git.oblomov.eu Git - git/blob - 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 #include "promisor-remote.h"
   9 #include "sparse-index.h"
  10
  11 #ifndef DEBUG_CACHE_TREE
  12 #define DEBUG_CACHE_TREE 0
  13 #endif
  14
  15 struct cache_tree *cache_tree(void)
  16 {
  17         struct cache_tree *it = xcalloc(1, sizeof(struct cache_tree));
  18         it->entry_count = -1;
  19         return it;
  20 }
  21
  22 void cache_tree_free(struct cache_tree **it_p)
  23 {
  24         int i;
  25         struct cache_tree *it = *it_p;
  26
  27         if (!it)
  28                 return;
  29         for (i = 0; i < it->subtree_nr; i++)
  30                 if (it->down[i]) {
  31                         cache_tree_free(&it->down[i]->cache_tree);
  32                         free(it->down[i]);
  33                 }
  34         free(it->down);
  35         free(it);
  36         *it_p = NULL;
  37 }
  38
  39 static int subtree_name_cmp(const char *one, int onelen,
  40                             const char *two, int twolen)
  41 {
  42         if (onelen < twolen)
  43                 return -1;
  44         if (twolen < onelen)
  45                 return 1;
  46         return memcmp(one, two, onelen);
  47 }
  48
  49 int cache_tree_subtree_pos(struct cache_tree *it, const char *path, int pathlen)
  50 {
  51         struct cache_tree_sub **down = it->down;
  52         int lo, hi;
  53         lo = 0;
  54         hi = it->subtree_nr;
  55         while (lo < hi) {
  56                 int mi = lo + (hi - lo) / 2;
  57                 struct cache_tree_sub *mdl = down[mi];
  58                 int cmp = subtree_name_cmp(path, pathlen,
  59                                            mdl->name, mdl->namelen);
  60                 if (!cmp)
  61                         return mi;
  62                 if (cmp < 0)
  63                         hi = mi;
  64                 else
  65                         lo = mi + 1;
  66         }
  67         return -lo-1;
  68 }
  69
  70 static struct cache_tree_sub *find_subtree(struct cache_tree *it,
  71                                            const char *path,
  72                                            int pathlen,
  73                                            int create)
  74 {
  75         struct cache_tree_sub *down;
  76         int pos = cache_tree_subtree_pos(it, path, pathlen);
  77         if (0 <= pos)
  78                 return it->down[pos];
  79         if (!create)
  80                 return NULL;
  81
  82         pos = -pos-1;
  83         ALLOC_GROW(it->down, it->subtree_nr + 1, it->subtree_alloc);
  84         it->subtree_nr++;
  85
  86         FLEX_ALLOC_MEM(down, name, path, pathlen);
  87         down->cache_tree = NULL;
  88         down->namelen = pathlen;
  89
  90         if (pos < it->subtree_nr)
  91                 MOVE_ARRAY(it->down + pos + 1, it->down + pos,
  92                            it->subtree_nr - pos - 1);
  93         it->down[pos] = down;
  94         return down;
  95 }
  96
  97 struct cache_tree_sub *cache_tree_sub(struct cache_tree *it, const char *path)
  98 {
  99         int pathlen = strlen(path);
 100         return find_subtree(it, path, pathlen, 1);
 101 }
 102
 103 static int do_invalidate_path(struct cache_tree *it, const char *path)
 104 {
 105         /* a/b/c
 106          * ==> invalidate self
 107          * ==> find "a", have it invalidate "b/c"
 108          * a
 109          * ==> invalidate self
 110          * ==> if "a" exists as a subtree, remove it.
 111          */
 112         const char *slash;
 113         int namelen;
 114         struct cache_tree_sub *down;
 115
 116 #if DEBUG_CACHE_TREE
 117         fprintf(stderr, "cache-tree invalidate <%s>\n", path);
 118 #endif
 119
 120         if (!it)
 121                 return 0;
 122         slash = strchrnul(path, '/');
 123         namelen = slash - path;
 124         it->entry_count = -1;
 125         if (!*slash) {
 126                 int pos;
 127                 pos = cache_tree_subtree_pos(it, path, namelen);
 128                 if (0 <= pos) {
 129                         cache_tree_free(&it->down[pos]->cache_tree);
 130                         free(it->down[pos]);
 131                         /* 0 1 2 3 4 5
 132                          *       ^     ^subtree_nr = 6
 133                          *       pos
 134                          * move 4 and 5 up one place (2 entries)
 135                          * 2 = 6 - 3 - 1 = subtree_nr - pos - 1
 136                          */
 137                         MOVE_ARRAY(it->down + pos, it->down + pos + 1,
 138                                    it->subtree_nr - pos - 1);
 139                         it->subtree_nr--;
 140                 }
 141                 return 1;
 142         }
 143         down = find_subtree(it, path, namelen, 0);
 144         if (down)
 145                 do_invalidate_path(down->cache_tree, slash + 1);
 146         return 1;
 147 }
 148
 149 void cache_tree_invalidate_path(struct index_state *istate, const char *path)
 150 {
 151         if (do_invalidate_path(istate->cache_tree, path))
 152                 istate->cache_changed |= CACHE_TREE_CHANGED;
 153 }
 154
 155 static int verify_cache(struct index_state *istate, int flags)
 156 {
 157         unsigned i, funny;
 158         int silent = flags & WRITE_TREE_SILENT;
 159
 160         /* Verify that the tree is merged */
 161         funny = 0;
 162         for (i = 0; i < istate->cache_nr; i++) {
 163                 const struct cache_entry *ce = istate->cache[i];
 164                 if (ce_stage(ce)) {
 165                         if (silent)
 166                                 return -1;
 167                         if (10 < ++funny) {
 168                                 fprintf(stderr, "...\n");
 169                                 break;
 170                         }
 171                         fprintf(stderr, "%s: unmerged (%s)\n",
 172                                 ce->name, oid_to_hex(&ce->oid));
 173                 }
 174         }
 175         if (funny)
 176                 return -1;
 177
 178         /* Also verify that the cache does not have path and path/file
 179          * at the same time.  At this point we know the cache has only
 180          * stage 0 entries.
 181          */
 182         funny = 0;
 183         for (i = 0; i + 1 < istate->cache_nr; i++) {
 184                 /* path/file always comes after path because of the way
 185                  * the cache is sorted.  Also path can appear only once,
 186                  * which means conflicting one would immediately follow.
 187                  */
 188                 const struct cache_entry *this_ce = istate->cache[i];
 189                 const struct cache_entry *next_ce = istate->cache[i + 1];
 190                 const char *this_name = this_ce->name;
 191                 const char *next_name = next_ce->name;
 192                 int this_len = ce_namelen(this_ce);
 193                 if (this_len < ce_namelen(next_ce) &&
 194                     next_name[this_len] == '/' &&
 195                     strncmp(this_name, next_name, this_len) == 0) {
 196                         if (10 < ++funny) {
 197                                 fprintf(stderr, "...\n");
 198                                 break;
 199                         }
 200                         fprintf(stderr, "You have both %s and %s\n",
 201                                 this_name, next_name);
 202                 }
 203         }
 204         if (funny)
 205                 return -1;
 206         return 0;
 207 }
 208
 209 static void discard_unused_subtrees(struct cache_tree *it)
 210 {
 211         struct cache_tree_sub **down = it->down;
 212         int nr = it->subtree_nr;
 213         int dst, src;
 214         for (dst = src = 0; src < nr; src++) {
 215                 struct cache_tree_sub *s = down[src];
 216                 if (s->used)
 217                         down[dst++] = s;
 218                 else {
 219                         cache_tree_free(&s->cache_tree);
 220                         free(s);
 221                         it->subtree_nr--;
 222                 }
 223         }
 224 }
 225
 226 int cache_tree_fully_valid(struct cache_tree *it)
 227 {
 228         int i;
 229         if (!it)
 230                 return 0;
 231         if (it->entry_count < 0 || !has_object_file(&it->oid))
 232                 return 0;
 233         for (i = 0; i < it->subtree_nr; i++) {
 234                 if (!cache_tree_fully_valid(it->down[i]->cache_tree))
 235                         return 0;
 236         }
 237         return 1;
 238 }
 239
 240 static int update_one(struct cache_tree *it,
 241                       struct cache_entry **cache,
 242                       int entries,
 243                       const char *base,
 244                       int baselen,
 245                       int *skip_count,
 246                       int flags)
 247 {
 248         struct strbuf buffer;
 249         int missing_ok = flags & WRITE_TREE_MISSING_OK;
 250         int dryrun = flags & WRITE_TREE_DRY_RUN;
 251         int repair = flags & WRITE_TREE_REPAIR;
 252         int to_invalidate = 0;
 253         int i;
 254
 255         assert(!(dryrun && repair));
 256
 257         *skip_count = 0;
 258
 259         /*
 260          * If the first entry of this region is a sparse directory
 261          * entry corresponding exactly to 'base', then this cache_tree
 262          * struct is a "leaf" in the data structure, pointing to the
 263          * tree OID specified in the entry.
 264          */
 265         if (entries > 0) {
 266                 const struct cache_entry *ce = cache[0];
 267
 268                 if (S_ISSPARSEDIR(ce->ce_mode) &&
 269                     ce->ce_namelen == baselen &&
 270                     !strncmp(ce->name, base, baselen)) {
 271                         it->entry_count = 1;
 272                         oidcpy(&it->oid, &ce->oid);
 273                         return 1;
 274                 }
 275         }
 276
 277         if (0 <= it->entry_count && has_object_file(&it->oid))
 278                 return it->entry_count;
 279
 280         /*
 281          * We first scan for subtrees and update them; we start by
 282          * marking existing subtrees -- the ones that are unmarked
 283          * should not be in the result.
 284          */
 285         for (i = 0; i < it->subtree_nr; i++)
 286                 it->down[i]->used = 0;
 287
 288         /*
 289          * Find the subtrees and update them.
 290          */
 291         i = 0;
 292         while (i < entries) {
 293                 const struct cache_entry *ce = cache[i];
 294                 struct cache_tree_sub *sub;
 295                 const char *path, *slash;
 296                 int pathlen, sublen, subcnt, subskip;
 297
 298                 path = ce->name;
 299                 pathlen = ce_namelen(ce);
 300                 if (pathlen <= baselen || memcmp(base, path, baselen))
 301                         break; /* at the end of this level */
 302
 303                 slash = strchr(path + baselen, '/');
 304                 if (!slash) {
 305                         i++;
 306                         continue;
 307                 }
 308                 /*
 309                  * a/bbb/c (base = a/, slash = /c)
 310                  * ==>
 311                  * path+baselen = bbb/c, sublen = 3
 312                  */
 313                 sublen = slash - (path + baselen);
 314                 sub = find_subtree(it, path + baselen, sublen, 1);
 315                 if (!sub->cache_tree)
 316                         sub->cache_tree = cache_tree();
 317                 subcnt = update_one(sub->cache_tree,
 318                                     cache + i, entries - i,
 319                                     path,
 320                                     baselen + sublen + 1,
 321                                     &subskip,
 322                                     flags);
 323                 if (subcnt < 0)
 324                         return subcnt;
 325                 if (!subcnt)
 326                         die("index cache-tree records empty sub-tree");
 327                 i += subcnt;
 328                 sub->count = subcnt; /* to be used in the next loop */
 329                 *skip_count += subskip;
 330                 sub->used = 1;
 331         }
 332
 333         discard_unused_subtrees(it);
 334
 335         /*
 336          * Then write out the tree object for this level.
 337          */
 338         strbuf_init(&buffer, 8192);
 339
 340         i = 0;
 341         while (i < entries) {
 342                 const struct cache_entry *ce = cache[i];
 343                 struct cache_tree_sub *sub = NULL;
 344                 const char *path, *slash;
 345                 int pathlen, entlen;
 346                 const struct object_id *oid;
 347                 unsigned mode;
 348                 int expected_missing = 0;
 349                 int contains_ita = 0;
 350                 int ce_missing_ok;
 351
 352                 path = ce->name;
 353                 pathlen = ce_namelen(ce);
 354                 if (pathlen <= baselen || memcmp(base, path, baselen))
 355                         break; /* at the end of this level */
 356
 357                 slash = strchr(path + baselen, '/');
 358                 if (slash) {
 359                         entlen = slash - (path + baselen);
 360                         sub = find_subtree(it, path + baselen, entlen, 0);
 361                         if (!sub)
 362                                 die("cache-tree.c: '%.*s' in '%s' not found",
 363                                     entlen, path + baselen, path);
 364                         i += sub->count;
 365                         oid = &sub->cache_tree->oid;
 366                         mode = S_IFDIR;
 367                         contains_ita = sub->cache_tree->entry_count < 0;
 368                         if (contains_ita) {
 369                                 to_invalidate = 1;
 370                                 expected_missing = 1;
 371                         }
 372                 }
 373                 else {
 374                         oid = &ce->oid;
 375                         mode = ce->ce_mode;
 376                         entlen = pathlen - baselen;
 377                         i++;
 378                 }
 379
 380                 ce_missing_ok = mode == S_IFGITLINK || missing_ok ||
 381                         (has_promisor_remote() &&
 382                          ce_skip_worktree(ce));
 383                 if (is_null_oid(oid) ||
 384                     (!ce_missing_ok && !has_object_file(oid))) {
 385                         strbuf_release(&buffer);
 386                         if (expected_missing)
 387                                 return -1;
 388                         return error("invalid object %06o %s for '%.*s'",
 389                                 mode, oid_to_hex(oid), entlen+baselen, path);
 390                 }
 391
 392                 /*
 393                  * CE_REMOVE entries are removed before the index is
 394                  * written to disk. Skip them to remain consistent
 395                  * with the future on-disk index.
 396                  */
 397                 if (ce->ce_flags & CE_REMOVE) {
 398                         *skip_count = *skip_count + 1;
 399                         continue;
 400                 }
 401
 402                 /*
 403                  * CE_INTENT_TO_ADD entries exist on on-disk index but
 404                  * they are not part of generated trees. Invalidate up
 405                  * to root to force cache-tree users to read elsewhere.
 406                  */
 407                 if (!sub && ce_intent_to_add(ce)) {
 408                         to_invalidate = 1;
 409                         continue;
 410                 }
 411
 412                 /*
 413                  * "sub" can be an empty tree if all subentries are i-t-a.
 414                  */
 415                 if (contains_ita && is_empty_tree_oid(oid))
 416                         continue;
 417
 418                 strbuf_grow(&buffer, entlen + 100);
 419                 strbuf_addf(&buffer, "%o %.*s%c", mode, entlen, path + baselen, '\0');
 420                 strbuf_add(&buffer, oid->hash, the_hash_algo->rawsz);
 421
 422 #if DEBUG_CACHE_TREE
 423                 fprintf(stderr, "cache-tree update-one %o %.*s\n",
 424                         mode, entlen, path + baselen);
 425 #endif
 426         }
 427
 428         if (repair) {
 429                 struct object_id oid;
 430                 hash_object_file(the_hash_algo, buffer.buf, buffer.len,
 431                                  tree_type, &oid);
 432                 if (has_object_file_with_flags(&oid, OBJECT_INFO_SKIP_FETCH_OBJECT))
 433                         oidcpy(&it->oid, &oid);
 434                 else
 435                         to_invalidate = 1;
 436         } else if (dryrun) {
 437                 hash_object_file(the_hash_algo, buffer.buf, buffer.len,
 438                                  tree_type, &it->oid);
 439         } else if (write_object_file(buffer.buf, buffer.len, tree_type,
 440                                      &it->oid)) {
 441                 strbuf_release(&buffer);
 442                 return -1;
 443         }
 444
 445         strbuf_release(&buffer);
 446         it->entry_count = to_invalidate ? -1 : i - *skip_count;
 447 #if DEBUG_CACHE_TREE
 448         fprintf(stderr, "cache-tree update-one (%d ent, %d subtree) %s\n",
 449                 it->entry_count, it->subtree_nr,
 450                 oid_to_hex(&it->oid));
 451 #endif
 452         return i;
 453 }
 454
 455 int cache_tree_update(struct index_state *istate, int flags)
 456 {
 457         int skip, i;
 458
 459         i = verify_cache(istate, flags);
 460
 461         if (i)
 462                 return i;
 463
 464         ensure_full_index(istate);
 465
 466         if (!istate->cache_tree)
 467                 istate->cache_tree = cache_tree();
 468
 469         trace_performance_enter();
 470         trace2_region_enter("cache_tree", "update", the_repository);
 471         i = update_one(istate->cache_tree, istate->cache, istate->cache_nr,
 472                        "", 0, &skip, flags);
 473         trace2_region_leave("cache_tree", "update", the_repository);
 474         trace_performance_leave("cache_tree_update");
 475         if (i < 0)
 476                 return i;
 477         istate->cache_changed |= CACHE_TREE_CHANGED;
 478         return 0;
 479 }
 480
 481 static void write_one(struct strbuf *buffer, struct cache_tree *it,
 482                       const char *path, int pathlen)
 483 {
 484         int i;
 485
 486         /* One "cache-tree" entry consists of the following:
 487          * path (NUL terminated)
 488          * entry_count, subtree_nr ("%d %d\n")
 489          * tree-sha1 (missing if invalid)
 490          * subtree_nr "cache-tree" entries for subtrees.
 491          */
 492         strbuf_grow(buffer, pathlen + 100);
 493         strbuf_add(buffer, path, pathlen);
 494         strbuf_addf(buffer, "%c%d %d\n", 0, it->entry_count, it->subtree_nr);
 495
 496 #if DEBUG_CACHE_TREE
 497         if (0 <= it->entry_count)
 498                 fprintf(stderr, "cache-tree <%.*s> (%d ent, %d subtree) %s\n",
 499                         pathlen, path, it->entry_count, it->subtree_nr,
 500                         oid_to_hex(&it->oid));
 501         else
 502                 fprintf(stderr, "cache-tree <%.*s> (%d subtree) invalid\n",
 503                         pathlen, path, it->subtree_nr);
 504 #endif
 505
 506         if (0 <= it->entry_count) {
 507                 strbuf_add(buffer, it->oid.hash, the_hash_algo->rawsz);
 508         }
 509         for (i = 0; i < it->subtree_nr; i++) {
 510                 struct cache_tree_sub *down = it->down[i];
 511                 if (i) {
 512                         struct cache_tree_sub *prev = it->down[i-1];
 513                         if (subtree_name_cmp(down->name, down->namelen,
 514                                              prev->name, prev->namelen) <= 0)
 515                                 die("fatal - unsorted cache subtree");
 516                 }
 517                 write_one(buffer, down->cache_tree, down->name, down->namelen);
 518         }
 519 }
 520
 521 void cache_tree_write(struct strbuf *sb, struct cache_tree *root)
 522 {
 523         trace2_region_enter("cache_tree", "write", the_repository);
 524         write_one(sb, root, "", 0);
 525         trace2_region_leave("cache_tree", "write", the_repository);
 526 }
 527
 528 static struct cache_tree *read_one(const char **buffer, unsigned long *size_p)
 529 {
 530         const char *buf = *buffer;
 531         unsigned long size = *size_p;
 532         const char *cp;
 533         char *ep;
 534         struct cache_tree *it;
 535         int i, subtree_nr;
 536         const unsigned rawsz = the_hash_algo->rawsz;
 537
 538         it = NULL;
 539         /* skip name, but make sure name exists */
 540         while (size && *buf) {
 541                 size--;
 542                 buf++;
 543         }
 544         if (!size)
 545                 goto free_return;
 546         buf++; size--;
 547         it = cache_tree();
 548
 549         cp = buf;
 550         it->entry_count = strtol(cp, &ep, 10);
 551         if (cp == ep)
 552                 goto free_return;
 553         cp = ep;
 554         subtree_nr = strtol(cp, &ep, 10);
 555         if (cp == ep)
 556                 goto free_return;
 557         while (size && *buf && *buf != '\n') {
 558                 size--;
 559                 buf++;
 560         }
 561         if (!size)
 562                 goto free_return;
 563         buf++; size--;
 564         if (0 <= it->entry_count) {
 565                 if (size < rawsz)
 566                         goto free_return;
 567                 oidread(&it->oid, (const unsigned char *)buf);
 568                 buf += rawsz;
 569                 size -= rawsz;
 570         }
 571
 572 #if DEBUG_CACHE_TREE
 573         if (0 <= it->entry_count)
 574                 fprintf(stderr, "cache-tree <%s> (%d ent, %d subtree) %s\n",
 575                         *buffer, it->entry_count, subtree_nr,
 576                         oid_to_hex(&it->oid));
 577         else
 578                 fprintf(stderr, "cache-tree <%s> (%d subtrees) invalid\n",
 579                         *buffer, subtree_nr);
 580 #endif
 581
 582         /*
 583          * Just a heuristic -- we do not add directories that often but
 584          * we do not want to have to extend it immediately when we do,
 585          * hence +2.
 586          */
 587         it->subtree_alloc = subtree_nr + 2;
 588         CALLOC_ARRAY(it->down, it->subtree_alloc);
 589         for (i = 0; i < subtree_nr; i++) {
 590                 /* read each subtree */
 591                 struct cache_tree *sub;
 592                 struct cache_tree_sub *subtree;
 593                 const char *name = buf;
 594
 595                 sub = read_one(&buf, &size);
 596                 if (!sub)
 597                         goto free_return;
 598                 subtree = cache_tree_sub(it, name);
 599                 subtree->cache_tree = sub;
 600         }
 601         if (subtree_nr != it->subtree_nr)
 602                 die("cache-tree: internal error");
 603         *buffer = buf;
 604         *size_p = size;
 605         return it;
 606
 607  free_return:
 608         cache_tree_free(&it);
 609         return NULL;
 610 }
 611
 612 struct cache_tree *cache_tree_read(const char *buffer, unsigned long size)
 613 {
 614         struct cache_tree *result;
 615
 616         if (buffer[0])
 617                 return NULL; /* not the whole tree */
 618
 619         trace2_region_enter("cache_tree", "read", the_repository);
 620         result = read_one(&buffer, &size);
 621         trace2_region_leave("cache_tree", "read", the_repository);
 622
 623         return result;
 624 }
 625
 626 static struct cache_tree *cache_tree_find(struct cache_tree *it, const char *path)
 627 {
 628         if (!it)
 629                 return NULL;
 630         while (*path) {
 631                 const char *slash;
 632                 struct cache_tree_sub *sub;
 633
 634                 slash = strchrnul(path, '/');
 635                 /*
 636                  * Between path and slash is the name of the subtree
 637                  * to look for.
 638                  */
 639                 sub = find_subtree(it, path, slash - path, 0);
 640                 if (!sub)
 641                         return NULL;
 642                 it = sub->cache_tree;
 643
 644                 path = slash;
 645                 while (*path == '/')
 646                         path++;
 647         }
 648         return it;
 649 }
 650
 651 static int write_index_as_tree_internal(struct object_id *oid,
 652                                         struct index_state *index_state,
 653                                         int cache_tree_valid,
 654                                         int flags,
 655                                         const char *prefix)
 656 {
 657         if (flags & WRITE_TREE_IGNORE_CACHE_TREE) {
 658                 cache_tree_free(&index_state->cache_tree);
 659                 cache_tree_valid = 0;
 660         }
 661
 662         if (!cache_tree_valid && cache_tree_update(index_state, flags) < 0)
 663                 return WRITE_TREE_UNMERGED_INDEX;
 664
 665         if (prefix) {
 666                 struct cache_tree *subtree;
 667                 subtree = cache_tree_find(index_state->cache_tree, prefix);
 668                 if (!subtree)
 669                         return WRITE_TREE_PREFIX_ERROR;
 670                 oidcpy(oid, &subtree->oid);
 671         }
 672         else
 673                 oidcpy(oid, &index_state->cache_tree->oid);
 674
 675         return 0;
 676 }
 677
 678 struct tree* write_in_core_index_as_tree(struct repository *repo) {
 679         struct object_id o;
 680         int was_valid, ret;
 681
 682         struct index_state *index_state = repo->index;
 683         was_valid = index_state->cache_tree &&
 684                     cache_tree_fully_valid(index_state->cache_tree);
 685
 686         ret = write_index_as_tree_internal(&o, index_state, was_valid, 0, NULL);
 687         if (ret == WRITE_TREE_UNMERGED_INDEX) {
 688                 int i;
 689                 fprintf(stderr, "BUG: There are unmerged index entries:\n");
 690                 for (i = 0; i < index_state->cache_nr; i++) {
 691                         const struct cache_entry *ce = index_state->cache[i];
 692                         if (ce_stage(ce))
 693                                 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
 694                                         (int)ce_namelen(ce), ce->name);
 695                 }
 696                 BUG("unmerged index entries when writing inmemory index");
 697         }
 698
 699         return lookup_tree(repo, &index_state->cache_tree->oid);
 700 }
 701
 702
 703 int write_index_as_tree(struct object_id *oid, struct index_state *index_state, const char *index_path, int flags, const char *prefix)
 704 {
 705         int entries, was_valid;
 706         struct lock_file lock_file = LOCK_INIT;
 707         int ret;
 708
 709         hold_lock_file_for_update(&lock_file, index_path, LOCK_DIE_ON_ERROR);
 710
 711         entries = read_index_from(index_state, index_path, get_git_dir());
 712         if (entries < 0) {
 713                 ret = WRITE_TREE_UNREADABLE_INDEX;
 714                 goto out;
 715         }
 716
 717         was_valid = !(flags & WRITE_TREE_IGNORE_CACHE_TREE) &&
 718                     index_state->cache_tree &&
 719                     cache_tree_fully_valid(index_state->cache_tree);
 720
 721         ret = write_index_as_tree_internal(oid, index_state, was_valid, flags,
 722                                            prefix);
 723         if (!ret && !was_valid) {
 724                 write_locked_index(index_state, &lock_file, COMMIT_LOCK);
 725                 /* Not being able to write is fine -- we are only interested
 726                  * in updating the cache-tree part, and if the next caller
 727                  * ends up using the old index with unupdated cache-tree part
 728                  * it misses the work we did here, but that is just a
 729                  * performance penalty and not a big deal.
 730                  */
 731         }
 732
 733 out:
 734         rollback_lock_file(&lock_file);
 735         return ret;
 736 }
 737
 738 static void prime_cache_tree_rec(struct repository *r,
 739                                  struct cache_tree *it,
 740                                  struct tree *tree)
 741 {
 742         struct tree_desc desc;
 743         struct name_entry entry;
 744         int cnt;
 745
 746         oidcpy(&it->oid, &tree->object.oid);
 747         init_tree_desc(&desc, tree->buffer, tree->size);
 748         cnt = 0;
 749         while (tree_entry(&desc, &entry)) {
 750                 if (!S_ISDIR(entry.mode))
 751                         cnt++;
 752                 else {
 753                         struct cache_tree_sub *sub;
 754                         struct tree *subtree = lookup_tree(r, &entry.oid);
 755                         if (!subtree->object.parsed)
 756                                 parse_tree(subtree);
 757                         sub = cache_tree_sub(it, entry.path);
 758                         sub->cache_tree = cache_tree();
 759                         prime_cache_tree_rec(r, sub->cache_tree, subtree);
 760                         cnt += sub->cache_tree->entry_count;
 761                 }
 762         }
 763         it->entry_count = cnt;
 764 }
 765
 766 void prime_cache_tree(struct repository *r,
 767                       struct index_state *istate,
 768                       struct tree *tree)
 769 {
 770         trace2_region_enter("cache-tree", "prime_cache_tree", the_repository);
 771         cache_tree_free(&istate->cache_tree);
 772         istate->cache_tree = cache_tree();
 773
 774         prime_cache_tree_rec(r, istate->cache_tree, tree);
 775         istate->cache_changed |= CACHE_TREE_CHANGED;
 776         trace2_region_leave("cache-tree", "prime_cache_tree", the_repository);
 777 }
 778
 779 /*
 780  * find the cache_tree that corresponds to the current level without
 781  * exploding the full path into textual form.  The root of the
 782  * cache tree is given as "root", and our current level is "info".
 783  * (1) When at root level, info->prev is NULL, so it is "root" itself.
 784  * (2) Otherwise, find the cache_tree that corresponds to one level
 785  *     above us, and find ourselves in there.
 786  */
 787 static struct cache_tree *find_cache_tree_from_traversal(struct cache_tree *root,
 788                                                          struct traverse_info *info)
 789 {
 790         struct cache_tree *our_parent;
 791
 792         if (!info->prev)
 793                 return root;
 794         our_parent = find_cache_tree_from_traversal(root, info->prev);
 795         return cache_tree_find(our_parent, info->name);
 796 }
 797
 798 int cache_tree_matches_traversal(struct cache_tree *root,
 799                                  struct name_entry *ent,
 800                                  struct traverse_info *info)
 801 {
 802         struct cache_tree *it;
 803
 804         it = find_cache_tree_from_traversal(root, info);
 805         it = cache_tree_find(it, ent->path);
 806         if (it && it->entry_count > 0 && oideq(&ent->oid, &it->oid))
 807                 return it->entry_count;
 808         return 0;
 809 }
 810
 811 static void verify_one_sparse(struct repository *r,
 812                               struct index_state *istate,
 813                               struct cache_tree *it,
 814                               struct strbuf *path,
 815                               int pos)
 816 {
 817         struct cache_entry *ce = istate->cache[pos];
 818
 819         if (!S_ISSPARSEDIR(ce->ce_mode))
 820                 BUG("directory '%s' is present in index, but not sparse",
 821                     path->buf);
 822 }
 823
 824 static void verify_one(struct repository *r,
 825                        struct index_state *istate,
 826                        struct cache_tree *it,
 827                        struct strbuf *path)
 828 {
 829         int i, pos, len = path->len;
 830         struct strbuf tree_buf = STRBUF_INIT;
 831         struct object_id new_oid;
 832
 833         for (i = 0; i < it->subtree_nr; i++) {
 834                 strbuf_addf(path, "%s/", it->down[i]->name);
 835                 verify_one(r, istate, it->down[i]->cache_tree, path);
 836                 strbuf_setlen(path, len);
 837         }
 838
 839         if (it->entry_count < 0 ||
 840             /* no verification on tests (t7003) that replace trees */
 841             lookup_replace_object(r, &it->oid) != &it->oid)
 842                 return;
 843
 844         if (path->len) {
 845                 pos = index_name_pos(istate, path->buf, path->len);
 846
 847                 if (pos >= 0) {
 848                         verify_one_sparse(r, istate, it, path, pos);
 849                         return;
 850                 }
 851
 852                 pos = -pos - 1;
 853         } else {
 854                 pos = 0;
 855         }
 856
 857         i = 0;
 858         while (i < it->entry_count) {
 859                 struct cache_entry *ce = istate->cache[pos + i];
 860                 const char *slash;
 861                 struct cache_tree_sub *sub = NULL;
 862                 const struct object_id *oid;
 863                 const char *name;
 864                 unsigned mode;
 865                 int entlen;
 866
 867                 if (ce->ce_flags & (CE_STAGEMASK | CE_INTENT_TO_ADD | CE_REMOVE))
 868                         BUG("%s with flags 0x%x should not be in cache-tree",
 869                             ce->name, ce->ce_flags);
 870                 name = ce->name + path->len;
 871                 slash = strchr(name, '/');
 872                 if (slash) {
 873                         entlen = slash - name;
 874                         sub = find_subtree(it, ce->name + path->len, entlen, 0);
 875                         if (!sub || sub->cache_tree->entry_count < 0)
 876                                 BUG("bad subtree '%.*s'", entlen, name);
 877                         oid = &sub->cache_tree->oid;
 878                         mode = S_IFDIR;
 879                         i += sub->cache_tree->entry_count;
 880                 } else {
 881                         oid = &ce->oid;
 882                         mode = ce->ce_mode;
 883                         entlen = ce_namelen(ce) - path->len;
 884                         i++;
 885                 }
 886                 strbuf_addf(&tree_buf, "%o %.*s%c", mode, entlen, name, '\0');
 887                 strbuf_add(&tree_buf, oid->hash, r->hash_algo->rawsz);
 888         }
 889         hash_object_file(r->hash_algo, tree_buf.buf, tree_buf.len, tree_type,
 890                          &new_oid);
 891         if (!oideq(&new_oid, &it->oid))
 892                 BUG("cache-tree for path %.*s does not match. "
 893                     "Expected %s got %s", len, path->buf,
 894                     oid_to_hex(&new_oid), oid_to_hex(&it->oid));
 895         strbuf_setlen(path, len);
 896         strbuf_release(&tree_buf);
 897 }
 898
 899 void cache_tree_verify(struct repository *r, struct index_state *istate)
 900 {
 901         struct strbuf path = STRBUF_INIT;
 902
 903         if (!istate->cache_tree)
 904                 return;
 905         verify_one(r, istate, istate->cache_tree, &path);
 906         strbuf_release(&path);
 907 }