727310afc2327726dd87f5ad6438cd28c07810c9
   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
  14#define REACHABLE 0x0001
  15#define SEEN      0x0002
  16
  17static int show_root;
  18static int show_tags;
  19static int show_unreachable;
  20static int include_reflogs = 1;
  21static int check_full;
  22static int check_strict;
  23static int keep_cache_objects;
  24static unsigned char head_sha1[20];
  25static int errors_found;
  26static int write_lost_and_found;
  27static int verbose;
  28#define ERROR_OBJECT 01
  29#define ERROR_REACHABLE 02
  30
  31#ifdef NO_D_INO_IN_DIRENT
  32#define SORT_DIRENT 0
  33#define DIRENT_SORT_HINT(de) 0
  34#else
  35#define SORT_DIRENT 1
  36#define DIRENT_SORT_HINT(de) ((de)->d_ino)
  37#endif
  38
  39static void objreport(struct object *obj, const char *severity,
  40                      const char *err, va_list params)
  41{
  42        fprintf(stderr, "%s in %s %s: ",
  43                severity, typename(obj->type), sha1_to_hex(obj->sha1));
  44        vfprintf(stderr, err, params);
  45        fputs("\n", stderr);
  46}
  47
  48static int objerror(struct object *obj, const char *err, ...)
  49{
  50        va_list params;
  51        va_start(params, err);
  52        errors_found |= ERROR_OBJECT;
  53        objreport(obj, "error", err, params);
  54        va_end(params);
  55        return -1;
  56}
  57
  58static int objwarning(struct object *obj, const char *err, ...)
  59{
  60        va_list params;
  61        va_start(params, err);
  62        objreport(obj, "warning", err, params);
  63        va_end(params);
  64        return -1;
  65}
  66
  67static int mark_object(struct object *obj, int type, void *data)
  68{
  69        struct tree *tree = NULL;
  70        struct object *parent = data;
  71        int result;
  72
  73        if (!obj) {
  74                printf("broken link from %7s %s\n",
  75                           typename(parent->type), sha1_to_hex(parent->sha1));
  76                printf("broken link from %7s %s\n",
  77                           (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
  78                errors_found |= ERROR_REACHABLE;
  79                return 1;
  80        }
  81
  82        if (type != OBJ_ANY && obj->type != type)
  83                objerror(parent, "wrong object type in link");
  84
  85        if (obj->flags & REACHABLE)
  86                return 0;
  87        obj->flags |= REACHABLE;
  88        if (!obj->parsed) {
  89                if (parent && !has_sha1_file(obj->sha1)) {
  90                        printf("broken link from %7s %s\n",
  91                                 typename(parent->type), sha1_to_hex(parent->sha1));
  92                        printf("              to %7s %s\n",
  93                                 typename(obj->type), sha1_to_hex(obj->sha1));
  94                        errors_found |= ERROR_REACHABLE;
  95                }
  96                return 1;
  97        }
  98
  99        if (obj->type == OBJ_TREE) {
 100                obj->parsed = 0;
 101                tree = (struct tree *)obj;
 102                if (parse_tree(tree) < 0)
 103                        return 1; /* error already displayed */
 104        }
 105        result = fsck_walk(obj, mark_object, obj);
 106        if (tree) {
 107                free(tree->buffer);
 108                tree->buffer = NULL;
 109        }
 110        if (result < 0)
 111                result = 1;
 112
 113        return result;
 114}
 115
 116static void mark_object_reachable(struct object *obj)
 117{
 118        mark_object(obj, OBJ_ANY, 0);
 119}
 120
 121static int mark_used(struct object *obj, int type, void *data)
 122{
 123        if (!obj)
 124                return 1;
 125        obj->used = 1;
 126        return 0;
 127}
 128
 129/*
 130 * Check a single reachable object
 131 */
 132static void check_reachable_object(struct object *obj)
 133{
 134        /*
 135         * We obviously want the object to be parsed,
 136         * except if it was in a pack-file and we didn't
 137         * do a full fsck
 138         */
 139        if (!obj->parsed) {
 140                if (has_sha1_pack(obj->sha1, NULL))
 141                        return; /* it is in pack - forget about it */
 142                printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
 143                errors_found |= ERROR_REACHABLE;
 144                return;
 145        }
 146}
 147
 148/*
 149 * Check a single unreachable object
 150 */
 151static void check_unreachable_object(struct object *obj)
 152{
 153        /*
 154         * Missing unreachable object? Ignore it. It's not like
 155         * we miss it (since it can't be reached), nor do we want
 156         * to complain about it being unreachable (since it does
 157         * not exist).
 158         */
 159        if (!obj->parsed)
 160                return;
 161
 162        /*
 163         * Unreachable object that exists? Show it if asked to,
 164         * since this is something that is prunable.
 165         */
 166        if (show_unreachable) {
 167                printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
 168                return;
 169        }
 170
 171        /*
 172         * "!used" means that nothing at all points to it, including
 173         * other unreachable objects. In other words, it's the "tip"
 174         * of some set of unreachable objects, usually a commit that
 175         * got dropped.
 176         *
 177         * Such starting points are more interesting than some random
 178         * set of unreachable objects, so we show them even if the user
 179         * hasn't asked for _all_ unreachable objects. If you have
 180         * deleted a branch by mistake, this is a prime candidate to
 181         * start looking at, for example.
 182         */
 183        if (!obj->used) {
 184                printf("dangling %s %s\n", typename(obj->type),
 185                       sha1_to_hex(obj->sha1));
 186                if (write_lost_and_found) {
 187                        char *filename = git_path("lost-found/%s/%s",
 188                                obj->type == OBJ_COMMIT ? "commit" : "other",
 189                                sha1_to_hex(obj->sha1));
 190                        FILE *f;
 191
 192                        if (safe_create_leading_directories(filename)) {
 193                                error("Could not create lost-found");
 194                                return;
 195                        }
 196                        if (!(f = fopen(filename, "w")))
 197                                die("Could not open %s", filename);
 198                        if (obj->type == OBJ_BLOB) {
 199                                enum object_type type;
 200                                unsigned long size;
 201                                char *buf = read_sha1_file(obj->sha1,
 202                                                &type, &size);
 203                                if (buf) {
 204                                        fwrite(buf, size, 1, f);
 205                                        free(buf);
 206                                }
 207                        } else
 208                                fprintf(f, "%s\n", sha1_to_hex(obj->sha1));
 209                        fclose(f);
 210                }
 211                return;
 212        }
 213
 214        /*
 215         * Otherwise? It's there, it's unreachable, and some other unreachable
 216         * object points to it. Ignore it - it's not interesting, and we showed
 217         * all the interesting cases above.
 218         */
 219}
 220
 221static void check_object(struct object *obj)
 222{
 223        if (verbose)
 224                fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1));
 225
 226        if (obj->flags & REACHABLE)
 227                check_reachable_object(obj);
 228        else
 229                check_unreachable_object(obj);
 230}
 231
 232static void check_connectivity(void)
 233{
 234        int i, max;
 235
 236        /* Look up all the requirements, warn about missing objects.. */
 237        max = get_max_object_index();
 238        if (verbose)
 239                fprintf(stderr, "Checking connectivity (%d objects)\n", max);
 240
 241        for (i = 0; i < max; i++) {
 242                struct object *obj = get_indexed_object(i);
 243
 244                if (obj)
 245                        check_object(obj);
 246        }
 247}
 248
 249/*
 250 * The entries in a tree are ordered in the _path_ order,
 251 * which means that a directory entry is ordered by adding
 252 * a slash to the end of it.
 253 *
 254 * So a directory called "a" is ordered _after_ a file
 255 * called "a.c", because "a/" sorts after "a.c".
 256 */
 257#define TREE_UNORDERED (-1)
 258#define TREE_HAS_DUPS  (-2)
 259
 260static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 261{
 262        int len1 = strlen(name1);
 263        int len2 = strlen(name2);
 264        int len = len1 < len2 ? len1 : len2;
 265        unsigned char c1, c2;
 266        int cmp;
 267
 268        cmp = memcmp(name1, name2, len);
 269        if (cmp < 0)
 270                return 0;
 271        if (cmp > 0)
 272                return TREE_UNORDERED;
 273
 274        /*
 275         * Ok, the first <len> characters are the same.
 276         * Now we need to order the next one, but turn
 277         * a '\0' into a '/' for a directory entry.
 278         */
 279        c1 = name1[len];
 280        c2 = name2[len];
 281        if (!c1 && !c2)
 282                /*
 283                 * git-write-tree used to write out a nonsense tree that has
 284                 * entries with the same name, one blob and one tree.  Make
 285                 * sure we do not have duplicate entries.
 286                 */
 287                return TREE_HAS_DUPS;
 288        if (!c1 && S_ISDIR(mode1))
 289                c1 = '/';
 290        if (!c2 && S_ISDIR(mode2))
 291                c2 = '/';
 292        return c1 < c2 ? 0 : TREE_UNORDERED;
 293}
 294
 295static int fsck_tree(struct tree *item)
 296{
 297        int retval;
 298        int has_full_path = 0;
 299        int has_empty_name = 0;
 300        int has_zero_pad = 0;
 301        int has_bad_modes = 0;
 302        int has_dup_entries = 0;
 303        int not_properly_sorted = 0;
 304        struct tree_desc desc;
 305        unsigned o_mode;
 306        const char *o_name;
 307        const unsigned char *o_sha1;
 308
 309        if (verbose)
 310                fprintf(stderr, "Checking tree %s\n",
 311                                sha1_to_hex(item->object.sha1));
 312
 313        init_tree_desc(&desc, item->buffer, item->size);
 314
 315        o_mode = 0;
 316        o_name = NULL;
 317        o_sha1 = NULL;
 318        while (desc.size) {
 319                unsigned mode;
 320                const char *name;
 321                const unsigned char *sha1;
 322
 323                sha1 = tree_entry_extract(&desc, &name, &mode);
 324
 325                if (strchr(name, '/'))
 326                        has_full_path = 1;
 327                if (!*name)
 328                        has_empty_name = 1;
 329                has_zero_pad |= *(char *)desc.buffer == '0';
 330                update_tree_entry(&desc);
 331
 332                switch (mode) {
 333                /*
 334                 * Standard modes..
 335                 */
 336                case S_IFREG | 0755:
 337                case S_IFREG | 0644:
 338                case S_IFLNK:
 339                case S_IFDIR:
 340                case S_IFGITLINK:
 341                        break;
 342                /*
 343                 * This is nonstandard, but we had a few of these
 344                 * early on when we honored the full set of mode
 345                 * bits..
 346                 */
 347                case S_IFREG | 0664:
 348                        if (!check_strict)
 349                                break;
 350                default:
 351                        has_bad_modes = 1;
 352                }
 353
 354                if (o_name) {
 355                        switch (verify_ordered(o_mode, o_name, mode, name)) {
 356                        case TREE_UNORDERED:
 357                                not_properly_sorted = 1;
 358                                break;
 359                        case TREE_HAS_DUPS:
 360                                has_dup_entries = 1;
 361                                break;
 362                        default:
 363                                break;
 364                        }
 365                }
 366
 367                o_mode = mode;
 368                o_name = name;
 369                o_sha1 = sha1;
 370        }
 371        free(item->buffer);
 372        item->buffer = NULL;
 373
 374        retval = 0;
 375        if (has_full_path) {
 376                objwarning(&item->object, "contains full pathnames");
 377        }
 378        if (has_empty_name) {
 379                objwarning(&item->object, "contains empty pathname");
 380        }
 381        if (has_zero_pad) {
 382                objwarning(&item->object, "contains zero-padded file modes");
 383        }
 384        if (has_bad_modes) {
 385                objwarning(&item->object, "contains bad file modes");
 386        }
 387        if (has_dup_entries) {
 388                retval = objerror(&item->object, "contains duplicate file entries");
 389        }
 390        if (not_properly_sorted) {
 391                retval = objerror(&item->object, "not properly sorted");
 392        }
 393        return retval;
 394}
 395
 396static int fsck_commit(struct commit *commit)
 397{
 398        char *buffer = commit->buffer;
 399        unsigned char tree_sha1[20], sha1[20];
 400        struct commit_graft *graft;
 401        int parents = 0;
 402
 403        if (verbose)
 404                fprintf(stderr, "Checking commit %s\n",
 405                        sha1_to_hex(commit->object.sha1));
 406
 407        if (memcmp(buffer, "tree ", 5))
 408                return objerror(&commit->object, "invalid format - expected 'tree' line");
 409        if (get_sha1_hex(buffer+5, tree_sha1) || buffer[45] != '\n')
 410                return objerror(&commit->object, "invalid 'tree' line format - bad sha1");
 411        buffer += 46;
 412        while (!memcmp(buffer, "parent ", 7)) {
 413                if (get_sha1_hex(buffer+7, sha1) || buffer[47] != '\n')
 414                        return objerror(&commit->object, "invalid 'parent' line format - bad sha1");
 415                buffer += 48;
 416                parents++;
 417        }
 418        graft = lookup_commit_graft(commit->object.sha1);
 419        if (graft) {
 420                struct commit_list *p = commit->parents;
 421                parents = 0;
 422                while (p) {
 423                        p = p->next;
 424                        parents++;
 425                }
 426                if (graft->nr_parent == -1 && !parents)
 427                        ; /* shallow commit */
 428                else if (graft->nr_parent != parents)
 429                        return objerror(&commit->object, "graft objects missing");
 430        } else {
 431                struct commit_list *p = commit->parents;
 432                while (p && parents) {
 433                        p = p->next;
 434                        parents--;
 435                }
 436                if (p || parents)
 437                        return objerror(&commit->object, "parent objects missing");
 438        }
 439        if (memcmp(buffer, "author ", 7))
 440                return objerror(&commit->object, "invalid format - expected 'author' line");
 441        free(commit->buffer);
 442        commit->buffer = NULL;
 443        if (!commit->tree)
 444                return objerror(&commit->object, "could not load commit's tree %s", tree_sha1);
 445        if (!commit->parents && show_root)
 446                printf("root %s\n", sha1_to_hex(commit->object.sha1));
 447        if (!commit->date)
 448                printf("bad commit date in %s\n",
 449                       sha1_to_hex(commit->object.sha1));
 450        return 0;
 451}
 452
 453static int fsck_tag(struct tag *tag)
 454{
 455        struct object *tagged = tag->tagged;
 456
 457        if (verbose)
 458                fprintf(stderr, "Checking tag %s\n",
 459                        sha1_to_hex(tag->object.sha1));
 460
 461        if (!tagged) {
 462                return objerror(&tag->object, "could not load tagged object");
 463        }
 464        if (!show_tags)
 465                return 0;
 466
 467        printf("tagged %s %s", typename(tagged->type), sha1_to_hex(tagged->sha1));
 468        printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
 469        return 0;
 470}
 471
 472static int fsck_sha1(const unsigned char *sha1)
 473{
 474        struct object *obj = parse_object(sha1);
 475        if (!obj) {
 476                errors_found |= ERROR_OBJECT;
 477                return error("%s: object corrupt or missing",
 478                             sha1_to_hex(sha1));
 479        }
 480        if (obj->flags & SEEN)
 481                return 0;
 482        obj->flags |= SEEN;
 483        if (fsck_walk(obj, mark_used, 0))
 484                objerror(obj, "broken links");
 485        if (obj->type == OBJ_BLOB)
 486                return 0;
 487        if (obj->type == OBJ_TREE)
 488                return fsck_tree((struct tree *) obj);
 489        if (obj->type == OBJ_COMMIT)
 490                return fsck_commit((struct commit *) obj);
 491        if (obj->type == OBJ_TAG)
 492                return fsck_tag((struct tag *) obj);
 493
 494        /* By now, parse_object() would've returned NULL instead. */
 495        return objerror(obj, "unknown type '%d' (internal fsck error)",
 496                        obj->type);
 497}
 498
 499/*
 500 * This is the sorting chunk size: make it reasonably
 501 * big so that we can sort well..
 502 */
 503#define MAX_SHA1_ENTRIES (1024)
 504
 505struct sha1_entry {
 506        unsigned long ino;
 507        unsigned char sha1[20];
 508};
 509
 510static struct {
 511        unsigned long nr;
 512        struct sha1_entry *entry[MAX_SHA1_ENTRIES];
 513} sha1_list;
 514
 515static int ino_compare(const void *_a, const void *_b)
 516{
 517        const struct sha1_entry *a = _a, *b = _b;
 518        unsigned long ino1 = a->ino, ino2 = b->ino;
 519        return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
 520}
 521
 522static void fsck_sha1_list(void)
 523{
 524        int i, nr = sha1_list.nr;
 525
 526        if (SORT_DIRENT)
 527                qsort(sha1_list.entry, nr,
 528                      sizeof(struct sha1_entry *), ino_compare);
 529        for (i = 0; i < nr; i++) {
 530                struct sha1_entry *entry = sha1_list.entry[i];
 531                unsigned char *sha1 = entry->sha1;
 532
 533                sha1_list.entry[i] = NULL;
 534                fsck_sha1(sha1);
 535                free(entry);
 536        }
 537        sha1_list.nr = 0;
 538}
 539
 540static void add_sha1_list(unsigned char *sha1, unsigned long ino)
 541{
 542        struct sha1_entry *entry = xmalloc(sizeof(*entry));
 543        int nr;
 544
 545        entry->ino = ino;
 546        hashcpy(entry->sha1, sha1);
 547        nr = sha1_list.nr;
 548        if (nr == MAX_SHA1_ENTRIES) {
 549                fsck_sha1_list();
 550                nr = 0;
 551        }
 552        sha1_list.entry[nr] = entry;
 553        sha1_list.nr = ++nr;
 554}
 555
 556static void fsck_dir(int i, char *path)
 557{
 558        DIR *dir = opendir(path);
 559        struct dirent *de;
 560
 561        if (!dir)
 562                return;
 563
 564        if (verbose)
 565                fprintf(stderr, "Checking directory %s\n", path);
 566
 567        while ((de = readdir(dir)) != NULL) {
 568                char name[100];
 569                unsigned char sha1[20];
 570                int len = strlen(de->d_name);
 571
 572                switch (len) {
 573                case 2:
 574                        if (de->d_name[1] != '.')
 575                                break;
 576                case 1:
 577                        if (de->d_name[0] != '.')
 578                                break;
 579                        continue;
 580                case 38:
 581                        sprintf(name, "%02x", i);
 582                        memcpy(name+2, de->d_name, len+1);
 583                        if (get_sha1_hex(name, sha1) < 0)
 584                                break;
 585                        add_sha1_list(sha1, DIRENT_SORT_HINT(de));
 586                        continue;
 587                }
 588                fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
 589        }
 590        closedir(dir);
 591}
 592
 593static int default_refs;
 594
 595static int fsck_handle_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
 596                const char *email, unsigned long timestamp, int tz,
 597                const char *message, void *cb_data)
 598{
 599        struct object *obj;
 600
 601        if (verbose)
 602                fprintf(stderr, "Checking reflog %s->%s\n",
 603                        sha1_to_hex(osha1), sha1_to_hex(nsha1));
 604
 605        if (!is_null_sha1(osha1)) {
 606                obj = lookup_object(osha1);
 607                if (obj) {
 608                        obj->used = 1;
 609                        mark_object_reachable(obj);
 610                }
 611        }
 612        obj = lookup_object(nsha1);
 613        if (obj) {
 614                obj->used = 1;
 615                mark_object_reachable(obj);
 616        }
 617        return 0;
 618}
 619
 620static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, int flag, void *cb_data)
 621{
 622        for_each_reflog_ent(logname, fsck_handle_reflog_ent, NULL);
 623        return 0;
 624}
 625
 626static int is_branch(const char *refname)
 627{
 628        return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
 629}
 630
 631static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
 632{
 633        struct object *obj;
 634
 635        obj = parse_object(sha1);
 636        if (!obj) {
 637                error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
 638                /* We'll continue with the rest despite the error.. */
 639                return 0;
 640        }
 641        if (obj->type != OBJ_COMMIT && is_branch(refname))
 642                error("%s: not a commit", refname);
 643        default_refs++;
 644        obj->used = 1;
 645        mark_object_reachable(obj);
 646
 647        return 0;
 648}
 649
 650static void get_default_heads(void)
 651{
 652        for_each_ref(fsck_handle_ref, NULL);
 653        if (include_reflogs)
 654                for_each_reflog(fsck_handle_reflog, NULL);
 655
 656        /*
 657         * Not having any default heads isn't really fatal, but
 658         * it does mean that "--unreachable" no longer makes any
 659         * sense (since in this case everything will obviously
 660         * be unreachable by definition.
 661         *
 662         * Showing dangling objects is valid, though (as those
 663         * dangling objects are likely lost heads).
 664         *
 665         * So we just print a warning about it, and clear the
 666         * "show_unreachable" flag.
 667         */
 668        if (!default_refs) {
 669                fprintf(stderr, "notice: No default references\n");
 670                show_unreachable = 0;
 671        }
 672}
 673
 674static void fsck_object_dir(const char *path)
 675{
 676        int i;
 677
 678        if (verbose)
 679                fprintf(stderr, "Checking object directory\n");
 680
 681        for (i = 0; i < 256; i++) {
 682                static char dir[4096];
 683                sprintf(dir, "%s/%02x", path, i);
 684                fsck_dir(i, dir);
 685        }
 686        fsck_sha1_list();
 687}
 688
 689static int fsck_head_link(void)
 690{
 691        unsigned char sha1[20];
 692        int flag;
 693        int null_is_error = 0;
 694        const char *head_points_at = resolve_ref("HEAD", sha1, 0, &flag);
 695
 696        if (verbose)
 697                fprintf(stderr, "Checking HEAD link\n");
 698
 699        if (!head_points_at)
 700                return error("Invalid HEAD");
 701        if (!strcmp(head_points_at, "HEAD"))
 702                /* detached HEAD */
 703                null_is_error = 1;
 704        else if (prefixcmp(head_points_at, "refs/heads/"))
 705                return error("HEAD points to something strange (%s)",
 706                             head_points_at);
 707        if (is_null_sha1(sha1)) {
 708                if (null_is_error)
 709                        return error("HEAD: detached HEAD points at nothing");
 710                fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
 711                        head_points_at + 11);
 712        }
 713        return 0;
 714}
 715
 716static int fsck_cache_tree(struct cache_tree *it)
 717{
 718        int i;
 719        int err = 0;
 720
 721        if (verbose)
 722                fprintf(stderr, "Checking cache tree\n");
 723
 724        if (0 <= it->entry_count) {
 725                struct object *obj = parse_object(it->sha1);
 726                if (!obj) {
 727                        error("%s: invalid sha1 pointer in cache-tree",
 728                              sha1_to_hex(it->sha1));
 729                        return 1;
 730                }
 731                mark_object_reachable(obj);
 732                obj->used = 1;
 733                if (obj->type != OBJ_TREE)
 734                        err |= objerror(obj, "non-tree in cache-tree");
 735        }
 736        for (i = 0; i < it->subtree_nr; i++)
 737                err |= fsck_cache_tree(it->down[i]->cache_tree);
 738        return err;
 739}
 740
 741static char const * const fsck_usage[] = {
 742        "git-fsck [options] [<object>...]",
 743        NULL
 744};
 745
 746static struct option fsck_opts[] = {
 747        OPT__VERBOSE(&verbose),
 748        OPT_BOOLEAN(0, "unreachable", &show_unreachable, "show unreachable objects"),
 749        OPT_BOOLEAN(0, "tags", &show_tags, "report tags"),
 750        OPT_BOOLEAN(0, "root", &show_root, "report root nodes"),
 751        OPT_BOOLEAN(0, "cache", &keep_cache_objects, "make index objects head nodes"),
 752        OPT_BOOLEAN(0, "reflogs", &include_reflogs, "make reflogs head nodes (default)"),
 753        OPT_BOOLEAN(0, "full", &check_full, "also consider alternate objects"),
 754        OPT_BOOLEAN(0, "strict", &check_strict, "enable more strict checking"),
 755        OPT_BOOLEAN(0, "lost-found", &write_lost_and_found,
 756                                "write dangling objects in .git/lost-found"),
 757        OPT_END(),
 758};
 759
 760int cmd_fsck(int argc, const char **argv, const char *prefix)
 761{
 762        int i, heads;
 763
 764        errors_found = 0;
 765
 766        argc = parse_options(argc, argv, fsck_opts, fsck_usage, 0);
 767        if (write_lost_and_found) {
 768                check_full = 1;
 769                include_reflogs = 0;
 770        }
 771
 772        fsck_head_link();
 773        fsck_object_dir(get_object_directory());
 774        if (check_full) {
 775                struct alternate_object_database *alt;
 776                struct packed_git *p;
 777                prepare_alt_odb();
 778                for (alt = alt_odb_list; alt; alt = alt->next) {
 779                        char namebuf[PATH_MAX];
 780                        int namelen = alt->name - alt->base;
 781                        memcpy(namebuf, alt->base, namelen);
 782                        namebuf[namelen - 1] = 0;
 783                        fsck_object_dir(namebuf);
 784                }
 785                prepare_packed_git();
 786                for (p = packed_git; p; p = p->next)
 787                        /* verify gives error messages itself */
 788                        verify_pack(p, 0);
 789
 790                for (p = packed_git; p; p = p->next) {
 791                        uint32_t j, num;
 792                        if (open_pack_index(p))
 793                                continue;
 794                        num = p->num_objects;
 795                        for (j = 0; j < num; j++)
 796                                fsck_sha1(nth_packed_object_sha1(p, j));
 797                }
 798        }
 799
 800        heads = 0;
 801        for (i = 1; i < argc; i++) {
 802                const char *arg = argv[i];
 803                if (!get_sha1(arg, head_sha1)) {
 804                        struct object *obj = lookup_object(head_sha1);
 805
 806                        /* Error is printed by lookup_object(). */
 807                        if (!obj)
 808                                continue;
 809
 810                        obj->used = 1;
 811                        mark_object_reachable(obj);
 812                        heads++;
 813                        continue;
 814                }
 815                error("invalid parameter: expected sha1, got '%s'", arg);
 816        }
 817
 818        /*
 819         * If we've not been given any explicit head information, do the
 820         * default ones from .git/refs. We also consider the index file
 821         * in this case (ie this implies --cache).
 822         */
 823        if (!heads) {
 824                get_default_heads();
 825                keep_cache_objects = 1;
 826        }
 827
 828        if (keep_cache_objects) {
 829                read_cache();
 830                for (i = 0; i < active_nr; i++) {
 831                        unsigned int mode;
 832                        struct blob *blob;
 833                        struct object *obj;
 834
 835                        mode = ntohl(active_cache[i]->ce_mode);
 836                        if (S_ISGITLINK(mode))
 837                                continue;
 838                        blob = lookup_blob(active_cache[i]->sha1);
 839                        if (!blob)
 840                                continue;
 841                        obj = &blob->object;
 842                        obj->used = 1;
 843                        mark_object_reachable(obj);
 844                }
 845                if (active_cache_tree)
 846                        fsck_cache_tree(active_cache_tree);
 847        }
 848
 849        check_connectivity();
 850        return errors_found;
 851}