fsck.c

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