Merge branch 'en/rerere-multi-stage-1-fix'
[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_sha1_file(it->oid.hash))
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_sha1_file(it->oid.hash))
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
330                 path = ce->name;
331                 pathlen = ce_namelen(ce);
332                 if (pathlen <= baselen || memcmp(base, path, baselen))
333                         break; /* at the end of this level */
334
335                 slash = strchr(path + baselen, '/');
336                 if (slash) {
337                         entlen = slash - (path + baselen);
338                         sub = find_subtree(it, path + baselen, entlen, 0);
339                         if (!sub)
340                                 die("cache-tree.c: '%.*s' in '%s' not found",
341                                     entlen, path + baselen, path);
342                         i += sub->count;
343                         oid = &sub->cache_tree->oid;
344                         mode = S_IFDIR;
345                         contains_ita = sub->cache_tree->entry_count < 0;
346                         if (contains_ita) {
347                                 to_invalidate = 1;
348                                 expected_missing = 1;
349                         }
350                 }
351                 else {
352                         oid = &ce->oid;
353                         mode = ce->ce_mode;
354                         entlen = pathlen - baselen;
355                         i++;
356                 }
357
358                 if (is_null_oid(oid) ||
359                     (mode != S_IFGITLINK && !missing_ok && !has_object_file(oid))) {
360                         strbuf_release(&buffer);
361                         if (expected_missing)
362                                 return -1;
363                         return error("invalid object %06o %s for '%.*s'",
364                                 mode, oid_to_hex(oid), entlen+baselen, path);
365                 }
366
367                 /*
368                  * CE_REMOVE entries are removed before the index is
369                  * written to disk. Skip them to remain consistent
370                  * with the future on-disk index.
371                  */
372                 if (ce->ce_flags & CE_REMOVE) {
373                         *skip_count = *skip_count + 1;
374                         continue;
375                 }
376
377                 /*
378                  * CE_INTENT_TO_ADD entries exist on on-disk index but
379                  * they are not part of generated trees. Invalidate up
380                  * to root to force cache-tree users to read elsewhere.
381                  */
382                 if (!sub && ce_intent_to_add(ce)) {
383                         to_invalidate = 1;
384                         continue;
385                 }
386
387                 /*
388                  * "sub" can be an empty tree if all subentries are i-t-a.
389                  */
390                 if (contains_ita && is_empty_tree_oid(oid))
391                         continue;
392
393                 strbuf_grow(&buffer, entlen + 100);
394                 strbuf_addf(&buffer, "%o %.*s%c", mode, entlen, path + baselen, '\0');
395                 strbuf_add(&buffer, oid->hash, the_hash_algo->rawsz);
396
397 #if DEBUG
398                 fprintf(stderr, "cache-tree update-one %o %.*s\n",
399                         mode, entlen, path + baselen);
400 #endif
401         }
402
403         if (repair) {
404                 struct object_id oid;
405                 hash_object_file(buffer.buf, buffer.len, tree_type, &oid);
406                 if (has_object_file(&oid))
407                         oidcpy(&it->oid, &oid);
408                 else
409                         to_invalidate = 1;
410         } else if (dryrun) {
411                 hash_object_file(buffer.buf, buffer.len, tree_type, &it->oid);
412         } else if (write_object_file(buffer.buf, buffer.len, tree_type,
413                                      &it->oid)) {
414                 strbuf_release(&buffer);
415                 return -1;
416         }
417
418         strbuf_release(&buffer);
419         it->entry_count = to_invalidate ? -1 : i - *skip_count;
420 #if DEBUG
421         fprintf(stderr, "cache-tree update-one (%d ent, %d subtree) %s\n",
422                 it->entry_count, it->subtree_nr,
423                 oid_to_hex(&it->oid));
424 #endif
425         return i;
426 }
427
428 int cache_tree_update(struct index_state *istate, int flags)
429 {
430         struct cache_tree *it = istate->cache_tree;
431         struct cache_entry **cache = istate->cache;
432         int entries = istate->cache_nr;
433         int skip, i = verify_cache(cache, entries, flags);
434
435         if (i)
436                 return i;
437         trace_performance_enter();
438         i = update_one(it, cache, entries, "", 0, &skip, flags);
439         trace_performance_leave("cache_tree_update");
440         if (i < 0)
441                 return i;
442         istate->cache_changed |= CACHE_TREE_CHANGED;
443         return 0;
444 }
445
446 static void write_one(struct strbuf *buffer, struct cache_tree *it,
447                       const char *path, int pathlen)
448 {
449         int i;
450
451         /* One "cache-tree" entry consists of the following:
452          * path (NUL terminated)
453          * entry_count, subtree_nr ("%d %d\n")
454          * tree-sha1 (missing if invalid)
455          * subtree_nr "cache-tree" entries for subtrees.
456          */
457         strbuf_grow(buffer, pathlen + 100);
458         strbuf_add(buffer, path, pathlen);
459         strbuf_addf(buffer, "%c%d %d\n", 0, it->entry_count, it->subtree_nr);
460
461 #if DEBUG
462         if (0 <= it->entry_count)
463                 fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n",
464                         pathlen, path, it->entry_count, it->subtree_nr,
465                         oid_to_hex(&it->oid));
466         else
467                 fprintf(stderr, "cache-tree <%.*s> (%d subtree) invalid\n",
468                         pathlen, path, it->subtree_nr);
469 #endif
470
471         if (0 <= it->entry_count) {
472                 strbuf_add(buffer, it->oid.hash, the_hash_algo->rawsz);
473         }
474         for (i = 0; i < it->subtree_nr; i++) {
475                 struct cache_tree_sub *down = it->down[i];
476                 if (i) {
477                         struct cache_tree_sub *prev = it->down[i-1];
478                         if (subtree_name_cmp(down->name, down->namelen,
479                                              prev->name, prev->namelen) <= 0)
480                                 die("fatal - unsorted cache subtree");
481                 }
482                 write_one(buffer, down->cache_tree, down->name, down->namelen);
483         }
484 }
485
486 void cache_tree_write(struct strbuf *sb, struct cache_tree *root)
487 {
488         write_one(sb, root, "", 0);
489 }
490
491 static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
492 {
493         const char *buf = *buffer;
494         unsigned long size = *size_p;
495         const char *cp;
496         char *ep;
497         struct cache_tree *it;
498         int i, subtree_nr;
499         const unsigned rawsz = the_hash_algo->rawsz;
500
501         it = NULL;
502         /* skip name, but make sure name exists */
503         while (size && *buf) {
504                 size--;
505                 buf++;
506         }
507         if (!size)
508                 goto free_return;
509         buf++; size--;
510         it = cache_tree();
511
512         cp = buf;
513         it->entry_count = strtol(cp, &ep, 10);
514         if (cp == ep)
515                 goto free_return;
516         cp = ep;
517         subtree_nr = strtol(cp, &ep, 10);
518         if (cp == ep)
519                 goto free_return;
520         while (size && *buf && *buf != '\n') {
521                 size--;
522                 buf++;
523         }
524         if (!size)
525                 goto free_return;
526         buf++; size--;
527         if (0 <= it->entry_count) {
528                 if (size < rawsz)
529                         goto free_return;
530                 oidread(&it->oid, (const unsigned char *)buf);
531                 buf += rawsz;
532                 size -= rawsz;
533         }
534
535 #if DEBUG
536         if (0 <= it->entry_count)
537                 fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n",
538                         *buffer, it->entry_count, subtree_nr,
539                         oid_to_hex(&it->oid));
540         else
541                 fprintf(stderr, "cache-tree <%s> (%d subtrees) invalid\n",
542                         *buffer, subtree_nr);
543 #endif
544
545         /*
546          * Just a heuristic -- we do not add directories that often but
547          * we do not want to have to extend it immediately when we do,
548          * hence +2.
549          */
550         it->subtree_alloc = subtree_nr + 2;
551         it->down = xcalloc(it->subtree_alloc, sizeof(struct cache_tree_sub *));
552         for (i = 0; i < subtree_nr; i++) {
553                 /* read each subtree */
554                 struct cache_tree *sub;
555                 struct cache_tree_sub *subtree;
556                 const char *name = buf;
557
558                 sub = read_one(&buf, &size);
559                 if (!sub)
560                         goto free_return;
561                 subtree = cache_tree_sub(it, name);
562                 subtree->cache_tree = sub;
563         }
564         if (subtree_nr != it->subtree_nr)
565                 die("cache-tree: internal error");
566         *buffer = buf;
567         *size_p = size;
568         return it;
569
570  free_return:
571         cache_tree_free(&it);
572         return NULL;
573 }
574
575 struct cache_tree *cache_tree_read(const char *buffer, unsigned long size)
576 {
577         if (buffer[0])
578                 return NULL; /* not the whole tree */
579         return read_one(&buffer, &size);
580 }
581
582 static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *path)
583 {
584         if (!it)
585                 return NULL;
586         while (*path) {
587                 const char *slash;
588                 struct cache_tree_sub *sub;
589
590                 slash = strchrnul(path, '/');
591                 /*
592                  * Between path and slash is the name of the subtree
593                  * to look for.
594                  */
595                 sub = find_subtree(it, path, slash - path, 0);
596                 if (!sub)
597                         return NULL;
598                 it = sub->cache_tree;
599
600                 path = slash;
601                 while (*path == '/')
602                         path++;
603         }
604         return it;
605 }
606
607 int write_index_as_tree(struct object_id *oid, struct index_state *index_state, const char *index_path, int flags, const char *prefix)
608 {
609         int entries, was_valid;
610         struct lock_file lock_file = LOCK_INIT;
611         int ret = 0;
612
613         hold_lock_file_for_update(&lock_file, index_path, LOCK_DIE_ON_ERROR);
614
615         entries = read_index_from(index_state, index_path, get_git_dir());
616         if (entries < 0) {
617                 ret = WRITE_TREE_UNREADABLE_INDEX;
618                 goto out;
619         }
620         if (flags & WRITE_TREE_IGNORE_CACHE_TREE)
621                 cache_tree_free(&index_state->cache_tree);
622
623         if (!index_state->cache_tree)
624                 index_state->cache_tree = cache_tree();
625
626         was_valid = cache_tree_fully_valid(index_state->cache_tree);
627         if (!was_valid) {
628                 if (cache_tree_update(index_state, flags) < 0) {
629                         ret = WRITE_TREE_UNMERGED_INDEX;
630                         goto out;
631                 }
632                 write_locked_index(index_state, &lock_file, COMMIT_LOCK);
633                 /* Not being able to write is fine -- we are only interested
634                  * in updating the cache-tree part, and if the next caller
635                  * ends up using the old index with unupdated cache-tree part
636                  * it misses the work we did here, but that is just a
637                  * performance penalty and not a big deal.
638                  */
639         }
640
641         if (prefix) {
642                 struct cache_tree *subtree;
643                 subtree = cache_tree_find(index_state->cache_tree, prefix);
644                 if (!subtree) {
645                         ret = WRITE_TREE_PREFIX_ERROR;
646                         goto out;
647                 }
648                 oidcpy(oid, &subtree->oid);
649         }
650         else
651                 oidcpy(oid, &index_state->cache_tree->oid);
652
653 out:
654         rollback_lock_file(&lock_file);
655         return ret;
656 }
657
658 static void prime_cache_tree_rec(struct cache_tree *it, struct tree *tree)
659 {
660         struct tree_desc desc;
661         struct name_entry entry;
662         int cnt;
663
664         oidcpy(&it->oid, &tree->object.oid);
665         init_tree_desc(&desc, tree->buffer, tree->size);
666         cnt = 0;
667         while (tree_entry(&desc, &entry)) {
668                 if (!S_ISDIR(entry.mode))
669                         cnt++;
670                 else {
671                         struct cache_tree_sub *sub;
672                         struct tree *subtree = lookup_tree(the_repository,
673                                                            entry.oid);
674                         if (!subtree->object.parsed)
675                                 parse_tree(subtree);
676                         sub = cache_tree_sub(it, entry.path);
677                         sub->cache_tree = cache_tree();
678                         prime_cache_tree_rec(sub->cache_tree, subtree);
679                         cnt += sub->cache_tree->entry_count;
680                 }
681         }
682         it->entry_count = cnt;
683 }
684
685 void prime_cache_tree(struct index_state *istate, struct tree *tree)
686 {
687         cache_tree_free(&istate->cache_tree);
688         istate->cache_tree = cache_tree();
689         prime_cache_tree_rec(istate->cache_tree, tree);
690         istate->cache_changed |= CACHE_TREE_CHANGED;
691 }
692
693 /*
694  * find the cache_tree that corresponds to the current level without
695  * exploding the full path into textual form.  The root of the
696  * cache tree is given as "root", and our current level is "info".
697  * (1) When at root level, info->prev is NULL, so it is "root" itself.
698  * (2) Otherwise, find the cache_tree that corresponds to one level
699  *     above us, and find ourselves in there.
700  */
701 static struct cache_tree *find_cache_tree_from_traversal(struct cache_tree *root,
702                                                          struct traverse_info *info)
703 {
704         struct cache_tree *our_parent;
705
706         if (!info->prev)
707                 return root;
708         our_parent = find_cache_tree_from_traversal(root, info->prev);
709         return cache_tree_find(our_parent, info->name.path);
710 }
711
712 int cache_tree_matches_traversal(struct cache_tree *root,
713                                  struct name_entry *ent,
714                                  struct traverse_info *info)
715 {
716         struct cache_tree *it;
717
718         it = find_cache_tree_from_traversal(root, info);
719         it = cache_tree_find(it, ent->path);
720         if (it && it->entry_count > 0 && oideq(ent->oid, &it->oid))
721                 return it->entry_count;
722         return 0;
723 }
724
725 static void verify_one(struct index_state *istate,
726                        struct cache_tree *it,
727                        struct strbuf *path)
728 {
729         int i, pos, len = path->len;
730         struct strbuf tree_buf = STRBUF_INIT;
731         struct object_id new_oid;
732
733         for (i = 0; i < it->subtree_nr; i++) {
734                 strbuf_addf(path, "%s/", it->down[i]->name);
735                 verify_one(istate, it->down[i]->cache_tree, path);
736                 strbuf_setlen(path, len);
737         }
738
739         if (it->entry_count < 0 ||
740             /* no verification on tests (t7003) that replace trees */
741             lookup_replace_object(the_repository, &it->oid) != &it->oid)
742                 return;
743
744         if (path->len) {
745                 pos = index_name_pos(istate, path->buf, path->len);
746                 pos = -pos - 1;
747         } else {
748                 pos = 0;
749         }
750
751         i = 0;
752         while (i < it->entry_count) {
753                 struct cache_entry *ce = istate->cache[pos + i];
754                 const char *slash;
755                 struct cache_tree_sub *sub = NULL;
756                 const struct object_id *oid;
757                 const char *name;
758                 unsigned mode;
759                 int entlen;
760
761                 if (ce->ce_flags & (CE_STAGEMASK | CE_INTENT_TO_ADD | CE_REMOVE))
762                         BUG("%s with flags 0x%x should not be in cache-tree",
763                             ce->name, ce->ce_flags);
764                 name = ce->name + path->len;
765                 slash = strchr(name, '/');
766                 if (slash) {
767                         entlen = slash - name;
768                         sub = find_subtree(it, ce->name + path->len, entlen, 0);
769                         if (!sub || sub->cache_tree->entry_count < 0)
770                                 BUG("bad subtree '%.*s'", entlen, name);
771                         oid = &sub->cache_tree->oid;
772                         mode = S_IFDIR;
773                         i += sub->cache_tree->entry_count;
774                 } else {
775                         oid = &ce->oid;
776                         mode = ce->ce_mode;
777                         entlen = ce_namelen(ce) - path->len;
778                         i++;
779                 }
780                 strbuf_addf(&tree_buf, "%o %.*s%c", mode, entlen, name, '\0');
781                 strbuf_add(&tree_buf, oid->hash, the_hash_algo->rawsz);
782         }
783         hash_object_file(tree_buf.buf, tree_buf.len, tree_type, &new_oid);
784         if (oidcmp(&new_oid, &it->oid))
785                 BUG("cache-tree for path %.*s does not match. "
786                     "Expected %s got %s", len, path->buf,
787                     oid_to_hex(&new_oid), oid_to_hex(&it->oid));
788         strbuf_setlen(path, len);
789         strbuf_release(&tree_buf);
790 }
791
792 void cache_tree_verify(struct index_state *istate)
793 {
794         struct strbuf path = STRBUF_INIT;
795
796         if (!istate->cache_tree)
797                 return;
798         verify_one(istate, istate->cache_tree, &path);
799         strbuf_release(&path);
800 }