git.oblomov.eu Git - git/blob - 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         FUNC(GITMODULES_URL, ERROR) \
  70         FUNC(GITMODULES_PATH, ERROR) \
  71         /* warnings */ \
  72         FUNC(BAD_FILEMODE, WARN) \
  73         FUNC(EMPTY_NAME, WARN) \
  74         FUNC(FULL_PATHNAME, WARN) \
  75         FUNC(HAS_DOT, WARN) \
  76         FUNC(HAS_DOTDOT, WARN) \
  77         FUNC(HAS_DOTGIT, WARN) \
  78         FUNC(NULL_SHA1, WARN) \
  79         FUNC(ZERO_PADDED_FILEMODE, WARN) \
  80         FUNC(NUL_IN_COMMIT, WARN) \
  81         /* infos (reported as warnings, but ignored by default) */ \
  82         FUNC(GITMODULES_PARSE, INFO) \
  83         FUNC(BAD_TAG_NAME, INFO) \
  84         FUNC(MISSING_TAGGER_ENTRY, INFO)
  85
  86 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
  87 enum fsck_msg_id {
  88         FOREACH_MSG_ID(MSG_ID)
  89         FSCK_MSG_MAX
  90 };
  91 #undef MSG_ID
  92
  93 #define STR(x) #x
  94 #define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
  95 static struct {
  96         const char *id_string;
  97         const char *downcased;
  98         const char *camelcased;
  99         int msg_type;
 100 } msg_id_info[FSCK_MSG_MAX + 1] = {
 101         FOREACH_MSG_ID(MSG_ID)
 102         { NULL, NULL, NULL, -1 }
 103 };
 104 #undef MSG_ID
 105
 106 static void prepare_msg_ids(void)
 107 {
 108         int i;
 109
 110         if (msg_id_info[0].downcased)
 111                 return;
 112
 113         /* convert id_string to lower case, without underscores. */
 114         for (i = 0; i < FSCK_MSG_MAX; i++) {
 115                 const char *p = msg_id_info[i].id_string;
 116                 int len = strlen(p);
 117                 char *q = xmalloc(len);
 118
 119                 msg_id_info[i].downcased = q;
 120                 while (*p)
 121                         if (*p == '_')
 122                                 p++;
 123                         else
 124                                 *(q)++ = tolower(*(p)++);
 125                 *q = '\0';
 126
 127                 p = msg_id_info[i].id_string;
 128                 q = xmalloc(len);
 129                 msg_id_info[i].camelcased = q;
 130                 while (*p) {
 131                         if (*p == '_') {
 132                                 p++;
 133                                 if (*p)
 134                                         *q++ = *p++;
 135                         } else {
 136                                 *q++ = tolower(*p++);
 137                         }
 138                 }
 139                 *q = '\0';
 140         }
 141 }
 142
 143 static int parse_msg_id(const char *text)
 144 {
 145         int i;
 146
 147         prepare_msg_ids();
 148
 149         for (i = 0; i < FSCK_MSG_MAX; i++)
 150                 if (!strcmp(text, msg_id_info[i].downcased))
 151                         return i;
 152
 153         return -1;
 154 }
 155
 156 void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
 157 {
 158         int i;
 159
 160         prepare_msg_ids();
 161
 162         for (i = 0; i < FSCK_MSG_MAX; i++)
 163                 list_config_item(list, prefix, msg_id_info[i].camelcased);
 164 }
 165
 166 static int fsck_msg_type(enum fsck_msg_id msg_id,
 167         struct fsck_options *options)
 168 {
 169         int msg_type;
 170
 171         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 172
 173         if (options->msg_type)
 174                 msg_type = options->msg_type[msg_id];
 175         else {
 176                 msg_type = msg_id_info[msg_id].msg_type;
 177                 if (options->strict && msg_type == FSCK_WARN)
 178                         msg_type = FSCK_ERROR;
 179         }
 180
 181         return msg_type;
 182 }
 183
 184 static void init_skiplist(struct fsck_options *options, const char *path)
 185 {
 186         FILE *fp;
 187         struct strbuf sb = STRBUF_INIT;
 188         struct object_id oid;
 189
 190         fp = fopen(path, "r");
 191         if (!fp)
 192                 die("Could not open skip list: %s", path);
 193         while (!strbuf_getline(&sb, fp)) {
 194                 const char *p;
 195                 const char *hash;
 196
 197                 /*
 198                  * Allow trailing comments, leading whitespace
 199                  * (including before commits), and empty or whitespace
 200                  * only lines.
 201                  */
 202                 hash = strchr(sb.buf, '#');
 203                 if (hash)
 204                         strbuf_setlen(&sb, hash - sb.buf);
 205                 strbuf_trim(&sb);
 206                 if (!sb.len)
 207                         continue;
 208
 209                 if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0')
 210                         die("Invalid SHA-1: %s", sb.buf);
 211                 oidset_insert(&options->skiplist, &oid);
 212         }
 213         if (ferror(fp))
 214                 die_errno("Could not read '%s'", path);
 215         fclose(fp);
 216         strbuf_release(&sb);
 217 }
 218
 219 static int parse_msg_type(const char *str)
 220 {
 221         if (!strcmp(str, "error"))
 222                 return FSCK_ERROR;
 223         else if (!strcmp(str, "warn"))
 224                 return FSCK_WARN;
 225         else if (!strcmp(str, "ignore"))
 226                 return FSCK_IGNORE;
 227         else
 228                 die("Unknown fsck message type: '%s'", str);
 229 }
 230
 231 int is_valid_msg_type(const char *msg_id, const char *msg_type)
 232 {
 233         if (parse_msg_id(msg_id) < 0)
 234                 return 0;
 235         parse_msg_type(msg_type);
 236         return 1;
 237 }
 238
 239 void fsck_set_msg_type(struct fsck_options *options,
 240                 const char *msg_id, const char *msg_type)
 241 {
 242         int id = parse_msg_id(msg_id), type;
 243
 244         if (id < 0)
 245                 die("Unhandled message id: %s", msg_id);
 246         type = parse_msg_type(msg_type);
 247
 248         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
 249                 die("Cannot demote %s to %s", msg_id, msg_type);
 250
 251         if (!options->msg_type) {
 252                 int i;
 253                 int *msg_type;
 254                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
 255                 for (i = 0; i < FSCK_MSG_MAX; i++)
 256                         msg_type[i] = fsck_msg_type(i, options);
 257                 options->msg_type = msg_type;
 258         }
 259
 260         options->msg_type[id] = type;
 261 }
 262
 263 void fsck_set_msg_types(struct fsck_options *options, const char *values)
 264 {
 265         char *buf = xstrdup(values), *to_free = buf;
 266         int done = 0;
 267
 268         while (!done) {
 269                 int len = strcspn(buf, " ,|"), equal;
 270
 271                 done = !buf[len];
 272                 if (!len) {
 273                         buf++;
 274                         continue;
 275                 }
 276                 buf[len] = '\0';
 277
 278                 for (equal = 0;
 279                      equal < len && buf[equal] != '=' && buf[equal] != ':';
 280                      equal++)
 281                         buf[equal] = tolower(buf[equal]);
 282                 buf[equal] = '\0';
 283
 284                 if (!strcmp(buf, "skiplist")) {
 285                         if (equal == len)
 286                                 die("skiplist requires a path");
 287                         init_skiplist(options, buf + equal + 1);
 288                         buf += len + 1;
 289                         continue;
 290                 }
 291
 292                 if (equal == len)
 293                         die("Missing '=': '%s'", buf);
 294
 295                 fsck_set_msg_type(options, buf, buf + equal + 1);
 296                 buf += len + 1;
 297         }
 298         free(to_free);
 299 }
 300
 301 static void append_msg_id(struct strbuf *sb, const char *msg_id)
 302 {
 303         for (;;) {
 304                 char c = *(msg_id)++;
 305
 306                 if (!c)
 307                         break;
 308                 if (c != '_')
 309                         strbuf_addch(sb, tolower(c));
 310                 else {
 311                         assert(*msg_id);
 312                         strbuf_addch(sb, *(msg_id)++);
 313                 }
 314         }
 315
 316         strbuf_addstr(sb, ": ");
 317 }
 318
 319 static int object_on_skiplist(struct fsck_options *opts, struct object *obj)
 320 {
 321         return opts && obj && oidset_contains(&opts->skiplist, &obj->oid);
 322 }
 323
 324 __attribute__((format (printf, 4, 5)))
 325 static int report(struct fsck_options *options, struct object *object,
 326         enum fsck_msg_id id, const char *fmt, ...)
 327 {
 328         va_list ap;
 329         struct strbuf sb = STRBUF_INIT;
 330         int msg_type = fsck_msg_type(id, options), result;
 331
 332         if (msg_type == FSCK_IGNORE)
 333                 return 0;
 334
 335         if (object_on_skiplist(options, object))
 336                 return 0;
 337
 338         if (msg_type == FSCK_FATAL)
 339                 msg_type = FSCK_ERROR;
 340         else if (msg_type == FSCK_INFO)
 341                 msg_type = FSCK_WARN;
 342
 343         append_msg_id(&sb, msg_id_info[id].id_string);
 344
 345         va_start(ap, fmt);
 346         strbuf_vaddf(&sb, fmt, ap);
 347         result = options->error_func(options, object, msg_type, sb.buf);
 348         strbuf_release(&sb);
 349         va_end(ap);
 350
 351         return result;
 352 }
 353
 354 static char *get_object_name(struct fsck_options *options, struct object *obj)
 355 {
 356         if (!options->object_names)
 357                 return NULL;
 358         return lookup_decoration(options->object_names, obj);
 359 }
 360
 361 static void put_object_name(struct fsck_options *options, struct object *obj,
 362         const char *fmt, ...)
 363 {
 364         va_list ap;
 365         struct strbuf buf = STRBUF_INIT;
 366         char *existing;
 367
 368         if (!options->object_names)
 369                 return;
 370         existing = lookup_decoration(options->object_names, obj);
 371         if (existing)
 372                 return;
 373         va_start(ap, fmt);
 374         strbuf_vaddf(&buf, fmt, ap);
 375         add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
 376         va_end(ap);
 377 }
 378
 379 static const char *describe_object(struct fsck_options *o, struct object *obj)
 380 {
 381         static struct strbuf buf = STRBUF_INIT;
 382         char *name;
 383
 384         strbuf_reset(&buf);
 385         strbuf_addstr(&buf, oid_to_hex(&obj->oid));
 386         if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
 387                 strbuf_addf(&buf, " (%s)", name);
 388
 389         return buf.buf;
 390 }
 391
 392 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 393 {
 394         struct tree_desc desc;
 395         struct name_entry entry;
 396         int res = 0;
 397         const char *name;
 398
 399         if (parse_tree(tree))
 400                 return -1;
 401
 402         name = get_object_name(options, &tree->object);
 403         if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
 404                 return -1;
 405         while (tree_entry_gently(&desc, &entry)) {
 406                 struct object *obj;
 407                 int result;
 408
 409                 if (S_ISGITLINK(entry.mode))
 410                         continue;
 411
 412                 if (S_ISDIR(entry.mode)) {
 413                         obj = (struct object *)lookup_tree(the_repository, entry.oid);
 414                         if (name && obj)
 415                                 put_object_name(options, obj, "%s%s/", name,
 416                                         entry.path);
 417                         result = options->walk(obj, OBJ_TREE, data, options);
 418                 }
 419                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
 420                         obj = (struct object *)lookup_blob(the_repository, entry.oid);
 421                         if (name && obj)
 422                                 put_object_name(options, obj, "%s%s", name,
 423                                         entry.path);
 424                         result = options->walk(obj, OBJ_BLOB, data, options);
 425                 }
 426                 else {
 427                         result = error("in tree %s: entry %s has bad mode %.6o",
 428                                         describe_object(options, &tree->object), entry.path, entry.mode);
 429                 }
 430                 if (result < 0)
 431                         return result;
 432                 if (!res)
 433                         res = result;
 434         }
 435         return res;
 436 }
 437
 438 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 439 {
 440         int counter = 0, generation = 0, name_prefix_len = 0;
 441         struct commit_list *parents;
 442         int res;
 443         int result;
 444         const char *name;
 445
 446         if (parse_commit(commit))
 447                 return -1;
 448
 449         name = get_object_name(options, &commit->object);
 450         if (name)
 451                 put_object_name(options, &get_commit_tree(commit)->object,
 452                                 "%s:", name);
 453
 454         result = options->walk((struct object *)get_commit_tree(commit),
 455                                OBJ_TREE, data, options);
 456         if (result < 0)
 457                 return result;
 458         res = result;
 459
 460         parents = commit->parents;
 461         if (name && parents) {
 462                 int len = strlen(name), power;
 463
 464                 if (len && name[len - 1] == '^') {
 465                         generation = 1;
 466                         name_prefix_len = len - 1;
 467                 }
 468                 else { /* parse ~<generation> suffix */
 469                         for (generation = 0, power = 1;
 470                              len && isdigit(name[len - 1]);
 471                              power *= 10)
 472                                 generation += power * (name[--len] - '0');
 473                         if (power > 1 && len && name[len - 1] == '~')
 474                                 name_prefix_len = len - 1;
 475                 }
 476         }
 477
 478         while (parents) {
 479                 if (name) {
 480                         struct object *obj = &parents->item->object;
 481
 482                         if (counter++)
 483                                 put_object_name(options, obj, "%s^%d",
 484                                         name, counter);
 485                         else if (generation > 0)
 486                                 put_object_name(options, obj, "%.*s~%d",
 487                                         name_prefix_len, name, generation + 1);
 488                         else
 489                                 put_object_name(options, obj, "%s^", name);
 490                 }
 491                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 492                 if (result < 0)
 493                         return result;
 494                 if (!res)
 495                         res = result;
 496                 parents = parents->next;
 497         }
 498         return res;
 499 }
 500
 501 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 502 {
 503         char *name = get_object_name(options, &tag->object);
 504
 505         if (parse_tag(tag))
 506                 return -1;
 507         if (name)
 508                 put_object_name(options, tag->tagged, "%s", name);
 509         return options->walk(tag->tagged, OBJ_ANY, data, options);
 510 }
 511
 512 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 513 {
 514         if (!obj)
 515                 return -1;
 516
 517         if (obj->type == OBJ_NONE)
 518                 parse_object(the_repository, &obj->oid);
 519
 520         switch (obj->type) {
 521         case OBJ_BLOB:
 522                 return 0;
 523         case OBJ_TREE:
 524                 return fsck_walk_tree((struct tree *)obj, data, options);
 525         case OBJ_COMMIT:
 526                 return fsck_walk_commit((struct commit *)obj, data, options);
 527         case OBJ_TAG:
 528                 return fsck_walk_tag((struct tag *)obj, data, options);
 529         default:
 530                 error("Unknown object type for %s", describe_object(options, obj));
 531                 return -1;
 532         }
 533 }
 534
 535 /*
 536  * The entries in a tree are ordered in the _path_ order,
 537  * which means that a directory entry is ordered by adding
 538  * a slash to the end of it.
 539  *
 540  * So a directory called "a" is ordered _after_ a file
 541  * called "a.c", because "a/" sorts after "a.c".
 542  */
 543 #define TREE_UNORDERED (-1)
 544 #define TREE_HAS_DUPS  (-2)
 545
 546 static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 547 {
 548         int len1 = strlen(name1);
 549         int len2 = strlen(name2);
 550         int len = len1 < len2 ? len1 : len2;
 551         unsigned char c1, c2;
 552         int cmp;
 553
 554         cmp = memcmp(name1, name2, len);
 555         if (cmp < 0)
 556                 return 0;
 557         if (cmp > 0)
 558                 return TREE_UNORDERED;
 559
 560         /*
 561          * Ok, the first <len> characters are the same.
 562          * Now we need to order the next one, but turn
 563          * a '\0' into a '/' for a directory entry.
 564          */
 565         c1 = name1[len];
 566         c2 = name2[len];
 567         if (!c1 && !c2)
 568                 /*
 569                  * git-write-tree used to write out a nonsense tree that has
 570                  * entries with the same name, one blob and one tree.  Make
 571                  * sure we do not have duplicate entries.
 572                  */
 573                 return TREE_HAS_DUPS;
 574         if (!c1 && S_ISDIR(mode1))
 575                 c1 = '/';
 576         if (!c2 && S_ISDIR(mode2))
 577                 c2 = '/';
 578         return c1 < c2 ? 0 : TREE_UNORDERED;
 579 }
 580
 581 static int fsck_tree(struct tree *item, struct fsck_options *options)
 582 {
 583         int retval = 0;
 584         int has_null_sha1 = 0;
 585         int has_full_path = 0;
 586         int has_empty_name = 0;
 587         int has_dot = 0;
 588         int has_dotdot = 0;
 589         int has_dotgit = 0;
 590         int has_zero_pad = 0;
 591         int has_bad_modes = 0;
 592         int has_dup_entries = 0;
 593         int not_properly_sorted = 0;
 594         struct tree_desc desc;
 595         unsigned o_mode;
 596         const char *o_name;
 597
 598         if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
 599                 retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 600                 return retval;
 601         }
 602
 603         o_mode = 0;
 604         o_name = NULL;
 605
 606         while (desc.size) {
 607                 unsigned mode;
 608                 const char *name;
 609                 const struct object_id *oid;
 610
 611                 oid = tree_entry_extract(&desc, &name, &mode);
 612
 613                 has_null_sha1 |= is_null_oid(oid);
 614                 has_full_path |= !!strchr(name, '/');
 615                 has_empty_name |= !*name;
 616                 has_dot |= !strcmp(name, ".");
 617                 has_dotdot |= !strcmp(name, "..");
 618                 has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
 619                 has_zero_pad |= *(char *)desc.buffer == '0';
 620
 621                 if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
 622                         if (!S_ISLNK(mode))
 623                                 oidset_insert(&gitmodules_found, oid);
 624                         else
 625                                 retval += report(options, &item->object,
 626                                                  FSCK_MSG_GITMODULES_SYMLINK,
 627                                                  ".gitmodules is a symbolic link");
 628                 }
 629
 630                 if (update_tree_entry_gently(&desc)) {
 631                         retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 632                         break;
 633                 }
 634
 635                 switch (mode) {
 636                 /*
 637                  * Standard modes..
 638                  */
 639                 case S_IFREG | 0755:
 640                 case S_IFREG | 0644:
 641                 case S_IFLNK:
 642                 case S_IFDIR:
 643                 case S_IFGITLINK:
 644                         break;
 645                 /*
 646                  * This is nonstandard, but we had a few of these
 647                  * early on when we honored the full set of mode
 648                  * bits..
 649                  */
 650                 case S_IFREG | 0664:
 651                         if (!options->strict)
 652                                 break;
 653                         /* fallthrough */
 654                 default:
 655                         has_bad_modes = 1;
 656                 }
 657
 658                 if (o_name) {
 659                         switch (verify_ordered(o_mode, o_name, mode, name)) {
 660                         case TREE_UNORDERED:
 661                                 not_properly_sorted = 1;
 662                                 break;
 663                         case TREE_HAS_DUPS:
 664                                 has_dup_entries = 1;
 665                                 break;
 666                         default:
 667                                 break;
 668                         }
 669                 }
 670
 671                 o_mode = mode;
 672                 o_name = name;
 673         }
 674
 675         if (has_null_sha1)
 676                 retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 677         if (has_full_path)
 678                 retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 679         if (has_empty_name)
 680                 retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 681         if (has_dot)
 682                 retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 683         if (has_dotdot)
 684                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 685         if (has_dotgit)
 686                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 687         if (has_zero_pad)
 688                 retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 689         if (has_bad_modes)
 690                 retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 691         if (has_dup_entries)
 692                 retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 693         if (not_properly_sorted)
 694                 retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 695         return retval;
 696 }
 697
 698 static int verify_headers(const void *data, unsigned long size,
 699                           struct object *obj, struct fsck_options *options)
 700 {
 701         const char *buffer = (const char *)data;
 702         unsigned long i;
 703
 704         for (i = 0; i < size; i++) {
 705                 switch (buffer[i]) {
 706                 case '\0':
 707                         return report(options, obj,
 708                                 FSCK_MSG_NUL_IN_HEADER,
 709                                 "unterminated header: NUL at offset %ld", i);
 710                 case '\n':
 711                         if (i + 1 < size && buffer[i + 1] == '\n')
 712                                 return 0;
 713                 }
 714         }
 715
 716         /*
 717          * We did not find double-LF that separates the header
 718          * and the body.  Not having a body is not a crime but
 719          * we do want to see the terminating LF for the last header
 720          * line.
 721          */
 722         if (size && buffer[size - 1] == '\n')
 723                 return 0;
 724
 725         return report(options, obj,
 726                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 727 }
 728
 729 static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 730 {
 731         const char *p = *ident;
 732         char *end;
 733
 734         *ident = strchrnul(*ident, '\n');
 735         if (**ident == '\n')
 736                 (*ident)++;
 737
 738         if (*p == '<')
 739                 return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 740         p += strcspn(p, "<>\n");
 741         if (*p == '>')
 742                 return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 743         if (*p != '<')
 744                 return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 745         if (p[-1] != ' ')
 746                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 747         p++;
 748         p += strcspn(p, "<>\n");
 749         if (*p != '>')
 750                 return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 751         p++;
 752         if (*p != ' ')
 753                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 754         p++;
 755         if (*p == '0' && p[1] != ' ')
 756                 return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 757         if (date_overflows(parse_timestamp(p, &end, 10)))
 758                 return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 759         if ((end == p || *end != ' '))
 760                 return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 761         p = end + 1;
 762         if ((*p != '+' && *p != '-') ||
 763             !isdigit(p[1]) ||
 764             !isdigit(p[2]) ||
 765             !isdigit(p[3]) ||
 766             !isdigit(p[4]) ||
 767             (p[5] != '\n'))
 768                 return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 769         p += 6;
 770         return 0;
 771 }
 772
 773 static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 774         unsigned long size, struct fsck_options *options)
 775 {
 776         struct object_id tree_oid, oid;
 777         struct commit_graft *graft;
 778         unsigned parent_count, parent_line_count = 0, author_count;
 779         int err;
 780         const char *buffer_begin = buffer;
 781         const char *p;
 782
 783         if (verify_headers(buffer, size, &commit->object, options))
 784                 return -1;
 785
 786         if (!skip_prefix(buffer, "tree ", &buffer))
 787                 return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 788         if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
 789                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 790                 if (err)
 791                         return err;
 792         }
 793         buffer = p + 1;
 794         while (skip_prefix(buffer, "parent ", &buffer)) {
 795                 if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
 796                         err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 797                         if (err)
 798                                 return err;
 799                 }
 800                 buffer = p + 1;
 801                 parent_line_count++;
 802         }
 803         graft = lookup_commit_graft(the_repository, &commit->object.oid);
 804         parent_count = commit_list_count(commit->parents);
 805         if (graft) {
 806                 if (graft->nr_parent == -1 && !parent_count)
 807                         ; /* shallow commit */
 808                 else if (graft->nr_parent != parent_count) {
 809                         err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 810                         if (err)
 811                                 return err;
 812                 }
 813         } else {
 814                 if (parent_count != parent_line_count) {
 815                         err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 816                         if (err)
 817                                 return err;
 818                 }
 819         }
 820         author_count = 0;
 821         while (skip_prefix(buffer, "author ", &buffer)) {
 822                 author_count++;
 823                 err = fsck_ident(&buffer, &commit->object, options);
 824                 if (err)
 825                         return err;
 826         }
 827         if (author_count < 1)
 828                 err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 829         else if (author_count > 1)
 830                 err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 831         if (err)
 832                 return err;
 833         if (!skip_prefix(buffer, "committer ", &buffer))
 834                 return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 835         err = fsck_ident(&buffer, &commit->object, options);
 836         if (err)
 837                 return err;
 838         if (!get_commit_tree(commit)) {
 839                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", oid_to_hex(&tree_oid));
 840                 if (err)
 841                         return err;
 842         }
 843         if (memchr(buffer_begin, '\0', size)) {
 844                 err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
 845                              "NUL byte in the commit object body");
 846                 if (err)
 847                         return err;
 848         }
 849         return 0;
 850 }
 851
 852 static int fsck_commit(struct commit *commit, const char *data,
 853         unsigned long size, struct fsck_options *options)
 854 {
 855         const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 856         int ret = fsck_commit_buffer(commit, buffer, size, options);
 857         if (!data)
 858                 unuse_commit_buffer(commit, buffer);
 859         return ret;
 860 }
 861
 862 static int fsck_tag_buffer(struct tag *tag, const char *data,
 863         unsigned long size, struct fsck_options *options)
 864 {
 865         struct object_id oid;
 866         int ret = 0;
 867         const char *buffer;
 868         char *to_free = NULL, *eol;
 869         struct strbuf sb = STRBUF_INIT;
 870         const char *p;
 871
 872         if (data)
 873                 buffer = data;
 874         else {
 875                 enum object_type type;
 876
 877                 buffer = to_free =
 878                         read_object_file(&tag->object.oid, &type, &size);
 879                 if (!buffer)
 880                         return report(options, &tag->object,
 881                                 FSCK_MSG_MISSING_TAG_OBJECT,
 882                                 "cannot read tag object");
 883
 884                 if (type != OBJ_TAG) {
 885                         ret = report(options, &tag->object,
 886                                 FSCK_MSG_TAG_OBJECT_NOT_TAG,
 887                                 "expected tag got %s",
 888                             type_name(type));
 889                         goto done;
 890                 }
 891         }
 892
 893         ret = verify_headers(buffer, size, &tag->object, options);
 894         if (ret)
 895                 goto done;
 896
 897         if (!skip_prefix(buffer, "object ", &buffer)) {
 898                 ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 899                 goto done;
 900         }
 901         if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
 902                 ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 903                 if (ret)
 904                         goto done;
 905         }
 906         buffer = p + 1;
 907
 908         if (!skip_prefix(buffer, "type ", &buffer)) {
 909                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 910                 goto done;
 911         }
 912         eol = strchr(buffer, '\n');
 913         if (!eol) {
 914                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 915                 goto done;
 916         }
 917         if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 918                 ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 919         if (ret)
 920                 goto done;
 921         buffer = eol + 1;
 922
 923         if (!skip_prefix(buffer, "tag ", &buffer)) {
 924                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 925                 goto done;
 926         }
 927         eol = strchr(buffer, '\n');
 928         if (!eol) {
 929                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 930                 goto done;
 931         }
 932         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 933         if (check_refname_format(sb.buf, 0)) {
 934                 ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 935                            "invalid 'tag' name: %.*s",
 936                            (int)(eol - buffer), buffer);
 937                 if (ret)
 938                         goto done;
 939         }
 940         buffer = eol + 1;
 941
 942         if (!skip_prefix(buffer, "tagger ", &buffer)) {
 943                 /* early tags do not contain 'tagger' lines; warn only */
 944                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 945                 if (ret)
 946                         goto done;
 947         }
 948         else
 949                 ret = fsck_ident(&buffer, &tag->object, options);
 950
 951 done:
 952         strbuf_release(&sb);
 953         free(to_free);
 954         return ret;
 955 }
 956
 957 static int fsck_tag(struct tag *tag, const char *data,
 958         unsigned long size, struct fsck_options *options)
 959 {
 960         struct object *tagged = tag->tagged;
 961
 962         if (!tagged)
 963                 return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 964
 965         return fsck_tag_buffer(tag, data, size, options);
 966 }
 967
 968 struct fsck_gitmodules_data {
 969         struct object *obj;
 970         struct fsck_options *options;
 971         int ret;
 972 };
 973
 974 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
 975 {
 976         struct fsck_gitmodules_data *data = vdata;
 977         const char *subsection, *key;
 978         int subsection_len;
 979         char *name;
 980
 981         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
 982             !subsection)
 983                 return 0;
 984
 985         name = xmemdupz(subsection, subsection_len);
 986         if (check_submodule_name(name) < 0)
 987                 data->ret |= report(data->options, data->obj,
 988                                     FSCK_MSG_GITMODULES_NAME,
 989                                     "disallowed submodule name: %s",
 990                                     name);
 991         if (!strcmp(key, "url") && value &&
 992             looks_like_command_line_option(value))
 993                 data->ret |= report(data->options, data->obj,
 994                                     FSCK_MSG_GITMODULES_URL,
 995                                     "disallowed submodule url: %s",
 996                                     value);
 997         if (!strcmp(key, "path") && value &&
 998             looks_like_command_line_option(value))
 999                 data->ret |= report(data->options, data->obj,
1000                                     FSCK_MSG_GITMODULES_PATH,
1001                                     "disallowed submodule path: %s",
1002                                     value);
1003         free(name);
1004
1005         return 0;
1006 }
1007
1008 static int fsck_blob(struct blob *blob, const char *buf,
1009                      unsigned long size, struct fsck_options *options)
1010 {
1011         struct fsck_gitmodules_data data;
1012         struct config_options config_opts = { 0 };
1013
1014         if (!oidset_contains(&gitmodules_found, &blob->object.oid))
1015                 return 0;
1016         oidset_insert(&gitmodules_done, &blob->object.oid);
1017
1018         if (object_on_skiplist(options, &blob->object))
1019                 return 0;
1020
1021         if (!buf) {
1022                 /*
1023                  * A missing buffer here is a sign that the caller found the
1024                  * blob too gigantic to load into memory. Let's just consider
1025                  * that an error.
1026                  */
1027                 return report(options, &blob->object,
1028                               FSCK_MSG_GITMODULES_LARGE,
1029                               ".gitmodules too large to parse");
1030         }
1031
1032         data.obj = &blob->object;
1033         data.options = options;
1034         data.ret = 0;
1035         config_opts.error_action = CONFIG_ERROR_SILENT;
1036         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1037                                 ".gitmodules", buf, size, &data, &config_opts))
1038                 data.ret |= report(options, &blob->object,
1039                                    FSCK_MSG_GITMODULES_PARSE,
1040                                    "could not parse gitmodules blob");
1041
1042         return data.ret;
1043 }
1044
1045 int fsck_object(struct object *obj, void *data, unsigned long size,
1046         struct fsck_options *options)
1047 {
1048         if (!obj)
1049                 return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1050
1051         if (obj->type == OBJ_BLOB)
1052                 return fsck_blob((struct blob *)obj, data, size, options);
1053         if (obj->type == OBJ_TREE)
1054                 return fsck_tree((struct tree *) obj, options);
1055         if (obj->type == OBJ_COMMIT)
1056                 return fsck_commit((struct commit *) obj, (const char *) data,
1057                         size, options);
1058         if (obj->type == OBJ_TAG)
1059                 return fsck_tag((struct tag *) obj, (const char *) data,
1060                         size, options);
1061
1062         return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
1063                           obj->type);
1064 }
1065
1066 int fsck_error_function(struct fsck_options *o,
1067         struct object *obj, int msg_type, const char *message)
1068 {
1069         if (msg_type == FSCK_WARN) {
1070                 warning("object %s: %s", describe_object(o, obj), message);
1071                 return 0;
1072         }
1073         error("object %s: %s", describe_object(o, obj), message);
1074         return 1;
1075 }
1076
1077 int fsck_finish(struct fsck_options *options)
1078 {
1079         int ret = 0;
1080         struct oidset_iter iter;
1081         const struct object_id *oid;
1082
1083         oidset_iter_init(&gitmodules_found, &iter);
1084         while ((oid = oidset_iter_next(&iter))) {
1085                 struct blob *blob;
1086                 enum object_type type;
1087                 unsigned long size;
1088                 char *buf;
1089
1090                 if (oidset_contains(&gitmodules_done, oid))
1091                         continue;
1092
1093                 blob = lookup_blob(the_repository, oid);
1094                 if (!blob) {
1095                         struct object *obj = lookup_unknown_object(oid->hash);
1096                         ret |= report(options, obj,
1097                                       FSCK_MSG_GITMODULES_BLOB,
1098                                       "non-blob found at .gitmodules");
1099                         continue;
1100                 }
1101
1102                 buf = read_object_file(oid, &type, &size);
1103                 if (!buf) {
1104                         if (is_promisor_object(&blob->object.oid))
1105                                 continue;
1106                         ret |= report(options, &blob->object,
1107                                       FSCK_MSG_GITMODULES_MISSING,
1108                                       "unable to read .gitmodules blob");
1109                         continue;
1110                 }
1111
1112                 if (type == OBJ_BLOB)
1113                         ret |= fsck_blob(blob, buf, size, options);
1114                 else
1115                         ret |= report(options, &blob->object,
1116                                       FSCK_MSG_GITMODULES_BLOB,
1117                                       "non-blob found at .gitmodules");
1118                 free(buf);
1119         }
1120
1121
1122         oidset_clear(&gitmodules_found);
1123         oidset_clear(&gitmodules_done);
1124         return ret;
1125 }