Andrew's git / gitweb.git / fsck.c
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fsck.con commit completion: keep other config var completion in camelCase (f45db83)
   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 "help.h"
  14
  15#define FSCK_FATAL -1
  16#define FSCK_INFO -2
  17
  18#define FOREACH_MSG_ID(FUNC) \
  19        /* fatal errors */ \
  20        FUNC(NUL_IN_HEADER, FATAL) \
  21        FUNC(UNTERMINATED_HEADER, FATAL) \
  22        /* errors */ \
  23        FUNC(BAD_DATE, ERROR) \
  24        FUNC(BAD_DATE_OVERFLOW, ERROR) \
  25        FUNC(BAD_EMAIL, ERROR) \
  26        FUNC(BAD_NAME, ERROR) \
  27        FUNC(BAD_OBJECT_SHA1, ERROR) \
  28        FUNC(BAD_PARENT_SHA1, ERROR) \
  29        FUNC(BAD_TAG_OBJECT, ERROR) \
  30        FUNC(BAD_TIMEZONE, ERROR) \
  31        FUNC(BAD_TREE, ERROR) \
  32        FUNC(BAD_TREE_SHA1, ERROR) \
  33        FUNC(BAD_TYPE, ERROR) \
  34        FUNC(DUPLICATE_ENTRIES, ERROR) \
  35        FUNC(MISSING_AUTHOR, ERROR) \
  36        FUNC(MISSING_COMMITTER, ERROR) \
  37        FUNC(MISSING_EMAIL, ERROR) \
  38        FUNC(MISSING_GRAFT, ERROR) \
  39        FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  40        FUNC(MISSING_OBJECT, ERROR) \
  41        FUNC(MISSING_PARENT, ERROR) \
  42        FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  43        FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  44        FUNC(MISSING_TAG, ERROR) \
  45        FUNC(MISSING_TAG_ENTRY, ERROR) \
  46        FUNC(MISSING_TAG_OBJECT, ERROR) \
  47        FUNC(MISSING_TREE, ERROR) \
  48        FUNC(MISSING_TYPE, ERROR) \
  49        FUNC(MISSING_TYPE_ENTRY, ERROR) \
  50        FUNC(MULTIPLE_AUTHORS, ERROR) \
  51        FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
  52        FUNC(TREE_NOT_SORTED, ERROR) \
  53        FUNC(UNKNOWN_TYPE, ERROR) \
  54        FUNC(ZERO_PADDED_DATE, ERROR) \
  55        /* warnings */ \
  56        FUNC(BAD_FILEMODE, WARN) \
  57        FUNC(EMPTY_NAME, WARN) \
  58        FUNC(FULL_PATHNAME, WARN) \
  59        FUNC(HAS_DOT, WARN) \
  60        FUNC(HAS_DOTDOT, WARN) \
  61        FUNC(HAS_DOTGIT, WARN) \
  62        FUNC(NULL_SHA1, WARN) \
  63        FUNC(ZERO_PADDED_FILEMODE, WARN) \
  64        FUNC(NUL_IN_COMMIT, WARN) \
  65        /* infos (reported as warnings, but ignored by default) */ \
  66        FUNC(BAD_TAG_NAME, INFO) \
  67        FUNC(MISSING_TAGGER_ENTRY, INFO)
  68
  69#define MSG_ID(id, msg_type) FSCK_MSG_##id,
  70enum fsck_msg_id {
  71        FOREACH_MSG_ID(MSG_ID)
  72        FSCK_MSG_MAX
  73};
  74#undef MSG_ID
  75
  76#define STR(x) #x
  77#define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
  78static struct {
  79        const char *id_string;
  80        const char *downcased;
  81        const char *camelcased;
  82        int msg_type;
  83} msg_id_info[FSCK_MSG_MAX + 1] = {
  84        FOREACH_MSG_ID(MSG_ID)
  85        { NULL, NULL, NULL, -1 }
  86};
  87#undef MSG_ID
  88
  89static void prepare_msg_ids(void)
  90{
  91        int i;
  92
  93        if (msg_id_info[0].downcased)
  94                return;
  95
  96        /* convert id_string to lower case, without underscores. */
  97        for (i = 0; i < FSCK_MSG_MAX; i++) {
  98                const char *p = msg_id_info[i].id_string;
  99                int len = strlen(p);
 100                char *q = xmalloc(len);
 101
 102                msg_id_info[i].downcased = q;
 103                while (*p)
 104                        if (*p == '_')
 105                                p++;
 106                        else
 107                                *(q)++ = tolower(*(p)++);
 108                *q = '\0';
 109
 110                p = msg_id_info[i].id_string;
 111                q = xmalloc(len);
 112                msg_id_info[i].camelcased = q;
 113                while (*p) {
 114                        if (*p == '_') {
 115                                p++;
 116                                if (*p)
 117                                        *q++ = *p++;
 118                        } else {
 119                                *q++ = tolower(*p++);
 120                        }
 121                }
 122                *q = '\0';
 123        }
 124}
 125
 126static int parse_msg_id(const char *text)
 127{
 128        int i;
 129
 130        prepare_msg_ids();
 131
 132        for (i = 0; i < FSCK_MSG_MAX; i++)
 133                if (!strcmp(text, msg_id_info[i].downcased))
 134                        return i;
 135
 136        return -1;
 137}
 138
 139void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
 140{
 141        int i;
 142
 143        prepare_msg_ids();
 144
 145        for (i = 0; i < FSCK_MSG_MAX; i++)
 146                list_config_item(list, prefix, msg_id_info[i].camelcased);
 147}
 148
 149static int fsck_msg_type(enum fsck_msg_id msg_id,
 150        struct fsck_options *options)
 151{
 152        int msg_type;
 153
 154        assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 155
 156        if (options->msg_type)
 157                msg_type = options->msg_type[msg_id];
 158        else {
 159                msg_type = msg_id_info[msg_id].msg_type;
 160                if (options->strict && msg_type == FSCK_WARN)
 161                        msg_type = FSCK_ERROR;
 162        }
 163
 164        return msg_type;
 165}
 166
 167static void init_skiplist(struct fsck_options *options, const char *path)
 168{
 169        static struct oid_array skiplist = OID_ARRAY_INIT;
 170        int sorted, fd;
 171        char buffer[GIT_MAX_HEXSZ + 1];
 172        struct object_id oid;
 173
 174        if (options->skiplist)
 175                sorted = options->skiplist->sorted;
 176        else {
 177                sorted = 1;
 178                options->skiplist = &skiplist;
 179        }
 180
 181        fd = open(path, O_RDONLY);
 182        if (fd < 0)
 183                die("Could not open skip list: %s", path);
 184        for (;;) {
 185                const char *p;
 186                int result = read_in_full(fd, buffer, sizeof(buffer));
 187                if (result < 0)
 188                        die_errno("Could not read '%s'", path);
 189                if (!result)
 190                        break;
 191                if (parse_oid_hex(buffer, &oid, &p) || *p != '\n')
 192                        die("Invalid SHA-1: %s", buffer);
 193                oid_array_append(&skiplist, &oid);
 194                if (sorted && skiplist.nr > 1 &&
 195                                oidcmp(&skiplist.oid[skiplist.nr - 2],
 196                                       &oid) > 0)
 197                        sorted = 0;
 198        }
 199        close(fd);
 200
 201        if (sorted)
 202                skiplist.sorted = 1;
 203}
 204
 205static int parse_msg_type(const char *str)
 206{
 207        if (!strcmp(str, "error"))
 208                return FSCK_ERROR;
 209        else if (!strcmp(str, "warn"))
 210                return FSCK_WARN;
 211        else if (!strcmp(str, "ignore"))
 212                return FSCK_IGNORE;
 213        else
 214                die("Unknown fsck message type: '%s'", str);
 215}
 216
 217int is_valid_msg_type(const char *msg_id, const char *msg_type)
 218{
 219        if (parse_msg_id(msg_id) < 0)
 220                return 0;
 221        parse_msg_type(msg_type);
 222        return 1;
 223}
 224
 225void fsck_set_msg_type(struct fsck_options *options,
 226                const char *msg_id, const char *msg_type)
 227{
 228        int id = parse_msg_id(msg_id), type;
 229
 230        if (id < 0)
 231                die("Unhandled message id: %s", msg_id);
 232        type = parse_msg_type(msg_type);
 233
 234        if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
 235                die("Cannot demote %s to %s", msg_id, msg_type);
 236
 237        if (!options->msg_type) {
 238                int i;
 239                int *msg_type;
 240                ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
 241                for (i = 0; i < FSCK_MSG_MAX; i++)
 242                        msg_type[i] = fsck_msg_type(i, options);
 243                options->msg_type = msg_type;
 244        }
 245
 246        options->msg_type[id] = type;
 247}
 248
 249void fsck_set_msg_types(struct fsck_options *options, const char *values)
 250{
 251        char *buf = xstrdup(values), *to_free = buf;
 252        int done = 0;
 253
 254        while (!done) {
 255                int len = strcspn(buf, " ,|"), equal;
 256
 257                done = !buf[len];
 258                if (!len) {
 259                        buf++;
 260                        continue;
 261                }
 262                buf[len] = '\0';
 263
 264                for (equal = 0;
 265                     equal < len && buf[equal] != '=' && buf[equal] != ':';
 266                     equal++)
 267                        buf[equal] = tolower(buf[equal]);
 268                buf[equal] = '\0';
 269
 270                if (!strcmp(buf, "skiplist")) {
 271                        if (equal == len)
 272                                die("skiplist requires a path");
 273                        init_skiplist(options, buf + equal + 1);
 274                        buf += len + 1;
 275                        continue;
 276                }
 277
 278                if (equal == len)
 279                        die("Missing '=': '%s'", buf);
 280
 281                fsck_set_msg_type(options, buf, buf + equal + 1);
 282                buf += len + 1;
 283        }
 284        free(to_free);
 285}
 286
 287static void append_msg_id(struct strbuf *sb, const char *msg_id)
 288{
 289        for (;;) {
 290                char c = *(msg_id)++;
 291
 292                if (!c)
 293                        break;
 294                if (c != '_')
 295                        strbuf_addch(sb, tolower(c));
 296                else {
 297                        assert(*msg_id);
 298                        strbuf_addch(sb, *(msg_id)++);
 299                }
 300        }
 301
 302        strbuf_addstr(sb, ": ");
 303}
 304
 305__attribute__((format (printf, 4, 5)))
 306static int report(struct fsck_options *options, struct object *object,
 307        enum fsck_msg_id id, const char *fmt, ...)
 308{
 309        va_list ap;
 310        struct strbuf sb = STRBUF_INIT;
 311        int msg_type = fsck_msg_type(id, options), result;
 312
 313        if (msg_type == FSCK_IGNORE)
 314                return 0;
 315
 316        if (options->skiplist && object &&
 317                        oid_array_lookup(options->skiplist, &object->oid) >= 0)
 318                return 0;
 319
 320        if (msg_type == FSCK_FATAL)
 321                msg_type = FSCK_ERROR;
 322        else if (msg_type == FSCK_INFO)
 323                msg_type = FSCK_WARN;
 324
 325        append_msg_id(&sb, msg_id_info[id].id_string);
 326
 327        va_start(ap, fmt);
 328        strbuf_vaddf(&sb, fmt, ap);
 329        result = options->error_func(options, object, msg_type, sb.buf);
 330        strbuf_release(&sb);
 331        va_end(ap);
 332
 333        return result;
 334}
 335
 336static char *get_object_name(struct fsck_options *options, struct object *obj)
 337{
 338        if (!options->object_names)
 339                return NULL;
 340        return lookup_decoration(options->object_names, obj);
 341}
 342
 343static void put_object_name(struct fsck_options *options, struct object *obj,
 344        const char *fmt, ...)
 345{
 346        va_list ap;
 347        struct strbuf buf = STRBUF_INIT;
 348        char *existing;
 349
 350        if (!options->object_names)
 351                return;
 352        existing = lookup_decoration(options->object_names, obj);
 353        if (existing)
 354                return;
 355        va_start(ap, fmt);
 356        strbuf_vaddf(&buf, fmt, ap);
 357        add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
 358        va_end(ap);
 359}
 360
 361static const char *describe_object(struct fsck_options *o, struct object *obj)
 362{
 363        static struct strbuf buf = STRBUF_INIT;
 364        char *name;
 365
 366        strbuf_reset(&buf);
 367        strbuf_addstr(&buf, oid_to_hex(&obj->oid));
 368        if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
 369                strbuf_addf(&buf, " (%s)", name);
 370
 371        return buf.buf;
 372}
 373
 374static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 375{
 376        struct tree_desc desc;
 377        struct name_entry entry;
 378        int res = 0;
 379        const char *name;
 380
 381        if (parse_tree(tree))
 382                return -1;
 383
 384        name = get_object_name(options, &tree->object);
 385        if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
 386                return -1;
 387        while (tree_entry_gently(&desc, &entry)) {
 388                struct object *obj;
 389                int result;
 390
 391                if (S_ISGITLINK(entry.mode))
 392                        continue;
 393
 394                if (S_ISDIR(entry.mode)) {
 395                        obj = (struct object *)lookup_tree(entry.oid);
 396                        if (name && obj)
 397                                put_object_name(options, obj, "%s%s/", name,
 398                                        entry.path);
 399                        result = options->walk(obj, OBJ_TREE, data, options);
 400                }
 401                else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
 402                        obj = (struct object *)lookup_blob(entry.oid);
 403                        if (name && obj)
 404                                put_object_name(options, obj, "%s%s", name,
 405                                        entry.path);
 406                        result = options->walk(obj, OBJ_BLOB, data, options);
 407                }
 408                else {
 409                        result = error("in tree %s: entry %s has bad mode %.6o",
 410                                        describe_object(options, &tree->object), entry.path, entry.mode);
 411                }
 412                if (result < 0)
 413                        return result;
 414                if (!res)
 415                        res = result;
 416        }
 417        return res;
 418}
 419
 420static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 421{
 422        int counter = 0, generation = 0, name_prefix_len = 0;
 423        struct commit_list *parents;
 424        int res;
 425        int result;
 426        const char *name;
 427
 428        if (parse_commit(commit))
 429                return -1;
 430
 431        name = get_object_name(options, &commit->object);
 432        if (name)
 433                put_object_name(options, &get_commit_tree(commit)->object,
 434                                "%s:", name);
 435
 436        result = options->walk((struct object *)get_commit_tree(commit),
 437                               OBJ_TREE, data, options);
 438        if (result < 0)
 439                return result;
 440        res = result;
 441
 442        parents = commit->parents;
 443        if (name && parents) {
 444                int len = strlen(name), power;
 445
 446                if (len && name[len - 1] == '^') {
 447                        generation = 1;
 448                        name_prefix_len = len - 1;
 449                }
 450                else { /* parse ~<generation> suffix */
 451                        for (generation = 0, power = 1;
 452                             len && isdigit(name[len - 1]);
 453                             power *= 10)
 454                                generation += power * (name[--len] - '0');
 455                        if (power > 1 && len && name[len - 1] == '~')
 456                                name_prefix_len = len - 1;
 457                }
 458        }
 459
 460        while (parents) {
 461                if (name) {
 462                        struct object *obj = &parents->item->object;
 463
 464                        if (++counter > 1)
 465                                put_object_name(options, obj, "%s^%d",
 466                                        name, counter);
 467                        else if (generation > 0)
 468                                put_object_name(options, obj, "%.*s~%d",
 469                                        name_prefix_len, name, generation + 1);
 470                        else
 471                                put_object_name(options, obj, "%s^", name);
 472                }
 473                result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 474                if (result < 0)
 475                        return result;
 476                if (!res)
 477                        res = result;
 478                parents = parents->next;
 479        }
 480        return res;
 481}
 482
 483static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 484{
 485        char *name = get_object_name(options, &tag->object);
 486
 487        if (parse_tag(tag))
 488                return -1;
 489        if (name)
 490                put_object_name(options, tag->tagged, "%s", name);
 491        return options->walk(tag->tagged, OBJ_ANY, data, options);
 492}
 493
 494int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 495{
 496        if (!obj)
 497                return -1;
 498
 499        if (obj->type == OBJ_NONE)
 500                parse_object(&obj->oid);
 501
 502        switch (obj->type) {
 503        case OBJ_BLOB:
 504                return 0;
 505        case OBJ_TREE:
 506                return fsck_walk_tree((struct tree *)obj, data, options);
 507        case OBJ_COMMIT:
 508                return fsck_walk_commit((struct commit *)obj, data, options);
 509        case OBJ_TAG:
 510                return fsck_walk_tag((struct tag *)obj, data, options);
 511        default:
 512                error("Unknown object type for %s", describe_object(options, obj));
 513                return -1;
 514        }
 515}
 516
 517/*
 518 * The entries in a tree are ordered in the _path_ order,
 519 * which means that a directory entry is ordered by adding
 520 * a slash to the end of it.
 521 *
 522 * So a directory called "a" is ordered _after_ a file
 523 * called "a.c", because "a/" sorts after "a.c".
 524 */
 525#define TREE_UNORDERED (-1)
 526#define TREE_HAS_DUPS  (-2)
 527
 528static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 529{
 530        int len1 = strlen(name1);
 531        int len2 = strlen(name2);
 532        int len = len1 < len2 ? len1 : len2;
 533        unsigned char c1, c2;
 534        int cmp;
 535
 536        cmp = memcmp(name1, name2, len);
 537        if (cmp < 0)
 538                return 0;
 539        if (cmp > 0)
 540                return TREE_UNORDERED;
 541
 542        /*
 543         * Ok, the first <len> characters are the same.
 544         * Now we need to order the next one, but turn
 545         * a '\0' into a '/' for a directory entry.
 546         */
 547        c1 = name1[len];
 548        c2 = name2[len];
 549        if (!c1 && !c2)
 550                /*
 551                 * git-write-tree used to write out a nonsense tree that has
 552                 * entries with the same name, one blob and one tree.  Make
 553                 * sure we do not have duplicate entries.
 554                 */
 555                return TREE_HAS_DUPS;
 556        if (!c1 && S_ISDIR(mode1))
 557                c1 = '/';
 558        if (!c2 && S_ISDIR(mode2))
 559                c2 = '/';
 560        return c1 < c2 ? 0 : TREE_UNORDERED;
 561}
 562
 563static int fsck_tree(struct tree *item, struct fsck_options *options)
 564{
 565        int retval = 0;
 566        int has_null_sha1 = 0;
 567        int has_full_path = 0;
 568        int has_empty_name = 0;
 569        int has_dot = 0;
 570        int has_dotdot = 0;
 571        int has_dotgit = 0;
 572        int has_zero_pad = 0;
 573        int has_bad_modes = 0;
 574        int has_dup_entries = 0;
 575        int not_properly_sorted = 0;
 576        struct tree_desc desc;
 577        unsigned o_mode;
 578        const char *o_name;
 579
 580        if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
 581                retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 582                return retval;
 583        }
 584
 585        o_mode = 0;
 586        o_name = NULL;
 587
 588        while (desc.size) {
 589                unsigned mode;
 590                const char *name;
 591                const struct object_id *oid;
 592
 593                oid = tree_entry_extract(&desc, &name, &mode);
 594
 595                has_null_sha1 |= is_null_oid(oid);
 596                has_full_path |= !!strchr(name, '/');
 597                has_empty_name |= !*name;
 598                has_dot |= !strcmp(name, ".");
 599                has_dotdot |= !strcmp(name, "..");
 600                has_dotgit |= (!strcmp(name, ".git") ||
 601                               is_hfs_dotgit(name) ||
 602                               is_ntfs_dotgit(name));
 603                has_zero_pad |= *(char *)desc.buffer == '0';
 604                if (update_tree_entry_gently(&desc)) {
 605                        retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 606                        break;
 607                }
 608
 609                switch (mode) {
 610                /*
 611                 * Standard modes..
 612                 */
 613                case S_IFREG | 0755:
 614                case S_IFREG | 0644:
 615                case S_IFLNK:
 616                case S_IFDIR:
 617                case S_IFGITLINK:
 618                        break;
 619                /*
 620                 * This is nonstandard, but we had a few of these
 621                 * early on when we honored the full set of mode
 622                 * bits..
 623                 */
 624                case S_IFREG | 0664:
 625                        if (!options->strict)
 626                                break;
 627                        /* fallthrough */
 628                default:
 629                        has_bad_modes = 1;
 630                }
 631
 632                if (o_name) {
 633                        switch (verify_ordered(o_mode, o_name, mode, name)) {
 634                        case TREE_UNORDERED:
 635                                not_properly_sorted = 1;
 636                                break;
 637                        case TREE_HAS_DUPS:
 638                                has_dup_entries = 1;
 639                                break;
 640                        default:
 641                                break;
 642                        }
 643                }
 644
 645                o_mode = mode;
 646                o_name = name;
 647        }
 648
 649        if (has_null_sha1)
 650                retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 651        if (has_full_path)
 652                retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 653        if (has_empty_name)
 654                retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 655        if (has_dot)
 656                retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 657        if (has_dotdot)
 658                retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 659        if (has_dotgit)
 660                retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 661        if (has_zero_pad)
 662                retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 663        if (has_bad_modes)
 664                retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 665        if (has_dup_entries)
 666                retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 667        if (not_properly_sorted)
 668                retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 669        return retval;
 670}
 671
 672static int verify_headers(const void *data, unsigned long size,
 673                          struct object *obj, struct fsck_options *options)
 674{
 675        const char *buffer = (const char *)data;
 676        unsigned long i;
 677
 678        for (i = 0; i < size; i++) {
 679                switch (buffer[i]) {
 680                case '\0':
 681                        return report(options, obj,
 682                                FSCK_MSG_NUL_IN_HEADER,
 683                                "unterminated header: NUL at offset %ld", i);
 684                case '\n':
 685                        if (i + 1 < size && buffer[i + 1] == '\n')
 686                                return 0;
 687                }
 688        }
 689
 690        /*
 691         * We did not find double-LF that separates the header
 692         * and the body.  Not having a body is not a crime but
 693         * we do want to see the terminating LF for the last header
 694         * line.
 695         */
 696        if (size && buffer[size - 1] == '\n')
 697                return 0;
 698
 699        return report(options, obj,
 700                FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 701}
 702
 703static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 704{
 705        const char *p = *ident;
 706        char *end;
 707
 708        *ident = strchrnul(*ident, '\n');
 709        if (**ident == '\n')
 710                (*ident)++;
 711
 712        if (*p == '<')
 713                return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 714        p += strcspn(p, "<>\n");
 715        if (*p == '>')
 716                return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 717        if (*p != '<')
 718                return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 719        if (p[-1] != ' ')
 720                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 721        p++;
 722        p += strcspn(p, "<>\n");
 723        if (*p != '>')
 724                return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 725        p++;
 726        if (*p != ' ')
 727                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 728        p++;
 729        if (*p == '0' && p[1] != ' ')
 730                return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 731        if (date_overflows(parse_timestamp(p, &end, 10)))
 732                return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 733        if ((end == p || *end != ' '))
 734                return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 735        p = end + 1;
 736        if ((*p != '+' && *p != '-') ||
 737            !isdigit(p[1]) ||
 738            !isdigit(p[2]) ||
 739            !isdigit(p[3]) ||
 740            !isdigit(p[4]) ||
 741            (p[5] != '\n'))
 742                return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 743        p += 6;
 744        return 0;
 745}
 746
 747static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 748        unsigned long size, struct fsck_options *options)
 749{
 750        unsigned char tree_sha1[20], sha1[20];
 751        struct commit_graft *graft;
 752        unsigned parent_count, parent_line_count = 0, author_count;
 753        int err;
 754        const char *buffer_begin = buffer;
 755
 756        if (verify_headers(buffer, size, &commit->object, options))
 757                return -1;
 758
 759        if (!skip_prefix(buffer, "tree ", &buffer))
 760                return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 761        if (get_sha1_hex(buffer, tree_sha1) || buffer[40] != '\n') {
 762                err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 763                if (err)
 764                        return err;
 765        }
 766        buffer += 41;
 767        while (skip_prefix(buffer, "parent ", &buffer)) {
 768                if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 769                        err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 770                        if (err)
 771                                return err;
 772                }
 773                buffer += 41;
 774                parent_line_count++;
 775        }
 776        graft = lookup_commit_graft(&commit->object.oid);
 777        parent_count = commit_list_count(commit->parents);
 778        if (graft) {
 779                if (graft->nr_parent == -1 && !parent_count)
 780                        ; /* shallow commit */
 781                else if (graft->nr_parent != parent_count) {
 782                        err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 783                        if (err)
 784                                return err;
 785                }
 786        } else {
 787                if (parent_count != parent_line_count) {
 788                        err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 789                        if (err)
 790                                return err;
 791                }
 792        }
 793        author_count = 0;
 794        while (skip_prefix(buffer, "author ", &buffer)) {
 795                author_count++;
 796                err = fsck_ident(&buffer, &commit->object, options);
 797                if (err)
 798                        return err;
 799        }
 800        if (author_count < 1)
 801                err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 802        else if (author_count > 1)
 803                err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 804        if (err)
 805                return err;
 806        if (!skip_prefix(buffer, "committer ", &buffer))
 807                return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 808        err = fsck_ident(&buffer, &commit->object, options);
 809        if (err)
 810                return err;
 811        if (!get_commit_tree(commit)) {
 812                err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", sha1_to_hex(tree_sha1));
 813                if (err)
 814                        return err;
 815        }
 816        if (memchr(buffer_begin, '\0', size)) {
 817                err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
 818                             "NUL byte in the commit object body");
 819                if (err)
 820                        return err;
 821        }
 822        return 0;
 823}
 824
 825static int fsck_commit(struct commit *commit, const char *data,
 826        unsigned long size, struct fsck_options *options)
 827{
 828        const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 829        int ret = fsck_commit_buffer(commit, buffer, size, options);
 830        if (!data)
 831                unuse_commit_buffer(commit, buffer);
 832        return ret;
 833}
 834
 835static int fsck_tag_buffer(struct tag *tag, const char *data,
 836        unsigned long size, struct fsck_options *options)
 837{
 838        unsigned char sha1[20];
 839        int ret = 0;
 840        const char *buffer;
 841        char *to_free = NULL, *eol;
 842        struct strbuf sb = STRBUF_INIT;
 843
 844        if (data)
 845                buffer = data;
 846        else {
 847                enum object_type type;
 848
 849                buffer = to_free =
 850                        read_object_file(&tag->object.oid, &type, &size);
 851                if (!buffer)
 852                        return report(options, &tag->object,
 853                                FSCK_MSG_MISSING_TAG_OBJECT,
 854                                "cannot read tag object");
 855
 856                if (type != OBJ_TAG) {
 857                        ret = report(options, &tag->object,
 858                                FSCK_MSG_TAG_OBJECT_NOT_TAG,
 859                                "expected tag got %s",
 860                            type_name(type));
 861                        goto done;
 862                }
 863        }
 864
 865        ret = verify_headers(buffer, size, &tag->object, options);
 866        if (ret)
 867                goto done;
 868
 869        if (!skip_prefix(buffer, "object ", &buffer)) {
 870                ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 871                goto done;
 872        }
 873        if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 874                ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 875                if (ret)
 876                        goto done;
 877        }
 878        buffer += 41;
 879
 880        if (!skip_prefix(buffer, "type ", &buffer)) {
 881                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 882                goto done;
 883        }
 884        eol = strchr(buffer, '\n');
 885        if (!eol) {
 886                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 887                goto done;
 888        }
 889        if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 890                ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 891        if (ret)
 892                goto done;
 893        buffer = eol + 1;
 894
 895        if (!skip_prefix(buffer, "tag ", &buffer)) {
 896                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 897                goto done;
 898        }
 899        eol = strchr(buffer, '\n');
 900        if (!eol) {
 901                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 902                goto done;
 903        }
 904        strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 905        if (check_refname_format(sb.buf, 0)) {
 906                ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 907                           "invalid 'tag' name: %.*s",
 908                           (int)(eol - buffer), buffer);
 909                if (ret)
 910                        goto done;
 911        }
 912        buffer = eol + 1;
 913
 914        if (!skip_prefix(buffer, "tagger ", &buffer)) {
 915                /* early tags do not contain 'tagger' lines; warn only */
 916                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 917                if (ret)
 918                        goto done;
 919        }
 920        else
 921                ret = fsck_ident(&buffer, &tag->object, options);
 922
 923done:
 924        strbuf_release(&sb);
 925        free(to_free);
 926        return ret;
 927}
 928
 929static int fsck_tag(struct tag *tag, const char *data,
 930        unsigned long size, struct fsck_options *options)
 931{
 932        struct object *tagged = tag->tagged;
 933
 934        if (!tagged)
 935                return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 936
 937        return fsck_tag_buffer(tag, data, size, options);
 938}
 939
 940int fsck_object(struct object *obj, void *data, unsigned long size,
 941        struct fsck_options *options)
 942{
 943        if (!obj)
 944                return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
 945
 946        if (obj->type == OBJ_BLOB)
 947                return 0;
 948        if (obj->type == OBJ_TREE)
 949                return fsck_tree((struct tree *) obj, options);
 950        if (obj->type == OBJ_COMMIT)
 951                return fsck_commit((struct commit *) obj, (const char *) data,
 952                        size, options);
 953        if (obj->type == OBJ_TAG)
 954                return fsck_tag((struct tag *) obj, (const char *) data,
 955                        size, options);
 956
 957        return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
 958                          obj->type);
 959}
 960
 961int fsck_error_function(struct fsck_options *o,
 962        struct object *obj, int msg_type, const char *message)
 963{
 964        if (msg_type == FSCK_WARN) {
 965                warning("object %s: %s", describe_object(o, obj), message);
 966                return 0;
 967        }
 968        error("object %s: %s", describe_object(o, obj), message);
 969        return 1;
 970}