70322ae3 |
1 | /* |
2 | * trie.c: implementation of trie.h. |
3 | */ |
4 | |
5 | #include <assert.h> |
6 | #include <stdio.h> |
7 | #include <string.h> |
8 | #include <stdlib.h> |
9 | #include <errno.h> |
10 | |
11 | #include <sys/types.h> |
12 | #include <unistd.h> |
13 | |
353bc75d |
14 | #include "agedu.h" |
995db599 |
15 | #include "alloc.h" |
70322ae3 |
16 | #include "trie.h" |
17 | |
18 | #define alignof(typ) ( offsetof(struct { char c; typ t; }, t) ) |
19 | |
20 | /* |
21 | * Compare functions for pathnames. Returns the relative order of |
22 | * the names, like strcmp; also passes back the offset of the |
23 | * first differing character if desired. |
24 | */ |
25 | static int trieccmp(unsigned char a, unsigned char b) |
26 | { |
373a02e5 |
27 | a = (a == '\0' ? '\0' : a == pathsep ? '\1' : a+1); |
28 | b = (b == '\0' ? '\0' : b == pathsep ? '\1' : b+1); |
29 | return (int)a - (int)b; |
70322ae3 |
30 | } |
31 | |
32 | static int triencmp(const char *a, size_t alen, |
33 | const char *b, size_t blen, int *offset) |
34 | { |
35 | int off = 0; |
36 | while (off < alen && off < blen && a[off] == b[off]) |
37 | off++; |
38 | if (offset) |
39 | *offset = off; |
40 | if (off == alen || off == blen) return (off == blen) - (off == alen); |
41 | return trieccmp(a[off], b[off]); |
42 | } |
43 | |
44 | static int triecmp(const char *a, const char *b, int *offset) |
45 | { |
46 | return triencmp(a, strlen(a), b, strlen(b), offset); |
47 | } |
48 | |
49 | /* ---------------------------------------------------------------------- |
50 | * Trie node structures. |
51 | * |
52 | * The trie format stored in the file consists of three distinct |
53 | * node types, each with a distinguishing type field at the start. |
54 | * |
55 | * TRIE_LEAF is a leaf node; it contains an actual trie_file |
56 | * structure, and indicates that when you're searching down the |
57 | * trie with a string, you should now expect to encounter |
58 | * end-of-string. |
59 | * |
60 | * TRIE_SWITCH indicates that the set of strings in the trie |
61 | * include strings with more than one distinct character after the |
62 | * prefix leading up to this point. Hence, it stores multiple |
63 | * subnode pointers and a different single character for each one. |
64 | * |
65 | * TRIE_STRING indicates that at this point everything in the trie |
66 | * has the same next few characters; it stores a single mandatory |
67 | * string fragment and exactly one subnode pointer. |
68 | */ |
69 | enum { |
70 | TRIE_LEAF = 0x7fffe000, |
71 | TRIE_SWITCH, |
72 | TRIE_STRING |
73 | }; |
74 | |
75 | struct trie_common { |
76 | int type; |
77 | }; |
78 | |
79 | struct trie_switchentry { |
80 | off_t subnode; |
81 | int subcount; |
82 | }; |
83 | |
84 | struct trie_leaf { |
85 | struct trie_common c; |
86 | struct trie_file file; |
87 | }; |
88 | |
89 | struct trie_switch { |
90 | struct trie_common c; |
91 | /* |
92 | * sw[0] to sw[len-1] give the subnode pointers and element |
93 | * counts. At &sw[len] is stored len single bytes which are |
94 | * the characters corresponding to each subnode. |
95 | */ |
96 | int len; |
97 | struct trie_switchentry sw[]; |
98 | }; |
99 | |
100 | struct trie_string { |
101 | struct trie_common c; |
102 | int stringlen; |
103 | off_t subnode; |
104 | char string[]; |
105 | }; |
106 | |
107 | struct trie_header { |
108 | unsigned long magic; |
109 | off_t root, indexroot; |
110 | int count; |
111 | size_t maxpathlen; |
269fa2d1 |
112 | int pathsep; |
70322ae3 |
113 | }; |
114 | |
115 | /* Union only used for computing alignment */ |
116 | union trie_node { |
117 | struct trie_leaf leaf; |
118 | struct { /* fake trie_switch with indeterminate array length filled in */ |
119 | struct trie_common c; |
120 | int len; |
121 | struct trie_switchentry sw[1]; |
122 | } sw; |
123 | struct { /* fake trie_string with indeterminate array length filled in */ |
124 | struct trie_common c; |
125 | int stringlen; |
126 | off_t subnode; |
127 | char string[1]; |
128 | } str; |
129 | }; |
130 | #define TRIE_MAGIC 0x75646761UL |
131 | #define TRIE_ALIGN alignof(union trie_node) |
132 | |
133 | /* ---------------------------------------------------------------------- |
134 | * Trie-building functions. |
135 | */ |
136 | |
137 | struct tbswitch { |
138 | int len; |
139 | char c[256]; |
140 | off_t off[256]; |
141 | int count[256]; |
142 | }; |
143 | |
144 | struct triebuild { |
145 | int fd; |
146 | off_t offset; |
147 | char *lastpath; |
148 | int lastlen, lastsize; |
149 | off_t lastoff; |
150 | struct tbswitch *switches; |
151 | int switchsize; |
152 | size_t maxpathlen; |
153 | }; |
154 | |
155 | static void tb_seek(triebuild *tb, off_t off) |
156 | { |
157 | tb->offset = off; |
158 | if (lseek(tb->fd, off, SEEK_SET) < 0) { |
bf53e756 |
159 | fprintf(stderr, PNAME ": lseek: %s\n", strerror(errno)); |
70322ae3 |
160 | exit(1); |
161 | } |
162 | } |
163 | |
164 | static void tb_write(triebuild *tb, const void *buf, size_t len) |
165 | { |
166 | tb->offset += len; |
167 | while (len > 0) { |
168 | int ret = write(tb->fd, buf, len); |
169 | if (ret < 0) { |
bf53e756 |
170 | fprintf(stderr, PNAME ": write: %s\n", strerror(errno)); |
70322ae3 |
171 | exit(1); |
172 | } |
173 | len -= ret; |
174 | buf = (const void *)((const char *)buf + ret); |
175 | } |
176 | } |
177 | |
178 | static char trie_align_zeroes[TRIE_ALIGN]; |
179 | |
180 | static void tb_align(triebuild *tb) |
181 | { |
182 | int off = (TRIE_ALIGN - ((tb)->offset % TRIE_ALIGN)) % TRIE_ALIGN; |
183 | tb_write(tb, trie_align_zeroes, off); |
184 | } |
185 | |
186 | triebuild *triebuild_new(int fd) |
187 | { |
188 | triebuild *tb = snew(triebuild); |
189 | struct trie_header th; |
190 | |
191 | tb->fd = fd; |
192 | tb->lastpath = NULL; |
193 | tb->lastlen = tb->lastsize = 0; |
194 | tb->lastoff = 0; |
195 | tb->switches = NULL; |
196 | tb->switchsize = 0; |
197 | tb->maxpathlen = 0; |
198 | |
199 | th.magic = TRIE_MAGIC; |
200 | th.root = th.count = 0; |
201 | th.indexroot = 0; |
202 | th.maxpathlen = 0; |
269fa2d1 |
203 | th.pathsep = (unsigned char)pathsep; |
70322ae3 |
204 | |
205 | tb_seek(tb, 0); |
206 | tb_write(tb, &th, sizeof(th)); |
207 | |
208 | return tb; |
209 | } |
210 | |
211 | static off_t triebuild_unwind(triebuild *tb, int targetdepth, int *outcount) |
212 | { |
213 | off_t offset; |
214 | int count, depth; |
215 | |
216 | if (tb->lastoff == 0) { |
217 | *outcount = 0; |
218 | return 0; |
219 | } |
220 | |
221 | offset = tb->lastoff; |
222 | count = 1; |
223 | depth = tb->lastlen + 1; |
224 | |
225 | assert(depth >= targetdepth); |
226 | |
227 | while (depth > targetdepth) { |
228 | int odepth = depth; |
229 | while (depth > targetdepth && |
230 | (depth-1 > tb->switchsize || tb->switches[depth-1].len == 0)) |
231 | depth--; |
232 | if (odepth > depth) { |
233 | /* |
234 | * Write out a string node. |
235 | */ |
236 | size_t nodesize = sizeof(struct trie_string) + odepth - depth; |
237 | struct trie_string *st = (struct trie_string *)smalloc(nodesize); |
238 | st->c.type = TRIE_STRING; |
239 | st->stringlen = odepth - depth; |
240 | st->subnode = offset; |
241 | memcpy(st->string, tb->lastpath + depth, odepth - depth); |
242 | tb_align(tb); |
243 | offset = tb->offset; |
244 | tb_write(tb, st, nodesize); |
245 | sfree(st); |
246 | } |
247 | |
248 | assert(depth >= targetdepth); |
249 | if (depth <= targetdepth) |
250 | break; |
251 | |
252 | /* |
253 | * Now we expect to be sitting just below a switch node. |
254 | * Add our final entry to it and write it out. |
255 | */ |
256 | depth--; |
257 | { |
258 | struct trie_switch *sw; |
259 | char *chars; |
260 | size_t nodesize; |
261 | int swlen = tb->switches[depth].len; |
262 | int i; |
263 | |
264 | assert(swlen > 0); |
265 | |
266 | tb->switches[depth].c[swlen] = tb->lastpath[depth]; |
267 | tb->switches[depth].off[swlen] = offset; |
268 | tb->switches[depth].count[swlen] = count; |
269 | swlen++; |
270 | |
271 | nodesize = sizeof(struct trie_switch) + |
272 | swlen * sizeof(struct trie_switchentry) + swlen; |
273 | sw = (struct trie_switch *)smalloc(nodesize); |
274 | chars = (char *)&sw->sw[swlen]; |
275 | |
276 | sw->c.type = TRIE_SWITCH; |
277 | sw->len = swlen; |
278 | count = 0; |
279 | for (i = 0; i < swlen; i++) { |
280 | sw->sw[i].subnode = tb->switches[depth].off[i]; |
281 | sw->sw[i].subcount = tb->switches[depth].count[i]; |
282 | chars[i] = tb->switches[depth].c[i]; |
283 | |
284 | count += tb->switches[depth].count[i]; |
285 | } |
286 | |
287 | tb_align(tb); |
288 | offset = tb->offset; |
289 | tb_write(tb, sw, nodesize); |
290 | sfree(sw); |
291 | |
292 | tb->switches[depth].len = 0; /* clear this node */ |
293 | } |
294 | } |
295 | |
296 | *outcount = count; |
297 | return offset; |
298 | } |
299 | |
300 | void triebuild_add(triebuild *tb, const char *pathname, |
301 | const struct trie_file *file) |
302 | { |
303 | int pathlen = strlen(pathname); |
304 | int depth; |
305 | |
306 | if (tb->maxpathlen < pathlen+1) |
307 | tb->maxpathlen = pathlen+1; |
308 | |
309 | if (tb->lastpath) { |
310 | off_t offset; |
311 | int count; |
312 | |
313 | /* |
314 | * Find the first differing character between this pathname |
315 | * and the previous one. |
316 | */ |
317 | int ret = triecmp(tb->lastpath, pathname, &depth); |
318 | assert(ret < 0); |
319 | |
320 | /* |
321 | * Finalise all nodes above this depth. |
322 | */ |
323 | offset = triebuild_unwind(tb, depth+1, &count); |
324 | |
325 | /* |
326 | * Add the final node we just acquired to the switch node |
327 | * at our chosen depth, creating it if it isn't already |
328 | * there. |
329 | */ |
330 | if (tb->switchsize <= depth) { |
331 | int oldsize = tb->switchsize; |
332 | tb->switchsize = depth * 3 / 2 + 64; |
333 | tb->switches = sresize(tb->switches, tb->switchsize, |
334 | struct tbswitch); |
335 | while (oldsize < tb->switchsize) |
336 | tb->switches[oldsize++].len = 0; |
337 | } |
338 | |
339 | tb->switches[depth].c[tb->switches[depth].len] = tb->lastpath[depth]; |
340 | tb->switches[depth].off[tb->switches[depth].len] = offset; |
341 | tb->switches[depth].count[tb->switches[depth].len] = count; |
342 | tb->switches[depth].len++; |
343 | } |
344 | |
345 | /* |
346 | * Write out a leaf node for the new file, and remember its |
347 | * file offset. |
348 | */ |
349 | { |
350 | struct trie_leaf leaf; |
351 | |
352 | leaf.c.type = TRIE_LEAF; |
353 | leaf.file = *file; /* structure copy */ |
354 | |
355 | tb_align(tb); |
356 | tb->lastoff = tb->offset; |
357 | tb_write(tb, &leaf, sizeof(leaf)); |
358 | } |
359 | |
360 | /* |
361 | * Store this pathname for comparison with the next one. |
362 | */ |
363 | if (tb->lastsize < pathlen+1) { |
364 | tb->lastsize = pathlen * 3 / 2 + 64; |
365 | tb->lastpath = sresize(tb->lastpath, tb->lastsize, char); |
366 | } |
367 | strcpy(tb->lastpath, pathname); |
368 | tb->lastlen = pathlen; |
369 | } |
370 | |
371 | int triebuild_finish(triebuild *tb) |
372 | { |
373 | struct trie_header th; |
374 | |
375 | th.magic = TRIE_MAGIC; |
376 | th.root = triebuild_unwind(tb, 0, &th.count); |
377 | th.indexroot = 0; |
378 | th.maxpathlen = tb->maxpathlen; |
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379 | th.pathsep = (unsigned char)pathsep; |
70322ae3 |
380 | |
381 | tb_seek(tb, 0); |
382 | tb_write(tb, &th, sizeof(th)); |
383 | |
384 | return th.count; |
385 | } |
386 | |
387 | void triebuild_free(triebuild *tb) |
388 | { |
389 | sfree(tb->switches); |
390 | sfree(tb->lastpath); |
391 | sfree(tb); |
392 | } |
393 | |
394 | /* ---------------------------------------------------------------------- |
05b0f827 |
395 | * Memory-mapped trie modification. |
396 | */ |
397 | |
398 | #define MNODE(t, off, type) \ |
399 | ((struct type *)((char *)(t) + (off))) |
400 | |
401 | static unsigned long long fake_atime_recurse(void *t, struct trie_common *node, |
402 | int last_seen_pathsep) |
403 | { |
404 | while (node->type == TRIE_STRING) { |
405 | struct trie_string *st = (struct trie_string *)node; |
406 | last_seen_pathsep = (st->string[st->stringlen-1] == pathsep); |
407 | node = MNODE(t, st->subnode, trie_common); |
408 | } |
409 | |
410 | if (node->type == TRIE_LEAF) { |
411 | struct trie_leaf *leaf = (struct trie_leaf *)node; |
412 | return leaf->file.atime; |
413 | } else if (assert(node->type == TRIE_SWITCH), 1) { |
414 | struct trie_switch *sw = (struct trie_switch *)node; |
415 | const char *chars = (const char *)&sw->sw[sw->len]; |
416 | unsigned long long max = 0, subdir, ret; |
417 | int i; |
418 | int slashindex = -1, bareindex = -1; |
419 | |
420 | /* |
421 | * First, process all the children of this node whose |
422 | * switch characters are not \0 or pathsep. We do this in |
423 | * reverse order so as to maintain best cache locality |
424 | * (tracking generally backwards through the file), though |
425 | * it doesn't matter semantically. |
426 | * |
427 | * For each of these children, we're just recursing into |
428 | * it to do any fixups required below it, and amalgamating |
429 | * the max atimes we get back. |
430 | */ |
431 | for (i = sw->len; i-- > 0 ;) { |
432 | if (chars[i] == '\0') { |
433 | bareindex = i; |
434 | } else if (chars[i] == pathsep) { |
435 | slashindex = i; |
436 | } else { |
437 | ret = fake_atime_recurse(t, MNODE(t, sw->sw[i].subnode, |
438 | trie_common), 0); |
439 | if (max < ret) |
440 | max = ret; |
441 | } |
442 | } |
443 | |
444 | /* |
445 | * Now we have at most two child nodes left to deal with: |
446 | * one with a slash (or general pathsep) and one with \0. |
447 | * |
448 | * If there's a slash node and a bare node, then the slash |
449 | * node contains precisely everything inside the directory |
450 | * described by the bare node; so we must retrieve the max |
451 | * atime for the slash node and use it to fix up the bare |
452 | * node. |
453 | * |
454 | * If there's only a bare node but the pathname leading up |
455 | * to this point ends in a slash, then _all_ of the child |
456 | * nodes of this node contain stuff inside the directory |
457 | * described by the bare node; so we use the whole of the |
458 | * maximum value we've computed so far to update the bare |
459 | * node. |
460 | */ |
461 | if (slashindex >= 0) { |
462 | ret = fake_atime_recurse(t, MNODE(t, sw->sw[slashindex].subnode, |
463 | trie_common), 1); |
464 | if (max < ret) |
465 | max = ret; |
466 | |
467 | subdir = ret; |
468 | } else if (last_seen_pathsep) { |
469 | subdir = max; |
470 | } else { |
471 | /* Don't update the bare subnode at all. */ |
472 | subdir = 0; |
473 | } |
474 | |
475 | if (bareindex >= 0) { |
476 | struct trie_leaf *leaf; |
477 | |
478 | leaf = MNODE(t, sw->sw[bareindex].subnode, trie_leaf); |
479 | |
480 | if (leaf && leaf->c.type == TRIE_LEAF) { |
481 | if (leaf->file.atime < subdir) |
482 | leaf->file.atime = subdir; |
483 | ret = leaf->file.atime; |
484 | } else { |
485 | /* Shouldn't really happen, but be cautious anyway */ |
486 | ret = fake_atime_recurse(t, &leaf->c, 0); |
487 | } |
488 | |
489 | if (max < ret) |
490 | max = ret; |
491 | } |
492 | |
493 | return max; |
494 | } |
495 | } |
496 | |
497 | void trie_fake_dir_atimes(void *t) |
498 | { |
499 | struct trie_header *hdr = MNODE(t, 0, trie_header); |
500 | struct trie_common *node = MNODE(t, hdr->root, trie_common); |
501 | |
502 | fake_atime_recurse(t, node, 1); |
503 | } |
504 | |
505 | /* ---------------------------------------------------------------------- |
70322ae3 |
506 | * Querying functions. |
507 | */ |
508 | |
509 | #define NODE(t, off, type) \ |
510 | ((const struct type *)((const char *)(t) + (off))) |
511 | |
512 | size_t trie_maxpathlen(const void *t) |
513 | { |
514 | const struct trie_header *hdr = NODE(t, 0, trie_header); |
515 | return hdr->maxpathlen; |
516 | } |
517 | |
518 | unsigned long trie_before(const void *t, const char *pathname) |
519 | { |
520 | const struct trie_header *hdr = NODE(t, 0, trie_header); |
521 | int ret = 0, lastcount = hdr->count; |
522 | int len = 1 + strlen(pathname), depth = 0; |
523 | off_t off = hdr->root; |
524 | |
525 | while (1) { |
526 | const struct trie_common *node = NODE(t, off, trie_common); |
527 | if (node->type == TRIE_LEAF) { |
528 | if (depth < len) |
529 | ret += lastcount; /* _shouldn't_ happen, but in principle */ |
530 | return ret; |
531 | } else if (node->type == TRIE_STRING) { |
532 | const struct trie_string *st = NODE(t, off, trie_string); |
533 | |
534 | int offset; |
535 | int cmp = triencmp(st->string, st->stringlen, |
536 | pathname + depth, len-depth, &offset); |
537 | |
538 | if (offset < st->stringlen) { |
539 | if (cmp < 0) |
540 | ret += lastcount; |
541 | return ret; |
542 | } |
543 | |
544 | depth += st->stringlen; |
545 | off = st->subnode; |
546 | } else if (node->type == TRIE_SWITCH) { |
547 | const struct trie_switch *sw = NODE(t, off, trie_switch); |
548 | const char *chars = (const char *)&sw->sw[sw->len]; |
549 | int i; |
550 | |
551 | for (i = 0; i < sw->len; i++) { |
552 | int c = chars[i]; |
553 | int cmp = trieccmp(pathname[depth], c); |
554 | if (cmp > 0) |
555 | ret += sw->sw[i].subcount; |
556 | else if (cmp < 0) |
557 | return ret; |
558 | else { |
559 | off = sw->sw[i].subnode; |
560 | lastcount = sw->sw[i].subcount; |
561 | depth++; |
562 | break; |
563 | } |
564 | } |
565 | if (i == sw->len) |
566 | return ret; |
567 | } |
568 | } |
569 | } |
570 | |
571 | void trie_getpath(const void *t, unsigned long n, char *buf) |
572 | { |
573 | const struct trie_header *hdr = NODE(t, 0, trie_header); |
574 | int depth = 0; |
575 | off_t off = hdr->root; |
576 | |
577 | while (1) { |
578 | const struct trie_common *node = NODE(t, off, trie_common); |
579 | if (node->type == TRIE_LEAF) { |
580 | assert(depth > 0 && buf[depth-1] == '\0'); |
581 | return; |
582 | } else if (node->type == TRIE_STRING) { |
583 | const struct trie_string *st = NODE(t, off, trie_string); |
584 | |
585 | memcpy(buf + depth, st->string, st->stringlen); |
586 | depth += st->stringlen; |
587 | off = st->subnode; |
588 | } else if (node->type == TRIE_SWITCH) { |
589 | const struct trie_switch *sw = NODE(t, off, trie_switch); |
590 | const char *chars = (const char *)&sw->sw[sw->len]; |
591 | int i; |
592 | |
593 | for (i = 0; i < sw->len; i++) { |
594 | if (n < sw->sw[i].subcount) { |
595 | buf[depth++] = chars[i]; |
596 | off = sw->sw[i].subnode; |
597 | break; |
598 | } else |
599 | n -= sw->sw[i].subcount; |
600 | } |
601 | assert(i < sw->len); |
602 | } |
603 | } |
604 | } |
605 | |
606 | unsigned long trie_count(const void *t) |
607 | { |
608 | const struct trie_header *hdr = NODE(t, 0, trie_header); |
609 | return hdr->count; |
610 | } |
611 | |
269fa2d1 |
612 | char trie_pathsep(const void *t) |
613 | { |
614 | const struct trie_header *hdr = NODE(t, 0, trie_header); |
615 | return (char)hdr->pathsep; |
616 | } |
617 | |
70322ae3 |
618 | struct triewalk_switch { |
619 | const struct trie_switch *sw; |
620 | int pos, depth, count; |
621 | }; |
622 | struct triewalk { |
623 | const void *t; |
624 | struct triewalk_switch *switches; |
625 | int nswitches, switchsize; |
626 | int count; |
627 | }; |
628 | triewalk *triewalk_new(const void *vt) |
629 | { |
630 | triewalk *tw = snew(triewalk); |
631 | |
632 | tw->t = (const char *)vt; |
633 | tw->switches = NULL; |
634 | tw->switchsize = 0; |
635 | tw->nswitches = -1; |
636 | tw->count = 0; |
637 | |
638 | return tw; |
639 | } |
640 | const struct trie_file *triewalk_next(triewalk *tw, char *buf) |
641 | { |
642 | off_t off; |
643 | int depth; |
644 | |
645 | if (tw->nswitches < 0) { |
646 | const struct trie_header *hdr = NODE(tw->t, 0, trie_header); |
647 | off = hdr->root; |
648 | depth = 0; |
649 | tw->nswitches = 0; |
650 | } else { |
651 | while (1) { |
652 | int swpos; |
653 | const struct trie_switch *sw; |
654 | const char *chars; |
655 | |
656 | if (tw->nswitches == 0) { |
657 | assert(tw->count == NODE(tw->t, 0, trie_header)->count); |
658 | return NULL; /* run out of trie */ |
659 | } |
660 | |
661 | swpos = tw->switches[tw->nswitches-1].pos; |
662 | sw = tw->switches[tw->nswitches-1].sw; |
663 | chars = (const char *)&sw->sw[sw->len]; |
664 | |
665 | if (swpos < sw->len) { |
666 | depth = tw->switches[tw->nswitches-1].depth; |
667 | off = sw->sw[swpos].subnode; |
668 | if (buf) |
669 | buf[depth++] = chars[swpos]; |
670 | assert(tw->count == tw->switches[tw->nswitches-1].count); |
671 | tw->switches[tw->nswitches-1].count += sw->sw[swpos].subcount; |
672 | tw->switches[tw->nswitches-1].pos++; |
673 | break; |
674 | } |
675 | |
676 | tw->nswitches--; |
677 | } |
678 | } |
679 | |
680 | while (1) { |
681 | const struct trie_common *node = NODE(tw->t, off, trie_common); |
682 | if (node->type == TRIE_LEAF) { |
683 | const struct trie_leaf *lf = NODE(tw->t, off, trie_leaf); |
684 | if (buf) |
685 | assert(depth > 0 && buf[depth-1] == '\0'); |
686 | tw->count++; |
687 | return &lf->file; |
688 | } else if (node->type == TRIE_STRING) { |
689 | const struct trie_string *st = NODE(tw->t, off, trie_string); |
690 | |
691 | if (buf) |
692 | memcpy(buf + depth, st->string, st->stringlen); |
693 | depth += st->stringlen; |
694 | off = st->subnode; |
695 | } else if (node->type == TRIE_SWITCH) { |
696 | const struct trie_switch *sw = NODE(tw->t, off, trie_switch); |
697 | const char *chars = (const char *)&sw->sw[sw->len]; |
698 | |
699 | if (tw->nswitches >= tw->switchsize) { |
700 | tw->switchsize = tw->nswitches * 3 / 2 + 32; |
701 | tw->switches = sresize(tw->switches, tw->switchsize, |
702 | struct triewalk_switch); |
703 | } |
704 | |
705 | tw->switches[tw->nswitches].sw = sw; |
706 | tw->switches[tw->nswitches].pos = 1; |
707 | tw->switches[tw->nswitches].depth = depth; |
708 | tw->switches[tw->nswitches].count = tw->count + sw->sw[0].subcount; |
709 | off = sw->sw[0].subnode; |
710 | if (buf) |
711 | buf[depth++] = chars[0]; |
712 | tw->nswitches++; |
713 | } |
714 | } |
715 | } |
716 | void triewalk_free(triewalk *tw) |
717 | { |
718 | sfree(tw->switches); |
719 | sfree(tw); |
720 | } |
721 | |
722 | void trie_set_index_offset(void *t, off_t ptr) |
723 | { |
724 | ((struct trie_header *)t)->indexroot = ptr; |
725 | } |
726 | off_t trie_get_index_offset(const void *t) |
727 | { |
728 | return ((const struct trie_header *)t)->indexroot; |
729 | } |
256c29a2 |
730 | |
731 | void make_successor(char *pathbuf) |
732 | { |
733 | int len = strlen(pathbuf); |
734 | if (len > 0 && pathbuf[len-1] == pathsep) |
735 | len--; |
736 | pathbuf[len] = '\001'; |
737 | pathbuf[len+1] = '\0'; |
738 | } |