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Fixed wxRichTextCtrl caret test case
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1 /*
2 * DFA routines
3 * This file is #included by regexec.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 */
32
33 /*
34 - longest - longest-preferred matching engine
35 ^ static chr *longest(struct vars *, struct dfa *, chr *, chr *, int *);
36 */
37 static chr * /* endpoint, or NULL */
38 longest(v, d, start, stop, hitstopp)
39 struct vars *v; /* used only for debug and exec flags */
40 struct dfa *d;
41 chr *start; /* where the match should start */
42 chr *stop; /* match must end at or before here */
43 int *hitstopp; /* record whether hit v->stop, if non-NULL */
44 {
45 chr *cp;
46 chr *realstop = (stop == v->stop) ? stop : stop + 1;
47 color co;
48 struct sset *css;
49 struct sset *ss;
50 chr *post;
51 int i;
52 struct colormap *cm = d->cm;
53
54 /* initialize */
55 css = initialize(v, d, start);
56 cp = start;
57 if (hitstopp != NULL)
58 *hitstopp = 0;
59
60 /* startup */
61 FDEBUG(("+++ startup +++\n"));
62 if (cp == v->start) {
63 co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];
64 FDEBUG(("color %ld\n", (long)co));
65 } else {
66 co = GETCOLOR(cm, *(cp - 1));
67 FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));
68 }
69 css = miss(v, d, css, co, cp, start);
70 if (css == NULL)
71 return NULL;
72 css->lastseen = cp;
73
74 /* main loop */
75 if (v->eflags&REG_FTRACE)
76 while (cp < realstop) {
77 FDEBUG(("+++ at c%d +++\n", css - d->ssets));
78 co = GETCOLOR(cm, *cp);
79 FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));
80 ss = css->outs[co];
81 if (ss == NULL) {
82 ss = miss(v, d, css, co, cp+1, start);
83 if (ss == NULL)
84 break; /* NOTE BREAK OUT */
85 }
86 cp++;
87 ss->lastseen = cp;
88 css = ss;
89 }
90 else
91 while (cp < realstop) {
92 co = GETCOLOR(cm, *cp);
93 ss = css->outs[co];
94 if (ss == NULL) {
95 ss = miss(v, d, css, co, cp+1, start);
96 if (ss == NULL)
97 break; /* NOTE BREAK OUT */
98 }
99 cp++;
100 ss->lastseen = cp;
101 css = ss;
102 }
103
104 /* shutdown */
105 FDEBUG(("+++ shutdown at c%d +++\n", css - d->ssets));
106 if (cp == v->stop && stop == v->stop) {
107 if (hitstopp != NULL)
108 *hitstopp = 1;
109 co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];
110 FDEBUG(("color %ld\n", (long)co));
111 ss = miss(v, d, css, co, cp, start);
112 /* special case: match ended at eol? */
113 if (ss != NULL && (ss->flags&POSTSTATE))
114 return cp;
115 else if (ss != NULL)
116 ss->lastseen = cp; /* to be tidy */
117 }
118
119 /* find last match, if any */
120 post = d->lastpost;
121 for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)
122 if ((ss->flags&POSTSTATE) && post != ss->lastseen &&
123 (post == NULL || post < ss->lastseen))
124 post = ss->lastseen;
125 if (post != NULL) /* found one */
126 return post - 1;
127
128 return NULL;
129 }
130
131 /*
132 - shortest - shortest-preferred matching engine
133 ^ static chr *shortest(struct vars *, struct dfa *, chr *, chr *, chr *,
134 ^ chr **, int *);
135 */
136 static chr * /* endpoint, or NULL */
137 shortest(v, d, start, min, max, coldp, hitstopp)
138 struct vars *v;
139 struct dfa *d;
140 chr *start; /* where the match should start */
141 chr *min; /* match must end at or after here */
142 chr *max; /* match must end at or before here */
143 chr **coldp; /* store coldstart pointer here, if nonNULL */
144 int *hitstopp; /* record whether hit v->stop, if non-NULL */
145 {
146 chr *cp;
147 chr *realmin = (min == v->stop) ? min : min + 1;
148 chr *realmax = (max == v->stop) ? max : max + 1;
149 color co;
150 struct sset *css;
151 struct sset *ss;
152 struct colormap *cm = d->cm;
153
154 /* initialize */
155 css = initialize(v, d, start);
156 cp = start;
157 if (hitstopp != NULL)
158 *hitstopp = 0;
159
160 /* startup */
161 FDEBUG(("--- startup ---\n"));
162 if (cp == v->start) {
163 co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];
164 FDEBUG(("color %ld\n", (long)co));
165 } else {
166 co = GETCOLOR(cm, *(cp - 1));
167 FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));
168 }
169 css = miss(v, d, css, co, cp, start);
170 if (css == NULL)
171 return NULL;
172 css->lastseen = cp;
173 ss = css;
174
175 /* main loop */
176 if (v->eflags&REG_FTRACE)
177 while (cp < realmax) {
178 FDEBUG(("--- at c%d ---\n", css - d->ssets));
179 co = GETCOLOR(cm, *cp);
180 FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));
181 ss = css->outs[co];
182 if (ss == NULL) {
183 ss = miss(v, d, css, co, cp+1, start);
184 if (ss == NULL)
185 break; /* NOTE BREAK OUT */
186 }
187 cp++;
188 ss->lastseen = cp;
189 css = ss;
190 if ((ss->flags&POSTSTATE) && cp >= realmin)
191 break; /* NOTE BREAK OUT */
192 }
193 else
194 while (cp < realmax) {
195 co = GETCOLOR(cm, *cp);
196 ss = css->outs[co];
197 if (ss == NULL) {
198 ss = miss(v, d, css, co, cp+1, start);
199 if (ss == NULL)
200 break; /* NOTE BREAK OUT */
201 }
202 cp++;
203 ss->lastseen = cp;
204 css = ss;
205 if ((ss->flags&POSTSTATE) && cp >= realmin)
206 break; /* NOTE BREAK OUT */
207 }
208
209 if (ss == NULL)
210 return NULL;
211
212 if (coldp != NULL) /* report last no-progress state set, if any */
213 *coldp = lastcold(v, d);
214
215 if ((ss->flags&POSTSTATE) && cp > min) {
216 assert(cp >= realmin);
217 cp--;
218 } else if (cp == v->stop && max == v->stop) {
219 co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];
220 FDEBUG(("color %ld\n", (long)co));
221 ss = miss(v, d, css, co, cp, start);
222 /* match might have ended at eol */
223 if ((ss == NULL || !(ss->flags&POSTSTATE)) && hitstopp != NULL)
224 *hitstopp = 1;
225 }
226
227 if (ss == NULL || !(ss->flags&POSTSTATE))
228 return NULL;
229
230 return cp;
231 }
232
233 /*
234 - lastcold - determine last point at which no progress had been made
235 ^ static chr *lastcold(struct vars *, struct dfa *);
236 */
237 static chr * /* endpoint, or NULL */
238 lastcold(v, d)
239 struct vars *v;
240 struct dfa *d;
241 {
242 struct sset *ss;
243 chr *nopr;
244 int i;
245
246 nopr = d->lastnopr;
247 if (nopr == NULL)
248 nopr = v->start;
249 for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)
250 if ((ss->flags&NOPROGRESS) && nopr < ss->lastseen)
251 nopr = ss->lastseen;
252 return nopr;
253 }
254
255 /*
256 - newdfa - set up a fresh DFA
257 ^ static struct dfa *newdfa(struct vars *, struct cnfa *,
258 ^ struct colormap *, struct smalldfa *);
259 */
260
261 /* FIXME Required for CW 8 on Mac since it's not in limits.h */
262 #ifndef __CHAR_BIT__
263 #define __CHAR_BIT__ 8
264 #endif
265
266 static struct dfa *
267 newdfa(v, cnfa, cm, small)
268 struct vars *v;
269 struct cnfa *cnfa;
270 struct colormap *cm;
271 struct smalldfa *small; /* preallocated space, may be NULL */
272 {
273 struct dfa *d;
274 size_t nss = cnfa->nstates * 2;
275 int wordsper = (cnfa->nstates + UBITS - 1) / UBITS;
276 struct smalldfa *smallwas = small;
277
278 assert(cnfa != NULL && cnfa->nstates != 0);
279
280 if (nss <= FEWSTATES && cnfa->ncolors <= FEWCOLORS) {
281 assert(wordsper == 1);
282 if (small == NULL) {
283 small = (struct smalldfa *)MALLOC(
284 sizeof(struct smalldfa));
285 if (small == NULL) {
286 ERR(REG_ESPACE);
287 return NULL;
288 }
289 }
290 d = &small->dfa;
291 d->ssets = small->ssets;
292 d->statesarea = small->statesarea;
293 d->work = &d->statesarea[nss];
294 d->outsarea = small->outsarea;
295 d->incarea = small->incarea;
296 d->cptsmalloced = 0;
297 d->mallocarea = (smallwas == NULL) ? (char *)small : NULL;
298 } else {
299 d = (struct dfa *)MALLOC(sizeof(struct dfa));
300 if (d == NULL) {
301 ERR(REG_ESPACE);
302 return NULL;
303 }
304 d->ssets = (struct sset *)MALLOC(nss * sizeof(struct sset));
305 d->statesarea = (unsigned *)MALLOC((nss+WORK) * wordsper *
306 sizeof(unsigned));
307 d->work = &d->statesarea[nss * wordsper];
308 d->outsarea = (struct sset **)MALLOC(nss * cnfa->ncolors *
309 sizeof(struct sset *));
310 d->incarea = (struct arcp *)MALLOC(nss * cnfa->ncolors *
311 sizeof(struct arcp));
312 d->cptsmalloced = 1;
313 d->mallocarea = (char *)d;
314 if (d->ssets == NULL || d->statesarea == NULL ||
315 d->outsarea == NULL || d->incarea == NULL) {
316 freedfa(d);
317 ERR(REG_ESPACE);
318 return NULL;
319 }
320 }
321
322 d->nssets = (v->eflags&REG_SMALL) ? 7 : nss;
323 d->nssused = 0;
324 d->nstates = cnfa->nstates;
325 d->ncolors = cnfa->ncolors;
326 d->wordsper = wordsper;
327 d->cnfa = cnfa;
328 d->cm = cm;
329 d->lastpost = NULL;
330 d->lastnopr = NULL;
331 d->search = d->ssets;
332
333 /* initialization of sset fields is done as needed */
334
335 return d;
336 }
337
338 /*
339 - freedfa - free a DFA
340 ^ static VOID freedfa(struct dfa *);
341 */
342 static VOID
343 freedfa(d)
344 struct dfa *d;
345 {
346 if (d->cptsmalloced) {
347 if (d->ssets != NULL)
348 FREE(d->ssets);
349 if (d->statesarea != NULL)
350 FREE(d->statesarea);
351 if (d->outsarea != NULL)
352 FREE(d->outsarea);
353 if (d->incarea != NULL)
354 FREE(d->incarea);
355 }
356
357 if (d->mallocarea != NULL)
358 FREE(d->mallocarea);
359 }
360
361 /*
362 - hash - construct a hash code for a bitvector
363 * There are probably better ways, but they're more expensive.
364 ^ static unsigned hash(unsigned *, int);
365 */
366 static unsigned
367 hash(uv, n)
368 unsigned *uv;
369 int n;
370 {
371 int i;
372 unsigned h;
373
374 h = 0;
375 for (i = 0; i < n; i++)
376 h ^= uv[i];
377 return h;
378 }
379
380 /*
381 - initialize - hand-craft a cache entry for startup, otherwise get ready
382 ^ static struct sset *initialize(struct vars *, struct dfa *, chr *);
383 */
384 static struct sset *
385 initialize(v, d, start)
386 struct vars *v; /* used only for debug flags */
387 struct dfa *d;
388 chr *start;
389 {
390 struct sset *ss;
391 int i;
392
393 /* is previous one still there? */
394 if (d->nssused > 0 && (d->ssets[0].flags&STARTER))
395 ss = &d->ssets[0];
396 else { /* no, must (re)build it */
397 ss = getvacant(v, d, start, start);
398 for (i = 0; i < d->wordsper; i++)
399 ss->states[i] = 0;
400 BSET(ss->states, d->cnfa->pre);
401 ss->hash = HASH(ss->states, d->wordsper);
402 assert(d->cnfa->pre != d->cnfa->post);
403 ss->flags = STARTER|LOCKED|NOPROGRESS;
404 /* lastseen dealt with below */
405 }
406
407 for (i = 0; i < d->nssused; i++)
408 d->ssets[i].lastseen = NULL;
409 ss->lastseen = start; /* maybe untrue, but harmless */
410 d->lastpost = NULL;
411 d->lastnopr = NULL;
412 return ss;
413 }
414
415 /*
416 - miss - handle a cache miss
417 ^ static struct sset *miss(struct vars *, struct dfa *, struct sset *,
418 ^ pcolor, chr *, chr *);
419 */
420 static struct sset * /* NULL if goes to empty set */
421 miss(v, d, css, co, cp, start)
422 struct vars *v; /* used only for debug flags */
423 struct dfa *d;
424 struct sset *css;
425 pcolor co;
426 chr *cp; /* next chr */
427 chr *start; /* where the attempt got started */
428 {
429 struct cnfa *cnfa = d->cnfa;
430 int i;
431 unsigned h;
432 struct carc *ca;
433 struct sset *p;
434 int ispost;
435 int noprogress;
436 int gotstate;
437 int dolacons;
438 int sawlacons;
439
440 /* for convenience, we can be called even if it might not be a miss */
441 if (css->outs[co] != NULL) {
442 FDEBUG(("hit\n"));
443 return css->outs[co];
444 }
445 FDEBUG(("miss\n"));
446
447 /* first, what set of states would we end up in? */
448 for (i = 0; i < d->wordsper; i++)
449 d->work[i] = 0;
450 ispost = 0;
451 noprogress = 1;
452 gotstate = 0;
453 for (i = 0; i < d->nstates; i++)
454 if (ISBSET(css->states, i))
455 for (ca = cnfa->states[i]+1; ca->co != COLORLESS; ca++)
456 if (ca->co == co) {
457 BSET(d->work, ca->to);
458 gotstate = 1;
459 if (ca->to == cnfa->post)
460 ispost = 1;
461 if (!cnfa->states[ca->to]->co)
462 noprogress = 0;
463 FDEBUG(("%d -> %d\n", i, ca->to));
464 }
465 dolacons = (gotstate) ? (cnfa->flags&HASLACONS) : 0;
466 sawlacons = 0;
467 while (dolacons) { /* transitive closure */
468 dolacons = 0;
469 for (i = 0; i < d->nstates; i++)
470 if (ISBSET(d->work, i))
471 for (ca = cnfa->states[i]+1; ca->co != COLORLESS;
472 ca++) {
473 if (ca->co <= cnfa->ncolors)
474 continue; /* NOTE CONTINUE */
475 sawlacons = 1;
476 if (ISBSET(d->work, ca->to))
477 continue; /* NOTE CONTINUE */
478 if (!lacon(v, cnfa, cp, ca->co))
479 continue; /* NOTE CONTINUE */
480 BSET(d->work, ca->to);
481 dolacons = 1;
482 if (ca->to == cnfa->post)
483 ispost = 1;
484 if (!cnfa->states[ca->to]->co)
485 noprogress = 0;
486 FDEBUG(("%d :> %d\n", i, ca->to));
487 }
488 }
489 if (!gotstate)
490 return NULL;
491 h = HASH(d->work, d->wordsper);
492
493 /* next, is that in the cache? */
494 for (p = d->ssets, i = d->nssused; i > 0; p++, i--)
495 if (HIT(h, d->work, p, d->wordsper)) {
496 FDEBUG(("cached c%d\n", p - d->ssets));
497 break; /* NOTE BREAK OUT */
498 }
499 if (i == 0) { /* nope, need a new cache entry */
500 p = getvacant(v, d, cp, start);
501 assert(p != css);
502 for (i = 0; i < d->wordsper; i++)
503 p->states[i] = d->work[i];
504 p->hash = h;
505 p->flags = (ispost) ? POSTSTATE : 0;
506 if (noprogress)
507 p->flags |= NOPROGRESS;
508 /* lastseen to be dealt with by caller */
509 }
510
511 if (!sawlacons) { /* lookahead conds. always cache miss */
512 FDEBUG(("c%d[%d]->c%d\n", css - d->ssets, co, p - d->ssets));
513 css->outs[co] = p;
514 css->inchain[co] = p->ins;
515 p->ins.ss = css;
516 p->ins.co = (color)co;
517 }
518 return p;
519 }
520
521 /*
522 - lacon - lookahead-constraint checker for miss()
523 ^ static int lacon(struct vars *, struct cnfa *, chr *, pcolor);
524 */
525 static int /* predicate: constraint satisfied? */
526 lacon(v, pcnfa, cp, co)
527 struct vars *v;
528 struct cnfa *pcnfa; /* parent cnfa */
529 chr *cp;
530 pcolor co; /* "color" of the lookahead constraint */
531 {
532 int n;
533 struct subre *sub;
534 struct dfa *d;
535 struct smalldfa sd;
536 chr *end;
537
538 n = co - pcnfa->ncolors;
539 assert(n < v->g->nlacons && v->g->lacons != NULL);
540 FDEBUG(("=== testing lacon %d\n", n));
541 sub = &v->g->lacons[n];
542 d = newdfa(v, &sub->cnfa, &v->g->cmap, &sd);
543 if (d == NULL) {
544 ERR(REG_ESPACE);
545 return 0;
546 }
547 end = longest(v, d, cp, v->stop, (int *)NULL);
548 freedfa(d);
549 FDEBUG(("=== lacon %d match %d\n", n, (end != NULL)));
550 return (sub->subno) ? (end != NULL) : (end == NULL);
551 }
552
553 /*
554 - getvacant - get a vacant state set
555 * This routine clears out the inarcs and outarcs, but does not otherwise
556 * clear the innards of the state set -- that's up to the caller.
557 ^ static struct sset *getvacant(struct vars *, struct dfa *, chr *, chr *);
558 */
559 static struct sset *
560 getvacant(v, d, cp, start)
561 struct vars *v; /* used only for debug flags */
562 struct dfa *d;
563 chr *cp;
564 chr *start;
565 {
566 int i;
567 struct sset *ss;
568 struct sset *p;
569 struct arcp ap;
570 struct arcp lastap;
571 color co;
572 lastap.ss = NULL; lastap.co = 0; // WX: suppress dummy gcc warnings
573 ss = pickss(v, d, cp, start);
574 assert(!(ss->flags&LOCKED));
575
576 /* clear out its inarcs, including self-referential ones */
577 ap = ss->ins;
578 while ((p = ap.ss) != NULL) {
579 co = ap.co;
580 FDEBUG(("zapping c%d's %ld outarc\n", p - d->ssets, (long)co));
581 p->outs[co] = NULL;
582 ap = p->inchain[co];
583 p->inchain[co].ss = NULL; /* paranoia */
584 }
585 ss->ins.ss = NULL;
586
587 /* take it off the inarc chains of the ssets reached by its outarcs */
588 for (i = 0; i < d->ncolors; i++) {
589 p = ss->outs[i];
590 assert(p != ss); /* not self-referential */
591 if (p == NULL)
592 continue; /* NOTE CONTINUE */
593 FDEBUG(("del outarc %d from c%d's in chn\n", i, p - d->ssets));
594 if (p->ins.ss == ss && p->ins.co == i)
595 p->ins = ss->inchain[i];
596 else {
597 assert(p->ins.ss != NULL);
598 for (ap = p->ins; ap.ss != NULL &&
599 !(ap.ss == ss && ap.co == i);
600 ap = ap.ss->inchain[ap.co])
601 lastap = ap;
602 assert(ap.ss != NULL);
603 lastap.ss->inchain[lastap.co] = ss->inchain[i];
604 }
605 ss->outs[i] = NULL;
606 ss->inchain[i].ss = NULL;
607 }
608
609 /* if ss was a success state, may need to remember location */
610 if ((ss->flags&POSTSTATE) && ss->lastseen != d->lastpost &&
611 (d->lastpost == NULL || d->lastpost < ss->lastseen))
612 d->lastpost = ss->lastseen;
613
614 /* likewise for a no-progress state */
615 if ((ss->flags&NOPROGRESS) && ss->lastseen != d->lastnopr &&
616 (d->lastnopr == NULL || d->lastnopr < ss->lastseen))
617 d->lastnopr = ss->lastseen;
618
619 return ss;
620 }
621
622 /*
623 - pickss - pick the next stateset to be used
624 ^ static struct sset *pickss(struct vars *, struct dfa *, chr *, chr *);
625 */
626 static struct sset *
627 pickss(v, d, cp, start)
628 struct vars *v; /* used only for debug flags */
629 struct dfa *d;
630 chr *cp;
631 chr *start;
632 {
633 int i;
634 struct sset *ss;
635 struct sset *end;
636 chr *ancient;
637
638 /* shortcut for cases where cache isn't full */
639 if (d->nssused < d->nssets) {
640 i = d->nssused;
641 d->nssused++;
642 ss = &d->ssets[i];
643 FDEBUG(("new c%d\n", i));
644 /* set up innards */
645 ss->states = &d->statesarea[i * d->wordsper];
646 ss->flags = 0;
647 ss->ins.ss = NULL;
648 ss->ins.co = WHITE; /* give it some value */
649 ss->outs = &d->outsarea[i * d->ncolors];
650 ss->inchain = &d->incarea[i * d->ncolors];
651 for (i = 0; i < d->ncolors; i++) {
652 ss->outs[i] = NULL;
653 ss->inchain[i].ss = NULL;
654 }
655 return ss;
656 }
657
658 /* look for oldest, or old enough anyway */
659 if (cp - start > d->nssets*2/3) /* oldest 33% are expendable */
660 ancient = cp - d->nssets*2/3;
661 else
662 ancient = start;
663 for (ss = d->search, end = &d->ssets[d->nssets]; ss < end; ss++)
664 if ((ss->lastseen == NULL || ss->lastseen < ancient) &&
665 !(ss->flags&LOCKED)) {
666 d->search = ss + 1;
667 FDEBUG(("replacing c%d\n", ss - d->ssets));
668 return ss;
669 }
670 for (ss = d->ssets, end = d->search; ss < end; ss++)
671 if ((ss->lastseen == NULL || ss->lastseen < ancient) &&
672 !(ss->flags&LOCKED)) {
673 d->search = ss + 1;
674 FDEBUG(("replacing c%d\n", ss - d->ssets));
675 return ss;
676 }
677
678 /* nobody's old enough?!? -- something's really wrong */
679 FDEBUG(("can't find victim to replace!\n"));
680 assert(NOTREACHED);
681 ERR(REG_ASSERT);
682 return d->ssets;
683 }