1#include "cache.h"
2#include "tree.h"
3#include "tree-walk.h"
4#include "cache-tree.h"
5#ifndef DEBUG
7#define DEBUG 0
8#endif
9struct cache_tree *cache_tree(void)
11{
12 struct cache_tree *it = xcalloc(1, sizeof(struct cache_tree));
13 it->entry_count = -1;
14 return it;
15}
16void cache_tree_free(struct cache_tree **it_p)
18{
19 int i;
20 struct cache_tree *it = *it_p;
21 if (!it)
23 return;
24 for (i = 0; i < it->subtree_nr; i++)
25 if (it->down[i]) {
26 cache_tree_free(&it->down[i]->cache_tree);
27 free(it->down[i]);
28 }
29 free(it->down);
30 free(it);
31 *it_p = NULL;
32}
33static int subtree_name_cmp(const char *one, int onelen,
35 const char *two, int twolen)
36{
37 if (onelen < twolen)
38 return -1;
39 if (twolen < onelen)
40 return 1;
41 return memcmp(one, two, onelen);
42}
43static int subtree_pos(struct cache_tree *it, const char *path, int pathlen)
45{
46 struct cache_tree_sub **down = it->down;
47 int lo, hi;
48 lo = 0;
49 hi = it->subtree_nr;
50 while (lo < hi) {
51 int mi = (lo + hi) / 2;
52 struct cache_tree_sub *mdl = down[mi];
53 int cmp = subtree_name_cmp(path, pathlen,
54 mdl->name, mdl->namelen);
55 if (!cmp)
56 return mi;
57 if (cmp < 0)
58 hi = mi;
59 else
60 lo = mi + 1;
61 }
62 return -lo-1;
63}
64static struct cache_tree_sub *find_subtree(struct cache_tree *it,
66 const char *path,
67 int pathlen,
68 int create)
69{
70 struct cache_tree_sub *down;
71 int pos = subtree_pos(it, path, pathlen);
72 if (0 <= pos)
73 return it->down[pos];
74 if (!create)
75 return NULL;
76 pos = -pos-1;
78 if (it->subtree_alloc <= it->subtree_nr) {
79 it->subtree_alloc = alloc_nr(it->subtree_alloc);
80 it->down = xrealloc(it->down, it->subtree_alloc *
81 sizeof(*it->down));
82 }
83 it->subtree_nr++;
84 down = xmalloc(sizeof(*down) + pathlen + 1);
86 down->cache_tree = NULL;
87 down->namelen = pathlen;
88 memcpy(down->name, path, pathlen);
89 down->name[pathlen] = 0;
90 if (pos < it->subtree_nr)
92 memmove(it->down + pos + 1,
93 it->down + pos,
94 sizeof(down) * (it->subtree_nr - pos - 1));
95 it->down[pos] = down;
96 return down;
97}
98struct cache_tree_sub *cache_tree_sub(struct cache_tree *it, const char *path)
100{
101 int pathlen = strlen(path);
102 return find_subtree(it, path, pathlen, 1);
103}
104void cache_tree_invalidate_path(struct cache_tree *it, const char *path)
106{
107 /* a/b/c
108 * ==> invalidate self
109 * ==> find "a", have it invalidate "b/c"
110 * a
111 * ==> invalidate self
112 * ==> if "a" exists as a subtree, remove it.
113 */
114 const char *slash;
115 int namelen;
116 struct cache_tree_sub *down;
117#if DEBUG
119 fprintf(stderr, "cache-tree invalidate <%s>\n", path);
120#endif
121 if (!it)
123 return;
124 slash = strchr(path, '/');
125 it->entry_count = -1;
126 if (!slash) {
127 int pos;
128 namelen = strlen(path);
129 pos = subtree_pos(it, path, namelen);
130 if (0 <= pos) {
131 cache_tree_free(&it->down[pos]->cache_tree);
132 free(it->down[pos]);
133 /* 0 1 2 3 4 5
134 * ^ ^subtree_nr = 6
135 * pos
136 * move 4 and 5 up one place (2 entries)
137 * 2 = 6 - 3 - 1 = subtree_nr - pos - 1
138 */
139 memmove(it->down+pos, it->down+pos+1,
140 sizeof(struct cache_tree_sub *) *
141 (it->subtree_nr - pos - 1));
142 it->subtree_nr--;
143 }
144 return;
145 }
146 namelen = slash - path;
147 down = find_subtree(it, path, namelen, 0);
148 if (down)
149 cache_tree_invalidate_path(down->cache_tree, slash + 1);
150}
151static int verify_cache(struct cache_entry **cache,
153 int entries, int silent)
154{
155 int i, funny;
156 /* Verify that the tree is merged */
158 funny = 0;
159 for (i = 0; i < entries; i++) {
160 struct cache_entry *ce = cache[i];
161 if (ce_stage(ce) || (ce->ce_flags & CE_INTENT_TO_ADD)) {
162 if (silent)
163 return -1;
164 if (10 < ++funny) {
165 fprintf(stderr, "...\n");
166 break;
167 }
168 if (ce_stage(ce))
169 fprintf(stderr, "%s: unmerged (%s)\n",
170 ce->name, sha1_to_hex(ce->sha1));
171 else
172 fprintf(stderr, "%s: not added yet\n",
173 ce->name);
174 }
175 }
176 if (funny)
177 return -1;
178 /* Also verify that the cache does not have path and path/file
180 * at the same time. At this point we know the cache has only
181 * stage 0 entries.
182 */
183 funny = 0;
184 for (i = 0; i < entries - 1; i++) {
185 /* path/file always comes after path because of the way
186 * the cache is sorted. Also path can appear only once,
187 * which means conflicting one would immediately follow.
188 */
189 const char *this_name = cache[i]->name;
190 const char *next_name = cache[i+1]->name;
191 int this_len = strlen(this_name);
192 if (this_len < strlen(next_name) &&
193 strncmp(this_name, next_name, this_len) == 0 &&
194 next_name[this_len] == '/') {
195 if (10 < ++funny) {
196 fprintf(stderr, "...\n");
197 break;
198 }
199 fprintf(stderr, "You have both %s and %s\n",
200 this_name, next_name);
201 }
202 }
203 if (funny)
204 return -1;
205 return 0;
206}
207static void discard_unused_subtrees(struct cache_tree *it)
209{
210 struct cache_tree_sub **down = it->down;
211 int nr = it->subtree_nr;
212 int dst, src;
213 for (dst = src = 0; src < nr; src++) {
214 struct cache_tree_sub *s = down[src];
215 if (s->used)
216 down[dst++] = s;
217 else {
218 cache_tree_free(&s->cache_tree);
219 free(s);
220 it->subtree_nr--;
221 }
222 }
223}
224int cache_tree_fully_valid(struct cache_tree *it)
226{
227 int i;
228 if (!it)
229 return 0;
230 if (it->entry_count < 0 || !has_sha1_file(it->sha1))
231 return 0;
232 for (i = 0; i < it->subtree_nr; i++) {
233 if (!cache_tree_fully_valid(it->down[i]->cache_tree))
234 return 0;
235 }
236 return 1;
237}
238static int update_one(struct cache_tree *it,
240 struct cache_entry **cache,
241 int entries,
242 const char *base,
243 int baselen,
244 int missing_ok,
245 int dryrun)
246{
247 struct strbuf buffer;
248 int i;
249 if (0 <= it->entry_count && has_sha1_file(it->sha1))
251 return it->entry_count;
252 /*
254 * We first scan for subtrees and update them; we start by
255 * marking existing subtrees -- the ones that are unmarked
256 * should not be in the result.
257 */
258 for (i = 0; i < it->subtree_nr; i++)
259 it->down[i]->used = 0;
260 /*
262 * Find the subtrees and update them.
263 */
264 for (i = 0; i < entries; i++) {
265 struct cache_entry *ce = cache[i];
266 struct cache_tree_sub *sub;
267 const char *path, *slash;
268 int pathlen, sublen, subcnt;
269 path = ce->name;
271 pathlen = ce_namelen(ce);
272 if (pathlen <= baselen || memcmp(base, path, baselen))
273 break; /* at the end of this level */
274 slash = strchr(path + baselen, '/');
276 if (!slash)
277 continue;
278 /*
279 * a/bbb/c (base = a/, slash = /c)
280 * ==>
281 * path+baselen = bbb/c, sublen = 3
282 */
283 sublen = slash - (path + baselen);
284 sub = find_subtree(it, path + baselen, sublen, 1);
285 if (!sub->cache_tree)
286 sub->cache_tree = cache_tree();
287 subcnt = update_one(sub->cache_tree,
288 cache + i, entries - i,
289 path,
290 baselen + sublen + 1,
291 missing_ok,
292 dryrun);
293 if (subcnt < 0)
294 return subcnt;
295 i += subcnt - 1;
296 sub->used = 1;
297 }
298 discard_unused_subtrees(it);
300 /*
302 * Then write out the tree object for this level.
303 */
304 strbuf_init(&buffer, 8192);
305 for (i = 0; i < entries; i++) {
307 struct cache_entry *ce = cache[i];
308 struct cache_tree_sub *sub;
309 const char *path, *slash;
310 int pathlen, entlen;
311 const unsigned char *sha1;
312 unsigned mode;
313 path = ce->name;
315 pathlen = ce_namelen(ce);
316 if (pathlen <= baselen || memcmp(base, path, baselen))
317 break; /* at the end of this level */
318 slash = strchr(path + baselen, '/');
320 if (slash) {
321 entlen = slash - (path + baselen);
322 sub = find_subtree(it, path + baselen, entlen, 0);
323 if (!sub)
324 die("cache-tree.c: '%.*s' in '%s' not found",
325 entlen, path + baselen, path);
326 i += sub->cache_tree->entry_count - 1;
327 sha1 = sub->cache_tree->sha1;
328 mode = S_IFDIR;
329 }
330 else {
331 sha1 = ce->sha1;
332 mode = ce->ce_mode;
333 entlen = pathlen - baselen;
334 }
335 if (mode != S_IFGITLINK && !missing_ok && !has_sha1_file(sha1)) {
336 strbuf_release(&buffer);
337 return error("invalid object %06o %s for '%.*s'",
338 mode, sha1_to_hex(sha1), entlen+baselen, path);
339 }
340 if (ce->ce_flags & CE_REMOVE)
342 continue; /* entry being removed */
343 strbuf_grow(&buffer, entlen + 100);
345 strbuf_addf(&buffer, "%o %.*s%c", mode, entlen, path + baselen, '\0');
346 strbuf_add(&buffer, sha1, 20);
347#if DEBUG
349 fprintf(stderr, "cache-tree update-one %o %.*s\n",
350 mode, entlen, path + baselen);
351#endif
352 }
353 if (dryrun)
355 hash_sha1_file(buffer.buf, buffer.len, tree_type, it->sha1);
356 else if (write_sha1_file(buffer.buf, buffer.len, tree_type, it->sha1)) {
357 strbuf_release(&buffer);
358 return -1;
359 }
360 strbuf_release(&buffer);
362 it->entry_count = i;
363#if DEBUG
364 fprintf(stderr, "cache-tree update-one (%d ent, %d subtree) %s\n",
365 it->entry_count, it->subtree_nr,
366 sha1_to_hex(it->sha1));
367#endif
368 return i;
369}
370int cache_tree_update(struct cache_tree *it,
372 struct cache_entry **cache,
373 int entries,
374 int missing_ok,
375 int dryrun,
376 int silent)
377{
378 int i;
379 i = verify_cache(cache, entries, silent);
380 if (i)
381 return i;
382 i = update_one(it, cache, entries, "", 0, missing_ok, dryrun);
383 if (i < 0)
384 return i;
385 return 0;
386}
387static void write_one(struct strbuf *buffer, struct cache_tree *it,
389 const char *path, int pathlen)
390{
391 int i;
392 /* One "cache-tree" entry consists of the following:
394 * path (NUL terminated)
395 * entry_count, subtree_nr ("%d %d\n")
396 * tree-sha1 (missing if invalid)
397 * subtree_nr "cache-tree" entries for subtrees.
398 */
399 strbuf_grow(buffer, pathlen + 100);
400 strbuf_add(buffer, path, pathlen);
401 strbuf_addf(buffer, "%c%d %d\n", 0, it->entry_count, it->subtree_nr);
402#if DEBUG
404 if (0 <= it->entry_count)
405 fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n",
406 pathlen, path, it->entry_count, it->subtree_nr,
407 sha1_to_hex(it->sha1));
408 else
409 fprintf(stderr, "cache-tree <%.*s> (%d subtree) invalid\n",
410 pathlen, path, it->subtree_nr);
411#endif
412 if (0 <= it->entry_count) {
414 strbuf_add(buffer, it->sha1, 20);
415 }
416 for (i = 0; i < it->subtree_nr; i++) {
417 struct cache_tree_sub *down = it->down[i];
418 if (i) {
419 struct cache_tree_sub *prev = it->down[i-1];
420 if (subtree_name_cmp(down->name, down->namelen,
421 prev->name, prev->namelen) <= 0)
422 die("fatal - unsorted cache subtree");
423 }
424 write_one(buffer, down->cache_tree, down->name, down->namelen);
425 }
426}
427void cache_tree_write(struct strbuf *sb, struct cache_tree *root)
429{
430 write_one(sb, root, "", 0);
431}
432static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
434{
435 const char *buf = *buffer;
436 unsigned long size = *size_p;
437 const char *cp;
438 char *ep;
439 struct cache_tree *it;
440 int i, subtree_nr;
441 it = NULL;
443 /* skip name, but make sure name exists */
444 while (size && *buf) {
445 size--;
446 buf++;
447 }
448 if (!size)
449 goto free_return;
450 buf++; size--;
451 it = cache_tree();
452 cp = buf;
454 it->entry_count = strtol(cp, &ep, 10);
455 if (cp == ep)
456 goto free_return;
457 cp = ep;
458 subtree_nr = strtol(cp, &ep, 10);
459 if (cp == ep)
460 goto free_return;
461 while (size && *buf && *buf != '\n') {
462 size--;
463 buf++;
464 }
465 if (!size)
466 goto free_return;
467 buf++; size--;
468 if (0 <= it->entry_count) {
469 if (size < 20)
470 goto free_return;
471 hashcpy(it->sha1, (const unsigned char*)buf);
472 buf += 20;
473 size -= 20;
474 }
475#if DEBUG
477 if (0 <= it->entry_count)
478 fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n",
479 *buffer, it->entry_count, subtree_nr,
480 sha1_to_hex(it->sha1));
481 else
482 fprintf(stderr, "cache-tree <%s> (%d subtrees) invalid\n",
483 *buffer, subtree_nr);
484#endif
485 /*
487 * Just a heuristic -- we do not add directories that often but
488 * we do not want to have to extend it immediately when we do,
489 * hence +2.
490 */
491 it->subtree_alloc = subtree_nr + 2;
492 it->down = xcalloc(it->subtree_alloc, sizeof(struct cache_tree_sub *));
493 for (i = 0; i < subtree_nr; i++) {
494 /* read each subtree */
495 struct cache_tree *sub;
496 struct cache_tree_sub *subtree;
497 const char *name = buf;
498 sub = read_one(&buf, &size);
500 if (!sub)
501 goto free_return;
502 subtree = cache_tree_sub(it, name);
503 subtree->cache_tree = sub;
504 }
505 if (subtree_nr != it->subtree_nr)
506 die("cache-tree: internal error");
507 *buffer = buf;
508 *size_p = size;
509 return it;
510 free_return:
512 cache_tree_free(&it);
513 return NULL;
514}
515struct cache_tree *cache_tree_read(const char *buffer, unsigned long size)
517{
518 if (buffer[0])
519 return NULL; /* not the whole tree */
520 return read_one(&buffer, &size);
521}
522static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *path)
524{
525 if (!it)
526 return NULL;
527 while (*path) {
528 const char *slash;
529 struct cache_tree_sub *sub;
530 slash = strchr(path, '/');
532 if (!slash)
533 slash = path + strlen(path);
534 /* between path and slash is the name of the
535 * subtree to look for.
536 */
537 sub = find_subtree(it, path, slash - path, 0);
538 if (!sub)
539 return NULL;
540 it = sub->cache_tree;
541 if (slash)
542 while (*slash && *slash == '/')
543 slash++;
544 if (!slash || !*slash)
545 return it; /* prefix ended with slashes */
546 path = slash;
547 }
548 return it;
549}
550int write_cache_as_tree(unsigned char *sha1, int flags, const char *prefix)
552{
553 int entries, was_valid, newfd;
554 struct lock_file *lock_file;
555 /*
557 * We can't free this memory, it becomes part of a linked list
558 * parsed atexit()
559 */
560 lock_file = xcalloc(1, sizeof(struct lock_file));
561 newfd = hold_locked_index(lock_file, 1);
563 entries = read_cache();
565 if (entries < 0)
566 return WRITE_TREE_UNREADABLE_INDEX;
567 if (flags & WRITE_TREE_IGNORE_CACHE_TREE)
568 cache_tree_free(&(active_cache_tree));
569 if (!active_cache_tree)
571 active_cache_tree = cache_tree();
572 was_valid = cache_tree_fully_valid(active_cache_tree);
574 if (!was_valid) {
575 int missing_ok = flags & WRITE_TREE_MISSING_OK;
576 if (cache_tree_update(active_cache_tree,
578 active_cache, active_nr,
579 missing_ok, 0, 0) < 0)
580 return WRITE_TREE_UNMERGED_INDEX;
581 if (0 <= newfd) {
582 if (!write_cache(newfd, active_cache, active_nr) &&
583 !commit_lock_file(lock_file))
584 newfd = -1;
585 }
586 /* Not being able to write is fine -- we are only interested
587 * in updating the cache-tree part, and if the next caller
588 * ends up using the old index with unupdated cache-tree part
589 * it misses the work we did here, but that is just a
590 * performance penalty and not a big deal.
591 */
592 }
593 if (prefix) {
595 struct cache_tree *subtree =
596 cache_tree_find(active_cache_tree, prefix);
597 if (!subtree)
598 return WRITE_TREE_PREFIX_ERROR;
599 hashcpy(sha1, subtree->sha1);
600 }
601 else
602 hashcpy(sha1, active_cache_tree->sha1);
603 if (0 <= newfd)
605 rollback_lock_file(lock_file);
606 return 0;
608}
609static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
611{
612 struct tree_desc desc;
613 struct name_entry entry;
614 int cnt;
615 hashcpy(it->sha1, tree->object.sha1);
617 init_tree_desc(&desc, tree->buffer, tree->size);
618 cnt = 0;
619 while (tree_entry(&desc, &entry)) {
620 if (!S_ISDIR(entry.mode))
621 cnt++;
622 else {
623 struct cache_tree_sub *sub;
624 struct tree *subtree = lookup_tree(entry.sha1);
625 if (!subtree->object.parsed)
626 parse_tree(subtree);
627 sub = cache_tree_sub(it, entry.path);
628 sub->cache_tree = cache_tree();
629 prime_cache_tree_rec(sub->cache_tree, subtree);
630 cnt += sub->cache_tree->entry_count;
631 }
632 }
633 it->entry_count = cnt;
634}
635void prime_cache_tree(struct cache_tree **it, struct tree *tree)
637{
638 cache_tree_free(it);
639 *it = cache_tree();
640 prime_cache_tree_rec(*it, tree);
641}
642/*
644 * find the cache_tree that corresponds to the current level without
645 * exploding the full path into textual form. The root of the
646 * cache tree is given as "root", and our current level is "info".
647 * (1) When at root level, info->prev is NULL, so it is "root" itself.
648 * (2) Otherwise, find the cache_tree that corresponds to one level
649 * above us, and find ourselves in there.
650 */
651static struct cache_tree *find_cache_tree_from_traversal(struct cache_tree *root,
652 struct traverse_info *info)
653{
654 struct cache_tree *our_parent;
655 if (!info->prev)
657 return root;
658 our_parent = find_cache_tree_from_traversal(root, info->prev);
659 return cache_tree_find(our_parent, info->name.path);
660}
661int cache_tree_matches_traversal(struct cache_tree *root,
663 struct name_entry *ent,
664 struct traverse_info *info)
665{
666 struct cache_tree *it;
667 it = find_cache_tree_from_traversal(root, info);
669 it = cache_tree_find(it, ent->path);
670 if (it && it->entry_count > 0 && !hashcmp(ent->sha1, it->sha1))
671 return it->entry_count;
672 return 0;
673}
674int update_main_cache_tree (int silent)
676{
677 if (!the_index.cache_tree)
678 the_index.cache_tree = cache_tree();
679 return cache_tree_update(the_index.cache_tree,
680 the_index.cache, the_index.cache_nr, 0, 0, silent);
681}