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