builtin/fsck.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "commit.h"
   4 #include "tree.h"
   5 #include "blob.h"
   6 #include "tag.h"
   7 #include "refs.h"
   8 #include "pack.h"
   9 #include "cache-tree.h"
  10 #include "tree-walk.h"
  11 #include "fsck.h"
  12 #include "parse-options.h"
  13 #include "dir.h"
  14 #include "progress.h"
  15 #include "streaming.h"
  16
  17 #define REACHABLE 0x0001
  18 #define SEEN      0x0002
  19
  20 static int show_root;
  21 static int show_tags;
  22 static int show_unreachable;
  23 static int include_reflogs = 1;
  24 static int check_full = 1;
  25 static int check_strict;
  26 static int keep_cache_objects;
  27 static unsigned char head_sha1[20];
  28 static const char *head_points_at;
  29 static int errors_found;
  30 static int write_lost_and_found;
  31 static int verbose;
  32 static int show_progress = -1;
  33 static int show_dangling = 1;
  34 #define ERROR_OBJECT 01
  35 #define ERROR_REACHABLE 02
  36 #define ERROR_PACK 04
  37
  38 #ifdef NO_D_INO_IN_DIRENT
  39 #define SORT_DIRENT 0
  40 #define DIRENT_SORT_HINT(de) 0
  41 #else
  42 #define SORT_DIRENT 1
  43 #define DIRENT_SORT_HINT(de) ((de)->d_ino)
  44 #endif
  45
  46 static void objreport(struct object *obj, const char *severity,
  47                       const char *err, va_list params)
  48 {
  49         fprintf(stderr, "%s in %s %s: ",
  50                 severity, typename(obj->type), sha1_to_hex(obj->sha1));
  51         vfprintf(stderr, err, params);
  52         fputs("\n", stderr);
  53 }
  54
  55 __attribute__((format (printf, 2, 3)))
  56 static int objerror(struct object *obj, const char *err, ...)
  57 {
  58         va_list params;
  59         va_start(params, err);
  60         errors_found |= ERROR_OBJECT;
  61         objreport(obj, "error", err, params);
  62         va_end(params);
  63         return -1;
  64 }
  65
  66 __attribute__((format (printf, 3, 4)))
  67 static int fsck_error_func(struct object *obj, int type, const char *err, ...)
  68 {
  69         va_list params;
  70         va_start(params, err);
  71         objreport(obj, (type == FSCK_WARN) ? "warning" : "error", err, params);
  72         va_end(params);
  73         return (type == FSCK_WARN) ? 0 : 1;
  74 }
  75
  76 static struct object_array pending;
  77
  78 static int mark_object(struct object *obj, int type, void *data)
  79 {
  80         struct object *parent = data;
  81
  82         /*
  83          * The only case data is NULL or type is OBJ_ANY is when
  84          * mark_object_reachable() calls us.  All the callers of
  85          * that function has non-NULL obj hence ...
  86          */
  87         if (!obj) {
  88                 /* ... these references to parent->fld are safe here */
  89                 printf("broken link from %7s %s\n",
  90                            typename(parent->type), sha1_to_hex(parent->sha1));
  91                 printf("broken link from %7s %s\n",
  92                            (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
  93                 errors_found |= ERROR_REACHABLE;
  94                 return 1;
  95         }
  96
  97         if (type != OBJ_ANY && obj->type != type)
  98                 /* ... and the reference to parent is safe here */
  99                 objerror(parent, "wrong object type in link");
 100
 101         if (obj->flags & REACHABLE)
 102                 return 0;
 103         obj->flags |= REACHABLE;
 104         if (!obj->parsed) {
 105                 if (parent && !has_sha1_file(obj->sha1)) {
 106                         printf("broken link from %7s %s\n",
 107                                  typename(parent->type), sha1_to_hex(parent->sha1));
 108                         printf("              to %7s %s\n",
 109                                  typename(obj->type), sha1_to_hex(obj->sha1));
 110                         errors_found |= ERROR_REACHABLE;
 111                 }
 112                 return 1;
 113         }
 114
 115         add_object_array(obj, (void *) parent, &pending);
 116         return 0;
 117 }
 118
 119 static void mark_object_reachable(struct object *obj)
 120 {
 121         mark_object(obj, OBJ_ANY, NULL);
 122 }
 123
 124 static int traverse_one_object(struct object *obj)
 125 {
 126         int result;
 127         struct tree *tree = NULL;
 128
 129         if (obj->type == OBJ_TREE) {
 130                 obj->parsed = 0;
 131                 tree = (struct tree *)obj;
 132                 if (parse_tree(tree) < 0)
 133                         return 1; /* error already displayed */
 134         }
 135         result = fsck_walk(obj, mark_object, obj);
 136         if (tree) {
 137                 free(tree->buffer);
 138                 tree->buffer = NULL;
 139         }
 140         return result;
 141 }
 142
 143 static int traverse_reachable(void)
 144 {
 145         struct progress *progress = NULL;
 146         unsigned int nr = 0;
 147         int result = 0;
 148         if (show_progress)
 149                 progress = start_progress_delay("Checking connectivity", 0, 0, 2);
 150         while (pending.nr) {
 151                 struct object_array_entry *entry;
 152                 struct object *obj;
 153
 154                 entry = pending.objects + --pending.nr;
 155                 obj = entry->item;
 156                 result |= traverse_one_object(obj);
 157                 display_progress(progress, ++nr);
 158         }
 159         stop_progress(&progress);
 160         return !!result;
 161 }
 162
 163 static int mark_used(struct object *obj, int type, void *data)
 164 {
 165         if (!obj)
 166                 return 1;
 167         obj->used = 1;
 168         return 0;
 169 }
 170
 171 /*
 172  * Check a single reachable object
 173  */
 174 static void check_reachable_object(struct object *obj)
 175 {
 176         /*
 177          * We obviously want the object to be parsed,
 178          * except if it was in a pack-file and we didn't
 179          * do a full fsck
 180          */
 181         if (!obj->parsed) {
 182                 if (has_sha1_pack(obj->sha1))
 183                         return; /* it is in pack - forget about it */
 184                 printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
 185                 errors_found |= ERROR_REACHABLE;
 186                 return;
 187         }
 188 }
 189
 190 /*
 191  * Check a single unreachable object
 192  */
 193 static void check_unreachable_object(struct object *obj)
 194 {
 195         /*
 196          * Missing unreachable object? Ignore it. It's not like
 197          * we miss it (since it can't be reached), nor do we want
 198          * to complain about it being unreachable (since it does
 199          * not exist).
 200          */
 201         if (!obj->parsed)
 202                 return;
 203
 204         /*
 205          * Unreachable object that exists? Show it if asked to,
 206          * since this is something that is prunable.
 207          */
 208         if (show_unreachable) {
 209                 printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
 210                 return;
 211         }
 212
 213         /*
 214          * "!used" means that nothing at all points to it, including
 215          * other unreachable objects. In other words, it's the "tip"
 216          * of some set of unreachable objects, usually a commit that
 217          * got dropped.
 218          *
 219          * Such starting points are more interesting than some random
 220          * set of unreachable objects, so we show them even if the user
 221          * hasn't asked for _all_ unreachable objects. If you have
 222          * deleted a branch by mistake, this is a prime candidate to
 223          * start looking at, for example.
 224          */
 225         if (!obj->used) {
 226                 if (show_dangling)
 227                         printf("dangling %s %s\n", typename(obj->type),
 228                                sha1_to_hex(obj->sha1));
 229                 if (write_lost_and_found) {
 230                         char *filename = git_path("lost-found/%s/%s",
 231                                 obj->type == OBJ_COMMIT ? "commit" : "other",
 232                                 sha1_to_hex(obj->sha1));
 233                         FILE *f;
 234
 235                         if (safe_create_leading_directories(filename)) {
 236                                 error("Could not create lost-found");
 237                                 return;
 238                         }
 239                         if (!(f = fopen(filename, "w")))
 240                                 die_errno("Could not open '%s'", filename);
 241                         if (obj->type == OBJ_BLOB) {
 242                                 if (stream_blob_to_fd(fileno(f), obj->sha1, NULL, 1))
 243                                         die_errno("Could not write '%s'", filename);
 244                         } else
 245                                 fprintf(f, "%s\n", sha1_to_hex(obj->sha1));
 246                         if (fclose(f))
 247                                 die_errno("Could not finish '%s'",
 248                                           filename);
 249                 }
 250                 return;
 251         }
 252
 253         /*
 254          * Otherwise? It's there, it's unreachable, and some other unreachable
 255          * object points to it. Ignore it - it's not interesting, and we showed
 256          * all the interesting cases above.
 257          */
 258 }
 259
 260 static void check_object(struct object *obj)
 261 {
 262         if (verbose)
 263                 fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1));
 264
 265         if (obj->flags & REACHABLE)
 266                 check_reachable_object(obj);
 267         else
 268                 check_unreachable_object(obj);
 269 }
 270
 271 static void check_connectivity(void)
 272 {
 273         int i, max;
 274
 275         /* Traverse the pending reachable objects */
 276         traverse_reachable();
 277
 278         /* Look up all the requirements, warn about missing objects.. */
 279         max = get_max_object_index();
 280         if (verbose)
 281                 fprintf(stderr, "Checking connectivity (%d objects)\n", max);
 282
 283         for (i = 0; i < max; i++) {
 284                 struct object *obj = get_indexed_object(i);
 285
 286                 if (obj)
 287                         check_object(obj);
 288         }
 289 }
 290
 291 static int fsck_obj(struct object *obj)
 292 {
 293         if (obj->flags & SEEN)
 294                 return 0;
 295         obj->flags |= SEEN;
 296
 297         if (verbose)
 298                 fprintf(stderr, "Checking %s %s\n",
 299                         typename(obj->type), sha1_to_hex(obj->sha1));
 300
 301         if (fsck_walk(obj, mark_used, NULL))
 302                 objerror(obj, "broken links");
 303         if (fsck_object(obj, check_strict, fsck_error_func))
 304                 return -1;
 305
 306         if (obj->type == OBJ_TREE) {
 307                 struct tree *item = (struct tree *) obj;
 308
 309                 free(item->buffer);
 310                 item->buffer = NULL;
 311         }
 312
 313         if (obj->type == OBJ_COMMIT) {
 314                 struct commit *commit = (struct commit *) obj;
 315
 316                 free(commit->buffer);
 317                 commit->buffer = NULL;
 318
 319                 if (!commit->parents && show_root)
 320                         printf("root %s\n", sha1_to_hex(commit->object.sha1));
 321         }
 322
 323         if (obj->type == OBJ_TAG) {
 324                 struct tag *tag = (struct tag *) obj;
 325
 326                 if (show_tags && tag->tagged) {
 327                         printf("tagged %s %s", typename(tag->tagged->type), sha1_to_hex(tag->tagged->sha1));
 328                         printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
 329                 }
 330         }
 331
 332         return 0;
 333 }
 334
 335 static int fsck_sha1(const unsigned char *sha1)
 336 {
 337         struct object *obj = parse_object(sha1);
 338         if (!obj) {
 339                 errors_found |= ERROR_OBJECT;
 340                 return error("%s: object corrupt or missing",
 341                              sha1_to_hex(sha1));
 342         }
 343         return fsck_obj(obj);
 344 }
 345
 346 static int fsck_obj_buffer(const unsigned char *sha1, enum object_type type,
 347                            unsigned long size, void *buffer, int *eaten)
 348 {
 349         struct object *obj;
 350         obj = parse_object_buffer(sha1, type, size, buffer, eaten);
 351         if (!obj) {
 352                 errors_found |= ERROR_OBJECT;
 353                 return error("%s: object corrupt or missing", sha1_to_hex(sha1));
 354         }
 355         return fsck_obj(obj);
 356 }
 357
 358 /*
 359  * This is the sorting chunk size: make it reasonably
 360  * big so that we can sort well..
 361  */
 362 #define MAX_SHA1_ENTRIES (1024)
 363
 364 struct sha1_entry {
 365         unsigned long ino;
 366         unsigned char sha1[20];
 367 };
 368
 369 static struct {
 370         unsigned long nr;
 371         struct sha1_entry *entry[MAX_SHA1_ENTRIES];
 372 } sha1_list;
 373
 374 static int ino_compare(const void *_a, const void *_b)
 375 {
 376         const struct sha1_entry *a = _a, *b = _b;
 377         unsigned long ino1 = a->ino, ino2 = b->ino;
 378         return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
 379 }
 380
 381 static void fsck_sha1_list(void)
 382 {
 383         int i, nr = sha1_list.nr;
 384
 385         if (SORT_DIRENT)
 386                 qsort(sha1_list.entry, nr,
 387                       sizeof(struct sha1_entry *), ino_compare);
 388         for (i = 0; i < nr; i++) {
 389                 struct sha1_entry *entry = sha1_list.entry[i];
 390                 unsigned char *sha1 = entry->sha1;
 391
 392                 sha1_list.entry[i] = NULL;
 393                 fsck_sha1(sha1);
 394                 free(entry);
 395         }
 396         sha1_list.nr = 0;
 397 }
 398
 399 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
 400 {
 401         struct sha1_entry *entry = xmalloc(sizeof(*entry));
 402         int nr;
 403
 404         entry->ino = ino;
 405         hashcpy(entry->sha1, sha1);
 406         nr = sha1_list.nr;
 407         if (nr == MAX_SHA1_ENTRIES) {
 408                 fsck_sha1_list();
 409                 nr = 0;
 410         }
 411         sha1_list.entry[nr] = entry;
 412         sha1_list.nr = ++nr;
 413 }
 414
 415 static inline int is_loose_object_file(struct dirent *de,
 416                                        char *name, unsigned char *sha1)
 417 {
 418         if (strlen(de->d_name) != 38)
 419                 return 0;
 420         memcpy(name + 2, de->d_name, 39);
 421         return !get_sha1_hex(name, sha1);
 422 }
 423
 424 static void fsck_dir(int i, char *path)
 425 {
 426         DIR *dir = opendir(path);
 427         struct dirent *de;
 428         char name[100];
 429
 430         if (!dir)
 431                 return;
 432
 433         if (verbose)
 434                 fprintf(stderr, "Checking directory %s\n", path);
 435
 436         sprintf(name, "%02x", i);
 437         while ((de = readdir(dir)) != NULL) {
 438                 unsigned char sha1[20];
 439
 440                 if (is_dot_or_dotdot(de->d_name))
 441                         continue;
 442                 if (is_loose_object_file(de, name, sha1)) {
 443                         add_sha1_list(sha1, DIRENT_SORT_HINT(de));
 444                         continue;
 445                 }
 446                 if (!prefixcmp(de->d_name, "tmp_obj_"))
 447                         continue;
 448                 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
 449         }
 450         closedir(dir);
 451 }
 452
 453 static int default_refs;
 454
 455 static int fsck_handle_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 456                 const char *email, unsigned long timestamp, int tz,
 457                 const char *message, void *cb_data)
 458 {
 459         struct object *obj;
 460
 461         if (verbose)
 462                 fprintf(stderr, "Checking reflog %s->%s\n",
 463                         sha1_to_hex(osha1), sha1_to_hex(nsha1));
 464
 465         if (!is_null_sha1(osha1)) {
 466                 obj = lookup_object(osha1);
 467                 if (obj) {
 468                         obj->used = 1;
 469                         mark_object_reachable(obj);
 470                 }
 471         }
 472         obj = lookup_object(nsha1);
 473         if (obj) {
 474                 obj->used = 1;
 475                 mark_object_reachable(obj);
 476         }
 477         return 0;
 478 }
 479
 480 static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, int flag, void *cb_data)
 481 {
 482         for_each_reflog_ent(logname, fsck_handle_reflog_ent, NULL);
 483         return 0;
 484 }
 485
 486 static int is_branch(const char *refname)
 487 {
 488         return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
 489 }
 490
 491 static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 492 {
 493         struct object *obj;
 494
 495         obj = parse_object(sha1);
 496         if (!obj) {
 497                 error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
 498                 /* We'll continue with the rest despite the error.. */
 499                 return 0;
 500         }
 501         if (obj->type != OBJ_COMMIT && is_branch(refname))
 502                 error("%s: not a commit", refname);
 503         default_refs++;
 504         obj->used = 1;
 505         mark_object_reachable(obj);
 506
 507         return 0;
 508 }
 509
 510 static void get_default_heads(void)
 511 {
 512         if (head_points_at && !is_null_sha1(head_sha1))
 513                 fsck_handle_ref("HEAD", head_sha1, 0, NULL);
 514         for_each_ref(fsck_handle_ref, NULL);
 515         if (include_reflogs)
 516                 for_each_reflog(fsck_handle_reflog, NULL);
 517
 518         /*
 519          * Not having any default heads isn't really fatal, but
 520          * it does mean that "--unreachable" no longer makes any
 521          * sense (since in this case everything will obviously
 522          * be unreachable by definition.
 523          *
 524          * Showing dangling objects is valid, though (as those
 525          * dangling objects are likely lost heads).
 526          *
 527          * So we just print a warning about it, and clear the
 528          * "show_unreachable" flag.
 529          */
 530         if (!default_refs) {
 531                 fprintf(stderr, "notice: No default references\n");
 532                 show_unreachable = 0;
 533         }
 534 }
 535
 536 static void fsck_object_dir(const char *path)
 537 {
 538         int i;
 539         struct progress *progress = NULL;
 540
 541         if (verbose)
 542                 fprintf(stderr, "Checking object directory\n");
 543
 544         if (show_progress)
 545                 progress = start_progress("Checking object directories", 256);
 546         for (i = 0; i < 256; i++) {
 547                 static char dir[4096];
 548                 sprintf(dir, "%s/%02x", path, i);
 549                 fsck_dir(i, dir);
 550                 display_progress(progress, i+1);
 551         }
 552         stop_progress(&progress);
 553         fsck_sha1_list();
 554 }
 555
 556 static int fsck_head_link(void)
 557 {
 558         int flag;
 559         int null_is_error = 0;
 560
 561         if (verbose)
 562                 fprintf(stderr, "Checking HEAD link\n");
 563
 564         head_points_at = resolve_ref_unsafe("HEAD", head_sha1, 0, &flag);
 565         if (!head_points_at)
 566                 return error("Invalid HEAD");
 567         if (!strcmp(head_points_at, "HEAD"))
 568                 /* detached HEAD */
 569                 null_is_error = 1;
 570         else if (prefixcmp(head_points_at, "refs/heads/"))
 571                 return error("HEAD points to something strange (%s)",
 572                              head_points_at);
 573         if (is_null_sha1(head_sha1)) {
 574                 if (null_is_error)
 575                         return error("HEAD: detached HEAD points at nothing");
 576                 fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
 577                         head_points_at + 11);
 578         }
 579         return 0;
 580 }
 581
 582 static int fsck_cache_tree(struct cache_tree *it)
 583 {
 584         int i;
 585         int err = 0;
 586
 587         if (verbose)
 588                 fprintf(stderr, "Checking cache tree\n");
 589
 590         if (0 <= it->entry_count) {
 591                 struct object *obj = parse_object(it->sha1);
 592                 if (!obj) {
 593                         error("%s: invalid sha1 pointer in cache-tree",
 594                               sha1_to_hex(it->sha1));
 595                         return 1;
 596                 }
 597                 obj->used = 1;
 598                 mark_object_reachable(obj);
 599                 if (obj->type != OBJ_TREE)
 600                         err |= objerror(obj, "non-tree in cache-tree");
 601         }
 602         for (i = 0; i < it->subtree_nr; i++)
 603                 err |= fsck_cache_tree(it->down[i]->cache_tree);
 604         return err;
 605 }
 606
 607 static char const * const fsck_usage[] = {
 608         "git fsck [options] [<object>...]",
 609         NULL
 610 };
 611
 612 static struct option fsck_opts[] = {
 613         OPT__VERBOSE(&verbose, "be verbose"),
 614         OPT_BOOLEAN(0, "unreachable", &show_unreachable, "show unreachable objects"),
 615         OPT_BOOL(0, "dangling", &show_dangling, "show dangling objects"),
 616         OPT_BOOLEAN(0, "tags", &show_tags, "report tags"),
 617         OPT_BOOLEAN(0, "root", &show_root, "report root nodes"),
 618         OPT_BOOLEAN(0, "cache", &keep_cache_objects, "make index objects head nodes"),
 619         OPT_BOOLEAN(0, "reflogs", &include_reflogs, "make reflogs head nodes (default)"),
 620         OPT_BOOLEAN(0, "full", &check_full, "also consider packs and alternate objects"),
 621         OPT_BOOLEAN(0, "strict", &check_strict, "enable more strict checking"),
 622         OPT_BOOLEAN(0, "lost-found", &write_lost_and_found,
 623                                 "write dangling objects in .git/lost-found"),
 624         OPT_BOOL(0, "progress", &show_progress, "show progress"),
 625         OPT_END(),
 626 };
 627
 628 int cmd_fsck(int argc, const char **argv, const char *prefix)
 629 {
 630         int i, heads;
 631         struct alternate_object_database *alt;
 632
 633         errors_found = 0;
 634         read_replace_refs = 0;
 635
 636         argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0);
 637
 638         if (show_progress == -1)
 639                 show_progress = isatty(2);
 640         if (verbose)
 641                 show_progress = 0;
 642
 643         if (write_lost_and_found) {
 644                 check_full = 1;
 645                 include_reflogs = 0;
 646         }
 647
 648         fsck_head_link();
 649         fsck_object_dir(get_object_directory());
 650
 651         prepare_alt_odb();
 652         for (alt = alt_odb_list; alt; alt = alt->next) {
 653                 char namebuf[PATH_MAX];
 654                 int namelen = alt->name - alt->base;
 655                 memcpy(namebuf, alt->base, namelen);
 656                 namebuf[namelen - 1] = 0;
 657                 fsck_object_dir(namebuf);
 658         }
 659
 660         if (check_full) {
 661                 struct packed_git *p;
 662                 uint32_t total = 0, count = 0;
 663                 struct progress *progress = NULL;
 664
 665                 prepare_packed_git();
 666
 667                 if (show_progress) {
 668                         for (p = packed_git; p; p = p->next) {
 669                                 if (open_pack_index(p))
 670                                         continue;
 671                                 total += p->num_objects;
 672                         }
 673
 674                         progress = start_progress("Checking objects", total);
 675                 }
 676                 for (p = packed_git; p; p = p->next) {
 677                         /* verify gives error messages itself */
 678                         if (verify_pack(p, fsck_obj_buffer,
 679                                         progress, count))
 680                                 errors_found |= ERROR_PACK;
 681                         count += p->num_objects;
 682                 }
 683                 stop_progress(&progress);
 684         }
 685
 686         heads = 0;
 687         for (i = 0; i < argc; i++) {
 688                 const char *arg = argv[i];
 689                 unsigned char sha1[20];
 690                 if (!get_sha1(arg, sha1)) {
 691                         struct object *obj = lookup_object(sha1);
 692
 693                         /* Error is printed by lookup_object(). */
 694                         if (!obj)
 695                                 continue;
 696
 697                         obj->used = 1;
 698                         mark_object_reachable(obj);
 699                         heads++;
 700                         continue;
 701                 }
 702                 error("invalid parameter: expected sha1, got '%s'", arg);
 703         }
 704
 705         /*
 706          * If we've not been given any explicit head information, do the
 707          * default ones from .git/refs. We also consider the index file
 708          * in this case (ie this implies --cache).
 709          */
 710         if (!heads) {
 711                 get_default_heads();
 712                 keep_cache_objects = 1;
 713         }
 714
 715         if (keep_cache_objects) {
 716                 read_cache();
 717                 for (i = 0; i < active_nr; i++) {
 718                         unsigned int mode;
 719                         struct blob *blob;
 720                         struct object *obj;
 721
 722                         mode = active_cache[i]->ce_mode;
 723                         if (S_ISGITLINK(mode))
 724                                 continue;
 725                         blob = lookup_blob(active_cache[i]->sha1);
 726                         if (!blob)
 727                                 continue;
 728                         obj = &blob->object;
 729                         obj->used = 1;
 730                         mark_object_reachable(obj);
 731                 }
 732                 if (active_cache_tree)
 733                         fsck_cache_tree(active_cache_tree);
 734         }
 735
 736         check_connectivity();
 737         return errors_found;
 738 }