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Commit | Line | Data |
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74986462 JH |
1 | #include "cache.h" |
2 | #include "tree.h" | |
3 | #include "cache-tree.h" | |
4 | ||
5 | #define DEBUG 0 | |
6 | ||
7 | struct cache_tree *cache_tree(void) | |
8 | { | |
9 | struct cache_tree *it = xcalloc(1, sizeof(struct cache_tree)); | |
10 | it->entry_count = -1; | |
11 | return it; | |
12 | } | |
13 | ||
14 | void cache_tree_free(struct cache_tree *it) | |
15 | { | |
16 | int i; | |
17 | ||
18 | if (!it) | |
19 | return; | |
20 | for (i = 0; i < it->subtree_nr; i++) | |
21 | cache_tree_free(it->down[i]->cache_tree); | |
22 | free(it->down); | |
23 | free(it); | |
24 | } | |
25 | ||
26 | static struct cache_tree_sub *find_subtree(struct cache_tree *it, | |
27 | const char *path, | |
28 | int pathlen, | |
29 | int create) | |
30 | { | |
31 | int i; | |
32 | struct cache_tree_sub *down; | |
33 | for (i = 0; i < it->subtree_nr; i++) { | |
34 | down = it->down[i]; | |
35 | if (down->namelen == pathlen && | |
36 | !memcmp(down->name, path, pathlen)) | |
37 | return down; | |
38 | } | |
39 | if (!create) | |
40 | return NULL; | |
41 | if (it->subtree_alloc <= it->subtree_nr) { | |
42 | it->subtree_alloc = alloc_nr(it->subtree_alloc); | |
43 | it->down = xrealloc(it->down, it->subtree_alloc * | |
44 | sizeof(*it->down)); | |
45 | } | |
46 | down = xmalloc(sizeof(*down) + pathlen + 1); | |
47 | down->cache_tree = NULL; /* cache_tree(); */ | |
48 | down->namelen = pathlen; | |
49 | memcpy(down->name, path, pathlen); | |
50 | down->name[pathlen] = 0; /* not strictly needed */ | |
51 | it->down[it->subtree_nr++] = down; | |
52 | return down; | |
53 | } | |
54 | ||
55 | void cache_tree_invalidate_path(struct cache_tree *it, const char *path) | |
56 | { | |
57 | /* a/b/c | |
58 | * ==> invalidate self | |
59 | * ==> find "a", have it invalidate "b/c" | |
60 | * a | |
61 | * ==> invalidate self | |
62 | * ==> if "a" exists as a subtree, remove it. | |
63 | */ | |
64 | const char *slash; | |
65 | int namelen; | |
66 | struct cache_tree_sub *down; | |
67 | ||
68 | if (!it) | |
69 | return; | |
70 | slash = strchr(path, '/'); | |
71 | it->entry_count = -1; | |
72 | if (!slash) { | |
73 | int i; | |
74 | namelen = strlen(path); | |
75 | for (i = 0; i < it->subtree_nr; i++) { | |
76 | if (it->down[i]->namelen == namelen && | |
77 | !memcmp(it->down[i]->name, path, namelen)) | |
78 | break; | |
79 | } | |
80 | if (i < it->subtree_nr) { | |
81 | cache_tree_free(it->down[i]->cache_tree); | |
82 | free(it->down[i]); | |
83 | /* 0 1 2 3 4 5 | |
84 | * ^ ^subtree_nr = 6 | |
85 | * i | |
86 | * move 4 and 5 up one place (2 entries) | |
87 | * 2 = 6 - 3 - 1 = subtree_nr - i - 1 | |
88 | */ | |
89 | memmove(it->down+i, it->down+i+1, | |
90 | sizeof(struct cache_tree_sub *) * | |
91 | (it->subtree_nr - i - 1)); | |
92 | it->subtree_nr--; | |
93 | } | |
94 | return; | |
95 | } | |
96 | namelen = slash - path; | |
97 | down = find_subtree(it, path, namelen, 0); | |
98 | if (down) | |
99 | cache_tree_invalidate_path(down->cache_tree, slash + 1); | |
100 | } | |
101 | ||
102 | static int verify_cache(struct cache_entry **cache, | |
103 | int entries) | |
104 | { | |
105 | int i, funny; | |
106 | ||
107 | /* Verify that the tree is merged */ | |
108 | funny = 0; | |
109 | for (i = 0; i < entries; i++) { | |
110 | struct cache_entry *ce = cache[i]; | |
111 | if (ce_stage(ce)) { | |
112 | if (10 < ++funny) { | |
113 | fprintf(stderr, "...\n"); | |
114 | break; | |
115 | } | |
116 | fprintf(stderr, "%s: unmerged (%s)\n", | |
117 | ce->name, sha1_to_hex(ce->sha1)); | |
118 | } | |
119 | } | |
120 | if (funny) | |
121 | return -1; | |
122 | ||
123 | /* Also verify that the cache does not have path and path/file | |
124 | * at the same time. At this point we know the cache has only | |
125 | * stage 0 entries. | |
126 | */ | |
127 | funny = 0; | |
128 | for (i = 0; i < entries - 1; i++) { | |
129 | /* path/file always comes after path because of the way | |
130 | * the cache is sorted. Also path can appear only once, | |
131 | * which means conflicting one would immediately follow. | |
132 | */ | |
133 | const char *this_name = cache[i]->name; | |
134 | const char *next_name = cache[i+1]->name; | |
135 | int this_len = strlen(this_name); | |
136 | if (this_len < strlen(next_name) && | |
137 | strncmp(this_name, next_name, this_len) == 0 && | |
138 | next_name[this_len] == '/') { | |
139 | if (10 < ++funny) { | |
140 | fprintf(stderr, "...\n"); | |
141 | break; | |
142 | } | |
143 | fprintf(stderr, "You have both %s and %s\n", | |
144 | this_name, next_name); | |
145 | } | |
146 | } | |
147 | if (funny) | |
148 | return -1; | |
149 | return 0; | |
150 | } | |
151 | ||
152 | static void discard_unused_subtrees(struct cache_tree *it) | |
153 | { | |
154 | struct cache_tree_sub **down = it->down; | |
155 | int nr = it->subtree_nr; | |
156 | int dst, src; | |
157 | for (dst = src = 0; src < nr; src++) { | |
158 | struct cache_tree_sub *s = down[src]; | |
159 | if (s->used) | |
160 | down[dst++] = s; | |
161 | else { | |
162 | cache_tree_free(s->cache_tree); | |
163 | free(s); | |
164 | it->subtree_nr--; | |
165 | } | |
166 | } | |
167 | } | |
168 | ||
169 | static int update_one(struct cache_tree *it, | |
170 | struct cache_entry **cache, | |
171 | int entries, | |
172 | const char *base, | |
173 | int baselen, | |
174 | int missing_ok) | |
175 | { | |
176 | unsigned long size, offset; | |
177 | char *buffer; | |
178 | int i; | |
179 | ||
180 | if (0 <= it->entry_count) | |
181 | return it->entry_count; | |
182 | ||
183 | /* | |
184 | * We first scan for subtrees and update them; we start by | |
185 | * marking existing subtrees -- the ones that are unmarked | |
186 | * should not be in the result. | |
187 | */ | |
188 | for (i = 0; i < it->subtree_nr; i++) | |
189 | it->down[i]->used = 0; | |
190 | ||
191 | /* | |
192 | * Find the subtrees and update them. | |
193 | */ | |
194 | for (i = 0; i < entries; i++) { | |
195 | struct cache_entry *ce = cache[i]; | |
196 | struct cache_tree_sub *sub; | |
197 | const char *path, *slash; | |
198 | int pathlen, sublen, subcnt; | |
199 | ||
200 | path = ce->name; | |
201 | pathlen = ce_namelen(ce); | |
202 | if (pathlen <= baselen || memcmp(base, path, baselen)) | |
203 | break; /* at the end of this level */ | |
204 | ||
205 | slash = strchr(path + baselen, '/'); | |
206 | if (!slash) | |
207 | continue; | |
208 | /* | |
209 | * a/bbb/c (base = a/, slash = /c) | |
210 | * ==> | |
211 | * path+baselen = bbb/c, sublen = 3 | |
212 | */ | |
213 | sublen = slash - (path + baselen); | |
214 | sub = find_subtree(it, path + baselen, sublen, 1); | |
215 | if (!sub->cache_tree) | |
216 | sub->cache_tree = cache_tree(); | |
217 | subcnt = update_one(sub->cache_tree, | |
218 | cache + i, entries - i, | |
219 | path, | |
220 | baselen + sublen + 1, | |
221 | missing_ok); | |
222 | i += subcnt - 1; | |
223 | sub->used = 1; | |
224 | } | |
225 | ||
226 | discard_unused_subtrees(it); | |
227 | ||
228 | /* | |
229 | * Then write out the tree object for this level. | |
230 | */ | |
231 | size = 8192; | |
232 | buffer = xmalloc(size); | |
233 | offset = 0; | |
234 | ||
235 | for (i = 0; i < entries; i++) { | |
236 | struct cache_entry *ce = cache[i]; | |
237 | struct cache_tree_sub *sub; | |
238 | const char *path, *slash; | |
239 | int pathlen, entlen; | |
240 | const unsigned char *sha1; | |
241 | unsigned mode; | |
242 | ||
243 | path = ce->name; | |
244 | pathlen = ce_namelen(ce); | |
245 | if (pathlen <= baselen || memcmp(base, path, baselen)) | |
246 | break; /* at the end of this level */ | |
247 | ||
248 | slash = strchr(path + baselen, '/'); | |
249 | if (slash) { | |
250 | entlen = slash - (path + baselen); | |
251 | sub = find_subtree(it, path + baselen, entlen, 0); | |
252 | if (!sub) | |
253 | die("cache-tree.c: '%.*s' in '%s' not found", | |
254 | entlen, path + baselen, path); | |
255 | i += sub->cache_tree->entry_count - 1; | |
256 | sha1 = sub->cache_tree->sha1; | |
257 | mode = S_IFDIR; | |
258 | } | |
259 | else { | |
260 | sha1 = ce->sha1; | |
261 | mode = ntohl(ce->ce_mode); | |
262 | entlen = pathlen - baselen; | |
263 | } | |
264 | if (!missing_ok && !has_sha1_file(sha1)) | |
265 | return error("invalid object %s", sha1_to_hex(sha1)); | |
266 | ||
267 | if (!ce->ce_mode) | |
268 | continue; /* entry being removed */ | |
269 | ||
270 | if (size < offset + entlen + 100) { | |
271 | size = alloc_nr(offset + entlen + 100); | |
272 | buffer = xrealloc(buffer, size); | |
273 | } | |
274 | offset += sprintf(buffer + offset, | |
275 | "%o %.*s", mode, entlen, path + baselen); | |
276 | buffer[offset++] = 0; | |
277 | memcpy(buffer + offset, sha1, 20); | |
278 | offset += 20; | |
279 | ||
280 | #if DEBUG | |
281 | fprintf(stderr, "cache-tree %o %.*s\n", | |
282 | mode, entlen, path + baselen); | |
283 | #endif | |
284 | } | |
285 | ||
286 | write_sha1_file(buffer, offset, tree_type, it->sha1); | |
287 | free(buffer); | |
288 | it->entry_count = i; | |
289 | #if DEBUG | |
290 | fprintf(stderr, "cache-tree (%d ent, %d subtree) %s\n", | |
291 | it->entry_count, it->subtree_nr, | |
292 | sha1_to_hex(it->sha1)); | |
293 | #endif | |
294 | return i; | |
295 | } | |
296 | ||
297 | int cache_tree_update(struct cache_tree *it, | |
298 | struct cache_entry **cache, | |
299 | int entries, | |
300 | int missing_ok) | |
301 | { | |
302 | int i; | |
303 | i = verify_cache(cache, entries); | |
304 | if (i) | |
305 | return i; | |
306 | i = update_one(it, cache, entries, "", 0, missing_ok); | |
307 | if (i < 0) | |
308 | return i; | |
309 | return 0; | |
310 | } | |
311 | ||
312 | static void *write_one(struct cache_tree *it, | |
313 | char *path, | |
314 | int pathlen, | |
315 | char *buffer, | |
316 | unsigned long *size, | |
317 | unsigned long *offset) | |
318 | { | |
319 | int i; | |
320 | ||
321 | /* One "cache-tree" entry consists of the following: | |
322 | * path (NUL terminated) | |
323 | * entry_count, subtree_nr ("%d %d\n") | |
324 | * tree-sha1 (missing if invalid) | |
325 | * subtree_nr "cache-tree" entries for subtrees. | |
326 | */ | |
327 | if (*size < *offset + pathlen + 100) { | |
328 | *size = alloc_nr(*offset + pathlen + 100); | |
329 | buffer = xrealloc(buffer, *size); | |
330 | } | |
331 | *offset += sprintf(buffer + *offset, "%.*s%c%d %d\n", | |
332 | pathlen, path, 0, | |
333 | it->entry_count, it->subtree_nr); | |
334 | ||
335 | #if DEBUG | |
336 | if (0 <= it->entry_count) | |
337 | fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n", | |
338 | pathlen, path, it->entry_count, it->subtree_nr, | |
339 | sha1_to_hex(it->sha1)); | |
340 | else | |
341 | fprintf(stderr, "cache-tree <%.*s> (%d subtree) invalid\n", | |
342 | pathlen, path, it->subtree_nr); | |
343 | #endif | |
344 | ||
345 | if (0 <= it->entry_count) { | |
346 | memcpy(buffer + *offset, it->sha1, 20); | |
347 | *offset += 20; | |
348 | } | |
349 | for (i = 0; i < it->subtree_nr; i++) { | |
350 | struct cache_tree_sub *down = it->down[i]; | |
351 | buffer = write_one(down->cache_tree, down->name, down->namelen, | |
352 | buffer, size, offset); | |
353 | } | |
354 | return buffer; | |
355 | } | |
356 | ||
357 | static void *cache_tree_write(const unsigned char *cache_sha1, | |
358 | struct cache_tree *root, | |
359 | unsigned long *offset_p) | |
360 | { | |
361 | char path[PATH_MAX]; | |
362 | unsigned long size = 8192; | |
363 | char *buffer = xmalloc(size); | |
364 | ||
365 | /* the cache checksum of the corresponding index file. */ | |
366 | memcpy(buffer, cache_sha1, 20); | |
367 | *offset_p = 20; | |
368 | path[0] = 0; | |
369 | return write_one(root, path, 0, buffer, &size, offset_p); | |
370 | } | |
371 | ||
372 | static struct cache_tree *read_one(const char **buffer, unsigned long *size_p) | |
373 | { | |
374 | const char *buf = *buffer; | |
375 | unsigned long size = *size_p; | |
376 | struct cache_tree *it; | |
377 | int i, subtree_nr; | |
378 | ||
379 | it = NULL; | |
380 | /* skip name, but make sure name exists */ | |
381 | while (size && *buf) { | |
382 | size--; | |
383 | buf++; | |
384 | } | |
385 | if (!size) | |
386 | goto free_return; | |
387 | buf++; size--; | |
388 | it = cache_tree(); | |
389 | if (sscanf(buf, "%d %d\n", &it->entry_count, &subtree_nr) != 2) | |
390 | goto free_return; | |
391 | while (size && *buf && *buf != '\n') { | |
392 | size--; | |
393 | buf++; | |
394 | } | |
395 | if (!size) | |
396 | goto free_return; | |
397 | buf++; size--; | |
398 | if (0 <= it->entry_count) { | |
399 | if (size < 20) | |
400 | goto free_return; | |
401 | memcpy(it->sha1, buf, 20); | |
402 | buf += 20; | |
403 | size -= 20; | |
404 | } | |
405 | ||
406 | #if DEBUG | |
407 | if (0 <= it->entry_count) | |
408 | fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n", | |
409 | *buffer, it->entry_count, subtree_nr, | |
410 | sha1_to_hex(it->sha1)); | |
411 | else | |
412 | fprintf(stderr, "cache-tree <%s> (%d subtrees) invalid\n", | |
413 | *buffer, subtree_nr); | |
414 | #endif | |
415 | ||
416 | /* | |
417 | * Just a heuristic -- we do not add directories that often but | |
418 | * we do not want to have to extend it immediately when we do, | |
419 | * hence +2. | |
420 | */ | |
421 | it->subtree_alloc = subtree_nr + 2; | |
422 | it->down = xcalloc(it->subtree_alloc, sizeof(struct cache_tree_sub *)); | |
423 | for (i = 0; i < subtree_nr; i++) { | |
424 | /* read each subtree */ | |
425 | struct cache_tree *sub; | |
426 | const char *name = buf; | |
427 | int namelen; | |
428 | sub = read_one(&buf, &size); | |
429 | if (!sub) | |
430 | goto free_return; | |
431 | namelen = strlen(name); | |
432 | it->down[i] = find_subtree(it, name, namelen, 1); | |
433 | it->down[i]->cache_tree = sub; | |
434 | } | |
435 | if (subtree_nr != it->subtree_nr) | |
436 | die("cache-tree: internal error"); | |
437 | *buffer = buf; | |
438 | *size_p = size; | |
439 | return it; | |
440 | ||
441 | free_return: | |
442 | cache_tree_free(it); | |
443 | return NULL; | |
444 | } | |
445 | ||
446 | static struct cache_tree *cache_tree_read(unsigned char *sha1, | |
447 | const char *buffer, | |
448 | unsigned long size) | |
449 | { | |
450 | /* check the cache-tree matches the index */ | |
451 | if (memcmp(buffer, sha1, 20)) | |
452 | return NULL; /* checksum mismatch */ | |
453 | if (buffer[20]) | |
454 | return NULL; /* not the whole tree */ | |
455 | buffer += 20; | |
456 | size -= 20; | |
457 | return read_one(&buffer, &size); | |
458 | } | |
459 | ||
460 | struct cache_tree *read_cache_tree(unsigned char *sha1) | |
461 | { | |
462 | int fd; | |
463 | struct stat st; | |
464 | char path[PATH_MAX]; | |
465 | unsigned long size = 0; | |
466 | void *map; | |
467 | struct cache_tree *it; | |
468 | ||
469 | sprintf(path, "%s.aux", get_index_file()); | |
470 | fd = open(path, O_RDONLY); | |
471 | if (fd < 0) | |
472 | return cache_tree(); | |
473 | ||
474 | if (fstat(fd, &st)) | |
475 | return cache_tree(); | |
476 | size = st.st_size; | |
477 | map = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0); | |
478 | close(fd); | |
479 | if (map == MAP_FAILED) | |
480 | return cache_tree(); | |
481 | it = cache_tree_read(sha1, map, size); | |
482 | munmap(map, size); | |
483 | if (!it) | |
484 | return cache_tree(); | |
485 | return it; | |
486 | } | |
487 | ||
488 | int write_cache_tree(const unsigned char *sha1, struct cache_tree *root) | |
489 | { | |
490 | char path[PATH_MAX]; | |
491 | unsigned long size = 0; | |
492 | void *buf, *buffer; | |
493 | int fd, ret = -1; | |
494 | ||
495 | sprintf(path, "%s.aux", get_index_file()); | |
496 | if (!root) { | |
497 | unlink(path); | |
498 | return -1; | |
499 | } | |
500 | fd = open(path, O_WRONLY|O_CREAT, 0666); | |
501 | if (fd < 0) | |
502 | return -1; | |
503 | buffer = buf = cache_tree_write(sha1, root, &size); | |
504 | while (size) { | |
505 | int written = xwrite(fd, buf, size); | |
506 | if (written <= 0) | |
507 | goto fail; | |
508 | buf += written; | |
509 | size -= written; | |
510 | } | |
511 | ret = 0; | |
512 | ||
513 | fail: | |
514 | close(fd); | |
515 | free(buffer); | |
516 | if (ret) | |
517 | unlink(path); | |
518 | return ret; | |
519 | } |