Merge branch 'dl/complete-cherry-pick-revert-skip'
[git/git.git] / kwset.c
CommitLineData
fca65d4b
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1/*
2 * This file has been copied from commit e7ac713d^ in the GNU grep git
3 * repository. A few small changes have been made to adapt the code to
4 * Git.
5 */
6
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7/* kwset.c - search for any of a set of keywords.
8 Copyright 1989, 1998, 2000, 2005 Free Software Foundation, Inc.
9
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2, or (at your option)
13 any later version.
14
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
19
20 You should have received a copy of the GNU General Public License
48425792 21 along with this program; if not, see <http://www.gnu.org/licenses/>. */
05f3dbba
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22
23/* Written August 1989 by Mike Haertel.
24 The author may be reached (Email) at the address mike@ai.mit.edu,
25 or (US mail) as Mike Haertel c/o Free Software Foundation. */
26
2fec81cb 27/* The algorithm implemented by these routines bears a startling resemblance
05f3dbba
FK
28 to one discovered by Beate Commentz-Walter, although it is not identical.
29 See "A String Matching Algorithm Fast on the Average," Technical Report,
30 IBM-Germany, Scientific Center Heidelberg, Tiergartenstrasse 15, D-6900
31 Heidelberg, Germany. See also Aho, A.V., and M. Corasick, "Efficient
32 String Matching: An Aid to Bibliographic Search," CACM June 1975,
33 Vol. 18, No. 6, which describes the failure function used below. */
34
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35#include "cache.h"
36
05f3dbba 37#include "kwset.h"
d190a087 38#include "compat/obstack.h"
05f3dbba 39
05f3dbba 40#define NCHAR (UCHAR_MAX + 1)
08e04506
JS
41/* adapter for `xmalloc()`, which takes `size_t`, not `long` */
42static void *obstack_chunk_alloc(long size)
43{
44 if (size < 0)
45 BUG("Cannot allocate a negative amount: %ld", size);
46 return xmalloc(size);
47}
05f3dbba
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48#define obstack_chunk_free free
49
50#define U(c) ((unsigned char) (c))
51
52/* Balanced tree of edges and labels leaving a given trie node. */
53struct tree
54{
55 struct tree *llink; /* Left link; MUST be first field. */
56 struct tree *rlink; /* Right link (to larger labels). */
57 struct trie *trie; /* Trie node pointed to by this edge. */
58 unsigned char label; /* Label on this edge. */
59 char balance; /* Difference in depths of subtrees. */
60};
61
62/* Node of a trie representing a set of reversed keywords. */
63struct trie
64{
65 unsigned int accepting; /* Word index of accepted word, or zero. */
66 struct tree *links; /* Tree of edges leaving this node. */
67 struct trie *parent; /* Parent of this node. */
68 struct trie *next; /* List of all trie nodes in level order. */
69 struct trie *fail; /* Aho-Corasick failure function. */
70 int depth; /* Depth of this node from the root. */
71 int shift; /* Shift function for search failures. */
749f763d 72 int maxshift; /* Max shift of self and descendants. */
05f3dbba
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73};
74
75/* Structure returned opaquely to the caller, containing everything. */
76struct kwset
77{
78 struct obstack obstack; /* Obstack for node allocation. */
79 int words; /* Number of words in the trie. */
80 struct trie *trie; /* The trie itself. */
81 int mind; /* Minimum depth of an accepting node. */
82 int maxd; /* Maximum depth of any node. */
83 unsigned char delta[NCHAR]; /* Delta table for rapid search. */
84 struct trie *next[NCHAR]; /* Table of children of the root. */
85 char *target; /* Target string if there's only one. */
86 int mind2; /* Used in Boyer-Moore search for one string. */
189c860c 87 unsigned char const *trans; /* Character translation table. */
05f3dbba
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88};
89
90/* Allocate and initialize a keyword set object, returning an opaque
91 pointer to it. Return NULL if memory is not available. */
92kwset_t
189c860c 93kwsalloc (unsigned char const *trans)
05f3dbba
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94{
95 struct kwset *kwset;
96
fca65d4b 97 kwset = (struct kwset *) xmalloc(sizeof (struct kwset));
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98
99 obstack_init(&kwset->obstack);
100 kwset->words = 0;
101 kwset->trie
102 = (struct trie *) obstack_alloc(&kwset->obstack, sizeof (struct trie));
103 if (!kwset->trie)
104 {
105 kwsfree((kwset_t) kwset);
106 return NULL;
107 }
108 kwset->trie->accepting = 0;
109 kwset->trie->links = NULL;
110 kwset->trie->parent = NULL;
111 kwset->trie->next = NULL;
112 kwset->trie->fail = NULL;
113 kwset->trie->depth = 0;
114 kwset->trie->shift = 0;
115 kwset->mind = INT_MAX;
116 kwset->maxd = -1;
117 kwset->target = NULL;
118 kwset->trans = trans;
119
120 return (kwset_t) kwset;
121}
122
123/* This upper bound is valid for CHAR_BIT >= 4 and
124 exact for CHAR_BIT in { 4..11, 13, 15, 17, 19 }. */
125#define DEPTH_SIZE (CHAR_BIT + CHAR_BIT/2)
126
127/* Add the given string to the contents of the keyword set. Return NULL
128 for success, an error message otherwise. */
129const char *
130kwsincr (kwset_t kws, char const *text, size_t len)
131{
132 struct kwset *kwset;
133 register struct trie *trie;
134 register unsigned char label;
135 register struct tree *link;
136 register int depth;
137 struct tree *links[DEPTH_SIZE];
138 enum { L, R } dirs[DEPTH_SIZE];
139 struct tree *t, *r, *l, *rl, *lr;
140
141 kwset = (struct kwset *) kws;
142 trie = kwset->trie;
143 text += len;
144
145 /* Descend the trie (built of reversed keywords) character-by-character,
146 installing new nodes when necessary. */
147 while (len--)
148 {
149 label = kwset->trans ? kwset->trans[U(*--text)] : *--text;
150
151 /* Descend the tree of outgoing links for this trie node,
152 looking for the current character and keeping track
153 of the path followed. */
154 link = trie->links;
155 links[0] = (struct tree *) &trie->links;
156 dirs[0] = L;
157 depth = 1;
158
159 while (link && label != link->label)
160 {
161 links[depth] = link;
162 if (label < link->label)
163 dirs[depth++] = L, link = link->llink;
164 else
165 dirs[depth++] = R, link = link->rlink;
166 }
167
168 /* The current character doesn't have an outgoing link at
169 this trie node, so build a new trie node and install
170 a link in the current trie node's tree. */
171 if (!link)
172 {
173 link = (struct tree *) obstack_alloc(&kwset->obstack,
174 sizeof (struct tree));
175 if (!link)
fca65d4b 176 return "memory exhausted";
05f3dbba
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177 link->llink = NULL;
178 link->rlink = NULL;
179 link->trie = (struct trie *) obstack_alloc(&kwset->obstack,
180 sizeof (struct trie));
181 if (!link->trie)
182 {
183 obstack_free(&kwset->obstack, link);
fca65d4b 184 return "memory exhausted";
05f3dbba
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185 }
186 link->trie->accepting = 0;
187 link->trie->links = NULL;
188 link->trie->parent = trie;
189 link->trie->next = NULL;
190 link->trie->fail = NULL;
191 link->trie->depth = trie->depth + 1;
192 link->trie->shift = 0;
193 link->label = label;
194 link->balance = 0;
195
196 /* Install the new tree node in its parent. */
197 if (dirs[--depth] == L)
198 links[depth]->llink = link;
199 else
200 links[depth]->rlink = link;
201
202 /* Back up the tree fixing the balance flags. */
203 while (depth && !links[depth]->balance)
204 {
205 if (dirs[depth] == L)
206 --links[depth]->balance;
207 else
208 ++links[depth]->balance;
209 --depth;
210 }
211
212 /* Rebalance the tree by pointer rotations if necessary. */
213 if (depth && ((dirs[depth] == L && --links[depth]->balance)
214 || (dirs[depth] == R && ++links[depth]->balance)))
215 {
216 switch (links[depth]->balance)
217 {
218 case (char) -2:
219 switch (dirs[depth + 1])
220 {
221 case L:
222 r = links[depth], t = r->llink, rl = t->rlink;
223 t->rlink = r, r->llink = rl;
224 t->balance = r->balance = 0;
225 break;
226 case R:
227 r = links[depth], l = r->llink, t = l->rlink;
228 rl = t->rlink, lr = t->llink;
229 t->llink = l, l->rlink = lr, t->rlink = r, r->llink = rl;
230 l->balance = t->balance != 1 ? 0 : -1;
231 r->balance = t->balance != (char) -1 ? 0 : 1;
232 t->balance = 0;
233 break;
234 default:
235 abort ();
236 }
237 break;
238 case 2:
239 switch (dirs[depth + 1])
240 {
241 case R:
242 l = links[depth], t = l->rlink, lr = t->llink;
243 t->llink = l, l->rlink = lr;
244 t->balance = l->balance = 0;
245 break;
246 case L:
247 l = links[depth], r = l->rlink, t = r->llink;
248 lr = t->llink, rl = t->rlink;
249 t->llink = l, l->rlink = lr, t->rlink = r, r->llink = rl;
250 l->balance = t->balance != 1 ? 0 : -1;
251 r->balance = t->balance != (char) -1 ? 0 : 1;
252 t->balance = 0;
253 break;
254 default:
255 abort ();
256 }
257 break;
258 default:
259 abort ();
260 }
261
262 if (dirs[depth - 1] == L)
263 links[depth - 1]->llink = t;
264 else
265 links[depth - 1]->rlink = t;
266 }
267 }
268
269 trie = link->trie;
270 }
271
272 /* Mark the node we finally reached as accepting, encoding the
273 index number of this word in the keyword set so far. */
274 if (!trie->accepting)
275 trie->accepting = 1 + 2 * kwset->words;
276 ++kwset->words;
277
278 /* Keep track of the longest and shortest string of the keyword set. */
279 if (trie->depth < kwset->mind)
280 kwset->mind = trie->depth;
281 if (trie->depth > kwset->maxd)
282 kwset->maxd = trie->depth;
283
284 return NULL;
285}
286
287/* Enqueue the trie nodes referenced from the given tree in the
288 given queue. */
289static void
290enqueue (struct tree *tree, struct trie **last)
291{
292 if (!tree)
293 return;
294 enqueue(tree->llink, last);
295 enqueue(tree->rlink, last);
296 (*last) = (*last)->next = tree->trie;
297}
298
299/* Compute the Aho-Corasick failure function for the trie nodes referenced
300 from the given tree, given the failure function for their parent as
301 well as a last resort failure node. */
302static void
303treefails (register struct tree const *tree, struct trie const *fail,
304 struct trie *recourse)
305{
306 register struct tree *link;
307
308 if (!tree)
309 return;
310
311 treefails(tree->llink, fail, recourse);
312 treefails(tree->rlink, fail, recourse);
313
314 /* Find, in the chain of fails going back to the root, the first
749f763d 315 node that has a descendant on the current label. */
05f3dbba
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316 while (fail)
317 {
318 link = fail->links;
319 while (link && tree->label != link->label)
320 if (tree->label < link->label)
321 link = link->llink;
322 else
323 link = link->rlink;
324 if (link)
325 {
326 tree->trie->fail = link->trie;
327 return;
328 }
329 fail = fail->fail;
330 }
331
332 tree->trie->fail = recourse;
333}
334
335/* Set delta entries for the links of the given tree such that
336 the preexisting delta value is larger than the current depth. */
337static void
338treedelta (register struct tree const *tree,
339 register unsigned int depth,
340 unsigned char delta[])
341{
342 if (!tree)
343 return;
344 treedelta(tree->llink, depth, delta);
345 treedelta(tree->rlink, depth, delta);
346 if (depth < delta[tree->label])
347 delta[tree->label] = depth;
348}
349
350/* Return true if A has every label in B. */
351static int
352hasevery (register struct tree const *a, register struct tree const *b)
353{
354 if (!b)
355 return 1;
356 if (!hasevery(a, b->llink))
357 return 0;
358 if (!hasevery(a, b->rlink))
359 return 0;
360 while (a && b->label != a->label)
361 if (b->label < a->label)
362 a = a->llink;
363 else
364 a = a->rlink;
365 return !!a;
366}
367
368/* Compute a vector, indexed by character code, of the trie nodes
369 referenced from the given tree. */
370static void
371treenext (struct tree const *tree, struct trie *next[])
372{
373 if (!tree)
374 return;
375 treenext(tree->llink, next);
376 treenext(tree->rlink, next);
377 next[tree->label] = tree->trie;
378}
379
380/* Compute the shift for each trie node, as well as the delta
381 table and next cache for the given keyword set. */
382const char *
383kwsprep (kwset_t kws)
384{
385 register struct kwset *kwset;
386 register int i;
387 register struct trie *curr;
189c860c 388 register unsigned char const *trans;
05f3dbba
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389 unsigned char delta[NCHAR];
390
391 kwset = (struct kwset *) kws;
392
393 /* Initial values for the delta table; will be changed later. The
394 delta entry for a given character is the smallest depth of any
395 node at which an outgoing edge is labeled by that character. */
396 memset(delta, kwset->mind < UCHAR_MAX ? kwset->mind : UCHAR_MAX, NCHAR);
397
398 /* Check if we can use the simple boyer-moore algorithm, instead
399 of the hairy commentz-walter algorithm. */
400 if (kwset->words == 1 && kwset->trans == NULL)
401 {
402 char c;
403
404 /* Looking for just one string. Extract it from the trie. */
405 kwset->target = obstack_alloc(&kwset->obstack, kwset->mind);
406 if (!kwset->target)
fca65d4b 407 return "memory exhausted";
05f3dbba
FK
408 for (i = kwset->mind - 1, curr = kwset->trie; i >= 0; --i)
409 {
410 kwset->target[i] = curr->links->label;
411 curr = curr->links->trie;
412 }
413 /* Build the Boyer Moore delta. Boy that's easy compared to CW. */
414 for (i = 0; i < kwset->mind; ++i)
415 delta[U(kwset->target[i])] = kwset->mind - (i + 1);
416 /* Find the minimal delta2 shift that we might make after
417 a backwards match has failed. */
418 c = kwset->target[kwset->mind - 1];
419 for (i = kwset->mind - 2; i >= 0; --i)
420 if (kwset->target[i] == c)
421 break;
422 kwset->mind2 = kwset->mind - (i + 1);
423 }
424 else
425 {
426 register struct trie *fail;
427 struct trie *last, *next[NCHAR];
428
429 /* Traverse the nodes of the trie in level order, simultaneously
430 computing the delta table, failure function, and shift function. */
431 for (curr = last = kwset->trie; curr; curr = curr->next)
432 {
749f763d 433 /* Enqueue the immediate descendants in the level order queue. */
05f3dbba
FK
434 enqueue(curr->links, &last);
435
436 curr->shift = kwset->mind;
437 curr->maxshift = kwset->mind;
438
749f763d 439 /* Update the delta table for the descendants of this node. */
05f3dbba
FK
440 treedelta(curr->links, curr->depth, delta);
441
2fec81cb 442 /* Compute the failure function for the descendants of this node. */
05f3dbba
FK
443 treefails(curr->links, curr->fail, kwset->trie);
444
445 /* Update the shifts at each node in the current node's chain
446 of fails back to the root. */
447 for (fail = curr->fail; fail; fail = fail->fail)
448 {
449 /* If the current node has some outgoing edge that the fail
450 doesn't, then the shift at the fail should be no larger
451 than the difference of their depths. */
452 if (!hasevery(fail->links, curr->links))
453 if (curr->depth - fail->depth < fail->shift)
454 fail->shift = curr->depth - fail->depth;
455
456 /* If the current node is accepting then the shift at the
749f763d 457 fail and its descendants should be no larger than the
05f3dbba
FK
458 difference of their depths. */
459 if (curr->accepting && fail->maxshift > curr->depth - fail->depth)
460 fail->maxshift = curr->depth - fail->depth;
461 }
462 }
463
464 /* Traverse the trie in level order again, fixing up all nodes whose
465 shift exceeds their inherited maxshift. */
466 for (curr = kwset->trie->next; curr; curr = curr->next)
467 {
468 if (curr->maxshift > curr->parent->maxshift)
469 curr->maxshift = curr->parent->maxshift;
470 if (curr->shift > curr->maxshift)
471 curr->shift = curr->maxshift;
472 }
473
474 /* Create a vector, indexed by character code, of the outgoing links
475 from the root node. */
476 for (i = 0; i < NCHAR; ++i)
477 next[i] = NULL;
478 treenext(kwset->trie->links, next);
479
480 if ((trans = kwset->trans) != NULL)
481 for (i = 0; i < NCHAR; ++i)
482 kwset->next[i] = next[U(trans[i])];
483 else
921d49be 484 COPY_ARRAY(kwset->next, next, NCHAR);
05f3dbba
FK
485 }
486
487 /* Fix things up for any translation table. */
488 if ((trans = kwset->trans) != NULL)
489 for (i = 0; i < NCHAR; ++i)
490 kwset->delta[i] = delta[U(trans[i])];
491 else
492 memcpy(kwset->delta, delta, NCHAR);
493
494 return NULL;
495}
496
497/* Fast boyer-moore search. */
498static size_t
499bmexec (kwset_t kws, char const *text, size_t size)
500{
501 struct kwset const *kwset;
502 register unsigned char const *d1;
503 register char const *ep, *sp, *tp;
504 register int d, gc, i, len, md2;
505
506 kwset = (struct kwset const *) kws;
507 len = kwset->mind;
508
509 if (len == 0)
510 return 0;
511 if (len > size)
512 return -1;
513 if (len == 1)
514 {
515 tp = memchr (text, kwset->target[0], size);
516 return tp ? tp - text : -1;
517 }
518
519 d1 = kwset->delta;
520 sp = kwset->target + len;
521 gc = U(sp[-2]);
522 md2 = kwset->mind2;
523 tp = text + len;
524
525 /* Significance of 12: 1 (initial offset) + 10 (skip loop) + 1 (md2). */
526 if (size > 12 * len)
527 /* 11 is not a bug, the initial offset happens only once. */
528 for (ep = text + size - 11 * len;;)
529 {
530 while (tp <= ep)
531 {
532 d = d1[U(tp[-1])], tp += d;
533 d = d1[U(tp[-1])], tp += d;
534 if (d == 0)
535 goto found;
536 d = d1[U(tp[-1])], tp += d;
537 d = d1[U(tp[-1])], tp += d;
538 d = d1[U(tp[-1])], tp += d;
539 if (d == 0)
540 goto found;
541 d = d1[U(tp[-1])], tp += d;
542 d = d1[U(tp[-1])], tp += d;
543 d = d1[U(tp[-1])], tp += d;
544 if (d == 0)
545 goto found;
546 d = d1[U(tp[-1])], tp += d;
547 d = d1[U(tp[-1])], tp += d;
548 }
549 break;
550 found:
551 if (U(tp[-2]) == gc)
552 {
553 for (i = 3; i <= len && U(tp[-i]) == U(sp[-i]); ++i)
554 ;
555 if (i > len)
556 return tp - len - text;
557 }
558 tp += md2;
559 }
560
561 /* Now we have only a few characters left to search. We
562 carefully avoid ever producing an out-of-bounds pointer. */
563 ep = text + size;
564 d = d1[U(tp[-1])];
565 while (d <= ep - tp)
566 {
567 d = d1[U((tp += d)[-1])];
568 if (d != 0)
569 continue;
570 if (U(tp[-2]) == gc)
571 {
572 for (i = 3; i <= len && U(tp[-i]) == U(sp[-i]); ++i)
573 ;
574 if (i > len)
575 return tp - len - text;
576 }
577 d = md2;
578 }
579
580 return -1;
581}
582
583/* Hairy multiple string search. */
584static size_t
585cwexec (kwset_t kws, char const *text, size_t len, struct kwsmatch *kwsmatch)
586{
587 struct kwset const *kwset;
588 struct trie * const *next;
589 struct trie const *trie;
590 struct trie const *accept;
591 char const *beg, *lim, *mch, *lmch;
592 register unsigned char c;
593 register unsigned char const *delta;
594 register int d;
595 register char const *end, *qlim;
596 register struct tree const *tree;
189c860c 597 register unsigned char const *trans;
05f3dbba 598
05f3dbba 599 accept = NULL;
05f3dbba
FK
600
601 /* Initialize register copies and look for easy ways out. */
602 kwset = (struct kwset *) kws;
603 if (len < kwset->mind)
604 return -1;
605 next = kwset->next;
606 delta = kwset->delta;
607 trans = kwset->trans;
608 lim = text + len;
609 end = text;
610 if ((d = kwset->mind) != 0)
611 mch = NULL;
612 else
613 {
614 mch = text, accept = kwset->trie;
615 goto match;
616 }
617
618 if (len >= 4 * kwset->mind)
619 qlim = lim - 4 * kwset->mind;
620 else
621 qlim = NULL;
622
623 while (lim - end >= d)
624 {
625 if (qlim && end <= qlim)
626 {
627 end += d - 1;
628 while ((d = delta[c = *end]) && end < qlim)
629 {
630 end += d;
631 end += delta[U(*end)];
632 end += delta[U(*end)];
633 }
634 ++end;
635 }
636 else
637 d = delta[c = (end += d)[-1]];
638 if (d)
639 continue;
640 beg = end - 1;
641 trie = next[c];
642 if (trie->accepting)
643 {
644 mch = beg;
645 accept = trie;
646 }
647 d = trie->shift;
648 while (beg > text)
649 {
650 c = trans ? trans[U(*--beg)] : *--beg;
651 tree = trie->links;
652 while (tree && c != tree->label)
653 if (c < tree->label)
654 tree = tree->llink;
655 else
656 tree = tree->rlink;
657 if (tree)
658 {
659 trie = tree->trie;
660 if (trie->accepting)
661 {
662 mch = beg;
663 accept = trie;
664 }
665 }
666 else
667 break;
668 d = trie->shift;
669 }
670 if (mch)
671 goto match;
672 }
673 return -1;
674
675 match:
676 /* Given a known match, find the longest possible match anchored
677 at or before its starting point. This is nearly a verbatim
678 copy of the preceding main search loops. */
679 if (lim - mch > kwset->maxd)
680 lim = mch + kwset->maxd;
a946ef55 681 lmch = NULL;
05f3dbba
FK
682 d = 1;
683 while (lim - end >= d)
684 {
685 if ((d = delta[c = (end += d)[-1]]) != 0)
686 continue;
687 beg = end - 1;
688 if (!(trie = next[c]))
689 {
690 d = 1;
691 continue;
692 }
693 if (trie->accepting && beg <= mch)
694 {
695 lmch = beg;
696 accept = trie;
697 }
698 d = trie->shift;
699 while (beg > text)
700 {
701 c = trans ? trans[U(*--beg)] : *--beg;
702 tree = trie->links;
703 while (tree && c != tree->label)
704 if (c < tree->label)
705 tree = tree->llink;
706 else
707 tree = tree->rlink;
708 if (tree)
709 {
710 trie = tree->trie;
711 if (trie->accepting && beg <= mch)
712 {
713 lmch = beg;
714 accept = trie;
715 }
716 }
717 else
718 break;
719 d = trie->shift;
720 }
721 if (lmch)
722 {
723 mch = lmch;
724 goto match;
725 }
726 if (!d)
727 d = 1;
728 }
729
730 if (kwsmatch)
731 {
732 kwsmatch->index = accept->accepting / 2;
733 kwsmatch->offset[0] = mch - text;
734 kwsmatch->size[0] = accept->depth;
735 }
736 return mch - text;
737}
738
739/* Search through the given text for a match of any member of the
740 given keyword set. Return a pointer to the first character of
741 the matching substring, or NULL if no match is found. If FOUNDLEN
742 is non-NULL store in the referenced location the length of the
743 matching substring. Similarly, if FOUNDIDX is non-NULL, store
744 in the referenced location the index number of the particular
745 keyword matched. */
746size_t
747kwsexec (kwset_t kws, char const *text, size_t size,
748 struct kwsmatch *kwsmatch)
749{
750 struct kwset const *kwset = (struct kwset *) kws;
751 if (kwset->words == 1 && kwset->trans == NULL)
752 {
753 size_t ret = bmexec (kws, text, size);
754 if (kwsmatch != NULL && ret != (size_t) -1)
755 {
756 kwsmatch->index = 0;
757 kwsmatch->offset[0] = ret;
758 kwsmatch->size[0] = kwset->mind;
759 }
760 return ret;
761 }
762 else
763 return cwexec(kws, text, size, kwsmatch);
764}
765
766/* Free the components of the given keyword set. */
767void
768kwsfree (kwset_t kws)
769{
770 struct kwset *kwset;
771
772 kwset = (struct kwset *) kws;
773 obstack_free(&kwset->obstack, NULL);
774 free(kws);
775}