Merge branch 'js/smart-http-detect-remote-error'
[git] / cache-tree.c
1 #include "cache.h"
2 #include "lockfile.h"
3 #include "tree.h"
4 #include "tree-walk.h"
5 #include "cache-tree.h"
6 #include "object-store.h"
7 #include "replace-object.h"
8
9 #ifndef DEBUG
10 #define DEBUG 0
11 #endif
12
13 struct cache_tree *cache_tree(void)
14 {
15         struct cache_tree *it = xcalloc(1, sizeof(struct cache_tree));
16         it->entry_count = -1;
17         return it;
18 }
19
20 void cache_tree_free(struct cache_tree **it_p)
21 {
22         int i;
23         struct cache_tree *it = *it_p;
24
25         if (!it)
26                 return;
27         for (i = 0; i < it->subtree_nr; i++)
28                 if (it->down[i]) {
29                         cache_tree_free(&it->down[i]->cache_tree);
30                         free(it->down[i]);
31                 }
32         free(it->down);
33         free(it);
34         *it_p = NULL;
35 }
36
37 static int subtree_name_cmp(const char *one, int onelen,
38                             const char *two, int twolen)
39 {
40         if (onelen < twolen)
41                 return -1;
42         if (twolen < onelen)
43                 return 1;
44         return memcmp(one, two, onelen);
45 }
46
47 static int subtree_pos(struct cache_tree *it, const char *path, int pathlen)
48 {
49         struct cache_tree_sub **down = it->down;
50         int lo, hi;
51         lo = 0;
52         hi = it->subtree_nr;
53         while (lo < hi) {
54                 int mi = lo + (hi - lo) / 2;
55                 struct cache_tree_sub *mdl = down[mi];
56                 int cmp = subtree_name_cmp(path, pathlen,
57                                            mdl->name, mdl->namelen);
58                 if (!cmp)
59                         return mi;
60                 if (cmp < 0)
61                         hi = mi;
62                 else
63                         lo = mi + 1;
64         }
65         return -lo-1;
66 }
67
68 static struct cache_tree_sub *find_subtree(struct cache_tree *it,
69                                            const char *path,
70                                            int pathlen,
71                                            int create)
72 {
73         struct cache_tree_sub *down;
74         int pos = subtree_pos(it, path, pathlen);
75         if (0 <= pos)
76                 return it->down[pos];
77         if (!create)
78                 return NULL;
79
80         pos = -pos-1;
81         ALLOC_GROW(it->down, it->subtree_nr + 1, it->subtree_alloc);
82         it->subtree_nr++;
83
84         FLEX_ALLOC_MEM(down, name, path, pathlen);
85         down->cache_tree = NULL;
86         down->namelen = pathlen;
87
88         if (pos < it->subtree_nr)
89                 MOVE_ARRAY(it->down + pos + 1, it->down + pos,
90                            it->subtree_nr - pos - 1);
91         it->down[pos] = down;
92         return down;
93 }
94
95 struct cache_tree_sub *cache_tree_sub(struct cache_tree *it, const char *path)
96 {
97         int pathlen = strlen(path);
98         return find_subtree(it, path, pathlen, 1);
99 }
100
101 static int do_invalidate_path(struct cache_tree *it, const char *path)
102 {
103         /* a/b/c
104          * ==> invalidate self
105          * ==> find "a", have it invalidate "b/c"
106          * a
107          * ==> invalidate self
108          * ==> if "a" exists as a subtree, remove it.
109          */
110         const char *slash;
111         int namelen;
112         struct cache_tree_sub *down;
113
114 #if DEBUG
115         fprintf(stderr, "cache-tree invalidate <%s>\n", path);
116 #endif
117
118         if (!it)
119                 return 0;
120         slash = strchrnul(path, '/');
121         namelen = slash - path;
122         it->entry_count = -1;
123         if (!*slash) {
124                 int pos;
125                 pos = subtree_pos(it, path, namelen);
126                 if (0 <= pos) {
127                         cache_tree_free(&it->down[pos]->cache_tree);
128                         free(it->down[pos]);
129                         /* 0 1 2 3 4 5
130                          *       ^     ^subtree_nr = 6
131                          *       pos
132                          * move 4 and 5 up one place (2 entries)
133                          * 2 = 6 - 3 - 1 = subtree_nr - pos - 1
134                          */
135                         MOVE_ARRAY(it->down + pos, it->down + pos + 1,
136                                    it->subtree_nr - pos - 1);
137                         it->subtree_nr--;
138                 }
139                 return 1;
140         }
141         down = find_subtree(it, path, namelen, 0);
142         if (down)
143                 do_invalidate_path(down->cache_tree, slash + 1);
144         return 1;
145 }
146
147 void cache_tree_invalidate_path(struct index_state *istate, const char *path)
148 {
149         if (do_invalidate_path(istate->cache_tree, path))
150                 istate->cache_changed |= CACHE_TREE_CHANGED;
151 }
152
153 static int verify_cache(struct cache_entry **cache,
154                         int entries, int flags)
155 {
156         int i, funny;
157         int silent = flags & WRITE_TREE_SILENT;
158
159         /* Verify that the tree is merged */
160         funny = 0;
161         for (i = 0; i < entries; i++) {
162                 const struct cache_entry *ce = cache[i];
163                 if (ce_stage(ce)) {
164                         if (silent)
165                                 return -1;
166                         if (10 < ++funny) {
167                                 fprintf(stderr, "...\n");
168                                 break;
169                         }
170                         fprintf(stderr, "%s: unmerged (%s)\n",
171                                 ce->name, oid_to_hex(&ce->oid));
172                 }
173         }
174         if (funny)
175                 return -1;
176
177         /* Also verify that the cache does not have path and path/file
178          * at the same time.  At this point we know the cache has only
179          * stage 0 entries.
180          */
181         funny = 0;
182         for (i = 0; i < entries - 1; i++) {
183                 /* path/file always comes after path because of the way
184                  * the cache is sorted.  Also path can appear only once,
185                  * which means conflicting one would immediately follow.
186                  */
187                 const char *this_name = cache[i]->name;
188                 const char *next_name = cache[i+1]->name;
189                 int this_len = strlen(this_name);
190                 if (this_len < strlen(next_name) &&
191                     strncmp(this_name, next_name, this_len) == 0 &&
192                     next_name[this_len] == '/') {
193                         if (10 < ++funny) {
194                                 fprintf(stderr, "...\n");
195                                 break;
196                         }
197                         fprintf(stderr, "You have both %s and %s\n",
198                                 this_name, next_name);
199                 }
200         }
201         if (funny)
202                 return -1;
203         return 0;
204 }
205
206 static void discard_unused_subtrees(struct cache_tree *it)
207 {
208         struct cache_tree_sub **down = it->down;
209         int nr = it->subtree_nr;
210         int dst, src;
211         for (dst = src = 0; src < nr; src++) {
212                 struct cache_tree_sub *s = down[src];
213                 if (s->used)
214                         down[dst++] = s;
215                 else {
216                         cache_tree_free(&s->cache_tree);
217                         free(s);
218                         it->subtree_nr--;
219                 }
220         }
221 }
222
223 int cache_tree_fully_valid(struct cache_tree *it)
224 {
225         int i;
226         if (!it)
227                 return 0;
228         if (it->entry_count < 0 || !has_object_file(&it->oid))
229                 return 0;
230         for (i = 0; i < it->subtree_nr; i++) {
231                 if (!cache_tree_fully_valid(it->down[i]->cache_tree))
232                         return 0;
233         }
234         return 1;
235 }
236
237 static int update_one(struct cache_tree *it,
238                       struct cache_entry **cache,
239                       int entries,
240                       const char *base,
241                       int baselen,
242                       int *skip_count,
243                       int flags)
244 {
245         struct strbuf buffer;
246         int missing_ok = flags & WRITE_TREE_MISSING_OK;
247         int dryrun = flags & WRITE_TREE_DRY_RUN;
248         int repair = flags & WRITE_TREE_REPAIR;
249         int to_invalidate = 0;
250         int i;
251
252         assert(!(dryrun && repair));
253
254         *skip_count = 0;
255
256         if (0 <= it->entry_count && has_object_file(&it->oid))
257                 return it->entry_count;
258
259         /*
260          * We first scan for subtrees and update them; we start by
261          * marking existing subtrees -- the ones that are unmarked
262          * should not be in the result.
263          */
264         for (i = 0; i < it->subtree_nr; i++)
265                 it->down[i]->used = 0;
266
267         /*
268          * Find the subtrees and update them.
269          */
270         i = 0;
271         while (i < entries) {
272                 const struct cache_entry *ce = cache[i];
273                 struct cache_tree_sub *sub;
274                 const char *path, *slash;
275                 int pathlen, sublen, subcnt, subskip;
276
277                 path = ce->name;
278                 pathlen = ce_namelen(ce);
279                 if (pathlen <= baselen || memcmp(base, path, baselen))
280                         break; /* at the end of this level */
281
282                 slash = strchr(path + baselen, '/');
283                 if (!slash) {
284                         i++;
285                         continue;
286                 }
287                 /*
288                  * a/bbb/c (base = a/, slash = /c)
289                  * ==>
290                  * path+baselen = bbb/c, sublen = 3
291                  */
292                 sublen = slash - (path + baselen);
293                 sub = find_subtree(it, path + baselen, sublen, 1);
294                 if (!sub->cache_tree)
295                         sub->cache_tree = cache_tree();
296                 subcnt = update_one(sub->cache_tree,
297                                     cache + i, entries - i,
298                                     path,
299                                     baselen + sublen + 1,
300                                     &subskip,
301                                     flags);
302                 if (subcnt < 0)
303                         return subcnt;
304                 if (!subcnt)
305                         die("index cache-tree records empty sub-tree");
306                 i += subcnt;
307                 sub->count = subcnt; /* to be used in the next loop */
308                 *skip_count += subskip;
309                 sub->used = 1;
310         }
311
312         discard_unused_subtrees(it);
313
314         /*
315          * Then write out the tree object for this level.
316          */
317         strbuf_init(&buffer, 8192);
318
319         i = 0;
320         while (i < entries) {
321                 const struct cache_entry *ce = cache[i];
322                 struct cache_tree_sub *sub = NULL;
323                 const char *path, *slash;
324                 int pathlen, entlen;
325                 const struct object_id *oid;
326                 unsigned mode;
327                 int expected_missing = 0;
328                 int contains_ita = 0;
329                 int ce_missing_ok;
330
331                 path = ce->name;
332                 pathlen = ce_namelen(ce);
333                 if (pathlen <= baselen || memcmp(base, path, baselen))
334                         break; /* at the end of this level */
335
336                 slash = strchr(path + baselen, '/');
337                 if (slash) {
338                         entlen = slash - (path + baselen);
339                         sub = find_subtree(it, path + baselen, entlen, 0);
340                         if (!sub)
341                                 die("cache-tree.c: '%.*s' in '%s' not found",
342                                     entlen, path + baselen, path);
343                         i += sub->count;
344                         oid = &sub->cache_tree->oid;
345                         mode = S_IFDIR;
346                         contains_ita = sub->cache_tree->entry_count < 0;
347                         if (contains_ita) {
348                                 to_invalidate = 1;
349                                 expected_missing = 1;
350                         }
351                 }
352                 else {
353                         oid = &ce->oid;
354                         mode = ce->ce_mode;
355                         entlen = pathlen - baselen;
356                         i++;
357                 }
358
359                 ce_missing_ok = mode == S_IFGITLINK || missing_ok ||
360                         (repository_format_partial_clone &&
361                          ce_skip_worktree(ce));
362                 if (is_null_oid(oid) ||
363                     (!ce_missing_ok && !has_object_file(oid))) {
364                         strbuf_release(&buffer);
365                         if (expected_missing)
366                                 return -1;
367                         return error("invalid object %06o %s for '%.*s'",
368                                 mode, oid_to_hex(oid), entlen+baselen, path);
369                 }
370
371                 /*
372                  * CE_REMOVE entries are removed before the index is
373                  * written to disk. Skip them to remain consistent
374                  * with the future on-disk index.
375                  */
376                 if (ce->ce_flags & CE_REMOVE) {
377                         *skip_count = *skip_count + 1;
378                         continue;
379                 }
380
381                 /*
382                  * CE_INTENT_TO_ADD entries exist on on-disk index but
383                  * they are not part of generated trees. Invalidate up
384                  * to root to force cache-tree users to read elsewhere.
385                  */
386                 if (!sub && ce_intent_to_add(ce)) {
387                         to_invalidate = 1;
388                         continue;
389                 }
390
391                 /*
392                  * "sub" can be an empty tree if all subentries are i-t-a.
393                  */
394                 if (contains_ita && is_empty_tree_oid(oid))
395                         continue;
396
397                 strbuf_grow(&buffer, entlen + 100);
398                 strbuf_addf(&buffer, "%o %.*s%c", mode, entlen, path + baselen, '\0');
399                 strbuf_add(&buffer, oid->hash, the_hash_algo->rawsz);
400
401 #if DEBUG
402                 fprintf(stderr, "cache-tree update-one %o %.*s\n",
403                         mode, entlen, path + baselen);
404 #endif
405         }
406
407         if (repair) {
408                 struct object_id oid;
409                 hash_object_file(buffer.buf, buffer.len, tree_type, &oid);
410                 if (has_object_file(&oid))
411                         oidcpy(&it->oid, &oid);
412                 else
413                         to_invalidate = 1;
414         } else if (dryrun) {
415                 hash_object_file(buffer.buf, buffer.len, tree_type, &it->oid);
416         } else if (write_object_file(buffer.buf, buffer.len, tree_type,
417                                      &it->oid)) {
418                 strbuf_release(&buffer);
419                 return -1;
420         }
421
422         strbuf_release(&buffer);
423         it->entry_count = to_invalidate ? -1 : i - *skip_count;
424 #if DEBUG
425         fprintf(stderr, "cache-tree update-one (%d ent, %d subtree) %s\n",
426                 it->entry_count, it->subtree_nr,
427                 oid_to_hex(&it->oid));
428 #endif
429         return i;
430 }
431
432 int cache_tree_update(struct index_state *istate, int flags)
433 {
434         struct cache_tree *it = istate->cache_tree;
435         struct cache_entry **cache = istate->cache;
436         int entries = istate->cache_nr;
437         int skip, i = verify_cache(cache, entries, flags);
438
439         if (i)
440                 return i;
441         trace_performance_enter();
442         i = update_one(it, cache, entries, "", 0, &skip, flags);
443         trace_performance_leave("cache_tree_update");
444         if (i < 0)
445                 return i;
446         istate->cache_changed |= CACHE_TREE_CHANGED;
447         return 0;
448 }
449
450 static void write_one(struct strbuf *buffer, struct cache_tree *it,
451                       const char *path, int pathlen)
452 {
453         int i;
454
455         /* One "cache-tree" entry consists of the following:
456          * path (NUL terminated)
457          * entry_count, subtree_nr ("%d %d\n")
458          * tree-sha1 (missing if invalid)
459          * subtree_nr "cache-tree" entries for subtrees.
460          */
461         strbuf_grow(buffer, pathlen + 100);
462         strbuf_add(buffer, path, pathlen);
463         strbuf_addf(buffer, "%c%d %d\n", 0, it->entry_count, it->subtree_nr);
464
465 #if DEBUG
466         if (0 <= it->entry_count)
467                 fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n",
468                         pathlen, path, it->entry_count, it->subtree_nr,
469                         oid_to_hex(&it->oid));
470         else
471                 fprintf(stderr, "cache-tree <%.*s> (%d subtree) invalid\n",
472                         pathlen, path, it->subtree_nr);
473 #endif
474
475         if (0 <= it->entry_count) {
476                 strbuf_add(buffer, it->oid.hash, the_hash_algo->rawsz);
477         }
478         for (i = 0; i < it->subtree_nr; i++) {
479                 struct cache_tree_sub *down = it->down[i];
480                 if (i) {
481                         struct cache_tree_sub *prev = it->down[i-1];
482                         if (subtree_name_cmp(down->name, down->namelen,
483                                              prev->name, prev->namelen) <= 0)
484                                 die("fatal - unsorted cache subtree");
485                 }
486                 write_one(buffer, down->cache_tree, down->name, down->namelen);
487         }
488 }
489
490 void cache_tree_write(struct strbuf *sb, struct cache_tree *root)
491 {
492         write_one(sb, root, "", 0);
493 }
494
495 static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
496 {
497         const char *buf = *buffer;
498         unsigned long size = *size_p;
499         const char *cp;
500         char *ep;
501         struct cache_tree *it;
502         int i, subtree_nr;
503         const unsigned rawsz = the_hash_algo->rawsz;
504
505         it = NULL;
506         /* skip name, but make sure name exists */
507         while (size && *buf) {
508                 size--;
509                 buf++;
510         }
511         if (!size)
512                 goto free_return;
513         buf++; size--;
514         it = cache_tree();
515
516         cp = buf;
517         it->entry_count = strtol(cp, &ep, 10);
518         if (cp == ep)
519                 goto free_return;
520         cp = ep;
521         subtree_nr = strtol(cp, &ep, 10);
522         if (cp == ep)
523                 goto free_return;
524         while (size && *buf && *buf != '\n') {
525                 size--;
526                 buf++;
527         }
528         if (!size)
529                 goto free_return;
530         buf++; size--;
531         if (0 <= it->entry_count) {
532                 if (size < rawsz)
533                         goto free_return;
534                 oidread(&it->oid, (const unsigned char *)buf);
535                 buf += rawsz;
536                 size -= rawsz;
537         }
538
539 #if DEBUG
540         if (0 <= it->entry_count)
541                 fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n",
542                         *buffer, it->entry_count, subtree_nr,
543                         oid_to_hex(&it->oid));
544         else
545                 fprintf(stderr, "cache-tree <%s> (%d subtrees) invalid\n",
546                         *buffer, subtree_nr);
547 #endif
548
549         /*
550          * Just a heuristic -- we do not add directories that often but
551          * we do not want to have to extend it immediately when we do,
552          * hence +2.
553          */
554         it->subtree_alloc = subtree_nr + 2;
555         it->down = xcalloc(it->subtree_alloc, sizeof(struct cache_tree_sub *));
556         for (i = 0; i < subtree_nr; i++) {
557                 /* read each subtree */
558                 struct cache_tree *sub;
559                 struct cache_tree_sub *subtree;
560                 const char *name = buf;
561
562                 sub = read_one(&buf, &size);
563                 if (!sub)
564                         goto free_return;
565                 subtree = cache_tree_sub(it, name);
566                 subtree->cache_tree = sub;
567         }
568         if (subtree_nr != it->subtree_nr)
569                 die("cache-tree: internal error");
570         *buffer = buf;
571         *size_p = size;
572         return it;
573
574  free_return:
575         cache_tree_free(&it);
576         return NULL;
577 }
578
579 struct cache_tree *cache_tree_read(const char *buffer, unsigned long size)
580 {
581         if (buffer[0])
582                 return NULL; /* not the whole tree */
583         return read_one(&buffer, &size);
584 }
585
586 static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *path)
587 {
588         if (!it)
589                 return NULL;
590         while (*path) {
591                 const char *slash;
592                 struct cache_tree_sub *sub;
593
594                 slash = strchrnul(path, '/');
595                 /*
596                  * Between path and slash is the name of the subtree
597                  * to look for.
598                  */
599                 sub = find_subtree(it, path, slash - path, 0);
600                 if (!sub)
601                         return NULL;
602                 it = sub->cache_tree;
603
604                 path = slash;
605                 while (*path == '/')
606                         path++;
607         }
608         return it;
609 }
610
611 int write_index_as_tree(struct object_id *oid, struct index_state *index_state, const char *index_path, int flags, const char *prefix)
612 {
613         int entries, was_valid;
614         struct lock_file lock_file = LOCK_INIT;
615         int ret = 0;
616
617         hold_lock_file_for_update(&lock_file, index_path, LOCK_DIE_ON_ERROR);
618
619         entries = read_index_from(index_state, index_path, get_git_dir());
620         if (entries < 0) {
621                 ret = WRITE_TREE_UNREADABLE_INDEX;
622                 goto out;
623         }
624         if (flags & WRITE_TREE_IGNORE_CACHE_TREE)
625                 cache_tree_free(&index_state->cache_tree);
626
627         if (!index_state->cache_tree)
628                 index_state->cache_tree = cache_tree();
629
630         was_valid = cache_tree_fully_valid(index_state->cache_tree);
631         if (!was_valid) {
632                 if (cache_tree_update(index_state, flags) < 0) {
633                         ret = WRITE_TREE_UNMERGED_INDEX;
634                         goto out;
635                 }
636                 write_locked_index(index_state, &lock_file, COMMIT_LOCK);
637                 /* Not being able to write is fine -- we are only interested
638                  * in updating the cache-tree part, and if the next caller
639                  * ends up using the old index with unupdated cache-tree part
640                  * it misses the work we did here, but that is just a
641                  * performance penalty and not a big deal.
642                  */
643         }
644
645         if (prefix) {
646                 struct cache_tree *subtree;
647                 subtree = cache_tree_find(index_state->cache_tree, prefix);
648                 if (!subtree) {
649                         ret = WRITE_TREE_PREFIX_ERROR;
650                         goto out;
651                 }
652                 oidcpy(oid, &subtree->oid);
653         }
654         else
655                 oidcpy(oid, &index_state->cache_tree->oid);
656
657 out:
658         rollback_lock_file(&lock_file);
659         return ret;
660 }
661
662 static void prime_cache_tree_rec(struct repository *r,
663                                  struct cache_tree *it,
664                                  struct tree *tree)
665 {
666         struct tree_desc desc;
667         struct name_entry entry;
668         int cnt;
669
670         oidcpy(&it->oid, &tree->object.oid);
671         init_tree_desc(&desc, tree->buffer, tree->size);
672         cnt = 0;
673         while (tree_entry(&desc, &entry)) {
674                 if (!S_ISDIR(entry.mode))
675                         cnt++;
676                 else {
677                         struct cache_tree_sub *sub;
678                         struct tree *subtree = lookup_tree(r, &entry.oid);
679                         if (!subtree->object.parsed)
680                                 parse_tree(subtree);
681                         sub = cache_tree_sub(it, entry.path);
682                         sub->cache_tree = cache_tree();
683                         prime_cache_tree_rec(r, sub->cache_tree, subtree);
684                         cnt += sub->cache_tree->entry_count;
685                 }
686         }
687         it->entry_count = cnt;
688 }
689
690 void prime_cache_tree(struct repository *r,
691                       struct index_state *istate,
692                       struct tree *tree)
693 {
694         cache_tree_free(&istate->cache_tree);
695         istate->cache_tree = cache_tree();
696         prime_cache_tree_rec(r, istate->cache_tree, tree);
697         istate->cache_changed |= CACHE_TREE_CHANGED;
698 }
699
700 /*
701  * find the cache_tree that corresponds to the current level without
702  * exploding the full path into textual form.  The root of the
703  * cache tree is given as "root", and our current level is "info".
704  * (1) When at root level, info->prev is NULL, so it is "root" itself.
705  * (2) Otherwise, find the cache_tree that corresponds to one level
706  *     above us, and find ourselves in there.
707  */
708 static struct cache_tree *find_cache_tree_from_traversal(struct cache_tree *root,
709                                                          struct traverse_info *info)
710 {
711         struct cache_tree *our_parent;
712
713         if (!info->prev)
714                 return root;
715         our_parent = find_cache_tree_from_traversal(root, info->prev);
716         return cache_tree_find(our_parent, info->name.path);
717 }
718
719 int cache_tree_matches_traversal(struct cache_tree *root,
720                                  struct name_entry *ent,
721                                  struct traverse_info *info)
722 {
723         struct cache_tree *it;
724
725         it = find_cache_tree_from_traversal(root, info);
726         it = cache_tree_find(it, ent->path);
727         if (it && it->entry_count > 0 && oideq(&ent->oid, &it->oid))
728                 return it->entry_count;
729         return 0;
730 }
731
732 static void verify_one(struct repository *r,
733                        struct index_state *istate,
734                        struct cache_tree *it,
735                        struct strbuf *path)
736 {
737         int i, pos, len = path->len;
738         struct strbuf tree_buf = STRBUF_INIT;
739         struct object_id new_oid;
740
741         for (i = 0; i < it->subtree_nr; i++) {
742                 strbuf_addf(path, "%s/", it->down[i]->name);
743                 verify_one(r, istate, it->down[i]->cache_tree, path);
744                 strbuf_setlen(path, len);
745         }
746
747         if (it->entry_count < 0 ||
748             /* no verification on tests (t7003) that replace trees */
749             lookup_replace_object(r, &it->oid) != &it->oid)
750                 return;
751
752         if (path->len) {
753                 pos = index_name_pos(istate, path->buf, path->len);
754                 pos = -pos - 1;
755         } else {
756                 pos = 0;
757         }
758
759         i = 0;
760         while (i < it->entry_count) {
761                 struct cache_entry *ce = istate->cache[pos + i];
762                 const char *slash;
763                 struct cache_tree_sub *sub = NULL;
764                 const struct object_id *oid;
765                 const char *name;
766                 unsigned mode;
767                 int entlen;
768
769                 if (ce->ce_flags & (CE_STAGEMASK | CE_INTENT_TO_ADD | CE_REMOVE))
770                         BUG("%s with flags 0x%x should not be in cache-tree",
771                             ce->name, ce->ce_flags);
772                 name = ce->name + path->len;
773                 slash = strchr(name, '/');
774                 if (slash) {
775                         entlen = slash - name;
776                         sub = find_subtree(it, ce->name + path->len, entlen, 0);
777                         if (!sub || sub->cache_tree->entry_count < 0)
778                                 BUG("bad subtree '%.*s'", entlen, name);
779                         oid = &sub->cache_tree->oid;
780                         mode = S_IFDIR;
781                         i += sub->cache_tree->entry_count;
782                 } else {
783                         oid = &ce->oid;
784                         mode = ce->ce_mode;
785                         entlen = ce_namelen(ce) - path->len;
786                         i++;
787                 }
788                 strbuf_addf(&tree_buf, "%o %.*s%c", mode, entlen, name, '\0');
789                 strbuf_add(&tree_buf, oid->hash, the_hash_algo->rawsz);
790         }
791         hash_object_file(tree_buf.buf, tree_buf.len, tree_type, &new_oid);
792         if (!oideq(&new_oid, &it->oid))
793                 BUG("cache-tree for path %.*s does not match. "
794                     "Expected %s got %s", len, path->buf,
795                     oid_to_hex(&new_oid), oid_to_hex(&it->oid));
796         strbuf_setlen(path, len);
797         strbuf_release(&tree_buf);
798 }
799
800 void cache_tree_verify(struct repository *r, struct index_state *istate)
801 {
802         struct strbuf path = STRBUF_INIT;
803
804         if (!istate->cache_tree)
805                 return;
806         verify_one(r, istate, istate->cache_tree, &path);
807         strbuf_release(&path);
808 }