fsck.c

   1 #include "cache.h"
   2 #include "object.h"
   3 #include "blob.h"
   4 #include "tree.h"
   5 #include "tree-walk.h"
   6 #include "commit.h"
   7 #include "tag.h"
   8 #include "fsck.h"
   9 #include "refs.h"
  10 #include "utf8.h"
  11
  12 #define FOREACH_MSG_ID(FUNC) \
  13         /* errors */ \
  14         FUNC(BAD_DATE, ERROR) \
  15         FUNC(BAD_DATE_OVERFLOW, ERROR) \
  16         FUNC(BAD_EMAIL, ERROR) \
  17         FUNC(BAD_NAME, ERROR) \
  18         FUNC(BAD_OBJECT_SHA1, ERROR) \
  19         FUNC(BAD_PARENT_SHA1, ERROR) \
  20         FUNC(BAD_TAG_OBJECT, ERROR) \
  21         FUNC(BAD_TIMEZONE, ERROR) \
  22         FUNC(BAD_TREE, ERROR) \
  23         FUNC(BAD_TREE_SHA1, ERROR) \
  24         FUNC(BAD_TYPE, ERROR) \
  25         FUNC(DUPLICATE_ENTRIES, ERROR) \
  26         FUNC(MISSING_AUTHOR, ERROR) \
  27         FUNC(MISSING_COMMITTER, ERROR) \
  28         FUNC(MISSING_EMAIL, ERROR) \
  29         FUNC(MISSING_GRAFT, ERROR) \
  30         FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  31         FUNC(MISSING_OBJECT, ERROR) \
  32         FUNC(MISSING_PARENT, ERROR) \
  33         FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  34         FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  35         FUNC(MISSING_TAG, ERROR) \
  36         FUNC(MISSING_TAG_ENTRY, ERROR) \
  37         FUNC(MISSING_TAG_OBJECT, ERROR) \
  38         FUNC(MISSING_TREE, ERROR) \
  39         FUNC(MISSING_TYPE, ERROR) \
  40         FUNC(MISSING_TYPE_ENTRY, ERROR) \
  41         FUNC(MULTIPLE_AUTHORS, ERROR) \
  42         FUNC(NUL_IN_HEADER, ERROR) \
  43         FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
  44         FUNC(TREE_NOT_SORTED, ERROR) \
  45         FUNC(UNKNOWN_TYPE, ERROR) \
  46         FUNC(UNTERMINATED_HEADER, ERROR) \
  47         FUNC(ZERO_PADDED_DATE, ERROR) \
  48         /* warnings */ \
  49         FUNC(BAD_FILEMODE, WARN) \
  50         FUNC(BAD_TAG_NAME, WARN) \
  51         FUNC(EMPTY_NAME, WARN) \
  52         FUNC(FULL_PATHNAME, WARN) \
  53         FUNC(HAS_DOT, WARN) \
  54         FUNC(HAS_DOTDOT, WARN) \
  55         FUNC(HAS_DOTGIT, WARN) \
  56         FUNC(MISSING_TAGGER_ENTRY, WARN) \
  57         FUNC(NULL_SHA1, WARN) \
  58         FUNC(ZERO_PADDED_FILEMODE, WARN)
  59
  60 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
  61 enum fsck_msg_id {
  62         FOREACH_MSG_ID(MSG_ID)
  63         FSCK_MSG_MAX
  64 };
  65 #undef MSG_ID
  66
  67 #define STR(x) #x
  68 #define MSG_ID(id, msg_type) { STR(id), NULL, FSCK_##msg_type },
  69 static struct {
  70         const char *id_string;
  71         const char *downcased;
  72         int msg_type;
  73 } msg_id_info[FSCK_MSG_MAX + 1] = {
  74         FOREACH_MSG_ID(MSG_ID)
  75         { NULL, NULL, -1 }
  76 };
  77 #undef MSG_ID
  78
  79 static int parse_msg_id(const char *text)
  80 {
  81         int i;
  82
  83         if (!msg_id_info[0].downcased) {
  84                 /* convert id_string to lower case, without underscores. */
  85                 for (i = 0; i < FSCK_MSG_MAX; i++) {
  86                         const char *p = msg_id_info[i].id_string;
  87                         int len = strlen(p);
  88                         char *q = xmalloc(len);
  89
  90                         msg_id_info[i].downcased = q;
  91                         while (*p)
  92                                 if (*p == '_')
  93                                         p++;
  94                                 else
  95                                         *(q)++ = tolower(*(p)++);
  96                         *q = '\0';
  97                 }
  98         }
  99
 100         for (i = 0; i < FSCK_MSG_MAX; i++)
 101                 if (!strcmp(text, msg_id_info[i].downcased))
 102                         return i;
 103
 104         return -1;
 105 }
 106
 107 static int fsck_msg_type(enum fsck_msg_id msg_id,
 108         struct fsck_options *options)
 109 {
 110         int msg_type;
 111
 112         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 113
 114         if (options->msg_type)
 115                 msg_type = options->msg_type[msg_id];
 116         else {
 117                 msg_type = msg_id_info[msg_id].msg_type;
 118                 if (options->strict && msg_type == FSCK_WARN)
 119                         msg_type = FSCK_ERROR;
 120         }
 121
 122         return msg_type;
 123 }
 124
 125 static int parse_msg_type(const char *str)
 126 {
 127         if (!strcmp(str, "error"))
 128                 return FSCK_ERROR;
 129         else if (!strcmp(str, "warn"))
 130                 return FSCK_WARN;
 131         else
 132                 die("Unknown fsck message type: '%s'", str);
 133 }
 134
 135 int is_valid_msg_type(const char *msg_id, const char *msg_type)
 136 {
 137         if (parse_msg_id(msg_id) < 0)
 138                 return 0;
 139         parse_msg_type(msg_type);
 140         return 1;
 141 }
 142
 143 void fsck_set_msg_type(struct fsck_options *options,
 144                 const char *msg_id, const char *msg_type)
 145 {
 146         int id = parse_msg_id(msg_id), type;
 147
 148         if (id < 0)
 149                 die("Unhandled message id: %s", msg_id);
 150         type = parse_msg_type(msg_type);
 151
 152         if (!options->msg_type) {
 153                 int i;
 154                 int *msg_type = xmalloc(sizeof(int) * FSCK_MSG_MAX);
 155                 for (i = 0; i < FSCK_MSG_MAX; i++)
 156                         msg_type[i] = fsck_msg_type(i, options);
 157                 options->msg_type = msg_type;
 158         }
 159
 160         options->msg_type[id] = type;
 161 }
 162
 163 void fsck_set_msg_types(struct fsck_options *options, const char *values)
 164 {
 165         char *buf = xstrdup(values), *to_free = buf;
 166         int done = 0;
 167
 168         while (!done) {
 169                 int len = strcspn(buf, " ,|"), equal;
 170
 171                 done = !buf[len];
 172                 if (!len) {
 173                         buf++;
 174                         continue;
 175                 }
 176                 buf[len] = '\0';
 177
 178                 for (equal = 0;
 179                      equal < len && buf[equal] != '=' && buf[equal] != ':';
 180                      equal++)
 181                         buf[equal] = tolower(buf[equal]);
 182                 buf[equal] = '\0';
 183
 184                 if (equal == len)
 185                         die("Missing '=': '%s'", buf);
 186
 187                 fsck_set_msg_type(options, buf, buf + equal + 1);
 188                 buf += len + 1;
 189         }
 190         free(to_free);
 191 }
 192
 193 static void append_msg_id(struct strbuf *sb, const char *msg_id)
 194 {
 195         for (;;) {
 196                 char c = *(msg_id)++;
 197
 198                 if (!c)
 199                         break;
 200                 if (c != '_')
 201                         strbuf_addch(sb, tolower(c));
 202                 else {
 203                         assert(*msg_id);
 204                         strbuf_addch(sb, *(msg_id)++);
 205                 }
 206         }
 207
 208         strbuf_addstr(sb, ": ");
 209 }
 210
 211 __attribute__((format (printf, 4, 5)))
 212 static int report(struct fsck_options *options, struct object *object,
 213         enum fsck_msg_id id, const char *fmt, ...)
 214 {
 215         va_list ap;
 216         struct strbuf sb = STRBUF_INIT;
 217         int msg_type = fsck_msg_type(id, options), result;
 218
 219         append_msg_id(&sb, msg_id_info[id].id_string);
 220
 221         va_start(ap, fmt);
 222         strbuf_vaddf(&sb, fmt, ap);
 223         result = options->error_func(object, msg_type, sb.buf);
 224         strbuf_release(&sb);
 225         va_end(ap);
 226
 227         return result;
 228 }
 229
 230 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 231 {
 232         struct tree_desc desc;
 233         struct name_entry entry;
 234         int res = 0;
 235
 236         if (parse_tree(tree))
 237                 return -1;
 238
 239         init_tree_desc(&desc, tree->buffer, tree->size);
 240         while (tree_entry(&desc, &entry)) {
 241                 int result;
 242
 243                 if (S_ISGITLINK(entry.mode))
 244                         continue;
 245                 if (S_ISDIR(entry.mode))
 246                         result = options->walk(&lookup_tree(entry.sha1)->object, OBJ_TREE, data, options);
 247                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode))
 248                         result = options->walk(&lookup_blob(entry.sha1)->object, OBJ_BLOB, data, options);
 249                 else {
 250                         result = error("in tree %s: entry %s has bad mode %.6o",
 251                                         sha1_to_hex(tree->object.sha1), entry.path, entry.mode);
 252                 }
 253                 if (result < 0)
 254                         return result;
 255                 if (!res)
 256                         res = result;
 257         }
 258         return res;
 259 }
 260
 261 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 262 {
 263         struct commit_list *parents;
 264         int res;
 265         int result;
 266
 267         if (parse_commit(commit))
 268                 return -1;
 269
 270         result = options->walk((struct object *)commit->tree, OBJ_TREE, data, options);
 271         if (result < 0)
 272                 return result;
 273         res = result;
 274
 275         parents = commit->parents;
 276         while (parents) {
 277                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 278                 if (result < 0)
 279                         return result;
 280                 if (!res)
 281                         res = result;
 282                 parents = parents->next;
 283         }
 284         return res;
 285 }
 286
 287 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 288 {
 289         if (parse_tag(tag))
 290                 return -1;
 291         return options->walk(tag->tagged, OBJ_ANY, data, options);
 292 }
 293
 294 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 295 {
 296         if (!obj)
 297                 return -1;
 298         switch (obj->type) {
 299         case OBJ_BLOB:
 300                 return 0;
 301         case OBJ_TREE:
 302                 return fsck_walk_tree((struct tree *)obj, data, options);
 303         case OBJ_COMMIT:
 304                 return fsck_walk_commit((struct commit *)obj, data, options);
 305         case OBJ_TAG:
 306                 return fsck_walk_tag((struct tag *)obj, data, options);
 307         default:
 308                 error("Unknown object type for %s", sha1_to_hex(obj->sha1));
 309                 return -1;
 310         }
 311 }
 312
 313 /*
 314  * The entries in a tree are ordered in the _path_ order,
 315  * which means that a directory entry is ordered by adding
 316  * a slash to the end of it.
 317  *
 318  * So a directory called "a" is ordered _after_ a file
 319  * called "a.c", because "a/" sorts after "a.c".
 320  */
 321 #define TREE_UNORDERED (-1)
 322 #define TREE_HAS_DUPS  (-2)
 323
 324 static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 325 {
 326         int len1 = strlen(name1);
 327         int len2 = strlen(name2);
 328         int len = len1 < len2 ? len1 : len2;
 329         unsigned char c1, c2;
 330         int cmp;
 331
 332         cmp = memcmp(name1, name2, len);
 333         if (cmp < 0)
 334                 return 0;
 335         if (cmp > 0)
 336                 return TREE_UNORDERED;
 337
 338         /*
 339          * Ok, the first <len> characters are the same.
 340          * Now we need to order the next one, but turn
 341          * a '\0' into a '/' for a directory entry.
 342          */
 343         c1 = name1[len];
 344         c2 = name2[len];
 345         if (!c1 && !c2)
 346                 /*
 347                  * git-write-tree used to write out a nonsense tree that has
 348                  * entries with the same name, one blob and one tree.  Make
 349                  * sure we do not have duplicate entries.
 350                  */
 351                 return TREE_HAS_DUPS;
 352         if (!c1 && S_ISDIR(mode1))
 353                 c1 = '/';
 354         if (!c2 && S_ISDIR(mode2))
 355                 c2 = '/';
 356         return c1 < c2 ? 0 : TREE_UNORDERED;
 357 }
 358
 359 static int fsck_tree(struct tree *item, struct fsck_options *options)
 360 {
 361         int retval;
 362         int has_null_sha1 = 0;
 363         int has_full_path = 0;
 364         int has_empty_name = 0;
 365         int has_dot = 0;
 366         int has_dotdot = 0;
 367         int has_dotgit = 0;
 368         int has_zero_pad = 0;
 369         int has_bad_modes = 0;
 370         int has_dup_entries = 0;
 371         int not_properly_sorted = 0;
 372         struct tree_desc desc;
 373         unsigned o_mode;
 374         const char *o_name;
 375
 376         init_tree_desc(&desc, item->buffer, item->size);
 377
 378         o_mode = 0;
 379         o_name = NULL;
 380
 381         while (desc.size) {
 382                 unsigned mode;
 383                 const char *name;
 384                 const unsigned char *sha1;
 385
 386                 sha1 = tree_entry_extract(&desc, &name, &mode);
 387
 388                 has_null_sha1 |= is_null_sha1(sha1);
 389                 has_full_path |= !!strchr(name, '/');
 390                 has_empty_name |= !*name;
 391                 has_dot |= !strcmp(name, ".");
 392                 has_dotdot |= !strcmp(name, "..");
 393                 has_dotgit |= (!strcmp(name, ".git") ||
 394                                is_hfs_dotgit(name) ||
 395                                is_ntfs_dotgit(name));
 396                 has_zero_pad |= *(char *)desc.buffer == '0';
 397                 update_tree_entry(&desc);
 398
 399                 switch (mode) {
 400                 /*
 401                  * Standard modes..
 402                  */
 403                 case S_IFREG | 0755:
 404                 case S_IFREG | 0644:
 405                 case S_IFLNK:
 406                 case S_IFDIR:
 407                 case S_IFGITLINK:
 408                         break;
 409                 /*
 410                  * This is nonstandard, but we had a few of these
 411                  * early on when we honored the full set of mode
 412                  * bits..
 413                  */
 414                 case S_IFREG | 0664:
 415                         if (!options->strict)
 416                                 break;
 417                 default:
 418                         has_bad_modes = 1;
 419                 }
 420
 421                 if (o_name) {
 422                         switch (verify_ordered(o_mode, o_name, mode, name)) {
 423                         case TREE_UNORDERED:
 424                                 not_properly_sorted = 1;
 425                                 break;
 426                         case TREE_HAS_DUPS:
 427                                 has_dup_entries = 1;
 428                                 break;
 429                         default:
 430                                 break;
 431                         }
 432                 }
 433
 434                 o_mode = mode;
 435                 o_name = name;
 436         }
 437
 438         retval = 0;
 439         if (has_null_sha1)
 440                 retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 441         if (has_full_path)
 442                 retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 443         if (has_empty_name)
 444                 retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 445         if (has_dot)
 446                 retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 447         if (has_dotdot)
 448                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 449         if (has_dotgit)
 450                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 451         if (has_zero_pad)
 452                 retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 453         if (has_bad_modes)
 454                 retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 455         if (has_dup_entries)
 456                 retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 457         if (not_properly_sorted)
 458                 retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 459         return retval;
 460 }
 461
 462 static int require_end_of_header(const void *data, unsigned long size,
 463         struct object *obj, struct fsck_options *options)
 464 {
 465         const char *buffer = (const char *)data;
 466         unsigned long i;
 467
 468         for (i = 0; i < size; i++) {
 469                 switch (buffer[i]) {
 470                 case '\0':
 471                         return report(options, obj,
 472                                 FSCK_MSG_NUL_IN_HEADER,
 473                                 "unterminated header: NUL at offset %ld", i);
 474                 case '\n':
 475                         if (i + 1 < size && buffer[i + 1] == '\n')
 476                                 return 0;
 477                 }
 478         }
 479
 480         return report(options, obj,
 481                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 482 }
 483
 484 static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 485 {
 486         const char *p = *ident;
 487         char *end;
 488
 489         *ident = strchrnul(*ident, '\n');
 490         if (**ident == '\n')
 491                 (*ident)++;
 492
 493         if (*p == '<')
 494                 return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 495         p += strcspn(p, "<>\n");
 496         if (*p == '>')
 497                 return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 498         if (*p != '<')
 499                 return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 500         if (p[-1] != ' ')
 501                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 502         p++;
 503         p += strcspn(p, "<>\n");
 504         if (*p != '>')
 505                 return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 506         p++;
 507         if (*p != ' ')
 508                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 509         p++;
 510         if (*p == '0' && p[1] != ' ')
 511                 return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 512         if (date_overflows(strtoul(p, &end, 10)))
 513                 return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 514         if ((end == p || *end != ' '))
 515                 return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 516         p = end + 1;
 517         if ((*p != '+' && *p != '-') ||
 518             !isdigit(p[1]) ||
 519             !isdigit(p[2]) ||
 520             !isdigit(p[3]) ||
 521             !isdigit(p[4]) ||
 522             (p[5] != '\n'))
 523                 return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 524         p += 6;
 525         return 0;
 526 }
 527
 528 static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 529         unsigned long size, struct fsck_options *options)
 530 {
 531         unsigned char tree_sha1[20], sha1[20];
 532         struct commit_graft *graft;
 533         unsigned parent_count, parent_line_count = 0, author_count;
 534         int err;
 535
 536         if (require_end_of_header(buffer, size, &commit->object, options))
 537                 return -1;
 538
 539         if (!skip_prefix(buffer, "tree ", &buffer))
 540                 return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 541         if (get_sha1_hex(buffer, tree_sha1) || buffer[40] != '\n') {
 542                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 543                 if (err)
 544                         return err;
 545         }
 546         buffer += 41;
 547         while (skip_prefix(buffer, "parent ", &buffer)) {
 548                 if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 549                         err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 550                         if (err)
 551                                 return err;
 552                 }
 553                 buffer += 41;
 554                 parent_line_count++;
 555         }
 556         graft = lookup_commit_graft(commit->object.sha1);
 557         parent_count = commit_list_count(commit->parents);
 558         if (graft) {
 559                 if (graft->nr_parent == -1 && !parent_count)
 560                         ; /* shallow commit */
 561                 else if (graft->nr_parent != parent_count) {
 562                         err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 563                         if (err)
 564                                 return err;
 565                 }
 566         } else {
 567                 if (parent_count != parent_line_count) {
 568                         err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 569                         if (err)
 570                                 return err;
 571                 }
 572         }
 573         author_count = 0;
 574         while (skip_prefix(buffer, "author ", &buffer)) {
 575                 author_count++;
 576                 err = fsck_ident(&buffer, &commit->object, options);
 577                 if (err)
 578                         return err;
 579         }
 580         if (author_count < 1)
 581                 err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 582         else if (author_count > 1)
 583                 err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 584         if (err)
 585                 return err;
 586         if (!skip_prefix(buffer, "committer ", &buffer))
 587                 return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 588         err = fsck_ident(&buffer, &commit->object, options);
 589         if (err)
 590                 return err;
 591         if (!commit->tree)
 592                 return report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", sha1_to_hex(tree_sha1));
 593
 594         return 0;
 595 }
 596
 597 static int fsck_commit(struct commit *commit, const char *data,
 598         unsigned long size, struct fsck_options *options)
 599 {
 600         const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 601         int ret = fsck_commit_buffer(commit, buffer, size, options);
 602         if (!data)
 603                 unuse_commit_buffer(commit, buffer);
 604         return ret;
 605 }
 606
 607 static int fsck_tag_buffer(struct tag *tag, const char *data,
 608         unsigned long size, struct fsck_options *options)
 609 {
 610         unsigned char sha1[20];
 611         int ret = 0;
 612         const char *buffer;
 613         char *to_free = NULL, *eol;
 614         struct strbuf sb = STRBUF_INIT;
 615
 616         if (data)
 617                 buffer = data;
 618         else {
 619                 enum object_type type;
 620
 621                 buffer = to_free =
 622                         read_sha1_file(tag->object.sha1, &type, &size);
 623                 if (!buffer)
 624                         return report(options, &tag->object,
 625                                 FSCK_MSG_MISSING_TAG_OBJECT,
 626                                 "cannot read tag object");
 627
 628                 if (type != OBJ_TAG) {
 629                         ret = report(options, &tag->object,
 630                                 FSCK_MSG_TAG_OBJECT_NOT_TAG,
 631                                 "expected tag got %s",
 632                             typename(type));
 633                         goto done;
 634                 }
 635         }
 636
 637         if (require_end_of_header(buffer, size, &tag->object, options))
 638                 goto done;
 639
 640         if (!skip_prefix(buffer, "object ", &buffer)) {
 641                 ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 642                 goto done;
 643         }
 644         if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 645                 ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 646                 if (ret)
 647                         goto done;
 648         }
 649         buffer += 41;
 650
 651         if (!skip_prefix(buffer, "type ", &buffer)) {
 652                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 653                 goto done;
 654         }
 655         eol = strchr(buffer, '\n');
 656         if (!eol) {
 657                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 658                 goto done;
 659         }
 660         if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 661                 ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 662         if (ret)
 663                 goto done;
 664         buffer = eol + 1;
 665
 666         if (!skip_prefix(buffer, "tag ", &buffer)) {
 667                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 668                 goto done;
 669         }
 670         eol = strchr(buffer, '\n');
 671         if (!eol) {
 672                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 673                 goto done;
 674         }
 675         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 676         if (check_refname_format(sb.buf, 0))
 677                 report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 678                            "invalid 'tag' name: %.*s",
 679                            (int)(eol - buffer), buffer);
 680         buffer = eol + 1;
 681
 682         if (!skip_prefix(buffer, "tagger ", &buffer))
 683                 /* early tags do not contain 'tagger' lines; warn only */
 684                 report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 685         else
 686                 ret = fsck_ident(&buffer, &tag->object, options);
 687
 688 done:
 689         strbuf_release(&sb);
 690         free(to_free);
 691         return ret;
 692 }
 693
 694 static int fsck_tag(struct tag *tag, const char *data,
 695         unsigned long size, struct fsck_options *options)
 696 {
 697         struct object *tagged = tag->tagged;
 698
 699         if (!tagged)
 700                 return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 701
 702         return fsck_tag_buffer(tag, data, size, options);
 703 }
 704
 705 int fsck_object(struct object *obj, void *data, unsigned long size,
 706         struct fsck_options *options)
 707 {
 708         if (!obj)
 709                 return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
 710
 711         if (obj->type == OBJ_BLOB)
 712                 return 0;
 713         if (obj->type == OBJ_TREE)
 714                 return fsck_tree((struct tree *) obj, options);
 715         if (obj->type == OBJ_COMMIT)
 716                 return fsck_commit((struct commit *) obj, (const char *) data,
 717                         size, options);
 718         if (obj->type == OBJ_TAG)
 719                 return fsck_tag((struct tag *) obj, (const char *) data,
 720                         size, options);
 721
 722         return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
 723                           obj->type);
 724 }
 725
 726 int fsck_error_function(struct object *obj, int msg_type, const char *message)
 727 {
 728         if (msg_type == FSCK_WARN) {
 729                 warning("object %s: %s", sha1_to_hex(obj->sha1), message);
 730                 return 0;
 731         }
 732         error("object %s: %s", sha1_to_hex(obj->sha1), message);
 733         return 1;
 734 }