fsck.c

   1 #include "cache.h"
   2 #include "object-store.h"
   3 #include "repository.h"
   4 #include "object.h"
   5 #include "blob.h"
   6 #include "tree.h"
   7 #include "tree-walk.h"
   8 #include "commit.h"
   9 #include "tag.h"
  10 #include "fsck.h"
  11 #include "refs.h"
  12 #include "utf8.h"
  13 #include "sha1-array.h"
  14 #include "decorate.h"
  15 #include "oidset.h"
  16 #include "packfile.h"
  17 #include "submodule-config.h"
  18 #include "config.h"
  19 #include "help.h"
  20
  21 static struct oidset gitmodules_found = OIDSET_INIT;
  22 static struct oidset gitmodules_done = OIDSET_INIT;
  23
  24 #define FSCK_FATAL -1
  25 #define FSCK_INFO -2
  26
  27 #define FOREACH_MSG_ID(FUNC) \
  28         /* fatal errors */ \
  29         FUNC(NUL_IN_HEADER, FATAL) \
  30         FUNC(UNTERMINATED_HEADER, FATAL) \
  31         /* errors */ \
  32         FUNC(BAD_DATE, ERROR) \
  33         FUNC(BAD_DATE_OVERFLOW, ERROR) \
  34         FUNC(BAD_EMAIL, ERROR) \
  35         FUNC(BAD_NAME, ERROR) \
  36         FUNC(BAD_OBJECT_SHA1, ERROR) \
  37         FUNC(BAD_PARENT_SHA1, ERROR) \
  38         FUNC(BAD_TAG_OBJECT, ERROR) \
  39         FUNC(BAD_TIMEZONE, ERROR) \
  40         FUNC(BAD_TREE, ERROR) \
  41         FUNC(BAD_TREE_SHA1, ERROR) \
  42         FUNC(BAD_TYPE, ERROR) \
  43         FUNC(DUPLICATE_ENTRIES, ERROR) \
  44         FUNC(MISSING_AUTHOR, ERROR) \
  45         FUNC(MISSING_COMMITTER, ERROR) \
  46         FUNC(MISSING_EMAIL, ERROR) \
  47         FUNC(MISSING_GRAFT, ERROR) \
  48         FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  49         FUNC(MISSING_OBJECT, ERROR) \
  50         FUNC(MISSING_PARENT, ERROR) \
  51         FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  52         FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  53         FUNC(MISSING_TAG, ERROR) \
  54         FUNC(MISSING_TAG_ENTRY, ERROR) \
  55         FUNC(MISSING_TAG_OBJECT, ERROR) \
  56         FUNC(MISSING_TREE, ERROR) \
  57         FUNC(MISSING_TREE_OBJECT, ERROR) \
  58         FUNC(MISSING_TYPE, ERROR) \
  59         FUNC(MISSING_TYPE_ENTRY, ERROR) \
  60         FUNC(MULTIPLE_AUTHORS, ERROR) \
  61         FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
  62         FUNC(TREE_NOT_SORTED, ERROR) \
  63         FUNC(UNKNOWN_TYPE, ERROR) \
  64         FUNC(ZERO_PADDED_DATE, ERROR) \
  65         FUNC(GITMODULES_MISSING, ERROR) \
  66         FUNC(GITMODULES_BLOB, ERROR) \
  67         FUNC(GITMODULES_PARSE, ERROR) \
  68         FUNC(GITMODULES_NAME, ERROR) \
  69         FUNC(GITMODULES_SYMLINK, ERROR) \
  70         /* warnings */ \
  71         FUNC(BAD_FILEMODE, WARN) \
  72         FUNC(EMPTY_NAME, WARN) \
  73         FUNC(FULL_PATHNAME, WARN) \
  74         FUNC(HAS_DOT, WARN) \
  75         FUNC(HAS_DOTDOT, WARN) \
  76         FUNC(HAS_DOTGIT, WARN) \
  77         FUNC(NULL_SHA1, WARN) \
  78         FUNC(ZERO_PADDED_FILEMODE, WARN) \
  79         FUNC(NUL_IN_COMMIT, WARN) \
  80         /* infos (reported as warnings, but ignored by default) */ \
  81         FUNC(BAD_TAG_NAME, INFO) \
  82         FUNC(MISSING_TAGGER_ENTRY, INFO)
  83
  84 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
  85 enum fsck_msg_id {
  86         FOREACH_MSG_ID(MSG_ID)
  87         FSCK_MSG_MAX
  88 };
  89 #undef MSG_ID
  90
  91 #define STR(x) #x
  92 #define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
  93 static struct {
  94         const char *id_string;
  95         const char *downcased;
  96         const char *camelcased;
  97         int msg_type;
  98 } msg_id_info[FSCK_MSG_MAX + 1] = {
  99         FOREACH_MSG_ID(MSG_ID)
 100         { NULL, NULL, NULL, -1 }
 101 };
 102 #undef MSG_ID
 103
 104 static void prepare_msg_ids(void)
 105 {
 106         int i;
 107
 108         if (msg_id_info[0].downcased)
 109                 return;
 110
 111         /* convert id_string to lower case, without underscores. */
 112         for (i = 0; i < FSCK_MSG_MAX; i++) {
 113                 const char *p = msg_id_info[i].id_string;
 114                 int len = strlen(p);
 115                 char *q = xmalloc(len);
 116
 117                 msg_id_info[i].downcased = q;
 118                 while (*p)
 119                         if (*p == '_')
 120                                 p++;
 121                         else
 122                                 *(q)++ = tolower(*(p)++);
 123                 *q = '\0';
 124
 125                 p = msg_id_info[i].id_string;
 126                 q = xmalloc(len);
 127                 msg_id_info[i].camelcased = q;
 128                 while (*p) {
 129                         if (*p == '_') {
 130                                 p++;
 131                                 if (*p)
 132                                         *q++ = *p++;
 133                         } else {
 134                                 *q++ = tolower(*p++);
 135                         }
 136                 }
 137                 *q = '\0';
 138         }
 139 }
 140
 141 static int parse_msg_id(const char *text)
 142 {
 143         int i;
 144
 145         prepare_msg_ids();
 146
 147         for (i = 0; i < FSCK_MSG_MAX; i++)
 148                 if (!strcmp(text, msg_id_info[i].downcased))
 149                         return i;
 150
 151         return -1;
 152 }
 153
 154 void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
 155 {
 156         int i;
 157
 158         prepare_msg_ids();
 159
 160         for (i = 0; i < FSCK_MSG_MAX; i++)
 161                 list_config_item(list, prefix, msg_id_info[i].camelcased);
 162 }
 163
 164 static int fsck_msg_type(enum fsck_msg_id msg_id,
 165         struct fsck_options *options)
 166 {
 167         int msg_type;
 168
 169         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 170
 171         if (options->msg_type)
 172                 msg_type = options->msg_type[msg_id];
 173         else {
 174                 msg_type = msg_id_info[msg_id].msg_type;
 175                 if (options->strict && msg_type == FSCK_WARN)
 176                         msg_type = FSCK_ERROR;
 177         }
 178
 179         return msg_type;
 180 }
 181
 182 static void init_skiplist(struct fsck_options *options, const char *path)
 183 {
 184         static struct oid_array skiplist = OID_ARRAY_INIT;
 185         int sorted, fd;
 186         char buffer[GIT_MAX_HEXSZ + 1];
 187         struct object_id oid;
 188
 189         if (options->skiplist)
 190                 sorted = options->skiplist->sorted;
 191         else {
 192                 sorted = 1;
 193                 options->skiplist = &skiplist;
 194         }
 195
 196         fd = open(path, O_RDONLY);
 197         if (fd < 0)
 198                 die("Could not open skip list: %s", path);
 199         for (;;) {
 200                 const char *p;
 201                 int result = read_in_full(fd, buffer, sizeof(buffer));
 202                 if (result < 0)
 203                         die_errno("Could not read '%s'", path);
 204                 if (!result)
 205                         break;
 206                 if (parse_oid_hex(buffer, &oid, &p) || *p != '\n')
 207                         die("Invalid SHA-1: %s", buffer);
 208                 oid_array_append(&skiplist, &oid);
 209                 if (sorted && skiplist.nr > 1 &&
 210                                 oidcmp(&skiplist.oid[skiplist.nr - 2],
 211                                        &oid) > 0)
 212                         sorted = 0;
 213         }
 214         close(fd);
 215
 216         if (sorted)
 217                 skiplist.sorted = 1;
 218 }
 219
 220 static int parse_msg_type(const char *str)
 221 {
 222         if (!strcmp(str, "error"))
 223                 return FSCK_ERROR;
 224         else if (!strcmp(str, "warn"))
 225                 return FSCK_WARN;
 226         else if (!strcmp(str, "ignore"))
 227                 return FSCK_IGNORE;
 228         else
 229                 die("Unknown fsck message type: '%s'", str);
 230 }
 231
 232 int is_valid_msg_type(const char *msg_id, const char *msg_type)
 233 {
 234         if (parse_msg_id(msg_id) < 0)
 235                 return 0;
 236         parse_msg_type(msg_type);
 237         return 1;
 238 }
 239
 240 void fsck_set_msg_type(struct fsck_options *options,
 241                 const char *msg_id, const char *msg_type)
 242 {
 243         int id = parse_msg_id(msg_id), type;
 244
 245         if (id < 0)
 246                 die("Unhandled message id: %s", msg_id);
 247         type = parse_msg_type(msg_type);
 248
 249         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
 250                 die("Cannot demote %s to %s", msg_id, msg_type);
 251
 252         if (!options->msg_type) {
 253                 int i;
 254                 int *msg_type;
 255                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
 256                 for (i = 0; i < FSCK_MSG_MAX; i++)
 257                         msg_type[i] = fsck_msg_type(i, options);
 258                 options->msg_type = msg_type;
 259         }
 260
 261         options->msg_type[id] = type;
 262 }
 263
 264 void fsck_set_msg_types(struct fsck_options *options, const char *values)
 265 {
 266         char *buf = xstrdup(values), *to_free = buf;
 267         int done = 0;
 268
 269         while (!done) {
 270                 int len = strcspn(buf, " ,|"), equal;
 271
 272                 done = !buf[len];
 273                 if (!len) {
 274                         buf++;
 275                         continue;
 276                 }
 277                 buf[len] = '\0';
 278
 279                 for (equal = 0;
 280                      equal < len && buf[equal] != '=' && buf[equal] != ':';
 281                      equal++)
 282                         buf[equal] = tolower(buf[equal]);
 283                 buf[equal] = '\0';
 284
 285                 if (!strcmp(buf, "skiplist")) {
 286                         if (equal == len)
 287                                 die("skiplist requires a path");
 288                         init_skiplist(options, buf + equal + 1);
 289                         buf += len + 1;
 290                         continue;
 291                 }
 292
 293                 if (equal == len)
 294                         die("Missing '=': '%s'", buf);
 295
 296                 fsck_set_msg_type(options, buf, buf + equal + 1);
 297                 buf += len + 1;
 298         }
 299         free(to_free);
 300 }
 301
 302 static void append_msg_id(struct strbuf *sb, const char *msg_id)
 303 {
 304         for (;;) {
 305                 char c = *(msg_id)++;
 306
 307                 if (!c)
 308                         break;
 309                 if (c != '_')
 310                         strbuf_addch(sb, tolower(c));
 311                 else {
 312                         assert(*msg_id);
 313                         strbuf_addch(sb, *(msg_id)++);
 314                 }
 315         }
 316
 317         strbuf_addstr(sb, ": ");
 318 }
 319
 320 __attribute__((format (printf, 4, 5)))
 321 static int report(struct fsck_options *options, struct object *object,
 322         enum fsck_msg_id id, const char *fmt, ...)
 323 {
 324         va_list ap;
 325         struct strbuf sb = STRBUF_INIT;
 326         int msg_type = fsck_msg_type(id, options), result;
 327
 328         if (msg_type == FSCK_IGNORE)
 329                 return 0;
 330
 331         if (options->skiplist && object &&
 332                         oid_array_lookup(options->skiplist, &object->oid) >= 0)
 333                 return 0;
 334
 335         if (msg_type == FSCK_FATAL)
 336                 msg_type = FSCK_ERROR;
 337         else if (msg_type == FSCK_INFO)
 338                 msg_type = FSCK_WARN;
 339
 340         append_msg_id(&sb, msg_id_info[id].id_string);
 341
 342         va_start(ap, fmt);
 343         strbuf_vaddf(&sb, fmt, ap);
 344         result = options->error_func(options, object, msg_type, sb.buf);
 345         strbuf_release(&sb);
 346         va_end(ap);
 347
 348         return result;
 349 }
 350
 351 static char *get_object_name(struct fsck_options *options, struct object *obj)
 352 {
 353         if (!options->object_names)
 354                 return NULL;
 355         return lookup_decoration(options->object_names, obj);
 356 }
 357
 358 static void put_object_name(struct fsck_options *options, struct object *obj,
 359         const char *fmt, ...)
 360 {
 361         va_list ap;
 362         struct strbuf buf = STRBUF_INIT;
 363         char *existing;
 364
 365         if (!options->object_names)
 366                 return;
 367         existing = lookup_decoration(options->object_names, obj);
 368         if (existing)
 369                 return;
 370         va_start(ap, fmt);
 371         strbuf_vaddf(&buf, fmt, ap);
 372         add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
 373         va_end(ap);
 374 }
 375
 376 static const char *describe_object(struct fsck_options *o, struct object *obj)
 377 {
 378         static struct strbuf buf = STRBUF_INIT;
 379         char *name;
 380
 381         strbuf_reset(&buf);
 382         strbuf_addstr(&buf, oid_to_hex(&obj->oid));
 383         if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
 384                 strbuf_addf(&buf, " (%s)", name);
 385
 386         return buf.buf;
 387 }
 388
 389 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 390 {
 391         struct tree_desc desc;
 392         struct name_entry entry;
 393         int res = 0;
 394         const char *name;
 395
 396         if (parse_tree(tree))
 397                 return -1;
 398
 399         name = get_object_name(options, &tree->object);
 400         if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
 401                 return -1;
 402         while (tree_entry_gently(&desc, &entry)) {
 403                 struct object *obj;
 404                 int result;
 405
 406                 if (S_ISGITLINK(entry.mode))
 407                         continue;
 408
 409                 if (S_ISDIR(entry.mode)) {
 410                         obj = (struct object *)lookup_tree(entry.oid);
 411                         if (name && obj)
 412                                 put_object_name(options, obj, "%s%s/", name,
 413                                         entry.path);
 414                         result = options->walk(obj, OBJ_TREE, data, options);
 415                 }
 416                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
 417                         obj = (struct object *)lookup_blob(entry.oid);
 418                         if (name && obj)
 419                                 put_object_name(options, obj, "%s%s", name,
 420                                         entry.path);
 421                         result = options->walk(obj, OBJ_BLOB, data, options);
 422                 }
 423                 else {
 424                         result = error("in tree %s: entry %s has bad mode %.6o",
 425                                         describe_object(options, &tree->object), entry.path, entry.mode);
 426                 }
 427                 if (result < 0)
 428                         return result;
 429                 if (!res)
 430                         res = result;
 431         }
 432         return res;
 433 }
 434
 435 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 436 {
 437         int counter = 0, generation = 0, name_prefix_len = 0;
 438         struct commit_list *parents;
 439         int res;
 440         int result;
 441         const char *name;
 442
 443         if (parse_commit(commit))
 444                 return -1;
 445
 446         name = get_object_name(options, &commit->object);
 447         if (name)
 448                 put_object_name(options, &get_commit_tree(commit)->object,
 449                                 "%s:", name);
 450
 451         result = options->walk((struct object *)get_commit_tree(commit),
 452                                OBJ_TREE, data, options);
 453         if (result < 0)
 454                 return result;
 455         res = result;
 456
 457         parents = commit->parents;
 458         if (name && parents) {
 459                 int len = strlen(name), power;
 460
 461                 if (len && name[len - 1] == '^') {
 462                         generation = 1;
 463                         name_prefix_len = len - 1;
 464                 }
 465                 else { /* parse ~<generation> suffix */
 466                         for (generation = 0, power = 1;
 467                              len && isdigit(name[len - 1]);
 468                              power *= 10)
 469                                 generation += power * (name[--len] - '0');
 470                         if (power > 1 && len && name[len - 1] == '~')
 471                                 name_prefix_len = len - 1;
 472                 }
 473         }
 474
 475         while (parents) {
 476                 if (name) {
 477                         struct object *obj = &parents->item->object;
 478
 479                         if (++counter > 1)
 480                                 put_object_name(options, obj, "%s^%d",
 481                                         name, counter);
 482                         else if (generation > 0)
 483                                 put_object_name(options, obj, "%.*s~%d",
 484                                         name_prefix_len, name, generation + 1);
 485                         else
 486                                 put_object_name(options, obj, "%s^", name);
 487                 }
 488                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 489                 if (result < 0)
 490                         return result;
 491                 if (!res)
 492                         res = result;
 493                 parents = parents->next;
 494         }
 495         return res;
 496 }
 497
 498 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 499 {
 500         char *name = get_object_name(options, &tag->object);
 501
 502         if (parse_tag(tag))
 503                 return -1;
 504         if (name)
 505                 put_object_name(options, tag->tagged, "%s", name);
 506         return options->walk(tag->tagged, OBJ_ANY, data, options);
 507 }
 508
 509 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 510 {
 511         if (!obj)
 512                 return -1;
 513
 514         if (obj->type == OBJ_NONE)
 515                 parse_object(the_repository, &obj->oid);
 516
 517         switch (obj->type) {
 518         case OBJ_BLOB:
 519                 return 0;
 520         case OBJ_TREE:
 521                 return fsck_walk_tree((struct tree *)obj, data, options);
 522         case OBJ_COMMIT:
 523                 return fsck_walk_commit((struct commit *)obj, data, options);
 524         case OBJ_TAG:
 525                 return fsck_walk_tag((struct tag *)obj, data, options);
 526         default:
 527                 error("Unknown object type for %s", describe_object(options, obj));
 528                 return -1;
 529         }
 530 }
 531
 532 /*
 533  * The entries in a tree are ordered in the _path_ order,
 534  * which means that a directory entry is ordered by adding
 535  * a slash to the end of it.
 536  *
 537  * So a directory called "a" is ordered _after_ a file
 538  * called "a.c", because "a/" sorts after "a.c".
 539  */
 540 #define TREE_UNORDERED (-1)
 541 #define TREE_HAS_DUPS  (-2)
 542
 543 static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 544 {
 545         int len1 = strlen(name1);
 546         int len2 = strlen(name2);
 547         int len = len1 < len2 ? len1 : len2;
 548         unsigned char c1, c2;
 549         int cmp;
 550
 551         cmp = memcmp(name1, name2, len);
 552         if (cmp < 0)
 553                 return 0;
 554         if (cmp > 0)
 555                 return TREE_UNORDERED;
 556
 557         /*
 558          * Ok, the first <len> characters are the same.
 559          * Now we need to order the next one, but turn
 560          * a '\0' into a '/' for a directory entry.
 561          */
 562         c1 = name1[len];
 563         c2 = name2[len];
 564         if (!c1 && !c2)
 565                 /*
 566                  * git-write-tree used to write out a nonsense tree that has
 567                  * entries with the same name, one blob and one tree.  Make
 568                  * sure we do not have duplicate entries.
 569                  */
 570                 return TREE_HAS_DUPS;
 571         if (!c1 && S_ISDIR(mode1))
 572                 c1 = '/';
 573         if (!c2 && S_ISDIR(mode2))
 574                 c2 = '/';
 575         return c1 < c2 ? 0 : TREE_UNORDERED;
 576 }
 577
 578 static int fsck_tree(struct tree *item, struct fsck_options *options)
 579 {
 580         int retval = 0;
 581         int has_null_sha1 = 0;
 582         int has_full_path = 0;
 583         int has_empty_name = 0;
 584         int has_dot = 0;
 585         int has_dotdot = 0;
 586         int has_dotgit = 0;
 587         int has_zero_pad = 0;
 588         int has_bad_modes = 0;
 589         int has_dup_entries = 0;
 590         int not_properly_sorted = 0;
 591         struct tree_desc desc;
 592         unsigned o_mode;
 593         const char *o_name;
 594
 595         if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
 596                 retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 597                 return retval;
 598         }
 599
 600         o_mode = 0;
 601         o_name = NULL;
 602
 603         while (desc.size) {
 604                 unsigned mode;
 605                 const char *name;
 606                 const struct object_id *oid;
 607
 608                 oid = tree_entry_extract(&desc, &name, &mode);
 609
 610                 has_null_sha1 |= is_null_oid(oid);
 611                 has_full_path |= !!strchr(name, '/');
 612                 has_empty_name |= !*name;
 613                 has_dot |= !strcmp(name, ".");
 614                 has_dotdot |= !strcmp(name, "..");
 615                 has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
 616                 has_zero_pad |= *(char *)desc.buffer == '0';
 617
 618                 if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
 619                         if (!S_ISLNK(mode))
 620                                 oidset_insert(&gitmodules_found, oid);
 621                         else
 622                                 retval += report(options, &item->object,
 623                                                  FSCK_MSG_GITMODULES_SYMLINK,
 624                                                  ".gitmodules is a symbolic link");
 625                 }
 626
 627                 if (update_tree_entry_gently(&desc)) {
 628                         retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 629                         break;
 630                 }
 631
 632                 switch (mode) {
 633                 /*
 634                  * Standard modes..
 635                  */
 636                 case S_IFREG | 0755:
 637                 case S_IFREG | 0644:
 638                 case S_IFLNK:
 639                 case S_IFDIR:
 640                 case S_IFGITLINK:
 641                         break;
 642                 /*
 643                  * This is nonstandard, but we had a few of these
 644                  * early on when we honored the full set of mode
 645                  * bits..
 646                  */
 647                 case S_IFREG | 0664:
 648                         if (!options->strict)
 649                                 break;
 650                         /* fallthrough */
 651                 default:
 652                         has_bad_modes = 1;
 653                 }
 654
 655                 if (o_name) {
 656                         switch (verify_ordered(o_mode, o_name, mode, name)) {
 657                         case TREE_UNORDERED:
 658                                 not_properly_sorted = 1;
 659                                 break;
 660                         case TREE_HAS_DUPS:
 661                                 has_dup_entries = 1;
 662                                 break;
 663                         default:
 664                                 break;
 665                         }
 666                 }
 667
 668                 o_mode = mode;
 669                 o_name = name;
 670         }
 671
 672         if (has_null_sha1)
 673                 retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 674         if (has_full_path)
 675                 retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 676         if (has_empty_name)
 677                 retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 678         if (has_dot)
 679                 retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 680         if (has_dotdot)
 681                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 682         if (has_dotgit)
 683                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 684         if (has_zero_pad)
 685                 retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 686         if (has_bad_modes)
 687                 retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 688         if (has_dup_entries)
 689                 retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 690         if (not_properly_sorted)
 691                 retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 692         return retval;
 693 }
 694
 695 static int verify_headers(const void *data, unsigned long size,
 696                           struct object *obj, struct fsck_options *options)
 697 {
 698         const char *buffer = (const char *)data;
 699         unsigned long i;
 700
 701         for (i = 0; i < size; i++) {
 702                 switch (buffer[i]) {
 703                 case '\0':
 704                         return report(options, obj,
 705                                 FSCK_MSG_NUL_IN_HEADER,
 706                                 "unterminated header: NUL at offset %ld", i);
 707                 case '\n':
 708                         if (i + 1 < size && buffer[i + 1] == '\n')
 709                                 return 0;
 710                 }
 711         }
 712
 713         /*
 714          * We did not find double-LF that separates the header
 715          * and the body.  Not having a body is not a crime but
 716          * we do want to see the terminating LF for the last header
 717          * line.
 718          */
 719         if (size && buffer[size - 1] == '\n')
 720                 return 0;
 721
 722         return report(options, obj,
 723                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 724 }
 725
 726 static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 727 {
 728         const char *p = *ident;
 729         char *end;
 730
 731         *ident = strchrnul(*ident, '\n');
 732         if (**ident == '\n')
 733                 (*ident)++;
 734
 735         if (*p == '<')
 736                 return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 737         p += strcspn(p, "<>\n");
 738         if (*p == '>')
 739                 return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 740         if (*p != '<')
 741                 return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 742         if (p[-1] != ' ')
 743                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 744         p++;
 745         p += strcspn(p, "<>\n");
 746         if (*p != '>')
 747                 return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 748         p++;
 749         if (*p != ' ')
 750                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 751         p++;
 752         if (*p == '0' && p[1] != ' ')
 753                 return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 754         if (date_overflows(parse_timestamp(p, &end, 10)))
 755                 return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 756         if ((end == p || *end != ' '))
 757                 return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 758         p = end + 1;
 759         if ((*p != '+' && *p != '-') ||
 760             !isdigit(p[1]) ||
 761             !isdigit(p[2]) ||
 762             !isdigit(p[3]) ||
 763             !isdigit(p[4]) ||
 764             (p[5] != '\n'))
 765                 return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 766         p += 6;
 767         return 0;
 768 }
 769
 770 static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 771         unsigned long size, struct fsck_options *options)
 772 {
 773         struct object_id tree_oid, oid;
 774         struct commit_graft *graft;
 775         unsigned parent_count, parent_line_count = 0, author_count;
 776         int err;
 777         const char *buffer_begin = buffer;
 778         const char *p;
 779
 780         if (verify_headers(buffer, size, &commit->object, options))
 781                 return -1;
 782
 783         if (!skip_prefix(buffer, "tree ", &buffer))
 784                 return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 785         if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
 786                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 787                 if (err)
 788                         return err;
 789         }
 790         buffer = p + 1;
 791         while (skip_prefix(buffer, "parent ", &buffer)) {
 792                 if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
 793                         err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 794                         if (err)
 795                                 return err;
 796                 }
 797                 buffer = p + 1;
 798                 parent_line_count++;
 799         }
 800         graft = lookup_commit_graft(the_repository, &commit->object.oid);
 801         parent_count = commit_list_count(commit->parents);
 802         if (graft) {
 803                 if (graft->nr_parent == -1 && !parent_count)
 804                         ; /* shallow commit */
 805                 else if (graft->nr_parent != parent_count) {
 806                         err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 807                         if (err)
 808                                 return err;
 809                 }
 810         } else {
 811                 if (parent_count != parent_line_count) {
 812                         err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 813                         if (err)
 814                                 return err;
 815                 }
 816         }
 817         author_count = 0;
 818         while (skip_prefix(buffer, "author ", &buffer)) {
 819                 author_count++;
 820                 err = fsck_ident(&buffer, &commit->object, options);
 821                 if (err)
 822                         return err;
 823         }
 824         if (author_count < 1)
 825                 err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 826         else if (author_count > 1)
 827                 err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 828         if (err)
 829                 return err;
 830         if (!skip_prefix(buffer, "committer ", &buffer))
 831                 return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 832         err = fsck_ident(&buffer, &commit->object, options);
 833         if (err)
 834                 return err;
 835         if (!get_commit_tree(commit)) {
 836                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", oid_to_hex(&tree_oid));
 837                 if (err)
 838                         return err;
 839         }
 840         if (memchr(buffer_begin, '\0', size)) {
 841                 err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
 842                              "NUL byte in the commit object body");
 843                 if (err)
 844                         return err;
 845         }
 846         return 0;
 847 }
 848
 849 static int fsck_commit(struct commit *commit, const char *data,
 850         unsigned long size, struct fsck_options *options)
 851 {
 852         const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 853         int ret = fsck_commit_buffer(commit, buffer, size, options);
 854         if (!data)
 855                 unuse_commit_buffer(commit, buffer);
 856         return ret;
 857 }
 858
 859 static int fsck_tag_buffer(struct tag *tag, const char *data,
 860         unsigned long size, struct fsck_options *options)
 861 {
 862         struct object_id oid;
 863         int ret = 0;
 864         const char *buffer;
 865         char *to_free = NULL, *eol;
 866         struct strbuf sb = STRBUF_INIT;
 867         const char *p;
 868
 869         if (data)
 870                 buffer = data;
 871         else {
 872                 enum object_type type;
 873
 874                 buffer = to_free =
 875                         read_object_file(&tag->object.oid, &type, &size);
 876                 if (!buffer)
 877                         return report(options, &tag->object,
 878                                 FSCK_MSG_MISSING_TAG_OBJECT,
 879                                 "cannot read tag object");
 880
 881                 if (type != OBJ_TAG) {
 882                         ret = report(options, &tag->object,
 883                                 FSCK_MSG_TAG_OBJECT_NOT_TAG,
 884                                 "expected tag got %s",
 885                             type_name(type));
 886                         goto done;
 887                 }
 888         }
 889
 890         ret = verify_headers(buffer, size, &tag->object, options);
 891         if (ret)
 892                 goto done;
 893
 894         if (!skip_prefix(buffer, "object ", &buffer)) {
 895                 ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 896                 goto done;
 897         }
 898         if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
 899                 ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 900                 if (ret)
 901                         goto done;
 902         }
 903         buffer = p + 1;
 904
 905         if (!skip_prefix(buffer, "type ", &buffer)) {
 906                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 907                 goto done;
 908         }
 909         eol = strchr(buffer, '\n');
 910         if (!eol) {
 911                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 912                 goto done;
 913         }
 914         if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 915                 ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 916         if (ret)
 917                 goto done;
 918         buffer = eol + 1;
 919
 920         if (!skip_prefix(buffer, "tag ", &buffer)) {
 921                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 922                 goto done;
 923         }
 924         eol = strchr(buffer, '\n');
 925         if (!eol) {
 926                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 927                 goto done;
 928         }
 929         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 930         if (check_refname_format(sb.buf, 0)) {
 931                 ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 932                            "invalid 'tag' name: %.*s",
 933                            (int)(eol - buffer), buffer);
 934                 if (ret)
 935                         goto done;
 936         }
 937         buffer = eol + 1;
 938
 939         if (!skip_prefix(buffer, "tagger ", &buffer)) {
 940                 /* early tags do not contain 'tagger' lines; warn only */
 941                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 942                 if (ret)
 943                         goto done;
 944         }
 945         else
 946                 ret = fsck_ident(&buffer, &tag->object, options);
 947
 948 done:
 949         strbuf_release(&sb);
 950         free(to_free);
 951         return ret;
 952 }
 953
 954 static int fsck_tag(struct tag *tag, const char *data,
 955         unsigned long size, struct fsck_options *options)
 956 {
 957         struct object *tagged = tag->tagged;
 958
 959         if (!tagged)
 960                 return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 961
 962         return fsck_tag_buffer(tag, data, size, options);
 963 }
 964
 965 struct fsck_gitmodules_data {
 966         struct object *obj;
 967         struct fsck_options *options;
 968         int ret;
 969 };
 970
 971 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
 972 {
 973         struct fsck_gitmodules_data *data = vdata;
 974         const char *subsection, *key;
 975         int subsection_len;
 976         char *name;
 977
 978         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
 979             !subsection)
 980                 return 0;
 981
 982         name = xmemdupz(subsection, subsection_len);
 983         if (check_submodule_name(name) < 0)
 984                 data->ret |= report(data->options, data->obj,
 985                                     FSCK_MSG_GITMODULES_NAME,
 986                                     "disallowed submodule name: %s",
 987                                     name);
 988         free(name);
 989
 990         return 0;
 991 }
 992
 993 static int fsck_blob(struct blob *blob, const char *buf,
 994                      unsigned long size, struct fsck_options *options)
 995 {
 996         struct fsck_gitmodules_data data;
 997
 998         if (!oidset_contains(&gitmodules_found, &blob->object.oid))
 999                 return 0;
1000         oidset_insert(&gitmodules_done, &blob->object.oid);
1001
1002         if (!buf) {
1003                 /*
1004                  * A missing buffer here is a sign that the caller found the
1005                  * blob too gigantic to load into memory. Let's just consider
1006                  * that an error.
1007                  */
1008                 return report(options, &blob->object,
1009                               FSCK_MSG_GITMODULES_PARSE,
1010                               ".gitmodules too large to parse");
1011         }
1012
1013         data.obj = &blob->object;
1014         data.options = options;
1015         data.ret = 0;
1016         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1017                                 ".gitmodules", buf, size, &data))
1018                 data.ret |= report(options, &blob->object,
1019                                    FSCK_MSG_GITMODULES_PARSE,
1020                                    "could not parse gitmodules blob");
1021
1022         return data.ret;
1023 }
1024
1025 int fsck_object(struct object *obj, void *data, unsigned long size,
1026         struct fsck_options *options)
1027 {
1028         if (!obj)
1029                 return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1030
1031         if (obj->type == OBJ_BLOB)
1032                 return fsck_blob((struct blob *)obj, data, size, options);
1033         if (obj->type == OBJ_TREE)
1034                 return fsck_tree((struct tree *) obj, options);
1035         if (obj->type == OBJ_COMMIT)
1036                 return fsck_commit((struct commit *) obj, (const char *) data,
1037                         size, options);
1038         if (obj->type == OBJ_TAG)
1039                 return fsck_tag((struct tag *) obj, (const char *) data,
1040                         size, options);
1041
1042         return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
1043                           obj->type);
1044 }
1045
1046 int fsck_error_function(struct fsck_options *o,
1047         struct object *obj, int msg_type, const char *message)
1048 {
1049         if (msg_type == FSCK_WARN) {
1050                 warning("object %s: %s", describe_object(o, obj), message);
1051                 return 0;
1052         }
1053         error("object %s: %s", describe_object(o, obj), message);
1054         return 1;
1055 }
1056
1057 int fsck_finish(struct fsck_options *options)
1058 {
1059         int ret = 0;
1060         struct oidset_iter iter;
1061         const struct object_id *oid;
1062
1063         oidset_iter_init(&gitmodules_found, &iter);
1064         while ((oid = oidset_iter_next(&iter))) {
1065                 struct blob *blob;
1066                 enum object_type type;
1067                 unsigned long size;
1068                 char *buf;
1069
1070                 if (oidset_contains(&gitmodules_done, oid))
1071                         continue;
1072
1073                 blob = lookup_blob(oid);
1074                 if (!blob) {
1075                         struct object *obj = lookup_unknown_object(oid->hash);
1076                         ret |= report(options, obj,
1077                                       FSCK_MSG_GITMODULES_BLOB,
1078                                       "non-blob found at .gitmodules");
1079                         continue;
1080                 }
1081
1082                 buf = read_object_file(oid, &type, &size);
1083                 if (!buf) {
1084                         if (is_promisor_object(&blob->object.oid))
1085                                 continue;
1086                         ret |= report(options, &blob->object,
1087                                       FSCK_MSG_GITMODULES_MISSING,
1088                                       "unable to read .gitmodules blob");
1089                         continue;
1090                 }
1091
1092                 if (type == OBJ_BLOB)
1093                         ret |= fsck_blob(blob, buf, size, options);
1094                 else
1095                         ret |= report(options, &blob->object,
1096                                       FSCK_MSG_GITMODULES_BLOB,
1097                                       "non-blob found at .gitmodules");
1098                 free(buf);
1099         }
1100
1101
1102         oidset_clear(&gitmodules_found);
1103         oidset_clear(&gitmodules_done);
1104         return ret;
1105 }