Age Owner Branch data TLA Line data Source code
1 : : /*
2 : : * NFA utilities.
3 : : * This file is #included by regcomp.c.
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/regc_nfa.c
32 : : *
33 : : *
34 : : * One or two things that technically ought to be in here
35 : : * are actually in color.c, thanks to some incestuous relationships in
36 : : * the color chains.
37 : : */
38 : :
39 : : #define NISERR() VISERR(nfa->v)
40 : : #define NERR(e) VERR(nfa->v, (e))
41 : :
42 : :
43 : : /*
44 : : * newnfa - set up an NFA
45 : : */
46 : : static struct nfa * /* the NFA, or NULL */
2489 tgl@sss.pgh.pa.us 47 :CBC 9008 : newnfa(struct vars *v,
48 : : struct colormap *cm,
49 : : struct nfa *parent) /* NULL if primary NFA */
50 : : {
51 : : struct nfa *nfa;
52 : :
7559 bruce@momjian.us 53 : 9008 : nfa = (struct nfa *) MALLOC(sizeof(struct nfa));
7739 tgl@sss.pgh.pa.us 54 [ - + ]: 9008 : if (nfa == NULL)
55 : : {
3168 tgl@sss.pgh.pa.us 56 [ # # ]:UBC 0 : ERR(REG_ESPACE);
7739 57 : 0 : return NULL;
58 : : }
59 : :
60 : : /* Make the NFA minimally valid, so freenfa() will behave sanely */
7739 tgl@sss.pgh.pa.us 61 :CBC 9008 : nfa->states = NULL;
62 : 9008 : nfa->slast = NULL;
1143 63 : 9008 : nfa->freestates = NULL;
64 : 9008 : nfa->freearcs = NULL;
65 : 9008 : nfa->lastsb = NULL;
66 : 9008 : nfa->lastab = NULL;
67 : 9008 : nfa->lastsbused = 0;
68 : 9008 : nfa->lastabused = 0;
7739 69 : 9008 : nfa->nstates = 0;
70 : 9008 : nfa->cm = cm;
71 : 9008 : nfa->v = v;
72 : 9008 : nfa->bos[0] = nfa->bos[1] = COLORLESS;
73 : 9008 : nfa->eos[0] = nfa->eos[1] = COLORLESS;
1149 74 : 9008 : nfa->flags = 0;
75 : 9008 : nfa->minmatchall = nfa->maxmatchall = -1;
5946 76 : 9008 : nfa->parent = parent; /* Precedes newfstate so parent is valid. */
77 : :
78 : : /* Create required infrastructure */
7739 79 : 9008 : nfa->post = newfstate(nfa, '@'); /* number 0 */
2489 80 : 9008 : nfa->pre = newfstate(nfa, '>'); /* number 1 */
7559 bruce@momjian.us 81 : 9008 : nfa->init = newstate(nfa); /* may become invalid later */
7739 tgl@sss.pgh.pa.us 82 : 9008 : nfa->final = newstate(nfa);
7559 bruce@momjian.us 83 [ - + ]: 9008 : if (ISERR())
84 : : {
7739 tgl@sss.pgh.pa.us 85 :UBC 0 : freenfa(nfa);
86 : 0 : return NULL;
87 : : }
7739 tgl@sss.pgh.pa.us 88 :CBC 9008 : rainbow(nfa, nfa->cm, PLAIN, COLORLESS, nfa->pre, nfa->init);
89 : 9008 : newarc(nfa, '^', 1, nfa->pre, nfa->init);
90 : 9008 : newarc(nfa, '^', 0, nfa->pre, nfa->init);
91 : 9008 : rainbow(nfa, nfa->cm, PLAIN, COLORLESS, nfa->final, nfa->post);
92 : 9008 : newarc(nfa, '$', 1, nfa->final, nfa->post);
93 : 9008 : newarc(nfa, '$', 0, nfa->final, nfa->post);
94 : :
7559 bruce@momjian.us 95 [ - + ]: 9008 : if (ISERR())
96 : : {
7739 tgl@sss.pgh.pa.us 97 :UBC 0 : freenfa(nfa);
98 : 0 : return NULL;
99 : : }
7739 tgl@sss.pgh.pa.us 100 :CBC 9008 : return nfa;
101 : : }
102 : :
103 : : /*
104 : : * freenfa - free an entire NFA
105 : : */
106 : : static void
2489 107 : 9008 : freenfa(struct nfa *nfa)
108 : : {
109 : : struct statebatch *sb;
110 : : struct statebatch *sbnext;
111 : : struct arcbatch *ab;
112 : : struct arcbatch *abnext;
113 : :
1143 114 [ + + ]: 18852 : for (sb = nfa->lastsb; sb != NULL; sb = sbnext)
115 : : {
116 : 9844 : sbnext = sb->next;
117 : 9844 : nfa->v->spaceused -= STATEBATCHSIZE(sb->nstates);
118 : 9844 : FREE(sb);
119 : : }
120 : 9008 : nfa->lastsb = NULL;
121 [ + + ]: 26107 : for (ab = nfa->lastab; ab != NULL; ab = abnext)
122 : : {
123 : 17099 : abnext = ab->next;
124 : 17099 : nfa->v->spaceused -= ARCBATCHSIZE(ab->narcs);
125 : 17099 : FREE(ab);
126 : : }
127 : 9008 : nfa->lastab = NULL;
128 : :
7739 129 : 9008 : nfa->nstates = -1;
130 : 9008 : FREE(nfa);
131 : 9008 : }
132 : :
133 : : /*
134 : : * newstate - allocate an NFA state, with zero flag value
135 : : */
136 : : static struct state * /* NULL on error */
2489 137 : 245732 : newstate(struct nfa *nfa)
138 : : {
139 : : struct state *s;
140 : :
141 : : /*
142 : : * This is a handy place to check for operation cancel during regex
143 : : * compilation, since no code path will go very long without making a new
144 : : * state or arc.
145 : : */
372 tmunro@postgresql.or 146 [ - + ]: 245732 : INTERRUPT(nfa->v->re);
147 : :
148 : : /* first, recycle anything that's on the freelist */
1143 tgl@sss.pgh.pa.us 149 [ + + ]: 245732 : if (nfa->freestates != NULL)
150 : : {
151 : 16377 : s = nfa->freestates;
152 : 16377 : nfa->freestates = s->next;
153 : : }
154 : : /* otherwise, is there anything left in the last statebatch? */
155 [ + + + + ]: 229355 : else if (nfa->lastsb != NULL && nfa->lastsbused < nfa->lastsb->nstates)
156 : : {
157 : 219511 : s = &nfa->lastsb->s[nfa->lastsbused++];
158 : : }
159 : : /* otherwise, need to allocate a new statebatch */
160 : : else
161 : : {
162 : : struct statebatch *newSb;
163 : : size_t nstates;
164 : :
3103 165 [ - + ]: 9844 : if (nfa->v->spaceused >= REG_MAX_COMPILE_SPACE)
166 : : {
3103 tgl@sss.pgh.pa.us 167 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
168 : 0 : return NULL;
169 : : }
1143 tgl@sss.pgh.pa.us 170 [ + + ]:CBC 9844 : nstates = (nfa->lastsb != NULL) ? nfa->lastsb->nstates * 2 : FIRSTSBSIZE;
171 [ + + ]: 9844 : if (nstates > MAXSBSIZE)
172 : 25 : nstates = MAXSBSIZE;
173 : 9844 : newSb = (struct statebatch *) MALLOC(STATEBATCHSIZE(nstates));
174 [ - + ]: 9844 : if (newSb == NULL)
175 : : {
7739 tgl@sss.pgh.pa.us 176 [ # # ]:UBC 0 : NERR(REG_ESPACE);
177 : 0 : return NULL;
178 : : }
1143 tgl@sss.pgh.pa.us 179 :CBC 9844 : nfa->v->spaceused += STATEBATCHSIZE(nstates);
180 : 9844 : newSb->nstates = nstates;
181 : 9844 : newSb->next = nfa->lastsb;
182 : 9844 : nfa->lastsb = newSb;
183 : 9844 : nfa->lastsbused = 1;
184 : 9844 : s = &newSb->s[0];
185 : : }
186 : :
7739 187 [ - + ]: 245732 : assert(nfa->nstates >= 0);
188 : 245732 : s->no = nfa->nstates++;
189 : 245732 : s->flag = 0;
190 [ + + ]: 245732 : if (nfa->states == NULL)
191 : 9008 : nfa->states = s;
192 : 245732 : s->nins = 0;
193 : 245732 : s->ins = NULL;
194 : 245732 : s->nouts = 0;
195 : 245732 : s->outs = NULL;
196 : 245732 : s->tmp = NULL;
197 : 245732 : s->next = NULL;
7559 bruce@momjian.us 198 [ + + ]: 245732 : if (nfa->slast != NULL)
199 : : {
7739 tgl@sss.pgh.pa.us 200 [ - + ]: 236724 : assert(nfa->slast->next == NULL);
201 : 236724 : nfa->slast->next = s;
202 : : }
203 : 245732 : s->prev = nfa->slast;
204 : 245732 : nfa->slast = s;
205 : 245732 : return s;
206 : : }
207 : :
208 : : /*
209 : : * newfstate - allocate an NFA state with a specified flag value
210 : : */
211 : : static struct state * /* NULL on error */
2489 212 : 18016 : newfstate(struct nfa *nfa, int flag)
213 : : {
214 : : struct state *s;
215 : :
7739 216 : 18016 : s = newstate(nfa);
217 [ + - ]: 18016 : if (s != NULL)
7559 bruce@momjian.us 218 : 18016 : s->flag = (char) flag;
7739 tgl@sss.pgh.pa.us 219 : 18016 : return s;
220 : : }
221 : :
222 : : /*
223 : : * dropstate - delete a state's inarcs and outarcs and free it
224 : : */
225 : : static void
2489 226 : 103567 : dropstate(struct nfa *nfa,
227 : : struct state *s)
228 : : {
229 : : struct arc *a;
230 : :
7739 231 [ + + ]: 121979 : while ((a = s->ins) != NULL)
232 : 18412 : freearc(nfa, a);
233 [ + + ]: 171332 : while ((a = s->outs) != NULL)
234 : 67765 : freearc(nfa, a);
235 : 103567 : freestate(nfa, s);
236 : 103567 : }
237 : :
238 : : /*
239 : : * freestate - free a state, which has no in-arcs or out-arcs
240 : : */
241 : : static void
2489 242 : 108166 : freestate(struct nfa *nfa,
243 : : struct state *s)
244 : : {
7739 245 [ - + ]: 108166 : assert(s != NULL);
246 [ + - - + ]: 108166 : assert(s->nins == 0 && s->nouts == 0);
247 : :
248 : 108166 : s->no = FREESTATE;
249 : 108166 : s->flag = 0;
250 [ + + ]: 108166 : if (s->next != NULL)
251 : 102437 : s->next->prev = s->prev;
252 : : else
253 : : {
254 [ - + ]: 5729 : assert(s == nfa->slast);
255 : 5729 : nfa->slast = s->prev;
256 : : }
257 [ + - ]: 108166 : if (s->prev != NULL)
258 : 108166 : s->prev->next = s->next;
259 : : else
260 : : {
7739 tgl@sss.pgh.pa.us 261 [ # # ]:UBC 0 : assert(s == nfa->states);
262 : 0 : nfa->states = s->next;
263 : : }
7739 tgl@sss.pgh.pa.us 264 :CBC 108166 : s->prev = NULL;
1143 265 : 108166 : s->next = nfa->freestates; /* don't delete it, put it on the free list */
266 : 108166 : nfa->freestates = s;
7739 267 : 108166 : }
268 : :
269 : : /*
270 : : * newarc - set up a new arc within an NFA
271 : : *
272 : : * This function checks to make sure that no duplicate arcs are created.
273 : : * In general we never want duplicates.
274 : : *
275 : : * However: in principle, a RAINBOW arc is redundant with any plain arc
276 : : * (unless that arc is for a pseudocolor). But we don't try to recognize
277 : : * that redundancy, either here or in allied operations such as moveins().
278 : : * The pseudocolor consideration makes that more costly than it seems worth.
279 : : */
280 : : static void
2489 281 : 925663 : newarc(struct nfa *nfa,
282 : : int t,
283 : : color co,
284 : : struct state *from,
285 : : struct state *to)
286 : : {
287 : : struct arc *a;
288 : :
7739 289 [ + - - + ]: 925663 : assert(from != NULL && to != NULL);
290 : :
291 : : /*
292 : : * This is a handy place to check for operation cancel during regex
293 : : * compilation, since no code path will go very long without making a new
294 : : * state or arc.
295 : : */
372 tmunro@postgresql.or 296 [ - + ]: 925663 : INTERRUPT(nfa->v->re);
297 : :
298 : : /* check for duplicate arc, using whichever chain is shorter */
3103 tgl@sss.pgh.pa.us 299 [ + + ]: 925663 : if (from->nouts <= to->nins)
300 : : {
301 [ + + ]: 2972463 : for (a = from->outs; a != NULL; a = a->outchain)
302 [ + + + + : 2544420 : if (a->to == to && a->co == co && a->type == t)
+ + ]
303 : 84960 : return;
304 : : }
305 : : else
306 : : {
307 [ + + ]: 38381876 : for (a = to->ins; a != NULL; a = a->inchain)
308 [ + + + + : 38054748 : if (a->from == from && a->co == co && a->type == t)
+ + ]
309 : 85532 : return;
310 : : }
311 : :
312 : : /* no dup, so create the arc */
313 : 755171 : createarc(nfa, t, co, from, to);
314 : : }
315 : :
316 : : /*
317 : : * createarc - create a new arc within an NFA
318 : : *
319 : : * This function must *only* be used after verifying that there is no existing
320 : : * identical arc (same type/color/from/to).
321 : : */
322 : : static void
2489 323 : 8692706 : createarc(struct nfa *nfa,
324 : : int t,
325 : : color co,
326 : : struct state *from,
327 : : struct state *to)
328 : : {
329 : : struct arc *a;
330 : :
1143 331 : 8692706 : a = allocarc(nfa);
7739 332 [ + + ]: 8692706 : if (NISERR())
333 : 5709 : return;
334 [ - + ]: 8686997 : assert(a != NULL);
335 : :
336 : 8686997 : a->type = t;
2795 337 : 8686997 : a->co = co;
7739 338 : 8686997 : a->to = to;
339 : 8686997 : a->from = from;
340 : :
341 : : /*
342 : : * Put the new arc on the beginning, not the end, of the chains; it's
343 : : * simpler here, and freearc() is the same cost either way. See also the
344 : : * logic in moveins() and its cohorts, as well as fixempties().
345 : : */
346 : 8686997 : a->inchain = to->ins;
3103 347 : 8686997 : a->inchainRev = NULL;
348 [ + + ]: 8686997 : if (to->ins)
349 : 8395420 : to->ins->inchainRev = a;
7739 350 : 8686997 : to->ins = a;
351 : 8686997 : a->outchain = from->outs;
3103 352 : 8686997 : a->outchainRev = NULL;
353 [ + + ]: 8686997 : if (from->outs)
354 : 8433721 : from->outs->outchainRev = a;
7739 355 : 8686997 : from->outs = a;
356 : :
357 : 8686997 : from->nouts++;
358 : 8686997 : to->nins++;
359 : :
360 [ + + + + : 8686997 : if (COLORED(a) && nfa->parent == NULL)
+ + + + +
+ ]
361 : 788950 : colorchain(nfa->cm, a);
362 : : }
363 : :
364 : : /*
365 : : * allocarc - allocate a new arc within an NFA
366 : : */
367 : : static struct arc * /* NULL for failure */
1143 368 : 8692706 : allocarc(struct nfa *nfa)
369 : : {
370 : : struct arc *a;
371 : :
372 : : /* first, recycle anything that's on the freelist */
373 [ + + ]: 8692706 : if (nfa->freearcs != NULL)
374 : : {
375 : 679151 : a = nfa->freearcs;
376 : 679151 : nfa->freearcs = a->freechain;
377 : : }
378 : : /* otherwise, is there anything left in the last arcbatch? */
379 [ + + + + ]: 8013555 : else if (nfa->lastab != NULL && nfa->lastabused < nfa->lastab->narcs)
380 : : {
381 : 7990747 : a = &nfa->lastab->a[nfa->lastabused++];
382 : : }
383 : : /* otherwise, need to allocate a new arcbatch */
384 : : else
385 : : {
386 : : struct arcbatch *newAb;
387 : : size_t narcs;
388 : :
3103 389 [ + + ]: 22808 : if (nfa->v->spaceused >= REG_MAX_COMPILE_SPACE)
390 : : {
391 [ + + ]: 5709 : NERR(REG_ETOOBIG);
392 : 5709 : return NULL;
393 : : }
1143 394 [ + + ]: 17099 : narcs = (nfa->lastab != NULL) ? nfa->lastab->narcs * 2 : FIRSTABSIZE;
395 [ + + ]: 17099 : if (narcs > MAXABSIZE)
396 : 7529 : narcs = MAXABSIZE;
397 : 17099 : newAb = (struct arcbatch *) MALLOC(ARCBATCHSIZE(narcs));
5904 398 [ - + ]: 17099 : if (newAb == NULL)
399 : : {
7739 tgl@sss.pgh.pa.us 400 [ # # ]:UBC 0 : NERR(REG_ESPACE);
401 : 0 : return NULL;
402 : : }
1143 tgl@sss.pgh.pa.us 403 :CBC 17099 : nfa->v->spaceused += ARCBATCHSIZE(narcs);
404 : 17099 : newAb->narcs = narcs;
405 : 17099 : newAb->next = nfa->lastab;
406 : 17099 : nfa->lastab = newAb;
407 : 17099 : nfa->lastabused = 1;
408 : 17099 : a = &newAb->a[0];
409 : : }
410 : :
7739 411 : 8686997 : return a;
412 : : }
413 : :
414 : : /*
415 : : * freearc - free an arc
416 : : */
417 : : static void
2489 418 : 785722 : freearc(struct nfa *nfa,
419 : : struct arc *victim)
420 : : {
7739 421 : 785722 : struct state *from = victim->from;
422 : 785722 : struct state *to = victim->to;
423 : : struct arc *predecessor;
424 : :
425 [ - + ]: 785722 : assert(victim->type != 0);
426 : :
427 : : /* take it off color chain if necessary */
428 [ + + + + : 785722 : if (COLORED(victim) && nfa->parent == NULL)
+ + + + +
+ ]
429 : 364277 : uncolorchain(nfa->cm, victim);
430 : :
431 : : /* take it off source's out-chain */
432 [ - + ]: 785722 : assert(from != NULL);
3103 433 : 785722 : predecessor = victim->outchainRev;
434 [ + + ]: 785722 : if (predecessor == NULL)
435 : : {
436 [ - + ]: 224968 : assert(from->outs == victim);
7739 437 : 224968 : from->outs = victim->outchain;
438 : : }
439 : : else
440 : : {
3103 441 [ - + ]: 560754 : assert(predecessor->outchain == victim);
442 : 560754 : predecessor->outchain = victim->outchain;
443 : : }
444 [ + + ]: 785722 : if (victim->outchain != NULL)
445 : : {
446 [ - + ]: 505070 : assert(victim->outchain->outchainRev == victim);
447 : 505070 : victim->outchain->outchainRev = predecessor;
448 : : }
7739 449 : 785722 : from->nouts--;
450 : :
451 : : /* take it off target's in-chain */
452 [ - + ]: 785722 : assert(to != NULL);
3103 453 : 785722 : predecessor = victim->inchainRev;
454 [ + + ]: 785722 : if (predecessor == NULL)
455 : : {
456 [ - + ]: 376839 : assert(to->ins == victim);
7739 457 : 376839 : to->ins = victim->inchain;
458 : : }
459 : : else
460 : : {
3103 461 [ - + ]: 408883 : assert(predecessor->inchain == victim);
462 : 408883 : predecessor->inchain = victim->inchain;
463 : : }
464 [ + + ]: 785722 : if (victim->inchain != NULL)
465 : : {
466 [ - + ]: 520884 : assert(victim->inchain->inchainRev == victim);
467 : 520884 : victim->inchain->inchainRev = predecessor;
468 : : }
7739 469 : 785722 : to->nins--;
470 : :
471 : : /* clean up and place on NFA's free list */
472 : 785722 : victim->type = 0;
473 : 785722 : victim->from = NULL; /* precautions... */
474 : 785722 : victim->to = NULL;
475 : 785722 : victim->inchain = NULL;
3103 476 : 785722 : victim->inchainRev = NULL;
7739 477 : 785722 : victim->outchain = NULL;
3103 478 : 785722 : victim->outchainRev = NULL;
1143 479 : 785722 : victim->freechain = nfa->freearcs;
480 : 785722 : nfa->freearcs = victim;
7739 481 : 785722 : }
482 : :
483 : : /*
484 : : * changearcsource - flip an arc to have a different from state
485 : : *
486 : : * Caller must have verified that there is no pre-existing duplicate arc.
487 : : */
488 : : static void
1143 489 : 294 : changearcsource(struct arc *a, struct state *newfrom)
490 : : {
491 : 294 : struct state *oldfrom = a->from;
492 : : struct arc *predecessor;
493 : :
494 [ - + ]: 294 : assert(oldfrom != newfrom);
495 : :
496 : : /* take it off old source's out-chain */
497 [ - + ]: 294 : assert(oldfrom != NULL);
498 : 294 : predecessor = a->outchainRev;
499 [ + - ]: 294 : if (predecessor == NULL)
500 : : {
501 [ - + ]: 294 : assert(oldfrom->outs == a);
502 : 294 : oldfrom->outs = a->outchain;
503 : : }
504 : : else
505 : : {
1143 tgl@sss.pgh.pa.us 506 [ # # ]:UBC 0 : assert(predecessor->outchain == a);
507 : 0 : predecessor->outchain = a->outchain;
508 : : }
1143 tgl@sss.pgh.pa.us 509 [ + + ]:CBC 294 : if (a->outchain != NULL)
510 : : {
511 [ - + ]: 287 : assert(a->outchain->outchainRev == a);
512 : 287 : a->outchain->outchainRev = predecessor;
513 : : }
514 : 294 : oldfrom->nouts--;
515 : :
516 : 294 : a->from = newfrom;
517 : :
518 : : /* prepend it to new source's out-chain */
519 : 294 : a->outchain = newfrom->outs;
520 : 294 : a->outchainRev = NULL;
521 [ + - ]: 294 : if (newfrom->outs)
522 : 294 : newfrom->outs->outchainRev = a;
523 : 294 : newfrom->outs = a;
524 : 294 : newfrom->nouts++;
525 : 294 : }
526 : :
527 : : /*
528 : : * changearctarget - flip an arc to have a different to state
529 : : *
530 : : * Caller must have verified that there is no pre-existing duplicate arc.
531 : : */
532 : : static void
2489 533 : 160 : changearctarget(struct arc *a, struct state *newto)
534 : : {
3103 535 : 160 : struct state *oldto = a->to;
536 : : struct arc *predecessor;
537 : :
538 [ - + ]: 160 : assert(oldto != newto);
539 : :
540 : : /* take it off old target's in-chain */
541 [ - + ]: 160 : assert(oldto != NULL);
542 : 160 : predecessor = a->inchainRev;
543 [ + - ]: 160 : if (predecessor == NULL)
544 : : {
545 [ - + ]: 160 : assert(oldto->ins == a);
546 : 160 : oldto->ins = a->inchain;
547 : : }
548 : : else
549 : : {
3103 tgl@sss.pgh.pa.us 550 [ # # ]:UBC 0 : assert(predecessor->inchain == a);
551 : 0 : predecessor->inchain = a->inchain;
552 : : }
3103 tgl@sss.pgh.pa.us 553 [ + + ]:CBC 160 : if (a->inchain != NULL)
554 : : {
555 [ - + ]: 156 : assert(a->inchain->inchainRev == a);
556 : 156 : a->inchain->inchainRev = predecessor;
557 : : }
558 : 160 : oldto->nins--;
559 : :
560 : 160 : a->to = newto;
561 : :
562 : : /* prepend it to new target's in-chain */
563 : 160 : a->inchain = newto->ins;
564 : 160 : a->inchainRev = NULL;
565 [ + - ]: 160 : if (newto->ins)
566 : 160 : newto->ins->inchainRev = a;
567 : 160 : newto->ins = a;
568 : 160 : newto->nins++;
569 : 160 : }
570 : :
571 : : /*
572 : : * hasnonemptyout - Does state have a non-EMPTY out arc?
573 : : */
574 : : static int
2489 575 : 110806 : hasnonemptyout(struct state *s)
576 : : {
577 : : struct arc *a;
578 : :
4056 579 [ + + ]: 124899 : for (a = s->outs; a != NULL; a = a->outchain)
580 : : {
581 [ + + ]: 122925 : if (a->type != EMPTY)
582 : 108832 : return 1;
583 : : }
584 : 1974 : return 0;
585 : : }
586 : :
587 : : /*
588 : : * findarc - find arc, if any, from given source with given type and color
589 : : * If there is more than one such arc, the result is random.
590 : : */
591 : : static struct arc *
2489 592 : 286 : findarc(struct state *s,
593 : : int type,
594 : : color co)
595 : : {
596 : : struct arc *a;
597 : :
7739 598 [ + + ]: 845 : for (a = s->outs; a != NULL; a = a->outchain)
599 [ + - + + ]: 560 : if (a->type == type && a->co == co)
600 : 1 : return a;
601 : 285 : return NULL;
602 : : }
603 : :
604 : : /*
605 : : * cparc - allocate a new arc within an NFA, copying details from old one
606 : : */
607 : : static void
2489 608 : 738533 : cparc(struct nfa *nfa,
609 : : struct arc *oa,
610 : : struct state *from,
611 : : struct state *to)
612 : : {
7739 613 : 738533 : newarc(nfa, oa->type, oa->co, from, to);
614 : 738533 : }
615 : :
616 : : /*
617 : : * sortins - sort the in arcs of a state by from/color/type
618 : : */
619 : : static void
2489 620 : 15307 : sortins(struct nfa *nfa,
621 : : struct state *s)
622 : : {
623 : : struct arc **sortarray;
624 : : struct arc *a;
3103 625 : 15307 : int n = s->nins;
626 : : int i;
627 : :
628 [ + + ]: 15307 : if (n <= 1)
629 : 2 : return; /* nothing to do */
630 : : /* make an array of arc pointers ... */
631 : 15305 : sortarray = (struct arc **) MALLOC(n * sizeof(struct arc *));
632 [ - + ]: 15305 : if (sortarray == NULL)
633 : : {
3103 tgl@sss.pgh.pa.us 634 [ # # ]:UBC 0 : NERR(REG_ESPACE);
635 : 0 : return;
636 : : }
3103 tgl@sss.pgh.pa.us 637 :CBC 15305 : i = 0;
638 [ + + ]: 67952 : for (a = s->ins; a != NULL; a = a->inchain)
639 : 52647 : sortarray[i++] = a;
640 [ - + ]: 15305 : assert(i == n);
641 : : /* ... sort the array */
642 : 15305 : qsort(sortarray, n, sizeof(struct arc *), sortins_cmp);
643 : : /* ... and rebuild arc list in order */
644 : : /* it seems worth special-casing first and last items to simplify loop */
645 : 15305 : a = sortarray[0];
646 : 15305 : s->ins = a;
647 : 15305 : a->inchain = sortarray[1];
648 : 15305 : a->inchainRev = NULL;
649 [ + + ]: 37342 : for (i = 1; i < n - 1; i++)
650 : : {
651 : 22037 : a = sortarray[i];
652 : 22037 : a->inchain = sortarray[i + 1];
653 : 22037 : a->inchainRev = sortarray[i - 1];
654 : : }
655 : 15305 : a = sortarray[i];
656 : 15305 : a->inchain = NULL;
657 : 15305 : a->inchainRev = sortarray[i - 1];
658 : 15305 : FREE(sortarray);
659 : : }
660 : :
661 : : static int
662 : 37893009 : sortins_cmp(const void *a, const void *b)
663 : : {
2489 664 : 37893009 : const struct arc *aa = *((const struct arc *const *) a);
665 : 37893009 : const struct arc *bb = *((const struct arc *const *) b);
666 : :
667 : : /* we check the fields in the order they are most likely to be different */
3103 668 [ + + ]: 37893009 : if (aa->from->no < bb->from->no)
669 : 30138645 : return -1;
670 [ + + ]: 7754364 : if (aa->from->no > bb->from->no)
671 : 7524122 : return 1;
672 [ + + ]: 230242 : if (aa->co < bb->co)
673 : 122427 : return -1;
674 [ + + ]: 107815 : if (aa->co > bb->co)
675 : 106219 : return 1;
676 [ + + ]: 1596 : if (aa->type < bb->type)
677 : 56 : return -1;
678 [ + + ]: 1540 : if (aa->type > bb->type)
679 : 29 : return 1;
680 : 1511 : return 0;
681 : : }
682 : :
683 : : /*
684 : : * sortouts - sort the out arcs of a state by to/color/type
685 : : */
686 : : static void
2489 687 : 16 : sortouts(struct nfa *nfa,
688 : : struct state *s)
689 : : {
690 : : struct arc **sortarray;
691 : : struct arc *a;
3103 692 : 16 : int n = s->nouts;
693 : : int i;
694 : :
695 [ - + ]: 16 : if (n <= 1)
3103 tgl@sss.pgh.pa.us 696 :UBC 0 : return; /* nothing to do */
697 : : /* make an array of arc pointers ... */
3103 tgl@sss.pgh.pa.us 698 :CBC 16 : sortarray = (struct arc **) MALLOC(n * sizeof(struct arc *));
699 [ - + ]: 16 : if (sortarray == NULL)
700 : : {
3103 tgl@sss.pgh.pa.us 701 [ # # ]:UBC 0 : NERR(REG_ESPACE);
702 : 0 : return;
703 : : }
3103 tgl@sss.pgh.pa.us 704 :CBC 16 : i = 0;
705 [ + + ]: 484 : for (a = s->outs; a != NULL; a = a->outchain)
706 : 468 : sortarray[i++] = a;
707 [ - + ]: 16 : assert(i == n);
708 : : /* ... sort the array */
709 : 16 : qsort(sortarray, n, sizeof(struct arc *), sortouts_cmp);
710 : : /* ... and rebuild arc list in order */
711 : : /* it seems worth special-casing first and last items to simplify loop */
712 : 16 : a = sortarray[0];
713 : 16 : s->outs = a;
714 : 16 : a->outchain = sortarray[1];
715 : 16 : a->outchainRev = NULL;
716 [ + + ]: 452 : for (i = 1; i < n - 1; i++)
717 : : {
718 : 436 : a = sortarray[i];
719 : 436 : a->outchain = sortarray[i + 1];
720 : 436 : a->outchainRev = sortarray[i - 1];
721 : : }
722 : 16 : a = sortarray[i];
723 : 16 : a->outchain = NULL;
724 : 16 : a->outchainRev = sortarray[i - 1];
725 : 16 : FREE(sortarray);
726 : : }
727 : :
728 : : static int
729 : 2746 : sortouts_cmp(const void *a, const void *b)
730 : : {
2489 731 : 2746 : const struct arc *aa = *((const struct arc *const *) a);
732 : 2746 : const struct arc *bb = *((const struct arc *const *) b);
733 : :
734 : : /* we check the fields in the order they are most likely to be different */
3103 735 [ + + ]: 2746 : if (aa->to->no < bb->to->no)
736 : 305 : return -1;
737 [ + + ]: 2441 : if (aa->to->no > bb->to->no)
738 : 80 : return 1;
739 [ + + ]: 2361 : if (aa->co < bb->co)
740 : 1281 : return -1;
741 [ + + ]: 1080 : if (aa->co > bb->co)
742 : 1058 : return 1;
743 [ + + ]: 22 : if (aa->type < bb->type)
744 : 1 : return -1;
745 [ + + ]: 21 : if (aa->type > bb->type)
746 : 7 : return 1;
747 : 14 : return 0;
748 : : }
749 : :
750 : : /*
751 : : * Common decision logic about whether to use arc-by-arc operations or
752 : : * sort/merge. If there's just a few source arcs we cannot recoup the
753 : : * cost of sorting the destination arc list, no matter how large it is.
754 : : * Otherwise, limit the number of arc-by-arc comparisons to about 1000
755 : : * (a somewhat arbitrary choice, but the breakeven point would probably
756 : : * be machine dependent anyway).
757 : : */
758 : : #define BULK_ARC_OP_USE_SORT(nsrcarcs, ndestarcs) \
759 : : ((nsrcarcs) < 4 ? 0 : ((nsrcarcs) > 32 || (ndestarcs) > 32))
760 : :
761 : : /*
762 : : * moveins - move all in arcs of a state to another state
763 : : *
764 : : * You might think this could be done better by just updating the
765 : : * existing arcs, and you would be right if it weren't for the need
766 : : * for duplicate suppression, which makes it easier to just make new
767 : : * ones to exploit the suppression built into newarc.
768 : : *
769 : : * However, if we have a whole lot of arcs to deal with, retail duplicate
770 : : * checks become too slow. In that case we proceed by sorting and merging
771 : : * the arc lists, and then we can indeed just update the arcs in-place.
772 : : *
773 : : * On the other hand, it's also true that this is frequently called with
774 : : * a brand-new newState that has no existing in-arcs. In that case,
775 : : * de-duplication is unnecessary, so we can just blindly move all the arcs.
776 : : */
777 : : static void
2489 778 : 123895 : moveins(struct nfa *nfa,
779 : : struct state *oldState,
780 : : struct state *newState)
781 : : {
5904 782 [ - + ]: 123895 : assert(oldState != newState);
783 : :
971 784 [ + + ]: 123895 : if (newState->nins == 0)
785 : : {
786 : : /* No need for de-duplication */
787 : : struct arc *a;
788 : :
789 [ + + ]: 101034 : while ((a = oldState->ins) != NULL)
790 : : {
791 : 51889 : createarc(nfa, a->type, a->co, a->from, newState);
792 : 51889 : freearc(nfa, a);
793 : : }
794 : : }
795 [ + + + + : 74750 : else if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins))
+ + ]
7559 bruce@momjian.us 796 : 74704 : {
797 : : /* With not too many arcs, just do them one at a time */
798 : : struct arc *a;
799 : :
3103 tgl@sss.pgh.pa.us 800 [ + + ]: 184522 : while ((a = oldState->ins) != NULL)
801 : : {
802 : 109818 : cparc(nfa, a, a->from, newState);
803 : 109818 : freearc(nfa, a);
804 : : }
805 : : }
806 : : else
807 : : {
808 : : /*
809 : : * With many arcs, use a sort-merge approach. Note changearctarget()
810 : : * will put the arc onto the front of newState's chain, so it does not
811 : : * break our walk through the sorted part of the chain.
812 : : */
813 : : struct arc *oa;
814 : : struct arc *na;
815 : :
816 : : /*
817 : : * Because we bypass newarc() in this code path, we'd better include a
818 : : * cancel check.
819 : : */
372 tmunro@postgresql.or 820 [ - + ]: 46 : INTERRUPT(nfa->v->re);
821 : :
3103 tgl@sss.pgh.pa.us 822 : 46 : sortins(nfa, oldState);
823 : 46 : sortins(nfa, newState);
824 [ - + ]: 46 : if (NISERR())
3103 tgl@sss.pgh.pa.us 825 :UBC 0 : return; /* might have failed to sort */
3103 tgl@sss.pgh.pa.us 826 :CBC 46 : oa = oldState->ins;
827 : 46 : na = newState->ins;
828 [ + + + + ]: 1653 : while (oa != NULL && na != NULL)
829 : : {
830 : 1607 : struct arc *a = oa;
831 : :
832 [ + + + - ]: 1607 : switch (sortins_cmp(&oa, &na))
833 : : {
834 : 83 : case -1:
835 : : /* newState does not have anything matching oa */
836 : 83 : oa = oa->inchain;
837 : :
838 : : /*
839 : : * Rather than doing createarc+freearc, we can just unlink
840 : : * and relink the existing arc struct.
841 : : */
842 : 83 : changearctarget(a, newState);
843 : 83 : break;
844 : 236 : case 0:
845 : : /* match, advance in both lists */
846 : 236 : oa = oa->inchain;
847 : 236 : na = na->inchain;
848 : : /* ... and drop duplicate arc from oldState */
849 : 236 : freearc(nfa, a);
850 : 236 : break;
851 : 1288 : case +1:
852 : : /* advance only na; oa might have a match later */
853 : 1288 : na = na->inchain;
854 : 1288 : break;
3103 tgl@sss.pgh.pa.us 855 :UBC 0 : default:
856 : 0 : assert(NOTREACHED);
857 : : }
858 : : }
3103 tgl@sss.pgh.pa.us 859 [ + + ]:CBC 123 : while (oa != NULL)
860 : : {
861 : : /* newState does not have anything matching oa */
862 : 77 : struct arc *a = oa;
863 : :
864 : 77 : oa = oa->inchain;
865 : 77 : changearctarget(a, newState);
866 : : }
867 : : }
868 : :
5904 869 [ - + ]: 123895 : assert(oldState->nins == 0);
870 [ - + ]: 123895 : assert(oldState->ins == NULL);
871 : : }
872 : :
873 : : /*
874 : : * copyins - copy in arcs of a state to another state
875 : : *
876 : : * The comments for moveins() apply here as well. However, in current
877 : : * usage, this is *only* called with brand-new target states, so that
878 : : * only the "no need for de-duplication" code path is ever reached.
879 : : * We keep the rest #ifdef'd out in case it's needed in the future.
880 : : */
881 : : static void
2489 882 : 9195 : copyins(struct nfa *nfa,
883 : : struct state *oldState,
884 : : struct state *newState)
885 : : {
5904 886 [ - + ]: 9195 : assert(oldState != newState);
971 887 [ - + ]: 9195 : assert(newState->nins == 0); /* see comment above */
888 : :
889 [ + - ]: 9195 : if (newState->nins == 0)
890 : : {
891 : : /* No need for de-duplication */
892 : : struct arc *a;
893 : :
894 [ + + ]: 128998 : for (a = oldState->ins; a != NULL; a = a->inchain)
895 : 119803 : createarc(nfa, a->type, a->co, a->from, newState);
896 : : }
897 : : #ifdef NOT_USED /* see comment above */
898 : : else if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins))
899 : : {
900 : : /* With not too many arcs, just do them one at a time */
901 : : struct arc *a;
902 : :
903 : : for (a = oldState->ins; a != NULL; a = a->inchain)
904 : : cparc(nfa, a, a->from, newState);
905 : : }
906 : : else
907 : : {
908 : : /*
909 : : * With many arcs, use a sort-merge approach. Note that createarc()
910 : : * will put new arcs onto the front of newState's chain, so it does
911 : : * not break our walk through the sorted part of the chain.
912 : : */
913 : : struct arc *oa;
914 : : struct arc *na;
915 : :
916 : : /*
917 : : * Because we bypass newarc() in this code path, we'd better include a
918 : : * cancel check.
919 : : */
920 : : INTERRUPT(nfa->v->re);
921 : :
922 : : sortins(nfa, oldState);
923 : : sortins(nfa, newState);
924 : : if (NISERR())
925 : : return; /* might have failed to sort */
926 : : oa = oldState->ins;
927 : : na = newState->ins;
928 : : while (oa != NULL && na != NULL)
929 : : {
930 : : struct arc *a = oa;
931 : :
932 : : switch (sortins_cmp(&oa, &na))
933 : : {
934 : : case -1:
935 : : /* newState does not have anything matching oa */
936 : : oa = oa->inchain;
937 : : createarc(nfa, a->type, a->co, a->from, newState);
938 : : break;
939 : : case 0:
940 : : /* match, advance in both lists */
941 : : oa = oa->inchain;
942 : : na = na->inchain;
943 : : break;
944 : : case +1:
945 : : /* advance only na; oa might have a match later */
946 : : na = na->inchain;
947 : : break;
948 : : default:
949 : : assert(NOTREACHED);
950 : : }
951 : : }
952 : : while (oa != NULL)
953 : : {
954 : : /* newState does not have anything matching oa */
955 : : struct arc *a = oa;
956 : :
957 : : oa = oa->inchain;
958 : : createarc(nfa, a->type, a->co, a->from, newState);
959 : : }
960 : : }
961 : : #endif /* NOT_USED */
3103 962 : 9195 : }
963 : :
964 : : /*
965 : : * mergeins - merge a list of inarcs into a state
966 : : *
967 : : * This is much like copyins, but the source arcs are listed in an array,
968 : : * and are not guaranteed unique. It's okay to clobber the array contents.
969 : : */
970 : : static void
2489 971 : 126604 : mergeins(struct nfa *nfa,
972 : : struct state *s,
973 : : struct arc **arcarray,
974 : : int arccount)
975 : : {
976 : : struct arc *na;
977 : : int i;
978 : : int j;
979 : :
3103 980 [ + + ]: 126604 : if (arccount <= 0)
981 : 111389 : return;
982 : :
983 : : /*
984 : : * Because we bypass newarc() in this code path, we'd better include a
985 : : * cancel check.
986 : : */
372 tmunro@postgresql.or 987 [ - + ]: 15215 : INTERRUPT(nfa->v->re);
988 : :
989 : : /* Sort existing inarcs as well as proposed new ones */
3103 tgl@sss.pgh.pa.us 990 : 15215 : sortins(nfa, s);
991 [ - + ]: 15215 : if (NISERR())
3103 tgl@sss.pgh.pa.us 992 :UBC 0 : return; /* might have failed to sort */
993 : :
3103 tgl@sss.pgh.pa.us 994 :CBC 15215 : qsort(arcarray, arccount, sizeof(struct arc *), sortins_cmp);
995 : :
996 : : /*
997 : : * arcarray very likely includes dups, so we must eliminate them. (This
998 : : * could be folded into the next loop, but it's not worth the trouble.)
999 : : */
1000 : 15215 : j = 0;
1001 [ + + ]: 7515293 : for (i = 1; i < arccount; i++)
1002 : : {
1003 [ + + - ]: 7500078 : switch (sortins_cmp(&arcarray[j], &arcarray[i]))
1004 : : {
1005 : 7499472 : case -1:
1006 : : /* non-dup */
1007 : 7499472 : arcarray[++j] = arcarray[i];
1008 : 7499472 : break;
1009 : 606 : case 0:
1010 : : /* dup */
1011 : 606 : break;
3103 tgl@sss.pgh.pa.us 1012 :UBC 0 : default:
1013 : : /* trouble */
1014 : 0 : assert(NOTREACHED);
1015 : : }
1016 : : }
3103 tgl@sss.pgh.pa.us 1017 :CBC 15215 : arccount = j + 1;
1018 : :
1019 : : /*
1020 : : * Now merge into s' inchain. Note that createarc() will put new arcs
1021 : : * onto the front of s's chain, so it does not break our walk through the
1022 : : * sorted part of the chain.
1023 : : */
1024 : 15215 : i = 0;
1025 : 15215 : na = s->ins;
1026 [ + + + + ]: 7530101 : while (i < arccount && na != NULL)
1027 : : {
1028 : 7514886 : struct arc *a = arcarray[i];
1029 : :
1030 [ + + + - ]: 7514886 : switch (sortins_cmp(&a, &na))
1031 : : {
1032 : 7493495 : case -1:
1033 : : /* s does not have anything matching a */
1034 : 7493495 : createarc(nfa, a->type, a->co, a->from, s);
1035 : 7493495 : i++;
1036 : 7493495 : break;
1037 : 10 : case 0:
1038 : : /* match, advance in both lists */
1039 : 10 : i++;
1040 : 10 : na = na->inchain;
1041 : 10 : break;
1042 : 21381 : case +1:
1043 : : /* advance only na; array might have a match later */
1044 : 21381 : na = na->inchain;
1045 : 21381 : break;
3103 tgl@sss.pgh.pa.us 1046 :UBC 0 : default:
1047 : 0 : assert(NOTREACHED);
1048 : : }
1049 : : }
3103 tgl@sss.pgh.pa.us 1050 [ + + ]:CBC 36397 : while (i < arccount)
1051 : : {
1052 : : /* s does not have anything matching a */
1053 : 21182 : struct arc *a = arcarray[i];
1054 : :
1055 : 21182 : createarc(nfa, a->type, a->co, a->from, s);
1056 : 21182 : i++;
1057 : : }
1058 : : }
1059 : :
1060 : : /*
1061 : : * moveouts - move all out arcs of a state to another state
1062 : : *
1063 : : * See comments for moveins()
1064 : : */
1065 : : static void
2489 1066 : 34044 : moveouts(struct nfa *nfa,
1067 : : struct state *oldState,
1068 : : struct state *newState)
1069 : : {
5904 1070 [ - + ]: 34044 : assert(oldState != newState);
1071 : :
971 1072 [ + + ]: 34044 : if (newState->nouts == 0)
1073 : : {
1074 : : /* No need for de-duplication */
1075 : : struct arc *a;
1076 : :
1077 [ + + ]: 27412 : while ((a = oldState->outs) != NULL)
1078 : : {
1079 : 14993 : createarc(nfa, a->type, a->co, newState, a->to);
1080 : 14993 : freearc(nfa, a);
1081 : : }
1082 : : }
1083 [ + + + + : 21625 : else if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts))
+ - ]
7559 bruce@momjian.us 1084 : 21617 : {
1085 : : /* With not too many arcs, just do them one at a time */
1086 : : struct arc *a;
1087 : :
3103 tgl@sss.pgh.pa.us 1088 [ + + ]: 52430 : while ((a = oldState->outs) != NULL)
1089 : : {
1090 : 30813 : cparc(nfa, a, newState, a->to);
1091 : 30813 : freearc(nfa, a);
1092 : : }
1093 : : }
1094 : : else
1095 : : {
1096 : : /*
1097 : : * With many arcs, use a sort-merge approach. Note changearcsource()
1098 : : * will put the arc onto the front of newState's chain, so it does not
1099 : : * break our walk through the sorted part of the chain.
1100 : : */
1101 : : struct arc *oa;
1102 : : struct arc *na;
1103 : :
1104 : : /*
1105 : : * Because we bypass newarc() in this code path, we'd better include a
1106 : : * cancel check.
1107 : : */
372 tmunro@postgresql.or 1108 [ - + ]: 8 : INTERRUPT(nfa->v->re);
1109 : :
3103 tgl@sss.pgh.pa.us 1110 : 8 : sortouts(nfa, oldState);
1111 : 8 : sortouts(nfa, newState);
1112 [ - + ]: 8 : if (NISERR())
3103 tgl@sss.pgh.pa.us 1113 :UBC 0 : return; /* might have failed to sort */
3103 tgl@sss.pgh.pa.us 1114 :CBC 8 : oa = oldState->outs;
1115 : 8 : na = newState->outs;
1116 [ + + + + ]: 288 : while (oa != NULL && na != NULL)
1117 : : {
1118 : 280 : struct arc *a = oa;
1119 : :
1120 [ + + + - ]: 280 : switch (sortouts_cmp(&oa, &na))
1121 : : {
1122 : 258 : case -1:
1123 : : /* newState does not have anything matching oa */
1124 : 258 : oa = oa->outchain;
1125 : :
1126 : : /*
1127 : : * Rather than doing createarc+freearc, we can just unlink
1128 : : * and relink the existing arc struct.
1129 : : */
1143 1130 : 258 : changearcsource(a, newState);
3103 1131 : 258 : break;
1132 : 14 : case 0:
1133 : : /* match, advance in both lists */
1134 : 14 : oa = oa->outchain;
1135 : 14 : na = na->outchain;
1136 : : /* ... and drop duplicate arc from oldState */
1137 : 14 : freearc(nfa, a);
1138 : 14 : break;
1139 : 8 : case +1:
1140 : : /* advance only na; oa might have a match later */
1141 : 8 : na = na->outchain;
1142 : 8 : break;
3103 tgl@sss.pgh.pa.us 1143 :UBC 0 : default:
1144 : 0 : assert(NOTREACHED);
1145 : : }
1146 : : }
3103 tgl@sss.pgh.pa.us 1147 [ + + ]:CBC 44 : while (oa != NULL)
1148 : : {
1149 : : /* newState does not have anything matching oa */
1150 : 36 : struct arc *a = oa;
1151 : :
1152 : 36 : oa = oa->outchain;
1143 1153 : 36 : changearcsource(a, newState);
1154 : : }
1155 : : }
1156 : :
3103 1157 [ - + ]: 34044 : assert(oldState->nouts == 0);
1158 [ - + ]: 34044 : assert(oldState->outs == NULL);
1159 : : }
1160 : :
1161 : : /*
1162 : : * copyouts - copy out arcs of a state to another state
1163 : : *
1164 : : * See comments for copyins()
1165 : : */
1166 : : static void
2489 1167 : 6895 : copyouts(struct nfa *nfa,
1168 : : struct state *oldState,
1169 : : struct state *newState)
1170 : : {
5904 1171 [ - + ]: 6895 : assert(oldState != newState);
971 1172 [ - + ]: 6895 : assert(newState->nouts == 0); /* see comment above */
1173 : :
1174 [ + - ]: 6895 : if (newState->nouts == 0)
1175 : : {
1176 : : /* No need for de-duplication */
1177 : : struct arc *a;
1178 : :
1179 [ + + ]: 243068 : for (a = oldState->outs; a != NULL; a = a->outchain)
1180 : 236173 : createarc(nfa, a->type, a->co, newState, a->to);
1181 : : }
1182 : : #ifdef NOT_USED /* see comment above */
1183 : : else if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts))
1184 : : {
1185 : : /* With not too many arcs, just do them one at a time */
1186 : : struct arc *a;
1187 : :
1188 : : for (a = oldState->outs; a != NULL; a = a->outchain)
1189 : : cparc(nfa, a, newState, a->to);
1190 : : }
1191 : : else
1192 : : {
1193 : : /*
1194 : : * With many arcs, use a sort-merge approach. Note that createarc()
1195 : : * will put new arcs onto the front of newState's chain, so it does
1196 : : * not break our walk through the sorted part of the chain.
1197 : : */
1198 : : struct arc *oa;
1199 : : struct arc *na;
1200 : :
1201 : : /*
1202 : : * Because we bypass newarc() in this code path, we'd better include a
1203 : : * cancel check.
1204 : : */
1205 : : INTERRUPT(nfa->v->re);
1206 : :
1207 : : sortouts(nfa, oldState);
1208 : : sortouts(nfa, newState);
1209 : : if (NISERR())
1210 : : return; /* might have failed to sort */
1211 : : oa = oldState->outs;
1212 : : na = newState->outs;
1213 : : while (oa != NULL && na != NULL)
1214 : : {
1215 : : struct arc *a = oa;
1216 : :
1217 : : switch (sortouts_cmp(&oa, &na))
1218 : : {
1219 : : case -1:
1220 : : /* newState does not have anything matching oa */
1221 : : oa = oa->outchain;
1222 : : createarc(nfa, a->type, a->co, newState, a->to);
1223 : : break;
1224 : : case 0:
1225 : : /* match, advance in both lists */
1226 : : oa = oa->outchain;
1227 : : na = na->outchain;
1228 : : break;
1229 : : case +1:
1230 : : /* advance only na; oa might have a match later */
1231 : : na = na->outchain;
1232 : : break;
1233 : : default:
1234 : : assert(NOTREACHED);
1235 : : }
1236 : : }
1237 : : while (oa != NULL)
1238 : : {
1239 : : /* newState does not have anything matching oa */
1240 : : struct arc *a = oa;
1241 : :
1242 : : oa = oa->outchain;
1243 : : createarc(nfa, a->type, a->co, newState, a->to);
1244 : : }
1245 : : }
1246 : : #endif /* NOT_USED */
7739 1247 : 6895 : }
1248 : :
1249 : : /*
1250 : : * cloneouts - copy out arcs of a state to another state pair, modifying type
1251 : : *
1252 : : * This is only used to convert PLAIN arcs to AHEAD/BEHIND arcs, which share
1253 : : * the same interpretation of "co". It wouldn't be sensible with LACONs.
1254 : : */
1255 : : static void
2489 1256 : 171 : cloneouts(struct nfa *nfa,
1257 : : struct state *old,
1258 : : struct state *from,
1259 : : struct state *to,
1260 : : int type)
1261 : : {
1262 : : struct arc *a;
1263 : :
7739 1264 [ - + ]: 171 : assert(old != from);
1149 1265 [ + + - + ]: 171 : assert(type == AHEAD || type == BEHIND);
1266 : :
7739 1267 [ + + ]: 595 : for (a = old->outs; a != NULL; a = a->outchain)
1268 : : {
1149 1269 [ - + ]: 424 : assert(a->type == PLAIN);
7739 1270 : 424 : newarc(nfa, type, a->co, from, to);
1271 : : }
1272 : 171 : }
1273 : :
1274 : : /*
1275 : : * delsub - delete a sub-NFA, updating subre pointers if necessary
1276 : : *
1277 : : * This uses a recursive traversal of the sub-NFA, marking already-seen
1278 : : * states using their tmp pointer.
1279 : : */
1280 : : static void
2489 1281 : 4774 : delsub(struct nfa *nfa,
1282 : : struct state *lp, /* the sub-NFA goes from here... */
1283 : : struct state *rp) /* ...to here, *not* inclusive */
1284 : : {
7739 1285 [ - + ]: 4774 : assert(lp != rp);
1286 : :
7559 bruce@momjian.us 1287 : 4774 : rp->tmp = rp; /* mark end */
1288 : :
7739 tgl@sss.pgh.pa.us 1289 : 4774 : deltraverse(nfa, lp, lp);
3117 1290 [ - + ]: 4774 : if (NISERR())
3117 tgl@sss.pgh.pa.us 1291 :UBC 0 : return; /* asserts might not hold after failure */
7739 tgl@sss.pgh.pa.us 1292 [ + - - + ]:CBC 4774 : assert(lp->nouts == 0 && rp->nins == 0); /* did the job */
7559 bruce@momjian.us 1293 [ + - - + ]: 4774 : assert(lp->no != FREESTATE && rp->no != FREESTATE); /* no more */
1294 : :
1295 : 4774 : rp->tmp = NULL; /* unmark end */
1296 : 4774 : lp->tmp = NULL; /* and begin, marked by deltraverse */
1297 : : }
1298 : :
1299 : : /*
1300 : : * deltraverse - the recursive heart of delsub
1301 : : * This routine's basic job is to destroy all out-arcs of the state.
1302 : : */
1303 : : static void
2489 tgl@sss.pgh.pa.us 1304 : 13999 : deltraverse(struct nfa *nfa,
1305 : : struct state *leftend,
1306 : : struct state *s)
1307 : : {
1308 : : struct arc *a;
1309 : : struct state *to;
1310 : :
1311 : : /* Since this is recursive, it could be driven to stack overflow */
3117 1312 [ - + ]: 13999 : if (STACK_TOO_DEEP(nfa->v->re))
1313 : : {
3117 tgl@sss.pgh.pa.us 1314 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
1315 : 0 : return;
1316 : : }
1317 : :
7739 tgl@sss.pgh.pa.us 1318 [ + + ]:CBC 13999 : if (s->nouts == 0)
7559 bruce@momjian.us 1319 : 101 : return; /* nothing to do */
7739 tgl@sss.pgh.pa.us 1320 [ + + ]: 13898 : if (s->tmp != NULL)
7559 bruce@momjian.us 1321 : 4688 : return; /* already in progress */
1322 : :
1323 : 9210 : s->tmp = s; /* mark as in progress */
1324 : :
1325 [ + + ]: 18435 : while ((a = s->outs) != NULL)
1326 : : {
7739 tgl@sss.pgh.pa.us 1327 : 9225 : to = a->to;
1328 : 9225 : deltraverse(nfa, leftend, to);
3117 1329 [ - + ]: 9225 : if (NISERR())
3117 tgl@sss.pgh.pa.us 1330 :UBC 0 : return; /* asserts might not hold after failure */
7739 tgl@sss.pgh.pa.us 1331 [ + + - + ]:CBC 9225 : assert(to->nouts == 0 || to->tmp != NULL);
1332 : 9225 : freearc(nfa, a);
7559 bruce@momjian.us 1333 [ + + + + ]: 9225 : if (to->nins == 0 && to->tmp == NULL)
1334 : : {
7739 tgl@sss.pgh.pa.us 1335 [ - + ]: 4436 : assert(to->nouts == 0);
1336 : 4436 : freestate(nfa, to);
1337 : : }
1338 : : }
1339 : :
7559 bruce@momjian.us 1340 [ - + ]: 9210 : assert(s->no != FREESTATE); /* we're still here */
2489 tgl@sss.pgh.pa.us 1341 [ + + - + ]: 9210 : assert(s == leftend || s->nins != 0); /* and still reachable */
7739 1342 [ - + ]: 9210 : assert(s->nouts == 0); /* but have no outarcs */
1343 : :
7559 bruce@momjian.us 1344 : 9210 : s->tmp = NULL; /* we're done here */
1345 : : }
1346 : :
1347 : : /*
1348 : : * dupnfa - duplicate sub-NFA
1349 : : *
1350 : : * Another recursive traversal, this time using tmp to point to duplicates
1351 : : * as well as mark already-seen states. (You knew there was a reason why
1352 : : * it's a state pointer, didn't you? :-))
1353 : : */
1354 : : static void
2489 tgl@sss.pgh.pa.us 1355 : 6954 : dupnfa(struct nfa *nfa,
1356 : : struct state *start, /* duplicate of subNFA starting here */
1357 : : struct state *stop, /* and stopping here */
1358 : : struct state *from, /* stringing duplicate from here */
1359 : : struct state *to) /* to here */
1360 : : {
7559 bruce@momjian.us 1361 [ - + ]: 6954 : if (start == stop)
1362 : : {
7739 tgl@sss.pgh.pa.us 1363 :UBC 0 : newarc(nfa, EMPTY, 0, from, to);
1364 : 0 : return;
1365 : : }
1366 : :
7739 tgl@sss.pgh.pa.us 1367 :CBC 6954 : stop->tmp = to;
1368 : 6954 : duptraverse(nfa, start, from);
1369 : : /* done, except for clearing out the tmp pointers */
1370 : :
1371 : 6954 : stop->tmp = NULL;
1372 : 6954 : cleartraverse(nfa, start);
1373 : : }
1374 : :
1375 : : /*
1376 : : * duptraverse - recursive heart of dupnfa
1377 : : */
1378 : : static void
2489 1379 : 184717 : duptraverse(struct nfa *nfa,
1380 : : struct state *s,
1381 : : struct state *stmp) /* s's duplicate, or NULL */
1382 : : {
1383 : : struct arc *a;
1384 : :
1385 : : /* Since this is recursive, it could be driven to stack overflow */
3117 1386 [ - + ]: 184717 : if (STACK_TOO_DEEP(nfa->v->re))
1387 : : {
3117 tgl@sss.pgh.pa.us 1388 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
1389 : 0 : return;
1390 : : }
1391 : :
7739 tgl@sss.pgh.pa.us 1392 [ + + ]:CBC 184717 : if (s->tmp != NULL)
7559 bruce@momjian.us 1393 : 58201 : return; /* already done */
1394 : :
7739 tgl@sss.pgh.pa.us 1395 [ + + ]: 126516 : s->tmp = (stmp == NULL) ? newstate(nfa) : stmp;
7559 bruce@momjian.us 1396 [ - + ]: 126516 : if (s->tmp == NULL)
1397 : : {
7739 tgl@sss.pgh.pa.us 1398 [ # # ]:UBC 0 : assert(NISERR());
1399 : 0 : return;
1400 : : }
1401 : :
7559 bruce@momjian.us 1402 [ + + + - ]:CBC 304279 : for (a = s->outs; a != NULL && !NISERR(); a = a->outchain)
1403 : : {
1404 : 177763 : duptraverse(nfa, a->to, (struct state *) NULL);
5946 tgl@sss.pgh.pa.us 1405 [ - + ]: 177763 : if (NISERR())
5946 tgl@sss.pgh.pa.us 1406 :UBC 0 : break;
7739 tgl@sss.pgh.pa.us 1407 [ - + ]:CBC 177763 : assert(a->to->tmp != NULL);
1408 : 177763 : cparc(nfa, a, s->tmp, a->to->tmp);
1409 : : }
1410 : : }
1411 : :
1412 : : /*
1413 : : * removeconstraints - remove any constraints in an NFA
1414 : : *
1415 : : * Constraint arcs are replaced by empty arcs, essentially treating all
1416 : : * constraints as automatically satisfied.
1417 : : */
1418 : : static void
1139 1419 : 101 : removeconstraints(struct nfa *nfa,
1420 : : struct state *start, /* process subNFA starting here */
1421 : : struct state *stop) /* and stopping here */
1422 : : {
1423 [ - + ]: 101 : if (start == stop)
1139 tgl@sss.pgh.pa.us 1424 :UBC 0 : return;
1425 : :
1139 tgl@sss.pgh.pa.us 1426 :CBC 101 : stop->tmp = stop;
1427 : 101 : removetraverse(nfa, start);
1428 : : /* done, except for clearing out the tmp pointers */
1429 : :
1430 : 101 : stop->tmp = NULL;
1431 : 101 : cleartraverse(nfa, start);
1432 : : }
1433 : :
1434 : : /*
1435 : : * removetraverse - recursive heart of removeconstraints
1436 : : */
1437 : : static void
1438 : 281 : removetraverse(struct nfa *nfa,
1439 : : struct state *s)
1440 : : {
1441 : : struct arc *a;
1442 : : struct arc *oa;
1443 : :
1444 : : /* Since this is recursive, it could be driven to stack overflow */
1445 [ - + ]: 281 : if (STACK_TOO_DEEP(nfa->v->re))
1446 : : {
1139 tgl@sss.pgh.pa.us 1447 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
1448 : 0 : return;
1449 : : }
1450 : :
1139 tgl@sss.pgh.pa.us 1451 [ + + ]:CBC 281 : if (s->tmp != NULL)
1452 : 126 : return; /* already done */
1453 : :
1454 : 155 : s->tmp = s;
1455 [ + + + - ]: 335 : for (a = s->outs; a != NULL && !NISERR(); a = oa)
1456 : : {
1457 : 180 : removetraverse(nfa, a->to);
1458 [ - + ]: 180 : if (NISERR())
1139 tgl@sss.pgh.pa.us 1459 :UBC 0 : break;
1139 tgl@sss.pgh.pa.us 1460 :CBC 180 : oa = a->outchain;
1461 [ + + - ]: 180 : switch (a->type)
1462 : : {
1463 : 173 : case PLAIN:
1464 : : case EMPTY:
1465 : : /* nothing to do */
1466 : 173 : break;
1467 : 7 : case AHEAD:
1468 : : case BEHIND:
1469 : : case '^':
1470 : : case '$':
1471 : : case LACON:
1472 : : /* replace it */
1473 : 7 : newarc(nfa, EMPTY, 0, s, a->to);
1474 : 7 : freearc(nfa, a);
1475 : 7 : break;
1139 tgl@sss.pgh.pa.us 1476 :UBC 0 : default:
1477 [ # # ]: 0 : NERR(REG_ASSERT);
1478 : 0 : break;
1479 : : }
1480 : : }
1481 : : }
1482 : :
1483 : : /*
1484 : : * cleartraverse - recursive cleanup for algorithms that leave tmp ptrs set
1485 : : */
1486 : : static void
2489 tgl@sss.pgh.pa.us 1487 :CBC 1048388 : cleartraverse(struct nfa *nfa,
1488 : : struct state *s)
1489 : : {
1490 : : struct arc *a;
1491 : :
1492 : : /* Since this is recursive, it could be driven to stack overflow */
3117 1493 [ - + ]: 1048388 : if (STACK_TOO_DEEP(nfa->v->re))
1494 : : {
3117 tgl@sss.pgh.pa.us 1495 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
1496 : 0 : return;
1497 : : }
1498 : :
7739 tgl@sss.pgh.pa.us 1499 [ + + ]:CBC 1048388 : if (s->tmp == NULL)
1500 : 611135 : return;
1501 : 437253 : s->tmp = NULL;
1502 : :
1503 [ + + ]: 1460817 : for (a = s->outs; a != NULL; a = a->outchain)
1504 : 1023564 : cleartraverse(nfa, a->to);
1505 : : }
1506 : :
1507 : : /*
1508 : : * single_color_transition - does getting from s1 to s2 cross one PLAIN arc?
1509 : : *
1510 : : * If traversing from s1 to s2 requires a single PLAIN match (possibly of any
1511 : : * of a set of colors), return a state whose outarc list contains only PLAIN
1512 : : * arcs of those color(s). Otherwise return NULL.
1513 : : *
1514 : : * This is used before optimizing the NFA, so there may be EMPTY arcs, which
1515 : : * we should ignore; the possibility of an EMPTY is why the result state could
1516 : : * be different from s1.
1517 : : *
1518 : : * It's worth troubling to handle multiple parallel PLAIN arcs here because a
1519 : : * bracket construct such as [abc] might yield either one or several parallel
1520 : : * PLAIN arcs depending on earlier atoms in the expression. We'd rather that
1521 : : * that implementation detail not create user-visible performance differences.
1522 : : */
1523 : : static struct state *
2489 1524 : 127 : single_color_transition(struct state *s1, struct state *s2)
1525 : : {
1526 : : struct arc *a;
1527 : :
1528 : : /* Ignore leading EMPTY arc, if any */
3089 1529 [ + - + - ]: 127 : if (s1->nouts == 1 && s1->outs->type == EMPTY)
1530 : 127 : s1 = s1->outs->to;
1531 : : /* Likewise for any trailing EMPTY arc */
1532 [ + - + - ]: 127 : if (s2->nins == 1 && s2->ins->type == EMPTY)
1533 : 127 : s2 = s2->ins->from;
1534 : : /* Perhaps we could have a single-state loop in between, if so reject */
1535 [ - + ]: 127 : if (s1 == s2)
3089 tgl@sss.pgh.pa.us 1536 :UBC 0 : return NULL;
1537 : : /* s1 must have at least one outarc... */
3089 tgl@sss.pgh.pa.us 1538 [ - + ]:CBC 127 : if (s1->outs == NULL)
3089 tgl@sss.pgh.pa.us 1539 :UBC 0 : return NULL;
1540 : : /* ... and they must all be PLAIN arcs to s2 */
3089 tgl@sss.pgh.pa.us 1541 [ + + ]:CBC 218 : for (a = s1->outs; a != NULL; a = a->outchain)
1542 : : {
1543 [ + + + + ]: 134 : if (a->type != PLAIN || a->to != s2)
1544 : 43 : return NULL;
1545 : : }
1546 : : /* OK, return s1 as the possessor of the relevant outarcs */
1547 : 84 : return s1;
1548 : : }
1549 : :
1550 : : /*
1551 : : * specialcolors - fill in special colors for an NFA
1552 : : */
1553 : : static void
2489 1554 : 8889 : specialcolors(struct nfa *nfa)
1555 : : {
1556 : : /* false colors for BOS, BOL, EOS, EOL */
7559 bruce@momjian.us 1557 [ + + ]: 8889 : if (nfa->parent == NULL)
1558 : : {
7739 tgl@sss.pgh.pa.us 1559 : 3491 : nfa->bos[0] = pseudocolor(nfa->cm);
1560 : 3491 : nfa->bos[1] = pseudocolor(nfa->cm);
1561 : 3491 : nfa->eos[0] = pseudocolor(nfa->cm);
1562 : 3491 : nfa->eos[1] = pseudocolor(nfa->cm);
1563 : : }
1564 : : else
1565 : : {
1566 [ - + ]: 5398 : assert(nfa->parent->bos[0] != COLORLESS);
1567 : 5398 : nfa->bos[0] = nfa->parent->bos[0];
1568 [ - + ]: 5398 : assert(nfa->parent->bos[1] != COLORLESS);
1569 : 5398 : nfa->bos[1] = nfa->parent->bos[1];
1570 [ - + ]: 5398 : assert(nfa->parent->eos[0] != COLORLESS);
1571 : 5398 : nfa->eos[0] = nfa->parent->eos[0];
1572 [ - + ]: 5398 : assert(nfa->parent->eos[1] != COLORLESS);
1573 : 5398 : nfa->eos[1] = nfa->parent->eos[1];
1574 : : }
1575 : 8889 : }
1576 : :
1577 : : /*
1578 : : * optimize - optimize an NFA
1579 : : *
1580 : : * The main goal of this function is not so much "optimization" (though it
1581 : : * does try to get rid of useless NFA states) as reducing the NFA to a form
1582 : : * the regex executor can handle. The executor, and indeed the cNFA format
1583 : : * that is its input, can only handle PLAIN and LACON arcs. The output of
1584 : : * the regex parser also includes EMPTY (do-nothing) arcs, as well as
1585 : : * ^, $, AHEAD, and BEHIND constraint arcs, which we must get rid of here.
1586 : : * We first get rid of EMPTY arcs and then deal with the constraint arcs.
1587 : : * The hardest part of either job is to get rid of circular loops of the
1588 : : * target arc type. We would have to do that in any case, though, as such a
1589 : : * loop would otherwise allow the executor to cycle through the loop endlessly
1590 : : * without making any progress in the input string.
1591 : : */
1592 : : static long /* re_info bits */
2489 1593 : 8886 : optimize(struct nfa *nfa,
1594 : : FILE *f) /* for debug output; NULL none */
1595 : : {
1596 : : #ifdef REG_DEBUG
1597 : : int verbose = (f != NULL) ? 1 : 0;
1598 : :
1599 : : if (verbose)
1600 : : fprintf(f, "\ninitial cleanup:\n");
1601 : : #endif
7559 bruce@momjian.us 1602 : 8886 : cleanup(nfa); /* may simplify situation */
1603 : : #ifdef REG_DEBUG
1604 : : if (verbose)
1605 : : dumpnfa(nfa, f);
1606 : : if (verbose)
1607 : : fprintf(f, "\nempties:\n");
1608 : : #endif
1609 : 8886 : fixempties(nfa, f); /* get rid of EMPTY arcs */
1610 : : #ifdef REG_DEBUG
1611 : : if (verbose)
1612 : : fprintf(f, "\nconstraints:\n");
1613 : : #endif
3103 tgl@sss.pgh.pa.us 1614 : 8886 : fixconstraintloops(nfa, f); /* get rid of constraint loops */
7559 bruce@momjian.us 1615 : 8886 : pullback(nfa, f); /* pull back constraints backward */
1616 : 8886 : pushfwd(nfa, f); /* push fwd constraints forward */
1617 : : #ifdef REG_DEBUG
1618 : : if (verbose)
1619 : : fprintf(f, "\nfinal cleanup:\n");
1620 : : #endif
1621 : 8886 : cleanup(nfa); /* final tidying */
1622 : : #ifdef REG_DEBUG
1623 : : if (verbose)
1624 : : dumpnfa(nfa, f);
1625 : : #endif
1626 : 8886 : return analyze(nfa); /* and analysis */
1627 : : }
1628 : :
1629 : : /*
1630 : : * pullback - pull back constraints backward to eliminate them
1631 : : */
1632 : : static void
2489 tgl@sss.pgh.pa.us 1633 : 8886 : pullback(struct nfa *nfa,
1634 : : FILE *f) /* for debug output; NULL none */
1635 : : {
1636 : : struct state *s;
1637 : : struct state *nexts;
1638 : : struct arc *a;
1639 : : struct arc *nexta;
1640 : : struct state *intermediates;
1641 : : int progress;
1642 : :
1643 : : /* find and pull until there are no more */
1644 : : do
1645 : : {
7739 1646 : 13838 : progress = 0;
7559 bruce@momjian.us 1647 [ + + + + ]: 216961 : for (s = nfa->states; s != NULL && !NISERR(); s = nexts)
1648 : : {
7739 tgl@sss.pgh.pa.us 1649 : 203123 : nexts = s->next;
3103 1650 : 203123 : intermediates = NULL;
7559 bruce@momjian.us 1651 [ + + + - ]: 917973 : for (a = s->outs; a != NULL && !NISERR(); a = nexta)
1652 : : {
7739 tgl@sss.pgh.pa.us 1653 : 714850 : nexta = a->outchain;
1654 [ + + + + ]: 714850 : if (a->type == '^' || a->type == BEHIND)
3103 1655 [ + + ]: 46861 : if (pull(nfa, a, &intermediates))
7739 1656 : 18337 : progress = 1;
1657 : : }
1658 : : /* clear tmp fields of intermediate states created here */
3103 1659 [ + + ]: 204349 : while (intermediates != NULL)
1660 : : {
1661 : 1226 : struct state *ns = intermediates->tmp;
1662 : :
1663 : 1226 : intermediates->tmp = NULL;
1664 : 1226 : intermediates = ns;
1665 : : }
1666 : : /* if s is now useless, get rid of it */
1667 [ + + + + : 203123 : if ((s->nins == 0 || s->nouts == 0) && !s->flag)
+ + ]
1668 : 15729 : dropstate(nfa, s);
1669 : : }
7739 1670 [ + + - + ]: 13838 : if (progress && f != NULL)
7739 tgl@sss.pgh.pa.us 1671 :UBC 0 : dumpnfa(nfa, f);
7739 tgl@sss.pgh.pa.us 1672 [ + + + - ]:CBC 13838 : } while (progress && !NISERR());
1673 [ + + ]: 8886 : if (NISERR())
1674 : 3 : return;
1675 : :
1676 : : /*
1677 : : * Any ^ constraints we were able to pull to the start state can now be
1678 : : * replaced by PLAIN arcs referencing the BOS or BOL colors. There should
1679 : : * be no other ^ or BEHIND arcs left in the NFA, though we do not check
1680 : : * that here (compact() will fail if so).
1681 : : */
7559 bruce@momjian.us 1682 [ + + ]: 34455 : for (a = nfa->pre->outs; a != NULL; a = nexta)
1683 : : {
7739 tgl@sss.pgh.pa.us 1684 : 25572 : nexta = a->outchain;
7559 bruce@momjian.us 1685 [ + + ]: 25572 : if (a->type == '^')
1686 : : {
7739 tgl@sss.pgh.pa.us 1687 [ + + - + ]: 18308 : assert(a->co == 0 || a->co == 1);
1688 : 18308 : newarc(nfa, PLAIN, nfa->bos[a->co], a->from, a->to);
1689 : 18308 : freearc(nfa, a);
1690 : : }
1691 : : }
1692 : : }
1693 : :
1694 : : /*
1695 : : * pull - pull a back constraint backward past its source state
1696 : : *
1697 : : * Returns 1 if successful (which it always is unless the source is the
1698 : : * start state or we have an internal error), 0 if nothing happened.
1699 : : *
1700 : : * A significant property of this function is that it deletes no pre-existing
1701 : : * states, and no outarcs of the constraint's from state other than the given
1702 : : * constraint arc. This makes the loops in pullback() safe, at the cost that
1703 : : * we may leave useless states behind. Therefore, we leave it to pullback()
1704 : : * to delete such states.
1705 : : *
1706 : : * If the from state has multiple back-constraint outarcs, and/or multiple
1707 : : * compatible constraint inarcs, we only need to create one new intermediate
1708 : : * state per combination of predecessor and successor states. *intermediates
1709 : : * points to a list of such intermediate states for this from state (chained
1710 : : * through their tmp fields).
1711 : : */
1712 : : static int
2489 1713 : 46861 : pull(struct nfa *nfa,
1714 : : struct arc *con,
1715 : : struct state **intermediates)
1716 : : {
7739 1717 : 46861 : struct state *from = con->from;
1718 : 46861 : struct state *to = con->to;
1719 : : struct arc *a;
1720 : : struct arc *nexta;
1721 : : struct state *s;
1722 : :
3103 1723 [ - + ]: 46861 : assert(from != to); /* should have gotten rid of this earlier */
7559 bruce@momjian.us 1724 [ + + ]: 46861 : if (from->flag) /* can't pull back beyond start */
7739 tgl@sss.pgh.pa.us 1725 : 28524 : return 0;
7559 bruce@momjian.us 1726 [ + + ]: 18337 : if (from->nins == 0)
1727 : : { /* unreachable */
7739 tgl@sss.pgh.pa.us 1728 : 3652 : freearc(nfa, con);
1729 : 3652 : return 1;
1730 : : }
1731 : :
1732 : : /*
1733 : : * First, clone from state if necessary to avoid other outarcs. This may
1734 : : * seem wasteful, but it simplifies the logic, and we'll get rid of the
1735 : : * clone state again at the bottom.
1736 : : */
7559 bruce@momjian.us 1737 [ + + ]: 14685 : if (from->nouts > 1)
1738 : : {
7739 tgl@sss.pgh.pa.us 1739 : 9195 : s = newstate(nfa);
1740 [ - + ]: 9195 : if (NISERR())
7739 tgl@sss.pgh.pa.us 1741 :UBC 0 : return 0;
3103 tgl@sss.pgh.pa.us 1742 :CBC 9195 : copyins(nfa, from, s); /* duplicate inarcs */
7559 bruce@momjian.us 1743 : 9195 : cparc(nfa, con, s, to); /* move constraint arc */
7739 tgl@sss.pgh.pa.us 1744 : 9195 : freearc(nfa, con);
3103 1745 [ - + ]: 9195 : if (NISERR())
3103 tgl@sss.pgh.pa.us 1746 :UBC 0 : return 0;
7739 tgl@sss.pgh.pa.us 1747 :CBC 9195 : from = s;
1748 : 9195 : con = from->outs;
1749 : : }
1750 [ - + ]: 14685 : assert(from->nouts == 1);
1751 : :
1752 : : /* propagate the constraint into the from state's inarcs */
3103 1753 [ + + + - ]: 154974 : for (a = from->ins; a != NULL && !NISERR(); a = nexta)
1754 : : {
7739 1755 : 140289 : nexta = a->inchain;
1149 1756 [ + + + + : 140289 : switch (combine(nfa, con, a))
- ]
1757 : : {
7559 bruce@momjian.us 1758 : 41914 : case INCOMPATIBLE: /* destroy the arc */
1759 : 41914 : freearc(nfa, a);
1760 : 41914 : break;
1761 : 7768 : case SATISFIED: /* no action needed */
1762 : 7768 : break;
1763 : 89843 : case COMPATIBLE: /* swap the two arcs, more or less */
1764 : : /* need an intermediate state, but might have one already */
3103 tgl@sss.pgh.pa.us 1765 [ + + ]: 101636 : for (s = *intermediates; s != NULL; s = s->tmp)
1766 : : {
1767 [ + - - + ]: 100410 : assert(s->nins > 0 && s->nouts > 0);
1768 [ + + + + ]: 100410 : if (s->ins->from == a->from && s->outs->to == to)
1769 : 88617 : break;
1770 : : }
1771 [ + + ]: 89843 : if (s == NULL)
1772 : : {
1773 : 1226 : s = newstate(nfa);
1774 [ - + ]: 1226 : if (NISERR())
3103 tgl@sss.pgh.pa.us 1775 :UBC 0 : return 0;
3103 tgl@sss.pgh.pa.us 1776 :CBC 1226 : s->tmp = *intermediates;
1777 : 1226 : *intermediates = s;
1778 : : }
7559 bruce@momjian.us 1779 : 89843 : cparc(nfa, con, a->from, s);
3103 tgl@sss.pgh.pa.us 1780 : 89843 : cparc(nfa, a, s, to);
7559 bruce@momjian.us 1781 : 89843 : freearc(nfa, a);
1782 : 89843 : break;
1149 tgl@sss.pgh.pa.us 1783 : 764 : case REPLACEARC: /* replace arc's color */
1784 : 764 : newarc(nfa, a->type, con->co, a->from, to);
1785 : 764 : freearc(nfa, a);
1786 : 764 : break;
7559 bruce@momjian.us 1787 :UBC 0 : default:
1788 : 0 : assert(NOTREACHED);
1789 : : break;
1790 : : }
1791 : : }
1792 : :
1793 : : /* remaining inarcs, if any, incorporate the constraint */
7739 tgl@sss.pgh.pa.us 1794 :CBC 14685 : moveins(nfa, from, to);
3103 1795 : 14685 : freearc(nfa, con);
1796 : : /* from state is now useless, but we leave it to pullback() to clean up */
7739 1797 : 14685 : return 1;
1798 : : }
1799 : :
1800 : : /*
1801 : : * pushfwd - push forward constraints forward to eliminate them
1802 : : */
1803 : : static void
2489 1804 : 8886 : pushfwd(struct nfa *nfa,
1805 : : FILE *f) /* for debug output; NULL none */
1806 : : {
1807 : : struct state *s;
1808 : : struct state *nexts;
1809 : : struct arc *a;
1810 : : struct arc *nexta;
1811 : : struct state *intermediates;
1812 : : int progress;
1813 : :
1814 : : /* find and push until there are no more */
1815 : : do
1816 : : {
7739 1817 : 13353 : progress = 0;
7559 bruce@momjian.us 1818 [ + + + + ]: 190030 : for (s = nfa->states; s != NULL && !NISERR(); s = nexts)
1819 : : {
7739 tgl@sss.pgh.pa.us 1820 : 176677 : nexts = s->next;
3103 1821 : 176677 : intermediates = NULL;
7559 bruce@momjian.us 1822 [ + + + - ]: 820046 : for (a = s->ins; a != NULL && !NISERR(); a = nexta)
1823 : : {
7739 tgl@sss.pgh.pa.us 1824 : 643369 : nexta = a->inchain;
1825 [ + + + + ]: 643369 : if (a->type == '$' || a->type == AHEAD)
3103 1826 [ + + ]: 33423 : if (push(nfa, a, &intermediates))
7739 1827 : 10547 : progress = 1;
1828 : : }
1829 : : /* clear tmp fields of intermediate states created here */
3103 1830 [ + + ]: 176679 : while (intermediates != NULL)
1831 : : {
1832 : 2 : struct state *ns = intermediates->tmp;
1833 : :
1834 : 2 : intermediates->tmp = NULL;
1835 : 2 : intermediates = ns;
1836 : : }
1837 : : /* if s is now useless, get rid of it */
1838 [ + + + + : 176677 : if ((s->nins == 0 || s->nouts == 0) && !s->flag)
+ + ]
1839 : 10827 : dropstate(nfa, s);
1840 : : }
7739 1841 [ + + - + ]: 13353 : if (progress && f != NULL)
7739 tgl@sss.pgh.pa.us 1842 :UBC 0 : dumpnfa(nfa, f);
7739 tgl@sss.pgh.pa.us 1843 [ + + + - ]:CBC 13353 : } while (progress && !NISERR());
1844 [ + + ]: 8886 : if (NISERR())
1845 : 3 : return;
1846 : :
1847 : : /*
1848 : : * Any $ constraints we were able to push to the post state can now be
1849 : : * replaced by PLAIN arcs referencing the EOS or EOL colors. There should
1850 : : * be no other $ or AHEAD arcs left in the NFA, though we do not check
1851 : : * that here (compact() will fail if so).
1852 : : */
7559 bruce@momjian.us 1853 [ + + ]: 27813 : for (a = nfa->post->ins; a != NULL; a = nexta)
1854 : : {
7739 tgl@sss.pgh.pa.us 1855 : 18930 : nexta = a->inchain;
7559 bruce@momjian.us 1856 [ + + ]: 18930 : if (a->type == '$')
1857 : : {
7739 tgl@sss.pgh.pa.us 1858 [ + + - + ]: 13554 : assert(a->co == 0 || a->co == 1);
1859 : 13554 : newarc(nfa, PLAIN, nfa->eos[a->co], a->from, a->to);
1860 : 13554 : freearc(nfa, a);
1861 : : }
1862 : : }
1863 : : }
1864 : :
1865 : : /*
1866 : : * push - push a forward constraint forward past its destination state
1867 : : *
1868 : : * Returns 1 if successful (which it always is unless the destination is the
1869 : : * post state or we have an internal error), 0 if nothing happened.
1870 : : *
1871 : : * A significant property of this function is that it deletes no pre-existing
1872 : : * states, and no inarcs of the constraint's to state other than the given
1873 : : * constraint arc. This makes the loops in pushfwd() safe, at the cost that
1874 : : * we may leave useless states behind. Therefore, we leave it to pushfwd()
1875 : : * to delete such states.
1876 : : *
1877 : : * If the to state has multiple forward-constraint inarcs, and/or multiple
1878 : : * compatible constraint outarcs, we only need to create one new intermediate
1879 : : * state per combination of predecessor and successor states. *intermediates
1880 : : * points to a list of such intermediate states for this to state (chained
1881 : : * through their tmp fields).
1882 : : */
1883 : : static int
2489 1884 : 33423 : push(struct nfa *nfa,
1885 : : struct arc *con,
1886 : : struct state **intermediates)
1887 : : {
7739 1888 : 33423 : struct state *from = con->from;
1889 : 33423 : struct state *to = con->to;
1890 : : struct arc *a;
1891 : : struct arc *nexta;
1892 : : struct state *s;
1893 : :
3103 1894 [ - + ]: 33423 : assert(to != from); /* should have gotten rid of this earlier */
7559 bruce@momjian.us 1895 [ + + ]: 33423 : if (to->flag) /* can't push forward beyond end */
7739 tgl@sss.pgh.pa.us 1896 : 22876 : return 0;
7559 bruce@momjian.us 1897 [ + + ]: 10547 : if (to->nouts == 0)
1898 : : { /* dead end */
7739 tgl@sss.pgh.pa.us 1899 : 410 : freearc(nfa, con);
1900 : 410 : return 1;
1901 : : }
1902 : :
1903 : : /*
1904 : : * First, clone to state if necessary to avoid other inarcs. This may
1905 : : * seem wasteful, but it simplifies the logic, and we'll get rid of the
1906 : : * clone state again at the bottom.
1907 : : */
7559 bruce@momjian.us 1908 [ + + ]: 10137 : if (to->nins > 1)
1909 : : {
7739 tgl@sss.pgh.pa.us 1910 : 5429 : s = newstate(nfa);
1911 [ - + ]: 5429 : if (NISERR())
7739 tgl@sss.pgh.pa.us 1912 :UBC 0 : return 0;
3103 tgl@sss.pgh.pa.us 1913 :CBC 5429 : copyouts(nfa, to, s); /* duplicate outarcs */
2489 1914 : 5429 : cparc(nfa, con, from, s); /* move constraint arc */
7739 1915 : 5429 : freearc(nfa, con);
3103 1916 [ - + ]: 5429 : if (NISERR())
3103 tgl@sss.pgh.pa.us 1917 :UBC 0 : return 0;
7739 tgl@sss.pgh.pa.us 1918 :CBC 5429 : to = s;
1919 : 5429 : con = to->ins;
1920 : : }
1921 [ - + ]: 10137 : assert(to->nins == 1);
1922 : :
1923 : : /* propagate the constraint into the to state's outarcs */
3103 1924 [ + + + - ]: 62788 : for (a = to->outs; a != NULL && !NISERR(); a = nexta)
1925 : : {
7739 1926 : 52651 : nexta = a->outchain;
1149 1927 [ + + + + : 52651 : switch (combine(nfa, con, a))
- ]
1928 : : {
7559 bruce@momjian.us 1929 : 44604 : case INCOMPATIBLE: /* destroy the arc */
1930 : 44604 : freearc(nfa, a);
1931 : 44604 : break;
1932 : 6856 : case SATISFIED: /* no action needed */
1933 : 6856 : break;
1934 : 8 : case COMPATIBLE: /* swap the two arcs, more or less */
1935 : : /* need an intermediate state, but might have one already */
3103 tgl@sss.pgh.pa.us 1936 [ + + ]: 8 : for (s = *intermediates; s != NULL; s = s->tmp)
1937 : : {
1938 [ + - - + ]: 6 : assert(s->nins > 0 && s->nouts > 0);
1939 [ + - + - ]: 6 : if (s->ins->from == from && s->outs->to == a->to)
1940 : 6 : break;
1941 : : }
1942 [ + + ]: 8 : if (s == NULL)
1943 : : {
1944 : 2 : s = newstate(nfa);
1945 [ - + ]: 2 : if (NISERR())
3103 tgl@sss.pgh.pa.us 1946 :UBC 0 : return 0;
3103 tgl@sss.pgh.pa.us 1947 :CBC 2 : s->tmp = *intermediates;
1948 : 2 : *intermediates = s;
1949 : : }
1950 : 8 : cparc(nfa, con, s, a->to);
7559 bruce@momjian.us 1951 : 8 : cparc(nfa, a, from, s);
1952 : 8 : freearc(nfa, a);
1953 : 8 : break;
1149 tgl@sss.pgh.pa.us 1954 : 1183 : case REPLACEARC: /* replace arc's color */
1955 : 1183 : newarc(nfa, a->type, con->co, from, a->to);
1956 : 1183 : freearc(nfa, a);
1957 : 1183 : break;
7559 bruce@momjian.us 1958 :UBC 0 : default:
1959 : 0 : assert(NOTREACHED);
1960 : : break;
1961 : : }
1962 : : }
1963 : :
1964 : : /* remaining outarcs, if any, incorporate the constraint */
7739 tgl@sss.pgh.pa.us 1965 :CBC 10137 : moveouts(nfa, to, from);
3103 1966 : 10137 : freearc(nfa, con);
1967 : : /* to state is now useless, but we leave it to pushfwd() to clean up */
7739 1968 : 10137 : return 1;
1969 : : }
1970 : :
1971 : : /*
1972 : : * combine - constraint lands on an arc, what happens?
1973 : : *
1974 : : * #def INCOMPATIBLE 1 // destroys arc
1975 : : * #def SATISFIED 2 // constraint satisfied
1976 : : * #def COMPATIBLE 3 // compatible but not satisfied yet
1977 : : * #def REPLACEARC 4 // replace arc's color with constraint color
1978 : : */
1979 : : static int
1149 1980 : 192940 : combine(struct nfa *nfa,
1981 : : struct arc *con,
1982 : : struct arc *a)
1983 : : {
1984 : : #define CA(ct,at) (((ct)<<CHAR_BIT) | (at))
1985 : :
7559 bruce@momjian.us 1986 [ + + + + : 192940 : switch (CA(con->type, a->type))
+ + - ]
1987 : : {
1988 : 43718 : case CA('^', PLAIN): /* newlines are handled separately */
1989 : : case CA('$', PLAIN):
1990 : 43718 : return INCOMPATIBLE;
1991 : : break;
1992 : 17680 : case CA(AHEAD, PLAIN): /* color constraints meet colors */
1993 : : case CA(BEHIND, PLAIN):
1994 [ + + ]: 17680 : if (con->co == a->co)
1995 : 781 : return SATISFIED;
1149 tgl@sss.pgh.pa.us 1996 [ + + ]: 16899 : if (con->co == RAINBOW)
1997 : : {
1998 : : /* con is satisfied unless arc's color is a pseudocolor */
1999 [ + - ]: 2 : if (!(nfa->cm->cd[a->co].flags & PSEUDO))
2000 : 2 : return SATISFIED;
2001 : : }
2002 [ + + ]: 16897 : else if (a->co == RAINBOW)
2003 : : {
2004 : : /* con is incompatible if it's for a pseudocolor */
2005 : : /* (this is hypothetical; we make no such constraints today) */
2006 [ - + ]: 1943 : if (nfa->cm->cd[con->co].flags & PSEUDO)
1149 tgl@sss.pgh.pa.us 2007 :UBC 0 : return INCOMPATIBLE;
2008 : : /* otherwise, constraint constrains arc to be only its color */
1149 tgl@sss.pgh.pa.us 2009 :CBC 1943 : return REPLACEARC;
2010 : : }
7559 bruce@momjian.us 2011 : 14954 : return INCOMPATIBLE;
2012 : : break;
2013 : 23355 : case CA('^', '^'): /* collision, similar constraints */
2014 : : case CA('$', '$'):
1149 tgl@sss.pgh.pa.us 2015 [ + + ]: 23355 : if (con->co == a->co) /* true duplication */
2016 : 13380 : return SATISFIED;
2017 : 9975 : return INCOMPATIBLE;
2018 : : break;
2019 : 12310 : case CA(AHEAD, AHEAD): /* collision, similar constraints */
2020 : : case CA(BEHIND, BEHIND):
2489 2021 [ + + ]: 12310 : if (con->co == a->co) /* true duplication */
7559 bruce@momjian.us 2022 : 459 : return SATISFIED;
1149 tgl@sss.pgh.pa.us 2023 [ + + ]: 11851 : if (con->co == RAINBOW)
2024 : : {
2025 : : /* con is satisfied unless arc's color is a pseudocolor */
2026 [ + - ]: 2 : if (!(nfa->cm->cd[a->co].flags & PSEUDO))
2027 : 2 : return SATISFIED;
2028 : : }
2029 [ + + ]: 11849 : else if (a->co == RAINBOW)
2030 : : {
2031 : : /* con is incompatible if it's for a pseudocolor */
2032 : : /* (this is hypothetical; we make no such constraints today) */
2033 [ - + ]: 4 : if (nfa->cm->cd[con->co].flags & PSEUDO)
1149 tgl@sss.pgh.pa.us 2034 :UBC 0 : return INCOMPATIBLE;
2035 : : /* otherwise, constraint constrains arc to be only its color */
1149 tgl@sss.pgh.pa.us 2036 :CBC 4 : return REPLACEARC;
2037 : : }
7559 bruce@momjian.us 2038 : 11845 : return INCOMPATIBLE;
2039 : : break;
2040 : 6026 : case CA('^', BEHIND): /* collision, dissimilar constraints */
2041 : : case CA(BEHIND, '^'):
2042 : : case CA('$', AHEAD):
2043 : : case CA(AHEAD, '$'):
2044 : 6026 : return INCOMPATIBLE;
2045 : : break;
2046 : 89851 : case CA('^', '$'): /* constraints passing each other */
2047 : : case CA('^', AHEAD):
2048 : : case CA(BEHIND, '$'):
2049 : : case CA(BEHIND, AHEAD):
2050 : : case CA('$', '^'):
2051 : : case CA('$', BEHIND):
2052 : : case CA(AHEAD, '^'):
2053 : : case CA(AHEAD, BEHIND):
2054 : : case CA('^', LACON):
2055 : : case CA(BEHIND, LACON):
2056 : : case CA('$', LACON):
2057 : : case CA(AHEAD, LACON):
2058 : 89851 : return COMPATIBLE;
2059 : : break;
2060 : : }
7739 tgl@sss.pgh.pa.us 2061 :UBC 0 : assert(NOTREACHED);
2062 : : return INCOMPATIBLE; /* for benefit of blind compilers */
2063 : : }
2064 : :
2065 : : /*
2066 : : * fixempties - get rid of EMPTY arcs
2067 : : */
2068 : : static void
2489 tgl@sss.pgh.pa.us 2069 :CBC 8886 : fixempties(struct nfa *nfa,
2070 : : FILE *f) /* for debug output; NULL none */
2071 : : {
2072 : : struct state *s;
2073 : : struct state *s2;
2074 : : struct state *nexts;
2075 : : struct arc *a;
2076 : : struct arc *nexta;
2077 : : int totalinarcs;
2078 : : struct arc **inarcsorig;
2079 : : struct arc **arcarray;
2080 : : int arccount;
2081 : : int prevnins;
2082 : : int nskip;
2083 : :
2084 : : /*
2085 : : * First, get rid of any states whose sole out-arc is an EMPTY, since
2086 : : * they're basically just aliases for their successor. The parsing
2087 : : * algorithm creates enough of these that it's worth special-casing this.
2088 : : */
4056 2089 [ + + + - ]: 211498 : for (s = nfa->states; s != NULL && !NISERR(); s = nexts)
2090 : : {
2091 : 202612 : nexts = s->next;
2092 [ + + + + ]: 202612 : if (s->flag || s->nouts != 1)
2093 : 52573 : continue;
2094 : 150039 : a = s->outs;
2095 [ + - - + ]: 150039 : assert(a != NULL && a->outchain == NULL);
2096 [ + + ]: 150039 : if (a->type != EMPTY)
2097 : 89974 : continue;
2098 [ + - ]: 60065 : if (s != a->to)
2099 : 60065 : moveins(nfa, s, a->to);
2100 : 60065 : dropstate(nfa, s);
2101 : : }
2102 : :
2103 : : /*
2104 : : * Similarly, get rid of any state with a single EMPTY in-arc, by folding
2105 : : * it into its predecessor.
2106 : : */
2107 [ + + + - ]: 151433 : for (s = nfa->states; s != NULL && !NISERR(); s = nexts)
2108 : : {
2109 : 142547 : nexts = s->next;
2110 : : /* while we're at it, ensure tmp fields are clear for next step */
2111 [ - + ]: 142547 : assert(s->tmp == NULL);
2112 [ + + + + ]: 142547 : if (s->flag || s->nins != 1)
2113 : 49765 : continue;
2114 : 92782 : a = s->ins;
2115 [ + - - + ]: 92782 : assert(a != NULL && a->inchain == NULL);
2116 [ + + ]: 92782 : if (a->type != EMPTY)
2117 : 81294 : continue;
2118 [ + - ]: 11488 : if (s != a->from)
2119 : 11488 : moveouts(nfa, s, a->from);
2120 : 11488 : dropstate(nfa, s);
2121 : : }
2122 : :
3103 2123 [ - + ]: 8886 : if (NISERR())
3103 tgl@sss.pgh.pa.us 2124 :UBC 0 : return;
2125 : :
2126 : : /*
2127 : : * For each remaining NFA state, find all other states from which it is
2128 : : * reachable by a chain of one or more EMPTY arcs. Then generate new arcs
2129 : : * that eliminate the need for each such chain.
2130 : : *
2131 : : * We could replace a chain of EMPTY arcs that leads from a "from" state
2132 : : * to a "to" state either by pushing non-EMPTY arcs forward (linking
2133 : : * directly from "from"'s predecessors to "to") or by pulling them back
2134 : : * (linking directly from "from" to "to"'s successors). We choose to
2135 : : * always do the former; this choice is somewhat arbitrary, but the
2136 : : * approach below requires that we uniformly do one or the other.
2137 : : *
2138 : : * Suppose we have a chain of N successive EMPTY arcs (where N can easily
2139 : : * approach the size of the NFA). All of the intermediate states must
2140 : : * have additional inarcs and outarcs, else they'd have been removed by
2141 : : * the steps above. Assuming their inarcs are mostly not empties, we will
2142 : : * add O(N^2) arcs to the NFA, since a non-EMPTY inarc leading to any one
2143 : : * state in the chain must be duplicated to lead to all its successor
2144 : : * states as well. So there is no hope of doing less than O(N^2) work;
2145 : : * however, we should endeavor to keep the big-O cost from being even
2146 : : * worse than that, which it can easily become without care. In
2147 : : * particular, suppose we were to copy all S1's inarcs forward to S2, and
2148 : : * then also to S3, and then later we consider pushing S2's inarcs forward
2149 : : * to S3. If we include the arcs already copied from S1 in that, we'd be
2150 : : * doing O(N^3) work. (The duplicate-arc elimination built into newarc()
2151 : : * and its cohorts would get rid of the extra arcs, but not without cost.)
2152 : : *
2153 : : * We can avoid this cost by treating only arcs that existed at the start
2154 : : * of this phase as candidates to be pushed forward. To identify those,
2155 : : * we remember the first inarc each state had to start with. We rely on
2156 : : * the fact that newarc() and friends put new arcs on the front of their
2157 : : * to-states' inchains, and that this phase never deletes arcs, so that
2158 : : * the original arcs must be the last arcs in their to-states' inchains.
2159 : : *
2160 : : * So the process here is that, for each state in the NFA, we gather up
2161 : : * all non-EMPTY inarcs of states that can reach the target state via
2162 : : * EMPTY arcs. We then sort, de-duplicate, and merge these arcs into the
2163 : : * target state's inchain. (We can safely use sort-merge for this as long
2164 : : * as we update each state's original-arcs pointer after we add arcs to
2165 : : * it; the sort step of mergeins probably changed the order of the old
2166 : : * arcs.)
2167 : : *
2168 : : * Another refinement worth making is that, because we only add non-EMPTY
2169 : : * arcs during this phase, and all added arcs have the same from-state as
2170 : : * the non-EMPTY arc they were cloned from, we know ahead of time that any
2171 : : * states having only EMPTY outarcs will be useless for lack of outarcs
2172 : : * after we drop the EMPTY arcs. (They cannot gain non-EMPTY outarcs if
2173 : : * they had none to start with.) So we need not bother to update the
2174 : : * inchains of such states at all.
2175 : : */
2176 : :
2177 : : /* Remember the states' first original inarcs */
2178 : : /* ... and while at it, count how many old inarcs there are altogether */
3103 tgl@sss.pgh.pa.us 2179 :CBC 8886 : inarcsorig = (struct arc **) MALLOC(nfa->nstates * sizeof(struct arc *));
2180 [ - + ]: 8886 : if (inarcsorig == NULL)
2181 : : {
3103 tgl@sss.pgh.pa.us 2182 [ # # ]:UBC 0 : NERR(REG_ESPACE);
2183 : 0 : return;
2184 : : }
3103 tgl@sss.pgh.pa.us 2185 :CBC 8886 : totalinarcs = 0;
2186 [ + + ]: 139945 : for (s = nfa->states; s != NULL; s = s->next)
2187 : : {
2188 : 131059 : inarcsorig[s->no] = s->ins;
2189 : 131059 : totalinarcs += s->nins;
2190 : : }
2191 : :
2192 : : /*
2193 : : * Create a workspace for accumulating the inarcs to be added to the
2194 : : * current target state. totalinarcs is probably a considerable
2195 : : * overestimate of the space needed, but the NFA is unlikely to be large
2196 : : * enough at this point to make it worth being smarter.
2197 : : */
2198 : 8886 : arcarray = (struct arc **) MALLOC(totalinarcs * sizeof(struct arc *));
2199 [ - + ]: 8886 : if (arcarray == NULL)
2200 : : {
3103 tgl@sss.pgh.pa.us 2201 [ # # ]:UBC 0 : NERR(REG_ESPACE);
2202 : 0 : FREE(inarcsorig);
2203 : 0 : return;
2204 : : }
2205 : :
2206 : : /* And iterate over the target states */
4056 tgl@sss.pgh.pa.us 2207 [ + + + + ]:CBC 137464 : for (s = nfa->states; s != NULL && !NISERR(); s = s->next)
2208 : : {
2209 : : /* Ignore target states without non-EMPTY outarcs, per note above */
3103 2210 [ + + + + ]: 128578 : if (!s->flag && !hasnonemptyout(s))
2211 : 1974 : continue;
2212 : :
2213 : : /* Find predecessor states and accumulate their original inarcs */
2214 : 126604 : arccount = 0;
2215 [ + + ]: 7620059 : for (s2 = emptyreachable(nfa, s, s, inarcsorig); s2 != s; s2 = nexts)
2216 : : {
2217 : : /* Add s2's original inarcs to arcarray[], but ignore empties */
2218 [ + + ]: 22501255 : for (a = inarcsorig[s2->no]; a != NULL; a = a->inchain)
2219 : : {
2220 [ + + ]: 15007800 : if (a->type != EMPTY)
2221 : 7515293 : arcarray[arccount++] = a;
2222 : : }
2223 : :
2224 : : /* Reset the tmp fields as we walk back */
4056 2225 : 7493455 : nexts = s2->tmp;
2226 : 7493455 : s2->tmp = NULL;
2227 : : }
2228 : 126604 : s->tmp = NULL;
3103 2229 [ - + ]: 126604 : assert(arccount <= totalinarcs);
2230 : :
2231 : : /* Remember how many original inarcs this state has */
2232 : 126604 : prevnins = s->nins;
2233 : :
2234 : : /* Add non-duplicate inarcs to target state */
2235 : 126604 : mergeins(nfa, s, arcarray, arccount);
2236 : :
2237 : : /* Now we must update the state's inarcsorig pointer */
2238 : 126604 : nskip = s->nins - prevnins;
2239 : 126604 : a = s->ins;
2240 [ + + ]: 7635572 : while (nskip-- > 0)
2241 : 7508968 : a = a->inchain;
2242 : 126604 : inarcsorig[s->no] = a;
2243 : : }
2244 : :
2245 : 8886 : FREE(arcarray);
2246 : 8886 : FREE(inarcsorig);
2247 : :
4056 2248 [ + + ]: 8886 : if (NISERR())
2249 : 3 : return;
2250 : :
2251 : : /*
2252 : : * Now remove all the EMPTY arcs, since we don't need them anymore.
2253 : : */
2254 [ + + ]: 130936 : for (s = nfa->states; s != NULL; s = s->next)
2255 : : {
2256 [ + + ]: 734854 : for (a = s->outs; a != NULL; a = nexta)
2257 : : {
2258 : 612801 : nexta = a->outchain;
2259 [ + + ]: 612801 : if (a->type == EMPTY)
2260 : 12639 : freearc(nfa, a);
2261 : : }
2262 : : }
2263 : :
2264 : : /*
2265 : : * And remove any states that have become useless. (This cleanup is not
2266 : : * very thorough, and would be even less so if we tried to combine it with
2267 : : * the previous step; but cleanup() will take care of anything we miss.)
2268 : : */
2269 [ + + ]: 130936 : for (s = nfa->states; s != NULL; s = nexts)
2270 : : {
2271 : 122053 : nexts = s->next;
2272 [ + + + + : 122053 : if ((s->nins == 0 || s->nouts == 0) && !s->flag)
+ + ]
2273 : 1974 : dropstate(nfa, s);
2274 : : }
2275 : :
2276 [ - + ]: 8883 : if (f != NULL)
4056 tgl@sss.pgh.pa.us 2277 :UBC 0 : dumpnfa(nfa, f);
2278 : : }
2279 : :
2280 : : /*
2281 : : * emptyreachable - recursively find all states that can reach s by EMPTY arcs
2282 : : *
2283 : : * The return value is the last such state found. Its tmp field links back
2284 : : * to the next-to-last such state, and so on back to s, so that all these
2285 : : * states can be located without searching the whole NFA.
2286 : : *
2287 : : * Since this is only used in fixempties(), we pass in the inarcsorig[] array
2288 : : * maintained by that function. This lets us skip over all new inarcs, which
2289 : : * are certainly not EMPTY arcs.
2290 : : *
2291 : : * The maximum recursion depth here is equal to the length of the longest
2292 : : * loop-free chain of EMPTY arcs, which is surely no more than the size of
2293 : : * the NFA ... but that could still be enough to cause trouble.
2294 : : */
2295 : : static struct state *
2489 tgl@sss.pgh.pa.us 2296 :CBC 7620059 : emptyreachable(struct nfa *nfa,
2297 : : struct state *s,
2298 : : struct state *lastfound,
2299 : : struct arc **inarcsorig)
2300 : : {
2301 : : struct arc *a;
2302 : :
2303 : : /* Since this is recursive, it could be driven to stack overflow */
3117 2304 [ - + ]: 7620059 : if (STACK_TOO_DEEP(nfa->v->re))
2305 : : {
3117 tgl@sss.pgh.pa.us 2306 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
2307 : 0 : return lastfound;
2308 : : }
2309 : :
4056 tgl@sss.pgh.pa.us 2310 :CBC 7620059 : s->tmp = lastfound;
2311 : 7620059 : lastfound = s;
3103 2312 [ + + ]: 22834192 : for (a = inarcsorig[s->no]; a != NULL; a = a->inchain)
2313 : : {
2314 [ + + + + ]: 15214133 : if (a->type == EMPTY && a->from->tmp == NULL)
2315 : 7493455 : lastfound = emptyreachable(nfa, a->from, lastfound, inarcsorig);
2316 : : }
4056 2317 : 7620059 : return lastfound;
2318 : : }
2319 : :
2320 : : /*
2321 : : * isconstraintarc - detect whether an arc is of a constraint type
2322 : : */
2323 : : static inline int
2489 2324 : 1266541 : isconstraintarc(struct arc *a)
2325 : : {
3103 2326 [ + + ]: 1266541 : switch (a->type)
2327 : : {
2328 : 154719 : case '^':
2329 : : case '$':
2330 : : case BEHIND:
2331 : : case AHEAD:
2332 : : case LACON:
2333 : 154719 : return 1;
2334 : : }
2335 : 1111822 : return 0;
2336 : : }
2337 : :
2338 : : /*
2339 : : * hasconstraintout - does state have a constraint out arc?
2340 : : */
2341 : : static int
2489 2342 : 12631 : hasconstraintout(struct state *s)
2343 : : {
2344 : : struct arc *a;
2345 : :
3103 2346 [ + + ]: 23960 : for (a = s->outs; a != NULL; a = a->outchain)
2347 : : {
2348 [ + + ]: 19222 : if (isconstraintarc(a))
2349 : 7893 : return 1;
2350 : : }
2351 : 4738 : return 0;
2352 : : }
2353 : :
2354 : : /*
2355 : : * fixconstraintloops - get rid of loops containing only constraint arcs
2356 : : *
2357 : : * A loop of states that contains only constraint arcs is useless, since
2358 : : * passing around the loop represents no forward progress. Moreover, it
2359 : : * would cause infinite looping in pullback/pushfwd, so we need to get rid
2360 : : * of such loops before doing that.
2361 : : */
2362 : : static void
2489 2363 : 8886 : fixconstraintloops(struct nfa *nfa,
2364 : : FILE *f) /* for debug output; NULL none */
2365 : : {
2366 : : struct state *s;
2367 : : struct state *nexts;
2368 : : struct arc *a;
2369 : : struct arc *nexta;
2370 : : int hasconstraints;
2371 : :
2372 : : /*
2373 : : * In the trivial case of a state that loops to itself, we can just drop
2374 : : * the constraint arc altogether. This is worth special-casing because
2375 : : * such loops are far more common than loops containing multiple states.
2376 : : * While we're at it, note whether any constraint arcs survive.
2377 : : */
3103 2378 : 8886 : hasconstraints = 0;
2379 [ + + + + ]: 128965 : for (s = nfa->states; s != NULL && !NISERR(); s = nexts)
2380 : : {
2381 : 120079 : nexts = s->next;
2382 : : /* while we're at it, ensure tmp fields are clear for next step */
2383 [ - + ]: 120079 : assert(s->tmp == NULL);
2384 [ + + + - ]: 718268 : for (a = s->outs; a != NULL && !NISERR(); a = nexta)
2385 : : {
2386 : 598189 : nexta = a->outchain;
2387 [ + + ]: 598189 : if (isconstraintarc(a))
2388 : : {
2389 [ + + ]: 56261 : if (a->to == s)
2390 : 176 : freearc(nfa, a);
2391 : : else
2392 : 56085 : hasconstraints = 1;
2393 : : }
2394 : : }
2395 : : /* If we removed all the outarcs, the state is useless. */
2396 [ + + - + ]: 120079 : if (s->nouts == 0 && !s->flag)
3103 tgl@sss.pgh.pa.us 2397 :UBC 0 : dropstate(nfa, s);
2398 : : }
2399 : :
2400 : : /* Nothing to do if no remaining constraint arcs */
3103 tgl@sss.pgh.pa.us 2401 [ + + + - ]:CBC 8886 : if (NISERR() || !hasconstraints)
2402 : 3 : return;
2403 : :
2404 : : /*
2405 : : * Starting from each remaining NFA state, search outwards for a
2406 : : * constraint loop. If we find a loop, break the loop, then start the
2407 : : * search over. (We could possibly retain some state from the first scan,
2408 : : * but it would complicate things greatly, and multi-state constraint
2409 : : * loops are rare enough that it's not worth optimizing the case.)
2410 : : */
2411 : 8883 : restart:
2412 [ + + + - ]: 136429 : for (s = nfa->states; s != NULL && !NISERR(); s = s->next)
2413 : : {
2414 [ + + ]: 127546 : if (findconstraintloop(nfa, s))
2415 : 206 : goto restart;
2416 : : }
2417 : :
2418 [ - + ]: 8883 : if (NISERR())
3103 tgl@sss.pgh.pa.us 2419 :UBC 0 : return;
2420 : :
2421 : : /*
2422 : : * Now remove any states that have become useless. (This cleanup is not
2423 : : * very thorough, and would be even less so if we tried to combine it with
2424 : : * the previous step; but cleanup() will take care of anything we miss.)
2425 : : *
2426 : : * Because findconstraintloop intentionally doesn't reset all tmp fields,
2427 : : * we have to clear them after it's done. This is a convenient place to
2428 : : * do that, too.
2429 : : */
3103 tgl@sss.pgh.pa.us 2430 [ + + ]:CBC 129823 : for (s = nfa->states; s != NULL; s = nexts)
2431 : : {
2432 : 120940 : nexts = s->next;
2433 : 120940 : s->tmp = NULL;
2434 [ + + + + : 120940 : if ((s->nins == 0 || s->nouts == 0) && !s->flag)
+ + ]
2435 : 213 : dropstate(nfa, s);
2436 : : }
2437 : :
2438 [ - + ]: 8883 : if (f != NULL)
3103 tgl@sss.pgh.pa.us 2439 :UBC 0 : dumpnfa(nfa, f);
2440 : : }
2441 : :
2442 : : /*
2443 : : * findconstraintloop - recursively find a loop of constraint arcs
2444 : : *
2445 : : * If we find a loop, break it by calling breakconstraintloop(), then
2446 : : * return 1; otherwise return 0.
2447 : : *
2448 : : * State tmp fields are guaranteed all NULL on a success return, because
2449 : : * breakconstraintloop does that. After a failure return, any state that
2450 : : * is known not to be part of a loop is marked with s->tmp == s; this allows
2451 : : * us not to have to re-prove that fact on later calls. (This convention is
2452 : : * workable because we already eliminated single-state loops.)
2453 : : *
2454 : : * Note that the found loop doesn't necessarily include the first state we
2455 : : * are called on. Any loop reachable from that state will do.
2456 : : *
2457 : : * The maximum recursion depth here is one more than the length of the longest
2458 : : * loop-free chain of constraint arcs, which is surely no more than the size
2459 : : * of the NFA ... but that could still be enough to cause trouble.
2460 : : */
2461 : : static int
2489 tgl@sss.pgh.pa.us 2462 :CBC 203695 : findconstraintloop(struct nfa *nfa, struct state *s)
2463 : : {
2464 : : struct arc *a;
2465 : :
2466 : : /* Since this is recursive, it could be driven to stack overflow */
3103 2467 [ - + ]: 203695 : if (STACK_TOO_DEEP(nfa->v->re))
2468 : : {
3103 tgl@sss.pgh.pa.us 2469 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
2470 : 0 : return 1; /* to exit as quickly as possible */
2471 : : }
2472 : :
3103 tgl@sss.pgh.pa.us 2473 [ + + ]:CBC 203695 : if (s->tmp != NULL)
2474 : : {
2475 : : /* Already proven uninteresting? */
2476 [ + + ]: 73779 : if (s->tmp == s)
2477 : 73573 : return 0;
2478 : : /* Found a loop involving s */
2479 : 206 : breakconstraintloop(nfa, s);
2480 : : /* The tmp fields have been cleaned up by breakconstraintloop */
2481 : 206 : return 1;
2482 : : }
2483 [ + + ]: 763450 : for (a = s->outs; a != NULL; a = a->outchain)
2484 : : {
2485 [ + + ]: 634193 : if (isconstraintarc(a))
2486 : : {
2487 : 76149 : struct state *sto = a->to;
2488 : :
2489 [ - + ]: 76149 : assert(sto != s);
2490 : 76149 : s->tmp = sto;
2491 [ + + ]: 76149 : if (findconstraintloop(nfa, sto))
2492 : 659 : return 1;
2493 : : }
2494 : : }
2495 : :
2496 : : /*
2497 : : * If we get here, no constraint loop exists leading out from s. Mark it
2498 : : * with s->tmp == s so we need not rediscover that fact again later.
2499 : : */
2500 : 129257 : s->tmp = s;
2501 : 129257 : return 0;
2502 : : }
2503 : :
2504 : : /*
2505 : : * breakconstraintloop - break a loop of constraint arcs
2506 : : *
2507 : : * sinitial is any one member state of the loop. Each loop member's tmp
2508 : : * field links to its successor within the loop. (Note that this function
2509 : : * will reset all the tmp fields to NULL.)
2510 : : *
2511 : : * We can break the loop by, for any one state S1 in the loop, cloning its
2512 : : * loop successor state S2 (and possibly following states), and then moving
2513 : : * all S1->S2 constraint arcs to point to the cloned S2. The cloned S2 should
2514 : : * copy any non-constraint outarcs of S2. Constraint outarcs should be
2515 : : * dropped if they point back to S1, else they need to be copied as arcs to
2516 : : * similarly cloned states S3, S4, etc. In general, each cloned state copies
2517 : : * non-constraint outarcs, drops constraint outarcs that would lead to itself
2518 : : * or any earlier cloned state, and sends other constraint outarcs to newly
2519 : : * cloned states. No cloned state will have any inarcs that aren't constraint
2520 : : * arcs or do not lead from S1 or earlier-cloned states. It's okay to drop
2521 : : * constraint back-arcs since they would not take us to any state we've not
2522 : : * already been in; therefore, no new constraint loop is created. In this way
2523 : : * we generate a modified NFA that can still represent every useful state
2524 : : * sequence, but not sequences that represent state loops with no consumption
2525 : : * of input data. Note that the set of cloned states will certainly include
2526 : : * all of the loop member states other than S1, and it may also include
2527 : : * non-loop states that are reachable from S2 via constraint arcs. This is
2528 : : * important because there is no guarantee that findconstraintloop found a
2529 : : * maximal loop (and searching for one would be NP-hard, so don't try).
2530 : : * Frequently the "non-loop states" are actually part of a larger loop that
2531 : : * we didn't notice, and indeed there may be several overlapping loops.
2532 : : * This technique ensures convergence in such cases, while considering only
2533 : : * the originally-found loop does not.
2534 : : *
2535 : : * If there is only one S1->S2 constraint arc, then that constraint is
2536 : : * certainly satisfied when we enter any of the clone states. This means that
2537 : : * in the common case where many of the constraint arcs are identically
2538 : : * labeled, we can merge together clone states linked by a similarly-labeled
2539 : : * constraint: if we can get to the first one we can certainly get to the
2540 : : * second, so there's no need to distinguish. This greatly reduces the number
2541 : : * of new states needed, so we preferentially break the given loop at a state
2542 : : * pair where this is true.
2543 : : *
2544 : : * Furthermore, it's fairly common to find that a cloned successor state has
2545 : : * no outarcs, especially if we're a bit aggressive about removing unnecessary
2546 : : * outarcs. If that happens, then there is simply not any interesting state
2547 : : * that can be reached through the predecessor's loop arcs, which means we can
2548 : : * break the loop just by removing those loop arcs, with no new states added.
2549 : : */
2550 : : static void
2489 2551 : 206 : breakconstraintloop(struct nfa *nfa, struct state *sinitial)
2552 : : {
2553 : : struct state *s;
2554 : : struct state *shead;
2555 : : struct state *stail;
2556 : : struct state *sclone;
2557 : : struct state *nexts;
2558 : : struct arc *refarc;
2559 : : struct arc *a;
2560 : : struct arc *nexta;
2561 : :
2562 : : /*
2563 : : * Start by identifying which loop step we want to break at.
2564 : : * Preferentially this is one with only one constraint arc. (XXX are
2565 : : * there any other secondary heuristics we want to use here?) Set refarc
2566 : : * to point to the selected lone constraint arc, if there is one.
2567 : : */
3103 2568 : 206 : refarc = NULL;
2569 : 206 : s = sinitial;
2570 : : do
2571 : : {
2572 : 530 : nexts = s->tmp;
2573 [ - + ]: 530 : assert(nexts != s); /* should not see any one-element loops */
2574 [ + + ]: 530 : if (refarc == NULL)
2575 : : {
2576 : 332 : int narcs = 0;
2577 : :
2578 [ + + ]: 3800 : for (a = s->outs; a != NULL; a = a->outchain)
2579 : : {
2580 [ + + + - ]: 3468 : if (a->to == nexts && isconstraintarc(a))
2581 : : {
2582 : 1296 : refarc = a;
2583 : 1296 : narcs++;
2584 : : }
2585 : : }
2586 [ - + ]: 332 : assert(narcs > 0);
2587 [ + + ]: 332 : if (narcs > 1)
2588 : 186 : refarc = NULL; /* multiple constraint arcs here, no good */
2589 : : }
2590 : 530 : s = nexts;
2591 [ + + ]: 530 : } while (s != sinitial);
2592 : :
2593 [ + + ]: 206 : if (refarc)
2594 : : {
2595 : : /* break at the refarc */
2596 : 146 : shead = refarc->from;
2597 : 146 : stail = refarc->to;
2598 [ - + ]: 146 : assert(stail == shead->tmp);
2599 : : }
2600 : : else
2601 : : {
2602 : : /* for lack of a better idea, break after sinitial */
2603 : 60 : shead = sinitial;
2604 : 60 : stail = sinitial->tmp;
2605 : : }
2606 : :
2607 : : /*
2608 : : * Reset the tmp fields so that we can use them for local storage in
2609 : : * clonesuccessorstates. (findconstraintloop won't mind, since it's just
2610 : : * going to abandon its search anyway.)
2611 : : */
2612 [ + + ]: 17361 : for (s = nfa->states; s != NULL; s = s->next)
2613 : 17155 : s->tmp = NULL;
2614 : :
2615 : : /*
2616 : : * Recursively build clone state(s) as needed.
2617 : : */
2618 : 206 : sclone = newstate(nfa);
2619 [ - + ]: 206 : if (sclone == NULL)
2620 : : {
3103 tgl@sss.pgh.pa.us 2621 [ # # ]:UBC 0 : assert(NISERR());
2622 : 0 : return;
2623 : : }
2624 : :
3103 tgl@sss.pgh.pa.us 2625 :CBC 206 : clonesuccessorstates(nfa, stail, sclone, shead, refarc,
2626 : : NULL, NULL, nfa->nstates);
2627 : :
2628 [ - + ]: 206 : if (NISERR())
3103 tgl@sss.pgh.pa.us 2629 :UBC 0 : return;
2630 : :
2631 : : /*
2632 : : * It's possible that sclone has no outarcs at all, in which case it's
2633 : : * useless. (We don't try extremely hard to get rid of useless states
2634 : : * here, but this is an easy and fairly common case.)
2635 : : */
3103 tgl@sss.pgh.pa.us 2636 [ + + ]:CBC 206 : if (sclone->nouts == 0)
2637 : : {
2638 : 49 : freestate(nfa, sclone);
2639 : 49 : sclone = NULL;
2640 : : }
2641 : :
2642 : : /*
2643 : : * Move shead's constraint-loop arcs to point to sclone, or just drop them
2644 : : * if we discovered we don't need sclone.
2645 : : */
2646 [ + + ]: 2256 : for (a = shead->outs; a != NULL; a = nexta)
2647 : : {
2648 : 2050 : nexta = a->outchain;
2649 [ + + + - ]: 2050 : if (a->to == stail && isconstraintarc(a))
2650 : : {
2651 [ + + ]: 489 : if (sclone)
2652 : 412 : cparc(nfa, a, shead, sclone);
2653 : 489 : freearc(nfa, a);
2654 [ - + ]: 489 : if (NISERR())
3103 tgl@sss.pgh.pa.us 2655 :UBC 0 : break;
2656 : : }
2657 : : }
2658 : : }
2659 : :
2660 : : /*
2661 : : * clonesuccessorstates - create a tree of constraint-arc successor states
2662 : : *
2663 : : * ssource is the state to be cloned, and sclone is the state to copy its
2664 : : * outarcs into. sclone's inarcs, if any, should already be set up.
2665 : : *
2666 : : * spredecessor is the original predecessor state that we are trying to build
2667 : : * successors for (it may not be the immediate predecessor of ssource).
2668 : : * refarc, if not NULL, is the original constraint arc that is known to have
2669 : : * been traversed out of spredecessor to reach the successor(s).
2670 : : *
2671 : : * For each cloned successor state, we transiently create a "donemap" that is
2672 : : * a boolean array showing which source states we've already visited for this
2673 : : * clone state. This prevents infinite recursion as well as useless repeat
2674 : : * visits to the same state subtree (which can add up fast, since typical NFAs
2675 : : * have multiple redundant arc pathways). Each donemap is a char array
2676 : : * indexed by state number. The donemaps are all of the same size "nstates",
2677 : : * which is nfa->nstates as of the start of the recursion. This is enough to
2678 : : * have entries for all pre-existing states, but *not* entries for clone
2679 : : * states created during the recursion. That's okay since we have no need to
2680 : : * mark those.
2681 : : *
2682 : : * curdonemap is NULL when recursing to a new sclone state, or sclone's
2683 : : * donemap when we are recursing without having created a new state (which we
2684 : : * do when we decide we can merge a successor state into the current clone
2685 : : * state). outerdonemap is NULL at the top level and otherwise the parent
2686 : : * clone state's donemap.
2687 : : *
2688 : : * The successor states we create and fill here form a strict tree structure,
2689 : : * with each state having exactly one predecessor, except that the toplevel
2690 : : * state has no inarcs as yet (breakconstraintloop will add its inarcs from
2691 : : * spredecessor after we're done). Thus, we can examine sclone's inarcs back
2692 : : * to the root, plus refarc if any, to identify the set of constraints already
2693 : : * known valid at the current point. This allows us to avoid generating extra
2694 : : * successor states.
2695 : : */
2696 : : static void
2489 tgl@sss.pgh.pa.us 2697 :CBC 1811 : clonesuccessorstates(struct nfa *nfa,
2698 : : struct state *ssource,
2699 : : struct state *sclone,
2700 : : struct state *spredecessor,
2701 : : struct arc *refarc,
2702 : : char *curdonemap,
2703 : : char *outerdonemap,
2704 : : int nstates)
2705 : : {
2706 : : char *donemap;
2707 : : struct arc *a;
2708 : :
2709 : : /* Since this is recursive, it could be driven to stack overflow */
3103 2710 [ - + ]: 1811 : if (STACK_TOO_DEEP(nfa->v->re))
2711 : : {
3103 tgl@sss.pgh.pa.us 2712 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
2713 : 0 : return;
2714 : : }
2715 : :
2716 : : /* If this state hasn't already got a donemap, create one */
3103 tgl@sss.pgh.pa.us 2717 :CBC 1811 : donemap = curdonemap;
2718 [ + + ]: 1811 : if (donemap == NULL)
2719 : : {
2720 : 910 : donemap = (char *) MALLOC(nstates * sizeof(char));
2721 [ - + ]: 910 : if (donemap == NULL)
2722 : : {
3103 tgl@sss.pgh.pa.us 2723 [ # # ]:UBC 0 : NERR(REG_ESPACE);
2724 : 0 : return;
2725 : : }
2726 : :
3103 tgl@sss.pgh.pa.us 2727 [ + + ]:CBC 910 : if (outerdonemap != NULL)
2728 : : {
2729 : : /*
2730 : : * Not at outermost recursion level, so copy the outer level's
2731 : : * donemap; this ensures that we see states in process of being
2732 : : * visited at outer levels, or already merged into predecessor
2733 : : * states, as ones we shouldn't traverse back to.
2734 : : */
2735 : 704 : memcpy(donemap, outerdonemap, nstates * sizeof(char));
2736 : : }
2737 : : else
2738 : : {
2739 : : /* At outermost level, only spredecessor is off-limits */
2740 : 206 : memset(donemap, 0, nstates * sizeof(char));
2741 [ - + ]: 206 : assert(spredecessor->no < nstates);
2742 : 206 : donemap[spredecessor->no] = 1;
2743 : : }
2744 : : }
2745 : :
2746 : : /* Mark ssource as visited in the donemap */
2747 [ - + ]: 1811 : assert(ssource->no < nstates);
2748 [ - + ]: 1811 : assert(donemap[ssource->no] == 0);
2749 : 1811 : donemap[ssource->no] = 1;
2750 : :
2751 : : /*
2752 : : * We proceed by first cloning all of ssource's outarcs, creating new
2753 : : * clone states as needed but not doing more with them than that. Then in
2754 : : * a second pass, recurse to process the child clone states. This allows
2755 : : * us to have only one child clone state per reachable source state, even
2756 : : * when there are multiple outarcs leading to the same state. Also, when
2757 : : * we do visit a child state, its set of inarcs is known exactly, which
2758 : : * makes it safe to apply the constraint-is-already-checked optimization.
2759 : : * Also, this ensures that we've merged all the states we can into the
2760 : : * current clone before we recurse to any children, thus possibly saving
2761 : : * them from making extra images of those states.
2762 : : *
2763 : : * While this function runs, child clone states of the current state are
2764 : : * marked by setting their tmp fields to point to the original state they
2765 : : * were cloned from. This makes it possible to detect multiple outarcs
2766 : : * leading to the same state, and also makes it easy to distinguish clone
2767 : : * states from original states (which will have tmp == NULL).
2768 : : */
2769 [ + + + - ]: 14963 : for (a = ssource->outs; a != NULL && !NISERR(); a = a->outchain)
2770 : : {
2771 : 13152 : struct state *sto = a->to;
2772 : :
2773 : : /*
2774 : : * We do not consider cloning successor states that have no constraint
2775 : : * outarcs; just link to them as-is. They cannot be part of a
2776 : : * constraint loop so there is no need to make copies. In particular,
2777 : : * this rule keeps us from trying to clone the post state, which would
2778 : : * be a bad idea.
2779 : : */
2780 [ + + + + ]: 13152 : if (isconstraintarc(a) && hasconstraintout(sto))
2781 : 5485 : {
2782 : : struct state *prevclone;
2783 : : int canmerge;
2784 : : struct arc *a2;
2785 : :
2786 : : /*
2787 : : * Back-link constraint arcs must not be followed. Nor is there a
2788 : : * need to revisit states previously merged into this clone.
2789 : : */
2790 [ - + ]: 7893 : assert(sto->no < nstates);
2791 [ + + ]: 7893 : if (donemap[sto->no] != 0)
2792 : 2408 : continue;
2793 : :
2794 : : /*
2795 : : * Check whether we already have a child clone state for this
2796 : : * source state.
2797 : : */
2798 : 5485 : prevclone = NULL;
2799 [ + + ]: 18762 : for (a2 = sclone->outs; a2 != NULL; a2 = a2->outchain)
2800 : : {
2801 [ + + ]: 17157 : if (a2->to->tmp == sto)
2802 : : {
2803 : 3880 : prevclone = a2->to;
2804 : 3880 : break;
2805 : : }
2806 : : }
2807 : :
2808 : : /*
2809 : : * If this arc is labeled the same as refarc, or the same as any
2810 : : * arc we must have traversed to get to sclone, then no additional
2811 : : * constraints need to be met to get to sto, so we should just
2812 : : * merge its outarcs into sclone.
2813 : : */
2814 [ + + + + : 5485 : if (refarc && a->type == refarc->type && a->co == refarc->co)
+ - ]
2815 : 901 : canmerge = 1;
2816 : : else
2817 : : {
2818 : : struct state *s;
2819 : :
2820 : 4584 : canmerge = 0;
2821 [ + + ]: 22946 : for (s = sclone; s->ins; s = s->ins->from)
2822 : : {
2823 [ + + ]: 18362 : if (s->nins == 1 &&
2824 [ + - - + ]: 18 : a->type == s->ins->type && a->co == s->ins->co)
2825 : : {
3103 tgl@sss.pgh.pa.us 2826 :UBC 0 : canmerge = 1;
2827 : 0 : break;
2828 : : }
2829 : : }
2830 : : }
2831 : :
3103 tgl@sss.pgh.pa.us 2832 [ + + ]:CBC 5485 : if (canmerge)
2833 : : {
2834 : : /*
2835 : : * We can merge into sclone. If we previously made a child
2836 : : * clone state, drop it; there's no need to visit it. (This
2837 : : * can happen if ssource has multiple pathways to sto, and we
2838 : : * only just now found one that is provably a no-op.)
2839 : : */
2840 [ - + ]: 901 : if (prevclone)
3103 tgl@sss.pgh.pa.us 2841 :UBC 0 : dropstate(nfa, prevclone); /* kills our outarc, too */
2842 : :
2843 : : /* Recurse to merge sto's outarcs into sclone */
3103 tgl@sss.pgh.pa.us 2844 :CBC 901 : clonesuccessorstates(nfa,
2845 : : sto,
2846 : : sclone,
2847 : : spredecessor,
2848 : : refarc,
2849 : : donemap,
2850 : : outerdonemap,
2851 : : nstates);
2852 : : /* sto should now be marked as previously visited */
2853 [ + - - + ]: 901 : assert(NISERR() || donemap[sto->no] == 1);
2854 : : }
2855 [ + + ]: 4584 : else if (prevclone)
2856 : : {
2857 : : /*
2858 : : * We already have a clone state for this successor, so just
2859 : : * make another arc to it.
2860 : : */
2861 : 3880 : cparc(nfa, a, sclone, prevclone);
2862 : : }
2863 : : else
2864 : : {
2865 : : /*
2866 : : * We need to create a new successor clone state.
2867 : : */
2868 : : struct state *stoclone;
2869 : :
2870 : 704 : stoclone = newstate(nfa);
2871 [ - + ]: 704 : if (stoclone == NULL)
2872 : : {
3103 tgl@sss.pgh.pa.us 2873 [ # # ]:UBC 0 : assert(NISERR());
2874 : 0 : break;
2875 : : }
2876 : : /* Mark it as to what it's a clone of */
3103 tgl@sss.pgh.pa.us 2877 :CBC 704 : stoclone->tmp = sto;
2878 : : /* ... and add the outarc leading to it */
2879 : 704 : cparc(nfa, a, sclone, stoclone);
2880 : : }
2881 : : }
2882 : : else
2883 : : {
2884 : : /*
2885 : : * Non-constraint outarcs just get copied to sclone, as do outarcs
2886 : : * leading to states with no constraint outarc.
2887 : : */
2888 : 5259 : cparc(nfa, a, sclone, sto);
2889 : : }
2890 : : }
2891 : :
2892 : : /*
2893 : : * If we are at outer level for this clone state, recurse to all its child
2894 : : * clone states, clearing their tmp fields as we go. (If we're not
2895 : : * outermost for sclone, leave this to be done by the outer call level.)
2896 : : * Note that if we have multiple outarcs leading to the same clone state,
2897 : : * it will only be recursed-to once.
2898 : : */
2899 [ + + ]: 1811 : if (curdonemap == NULL)
2900 : : {
2901 [ + + + - ]: 8083 : for (a = sclone->outs; a != NULL && !NISERR(); a = a->outchain)
2902 : : {
2903 : 7173 : struct state *stoclone = a->to;
2904 : 7173 : struct state *sto = stoclone->tmp;
2905 : :
2906 [ + + ]: 7173 : if (sto != NULL)
2907 : : {
2908 : 704 : stoclone->tmp = NULL;
2909 : 704 : clonesuccessorstates(nfa,
2910 : : sto,
2911 : : stoclone,
2912 : : spredecessor,
2913 : : refarc,
2914 : : NULL,
2915 : : donemap,
2916 : : nstates);
2917 : : }
2918 : : }
2919 : :
2920 : : /* Don't forget to free sclone's donemap when done with it */
2921 : 910 : FREE(donemap);
2922 : : }
2923 : : }
2924 : :
2925 : : /*
2926 : : * cleanup - clean up NFA after optimizations
2927 : : */
2928 : : static void
2489 2929 : 17772 : cleanup(struct nfa *nfa)
2930 : : {
2931 : : struct state *s;
2932 : : struct state *nexts;
2933 : : int n;
2934 : :
3117 2935 [ + + ]: 17772 : if (NISERR())
2936 : 3 : return;
2937 : :
2938 : : /* clear out unreachable or dead-end states */
2939 : : /* use pre to mark reachable, then post to mark can-reach-post */
7559 bruce@momjian.us 2940 : 17769 : markreachable(nfa, nfa->pre, (struct state *) NULL, nfa->pre);
7739 tgl@sss.pgh.pa.us 2941 : 17769 : markcanreach(nfa, nfa->post, nfa->pre, nfa->post);
3117 2942 [ + + + - ]: 331518 : for (s = nfa->states; s != NULL && !NISERR(); s = nexts)
2943 : : {
7739 2944 : 313749 : nexts = s->next;
2945 [ + + + + ]: 313749 : if (s->tmp != nfa->post && !s->flag)
2946 : 3120 : dropstate(nfa, s);
2947 : : }
3117 2948 [ + - + + : 17769 : assert(NISERR() || nfa->post->nins == 0 || nfa->post->tmp == nfa->post);
- + ]
7739 2949 : 17769 : cleartraverse(nfa, nfa->pre);
3117 2950 [ + - + + : 17769 : assert(NISERR() || nfa->post->nins == 0 || nfa->post->tmp == NULL);
- + ]
2951 : : /* the nins==0 (final unreachable) case will be caught later */
2952 : :
2953 : : /* renumber surviving states */
7739 2954 : 17769 : n = 0;
2955 [ + + ]: 328398 : for (s = nfa->states; s != NULL; s = s->next)
2956 : 310629 : s->no = n++;
2957 : 17769 : nfa->nstates = n;
2958 : : }
2959 : :
2960 : : /*
2961 : : * markreachable - recursive marking of reachable states
2962 : : */
2963 : : static void
2489 2964 : 863517 : markreachable(struct nfa *nfa,
2965 : : struct state *s,
2966 : : struct state *okay, /* consider only states with this mark */
2967 : : struct state *mark) /* the value to mark with */
2968 : : {
2969 : : struct arc *a;
2970 : :
2971 : : /* Since this is recursive, it could be driven to stack overflow */
3117 2972 [ - + ]: 863517 : if (STACK_TOO_DEEP(nfa->v->re))
2973 : : {
3117 tgl@sss.pgh.pa.us 2974 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
2975 : 0 : return;
2976 : : }
2977 : :
7739 tgl@sss.pgh.pa.us 2978 [ + + ]:CBC 863517 : if (s->tmp != okay)
2979 : 552892 : return;
2980 : 310625 : s->tmp = mark;
2981 : :
2982 [ + + ]: 1156373 : for (a = s->outs; a != NULL; a = a->outchain)
2983 : 845748 : markreachable(nfa, a->to, okay, mark);
2984 : : }
2985 : :
2986 : : /*
2987 : : * markcanreach - recursive marking of states which can reach here
2988 : : */
2989 : : static void
2489 2990 : 863970 : markcanreach(struct nfa *nfa,
2991 : : struct state *s,
2992 : : struct state *okay, /* consider only states with this mark */
2993 : : struct state *mark) /* the value to mark with */
2994 : : {
2995 : : struct arc *a;
2996 : :
2997 : : /* Since this is recursive, it could be driven to stack overflow */
3117 2998 [ - + ]: 863970 : if (STACK_TOO_DEEP(nfa->v->re))
2999 : : {
3117 tgl@sss.pgh.pa.us 3000 [ # # ]:UBC 0 : NERR(REG_ETOOBIG);
3001 : 0 : return;
3002 : : }
3003 : :
7739 tgl@sss.pgh.pa.us 3004 [ + + ]:CBC 863970 : if (s->tmp != okay)
3005 : 553435 : return;
3006 : 310535 : s->tmp = mark;
3007 : :
3008 [ + + ]: 1156736 : for (a = s->ins; a != NULL; a = a->inchain)
3009 : 846201 : markcanreach(nfa, a->from, okay, mark);
3010 : : }
3011 : :
3012 : : /*
3013 : : * analyze - ascertain potentially-useful facts about an optimized NFA
3014 : : */
3015 : : static long /* re_info bits to be ORed in */
2489 3016 : 8886 : analyze(struct nfa *nfa)
3017 : : {
3018 : : struct arc *a;
3019 : : struct arc *aa;
3020 : :
3117 3021 [ + + ]: 8886 : if (NISERR())
3022 : 3 : return 0;
3023 : :
3024 : : /* Detect whether NFA can't match anything */
7739 3025 [ + + ]: 8883 : if (nfa->pre->outs == NULL)
3026 : 47 : return REG_UIMPOSSIBLE;
3027 : :
3028 : : /* Detect whether NFA matches all strings (possibly with length bounds) */
1149 3029 : 8836 : checkmatchall(nfa);
3030 : :
3031 : : /* Detect whether NFA can possibly match a zero-length string */
7739 3032 [ + + ]: 27202 : for (a = nfa->pre->outs; a != NULL; a = a->outchain)
3033 [ + + ]: 770128 : for (aa = a->to->outs; aa != NULL; aa = aa->outchain)
3034 [ + + ]: 751762 : if (aa->to == nfa->post)
3035 : 1067 : return REG_UEMPTYMATCH;
3036 : 7769 : return 0;
3037 : : }
3038 : :
3039 : : /*
3040 : : * checkmatchall - does the NFA represent no more than a string length test?
3041 : : *
3042 : : * If so, set nfa->minmatchall and nfa->maxmatchall correctly (they are -1
3043 : : * to begin with) and set the MATCHALL bit in nfa->flags.
3044 : : *
3045 : : * To succeed, we require all arcs to be PLAIN RAINBOW arcs, except for those
3046 : : * for pseudocolors (i.e., BOS/BOL/EOS/EOL). We must be able to reach the
3047 : : * post state via RAINBOW arcs, and if there are any loops in the graph, they
3048 : : * must be loop-to-self arcs, ensuring that each loop iteration consumes
3049 : : * exactly one character. (Longer loops are problematic because they create
3050 : : * non-consecutive possible match lengths; we have no good way to represent
3051 : : * that situation for lengths beyond the DUPINF limit.)
3052 : : *
3053 : : * Pseudocolor arcs complicate things a little. We know that they can only
3054 : : * appear as pre-state outarcs (for BOS/BOL) or post-state inarcs (for
3055 : : * EOS/EOL). There, they must exactly replicate the parallel RAINBOW arcs,
3056 : : * e.g. if the pre state has one RAINBOW outarc to state 2, it must have BOS
3057 : : * and BOL outarcs to state 2, and no others. Missing or extra pseudocolor
3058 : : * arcs can occur, meaning that the NFA involves some constraint on the
3059 : : * adjacent characters, which makes it not a matchall NFA.
3060 : : */
3061 : : static void
1149 3062 : 8836 : checkmatchall(struct nfa *nfa)
3063 : : {
3064 : : bool **haspaths;
3065 : : struct state *s;
3066 : : int i;
3067 : :
3068 : : /*
3069 : : * If there are too many states, don't bother trying to detect matchall.
3070 : : * This limit serves to bound the time and memory we could consume below.
3071 : : * Note that even if the graph is all-RAINBOW, if there are significantly
3072 : : * more than DUPINF states then it's likely that there are paths of length
3073 : : * more than DUPINF, which would force us to fail anyhow. In practice,
3074 : : * plausible ways of writing a matchall regex with maximum finite path
3075 : : * length K tend not to have very many more than K states.
3076 : : */
1077 3077 [ + + ]: 8836 : if (nfa->nstates > DUPINF * 2)
3078 : 6 : return;
3079 : :
3080 : : /*
3081 : : * First, scan all the states to verify that only RAINBOW arcs appear,
3082 : : * plus pseudocolor arcs adjacent to the pre and post states. This lets
3083 : : * us quickly eliminate most cases that aren't matchall NFAs.
3084 : : */
3085 [ + + ]: 33154 : for (s = nfa->states; s != NULL; s = s->next)
3086 : : {
3087 : : struct arc *a;
3088 : :
3089 [ + + ]: 95244 : for (a = s->outs; a != NULL; a = a->outchain)
3090 : : {
3091 [ + + ]: 70920 : if (a->type != PLAIN)
3092 : 45 : return; /* any LACONs make it non-matchall */
3093 [ + + ]: 70875 : if (a->co != RAINBOW)
3094 : : {
3095 [ + + ]: 29087 : if (nfa->cm->cd[a->co].flags & PSEUDO)
3096 : : {
3097 : : /*
3098 : : * Pseudocolor arc: verify it's in a valid place (this
3099 : : * seems quite unlikely to fail, but let's be sure).
3100 : : */
3101 [ + + ]: 21081 : if (s == nfa->pre &&
3102 [ + + + - ]: 15633 : (a->co == nfa->bos[0] || a->co == nfa->bos[1]))
3103 : : /* okay BOS/BOL arc */ ;
3104 [ + - ]: 5448 : else if (a->to == nfa->post &&
3105 [ + + + - ]: 5448 : (a->co == nfa->eos[0] || a->co == nfa->eos[1]))
3106 : : /* okay EOS/EOL arc */ ;
3107 : : else
1077 tgl@sss.pgh.pa.us 3108 :UBC 0 : return; /* unexpected pseudocolor arc */
3109 : : /* We'll check these arcs some more below. */
3110 : : }
3111 : : else
1077 tgl@sss.pgh.pa.us 3112 :CBC 8006 : return; /* any other color makes it non-matchall */
3113 : : }
3114 : : }
3115 : : /* Also, assert that the tmp fields are available for use. */
3116 [ - + ]: 24324 : assert(s->tmp == NULL);
3117 : : }
3118 : :
3119 : : /*
3120 : : * The next cheapest check we can make is to verify that the BOS/BOL
3121 : : * outarcs of the pre state reach the same states as its RAINBOW outarcs.
3122 : : * If they don't, the NFA expresses some constraints on the character
3123 : : * before the matched string, making it non-matchall. Likewise, the
3124 : : * EOS/EOL inarcs of the post state must match its RAINBOW inarcs.
3125 : : */
1149 3126 [ + + ]: 779 : if (!check_out_colors_match(nfa->pre, RAINBOW, nfa->bos[0]) ||
3127 [ + + ]: 776 : !check_out_colors_match(nfa->pre, RAINBOW, nfa->bos[1]) ||
1077 3128 [ + + ]: 606 : !check_in_colors_match(nfa->post, RAINBOW, nfa->eos[0]) ||
3129 [ + + ]: 602 : !check_in_colors_match(nfa->post, RAINBOW, nfa->eos[1]))
1149 3130 : 281 : return;
3131 : :
3132 : : /*
3133 : : * Initialize an array of path-length arrays, in which
3134 : : * checkmatchall_recurse will return per-state results. This lets us
3135 : : * memo-ize the recursive search and avoid exponential time consumption.
3136 : : */
1077 3137 : 498 : haspaths = (bool **) MALLOC(nfa->nstates * sizeof(bool *));
3138 [ - + ]: 498 : if (haspaths == NULL)
1077 tgl@sss.pgh.pa.us 3139 :UBC 0 : return; /* fail quietly */
1077 tgl@sss.pgh.pa.us 3140 :CBC 498 : memset(haspaths, 0, nfa->nstates * sizeof(bool *));
3141 : :
3142 : : /*
3143 : : * Recursively search the graph for all-RAINBOW paths to the "post" state,
3144 : : * starting at the "pre" state, and computing the lengths of the paths.
3145 : : * (Given the preceding checks, there should be at least one such path.
3146 : : * However we could get back a false result anyway, in case there are
3147 : : * multi-state loops, paths exceeding DUPINF+1 length, or non-algorithmic
3148 : : * failures such as ENOMEM.)
3149 : : */
3150 [ + + ]: 498 : if (checkmatchall_recurse(nfa, nfa->pre, haspaths))
3151 : : {
3152 : : /* The useful result is the path length array for the pre state */
3153 : 486 : bool *haspath = haspaths[nfa->pre->no];
3154 : : int minmatch,
3155 : : maxmatch,
3156 : : morematch;
3157 : :
3158 [ - + ]: 486 : assert(haspath != NULL);
3159 : :
3160 : : /*
3161 : : * haspath[] now represents the set of possible path lengths; but we
3162 : : * want to reduce that to a min and max value, because it doesn't seem
3163 : : * worth complicating regexec.c to deal with nonconsecutive possible
3164 : : * match lengths. Find min and max of first run of lengths, then
3165 : : * verify there are no nonconsecutive lengths.
3166 : : */
3167 [ + - ]: 1991 : for (minmatch = 0; minmatch <= DUPINF + 1; minmatch++)
3168 : : {
3169 [ + + ]: 1991 : if (haspath[minmatch])
3170 : 486 : break;
3171 : : }
3172 [ - + ]: 486 : assert(minmatch <= DUPINF + 1); /* else checkmatchall_recurse lied */
3173 [ + + ]: 32811 : for (maxmatch = minmatch; maxmatch < DUPINF + 1; maxmatch++)
3174 : : {
3175 [ + + ]: 32687 : if (!haspath[maxmatch + 1])
3176 : 362 : break;
3177 : : }
3178 [ + + ]: 90034 : for (morematch = maxmatch + 1; morematch <= DUPINF + 1; morematch++)
3179 : : {
3180 [ + + ]: 89554 : if (haspath[morematch])
3181 : : {
3182 : 6 : haspath = NULL; /* fail, there are nonconsecutive lengths */
3183 : 6 : break;
3184 : : }
3185 : : }
3186 : :
3187 [ + + ]: 486 : if (haspath != NULL)
3188 : : {
3189 : : /*
3190 : : * Success, so record the info. Here we have a fine point: the
3191 : : * path length from the pre state includes the pre-to-initial
3192 : : * transition, so it's one more than the actually matched string
3193 : : * length. (We avoided counting the final-to-post transition
3194 : : * within checkmatchall_recurse, but not this one.) This is why
3195 : : * checkmatchall_recurse allows one more level of path length than
3196 : : * might seem necessary. This decrement also takes care of
3197 : : * converting checkmatchall_recurse's definition of "infinity" as
3198 : : * "DUPINF+1" to our normal representation as "DUPINF".
3199 : : */
3200 [ - + ]: 480 : assert(minmatch > 0); /* else pre and post states were adjacent */
3201 : 480 : nfa->minmatchall = minmatch - 1;
3202 : 480 : nfa->maxmatchall = maxmatch - 1;
3203 : 480 : nfa->flags |= MATCHALL;
3204 : : }
3205 : : }
3206 : :
3207 : : /* Clean up */
3208 [ + + ]: 5214 : for (i = 0; i < nfa->nstates; i++)
3209 : : {
3210 [ + + ]: 4716 : if (haspaths[i] != NULL)
3211 : 4218 : FREE(haspaths[i]);
3212 : : }
3213 : 498 : FREE(haspaths);
3214 : : }
3215 : :
3216 : : /*
3217 : : * checkmatchall_recurse - recursive search for checkmatchall
3218 : : *
3219 : : * s is the state to be examined in this recursion level.
3220 : : * haspaths[] is an array of per-state exit path length arrays.
3221 : : *
3222 : : * We return true if the search was performed successfully, false if
3223 : : * we had to fail because of multi-state loops or other internal reasons.
3224 : : * (Because "dead" states that can't reach the post state have been
3225 : : * eliminated, and we already verified that only RAINBOW and matching
3226 : : * pseudocolor arcs exist, every state should have RAINBOW path(s) to
3227 : : * the post state. Hence we take a false result from recursive calls
3228 : : * as meaning that we'd better fail altogether, not just that that
3229 : : * particular state can't reach the post state.)
3230 : : *
3231 : : * On success, we store a malloc'd result array in haspaths[s->no],
3232 : : * showing the possible path lengths from s to the post state.
3233 : : * Each state's haspath[] array is of length DUPINF+2. The entries from
3234 : : * k = 0 to DUPINF are true if there is an all-RAINBOW path of length k
3235 : : * from this state to the string end. haspath[DUPINF+1] is true if all
3236 : : * path lengths >= DUPINF+1 are possible. (Situations that cannot be
3237 : : * represented under these rules cause failure.)
3238 : : *
3239 : : * checkmatchall is responsible for eventually freeing the haspath[] arrays.
3240 : : */
3241 : : static bool
3242 : 4218 : checkmatchall_recurse(struct nfa *nfa, struct state *s, bool **haspaths)
3243 : : {
1149 3244 : 4218 : bool result = false;
1077 3245 : 4218 : bool foundloop = false;
3246 : : bool *haspath;
3247 : : struct arc *a;
3248 : :
3249 : : /*
3250 : : * Since this is recursive, it could be driven to stack overflow. But we
3251 : : * need not treat that as a hard failure; just deem the NFA non-matchall.
3252 : : */
1149 3253 [ - + ]: 4218 : if (STACK_TOO_DEEP(nfa->v->re))
1149 tgl@sss.pgh.pa.us 3254 :UBC 0 : return false;
3255 : :
3256 : : /* In case the search takes a long time, check for cancel */
372 tmunro@postgresql.or 3257 [ - + ]:CBC 4218 : INTERRUPT(nfa->v->re);
3258 : :
3259 : : /* Create a haspath array for this state */
1077 tgl@sss.pgh.pa.us 3260 : 4218 : haspath = (bool *) MALLOC((DUPINF + 2) * sizeof(bool));
3261 [ - + ]: 4218 : if (haspath == NULL)
1077 tgl@sss.pgh.pa.us 3262 :UBC 0 : return false; /* again, treat as non-matchall */
1077 tgl@sss.pgh.pa.us 3263 :CBC 4218 : memset(haspath, 0, (DUPINF + 2) * sizeof(bool));
3264 : :
3265 : : /* Mark this state as being visited */
1149 3266 [ - + ]: 4218 : assert(s->tmp == NULL);
3267 : 4218 : s->tmp = s;
3268 : :
3269 [ + + ]: 41478 : for (a = s->outs; a != NULL; a = a->outchain)
3270 : : {
3271 [ + + ]: 37308 : if (a->co != RAINBOW)
3272 : 3226 : continue; /* ignore pseudocolor arcs */
3273 [ + + ]: 34082 : if (a->to == nfa->post)
3274 : : {
3275 : : /* We found an all-RAINBOW path to the post state */
3276 : 492 : result = true;
3277 : :
3278 : : /*
3279 : : * Mark this state as being zero steps away from the string end
3280 : : * (the transition to the post state isn't counted).
3281 : : */
1077 3282 : 492 : haspath[0] = true;
3283 : : }
3284 [ + + ]: 33590 : else if (a->to == s)
3285 : : {
3286 : : /* We found a cycle of length 1, which we'll deal with below. */
3287 : 127 : foundloop = true;
3288 : : }
3289 [ + + ]: 33463 : else if (a->to->tmp != NULL)
3290 : : {
3291 : : /* It's busy, so we found a cycle of length > 1, so fail. */
3292 : 6 : result = false;
3293 : 6 : break;
3294 : : }
3295 : : else
3296 : : {
3297 : : /* Consider paths forward through this to-state. */
3298 : : bool *nexthaspath;
3299 : : int i;
3300 : :
3301 : : /* If to-state was not already visited, recurse */
3302 [ + + ]: 33457 : if (haspaths[a->to->no] == NULL)
3303 : : {
3304 : 3720 : result = checkmatchall_recurse(nfa, a->to, haspaths);
3305 : : /* Fail if any recursive path fails */
3306 [ + + ]: 3720 : if (!result)
3307 : 36 : break;
3308 : : }
3309 : : else
3310 : : {
3311 : : /* The previous visit must have found path(s) to the end */
3312 : 29737 : result = true;
3313 : : }
3314 [ - + ]: 33421 : assert(a->to->tmp == NULL);
3315 : 33421 : nexthaspath = haspaths[a->to->no];
3316 [ - + ]: 33421 : assert(nexthaspath != NULL);
3317 : :
3318 : : /*
3319 : : * Now, for every path of length i from a->to to the string end,
3320 : : * there is a path of length i + 1 from s to the string end.
3321 : : */
3322 [ + + ]: 33421 : if (nexthaspath[DUPINF] != nexthaspath[DUPINF + 1])
3323 : : {
3324 : : /*
3325 : : * a->to has a path of length exactly DUPINF, but not longer;
3326 : : * or it has paths of all lengths > DUPINF but not one of
3327 : : * exactly that length. In either case, we cannot represent
3328 : : * the possible path lengths from s correctly, so fail.
3329 : : */
3330 : 6 : result = false;
3331 : 6 : break;
3332 : : }
3333 : : /* Merge knowledge of these path lengths into what we have */
3334 [ + + ]: 8587655 : for (i = 0; i < DUPINF; i++)
3335 : 8554240 : haspath[i + 1] |= nexthaspath[i];
3336 : : /* Infinity + 1 is still infinity */
3337 : 33415 : haspath[DUPINF + 1] |= nexthaspath[DUPINF + 1];
3338 : : }
3339 : : }
3340 : :
3341 [ + + + + ]: 4218 : if (result && foundloop)
3342 : : {
3343 : : /*
3344 : : * If there is a length-1 loop at this state, then find the shortest
3345 : : * known path length to the end. The loop means that every larger
3346 : : * path length is possible, too. (It doesn't matter whether any of
3347 : : * the longer lengths were already known possible.)
3348 : : */
3349 : : int i;
3350 : :
3351 [ + - ]: 160 : for (i = 0; i <= DUPINF; i++)
3352 : : {
3353 [ + + ]: 160 : if (haspath[i])
1149 3354 : 127 : break;
3355 : : }
1077 3356 [ + + ]: 32733 : for (i++; i <= DUPINF + 1; i++)
3357 : 32606 : haspath[i] = true;
3358 : : }
3359 : :
3360 : : /* Report out the completed path length map */
3361 [ - + ]: 4218 : assert(s->no < nfa->nstates);
3362 [ - + ]: 4218 : assert(haspaths[s->no] == NULL);
3363 : 4218 : haspaths[s->no] = haspath;
3364 : :
3365 : : /* Mark state no longer busy */
1149 3366 : 4218 : s->tmp = NULL;
3367 : :
3368 : 4218 : return result;
3369 : : }
3370 : :
3371 : : /*
3372 : : * check_out_colors_match - subroutine for checkmatchall
3373 : : *
3374 : : * Check whether the set of states reachable from s by arcs of color co1
3375 : : * is equivalent to the set reachable by arcs of color co2.
3376 : : * checkmatchall already verified that all of the NFA's arcs are PLAIN,
3377 : : * so we need not examine arc types here.
3378 : : */
3379 : : static bool
3380 : 1555 : check_out_colors_match(struct state *s, color co1, color co2)
3381 : : {
1077 3382 : 1555 : bool result = true;
3383 : : struct arc *a;
3384 : :
3385 : : /*
3386 : : * To do this in linear time, we assume that the NFA contains no duplicate
3387 : : * arcs. Run through the out-arcs, marking states reachable by arcs of
3388 : : * color co1. Run through again, un-marking states reachable by arcs of
3389 : : * color co2; if we see a not-marked state, we know this co2 arc is
3390 : : * unmatched. Then run through again, checking for still-marked states,
3391 : : * and in any case leaving all the tmp fields reset to NULL.
3392 : : */
3393 [ + + ]: 9493 : for (a = s->outs; a != NULL; a = a->outchain)
3394 : : {
3395 [ + + ]: 7938 : if (a->co == co1)
3396 : : {
3397 [ - + ]: 2522 : assert(a->to->tmp == NULL);
3398 : 2522 : a->to->tmp = a->to;
3399 : : }
3400 : : }
3401 [ + + ]: 9493 : for (a = s->outs; a != NULL; a = a->outchain)
3402 : : {
3403 [ + + ]: 7938 : if (a->co == co2)
3404 : : {
3405 [ + + ]: 2708 : if (a->to->tmp != NULL)
3406 : 2520 : a->to->tmp = NULL;
3407 : : else
3408 : 188 : result = false; /* unmatched co2 arc */
3409 : : }
3410 : : }
3411 [ + + ]: 9493 : for (a = s->outs; a != NULL; a = a->outchain)
3412 : : {
3413 [ + + ]: 7938 : if (a->co == co1)
3414 : : {
3415 [ + + ]: 2522 : if (a->to->tmp != NULL)
3416 : : {
3417 : 2 : result = false; /* unmatched co1 arc */
3418 : 2 : a->to->tmp = NULL;
3419 : : }
3420 : : }
3421 : : }
3422 : 1555 : return result;
3423 : : }
3424 : :
3425 : : /*
3426 : : * check_in_colors_match - subroutine for checkmatchall
3427 : : *
3428 : : * Check whether the set of states that can reach s by arcs of color co1
3429 : : * is equivalent to the set that can reach s by arcs of color co2.
3430 : : * checkmatchall already verified that all of the NFA's arcs are PLAIN,
3431 : : * so we need not examine arc types here.
3432 : : */
3433 : : static bool
1149 3434 : 1208 : check_in_colors_match(struct state *s, color co1, color co2)
3435 : : {
1077 3436 : 1208 : bool result = true;
3437 : : struct arc *a;
3438 : :
3439 : : /*
3440 : : * Identical algorithm to check_out_colors_match, except examine the
3441 : : * from-states of s' inarcs.
3442 : : */
3443 [ + + ]: 4470 : for (a = s->ins; a != NULL; a = a->inchain)
3444 : : {
3445 [ + + ]: 3262 : if (a->co == co1)
3446 : : {
3447 [ - + ]: 1012 : assert(a->from->tmp == NULL);
3448 : 1012 : a->from->tmp = a->from;
3449 : : }
3450 : : }
3451 [ + + ]: 4470 : for (a = s->ins; a != NULL; a = a->inchain)
3452 : : {
3453 [ + + ]: 3262 : if (a->co == co2)
3454 : : {
3455 [ + + ]: 1125 : if (a->from->tmp != NULL)
3456 : 1010 : a->from->tmp = NULL;
3457 : : else
3458 : 115 : result = false; /* unmatched co2 arc */
3459 : : }
3460 : : }
3461 [ + + ]: 4470 : for (a = s->ins; a != NULL; a = a->inchain)
3462 : : {
3463 [ + + ]: 3262 : if (a->co == co1)
3464 : : {
3465 [ + + ]: 1012 : if (a->from->tmp != NULL)
3466 : : {
3467 : 2 : result = false; /* unmatched co1 arc */
3468 : 2 : a->from->tmp = NULL;
3469 : : }
3470 : : }
3471 : : }
3472 : 1208 : return result;
3473 : : }
3474 : :
3475 : : /*
3476 : : * compact - construct the compact representation of an NFA
3477 : : */
3478 : : static void
2489 3479 : 8883 : compact(struct nfa *nfa,
3480 : : struct cnfa *cnfa)
3481 : : {
3482 : : struct state *s;
3483 : : struct arc *a;
3484 : : size_t nstates;
3485 : : size_t narcs;
3486 : : struct carc *ca;
3487 : : struct carc *first;
3488 : :
7559 bruce@momjian.us 3489 [ - + ]: 8883 : assert(!NISERR());
3490 : :
7739 tgl@sss.pgh.pa.us 3491 : 8883 : nstates = 0;
3492 : 8883 : narcs = 0;
7559 bruce@momjian.us 3493 [ + + ]: 118366 : for (s = nfa->states; s != NULL; s = s->next)
3494 : : {
7739 tgl@sss.pgh.pa.us 3495 : 109483 : nstates++;
3973 bruce@momjian.us 3496 : 109483 : narcs += s->nouts + 1; /* need one extra for endmarker */
3497 : : }
3498 : :
4299 tgl@sss.pgh.pa.us 3499 : 8883 : cnfa->stflags = (char *) MALLOC(nstates * sizeof(char));
7559 bruce@momjian.us 3500 : 8883 : cnfa->states = (struct carc **) MALLOC(nstates * sizeof(struct carc *));
3501 : 8883 : cnfa->arcs = (struct carc *) MALLOC(narcs * sizeof(struct carc));
4299 tgl@sss.pgh.pa.us 3502 [ + - + - : 8883 : if (cnfa->stflags == NULL || cnfa->states == NULL || cnfa->arcs == NULL)
- + ]
3503 : : {
4299 tgl@sss.pgh.pa.us 3504 [ # # ]:UBC 0 : if (cnfa->stflags != NULL)
3505 : 0 : FREE(cnfa->stflags);
7739 3506 [ # # ]: 0 : if (cnfa->states != NULL)
3507 : 0 : FREE(cnfa->states);
3508 [ # # ]: 0 : if (cnfa->arcs != NULL)
3509 : 0 : FREE(cnfa->arcs);
3510 [ # # ]: 0 : NERR(REG_ESPACE);
3511 : 0 : return;
3512 : : }
7739 tgl@sss.pgh.pa.us 3513 :CBC 8883 : cnfa->nstates = nstates;
3514 : 8883 : cnfa->pre = nfa->pre->no;
3515 : 8883 : cnfa->post = nfa->post->no;
3516 : 8883 : cnfa->bos[0] = nfa->bos[0];
3517 : 8883 : cnfa->bos[1] = nfa->bos[1];
3518 : 8883 : cnfa->eos[0] = nfa->eos[0];
3519 : 8883 : cnfa->eos[1] = nfa->eos[1];
3520 : 8883 : cnfa->ncolors = maxcolor(nfa->cm) + 1;
1149 3521 : 8883 : cnfa->flags = nfa->flags;
3522 : 8883 : cnfa->minmatchall = nfa->minmatchall;
3523 : 8883 : cnfa->maxmatchall = nfa->maxmatchall;
3524 : :
7739 3525 : 8883 : ca = cnfa->arcs;
7559 bruce@momjian.us 3526 [ + + ]: 118366 : for (s = nfa->states; s != NULL; s = s->next)
3527 : : {
3528 [ - + ]: 109483 : assert((size_t) s->no < nstates);
4299 tgl@sss.pgh.pa.us 3529 : 109483 : cnfa->stflags[s->no] = 0;
7739 3530 : 109483 : cnfa->states[s->no] = ca;
3531 : 109483 : first = ca;
3532 [ + + ]: 870887 : for (a = s->outs; a != NULL; a = a->outchain)
7559 bruce@momjian.us 3533 [ + + - ]: 761404 : switch (a->type)
3534 : : {
3535 : 761305 : case PLAIN:
3536 : 761305 : ca->co = a->co;
3537 : 761305 : ca->to = a->to->no;
3538 : 761305 : ca++;
3539 : 761305 : break;
3540 : 99 : case LACON:
3541 [ - + ]: 99 : assert(s->no != cnfa->pre);
1149 tgl@sss.pgh.pa.us 3542 [ - + ]: 99 : assert(a->co >= 0);
7559 bruce@momjian.us 3543 : 99 : ca->co = (color) (cnfa->ncolors + a->co);
3544 : 99 : ca->to = a->to->no;
3545 : 99 : ca++;
3546 : 99 : cnfa->flags |= HASLACONS;
3547 : 99 : break;
7559 bruce@momjian.us 3548 :UBC 0 : default:
3103 tgl@sss.pgh.pa.us 3549 [ # # ]: 0 : NERR(REG_ASSERT);
1152 3550 : 0 : return;
3551 : : }
3103 tgl@sss.pgh.pa.us 3552 :CBC 109483 : carcsort(first, ca - first);
7739 3553 : 109483 : ca->co = COLORLESS;
3554 : 109483 : ca->to = 0;
3555 : 109483 : ca++;
3556 : : }
3557 [ - + ]: 8883 : assert(ca == &cnfa->arcs[narcs]);
3558 [ - + ]: 8883 : assert(cnfa->nstates != 0);
3559 : :
3560 : : /* mark no-progress states */
3561 [ + + ]: 38295 : for (a = nfa->pre->outs; a != NULL; a = a->outchain)
4299 3562 : 29412 : cnfa->stflags[a->to->no] = CNFA_NOPROGRESS;
3563 : 8883 : cnfa->stflags[nfa->pre->no] = CNFA_NOPROGRESS;
3564 : : }
3565 : :
3566 : : /*
3567 : : * carcsort - sort compacted-NFA arcs by color
3568 : : */
3569 : : static void
2489 3570 : 109483 : carcsort(struct carc *first, size_t n)
3571 : : {
3103 3572 [ + + ]: 109483 : if (n > 1)
3573 : 21978 : qsort(first, n, sizeof(struct carc), carc_cmp);
3574 : 109483 : }
3575 : :
3576 : : static int
3577 : 7720646 : carc_cmp(const void *a, const void *b)
3578 : : {
3579 : 7720646 : const struct carc *aa = (const struct carc *) a;
3580 : 7720646 : const struct carc *bb = (const struct carc *) b;
3581 : :
3582 [ + + ]: 7720646 : if (aa->co < bb->co)
3583 : 68468 : return -1;
3584 [ + + ]: 7652178 : if (aa->co > bb->co)
3585 : 97281 : return +1;
3586 [ + + ]: 7554897 : if (aa->to < bb->to)
3587 : 5181357 : return -1;
3588 [ + - ]: 2373540 : if (aa->to > bb->to)
3589 : 2373540 : return +1;
3590 : : /* This is unreached, since there should be no duplicate arcs now: */
3103 tgl@sss.pgh.pa.us 3591 :UBC 0 : return 0;
3592 : : }
3593 : :
3594 : : /*
3595 : : * freecnfa - free a compacted NFA
3596 : : */
3597 : : static void
2489 tgl@sss.pgh.pa.us 3598 :CBC 2144 : freecnfa(struct cnfa *cnfa)
3599 : : {
1155 3600 [ - + ]: 2144 : assert(!NULLCNFA(*cnfa)); /* not empty already */
4299 3601 : 2144 : FREE(cnfa->stflags);
7739 3602 : 2144 : FREE(cnfa->states);
3603 : 2144 : FREE(cnfa->arcs);
1155 3604 : 2144 : ZAPCNFA(*cnfa);
7739 3605 : 2144 : }
3606 : :
3607 : : /*
3608 : : * dumpnfa - dump an NFA in human-readable form
3609 : : */
3610 : : static void
2489 tgl@sss.pgh.pa.us 3611 :UBC 0 : dumpnfa(struct nfa *nfa,
3612 : : FILE *f)
3613 : : {
3614 : : #ifdef REG_DEBUG
3615 : : struct state *s;
3616 : : int nstates = 0;
3617 : : int narcs = 0;
3618 : :
3619 : : fprintf(f, "pre %d, post %d", nfa->pre->no, nfa->post->no);
3620 : : if (nfa->bos[0] != COLORLESS)
3621 : : fprintf(f, ", bos [%ld]", (long) nfa->bos[0]);
3622 : : if (nfa->bos[1] != COLORLESS)
3623 : : fprintf(f, ", bol [%ld]", (long) nfa->bos[1]);
3624 : : if (nfa->eos[0] != COLORLESS)
3625 : : fprintf(f, ", eos [%ld]", (long) nfa->eos[0]);
3626 : : if (nfa->eos[1] != COLORLESS)
3627 : : fprintf(f, ", eol [%ld]", (long) nfa->eos[1]);
3628 : : if (nfa->flags & HASLACONS)
3629 : : fprintf(f, ", haslacons");
3630 : : if (nfa->flags & MATCHALL)
3631 : : {
3632 : : fprintf(f, ", minmatchall %d", nfa->minmatchall);
3633 : : if (nfa->maxmatchall == DUPINF)
3634 : : fprintf(f, ", maxmatchall inf");
3635 : : else
3636 : : fprintf(f, ", maxmatchall %d", nfa->maxmatchall);
3637 : : }
3638 : : fprintf(f, "\n");
3639 : : for (s = nfa->states; s != NULL; s = s->next)
3640 : : {
3641 : : dumpstate(s, f);
3642 : : nstates++;
3643 : : narcs += s->nouts;
3644 : : }
3645 : : fprintf(f, "total of %d states, %d arcs\n", nstates, narcs);
3646 : : if (nfa->parent == NULL)
3647 : : dumpcolors(nfa->cm, f);
3648 : : fflush(f);
3649 : : #endif
7739 3650 : 0 : }
3651 : :
3652 : : #ifdef REG_DEBUG /* subordinates of dumpnfa */
3653 : :
3654 : : /*
3655 : : * dumpstate - dump an NFA state in human-readable form
3656 : : */
3657 : : static void
3658 : : dumpstate(struct state *s,
3659 : : FILE *f)
3660 : : {
3661 : : struct arc *a;
3662 : :
3663 : : fprintf(f, "%d%s%c", s->no, (s->tmp != NULL) ? "T" : "",
3664 : : (s->flag) ? s->flag : '.');
3665 : : if (s->prev != NULL && s->prev->next != s)
3666 : : fprintf(f, "\tstate chain bad\n");
3667 : : if (s->nouts == 0)
3668 : : fprintf(f, "\tno out arcs\n");
3669 : : else
3670 : : dumparcs(s, f);
3671 : : for (a = s->ins; a != NULL; a = a->inchain)
3672 : : {
3673 : : if (a->to != s)
3674 : : fprintf(f, "\tlink from %d to %d on %d's in-chain\n",
3675 : : a->from->no, a->to->no, s->no);
3676 : : }
3677 : : fflush(f);
3678 : : }
3679 : :
3680 : : /*
3681 : : * dumparcs - dump out-arcs in human-readable form
3682 : : */
3683 : : static void
3684 : : dumparcs(struct state *s,
3685 : : FILE *f)
3686 : : {
3687 : : int pos;
3688 : : struct arc *a;
3689 : :
3690 : : /* printing oldest arcs first is usually clearer */
3691 : : a = s->outs;
3692 : : assert(a != NULL);
3693 : : while (a->outchain != NULL)
3694 : : a = a->outchain;
3695 : : pos = 1;
3696 : : do
3697 : : {
3698 : : dumparc(a, s, f);
3699 : : if (pos == 5)
3700 : : {
3701 : : fprintf(f, "\n");
3702 : : pos = 1;
3703 : : }
3704 : : else
3705 : : pos++;
3706 : : a = a->outchainRev;
3707 : : } while (a != NULL);
3708 : : if (pos != 1)
3709 : : fprintf(f, "\n");
3710 : : }
3711 : :
3712 : : /*
3713 : : * dumparc - dump one outarc in readable form, including prefixing tab
3714 : : */
3715 : : static void
3716 : : dumparc(struct arc *a,
3717 : : struct state *s,
3718 : : FILE *f)
3719 : : {
3720 : : struct arc *aa;
3721 : :
3722 : : fprintf(f, "\t");
3723 : : switch (a->type)
3724 : : {
3725 : : case PLAIN:
3726 : : if (a->co == RAINBOW)
3727 : : fprintf(f, "[*]");
3728 : : else
3729 : : fprintf(f, "[%ld]", (long) a->co);
3730 : : break;
3731 : : case AHEAD:
3732 : : if (a->co == RAINBOW)
3733 : : fprintf(f, ">*>");
3734 : : else
3735 : : fprintf(f, ">%ld>", (long) a->co);
3736 : : break;
3737 : : case BEHIND:
3738 : : if (a->co == RAINBOW)
3739 : : fprintf(f, "<*<");
3740 : : else
3741 : : fprintf(f, "<%ld<", (long) a->co);
3742 : : break;
3743 : : case LACON:
3744 : : fprintf(f, ":%ld:", (long) a->co);
3745 : : break;
3746 : : case '^':
3747 : : case '$':
3748 : : fprintf(f, "%c%d", a->type, (int) a->co);
3749 : : break;
3750 : : case EMPTY:
3751 : : break;
3752 : : default:
3753 : : fprintf(f, "0x%x/0%lo", a->type, (long) a->co);
3754 : : break;
3755 : : }
3756 : : if (a->from != s)
3757 : : fprintf(f, "?%d?", a->from->no);
3758 : : for (aa = a->from->outs; aa != NULL; aa = aa->outchain)
3759 : : if (aa == a)
3760 : : break; /* NOTE BREAK OUT */
3761 : : if (aa == NULL)
3762 : : fprintf(f, "?!?"); /* missing from out-chain */
3763 : : fprintf(f, "->");
3764 : : if (a->to == NULL)
3765 : : {
3766 : : fprintf(f, "NULL");
3767 : : return;
3768 : : }
3769 : : fprintf(f, "%d", a->to->no);
3770 : : for (aa = a->to->ins; aa != NULL; aa = aa->inchain)
3771 : : if (aa == a)
3772 : : break; /* NOTE BREAK OUT */
3773 : : if (aa == NULL)
3774 : : fprintf(f, "?!?"); /* missing from in-chain */
3775 : : }
3776 : : #endif /* REG_DEBUG */
3777 : :
3778 : : /*
3779 : : * dumpcnfa - dump a compacted NFA in human-readable form
3780 : : */
3781 : : #ifdef REG_DEBUG
3782 : : static void
3783 : : dumpcnfa(struct cnfa *cnfa,
3784 : : FILE *f)
3785 : : {
3786 : : int st;
3787 : :
3788 : : fprintf(f, "pre %d, post %d", cnfa->pre, cnfa->post);
3789 : : if (cnfa->bos[0] != COLORLESS)
3790 : : fprintf(f, ", bos [%ld]", (long) cnfa->bos[0]);
3791 : : if (cnfa->bos[1] != COLORLESS)
3792 : : fprintf(f, ", bol [%ld]", (long) cnfa->bos[1]);
3793 : : if (cnfa->eos[0] != COLORLESS)
3794 : : fprintf(f, ", eos [%ld]", (long) cnfa->eos[0]);
3795 : : if (cnfa->eos[1] != COLORLESS)
3796 : : fprintf(f, ", eol [%ld]", (long) cnfa->eos[1]);
3797 : : if (cnfa->flags & HASLACONS)
3798 : : fprintf(f, ", haslacons");
3799 : : if (cnfa->flags & MATCHALL)
3800 : : {
3801 : : fprintf(f, ", minmatchall %d", cnfa->minmatchall);
3802 : : if (cnfa->maxmatchall == DUPINF)
3803 : : fprintf(f, ", maxmatchall inf");
3804 : : else
3805 : : fprintf(f, ", maxmatchall %d", cnfa->maxmatchall);
3806 : : }
3807 : : fprintf(f, "\n");
3808 : : for (st = 0; st < cnfa->nstates; st++)
3809 : : dumpcstate(st, cnfa, f);
3810 : : fflush(f);
3811 : : }
3812 : : #endif
3813 : :
3814 : : #ifdef REG_DEBUG /* subordinates of dumpcnfa */
3815 : :
3816 : : /*
3817 : : * dumpcstate - dump a compacted-NFA state in human-readable form
3818 : : */
3819 : : static void
3820 : : dumpcstate(int st,
3821 : : struct cnfa *cnfa,
3822 : : FILE *f)
3823 : : {
3824 : : struct carc *ca;
3825 : : int pos;
3826 : :
3827 : : fprintf(f, "%d%s", st, (cnfa->stflags[st] & CNFA_NOPROGRESS) ? ":" : ".");
3828 : : pos = 1;
3829 : : for (ca = cnfa->states[st]; ca->co != COLORLESS; ca++)
3830 : : {
3831 : : if (ca->co == RAINBOW)
3832 : : fprintf(f, "\t[*]->%d", ca->to);
3833 : : else if (ca->co < cnfa->ncolors)
3834 : : fprintf(f, "\t[%ld]->%d", (long) ca->co, ca->to);
3835 : : else
3836 : : fprintf(f, "\t:%ld:->%d", (long) (ca->co - cnfa->ncolors), ca->to);
3837 : : if (pos == 5)
3838 : : {
3839 : : fprintf(f, "\n");
3840 : : pos = 1;
3841 : : }
3842 : : else
3843 : : pos++;
3844 : : }
3845 : : if (ca == cnfa->states[st] || pos != 1)
3846 : : fprintf(f, "\n");
3847 : : fflush(f);
3848 : : }
3849 : :
3850 : : #endif /* REG_DEBUG */
|
