.h:151
#define REG_UPBOTCH
Definition: regex.h:65
#define REG_BADRPT
Definition: regex.h:150
#define REG_ADVANCED
Definition: regex.h:103
#define REG_EXPANDED
Definition: regex.h:108
#define REG_NLANCH
Definition: regex.h:110
#define REG_INVARG
Definition: regex.h:152
#define REG_EXTENDED
Definition: regex.h:101
#define REG_NLSTOP
Definition: regex.h:109
#define REG_ADVF
Definition: regex.h:102
#define REG_UUNSPEC
Definition: regex.h:68
#define REG_ETOOBIG
Definition: regex.h:155
#define REG_ERANGE
Definition: regex.h:148
#define REG_ESUBREG
Definition: regex.h:143
#define REG_BADBR
Definition: regex.h:147
#define REG_NEWLINE
Definition: regex.h:111
#define REG_NOSUB
Definition: regex.h:107
#define REG_USHORTEST
Definition: regex.h:73
#define REG_ULOCALE
Definition: regex.h:70
#define REG_ECOLLATE
Definition: regex.h:140
#define REG_UUNPORT
Definition: regex.h:69
#define REG_EPAREN
Definition: regex.h:145
#define REG_ESPACE
Definition: regex.h:149
#define REG_QUOTE
Definition: regex.h:104
#define BACKR
Definition: regguts.h:479
#define NUM_CCLASSES
Definition: regguts.h:139
#define LATYPE_AHEAD_NEG
Definition: regguts.h:100
#define PSEUDO
Definition: regguts.h:181
#define RAINBOW
Definition: regguts.h:154
#define LATYPE_BEHIND_POS
Definition: regguts.h:101
#define STACK_TOO_DEEP(re)
Definition: regguts.h:520
#define CAP
Definition: regguts.h:478
#define ZAPCNFA(cnfa)
Definition: regguts.h:429
#define REMAGIC
Definition: regguts.h:96
short color
Definition: regguts.h:150
#define COMBINE(f1, f2)
Definition: regguts.h:489
#define UP(f)
Definition: regguts.h:485
#define PREF(f)
Definition: regguts.h:487
#define NOTREACHED
Definition: regguts.h:91
#define GUTSMAGIC
Definition: regguts.h:530
#define COLORLESS
Definition: regguts.h:153
#define LATYPE_BEHIND_NEG
Definition: regguts.h:102
#define DUPINF
Definition: regguts.h:94
#define COLMARK
Definition: regguts.h:182
#define DUPMAX
Definition: regguts.h:93
#define UNUSEDCOLOR(cd)
Definition: regguts.h:185
#define LATYPE_IS_AHEAD(la)
Definition: regguts.h:104
#define NULLCNFA(cnfa)
Definition: regguts.h:431
#define LONGER
Definition: regguts.h:475
char_classes
Definition: regguts.h:134
@ CC_WORD
Definition: regguts.h:136
#define INUSE
Definition: regguts.h:481
#define CDEND(cm)
Definition: regguts.h:232
#define MESSY(f)
Definition: regguts.h:486
#define BRUSE
Definition: regguts.h:480
#define DISCARD
Definition: regguts.h:58
#define MIXED
Definition: regguts.h:477
#define VS(x)
Definition: regguts.h:61
#define MATCHALL
Definition: regguts.h:407
#define SHORTER
Definition: regguts.h:476
#define LATYPE_AHEAD_POS
Definition: regguts.h:99
Definition: regguts.h:291
struct state * from
Definition: regguts.h:294
color co
Definition: regguts.h:293
struct state * to
Definition: regguts.h:295
Definition: regguts.h:396
Definition: regguts.h:402
int flags
Definition: regguts.h:179
struct colordesc * cd
Definition: regguts.h:231
Definition: regguts.h:274
int nchrs
Definition: regguts.h:275
int cclasscode
Definition: regguts.h:281
int nranges
Definition: regguts.h:278
Definition: regguts.h:511
Definition: regguts.h:528
struct subre * tree
Definition: regguts.h:534
struct subre * lacons
Definition: regguts.h:539
int magic
Definition: regguts.h:529
long info
Definition: regguts.h:532
struct cnfa search
Definition: regguts.h:535
int ntree
Definition: regguts.h:536
int cflags
Definition: regguts.h:531
size_t nsub
Definition: regguts.h:533
int nlacons
Definition: regguts.h:540
struct colormap cmap
Definition: regguts.h:537
Definition: regguts.h:344
struct vars * v
Definition: regguts.h:364
struct state * final
Definition: regguts.h:347
int maxmatchall
Definition: regguts.h:363
color bos[2]
Definition: regguts.h:359
int flags
Definition: regguts.h:361
struct state * pre
Definition: regguts.h:345
struct colormap * cm
Definition: regguts.h:358
struct nfa * parent
Definition: regguts.h:365
struct state * init
Definition: regguts.h:346
Definition: regex.h:56
char * re_guts
Definition: regex.h:78
long re_info
Definition: regex.h:59
int re_csize
Definition: regex.h:74
size_t re_nsub
Definition: regex.h:58
int re_magic
Definition: regex.h:57
Oid re_collation
Definition: regex.h:76
char * re_fns
Definition: regex.h:79
Definition: regguts.h:318
int nins
Definition: regguts.h:322
int nouts
Definition: regguts.h:323
struct state * tmp
Definition: regguts.h:326
struct arc * outs
Definition: regguts.h:325
struct arc * ins
Definition: regguts.h:324
int no
Definition: regguts.h:319
Definition: regguts.h:472
int backno
Definition: regguts.h:493
char op
Definition: regguts.h:473
struct subre * chain
Definition: regguts.h:501
struct state * end
Definition: regguts.h:499
short min
Definition: regguts.h:494
short max
Definition: regguts.h:495
struct subre * sibling
Definition: regguts.h:497
char flags
Definition: regguts.h:474
int id
Definition: regguts.h:491
struct cnfa cnfa
Definition: regguts.h:500
char latype
Definition: regguts.h:490
struct subre * child
Definition: regguts.h:496
int capno
Definition: regguts.h:492
struct state * begin
Definition: regguts.h:498
Definition: regcomp.c:282
const chr * now
Definition: regcomp.c:284
struct colormap * cm
Definition: regcomp.c:297
struct subre * tree
Definition: regcomp.c:300
struct subre ** subs
Definition: regcomp.c:293
int nlacons
Definition: regcomp.c:307
const chr * stop
Definition: regcomp.c:285
struct subre * lacons
Definition: regcomp.c:306
size_t spaceused
Definition: regcomp.c:309
int err
Definition: regcomp.c:286
int cflags
Definition: regcomp.c:287
struct subre * treechain
Definition: regcomp.c:301
int lexcon
Definition: regcomp.c:291
chr nextvalue
Definition: regcomp.c:290
int ntree
Definition: regcomp.c:303
regex_t * re
Definition: regcomp.c:283
struct subre * sub10[10]
Definition: regcomp.c:295
struct cvec * cv2
Definition: regcomp.c:305
struct subre * treefree
Definition: regcomp.c:302
struct nfa * nfa
Definition: regcomp.c:296
size_t nsubs
Definition: regcomp.c:294
struct state * wordchrs
Definition: regcomp.c:299
int nexttype
Definition: regcomp.c:289
int nsubexp
Definition: regcomp.c:292
struct cvec * cv
Definition: regcomp.c:304
color nlcolor
Definition: regcomp.c:298
int lasttype
Definition: regcomp.c:288
char * flag(int b)
Definition: test-ctype.c:33