cache-tree.con commit git-p4: fully support unshelving changelists (89143ac)
   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
  13struct 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
  20void 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
  37static 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
  47static 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
  68static 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
  95struct 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
 101static 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
 147void 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
 153static 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
 206static 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
 223int 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
 237static 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
 428int 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
 446static 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
 486void cache_tree_write(struct strbuf *sb, struct cache_tree *root)
 487{
 488        write_one(sb, root, "", 0);
 489}
 490
 491static 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
 575struct 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
 582static 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
 607int 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
 653out:
 654        rollback_lock_file(&lock_file);
 655        return ret;
 656}
 657
 658static 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
 685void 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 */
 701static 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
 712int 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
 725static 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
 792void 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}