fsck-objects.c

   1 #include <sys/types.h>
   2 #include <dirent.h>
   3
   4 #include "cache.h"
   5 #include "commit.h"
   6 #include "tree.h"
   7 #include "blob.h"
   8 #include "tag.h"
   9 #include "refs.h"
  10 #include "pack.h"
  11 #include "cache-tree.h"
  12 #include "tree-walk.h"
  13
  14 #define REACHABLE 0x0001
  15 #define SEEN      0x0002
  16
  17 static int show_root = 0;
  18 static int show_tags = 0;
  19 static int show_unreachable = 0;
  20 static int check_full = 0;
  21 static int check_strict = 0;
  22 static int keep_cache_objects = 0;
  23 static unsigned char head_sha1[20];
  24
  25 #ifdef NO_D_INO_IN_DIRENT
  26 #define SORT_DIRENT 0
  27 #define DIRENT_SORT_HINT(de) 0
  28 #else
  29 #define SORT_DIRENT 1
  30 #define DIRENT_SORT_HINT(de) ((de)->d_ino)
  31 #endif
  32
  33 static void objreport(struct object *obj, const char *severity,
  34                       const char *err, va_list params)
  35 {
  36         fprintf(stderr, "%s in %s %s: ",
  37                 severity, typename(obj->type), sha1_to_hex(obj->sha1));
  38         vfprintf(stderr, err, params);
  39         fputs("\n", stderr);
  40 }
  41
  42 static int objerror(struct object *obj, const char *err, ...)
  43 {
  44         va_list params;
  45         va_start(params, err);
  46         objreport(obj, "error", err, params);
  47         va_end(params);
  48         return -1;
  49 }
  50
  51 static int objwarning(struct object *obj, const char *err, ...)
  52 {
  53         va_list params;
  54         va_start(params, err);
  55         objreport(obj, "warning", err, params);
  56         va_end(params);
  57         return -1;
  58 }
  59
  60
  61 static void check_connectivity(void)
  62 {
  63         int i;
  64
  65         /* Look up all the requirements, warn about missing objects.. */
  66         for (i = 0; i < obj_allocs; i++) {
  67                 struct object *obj = objs[i];
  68
  69                 if (!obj)
  70                         continue;
  71
  72                 if (!obj->parsed) {
  73                         if (has_sha1_file(obj->sha1))
  74                                 ; /* it is in pack */
  75                         else
  76                                 printf("missing %s %s\n",
  77                                        typename(obj->type), sha1_to_hex(obj->sha1));
  78                         continue;
  79                 }
  80
  81                 if (obj->refs) {
  82                         const struct object_refs *refs = obj->refs;
  83                         unsigned j;
  84                         for (j = 0; j < refs->count; j++) {
  85                                 struct object *ref = refs->ref[j];
  86                                 if (ref->parsed ||
  87                                     (has_sha1_file(ref->sha1)))
  88                                         continue;
  89                                 printf("broken link from %7s %s\n",
  90                                        typename(obj->type), sha1_to_hex(obj->sha1));
  91                                 printf("              to %7s %s\n",
  92                                        typename(ref->type), sha1_to_hex(ref->sha1));
  93                         }
  94                 }
  95
  96                 if (show_unreachable && !(obj->flags & REACHABLE)) {
  97                         printf("unreachable %s %s\n",
  98                                typename(obj->type), sha1_to_hex(obj->sha1));
  99                         continue;
 100                 }
 101
 102                 if (!obj->used) {
 103                         printf("dangling %s %s\n", typename(obj->type),
 104                                sha1_to_hex(obj->sha1));
 105                 }
 106         }
 107 }
 108
 109 /*
 110  * The entries in a tree are ordered in the _path_ order,
 111  * which means that a directory entry is ordered by adding
 112  * a slash to the end of it.
 113  *
 114  * So a directory called "a" is ordered _after_ a file
 115  * called "a.c", because "a/" sorts after "a.c".
 116  */
 117 #define TREE_UNORDERED (-1)
 118 #define TREE_HAS_DUPS  (-2)
 119
 120 static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 121 {
 122         int len1 = strlen(name1);
 123         int len2 = strlen(name2);
 124         int len = len1 < len2 ? len1 : len2;
 125         unsigned char c1, c2;
 126         int cmp;
 127
 128         cmp = memcmp(name1, name2, len);
 129         if (cmp < 0)
 130                 return 0;
 131         if (cmp > 0)
 132                 return TREE_UNORDERED;
 133
 134         /*
 135          * Ok, the first <len> characters are the same.
 136          * Now we need to order the next one, but turn
 137          * a '\0' into a '/' for a directory entry.
 138          */
 139         c1 = name1[len];
 140         c2 = name2[len];
 141         if (!c1 && !c2)
 142                 /*
 143                  * git-write-tree used to write out a nonsense tree that has
 144                  * entries with the same name, one blob and one tree.  Make
 145                  * sure we do not have duplicate entries.
 146                  */
 147                 return TREE_HAS_DUPS;
 148         if (!c1 && S_ISDIR(mode1))
 149                 c1 = '/';
 150         if (!c2 && S_ISDIR(mode2))
 151                 c2 = '/';
 152         return c1 < c2 ? 0 : TREE_UNORDERED;
 153 }
 154
 155 static int fsck_tree(struct tree *item)
 156 {
 157         int retval;
 158         int has_full_path = 0;
 159         int has_zero_pad = 0;
 160         int has_bad_modes = 0;
 161         int has_dup_entries = 0;
 162         int not_properly_sorted = 0;
 163         struct tree_desc desc;
 164         unsigned o_mode;
 165         const char *o_name;
 166         const unsigned char *o_sha1;
 167
 168         desc.buf = item->buffer;
 169         desc.size = item->size;
 170
 171         o_mode = 0;
 172         o_name = NULL;
 173         o_sha1 = NULL;
 174         while (desc.size) {
 175                 unsigned mode;
 176                 const char *name;
 177                 const unsigned char *sha1;
 178
 179                 sha1 = tree_entry_extract(&desc, &name, &mode);
 180
 181                 if (strchr(name, '/'))
 182                         has_full_path = 1;
 183                 has_zero_pad |= *(char *)desc.buf == '0';
 184                 update_tree_entry(&desc);
 185
 186                 switch (mode) {
 187                 /*
 188                  * Standard modes..
 189                  */
 190                 case S_IFREG | 0755:
 191                 case S_IFREG | 0644:
 192                 case S_IFLNK:
 193                 case S_IFDIR:
 194                         break;
 195                 /*
 196                  * This is nonstandard, but we had a few of these
 197                  * early on when we honored the full set of mode
 198                  * bits..
 199                  */
 200                 case S_IFREG | 0664:
 201                         if (!check_strict)
 202                                 break;
 203                 default:
 204                         has_bad_modes = 1;
 205                 }
 206
 207                 if (o_name) {
 208                         switch (verify_ordered(o_mode, o_name, mode, name)) {
 209                         case TREE_UNORDERED:
 210                                 not_properly_sorted = 1;
 211                                 break;
 212                         case TREE_HAS_DUPS:
 213                                 has_dup_entries = 1;
 214                                 break;
 215                         default:
 216                                 break;
 217                         }
 218                 }
 219
 220                 o_mode = mode;
 221                 o_name = name;
 222                 o_sha1 = sha1;
 223         }
 224         free(item->buffer);
 225         item->buffer = NULL;
 226
 227         retval = 0;
 228         if (has_full_path) {
 229                 objwarning(&item->object, "contains full pathnames");
 230         }
 231         if (has_zero_pad) {
 232                 objwarning(&item->object, "contains zero-padded file modes");
 233         }
 234         if (has_bad_modes) {
 235                 objwarning(&item->object, "contains bad file modes");
 236         }
 237         if (has_dup_entries) {
 238                 retval = objerror(&item->object, "contains duplicate file entries");
 239         }
 240         if (not_properly_sorted) {
 241                 retval = objerror(&item->object, "not properly sorted");
 242         }
 243         return retval;
 244 }
 245
 246 static int fsck_commit(struct commit *commit)
 247 {
 248         char *buffer = commit->buffer;
 249         unsigned char tree_sha1[20], sha1[20];
 250
 251         if (memcmp(buffer, "tree ", 5))
 252                 return objerror(&commit->object, "invalid format - expected 'tree' line");
 253         if (get_sha1_hex(buffer+5, tree_sha1) || buffer[45] != '\n')
 254                 return objerror(&commit->object, "invalid 'tree' line format - bad sha1");
 255         buffer += 46;
 256         while (!memcmp(buffer, "parent ", 7)) {
 257                 if (get_sha1_hex(buffer+7, sha1) || buffer[47] != '\n')
 258                         return objerror(&commit->object, "invalid 'parent' line format - bad sha1");
 259                 buffer += 48;
 260         }
 261         if (memcmp(buffer, "author ", 7))
 262                 return objerror(&commit->object, "invalid format - expected 'author' line");
 263         free(commit->buffer);
 264         commit->buffer = NULL;
 265         if (!commit->tree)
 266                 return objerror(&commit->object, "could not load commit's tree %s", tree_sha1);
 267         if (!commit->parents && show_root)
 268                 printf("root %s\n", sha1_to_hex(commit->object.sha1));
 269         if (!commit->date)
 270                 printf("bad commit date in %s\n",
 271                        sha1_to_hex(commit->object.sha1));
 272         return 0;
 273 }
 274
 275 static int fsck_tag(struct tag *tag)
 276 {
 277         struct object *tagged = tag->tagged;
 278
 279         if (!tagged) {
 280                 return objerror(&tag->object, "could not load tagged object");
 281         }
 282         if (!show_tags)
 283                 return 0;
 284
 285         printf("tagged %s %s", typename(tagged->type), sha1_to_hex(tagged->sha1));
 286         printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
 287         return 0;
 288 }
 289
 290 static int fsck_sha1(unsigned char *sha1)
 291 {
 292         struct object *obj = parse_object(sha1);
 293         if (!obj)
 294                 return error("%s: object not found", sha1_to_hex(sha1));
 295         if (obj->flags & SEEN)
 296                 return 0;
 297         obj->flags |= SEEN;
 298         if (obj->type == TYPE_BLOB)
 299                 return 0;
 300         if (obj->type == TYPE_TREE)
 301                 return fsck_tree((struct tree *) obj);
 302         if (obj->type == TYPE_COMMIT)
 303                 return fsck_commit((struct commit *) obj);
 304         if (obj->type == TYPE_TAG)
 305                 return fsck_tag((struct tag *) obj);
 306         /* By now, parse_object() would've returned NULL instead. */
 307         return objerror(obj, "unknown type '%d' (internal fsck error)", obj->type);
 308 }
 309
 310 /*
 311  * This is the sorting chunk size: make it reasonably
 312  * big so that we can sort well..
 313  */
 314 #define MAX_SHA1_ENTRIES (1024)
 315
 316 struct sha1_entry {
 317         unsigned long ino;
 318         unsigned char sha1[20];
 319 };
 320
 321 static struct {
 322         unsigned long nr;
 323         struct sha1_entry *entry[MAX_SHA1_ENTRIES];
 324 } sha1_list;
 325
 326 static int ino_compare(const void *_a, const void *_b)
 327 {
 328         const struct sha1_entry *a = _a, *b = _b;
 329         unsigned long ino1 = a->ino, ino2 = b->ino;
 330         return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
 331 }
 332
 333 static void fsck_sha1_list(void)
 334 {
 335         int i, nr = sha1_list.nr;
 336
 337         if (SORT_DIRENT)
 338                 qsort(sha1_list.entry, nr,
 339                       sizeof(struct sha1_entry *), ino_compare);
 340         for (i = 0; i < nr; i++) {
 341                 struct sha1_entry *entry = sha1_list.entry[i];
 342                 unsigned char *sha1 = entry->sha1;
 343
 344                 sha1_list.entry[i] = NULL;
 345                 fsck_sha1(sha1);
 346                 free(entry);
 347         }
 348         sha1_list.nr = 0;
 349 }
 350
 351 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
 352 {
 353         struct sha1_entry *entry = xmalloc(sizeof(*entry));
 354         int nr;
 355
 356         entry->ino = ino;
 357         memcpy(entry->sha1, sha1, 20);
 358         nr = sha1_list.nr;
 359         if (nr == MAX_SHA1_ENTRIES) {
 360                 fsck_sha1_list();
 361                 nr = 0;
 362         }
 363         sha1_list.entry[nr] = entry;
 364         sha1_list.nr = ++nr;
 365 }
 366
 367 static int fsck_dir(int i, char *path)
 368 {
 369         DIR *dir = opendir(path);
 370         struct dirent *de;
 371
 372         if (!dir)
 373                 return 0;
 374
 375         while ((de = readdir(dir)) != NULL) {
 376                 char name[100];
 377                 unsigned char sha1[20];
 378                 int len = strlen(de->d_name);
 379
 380                 switch (len) {
 381                 case 2:
 382                         if (de->d_name[1] != '.')
 383                                 break;
 384                 case 1:
 385                         if (de->d_name[0] != '.')
 386                                 break;
 387                         continue;
 388                 case 38:
 389                         sprintf(name, "%02x", i);
 390                         memcpy(name+2, de->d_name, len+1);
 391                         if (get_sha1_hex(name, sha1) < 0)
 392                                 break;
 393                         add_sha1_list(sha1, DIRENT_SORT_HINT(de));
 394                         continue;
 395                 }
 396                 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
 397         }
 398         closedir(dir);
 399         return 0;
 400 }
 401
 402 static int default_refs = 0;
 403
 404 static int fsck_handle_ref(const char *refname, const unsigned char *sha1)
 405 {
 406         struct object *obj;
 407
 408         obj = lookup_object(sha1);
 409         if (!obj) {
 410                 if (has_sha1_file(sha1)) {
 411                         default_refs++;
 412                         return 0; /* it is in a pack */
 413                 }
 414                 error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
 415                 /* We'll continue with the rest despite the error.. */
 416                 return 0;
 417         }
 418         default_refs++;
 419         obj->used = 1;
 420         mark_reachable(obj, REACHABLE);
 421         return 0;
 422 }
 423
 424 static void get_default_heads(void)
 425 {
 426         for_each_ref(fsck_handle_ref);
 427         if (!default_refs)
 428                 die("No default references");
 429 }
 430
 431 static void fsck_object_dir(const char *path)
 432 {
 433         int i;
 434         for (i = 0; i < 256; i++) {
 435                 static char dir[4096];
 436                 sprintf(dir, "%s/%02x", path, i);
 437                 fsck_dir(i, dir);
 438         }
 439         fsck_sha1_list();
 440 }
 441
 442 static int fsck_head_link(void)
 443 {
 444         unsigned char sha1[20];
 445         const char *git_HEAD = strdup(git_path("HEAD"));
 446         const char *git_refs_heads_master = resolve_ref(git_HEAD, sha1, 1);
 447         int pfxlen = strlen(git_HEAD) - 4; /* strip .../.git/ part */
 448
 449         if (!git_refs_heads_master)
 450                 return error("HEAD is not a symbolic ref");
 451         if (strncmp(git_refs_heads_master + pfxlen, "refs/heads/", 11))
 452                 return error("HEAD points to something strange (%s)",
 453                              git_refs_heads_master + pfxlen);
 454         if (!memcmp(null_sha1, sha1, 20))
 455                 return error("HEAD: not a valid git pointer");
 456         return 0;
 457 }
 458
 459 static int fsck_cache_tree(struct cache_tree *it)
 460 {
 461         int i;
 462         int err = 0;
 463
 464         if (0 <= it->entry_count) {
 465                 struct object *obj = parse_object(it->sha1);
 466                 if (!obj) {
 467                         error("%s: invalid sha1 pointer in cache-tree",
 468                               sha1_to_hex(it->sha1));
 469                         return 1;
 470                 }
 471                 mark_reachable(obj, REACHABLE);
 472                 obj->used = 1;
 473                 if (obj->type != TYPE_TREE)
 474                         err |= objerror(obj, "non-tree in cache-tree");
 475         }
 476         for (i = 0; i < it->subtree_nr; i++)
 477                 err |= fsck_cache_tree(it->down[i]->cache_tree);
 478         return err;
 479 }
 480
 481 int main(int argc, char **argv)
 482 {
 483         int i, heads;
 484
 485         track_object_refs = 1;
 486         setup_git_directory();
 487
 488         for (i = 1; i < argc; i++) {
 489                 const char *arg = argv[i];
 490
 491                 if (!strcmp(arg, "--unreachable")) {
 492                         show_unreachable = 1;
 493                         continue;
 494                 }
 495                 if (!strcmp(arg, "--tags")) {
 496                         show_tags = 1;
 497                         continue;
 498                 }
 499                 if (!strcmp(arg, "--root")) {
 500                         show_root = 1;
 501                         continue;
 502                 }
 503                 if (!strcmp(arg, "--cache")) {
 504                         keep_cache_objects = 1;
 505                         continue;
 506                 }
 507                 if (!strcmp(arg, "--full")) {
 508                         check_full = 1;
 509                         continue;
 510                 }
 511                 if (!strcmp(arg, "--strict")) {
 512                         check_strict = 1;
 513                         continue;
 514                 }
 515                 if (*arg == '-')
 516                         usage("git-fsck-objects [--tags] [--root] [[--unreachable] [--cache] [--full] [--strict] <head-sha1>*]");
 517         }
 518
 519         fsck_head_link();
 520         fsck_object_dir(get_object_directory());
 521         if (check_full) {
 522                 struct alternate_object_database *alt;
 523                 struct packed_git *p;
 524                 prepare_alt_odb();
 525                 for (alt = alt_odb_list; alt; alt = alt->next) {
 526                         char namebuf[PATH_MAX];
 527                         int namelen = alt->name - alt->base;
 528                         memcpy(namebuf, alt->base, namelen);
 529                         namebuf[namelen - 1] = 0;
 530                         fsck_object_dir(namebuf);
 531                 }
 532                 prepare_packed_git();
 533                 for (p = packed_git; p; p = p->next)
 534                         /* verify gives error messages itself */
 535                         verify_pack(p, 0);
 536
 537                 for (p = packed_git; p; p = p->next) {
 538                         int num = num_packed_objects(p);
 539                         for (i = 0; i < num; i++) {
 540                                 unsigned char sha1[20];
 541                                 nth_packed_object_sha1(p, i, sha1);
 542                                 fsck_sha1(sha1);
 543                         }
 544                 }
 545         }
 546
 547         heads = 0;
 548         for (i = 1; i < argc; i++) {
 549                 const char *arg = argv[i];
 550
 551                 if (*arg == '-')
 552                         continue;
 553
 554                 if (!get_sha1(arg, head_sha1)) {
 555                         struct object *obj = lookup_object(head_sha1);
 556
 557                         /* Error is printed by lookup_object(). */
 558                         if (!obj)
 559                                 continue;
 560
 561                         obj->used = 1;
 562                         mark_reachable(obj, REACHABLE);
 563                         heads++;
 564                         continue;
 565                 }
 566                 error("invalid parameter: expected sha1, got '%s'", arg);
 567         }
 568
 569         /*
 570          * If we've not been given any explicit head information, do the
 571          * default ones from .git/refs. We also consider the index file
 572          * in this case (ie this implies --cache).
 573          */
 574         if (!heads) {
 575                 get_default_heads();
 576                 keep_cache_objects = 1;
 577         }
 578
 579         if (keep_cache_objects) {
 580                 int i;
 581                 read_cache();
 582                 for (i = 0; i < active_nr; i++) {
 583                         struct blob *blob = lookup_blob(active_cache[i]->sha1);
 584                         struct object *obj;
 585                         if (!blob)
 586                                 continue;
 587                         obj = &blob->object;
 588                         obj->used = 1;
 589                         mark_reachable(obj, REACHABLE);
 590                 }
 591                 if (active_cache_tree)
 592                         fsck_cache_tree(active_cache_tree);
 593         }
 594
 595         check_connectivity();
 596         return 0;
 597 }