Andrew's git / gitweb.git / fsck.c
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fsck.con commit Merge branch 'jk/safe-pipe-capture' into maint-2.10 (dca89d4)
   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
  14#define FSCK_FATAL -1
  15#define FSCK_INFO -2
  16
  17#define FOREACH_MSG_ID(FUNC) \
  18        /* fatal errors */ \
  19        FUNC(NUL_IN_HEADER, FATAL) \
  20        FUNC(UNTERMINATED_HEADER, FATAL) \
  21        /* errors */ \
  22        FUNC(BAD_DATE, ERROR) \
  23        FUNC(BAD_DATE_OVERFLOW, ERROR) \
  24        FUNC(BAD_EMAIL, ERROR) \
  25        FUNC(BAD_NAME, ERROR) \
  26        FUNC(BAD_OBJECT_SHA1, ERROR) \
  27        FUNC(BAD_PARENT_SHA1, ERROR) \
  28        FUNC(BAD_TAG_OBJECT, ERROR) \
  29        FUNC(BAD_TIMEZONE, ERROR) \
  30        FUNC(BAD_TREE, ERROR) \
  31        FUNC(BAD_TREE_SHA1, ERROR) \
  32        FUNC(BAD_TYPE, ERROR) \
  33        FUNC(DUPLICATE_ENTRIES, ERROR) \
  34        FUNC(MISSING_AUTHOR, ERROR) \
  35        FUNC(MISSING_COMMITTER, ERROR) \
  36        FUNC(MISSING_EMAIL, ERROR) \
  37        FUNC(MISSING_GRAFT, ERROR) \
  38        FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  39        FUNC(MISSING_OBJECT, ERROR) \
  40        FUNC(MISSING_PARENT, ERROR) \
  41        FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  42        FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  43        FUNC(MISSING_TAG, ERROR) \
  44        FUNC(MISSING_TAG_ENTRY, ERROR) \
  45        FUNC(MISSING_TAG_OBJECT, ERROR) \
  46        FUNC(MISSING_TREE, ERROR) \
  47        FUNC(MISSING_TYPE, ERROR) \
  48        FUNC(MISSING_TYPE_ENTRY, ERROR) \
  49        FUNC(MULTIPLE_AUTHORS, ERROR) \
  50        FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
  51        FUNC(TREE_NOT_SORTED, ERROR) \
  52        FUNC(UNKNOWN_TYPE, ERROR) \
  53        FUNC(ZERO_PADDED_DATE, ERROR) \
  54        /* warnings */ \
  55        FUNC(BAD_FILEMODE, WARN) \
  56        FUNC(EMPTY_NAME, WARN) \
  57        FUNC(FULL_PATHNAME, WARN) \
  58        FUNC(HAS_DOT, WARN) \
  59        FUNC(HAS_DOTDOT, WARN) \
  60        FUNC(HAS_DOTGIT, WARN) \
  61        FUNC(NULL_SHA1, WARN) \
  62        FUNC(ZERO_PADDED_FILEMODE, WARN) \
  63        FUNC(NUL_IN_COMMIT, WARN) \
  64        /* infos (reported as warnings, but ignored by default) */ \
  65        FUNC(BAD_TAG_NAME, INFO) \
  66        FUNC(MISSING_TAGGER_ENTRY, INFO)
  67
  68#define MSG_ID(id, msg_type) FSCK_MSG_##id,
  69enum fsck_msg_id {
  70        FOREACH_MSG_ID(MSG_ID)
  71        FSCK_MSG_MAX
  72};
  73#undef MSG_ID
  74
  75#define STR(x) #x
  76#define MSG_ID(id, msg_type) { STR(id), NULL, FSCK_##msg_type },
  77static struct {
  78        const char *id_string;
  79        const char *downcased;
  80        int msg_type;
  81} msg_id_info[FSCK_MSG_MAX + 1] = {
  82        FOREACH_MSG_ID(MSG_ID)
  83        { NULL, NULL, -1 }
  84};
  85#undef MSG_ID
  86
  87static int parse_msg_id(const char *text)
  88{
  89        int i;
  90
  91        if (!msg_id_info[0].downcased) {
  92                /* convert id_string to lower case, without underscores. */
  93                for (i = 0; i < FSCK_MSG_MAX; i++) {
  94                        const char *p = msg_id_info[i].id_string;
  95                        int len = strlen(p);
  96                        char *q = xmalloc(len);
  97
  98                        msg_id_info[i].downcased = q;
  99                        while (*p)
 100                                if (*p == '_')
 101                                        p++;
 102                                else
 103                                        *(q)++ = tolower(*(p)++);
 104                        *q = '\0';
 105                }
 106        }
 107
 108        for (i = 0; i < FSCK_MSG_MAX; i++)
 109                if (!strcmp(text, msg_id_info[i].downcased))
 110                        return i;
 111
 112        return -1;
 113}
 114
 115static int fsck_msg_type(enum fsck_msg_id msg_id,
 116        struct fsck_options *options)
 117{
 118        int msg_type;
 119
 120        assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 121
 122        if (options->msg_type)
 123                msg_type = options->msg_type[msg_id];
 124        else {
 125                msg_type = msg_id_info[msg_id].msg_type;
 126                if (options->strict && msg_type == FSCK_WARN)
 127                        msg_type = FSCK_ERROR;
 128        }
 129
 130        return msg_type;
 131}
 132
 133static void init_skiplist(struct fsck_options *options, const char *path)
 134{
 135        static struct sha1_array skiplist = SHA1_ARRAY_INIT;
 136        int sorted, fd;
 137        char buffer[41];
 138        unsigned char sha1[20];
 139
 140        if (options->skiplist)
 141                sorted = options->skiplist->sorted;
 142        else {
 143                sorted = 1;
 144                options->skiplist = &skiplist;
 145        }
 146
 147        fd = open(path, O_RDONLY);
 148        if (fd < 0)
 149                die("Could not open skip list: %s", path);
 150        for (;;) {
 151                int result = read_in_full(fd, buffer, sizeof(buffer));
 152                if (result < 0)
 153                        die_errno("Could not read '%s'", path);
 154                if (!result)
 155                        break;
 156                if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n')
 157                        die("Invalid SHA-1: %s", buffer);
 158                sha1_array_append(&skiplist, sha1);
 159                if (sorted && skiplist.nr > 1 &&
 160                                hashcmp(skiplist.sha1[skiplist.nr - 2],
 161                                        sha1) > 0)
 162                        sorted = 0;
 163        }
 164        close(fd);
 165
 166        if (sorted)
 167                skiplist.sorted = 1;
 168}
 169
 170static int parse_msg_type(const char *str)
 171{
 172        if (!strcmp(str, "error"))
 173                return FSCK_ERROR;
 174        else if (!strcmp(str, "warn"))
 175                return FSCK_WARN;
 176        else if (!strcmp(str, "ignore"))
 177                return FSCK_IGNORE;
 178        else
 179                die("Unknown fsck message type: '%s'", str);
 180}
 181
 182int is_valid_msg_type(const char *msg_id, const char *msg_type)
 183{
 184        if (parse_msg_id(msg_id) < 0)
 185                return 0;
 186        parse_msg_type(msg_type);
 187        return 1;
 188}
 189
 190void fsck_set_msg_type(struct fsck_options *options,
 191                const char *msg_id, const char *msg_type)
 192{
 193        int id = parse_msg_id(msg_id), type;
 194
 195        if (id < 0)
 196                die("Unhandled message id: %s", msg_id);
 197        type = parse_msg_type(msg_type);
 198
 199        if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
 200                die("Cannot demote %s to %s", msg_id, msg_type);
 201
 202        if (!options->msg_type) {
 203                int i;
 204                int *msg_type;
 205                ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
 206                for (i = 0; i < FSCK_MSG_MAX; i++)
 207                        msg_type[i] = fsck_msg_type(i, options);
 208                options->msg_type = msg_type;
 209        }
 210
 211        options->msg_type[id] = type;
 212}
 213
 214void fsck_set_msg_types(struct fsck_options *options, const char *values)
 215{
 216        char *buf = xstrdup(values), *to_free = buf;
 217        int done = 0;
 218
 219        while (!done) {
 220                int len = strcspn(buf, " ,|"), equal;
 221
 222                done = !buf[len];
 223                if (!len) {
 224                        buf++;
 225                        continue;
 226                }
 227                buf[len] = '\0';
 228
 229                for (equal = 0;
 230                     equal < len && buf[equal] != '=' && buf[equal] != ':';
 231                     equal++)
 232                        buf[equal] = tolower(buf[equal]);
 233                buf[equal] = '\0';
 234
 235                if (!strcmp(buf, "skiplist")) {
 236                        if (equal == len)
 237                                die("skiplist requires a path");
 238                        init_skiplist(options, buf + equal + 1);
 239                        buf += len + 1;
 240                        continue;
 241                }
 242
 243                if (equal == len)
 244                        die("Missing '=': '%s'", buf);
 245
 246                fsck_set_msg_type(options, buf, buf + equal + 1);
 247                buf += len + 1;
 248        }
 249        free(to_free);
 250}
 251
 252static void append_msg_id(struct strbuf *sb, const char *msg_id)
 253{
 254        for (;;) {
 255                char c = *(msg_id)++;
 256
 257                if (!c)
 258                        break;
 259                if (c != '_')
 260                        strbuf_addch(sb, tolower(c));
 261                else {
 262                        assert(*msg_id);
 263                        strbuf_addch(sb, *(msg_id)++);
 264                }
 265        }
 266
 267        strbuf_addstr(sb, ": ");
 268}
 269
 270__attribute__((format (printf, 4, 5)))
 271static int report(struct fsck_options *options, struct object *object,
 272        enum fsck_msg_id id, const char *fmt, ...)
 273{
 274        va_list ap;
 275        struct strbuf sb = STRBUF_INIT;
 276        int msg_type = fsck_msg_type(id, options), result;
 277
 278        if (msg_type == FSCK_IGNORE)
 279                return 0;
 280
 281        if (options->skiplist && object &&
 282                        sha1_array_lookup(options->skiplist, object->oid.hash) >= 0)
 283                return 0;
 284
 285        if (msg_type == FSCK_FATAL)
 286                msg_type = FSCK_ERROR;
 287        else if (msg_type == FSCK_INFO)
 288                msg_type = FSCK_WARN;
 289
 290        append_msg_id(&sb, msg_id_info[id].id_string);
 291
 292        va_start(ap, fmt);
 293        strbuf_vaddf(&sb, fmt, ap);
 294        result = options->error_func(options, object, msg_type, sb.buf);
 295        strbuf_release(&sb);
 296        va_end(ap);
 297
 298        return result;
 299}
 300
 301static char *get_object_name(struct fsck_options *options, struct object *obj)
 302{
 303        if (!options->object_names)
 304                return NULL;
 305        return lookup_decoration(options->object_names, obj);
 306}
 307
 308static void put_object_name(struct fsck_options *options, struct object *obj,
 309        const char *fmt, ...)
 310{
 311        va_list ap;
 312        struct strbuf buf = STRBUF_INIT;
 313        char *existing;
 314
 315        if (!options->object_names)
 316                return;
 317        existing = lookup_decoration(options->object_names, obj);
 318        if (existing)
 319                return;
 320        va_start(ap, fmt);
 321        strbuf_vaddf(&buf, fmt, ap);
 322        add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
 323        va_end(ap);
 324}
 325
 326static const char *describe_object(struct fsck_options *o, struct object *obj)
 327{
 328        static struct strbuf buf = STRBUF_INIT;
 329        char *name;
 330
 331        strbuf_reset(&buf);
 332        strbuf_addstr(&buf, oid_to_hex(&obj->oid));
 333        if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
 334                strbuf_addf(&buf, " (%s)", name);
 335
 336        return buf.buf;
 337}
 338
 339static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 340{
 341        struct tree_desc desc;
 342        struct name_entry entry;
 343        int res = 0;
 344        const char *name;
 345
 346        if (parse_tree(tree))
 347                return -1;
 348
 349        name = get_object_name(options, &tree->object);
 350        init_tree_desc(&desc, tree->buffer, tree->size);
 351        while (tree_entry(&desc, &entry)) {
 352                struct object *obj;
 353                int result;
 354
 355                if (S_ISGITLINK(entry.mode))
 356                        continue;
 357
 358                if (S_ISDIR(entry.mode)) {
 359                        obj = &lookup_tree(entry.oid->hash)->object;
 360                        if (name)
 361                                put_object_name(options, obj, "%s%s/", name,
 362                                        entry.path);
 363                        result = options->walk(obj, OBJ_TREE, data, options);
 364                }
 365                else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
 366                        obj = &lookup_blob(entry.oid->hash)->object;
 367                        if (name)
 368                                put_object_name(options, obj, "%s%s", name,
 369                                        entry.path);
 370                        result = options->walk(obj, OBJ_BLOB, data, options);
 371                }
 372                else {
 373                        result = error("in tree %s: entry %s has bad mode %.6o",
 374                                        describe_object(options, &tree->object), entry.path, entry.mode);
 375                }
 376                if (result < 0)
 377                        return result;
 378                if (!res)
 379                        res = result;
 380        }
 381        return res;
 382}
 383
 384static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 385{
 386        int counter = 0, generation = 0, name_prefix_len = 0;
 387        struct commit_list *parents;
 388        int res;
 389        int result;
 390        const char *name;
 391
 392        if (parse_commit(commit))
 393                return -1;
 394
 395        name = get_object_name(options, &commit->object);
 396        if (name)
 397                put_object_name(options, &commit->tree->object, "%s:", name);
 398
 399        result = options->walk((struct object *)commit->tree, OBJ_TREE, data, options);
 400        if (result < 0)
 401                return result;
 402        res = result;
 403
 404        parents = commit->parents;
 405        if (name && parents) {
 406                int len = strlen(name), power;
 407
 408                if (len && name[len - 1] == '^') {
 409                        generation = 1;
 410                        name_prefix_len = len - 1;
 411                }
 412                else { /* parse ~<generation> suffix */
 413                        for (generation = 0, power = 1;
 414                             len && isdigit(name[len - 1]);
 415                             power *= 10)
 416                                generation += power * (name[--len] - '0');
 417                        if (power > 1 && len && name[len - 1] == '~')
 418                                name_prefix_len = len - 1;
 419                }
 420        }
 421
 422        while (parents) {
 423                if (name) {
 424                        struct object *obj = &parents->item->object;
 425
 426                        if (++counter > 1)
 427                                put_object_name(options, obj, "%s^%d",
 428                                        name, counter);
 429                        else if (generation > 0)
 430                                put_object_name(options, obj, "%.*s~%d",
 431                                        name_prefix_len, name, generation + 1);
 432                        else
 433                                put_object_name(options, obj, "%s^", name);
 434                }
 435                result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 436                if (result < 0)
 437                        return result;
 438                if (!res)
 439                        res = result;
 440                parents = parents->next;
 441        }
 442        return res;
 443}
 444
 445static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 446{
 447        char *name = get_object_name(options, &tag->object);
 448
 449        if (parse_tag(tag))
 450                return -1;
 451        if (name)
 452                put_object_name(options, tag->tagged, "%s", name);
 453        return options->walk(tag->tagged, OBJ_ANY, data, options);
 454}
 455
 456int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 457{
 458        if (!obj)
 459                return -1;
 460        switch (obj->type) {
 461        case OBJ_BLOB:
 462                return 0;
 463        case OBJ_TREE:
 464                return fsck_walk_tree((struct tree *)obj, data, options);
 465        case OBJ_COMMIT:
 466                return fsck_walk_commit((struct commit *)obj, data, options);
 467        case OBJ_TAG:
 468                return fsck_walk_tag((struct tag *)obj, data, options);
 469        default:
 470                error("Unknown object type for %s", describe_object(options, obj));
 471                return -1;
 472        }
 473}
 474
 475/*
 476 * The entries in a tree are ordered in the _path_ order,
 477 * which means that a directory entry is ordered by adding
 478 * a slash to the end of it.
 479 *
 480 * So a directory called "a" is ordered _after_ a file
 481 * called "a.c", because "a/" sorts after "a.c".
 482 */
 483#define TREE_UNORDERED (-1)
 484#define TREE_HAS_DUPS  (-2)
 485
 486static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 487{
 488        int len1 = strlen(name1);
 489        int len2 = strlen(name2);
 490        int len = len1 < len2 ? len1 : len2;
 491        unsigned char c1, c2;
 492        int cmp;
 493
 494        cmp = memcmp(name1, name2, len);
 495        if (cmp < 0)
 496                return 0;
 497        if (cmp > 0)
 498                return TREE_UNORDERED;
 499
 500        /*
 501         * Ok, the first <len> characters are the same.
 502         * Now we need to order the next one, but turn
 503         * a '\0' into a '/' for a directory entry.
 504         */
 505        c1 = name1[len];
 506        c2 = name2[len];
 507        if (!c1 && !c2)
 508                /*
 509                 * git-write-tree used to write out a nonsense tree that has
 510                 * entries with the same name, one blob and one tree.  Make
 511                 * sure we do not have duplicate entries.
 512                 */
 513                return TREE_HAS_DUPS;
 514        if (!c1 && S_ISDIR(mode1))
 515                c1 = '/';
 516        if (!c2 && S_ISDIR(mode2))
 517                c2 = '/';
 518        return c1 < c2 ? 0 : TREE_UNORDERED;
 519}
 520
 521static int fsck_tree(struct tree *item, struct fsck_options *options)
 522{
 523        int retval;
 524        int has_null_sha1 = 0;
 525        int has_full_path = 0;
 526        int has_empty_name = 0;
 527        int has_dot = 0;
 528        int has_dotdot = 0;
 529        int has_dotgit = 0;
 530        int has_zero_pad = 0;
 531        int has_bad_modes = 0;
 532        int has_dup_entries = 0;
 533        int not_properly_sorted = 0;
 534        struct tree_desc desc;
 535        unsigned o_mode;
 536        const char *o_name;
 537
 538        init_tree_desc(&desc, item->buffer, item->size);
 539
 540        o_mode = 0;
 541        o_name = NULL;
 542
 543        while (desc.size) {
 544                unsigned mode;
 545                const char *name;
 546                const struct object_id *oid;
 547
 548                oid = tree_entry_extract(&desc, &name, &mode);
 549
 550                has_null_sha1 |= is_null_oid(oid);
 551                has_full_path |= !!strchr(name, '/');
 552                has_empty_name |= !*name;
 553                has_dot |= !strcmp(name, ".");
 554                has_dotdot |= !strcmp(name, "..");
 555                has_dotgit |= (!strcmp(name, ".git") ||
 556                               is_hfs_dotgit(name) ||
 557                               is_ntfs_dotgit(name));
 558                has_zero_pad |= *(char *)desc.buffer == '0';
 559                update_tree_entry(&desc);
 560
 561                switch (mode) {
 562                /*
 563                 * Standard modes..
 564                 */
 565                case S_IFREG | 0755:
 566                case S_IFREG | 0644:
 567                case S_IFLNK:
 568                case S_IFDIR:
 569                case S_IFGITLINK:
 570                        break;
 571                /*
 572                 * This is nonstandard, but we had a few of these
 573                 * early on when we honored the full set of mode
 574                 * bits..
 575                 */
 576                case S_IFREG | 0664:
 577                        if (!options->strict)
 578                                break;
 579                default:
 580                        has_bad_modes = 1;
 581                }
 582
 583                if (o_name) {
 584                        switch (verify_ordered(o_mode, o_name, mode, name)) {
 585                        case TREE_UNORDERED:
 586                                not_properly_sorted = 1;
 587                                break;
 588                        case TREE_HAS_DUPS:
 589                                has_dup_entries = 1;
 590                                break;
 591                        default:
 592                                break;
 593                        }
 594                }
 595
 596                o_mode = mode;
 597                o_name = name;
 598        }
 599
 600        retval = 0;
 601        if (has_null_sha1)
 602                retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 603        if (has_full_path)
 604                retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 605        if (has_empty_name)
 606                retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 607        if (has_dot)
 608                retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 609        if (has_dotdot)
 610                retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 611        if (has_dotgit)
 612                retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 613        if (has_zero_pad)
 614                retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 615        if (has_bad_modes)
 616                retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 617        if (has_dup_entries)
 618                retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 619        if (not_properly_sorted)
 620                retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 621        return retval;
 622}
 623
 624static int verify_headers(const void *data, unsigned long size,
 625                          struct object *obj, struct fsck_options *options)
 626{
 627        const char *buffer = (const char *)data;
 628        unsigned long i;
 629
 630        for (i = 0; i < size; i++) {
 631                switch (buffer[i]) {
 632                case '\0':
 633                        return report(options, obj,
 634                                FSCK_MSG_NUL_IN_HEADER,
 635                                "unterminated header: NUL at offset %ld", i);
 636                case '\n':
 637                        if (i + 1 < size && buffer[i + 1] == '\n')
 638                                return 0;
 639                }
 640        }
 641
 642        /*
 643         * We did not find double-LF that separates the header
 644         * and the body.  Not having a body is not a crime but
 645         * we do want to see the terminating LF for the last header
 646         * line.
 647         */
 648        if (size && buffer[size - 1] == '\n')
 649                return 0;
 650
 651        return report(options, obj,
 652                FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 653}
 654
 655static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 656{
 657        const char *p = *ident;
 658        char *end;
 659
 660        *ident = strchrnul(*ident, '\n');
 661        if (**ident == '\n')
 662                (*ident)++;
 663
 664        if (*p == '<')
 665                return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 666        p += strcspn(p, "<>\n");
 667        if (*p == '>')
 668                return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 669        if (*p != '<')
 670                return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 671        if (p[-1] != ' ')
 672                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 673        p++;
 674        p += strcspn(p, "<>\n");
 675        if (*p != '>')
 676                return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 677        p++;
 678        if (*p != ' ')
 679                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 680        p++;
 681        if (*p == '0' && p[1] != ' ')
 682                return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 683        if (date_overflows(strtoul(p, &end, 10)))
 684                return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 685        if ((end == p || *end != ' '))
 686                return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 687        p = end + 1;
 688        if ((*p != '+' && *p != '-') ||
 689            !isdigit(p[1]) ||
 690            !isdigit(p[2]) ||
 691            !isdigit(p[3]) ||
 692            !isdigit(p[4]) ||
 693            (p[5] != '\n'))
 694                return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 695        p += 6;
 696        return 0;
 697}
 698
 699static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 700        unsigned long size, struct fsck_options *options)
 701{
 702        unsigned char tree_sha1[20], sha1[20];
 703        struct commit_graft *graft;
 704        unsigned parent_count, parent_line_count = 0, author_count;
 705        int err;
 706        const char *buffer_begin = buffer;
 707
 708        if (verify_headers(buffer, size, &commit->object, options))
 709                return -1;
 710
 711        if (!skip_prefix(buffer, "tree ", &buffer))
 712                return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 713        if (get_sha1_hex(buffer, tree_sha1) || buffer[40] != '\n') {
 714                err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 715                if (err)
 716                        return err;
 717        }
 718        buffer += 41;
 719        while (skip_prefix(buffer, "parent ", &buffer)) {
 720                if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 721                        err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 722                        if (err)
 723                                return err;
 724                }
 725                buffer += 41;
 726                parent_line_count++;
 727        }
 728        graft = lookup_commit_graft(commit->object.oid.hash);
 729        parent_count = commit_list_count(commit->parents);
 730        if (graft) {
 731                if (graft->nr_parent == -1 && !parent_count)
 732                        ; /* shallow commit */
 733                else if (graft->nr_parent != parent_count) {
 734                        err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 735                        if (err)
 736                                return err;
 737                }
 738        } else {
 739                if (parent_count != parent_line_count) {
 740                        err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 741                        if (err)
 742                                return err;
 743                }
 744        }
 745        author_count = 0;
 746        while (skip_prefix(buffer, "author ", &buffer)) {
 747                author_count++;
 748                err = fsck_ident(&buffer, &commit->object, options);
 749                if (err)
 750                        return err;
 751        }
 752        if (author_count < 1)
 753                err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 754        else if (author_count > 1)
 755                err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 756        if (err)
 757                return err;
 758        if (!skip_prefix(buffer, "committer ", &buffer))
 759                return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 760        err = fsck_ident(&buffer, &commit->object, options);
 761        if (err)
 762                return err;
 763        if (!commit->tree) {
 764                err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", sha1_to_hex(tree_sha1));
 765                if (err)
 766                        return err;
 767        }
 768        if (memchr(buffer_begin, '\0', size)) {
 769                err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
 770                             "NUL byte in the commit object body");
 771                if (err)
 772                        return err;
 773        }
 774        return 0;
 775}
 776
 777static int fsck_commit(struct commit *commit, const char *data,
 778        unsigned long size, struct fsck_options *options)
 779{
 780        const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 781        int ret = fsck_commit_buffer(commit, buffer, size, options);
 782        if (!data)
 783                unuse_commit_buffer(commit, buffer);
 784        return ret;
 785}
 786
 787static int fsck_tag_buffer(struct tag *tag, const char *data,
 788        unsigned long size, struct fsck_options *options)
 789{
 790        unsigned char sha1[20];
 791        int ret = 0;
 792        const char *buffer;
 793        char *to_free = NULL, *eol;
 794        struct strbuf sb = STRBUF_INIT;
 795
 796        if (data)
 797                buffer = data;
 798        else {
 799                enum object_type type;
 800
 801                buffer = to_free =
 802                        read_sha1_file(tag->object.oid.hash, &type, &size);
 803                if (!buffer)
 804                        return report(options, &tag->object,
 805                                FSCK_MSG_MISSING_TAG_OBJECT,
 806                                "cannot read tag object");
 807
 808                if (type != OBJ_TAG) {
 809                        ret = report(options, &tag->object,
 810                                FSCK_MSG_TAG_OBJECT_NOT_TAG,
 811                                "expected tag got %s",
 812                            typename(type));
 813                        goto done;
 814                }
 815        }
 816
 817        ret = verify_headers(buffer, size, &tag->object, options);
 818        if (ret)
 819                goto done;
 820
 821        if (!skip_prefix(buffer, "object ", &buffer)) {
 822                ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 823                goto done;
 824        }
 825        if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 826                ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 827                if (ret)
 828                        goto done;
 829        }
 830        buffer += 41;
 831
 832        if (!skip_prefix(buffer, "type ", &buffer)) {
 833                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 834                goto done;
 835        }
 836        eol = strchr(buffer, '\n');
 837        if (!eol) {
 838                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 839                goto done;
 840        }
 841        if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 842                ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 843        if (ret)
 844                goto done;
 845        buffer = eol + 1;
 846
 847        if (!skip_prefix(buffer, "tag ", &buffer)) {
 848                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 849                goto done;
 850        }
 851        eol = strchr(buffer, '\n');
 852        if (!eol) {
 853                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 854                goto done;
 855        }
 856        strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 857        if (check_refname_format(sb.buf, 0)) {
 858                ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 859                           "invalid 'tag' name: %.*s",
 860                           (int)(eol - buffer), buffer);
 861                if (ret)
 862                        goto done;
 863        }
 864        buffer = eol + 1;
 865
 866        if (!skip_prefix(buffer, "tagger ", &buffer)) {
 867                /* early tags do not contain 'tagger' lines; warn only */
 868                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 869                if (ret)
 870                        goto done;
 871        }
 872        else
 873                ret = fsck_ident(&buffer, &tag->object, options);
 874
 875done:
 876        strbuf_release(&sb);
 877        free(to_free);
 878        return ret;
 879}
 880
 881static int fsck_tag(struct tag *tag, const char *data,
 882        unsigned long size, struct fsck_options *options)
 883{
 884        struct object *tagged = tag->tagged;
 885
 886        if (!tagged)
 887                return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 888
 889        return fsck_tag_buffer(tag, data, size, options);
 890}
 891
 892int fsck_object(struct object *obj, void *data, unsigned long size,
 893        struct fsck_options *options)
 894{
 895        if (!obj)
 896                return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
 897
 898        if (obj->type == OBJ_BLOB)
 899                return 0;
 900        if (obj->type == OBJ_TREE)
 901                return fsck_tree((struct tree *) obj, options);
 902        if (obj->type == OBJ_COMMIT)
 903                return fsck_commit((struct commit *) obj, (const char *) data,
 904                        size, options);
 905        if (obj->type == OBJ_TAG)
 906                return fsck_tag((struct tag *) obj, (const char *) data,
 907                        size, options);
 908
 909        return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
 910                          obj->type);
 911}
 912
 913int fsck_error_function(struct fsck_options *o,
 914        struct object *obj, int msg_type, const char *message)
 915{
 916        if (msg_type == FSCK_WARN) {
 917                warning("object %s: %s", describe_object(o, obj), message);
 918                return 0;
 919        }
 920        error("object %s: %s", describe_object(o, obj), message);
 921        return 1;
 922}