builtin / fsck.con commit Merge branch 'ab/doc-replace-gmane-links' (e4b6ccd)
   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#include "decorate.h"
  17
  18#define REACHABLE 0x0001
  19#define SEEN      0x0002
  20#define HAS_OBJ   0x0004
  21
  22static int show_root;
  23static int show_tags;
  24static int show_unreachable;
  25static int include_reflogs = 1;
  26static int check_full = 1;
  27static int connectivity_only;
  28static int check_strict;
  29static int keep_cache_objects;
  30static struct fsck_options fsck_walk_options = FSCK_OPTIONS_DEFAULT;
  31static struct fsck_options fsck_obj_options = FSCK_OPTIONS_DEFAULT;
  32static struct object_id head_oid;
  33static const char *head_points_at;
  34static int errors_found;
  35static int write_lost_and_found;
  36static int verbose;
  37static int show_progress = -1;
  38static int show_dangling = 1;
  39static int name_objects;
  40#define ERROR_OBJECT 01
  41#define ERROR_REACHABLE 02
  42#define ERROR_PACK 04
  43#define ERROR_REFS 010
  44
  45static const char *describe_object(struct object *obj)
  46{
  47        static struct strbuf buf = STRBUF_INIT;
  48        char *name = name_objects ?
  49                lookup_decoration(fsck_walk_options.object_names, obj) : NULL;
  50
  51        strbuf_reset(&buf);
  52        strbuf_addstr(&buf, oid_to_hex(&obj->oid));
  53        if (name)
  54                strbuf_addf(&buf, " (%s)", name);
  55
  56        return buf.buf;
  57}
  58
  59static const char *printable_type(struct object *obj)
  60{
  61        const char *ret;
  62
  63        if (obj->type == OBJ_NONE) {
  64                enum object_type type = sha1_object_info(obj->oid.hash, NULL);
  65                if (type > 0)
  66                        object_as_type(obj, type, 0);
  67        }
  68
  69        ret = typename(obj->type);
  70        if (!ret)
  71                ret = "unknown";
  72
  73        return ret;
  74}
  75
  76static int fsck_config(const char *var, const char *value, void *cb)
  77{
  78        if (strcmp(var, "fsck.skiplist") == 0) {
  79                const char *path;
  80                struct strbuf sb = STRBUF_INIT;
  81
  82                if (git_config_pathname(&path, var, value))
  83                        return 1;
  84                strbuf_addf(&sb, "skiplist=%s", path);
  85                free((char *)path);
  86                fsck_set_msg_types(&fsck_obj_options, sb.buf);
  87                strbuf_release(&sb);
  88                return 0;
  89        }
  90
  91        if (skip_prefix(var, "fsck.", &var)) {
  92                fsck_set_msg_type(&fsck_obj_options, var, value);
  93                return 0;
  94        }
  95
  96        return git_default_config(var, value, cb);
  97}
  98
  99static void objreport(struct object *obj, const char *msg_type,
 100                        const char *err)
 101{
 102        fprintf(stderr, "%s in %s %s: %s\n",
 103                msg_type, printable_type(obj), describe_object(obj), err);
 104}
 105
 106static int objerror(struct object *obj, const char *err)
 107{
 108        errors_found |= ERROR_OBJECT;
 109        objreport(obj, "error", err);
 110        return -1;
 111}
 112
 113static int fsck_error_func(struct fsck_options *o,
 114        struct object *obj, int type, const char *message)
 115{
 116        objreport(obj, (type == FSCK_WARN) ? "warning" : "error", message);
 117        return (type == FSCK_WARN) ? 0 : 1;
 118}
 119
 120static struct object_array pending;
 121
 122static int mark_object(struct object *obj, int type, void *data, struct fsck_options *options)
 123{
 124        struct object *parent = data;
 125
 126        /*
 127         * The only case data is NULL or type is OBJ_ANY is when
 128         * mark_object_reachable() calls us.  All the callers of
 129         * that function has non-NULL obj hence ...
 130         */
 131        if (!obj) {
 132                /* ... these references to parent->fld are safe here */
 133                printf("broken link from %7s %s\n",
 134                           printable_type(parent), describe_object(parent));
 135                printf("broken link from %7s %s\n",
 136                           (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
 137                errors_found |= ERROR_REACHABLE;
 138                return 1;
 139        }
 140
 141        if (type != OBJ_ANY && obj->type != type)
 142                /* ... and the reference to parent is safe here */
 143                objerror(parent, "wrong object type in link");
 144
 145        if (obj->flags & REACHABLE)
 146                return 0;
 147        obj->flags |= REACHABLE;
 148        if (!(obj->flags & HAS_OBJ)) {
 149                if (parent && !has_object_file(&obj->oid)) {
 150                        printf("broken link from %7s %s\n",
 151                                 printable_type(parent), describe_object(parent));
 152                        printf("              to %7s %s\n",
 153                                 printable_type(obj), describe_object(obj));
 154                        errors_found |= ERROR_REACHABLE;
 155                }
 156                return 1;
 157        }
 158
 159        add_object_array(obj, NULL, &pending);
 160        return 0;
 161}
 162
 163static void mark_object_reachable(struct object *obj)
 164{
 165        mark_object(obj, OBJ_ANY, NULL, NULL);
 166}
 167
 168static int traverse_one_object(struct object *obj)
 169{
 170        int result;
 171        struct tree *tree = NULL;
 172
 173        if (obj->type == OBJ_TREE) {
 174                tree = (struct tree *)obj;
 175                if (parse_tree(tree) < 0)
 176                        return 1; /* error already displayed */
 177        }
 178        result = fsck_walk(obj, obj, &fsck_walk_options);
 179        if (tree)
 180                free_tree_buffer(tree);
 181        return result;
 182}
 183
 184static int traverse_reachable(void)
 185{
 186        struct progress *progress = NULL;
 187        unsigned int nr = 0;
 188        int result = 0;
 189        if (show_progress)
 190                progress = start_progress_delay(_("Checking connectivity"), 0, 0, 2);
 191        while (pending.nr) {
 192                struct object_array_entry *entry;
 193                struct object *obj;
 194
 195                entry = pending.objects + --pending.nr;
 196                obj = entry->item;
 197                result |= traverse_one_object(obj);
 198                display_progress(progress, ++nr);
 199        }
 200        stop_progress(&progress);
 201        return !!result;
 202}
 203
 204static int mark_used(struct object *obj, int type, void *data, struct fsck_options *options)
 205{
 206        if (!obj)
 207                return 1;
 208        obj->used = 1;
 209        return 0;
 210}
 211
 212/*
 213 * Check a single reachable object
 214 */
 215static void check_reachable_object(struct object *obj)
 216{
 217        /*
 218         * We obviously want the object to be parsed,
 219         * except if it was in a pack-file and we didn't
 220         * do a full fsck
 221         */
 222        if (!(obj->flags & HAS_OBJ)) {
 223                if (has_sha1_pack(obj->oid.hash))
 224                        return; /* it is in pack - forget about it */
 225                printf("missing %s %s\n", printable_type(obj),
 226                        describe_object(obj));
 227                errors_found |= ERROR_REACHABLE;
 228                return;
 229        }
 230}
 231
 232/*
 233 * Check a single unreachable object
 234 */
 235static void check_unreachable_object(struct object *obj)
 236{
 237        /*
 238         * Missing unreachable object? Ignore it. It's not like
 239         * we miss it (since it can't be reached), nor do we want
 240         * to complain about it being unreachable (since it does
 241         * not exist).
 242         */
 243        if (!(obj->flags & HAS_OBJ))
 244                return;
 245
 246        /*
 247         * Unreachable object that exists? Show it if asked to,
 248         * since this is something that is prunable.
 249         */
 250        if (show_unreachable) {
 251                printf("unreachable %s %s\n", printable_type(obj),
 252                        describe_object(obj));
 253                return;
 254        }
 255
 256        /*
 257         * "!used" means that nothing at all points to it, including
 258         * other unreachable objects. In other words, it's the "tip"
 259         * of some set of unreachable objects, usually a commit that
 260         * got dropped.
 261         *
 262         * Such starting points are more interesting than some random
 263         * set of unreachable objects, so we show them even if the user
 264         * hasn't asked for _all_ unreachable objects. If you have
 265         * deleted a branch by mistake, this is a prime candidate to
 266         * start looking at, for example.
 267         */
 268        if (!obj->used) {
 269                if (show_dangling)
 270                        printf("dangling %s %s\n", printable_type(obj),
 271                               describe_object(obj));
 272                if (write_lost_and_found) {
 273                        char *filename = git_pathdup("lost-found/%s/%s",
 274                                obj->type == OBJ_COMMIT ? "commit" : "other",
 275                                describe_object(obj));
 276                        FILE *f;
 277
 278                        if (safe_create_leading_directories_const(filename)) {
 279                                error("Could not create lost-found");
 280                                free(filename);
 281                                return;
 282                        }
 283                        if (!(f = fopen(filename, "w")))
 284                                die_errno("Could not open '%s'", filename);
 285                        if (obj->type == OBJ_BLOB) {
 286                                if (stream_blob_to_fd(fileno(f), &obj->oid, NULL, 1))
 287                                        die_errno("Could not write '%s'", filename);
 288                        } else
 289                                fprintf(f, "%s\n", describe_object(obj));
 290                        if (fclose(f))
 291                                die_errno("Could not finish '%s'",
 292                                          filename);
 293                        free(filename);
 294                }
 295                return;
 296        }
 297
 298        /*
 299         * Otherwise? It's there, it's unreachable, and some other unreachable
 300         * object points to it. Ignore it - it's not interesting, and we showed
 301         * all the interesting cases above.
 302         */
 303}
 304
 305static void check_object(struct object *obj)
 306{
 307        if (verbose)
 308                fprintf(stderr, "Checking %s\n", describe_object(obj));
 309
 310        if (obj->flags & REACHABLE)
 311                check_reachable_object(obj);
 312        else
 313                check_unreachable_object(obj);
 314}
 315
 316static void check_connectivity(void)
 317{
 318        int i, max;
 319
 320        /* Traverse the pending reachable objects */
 321        traverse_reachable();
 322
 323        /* Look up all the requirements, warn about missing objects.. */
 324        max = get_max_object_index();
 325        if (verbose)
 326                fprintf(stderr, "Checking connectivity (%d objects)\n", max);
 327
 328        for (i = 0; i < max; i++) {
 329                struct object *obj = get_indexed_object(i);
 330
 331                if (obj)
 332                        check_object(obj);
 333        }
 334}
 335
 336static int fsck_obj(struct object *obj)
 337{
 338        if (obj->flags & SEEN)
 339                return 0;
 340        obj->flags |= SEEN;
 341
 342        if (verbose)
 343                fprintf(stderr, "Checking %s %s\n",
 344                        printable_type(obj), describe_object(obj));
 345
 346        if (fsck_walk(obj, NULL, &fsck_obj_options))
 347                objerror(obj, "broken links");
 348        if (fsck_object(obj, NULL, 0, &fsck_obj_options))
 349                return -1;
 350
 351        if (obj->type == OBJ_TREE) {
 352                struct tree *item = (struct tree *) obj;
 353
 354                free_tree_buffer(item);
 355        }
 356
 357        if (obj->type == OBJ_COMMIT) {
 358                struct commit *commit = (struct commit *) obj;
 359
 360                free_commit_buffer(commit);
 361
 362                if (!commit->parents && show_root)
 363                        printf("root %s\n", describe_object(&commit->object));
 364        }
 365
 366        if (obj->type == OBJ_TAG) {
 367                struct tag *tag = (struct tag *) obj;
 368
 369                if (show_tags && tag->tagged) {
 370                        printf("tagged %s %s", printable_type(tag->tagged),
 371                                describe_object(tag->tagged));
 372                        printf(" (%s) in %s\n", tag->tag,
 373                                describe_object(&tag->object));
 374                }
 375        }
 376
 377        return 0;
 378}
 379
 380static int fsck_obj_buffer(const unsigned char *sha1, enum object_type type,
 381                           unsigned long size, void *buffer, int *eaten)
 382{
 383        /*
 384         * Note, buffer may be NULL if type is OBJ_BLOB. See
 385         * verify_packfile(), data_valid variable for details.
 386         */
 387        struct object *obj;
 388        obj = parse_object_buffer(sha1, type, size, buffer, eaten);
 389        if (!obj) {
 390                errors_found |= ERROR_OBJECT;
 391                return error("%s: object corrupt or missing", sha1_to_hex(sha1));
 392        }
 393        obj->flags = HAS_OBJ;
 394        return fsck_obj(obj);
 395}
 396
 397static int default_refs;
 398
 399static void fsck_handle_reflog_oid(const char *refname, struct object_id *oid,
 400        timestamp_t timestamp)
 401{
 402        struct object *obj;
 403
 404        if (!is_null_oid(oid)) {
 405                obj = lookup_object(oid->hash);
 406                if (obj && (obj->flags & HAS_OBJ)) {
 407                        if (timestamp && name_objects)
 408                                add_decoration(fsck_walk_options.object_names,
 409                                        obj,
 410                                        xstrfmt("%s@{%"PRItime"}", refname, timestamp));
 411                        obj->used = 1;
 412                        mark_object_reachable(obj);
 413                } else {
 414                        error("%s: invalid reflog entry %s", refname, oid_to_hex(oid));
 415                        errors_found |= ERROR_REACHABLE;
 416                }
 417        }
 418}
 419
 420static int fsck_handle_reflog_ent(struct object_id *ooid, struct object_id *noid,
 421                const char *email, timestamp_t timestamp, int tz,
 422                const char *message, void *cb_data)
 423{
 424        const char *refname = cb_data;
 425
 426        if (verbose)
 427                fprintf(stderr, "Checking reflog %s->%s\n",
 428                        oid_to_hex(ooid), oid_to_hex(noid));
 429
 430        fsck_handle_reflog_oid(refname, ooid, 0);
 431        fsck_handle_reflog_oid(refname, noid, timestamp);
 432        return 0;
 433}
 434
 435static int fsck_handle_reflog(const char *logname, const struct object_id *oid,
 436                              int flag, void *cb_data)
 437{
 438        for_each_reflog_ent(logname, fsck_handle_reflog_ent, (void *)logname);
 439        return 0;
 440}
 441
 442static int fsck_handle_ref(const char *refname, const struct object_id *oid,
 443                           int flag, void *cb_data)
 444{
 445        struct object *obj;
 446
 447        obj = parse_object(oid->hash);
 448        if (!obj) {
 449                error("%s: invalid sha1 pointer %s", refname, oid_to_hex(oid));
 450                errors_found |= ERROR_REACHABLE;
 451                /* We'll continue with the rest despite the error.. */
 452                return 0;
 453        }
 454        if (obj->type != OBJ_COMMIT && is_branch(refname)) {
 455                error("%s: not a commit", refname);
 456                errors_found |= ERROR_REFS;
 457        }
 458        default_refs++;
 459        obj->used = 1;
 460        if (name_objects)
 461                add_decoration(fsck_walk_options.object_names,
 462                        obj, xstrdup(refname));
 463        mark_object_reachable(obj);
 464
 465        return 0;
 466}
 467
 468static void get_default_heads(void)
 469{
 470        if (head_points_at && !is_null_oid(&head_oid))
 471                fsck_handle_ref("HEAD", &head_oid, 0, NULL);
 472        for_each_rawref(fsck_handle_ref, NULL);
 473        if (include_reflogs)
 474                for_each_reflog(fsck_handle_reflog, NULL);
 475
 476        /*
 477         * Not having any default heads isn't really fatal, but
 478         * it does mean that "--unreachable" no longer makes any
 479         * sense (since in this case everything will obviously
 480         * be unreachable by definition.
 481         *
 482         * Showing dangling objects is valid, though (as those
 483         * dangling objects are likely lost heads).
 484         *
 485         * So we just print a warning about it, and clear the
 486         * "show_unreachable" flag.
 487         */
 488        if (!default_refs) {
 489                fprintf(stderr, "notice: No default references\n");
 490                show_unreachable = 0;
 491        }
 492}
 493
 494static struct object *parse_loose_object(const struct object_id *oid,
 495                                         const char *path)
 496{
 497        struct object *obj;
 498        void *contents;
 499        enum object_type type;
 500        unsigned long size;
 501        int eaten;
 502
 503        if (read_loose_object(path, oid->hash, &type, &size, &contents) < 0)
 504                return NULL;
 505
 506        if (!contents && type != OBJ_BLOB)
 507                die("BUG: read_loose_object streamed a non-blob");
 508
 509        obj = parse_object_buffer(oid->hash, type, size, contents, &eaten);
 510
 511        if (!eaten)
 512                free(contents);
 513        return obj;
 514}
 515
 516static int fsck_loose(const struct object_id *oid, const char *path, void *data)
 517{
 518        struct object *obj = parse_loose_object(oid, path);
 519
 520        if (!obj) {
 521                errors_found |= ERROR_OBJECT;
 522                error("%s: object corrupt or missing: %s",
 523                      oid_to_hex(oid), path);
 524                return 0; /* keep checking other objects */
 525        }
 526
 527        obj->flags = HAS_OBJ;
 528        if (fsck_obj(obj))
 529                errors_found |= ERROR_OBJECT;
 530        return 0;
 531}
 532
 533static int fsck_cruft(const char *basename, const char *path, void *data)
 534{
 535        if (!starts_with(basename, "tmp_obj_"))
 536                fprintf(stderr, "bad sha1 file: %s\n", path);
 537        return 0;
 538}
 539
 540static int fsck_subdir(int nr, const char *path, void *progress)
 541{
 542        display_progress(progress, nr + 1);
 543        return 0;
 544}
 545
 546static void fsck_object_dir(const char *path)
 547{
 548        struct progress *progress = NULL;
 549
 550        if (verbose)
 551                fprintf(stderr, "Checking object directory\n");
 552
 553        if (show_progress)
 554                progress = start_progress(_("Checking object directories"), 256);
 555
 556        for_each_loose_file_in_objdir(path, fsck_loose, fsck_cruft, fsck_subdir,
 557                                      progress);
 558        display_progress(progress, 256);
 559        stop_progress(&progress);
 560}
 561
 562static int fsck_head_link(void)
 563{
 564        int null_is_error = 0;
 565
 566        if (verbose)
 567                fprintf(stderr, "Checking HEAD link\n");
 568
 569        head_points_at = resolve_ref_unsafe("HEAD", 0, head_oid.hash, NULL);
 570        if (!head_points_at) {
 571                errors_found |= ERROR_REFS;
 572                return error("Invalid HEAD");
 573        }
 574        if (!strcmp(head_points_at, "HEAD"))
 575                /* detached HEAD */
 576                null_is_error = 1;
 577        else if (!starts_with(head_points_at, "refs/heads/")) {
 578                errors_found |= ERROR_REFS;
 579                return error("HEAD points to something strange (%s)",
 580                             head_points_at);
 581        }
 582        if (is_null_oid(&head_oid)) {
 583                if (null_is_error) {
 584                        errors_found |= ERROR_REFS;
 585                        return error("HEAD: detached HEAD points at nothing");
 586                }
 587                fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
 588                        head_points_at + 11);
 589        }
 590        return 0;
 591}
 592
 593static int fsck_cache_tree(struct cache_tree *it)
 594{
 595        int i;
 596        int err = 0;
 597
 598        if (verbose)
 599                fprintf(stderr, "Checking cache tree\n");
 600
 601        if (0 <= it->entry_count) {
 602                struct object *obj = parse_object(it->sha1);
 603                if (!obj) {
 604                        error("%s: invalid sha1 pointer in cache-tree",
 605                              sha1_to_hex(it->sha1));
 606                        errors_found |= ERROR_REFS;
 607                        return 1;
 608                }
 609                obj->used = 1;
 610                if (name_objects)
 611                        add_decoration(fsck_walk_options.object_names,
 612                                obj, xstrdup(":"));
 613                mark_object_reachable(obj);
 614                if (obj->type != OBJ_TREE)
 615                        err |= objerror(obj, "non-tree in cache-tree");
 616        }
 617        for (i = 0; i < it->subtree_nr; i++)
 618                err |= fsck_cache_tree(it->down[i]->cache_tree);
 619        return err;
 620}
 621
 622static void mark_object_for_connectivity(const struct object_id *oid)
 623{
 624        struct object *obj = lookup_unknown_object(oid->hash);
 625        obj->flags |= HAS_OBJ;
 626}
 627
 628static int mark_loose_for_connectivity(const struct object_id *oid,
 629                                       const char *path,
 630                                       void *data)
 631{
 632        mark_object_for_connectivity(oid);
 633        return 0;
 634}
 635
 636static int mark_packed_for_connectivity(const struct object_id *oid,
 637                                        struct packed_git *pack,
 638                                        uint32_t pos,
 639                                        void *data)
 640{
 641        mark_object_for_connectivity(oid);
 642        return 0;
 643}
 644
 645static char const * const fsck_usage[] = {
 646        N_("git fsck [<options>] [<object>...]"),
 647        NULL
 648};
 649
 650static struct option fsck_opts[] = {
 651        OPT__VERBOSE(&verbose, N_("be verbose")),
 652        OPT_BOOL(0, "unreachable", &show_unreachable, N_("show unreachable objects")),
 653        OPT_BOOL(0, "dangling", &show_dangling, N_("show dangling objects")),
 654        OPT_BOOL(0, "tags", &show_tags, N_("report tags")),
 655        OPT_BOOL(0, "root", &show_root, N_("report root nodes")),
 656        OPT_BOOL(0, "cache", &keep_cache_objects, N_("make index objects head nodes")),
 657        OPT_BOOL(0, "reflogs", &include_reflogs, N_("make reflogs head nodes (default)")),
 658        OPT_BOOL(0, "full", &check_full, N_("also consider packs and alternate objects")),
 659        OPT_BOOL(0, "connectivity-only", &connectivity_only, N_("check only connectivity")),
 660        OPT_BOOL(0, "strict", &check_strict, N_("enable more strict checking")),
 661        OPT_BOOL(0, "lost-found", &write_lost_and_found,
 662                                N_("write dangling objects in .git/lost-found")),
 663        OPT_BOOL(0, "progress", &show_progress, N_("show progress")),
 664        OPT_BOOL(0, "name-objects", &name_objects, N_("show verbose names for reachable objects")),
 665        OPT_END(),
 666};
 667
 668int cmd_fsck(int argc, const char **argv, const char *prefix)
 669{
 670        int i, heads;
 671        struct alternate_object_database *alt;
 672
 673        errors_found = 0;
 674        check_replace_refs = 0;
 675
 676        argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0);
 677
 678        fsck_walk_options.walk = mark_object;
 679        fsck_obj_options.walk = mark_used;
 680        fsck_obj_options.error_func = fsck_error_func;
 681        if (check_strict)
 682                fsck_obj_options.strict = 1;
 683
 684        if (show_progress == -1)
 685                show_progress = isatty(2);
 686        if (verbose)
 687                show_progress = 0;
 688
 689        if (write_lost_and_found) {
 690                check_full = 1;
 691                include_reflogs = 0;
 692        }
 693
 694        if (name_objects)
 695                fsck_walk_options.object_names =
 696                        xcalloc(1, sizeof(struct decoration));
 697
 698        git_config(fsck_config, NULL);
 699
 700        fsck_head_link();
 701        if (connectivity_only) {
 702                for_each_loose_object(mark_loose_for_connectivity, NULL, 0);
 703                for_each_packed_object(mark_packed_for_connectivity, NULL, 0);
 704        } else {
 705                fsck_object_dir(get_object_directory());
 706
 707                prepare_alt_odb();
 708                for (alt = alt_odb_list; alt; alt = alt->next)
 709                        fsck_object_dir(alt->path);
 710
 711                if (check_full) {
 712                        struct packed_git *p;
 713                        uint32_t total = 0, count = 0;
 714                        struct progress *progress = NULL;
 715
 716                        prepare_packed_git();
 717
 718                        if (show_progress) {
 719                                for (p = packed_git; p; p = p->next) {
 720                                        if (open_pack_index(p))
 721                                                continue;
 722                                        total += p->num_objects;
 723                                }
 724
 725                                progress = start_progress(_("Checking objects"), total);
 726                        }
 727                        for (p = packed_git; p; p = p->next) {
 728                                /* verify gives error messages itself */
 729                                if (verify_pack(p, fsck_obj_buffer,
 730                                                progress, count))
 731                                        errors_found |= ERROR_PACK;
 732                                count += p->num_objects;
 733                        }
 734                        stop_progress(&progress);
 735                }
 736        }
 737
 738        heads = 0;
 739        for (i = 0; i < argc; i++) {
 740                const char *arg = argv[i];
 741                unsigned char sha1[20];
 742                if (!get_sha1(arg, sha1)) {
 743                        struct object *obj = lookup_object(sha1);
 744
 745                        if (!obj || !(obj->flags & HAS_OBJ)) {
 746                                error("%s: object missing", sha1_to_hex(sha1));
 747                                errors_found |= ERROR_OBJECT;
 748                                continue;
 749                        }
 750
 751                        obj->used = 1;
 752                        if (name_objects)
 753                                add_decoration(fsck_walk_options.object_names,
 754                                        obj, xstrdup(arg));
 755                        mark_object_reachable(obj);
 756                        heads++;
 757                        continue;
 758                }
 759                error("invalid parameter: expected sha1, got '%s'", arg);
 760                errors_found |= ERROR_OBJECT;
 761        }
 762
 763        /*
 764         * If we've not been given any explicit head information, do the
 765         * default ones from .git/refs. We also consider the index file
 766         * in this case (ie this implies --cache).
 767         */
 768        if (!argc) {
 769                get_default_heads();
 770                keep_cache_objects = 1;
 771        }
 772
 773        if (keep_cache_objects) {
 774                verify_index_checksum = 1;
 775                read_cache();
 776                for (i = 0; i < active_nr; i++) {
 777                        unsigned int mode;
 778                        struct blob *blob;
 779                        struct object *obj;
 780
 781                        mode = active_cache[i]->ce_mode;
 782                        if (S_ISGITLINK(mode))
 783                                continue;
 784                        blob = lookup_blob(active_cache[i]->oid.hash);
 785                        if (!blob)
 786                                continue;
 787                        obj = &blob->object;
 788                        obj->used = 1;
 789                        if (name_objects)
 790                                add_decoration(fsck_walk_options.object_names,
 791                                        obj,
 792                                        xstrfmt(":%s", active_cache[i]->name));
 793                        mark_object_reachable(obj);
 794                }
 795                if (active_cache_tree)
 796                        fsck_cache_tree(active_cache_tree);
 797        }
 798
 799        check_connectivity();
 800        return errors_found;
 801}