git.oblomov.eu Git - git/blob - builtin/fsck.c

   1 #define USE_THE_INDEX_COMPATIBILITY_MACROS
   2 #include "builtin.h"
   3 #include "cache.h"
   4 #include "repository.h"
   5 #include "config.h"
   6 #include "commit.h"
   7 #include "tree.h"
   8 #include "blob.h"
   9 #include "tag.h"
  10 #include "refs.h"
  11 #include "pack.h"
  12 #include "cache-tree.h"
  13 #include "tree-walk.h"
  14 #include "fsck.h"
  15 #include "parse-options.h"
  16 #include "dir.h"
  17 #include "progress.h"
  18 #include "streaming.h"
  19 #include "decorate.h"
  20 #include "packfile.h"
  21 #include "object-store.h"
  22 #include "run-command.h"
  23 #include "worktree.h"
  24
  25 #define REACHABLE 0x0001
  26 #define SEEN      0x0002
  27 #define HAS_OBJ   0x0004
  28 /* This flag is set if something points to this object. */
  29 #define USED      0x0008
  30
  31 static int show_root;
  32 static int show_tags;
  33 static int show_unreachable;
  34 static int include_reflogs = 1;
  35 static int check_full = 1;
  36 static int connectivity_only;
  37 static int check_strict;
  38 static int keep_cache_objects;
  39 static struct fsck_options fsck_walk_options = FSCK_OPTIONS_DEFAULT;
  40 static struct fsck_options fsck_obj_options = FSCK_OPTIONS_DEFAULT;
  41 static int errors_found;
  42 static int write_lost_and_found;
  43 static int verbose;
  44 static int show_progress = -1;
  45 static int show_dangling = 1;
  46 static int name_objects;
  47 #define ERROR_OBJECT 01
  48 #define ERROR_REACHABLE 02
  49 #define ERROR_PACK 04
  50 #define ERROR_REFS 010
  51 #define ERROR_COMMIT_GRAPH 020
  52 #define ERROR_MULTI_PACK_INDEX 040
  53
  54 static const char *describe_object(const struct object_id *oid)
  55 {
  56         return fsck_describe_object(&fsck_walk_options, oid);
  57 }
  58
  59 static const char *printable_type(const struct object_id *oid,
  60                                   enum object_type type)
  61 {
  62         const char *ret;
  63
  64         if (type == OBJ_NONE)
  65                 type = oid_object_info(the_repository, oid, NULL);
  66
  67         ret = type_name(type);
  68         if (!ret)
  69                 ret = _("unknown");
  70
  71         return ret;
  72 }
  73
  74 static int fsck_config(const char *var, const char *value, void *cb)
  75 {
  76         if (strcmp(var, "fsck.skiplist") == 0) {
  77                 const char *path;
  78                 struct strbuf sb = STRBUF_INIT;
  79
  80                 if (git_config_pathname(&path, var, value))
  81                         return 1;
  82                 strbuf_addf(&sb, "skiplist=%s", path);
  83                 free((char *)path);
  84                 fsck_set_msg_types(&fsck_obj_options, sb.buf);
  85                 strbuf_release(&sb);
  86                 return 0;
  87         }
  88
  89         if (skip_prefix(var, "fsck.", &var)) {
  90                 fsck_set_msg_type(&fsck_obj_options, var, value);
  91                 return 0;
  92         }
  93
  94         return git_default_config(var, value, cb);
  95 }
  96
  97 static int objerror(struct object *obj, const char *err)
  98 {
  99         errors_found |= ERROR_OBJECT;
 100         /* TRANSLATORS: e.g. error in tree 01bfda: <more explanation> */
 101         fprintf_ln(stderr, _("error in %s %s: %s"),
 102                    printable_type(&obj->oid, obj->type),
 103                    describe_object(&obj->oid), err);
 104         return -1;
 105 }
 106
 107 static int fsck_error_func(struct fsck_options *o,
 108                            const struct object_id *oid,
 109                            enum object_type object_type,
 110                            int msg_type, const char *message)
 111 {
 112         switch (msg_type) {
 113         case FSCK_WARN:
 114                 /* TRANSLATORS: e.g. warning in tree 01bfda: <more explanation> */
 115                 fprintf_ln(stderr, _("warning in %s %s: %s"),
 116                            printable_type(oid, object_type),
 117                            describe_object(oid), message);
 118                 return 0;
 119         case FSCK_ERROR:
 120                 /* TRANSLATORS: e.g. error in tree 01bfda: <more explanation> */
 121                 fprintf_ln(stderr, _("error in %s %s: %s"),
 122                            printable_type(oid, object_type),
 123                            describe_object(oid), message);
 124                 return 1;
 125         default:
 126                 BUG("%d (FSCK_IGNORE?) should never trigger this callback",
 127                     msg_type);
 128         }
 129 }
 130
 131 static struct object_array pending;
 132
 133 static int mark_object(struct object *obj, int type, void *data, struct fsck_options *options)
 134 {
 135         struct object *parent = data;
 136
 137         /*
 138          * The only case data is NULL or type is OBJ_ANY is when
 139          * mark_object_reachable() calls us.  All the callers of
 140          * that function has non-NULL obj hence ...
 141          */
 142         if (!obj) {
 143                 /* ... these references to parent->fld are safe here */
 144                 printf_ln(_("broken link from %7s %s"),
 145                           printable_type(&parent->oid, parent->type),
 146                           describe_object(&parent->oid));
 147                 printf_ln(_("broken link from %7s %s"),
 148                           (type == OBJ_ANY ? _("unknown") : type_name(type)),
 149                           _("unknown"));
 150                 errors_found |= ERROR_REACHABLE;
 151                 return 1;
 152         }
 153
 154         if (type != OBJ_ANY && obj->type != type)
 155                 /* ... and the reference to parent is safe here */
 156                 objerror(parent, _("wrong object type in link"));
 157
 158         if (obj->flags & REACHABLE)
 159                 return 0;
 160         obj->flags |= REACHABLE;
 161
 162         if (is_promisor_object(&obj->oid))
 163                 /*
 164                  * Further recursion does not need to be performed on this
 165                  * object since it is a promisor object (so it does not need to
 166                  * be added to "pending").
 167                  */
 168                 return 0;
 169
 170         if (!(obj->flags & HAS_OBJ)) {
 171                 if (parent && !has_object_file(&obj->oid)) {
 172                         printf_ln(_("broken link from %7s %s\n"
 173                                     "              to %7s %s"),
 174                                   printable_type(&parent->oid, parent->type),
 175                                   describe_object(&parent->oid),
 176                                   printable_type(&obj->oid, obj->type),
 177                                   describe_object(&obj->oid));
 178                         errors_found |= ERROR_REACHABLE;
 179                 }
 180                 return 1;
 181         }
 182
 183         add_object_array(obj, NULL, &pending);
 184         return 0;
 185 }
 186
 187 static void mark_object_reachable(struct object *obj)
 188 {
 189         mark_object(obj, OBJ_ANY, NULL, NULL);
 190 }
 191
 192 static int traverse_one_object(struct object *obj)
 193 {
 194         int result = fsck_walk(obj, obj, &fsck_walk_options);
 195
 196         if (obj->type == OBJ_TREE) {
 197                 struct tree *tree = (struct tree *)obj;
 198                 free_tree_buffer(tree);
 199         }
 200         return result;
 201 }
 202
 203 static int traverse_reachable(void)
 204 {
 205         struct progress *progress = NULL;
 206         unsigned int nr = 0;
 207         int result = 0;
 208         if (show_progress)
 209                 progress = start_delayed_progress(_("Checking connectivity"), 0);
 210         while (pending.nr) {
 211                 result |= traverse_one_object(object_array_pop(&pending));
 212                 display_progress(progress, ++nr);
 213         }
 214         stop_progress(&progress);
 215         return !!result;
 216 }
 217
 218 static int mark_used(struct object *obj, int type, void *data, struct fsck_options *options)
 219 {
 220         if (!obj)
 221                 return 1;
 222         obj->flags |= USED;
 223         return 0;
 224 }
 225
 226 static void mark_unreachable_referents(const struct object_id *oid)
 227 {
 228         struct fsck_options options = FSCK_OPTIONS_DEFAULT;
 229         struct object *obj = lookup_object(the_repository, oid);
 230
 231         if (!obj || !(obj->flags & HAS_OBJ))
 232                 return; /* not part of our original set */
 233         if (obj->flags & REACHABLE)
 234                 return; /* reachable objects already traversed */
 235
 236         /*
 237          * Avoid passing OBJ_NONE to fsck_walk, which will parse the object
 238          * (and we want to avoid parsing blobs).
 239          */
 240         if (obj->type == OBJ_NONE) {
 241                 enum object_type type = oid_object_info(the_repository,
 242                                                         &obj->oid, NULL);
 243                 if (type > 0)
 244                         object_as_type(the_repository, obj, type, 0);
 245         }
 246
 247         options.walk = mark_used;
 248         fsck_walk(obj, NULL, &options);
 249 }
 250
 251 static int mark_loose_unreachable_referents(const struct object_id *oid,
 252                                             const char *path,
 253                                             void *data)
 254 {
 255         mark_unreachable_referents(oid);
 256         return 0;
 257 }
 258
 259 static int mark_packed_unreachable_referents(const struct object_id *oid,
 260                                              struct packed_git *pack,
 261                                              uint32_t pos,
 262                                              void *data)
 263 {
 264         mark_unreachable_referents(oid);
 265         return 0;
 266 }
 267
 268 /*
 269  * Check a single reachable object
 270  */
 271 static void check_reachable_object(struct object *obj)
 272 {
 273         /*
 274          * We obviously want the object to be parsed,
 275          * except if it was in a pack-file and we didn't
 276          * do a full fsck
 277          */
 278         if (!(obj->flags & HAS_OBJ)) {
 279                 if (is_promisor_object(&obj->oid))
 280                         return;
 281                 if (has_object_pack(&obj->oid))
 282                         return; /* it is in pack - forget about it */
 283                 printf_ln(_("missing %s %s"),
 284                           printable_type(&obj->oid, obj->type),
 285                           describe_object(&obj->oid));
 286                 errors_found |= ERROR_REACHABLE;
 287                 return;
 288         }
 289 }
 290
 291 /*
 292  * Check a single unreachable object
 293  */
 294 static void check_unreachable_object(struct object *obj)
 295 {
 296         /*
 297          * Missing unreachable object? Ignore it. It's not like
 298          * we miss it (since it can't be reached), nor do we want
 299          * to complain about it being unreachable (since it does
 300          * not exist).
 301          */
 302         if (!(obj->flags & HAS_OBJ))
 303                 return;
 304
 305         /*
 306          * Unreachable object that exists? Show it if asked to,
 307          * since this is something that is prunable.
 308          */
 309         if (show_unreachable) {
 310                 printf_ln(_("unreachable %s %s"),
 311                           printable_type(&obj->oid, obj->type),
 312                           describe_object(&obj->oid));
 313                 return;
 314         }
 315
 316         /*
 317          * "!USED" means that nothing at all points to it, including
 318          * other unreachable objects. In other words, it's the "tip"
 319          * of some set of unreachable objects, usually a commit that
 320          * got dropped.
 321          *
 322          * Such starting points are more interesting than some random
 323          * set of unreachable objects, so we show them even if the user
 324          * hasn't asked for _all_ unreachable objects. If you have
 325          * deleted a branch by mistake, this is a prime candidate to
 326          * start looking at, for example.
 327          */
 328         if (!(obj->flags & USED)) {
 329                 if (show_dangling)
 330                         printf_ln(_("dangling %s %s"),
 331                                   printable_type(&obj->oid, obj->type),
 332                                   describe_object(&obj->oid));
 333                 if (write_lost_and_found) {
 334                         char *filename = git_pathdup("lost-found/%s/%s",
 335                                 obj->type == OBJ_COMMIT ? "commit" : "other",
 336                                 describe_object(&obj->oid));
 337                         FILE *f;
 338
 339                         if (safe_create_leading_directories_const(filename)) {
 340                                 error(_("could not create lost-found"));
 341                                 free(filename);
 342                                 return;
 343                         }
 344                         f = xfopen(filename, "w");
 345                         if (obj->type == OBJ_BLOB) {
 346                                 if (stream_blob_to_fd(fileno(f), &obj->oid, NULL, 1))
 347                                         die_errno(_("could not write '%s'"), filename);
 348                         } else
 349                                 fprintf(f, "%s\n", describe_object(&obj->oid));
 350                         if (fclose(f))
 351                                 die_errno(_("could not finish '%s'"),
 352                                           filename);
 353                         free(filename);
 354                 }
 355                 return;
 356         }
 357
 358         /*
 359          * Otherwise? It's there, it's unreachable, and some other unreachable
 360          * object points to it. Ignore it - it's not interesting, and we showed
 361          * all the interesting cases above.
 362          */
 363 }
 364
 365 static void check_object(struct object *obj)
 366 {
 367         if (verbose)
 368                 fprintf_ln(stderr, _("Checking %s"), describe_object(&obj->oid));
 369
 370         if (obj->flags & REACHABLE)
 371                 check_reachable_object(obj);
 372         else
 373                 check_unreachable_object(obj);
 374 }
 375
 376 static void check_connectivity(void)
 377 {
 378         int i, max;
 379
 380         /* Traverse the pending reachable objects */
 381         traverse_reachable();
 382
 383         /*
 384          * With --connectivity-only, we won't have actually opened and marked
 385          * unreachable objects with USED. Do that now to make --dangling, etc
 386          * accurate.
 387          */
 388         if (connectivity_only && (show_dangling || write_lost_and_found)) {
 389                 /*
 390                  * Even though we already have a "struct object" for each of
 391                  * these in memory, we must not iterate over the internal
 392                  * object hash as we do below. Our loop would potentially
 393                  * resize the hash, making our iteration invalid.
 394                  *
 395                  * Instead, we'll just go back to the source list of objects,
 396                  * and ignore any that weren't present in our earlier
 397                  * traversal.
 398                  */
 399                 for_each_loose_object(mark_loose_unreachable_referents, NULL, 0);
 400                 for_each_packed_object(mark_packed_unreachable_referents, NULL, 0);
 401         }
 402
 403         /* Look up all the requirements, warn about missing objects.. */
 404         max = get_max_object_index();
 405         if (verbose)
 406                 fprintf_ln(stderr, _("Checking connectivity (%d objects)"), max);
 407
 408         for (i = 0; i < max; i++) {
 409                 struct object *obj = get_indexed_object(i);
 410
 411                 if (obj)
 412                         check_object(obj);
 413         }
 414 }
 415
 416 static int fsck_obj(struct object *obj, void *buffer, unsigned long size)
 417 {
 418         int err;
 419
 420         if (obj->flags & SEEN)
 421                 return 0;
 422         obj->flags |= SEEN;
 423
 424         if (verbose)
 425                 fprintf_ln(stderr, _("Checking %s %s"),
 426                            printable_type(&obj->oid, obj->type),
 427                            describe_object(&obj->oid));
 428
 429         if (fsck_walk(obj, NULL, &fsck_obj_options))
 430                 objerror(obj, _("broken links"));
 431         err = fsck_object(obj, buffer, size, &fsck_obj_options);
 432         if (err)
 433                 goto out;
 434
 435         if (obj->type == OBJ_COMMIT) {
 436                 struct commit *commit = (struct commit *) obj;
 437
 438                 if (!commit->parents && show_root)
 439                         printf_ln(_("root %s"),
 440                                   describe_object(&commit->object.oid));
 441         }
 442
 443         if (obj->type == OBJ_TAG) {
 444                 struct tag *tag = (struct tag *) obj;
 445
 446                 if (show_tags && tag->tagged) {
 447                         printf_ln(_("tagged %s %s (%s) in %s"),
 448                                   printable_type(&tag->tagged->oid, tag->tagged->type),
 449                                   describe_object(&tag->tagged->oid),
 450                                   tag->tag,
 451                                   describe_object(&tag->object.oid));
 452                 }
 453         }
 454
 455 out:
 456         if (obj->type == OBJ_TREE)
 457                 free_tree_buffer((struct tree *)obj);
 458         if (obj->type == OBJ_COMMIT)
 459                 free_commit_buffer(the_repository->parsed_objects,
 460                                    (struct commit *)obj);
 461         return err;
 462 }
 463
 464 static int fsck_obj_buffer(const struct object_id *oid, enum object_type type,
 465                            unsigned long size, void *buffer, int *eaten)
 466 {
 467         /*
 468          * Note, buffer may be NULL if type is OBJ_BLOB. See
 469          * verify_packfile(), data_valid variable for details.
 470          */
 471         struct object *obj;
 472         obj = parse_object_buffer(the_repository, oid, type, size, buffer,
 473                                   eaten);
 474         if (!obj) {
 475                 errors_found |= ERROR_OBJECT;
 476                 return error(_("%s: object corrupt or missing"),
 477                              oid_to_hex(oid));
 478         }
 479         obj->flags &= ~(REACHABLE | SEEN);
 480         obj->flags |= HAS_OBJ;
 481         return fsck_obj(obj, buffer, size);
 482 }
 483
 484 static int default_refs;
 485
 486 static void fsck_handle_reflog_oid(const char *refname, struct object_id *oid,
 487         timestamp_t timestamp)
 488 {
 489         struct object *obj;
 490
 491         if (!is_null_oid(oid)) {
 492                 obj = lookup_object(the_repository, oid);
 493                 if (obj && (obj->flags & HAS_OBJ)) {
 494                         if (timestamp)
 495                                 fsck_put_object_name(&fsck_walk_options, oid,
 496                                                      "%s@{%"PRItime"}",
 497                                                      refname, timestamp);
 498                         obj->flags |= USED;
 499                         mark_object_reachable(obj);
 500                 } else if (!is_promisor_object(oid)) {
 501                         error(_("%s: invalid reflog entry %s"),
 502                               refname, oid_to_hex(oid));
 503                         errors_found |= ERROR_REACHABLE;
 504                 }
 505         }
 506 }
 507
 508 static int fsck_handle_reflog_ent(struct object_id *ooid, struct object_id *noid,
 509                 const char *email, timestamp_t timestamp, int tz,
 510                 const char *message, void *cb_data)
 511 {
 512         const char *refname = cb_data;
 513
 514         if (verbose)
 515                 fprintf_ln(stderr, _("Checking reflog %s->%s"),
 516                            oid_to_hex(ooid), oid_to_hex(noid));
 517
 518         fsck_handle_reflog_oid(refname, ooid, 0);
 519         fsck_handle_reflog_oid(refname, noid, timestamp);
 520         return 0;
 521 }
 522
 523 static int fsck_handle_reflog(const char *logname, const struct object_id *oid,
 524                               int flag, void *cb_data)
 525 {
 526         struct strbuf refname = STRBUF_INIT;
 527
 528         strbuf_worktree_ref(cb_data, &refname, logname);
 529         for_each_reflog_ent(refname.buf, fsck_handle_reflog_ent, refname.buf);
 530         strbuf_release(&refname);
 531         return 0;
 532 }
 533
 534 static int fsck_handle_ref(const char *refname, const struct object_id *oid,
 535                            int flag, void *cb_data)
 536 {
 537         struct object *obj;
 538
 539         obj = parse_object(the_repository, oid);
 540         if (!obj) {
 541                 if (is_promisor_object(oid)) {
 542                         /*
 543                          * Increment default_refs anyway, because this is a
 544                          * valid ref.
 545                          */
 546                          default_refs++;
 547                          return 0;
 548                 }
 549                 error(_("%s: invalid sha1 pointer %s"),
 550                       refname, oid_to_hex(oid));
 551                 errors_found |= ERROR_REACHABLE;
 552                 /* We'll continue with the rest despite the error.. */
 553                 return 0;
 554         }
 555         if (obj->type != OBJ_COMMIT && is_branch(refname)) {
 556                 error(_("%s: not a commit"), refname);
 557                 errors_found |= ERROR_REFS;
 558         }
 559         default_refs++;
 560         obj->flags |= USED;
 561         fsck_put_object_name(&fsck_walk_options,
 562                              oid, "%s", refname);
 563         mark_object_reachable(obj);
 564
 565         return 0;
 566 }
 567
 568 static int fsck_head_link(const char *head_ref_name,
 569                           const char **head_points_at,
 570                           struct object_id *head_oid);
 571
 572 static void get_default_heads(void)
 573 {
 574         struct worktree **worktrees, **p;
 575         const char *head_points_at;
 576         struct object_id head_oid;
 577
 578         for_each_rawref(fsck_handle_ref, NULL);
 579
 580         worktrees = get_worktrees(0);
 581         for (p = worktrees; *p; p++) {
 582                 struct worktree *wt = *p;
 583                 struct strbuf ref = STRBUF_INIT;
 584
 585                 strbuf_worktree_ref(wt, &ref, "HEAD");
 586                 fsck_head_link(ref.buf, &head_points_at, &head_oid);
 587                 if (head_points_at && !is_null_oid(&head_oid))
 588                         fsck_handle_ref(ref.buf, &head_oid, 0, NULL);
 589                 strbuf_release(&ref);
 590
 591                 if (include_reflogs)
 592                         refs_for_each_reflog(get_worktree_ref_store(wt),
 593                                              fsck_handle_reflog, wt);
 594         }
 595         free_worktrees(worktrees);
 596
 597         /*
 598          * Not having any default heads isn't really fatal, but
 599          * it does mean that "--unreachable" no longer makes any
 600          * sense (since in this case everything will obviously
 601          * be unreachable by definition.
 602          *
 603          * Showing dangling objects is valid, though (as those
 604          * dangling objects are likely lost heads).
 605          *
 606          * So we just print a warning about it, and clear the
 607          * "show_unreachable" flag.
 608          */
 609         if (!default_refs) {
 610                 fprintf_ln(stderr, _("notice: No default references"));
 611                 show_unreachable = 0;
 612         }
 613 }
 614
 615 static int fsck_loose(const struct object_id *oid, const char *path, void *data)
 616 {
 617         struct object *obj;
 618         enum object_type type;
 619         unsigned long size;
 620         void *contents;
 621         int eaten;
 622
 623         if (read_loose_object(path, oid, &type, &size, &contents) < 0) {
 624                 errors_found |= ERROR_OBJECT;
 625                 error(_("%s: object corrupt or missing: %s"),
 626                       oid_to_hex(oid), path);
 627                 return 0; /* keep checking other objects */
 628         }
 629
 630         if (!contents && type != OBJ_BLOB)
 631                 BUG("read_loose_object streamed a non-blob");
 632
 633         obj = parse_object_buffer(the_repository, oid, type, size,
 634                                   contents, &eaten);
 635
 636         if (!obj) {
 637                 errors_found |= ERROR_OBJECT;
 638                 error(_("%s: object could not be parsed: %s"),
 639                       oid_to_hex(oid), path);
 640                 if (!eaten)
 641                         free(contents);
 642                 return 0; /* keep checking other objects */
 643         }
 644
 645         obj->flags &= ~(REACHABLE | SEEN);
 646         obj->flags |= HAS_OBJ;
 647         if (fsck_obj(obj, contents, size))
 648                 errors_found |= ERROR_OBJECT;
 649
 650         if (!eaten)
 651                 free(contents);
 652         return 0; /* keep checking other objects, even if we saw an error */
 653 }
 654
 655 static int fsck_cruft(const char *basename, const char *path, void *data)
 656 {
 657         if (!starts_with(basename, "tmp_obj_"))
 658                 fprintf_ln(stderr, _("bad sha1 file: %s"), path);
 659         return 0;
 660 }
 661
 662 static int fsck_subdir(unsigned int nr, const char *path, void *progress)
 663 {
 664         display_progress(progress, nr + 1);
 665         return 0;
 666 }
 667
 668 static void fsck_object_dir(const char *path)
 669 {
 670         struct progress *progress = NULL;
 671
 672         if (verbose)
 673                 fprintf_ln(stderr, _("Checking object directory"));
 674
 675         if (show_progress)
 676                 progress = start_progress(_("Checking object directories"), 256);
 677
 678         for_each_loose_file_in_objdir(path, fsck_loose, fsck_cruft, fsck_subdir,
 679                                       progress);
 680         display_progress(progress, 256);
 681         stop_progress(&progress);
 682 }
 683
 684 static int fsck_head_link(const char *head_ref_name,
 685                           const char **head_points_at,
 686                           struct object_id *head_oid)
 687 {
 688         int null_is_error = 0;
 689
 690         if (verbose)
 691                 fprintf_ln(stderr, _("Checking %s link"), head_ref_name);
 692
 693         *head_points_at = resolve_ref_unsafe(head_ref_name, 0, head_oid, NULL);
 694         if (!*head_points_at) {
 695                 errors_found |= ERROR_REFS;
 696                 return error(_("invalid %s"), head_ref_name);
 697         }
 698         if (!strcmp(*head_points_at, head_ref_name))
 699                 /* detached HEAD */
 700                 null_is_error = 1;
 701         else if (!starts_with(*head_points_at, "refs/heads/")) {
 702                 errors_found |= ERROR_REFS;
 703                 return error(_("%s points to something strange (%s)"),
 704                              head_ref_name, *head_points_at);
 705         }
 706         if (is_null_oid(head_oid)) {
 707                 if (null_is_error) {
 708                         errors_found |= ERROR_REFS;
 709                         return error(_("%s: detached HEAD points at nothing"),
 710                                      head_ref_name);
 711                 }
 712                 fprintf_ln(stderr,
 713                            _("notice: %s points to an unborn branch (%s)"),
 714                            head_ref_name, *head_points_at + 11);
 715         }
 716         return 0;
 717 }
 718
 719 static int fsck_cache_tree(struct cache_tree *it)
 720 {
 721         int i;
 722         int err = 0;
 723
 724         if (verbose)
 725                 fprintf_ln(stderr, _("Checking cache tree"));
 726
 727         if (0 <= it->entry_count) {
 728                 struct object *obj = parse_object(the_repository, &it->oid);
 729                 if (!obj) {
 730                         error(_("%s: invalid sha1 pointer in cache-tree"),
 731                               oid_to_hex(&it->oid));
 732                         errors_found |= ERROR_REFS;
 733                         return 1;
 734                 }
 735                 obj->flags |= USED;
 736                 fsck_put_object_name(&fsck_walk_options, &it->oid, ":");
 737                 mark_object_reachable(obj);
 738                 if (obj->type != OBJ_TREE)
 739                         err |= objerror(obj, _("non-tree in cache-tree"));
 740         }
 741         for (i = 0; i < it->subtree_nr; i++)
 742                 err |= fsck_cache_tree(it->down[i]->cache_tree);
 743         return err;
 744 }
 745
 746 static void mark_object_for_connectivity(const struct object_id *oid)
 747 {
 748         struct object *obj = lookup_unknown_object(oid);
 749         obj->flags |= HAS_OBJ;
 750 }
 751
 752 static int mark_loose_for_connectivity(const struct object_id *oid,
 753                                        const char *path,
 754                                        void *data)
 755 {
 756         mark_object_for_connectivity(oid);
 757         return 0;
 758 }
 759
 760 static int mark_packed_for_connectivity(const struct object_id *oid,
 761                                         struct packed_git *pack,
 762                                         uint32_t pos,
 763                                         void *data)
 764 {
 765         mark_object_for_connectivity(oid);
 766         return 0;
 767 }
 768
 769 static char const * const fsck_usage[] = {
 770         N_("git fsck [<options>] [<object>...]"),
 771         NULL
 772 };
 773
 774 static struct option fsck_opts[] = {
 775         OPT__VERBOSE(&verbose, N_("be verbose")),
 776         OPT_BOOL(0, "unreachable", &show_unreachable, N_("show unreachable objects")),
 777         OPT_BOOL(0, "dangling", &show_dangling, N_("show dangling objects")),
 778         OPT_BOOL(0, "tags", &show_tags, N_("report tags")),
 779         OPT_BOOL(0, "root", &show_root, N_("report root nodes")),
 780         OPT_BOOL(0, "cache", &keep_cache_objects, N_("make index objects head nodes")),
 781         OPT_BOOL(0, "reflogs", &include_reflogs, N_("make reflogs head nodes (default)")),
 782         OPT_BOOL(0, "full", &check_full, N_("also consider packs and alternate objects")),
 783         OPT_BOOL(0, "connectivity-only", &connectivity_only, N_("check only connectivity")),
 784         OPT_BOOL(0, "strict", &check_strict, N_("enable more strict checking")),
 785         OPT_BOOL(0, "lost-found", &write_lost_and_found,
 786                                 N_("write dangling objects in .git/lost-found")),
 787         OPT_BOOL(0, "progress", &show_progress, N_("show progress")),
 788         OPT_BOOL(0, "name-objects", &name_objects, N_("show verbose names for reachable objects")),
 789         OPT_END(),
 790 };
 791
 792 int cmd_fsck(int argc, const char **argv, const char *prefix)
 793 {
 794         int i;
 795         struct object_directory *odb;
 796
 797         /* fsck knows how to handle missing promisor objects */
 798         fetch_if_missing = 0;
 799
 800         errors_found = 0;
 801         read_replace_refs = 0;
 802
 803         argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0);
 804
 805         fsck_walk_options.walk = mark_object;
 806         fsck_obj_options.walk = mark_used;
 807         fsck_obj_options.error_func = fsck_error_func;
 808         if (check_strict)
 809                 fsck_obj_options.strict = 1;
 810
 811         if (show_progress == -1)
 812                 show_progress = isatty(2);
 813         if (verbose)
 814                 show_progress = 0;
 815
 816         if (write_lost_and_found) {
 817                 check_full = 1;
 818                 include_reflogs = 0;
 819         }
 820
 821         if (name_objects)
 822                 fsck_enable_object_names(&fsck_walk_options);
 823
 824         git_config(fsck_config, NULL);
 825
 826         if (connectivity_only) {
 827                 for_each_loose_object(mark_loose_for_connectivity, NULL, 0);
 828                 for_each_packed_object(mark_packed_for_connectivity, NULL, 0);
 829         } else {
 830                 prepare_alt_odb(the_repository);
 831                 for (odb = the_repository->objects->odb; odb; odb = odb->next)
 832                         fsck_object_dir(odb->path);
 833
 834                 if (check_full) {
 835                         struct packed_git *p;
 836                         uint32_t total = 0, count = 0;
 837                         struct progress *progress = NULL;
 838
 839                         if (show_progress) {
 840                                 for (p = get_all_packs(the_repository); p;
 841                                      p = p->next) {
 842                                         if (open_pack_index(p))
 843                                                 continue;
 844                                         total += p->num_objects;
 845                                 }
 846
 847                                 progress = start_progress(_("Checking objects"), total);
 848                         }
 849                         for (p = get_all_packs(the_repository); p;
 850                              p = p->next) {
 851                                 /* verify gives error messages itself */
 852                                 if (verify_pack(the_repository,
 853                                                 p, fsck_obj_buffer,
 854                                                 progress, count))
 855                                         errors_found |= ERROR_PACK;
 856                                 count += p->num_objects;
 857                         }
 858                         stop_progress(&progress);
 859                 }
 860
 861                 if (fsck_finish(&fsck_obj_options))
 862                         errors_found |= ERROR_OBJECT;
 863         }
 864
 865         for (i = 0; i < argc; i++) {
 866                 const char *arg = argv[i];
 867                 struct object_id oid;
 868                 if (!get_oid(arg, &oid)) {
 869                         struct object *obj = lookup_object(the_repository,
 870                                                            &oid);
 871
 872                         if (!obj || !(obj->flags & HAS_OBJ)) {
 873                                 if (is_promisor_object(&oid))
 874                                         continue;
 875                                 error(_("%s: object missing"), oid_to_hex(&oid));
 876                                 errors_found |= ERROR_OBJECT;
 877                                 continue;
 878                         }
 879
 880                         obj->flags |= USED;
 881                         fsck_put_object_name(&fsck_walk_options, &oid,
 882                                              "%s", arg);
 883                         mark_object_reachable(obj);
 884                         continue;
 885                 }
 886                 error(_("invalid parameter: expected sha1, got '%s'"), arg);
 887                 errors_found |= ERROR_OBJECT;
 888         }
 889
 890         /*
 891          * If we've not been given any explicit head information, do the
 892          * default ones from .git/refs. We also consider the index file
 893          * in this case (ie this implies --cache).
 894          */
 895         if (!argc) {
 896                 get_default_heads();
 897                 keep_cache_objects = 1;
 898         }
 899
 900         if (keep_cache_objects) {
 901                 verify_index_checksum = 1;
 902                 verify_ce_order = 1;
 903                 read_cache();
 904                 for (i = 0; i < active_nr; i++) {
 905                         unsigned int mode;
 906                         struct blob *blob;
 907                         struct object *obj;
 908
 909                         mode = active_cache[i]->ce_mode;
 910                         if (S_ISGITLINK(mode))
 911                                 continue;
 912                         blob = lookup_blob(the_repository,
 913                                            &active_cache[i]->oid);
 914                         if (!blob)
 915                                 continue;
 916                         obj = &blob->object;
 917                         obj->flags |= USED;
 918                         fsck_put_object_name(&fsck_walk_options, &obj->oid,
 919                                              ":%s", active_cache[i]->name);
 920                         mark_object_reachable(obj);
 921                 }
 922                 if (active_cache_tree)
 923                         fsck_cache_tree(active_cache_tree);
 924         }
 925
 926         check_connectivity();
 927
 928         if (!git_config_get_bool("core.commitgraph", &i) && i) {
 929                 struct child_process commit_graph_verify = CHILD_PROCESS_INIT;
 930                 const char *verify_argv[] = { "commit-graph", "verify", NULL, NULL, NULL };
 931
 932                 prepare_alt_odb(the_repository);
 933                 for (odb = the_repository->objects->odb; odb; odb = odb->next) {
 934                         child_process_init(&commit_graph_verify);
 935                         commit_graph_verify.argv = verify_argv;
 936                         commit_graph_verify.git_cmd = 1;
 937                         verify_argv[2] = "--object-dir";
 938                         verify_argv[3] = odb->path;
 939                         if (run_command(&commit_graph_verify))
 940                                 errors_found |= ERROR_COMMIT_GRAPH;
 941                 }
 942         }
 943
 944         if (!git_config_get_bool("core.multipackindex", &i) && i) {
 945                 struct child_process midx_verify = CHILD_PROCESS_INIT;
 946                 const char *midx_argv[] = { "multi-pack-index", "verify", NULL, NULL, NULL };
 947
 948                 prepare_alt_odb(the_repository);
 949                 for (odb = the_repository->objects->odb; odb; odb = odb->next) {
 950                         child_process_init(&midx_verify);
 951                         midx_verify.argv = midx_argv;
 952                         midx_verify.git_cmd = 1;
 953                         midx_argv[2] = "--object-dir";
 954                         midx_argv[3] = odb->path;
 955                         if (run_command(&midx_verify))
 956                                 errors_found |= ERROR_MULTI_PACK_INDEX;
 957                 }
 958         }
 959
 960         return errors_found;
 961 }