Imported Upstream version 2.22.2
[platform/upstream/git.git] / fsck.c
1 #include "cache.h"
2 #include "object-store.h"
3 #include "repository.h"
4 #include "object.h"
5 #include "blob.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "commit.h"
9 #include "tag.h"
10 #include "fsck.h"
11 #include "refs.h"
12 #include "utf8.h"
13 #include "decorate.h"
14 #include "oidset.h"
15 #include "packfile.h"
16 #include "submodule-config.h"
17 #include "config.h"
18 #include "help.h"
19
20 static struct oidset gitmodules_found = OIDSET_INIT;
21 static struct oidset gitmodules_done = OIDSET_INIT;
22
23 #define FSCK_FATAL -1
24 #define FSCK_INFO -2
25
26 #define FOREACH_MSG_ID(FUNC) \
27         /* fatal errors */ \
28         FUNC(NUL_IN_HEADER, FATAL) \
29         FUNC(UNTERMINATED_HEADER, FATAL) \
30         /* errors */ \
31         FUNC(BAD_DATE, ERROR) \
32         FUNC(BAD_DATE_OVERFLOW, ERROR) \
33         FUNC(BAD_EMAIL, ERROR) \
34         FUNC(BAD_NAME, ERROR) \
35         FUNC(BAD_OBJECT_SHA1, ERROR) \
36         FUNC(BAD_PARENT_SHA1, ERROR) \
37         FUNC(BAD_TAG_OBJECT, ERROR) \
38         FUNC(BAD_TIMEZONE, ERROR) \
39         FUNC(BAD_TREE, ERROR) \
40         FUNC(BAD_TREE_SHA1, ERROR) \
41         FUNC(BAD_TYPE, ERROR) \
42         FUNC(DUPLICATE_ENTRIES, ERROR) \
43         FUNC(MISSING_AUTHOR, ERROR) \
44         FUNC(MISSING_COMMITTER, ERROR) \
45         FUNC(MISSING_EMAIL, ERROR) \
46         FUNC(MISSING_GRAFT, ERROR) \
47         FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
48         FUNC(MISSING_OBJECT, ERROR) \
49         FUNC(MISSING_PARENT, ERROR) \
50         FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
51         FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
52         FUNC(MISSING_TAG, ERROR) \
53         FUNC(MISSING_TAG_ENTRY, ERROR) \
54         FUNC(MISSING_TAG_OBJECT, ERROR) \
55         FUNC(MISSING_TREE, ERROR) \
56         FUNC(MISSING_TREE_OBJECT, ERROR) \
57         FUNC(MISSING_TYPE, ERROR) \
58         FUNC(MISSING_TYPE_ENTRY, ERROR) \
59         FUNC(MULTIPLE_AUTHORS, ERROR) \
60         FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
61         FUNC(TREE_NOT_SORTED, ERROR) \
62         FUNC(UNKNOWN_TYPE, ERROR) \
63         FUNC(ZERO_PADDED_DATE, ERROR) \
64         FUNC(GITMODULES_MISSING, ERROR) \
65         FUNC(GITMODULES_BLOB, ERROR) \
66         FUNC(GITMODULES_LARGE, ERROR) \
67         FUNC(GITMODULES_NAME, ERROR) \
68         FUNC(GITMODULES_SYMLINK, ERROR) \
69         FUNC(GITMODULES_URL, ERROR) \
70         FUNC(GITMODULES_PATH, ERROR) \
71         FUNC(GITMODULES_UPDATE, ERROR) \
72         /* warnings */ \
73         FUNC(BAD_FILEMODE, WARN) \
74         FUNC(EMPTY_NAME, WARN) \
75         FUNC(FULL_PATHNAME, WARN) \
76         FUNC(HAS_DOT, WARN) \
77         FUNC(HAS_DOTDOT, WARN) \
78         FUNC(HAS_DOTGIT, WARN) \
79         FUNC(NULL_SHA1, WARN) \
80         FUNC(ZERO_PADDED_FILEMODE, WARN) \
81         FUNC(NUL_IN_COMMIT, WARN) \
82         /* infos (reported as warnings, but ignored by default) */ \
83         FUNC(GITMODULES_PARSE, INFO) \
84         FUNC(BAD_TAG_NAME, INFO) \
85         FUNC(MISSING_TAGGER_ENTRY, INFO)
86
87 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
88 enum fsck_msg_id {
89         FOREACH_MSG_ID(MSG_ID)
90         FSCK_MSG_MAX
91 };
92 #undef MSG_ID
93
94 #define STR(x) #x
95 #define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
96 static struct {
97         const char *id_string;
98         const char *downcased;
99         const char *camelcased;
100         int msg_type;
101 } msg_id_info[FSCK_MSG_MAX + 1] = {
102         FOREACH_MSG_ID(MSG_ID)
103         { NULL, NULL, NULL, -1 }
104 };
105 #undef MSG_ID
106
107 static void prepare_msg_ids(void)
108 {
109         int i;
110
111         if (msg_id_info[0].downcased)
112                 return;
113
114         /* convert id_string to lower case, without underscores. */
115         for (i = 0; i < FSCK_MSG_MAX; i++) {
116                 const char *p = msg_id_info[i].id_string;
117                 int len = strlen(p);
118                 char *q = xmalloc(len);
119
120                 msg_id_info[i].downcased = q;
121                 while (*p)
122                         if (*p == '_')
123                                 p++;
124                         else
125                                 *(q)++ = tolower(*(p)++);
126                 *q = '\0';
127
128                 p = msg_id_info[i].id_string;
129                 q = xmalloc(len);
130                 msg_id_info[i].camelcased = q;
131                 while (*p) {
132                         if (*p == '_') {
133                                 p++;
134                                 if (*p)
135                                         *q++ = *p++;
136                         } else {
137                                 *q++ = tolower(*p++);
138                         }
139                 }
140                 *q = '\0';
141         }
142 }
143
144 static int parse_msg_id(const char *text)
145 {
146         int i;
147
148         prepare_msg_ids();
149
150         for (i = 0; i < FSCK_MSG_MAX; i++)
151                 if (!strcmp(text, msg_id_info[i].downcased))
152                         return i;
153
154         return -1;
155 }
156
157 void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
158 {
159         int i;
160
161         prepare_msg_ids();
162
163         for (i = 0; i < FSCK_MSG_MAX; i++)
164                 list_config_item(list, prefix, msg_id_info[i].camelcased);
165 }
166
167 static int fsck_msg_type(enum fsck_msg_id msg_id,
168         struct fsck_options *options)
169 {
170         int msg_type;
171
172         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
173
174         if (options->msg_type)
175                 msg_type = options->msg_type[msg_id];
176         else {
177                 msg_type = msg_id_info[msg_id].msg_type;
178                 if (options->strict && msg_type == FSCK_WARN)
179                         msg_type = FSCK_ERROR;
180         }
181
182         return msg_type;
183 }
184
185 static void init_skiplist(struct fsck_options *options, const char *path)
186 {
187         FILE *fp;
188         struct strbuf sb = STRBUF_INIT;
189         struct object_id oid;
190
191         fp = fopen(path, "r");
192         if (!fp)
193                 die("Could not open skip list: %s", path);
194         while (!strbuf_getline(&sb, fp)) {
195                 const char *p;
196                 const char *hash;
197
198                 /*
199                  * Allow trailing comments, leading whitespace
200                  * (including before commits), and empty or whitespace
201                  * only lines.
202                  */
203                 hash = strchr(sb.buf, '#');
204                 if (hash)
205                         strbuf_setlen(&sb, hash - sb.buf);
206                 strbuf_trim(&sb);
207                 if (!sb.len)
208                         continue;
209
210                 if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0')
211                         die("Invalid SHA-1: %s", sb.buf);
212                 oidset_insert(&options->skiplist, &oid);
213         }
214         if (ferror(fp))
215                 die_errno("Could not read '%s'", path);
216         fclose(fp);
217         strbuf_release(&sb);
218 }
219
220 static int parse_msg_type(const char *str)
221 {
222         if (!strcmp(str, "error"))
223                 return FSCK_ERROR;
224         else if (!strcmp(str, "warn"))
225                 return FSCK_WARN;
226         else if (!strcmp(str, "ignore"))
227                 return FSCK_IGNORE;
228         else
229                 die("Unknown fsck message type: '%s'", str);
230 }
231
232 int is_valid_msg_type(const char *msg_id, const char *msg_type)
233 {
234         if (parse_msg_id(msg_id) < 0)
235                 return 0;
236         parse_msg_type(msg_type);
237         return 1;
238 }
239
240 void fsck_set_msg_type(struct fsck_options *options,
241                 const char *msg_id, const char *msg_type)
242 {
243         int id = parse_msg_id(msg_id), type;
244
245         if (id < 0)
246                 die("Unhandled message id: %s", msg_id);
247         type = parse_msg_type(msg_type);
248
249         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
250                 die("Cannot demote %s to %s", msg_id, msg_type);
251
252         if (!options->msg_type) {
253                 int i;
254                 int *msg_type;
255                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
256                 for (i = 0; i < FSCK_MSG_MAX; i++)
257                         msg_type[i] = fsck_msg_type(i, options);
258                 options->msg_type = msg_type;
259         }
260
261         options->msg_type[id] = type;
262 }
263
264 void fsck_set_msg_types(struct fsck_options *options, const char *values)
265 {
266         char *buf = xstrdup(values), *to_free = buf;
267         int done = 0;
268
269         while (!done) {
270                 int len = strcspn(buf, " ,|"), equal;
271
272                 done = !buf[len];
273                 if (!len) {
274                         buf++;
275                         continue;
276                 }
277                 buf[len] = '\0';
278
279                 for (equal = 0;
280                      equal < len && buf[equal] != '=' && buf[equal] != ':';
281                      equal++)
282                         buf[equal] = tolower(buf[equal]);
283                 buf[equal] = '\0';
284
285                 if (!strcmp(buf, "skiplist")) {
286                         if (equal == len)
287                                 die("skiplist requires a path");
288                         init_skiplist(options, buf + equal + 1);
289                         buf += len + 1;
290                         continue;
291                 }
292
293                 if (equal == len)
294                         die("Missing '=': '%s'", buf);
295
296                 fsck_set_msg_type(options, buf, buf + equal + 1);
297                 buf += len + 1;
298         }
299         free(to_free);
300 }
301
302 static void append_msg_id(struct strbuf *sb, const char *msg_id)
303 {
304         for (;;) {
305                 char c = *(msg_id)++;
306
307                 if (!c)
308                         break;
309                 if (c != '_')
310                         strbuf_addch(sb, tolower(c));
311                 else {
312                         assert(*msg_id);
313                         strbuf_addch(sb, *(msg_id)++);
314                 }
315         }
316
317         strbuf_addstr(sb, ": ");
318 }
319
320 static int object_on_skiplist(struct fsck_options *opts, struct object *obj)
321 {
322         return opts && obj && oidset_contains(&opts->skiplist, &obj->oid);
323 }
324
325 __attribute__((format (printf, 4, 5)))
326 static int report(struct fsck_options *options, struct object *object,
327         enum fsck_msg_id id, const char *fmt, ...)
328 {
329         va_list ap;
330         struct strbuf sb = STRBUF_INIT;
331         int msg_type = fsck_msg_type(id, options), result;
332
333         if (msg_type == FSCK_IGNORE)
334                 return 0;
335
336         if (object_on_skiplist(options, object))
337                 return 0;
338
339         if (msg_type == FSCK_FATAL)
340                 msg_type = FSCK_ERROR;
341         else if (msg_type == FSCK_INFO)
342                 msg_type = FSCK_WARN;
343
344         append_msg_id(&sb, msg_id_info[id].id_string);
345
346         va_start(ap, fmt);
347         strbuf_vaddf(&sb, fmt, ap);
348         result = options->error_func(options, object, msg_type, sb.buf);
349         strbuf_release(&sb);
350         va_end(ap);
351
352         return result;
353 }
354
355 static char *get_object_name(struct fsck_options *options, struct object *obj)
356 {
357         if (!options->object_names)
358                 return NULL;
359         return lookup_decoration(options->object_names, obj);
360 }
361
362 static void put_object_name(struct fsck_options *options, struct object *obj,
363         const char *fmt, ...)
364 {
365         va_list ap;
366         struct strbuf buf = STRBUF_INIT;
367         char *existing;
368
369         if (!options->object_names)
370                 return;
371         existing = lookup_decoration(options->object_names, obj);
372         if (existing)
373                 return;
374         va_start(ap, fmt);
375         strbuf_vaddf(&buf, fmt, ap);
376         add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
377         va_end(ap);
378 }
379
380 static const char *describe_object(struct fsck_options *o, struct object *obj)
381 {
382         static struct strbuf buf = STRBUF_INIT;
383         char *name;
384
385         strbuf_reset(&buf);
386         strbuf_addstr(&buf, oid_to_hex(&obj->oid));
387         if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
388                 strbuf_addf(&buf, " (%s)", name);
389
390         return buf.buf;
391 }
392
393 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
394 {
395         struct tree_desc desc;
396         struct name_entry entry;
397         int res = 0;
398         const char *name;
399
400         if (parse_tree(tree))
401                 return -1;
402
403         name = get_object_name(options, &tree->object);
404         if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
405                 return -1;
406         while (tree_entry_gently(&desc, &entry)) {
407                 struct object *obj;
408                 int result;
409
410                 if (S_ISGITLINK(entry.mode))
411                         continue;
412
413                 if (S_ISDIR(entry.mode)) {
414                         obj = (struct object *)lookup_tree(the_repository, &entry.oid);
415                         if (name && obj)
416                                 put_object_name(options, obj, "%s%s/", name,
417                                         entry.path);
418                         result = options->walk(obj, OBJ_TREE, data, options);
419                 }
420                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
421                         obj = (struct object *)lookup_blob(the_repository, &entry.oid);
422                         if (name && obj)
423                                 put_object_name(options, obj, "%s%s", name,
424                                         entry.path);
425                         result = options->walk(obj, OBJ_BLOB, data, options);
426                 }
427                 else {
428                         result = error("in tree %s: entry %s has bad mode %.6o",
429                                         describe_object(options, &tree->object), entry.path, entry.mode);
430                 }
431                 if (result < 0)
432                         return result;
433                 if (!res)
434                         res = result;
435         }
436         return res;
437 }
438
439 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
440 {
441         int counter = 0, generation = 0, name_prefix_len = 0;
442         struct commit_list *parents;
443         int res;
444         int result;
445         const char *name;
446
447         if (parse_commit(commit))
448                 return -1;
449
450         name = get_object_name(options, &commit->object);
451         if (name)
452                 put_object_name(options, &get_commit_tree(commit)->object,
453                                 "%s:", name);
454
455         result = options->walk((struct object *)get_commit_tree(commit),
456                                OBJ_TREE, data, options);
457         if (result < 0)
458                 return result;
459         res = result;
460
461         parents = commit->parents;
462         if (name && parents) {
463                 int len = strlen(name), power;
464
465                 if (len && name[len - 1] == '^') {
466                         generation = 1;
467                         name_prefix_len = len - 1;
468                 }
469                 else { /* parse ~<generation> suffix */
470                         for (generation = 0, power = 1;
471                              len && isdigit(name[len - 1]);
472                              power *= 10)
473                                 generation += power * (name[--len] - '0');
474                         if (power > 1 && len && name[len - 1] == '~')
475                                 name_prefix_len = len - 1;
476                 }
477         }
478
479         while (parents) {
480                 if (name) {
481                         struct object *obj = &parents->item->object;
482
483                         if (counter++)
484                                 put_object_name(options, obj, "%s^%d",
485                                         name, counter);
486                         else if (generation > 0)
487                                 put_object_name(options, obj, "%.*s~%d",
488                                         name_prefix_len, name, generation + 1);
489                         else
490                                 put_object_name(options, obj, "%s^", name);
491                 }
492                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
493                 if (result < 0)
494                         return result;
495                 if (!res)
496                         res = result;
497                 parents = parents->next;
498         }
499         return res;
500 }
501
502 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
503 {
504         char *name = get_object_name(options, &tag->object);
505
506         if (parse_tag(tag))
507                 return -1;
508         if (name)
509                 put_object_name(options, tag->tagged, "%s", name);
510         return options->walk(tag->tagged, OBJ_ANY, data, options);
511 }
512
513 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
514 {
515         if (!obj)
516                 return -1;
517
518         if (obj->type == OBJ_NONE)
519                 parse_object(the_repository, &obj->oid);
520
521         switch (obj->type) {
522         case OBJ_BLOB:
523                 return 0;
524         case OBJ_TREE:
525                 return fsck_walk_tree((struct tree *)obj, data, options);
526         case OBJ_COMMIT:
527                 return fsck_walk_commit((struct commit *)obj, data, options);
528         case OBJ_TAG:
529                 return fsck_walk_tag((struct tag *)obj, data, options);
530         default:
531                 error("Unknown object type for %s", describe_object(options, obj));
532                 return -1;
533         }
534 }
535
536 /*
537  * The entries in a tree are ordered in the _path_ order,
538  * which means that a directory entry is ordered by adding
539  * a slash to the end of it.
540  *
541  * So a directory called "a" is ordered _after_ a file
542  * called "a.c", because "a/" sorts after "a.c".
543  */
544 #define TREE_UNORDERED (-1)
545 #define TREE_HAS_DUPS  (-2)
546
547 static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
548 {
549         int len1 = strlen(name1);
550         int len2 = strlen(name2);
551         int len = len1 < len2 ? len1 : len2;
552         unsigned char c1, c2;
553         int cmp;
554
555         cmp = memcmp(name1, name2, len);
556         if (cmp < 0)
557                 return 0;
558         if (cmp > 0)
559                 return TREE_UNORDERED;
560
561         /*
562          * Ok, the first <len> characters are the same.
563          * Now we need to order the next one, but turn
564          * a '\0' into a '/' for a directory entry.
565          */
566         c1 = name1[len];
567         c2 = name2[len];
568         if (!c1 && !c2)
569                 /*
570                  * git-write-tree used to write out a nonsense tree that has
571                  * entries with the same name, one blob and one tree.  Make
572                  * sure we do not have duplicate entries.
573                  */
574                 return TREE_HAS_DUPS;
575         if (!c1 && S_ISDIR(mode1))
576                 c1 = '/';
577         if (!c2 && S_ISDIR(mode2))
578                 c2 = '/';
579         return c1 < c2 ? 0 : TREE_UNORDERED;
580 }
581
582 static int fsck_tree(struct tree *item, struct fsck_options *options)
583 {
584         int retval = 0;
585         int has_null_sha1 = 0;
586         int has_full_path = 0;
587         int has_empty_name = 0;
588         int has_dot = 0;
589         int has_dotdot = 0;
590         int has_dotgit = 0;
591         int has_zero_pad = 0;
592         int has_bad_modes = 0;
593         int has_dup_entries = 0;
594         int not_properly_sorted = 0;
595         struct tree_desc desc;
596         unsigned o_mode;
597         const char *o_name;
598
599         if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
600                 retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
601                 return retval;
602         }
603
604         o_mode = 0;
605         o_name = NULL;
606
607         while (desc.size) {
608                 unsigned short mode;
609                 const char *name, *backslash;
610                 const struct object_id *oid;
611
612                 oid = tree_entry_extract(&desc, &name, &mode);
613
614                 has_null_sha1 |= is_null_oid(oid);
615                 has_full_path |= !!strchr(name, '/');
616                 has_empty_name |= !*name;
617                 has_dot |= !strcmp(name, ".");
618                 has_dotdot |= !strcmp(name, "..");
619                 has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
620                 has_zero_pad |= *(char *)desc.buffer == '0';
621
622                 if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
623                         if (!S_ISLNK(mode))
624                                 oidset_insert(&gitmodules_found, oid);
625                         else
626                                 retval += report(options, &item->object,
627                                                  FSCK_MSG_GITMODULES_SYMLINK,
628                                                  ".gitmodules is a symbolic link");
629                 }
630
631                 if ((backslash = strchr(name, '\\'))) {
632                         while (backslash) {
633                                 backslash++;
634                                 has_dotgit |= is_ntfs_dotgit(backslash);
635                                 if (is_ntfs_dotgitmodules(backslash)) {
636                                         if (!S_ISLNK(mode))
637                                                 oidset_insert(&gitmodules_found, oid);
638                                         else
639                                                 retval += report(options, &item->object,
640                                                                  FSCK_MSG_GITMODULES_SYMLINK,
641                                                                  ".gitmodules is a symbolic link");
642                                 }
643                                 backslash = strchr(backslash, '\\');
644                         }
645                 }
646
647                 if (update_tree_entry_gently(&desc)) {
648                         retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
649                         break;
650                 }
651
652                 switch (mode) {
653                 /*
654                  * Standard modes..
655                  */
656                 case S_IFREG | 0755:
657                 case S_IFREG | 0644:
658                 case S_IFLNK:
659                 case S_IFDIR:
660                 case S_IFGITLINK:
661                         break;
662                 /*
663                  * This is nonstandard, but we had a few of these
664                  * early on when we honored the full set of mode
665                  * bits..
666                  */
667                 case S_IFREG | 0664:
668                         if (!options->strict)
669                                 break;
670                         /* fallthrough */
671                 default:
672                         has_bad_modes = 1;
673                 }
674
675                 if (o_name) {
676                         switch (verify_ordered(o_mode, o_name, mode, name)) {
677                         case TREE_UNORDERED:
678                                 not_properly_sorted = 1;
679                                 break;
680                         case TREE_HAS_DUPS:
681                                 has_dup_entries = 1;
682                                 break;
683                         default:
684                                 break;
685                         }
686                 }
687
688                 o_mode = mode;
689                 o_name = name;
690         }
691
692         if (has_null_sha1)
693                 retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
694         if (has_full_path)
695                 retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
696         if (has_empty_name)
697                 retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
698         if (has_dot)
699                 retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
700         if (has_dotdot)
701                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
702         if (has_dotgit)
703                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
704         if (has_zero_pad)
705                 retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
706         if (has_bad_modes)
707                 retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
708         if (has_dup_entries)
709                 retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
710         if (not_properly_sorted)
711                 retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
712         return retval;
713 }
714
715 static int verify_headers(const void *data, unsigned long size,
716                           struct object *obj, struct fsck_options *options)
717 {
718         const char *buffer = (const char *)data;
719         unsigned long i;
720
721         for (i = 0; i < size; i++) {
722                 switch (buffer[i]) {
723                 case '\0':
724                         return report(options, obj,
725                                 FSCK_MSG_NUL_IN_HEADER,
726                                 "unterminated header: NUL at offset %ld", i);
727                 case '\n':
728                         if (i + 1 < size && buffer[i + 1] == '\n')
729                                 return 0;
730                 }
731         }
732
733         /*
734          * We did not find double-LF that separates the header
735          * and the body.  Not having a body is not a crime but
736          * we do want to see the terminating LF for the last header
737          * line.
738          */
739         if (size && buffer[size - 1] == '\n')
740                 return 0;
741
742         return report(options, obj,
743                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
744 }
745
746 static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
747 {
748         const char *p = *ident;
749         char *end;
750
751         *ident = strchrnul(*ident, '\n');
752         if (**ident == '\n')
753                 (*ident)++;
754
755         if (*p == '<')
756                 return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
757         p += strcspn(p, "<>\n");
758         if (*p == '>')
759                 return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
760         if (*p != '<')
761                 return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
762         if (p[-1] != ' ')
763                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
764         p++;
765         p += strcspn(p, "<>\n");
766         if (*p != '>')
767                 return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
768         p++;
769         if (*p != ' ')
770                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
771         p++;
772         if (*p == '0' && p[1] != ' ')
773                 return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
774         if (date_overflows(parse_timestamp(p, &end, 10)))
775                 return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
776         if ((end == p || *end != ' '))
777                 return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
778         p = end + 1;
779         if ((*p != '+' && *p != '-') ||
780             !isdigit(p[1]) ||
781             !isdigit(p[2]) ||
782             !isdigit(p[3]) ||
783             !isdigit(p[4]) ||
784             (p[5] != '\n'))
785                 return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
786         p += 6;
787         return 0;
788 }
789
790 static int fsck_commit_buffer(struct commit *commit, const char *buffer,
791         unsigned long size, struct fsck_options *options)
792 {
793         struct object_id tree_oid, oid;
794         struct commit_graft *graft;
795         unsigned parent_count, parent_line_count = 0, author_count;
796         int err;
797         const char *buffer_begin = buffer;
798         const char *p;
799
800         if (verify_headers(buffer, size, &commit->object, options))
801                 return -1;
802
803         if (!skip_prefix(buffer, "tree ", &buffer))
804                 return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
805         if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
806                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
807                 if (err)
808                         return err;
809         }
810         buffer = p + 1;
811         while (skip_prefix(buffer, "parent ", &buffer)) {
812                 if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
813                         err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
814                         if (err)
815                                 return err;
816                 }
817                 buffer = p + 1;
818                 parent_line_count++;
819         }
820         graft = lookup_commit_graft(the_repository, &commit->object.oid);
821         parent_count = commit_list_count(commit->parents);
822         if (graft) {
823                 if (graft->nr_parent == -1 && !parent_count)
824                         ; /* shallow commit */
825                 else if (graft->nr_parent != parent_count) {
826                         err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
827                         if (err)
828                                 return err;
829                 }
830         } else {
831                 if (parent_count != parent_line_count) {
832                         err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
833                         if (err)
834                                 return err;
835                 }
836         }
837         author_count = 0;
838         while (skip_prefix(buffer, "author ", &buffer)) {
839                 author_count++;
840                 err = fsck_ident(&buffer, &commit->object, options);
841                 if (err)
842                         return err;
843         }
844         if (author_count < 1)
845                 err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
846         else if (author_count > 1)
847                 err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
848         if (err)
849                 return err;
850         if (!skip_prefix(buffer, "committer ", &buffer))
851                 return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
852         err = fsck_ident(&buffer, &commit->object, options);
853         if (err)
854                 return err;
855         if (!get_commit_tree(commit)) {
856                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", oid_to_hex(&tree_oid));
857                 if (err)
858                         return err;
859         }
860         if (memchr(buffer_begin, '\0', size)) {
861                 err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
862                              "NUL byte in the commit object body");
863                 if (err)
864                         return err;
865         }
866         return 0;
867 }
868
869 static int fsck_commit(struct commit *commit, const char *data,
870         unsigned long size, struct fsck_options *options)
871 {
872         const char *buffer = data ?  data : get_commit_buffer(commit, &size);
873         int ret = fsck_commit_buffer(commit, buffer, size, options);
874         if (!data)
875                 unuse_commit_buffer(commit, buffer);
876         return ret;
877 }
878
879 static int fsck_tag_buffer(struct tag *tag, const char *data,
880         unsigned long size, struct fsck_options *options)
881 {
882         struct object_id oid;
883         int ret = 0;
884         const char *buffer;
885         char *to_free = NULL, *eol;
886         struct strbuf sb = STRBUF_INIT;
887         const char *p;
888
889         if (data)
890                 buffer = data;
891         else {
892                 enum object_type type;
893
894                 buffer = to_free =
895                         read_object_file(&tag->object.oid, &type, &size);
896                 if (!buffer)
897                         return report(options, &tag->object,
898                                 FSCK_MSG_MISSING_TAG_OBJECT,
899                                 "cannot read tag object");
900
901                 if (type != OBJ_TAG) {
902                         ret = report(options, &tag->object,
903                                 FSCK_MSG_TAG_OBJECT_NOT_TAG,
904                                 "expected tag got %s",
905                             type_name(type));
906                         goto done;
907                 }
908         }
909
910         ret = verify_headers(buffer, size, &tag->object, options);
911         if (ret)
912                 goto done;
913
914         if (!skip_prefix(buffer, "object ", &buffer)) {
915                 ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
916                 goto done;
917         }
918         if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
919                 ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
920                 if (ret)
921                         goto done;
922         }
923         buffer = p + 1;
924
925         if (!skip_prefix(buffer, "type ", &buffer)) {
926                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
927                 goto done;
928         }
929         eol = strchr(buffer, '\n');
930         if (!eol) {
931                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
932                 goto done;
933         }
934         if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
935                 ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
936         if (ret)
937                 goto done;
938         buffer = eol + 1;
939
940         if (!skip_prefix(buffer, "tag ", &buffer)) {
941                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
942                 goto done;
943         }
944         eol = strchr(buffer, '\n');
945         if (!eol) {
946                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
947                 goto done;
948         }
949         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
950         if (check_refname_format(sb.buf, 0)) {
951                 ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
952                            "invalid 'tag' name: %.*s",
953                            (int)(eol - buffer), buffer);
954                 if (ret)
955                         goto done;
956         }
957         buffer = eol + 1;
958
959         if (!skip_prefix(buffer, "tagger ", &buffer)) {
960                 /* early tags do not contain 'tagger' lines; warn only */
961                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
962                 if (ret)
963                         goto done;
964         }
965         else
966                 ret = fsck_ident(&buffer, &tag->object, options);
967
968 done:
969         strbuf_release(&sb);
970         free(to_free);
971         return ret;
972 }
973
974 static int fsck_tag(struct tag *tag, const char *data,
975         unsigned long size, struct fsck_options *options)
976 {
977         struct object *tagged = tag->tagged;
978
979         if (!tagged)
980                 return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
981
982         return fsck_tag_buffer(tag, data, size, options);
983 }
984
985 struct fsck_gitmodules_data {
986         struct object *obj;
987         struct fsck_options *options;
988         int ret;
989 };
990
991 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
992 {
993         struct fsck_gitmodules_data *data = vdata;
994         const char *subsection, *key;
995         int subsection_len;
996         char *name;
997
998         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
999             !subsection)
1000                 return 0;
1001
1002         name = xmemdupz(subsection, subsection_len);
1003         if (check_submodule_name(name) < 0)
1004                 data->ret |= report(data->options, data->obj,
1005                                     FSCK_MSG_GITMODULES_NAME,
1006                                     "disallowed submodule name: %s",
1007                                     name);
1008         if (!strcmp(key, "url") && value &&
1009             looks_like_command_line_option(value))
1010                 data->ret |= report(data->options, data->obj,
1011                                     FSCK_MSG_GITMODULES_URL,
1012                                     "disallowed submodule url: %s",
1013                                     value);
1014         if (!strcmp(key, "path") && value &&
1015             looks_like_command_line_option(value))
1016                 data->ret |= report(data->options, data->obj,
1017                                     FSCK_MSG_GITMODULES_PATH,
1018                                     "disallowed submodule path: %s",
1019                                     value);
1020         if (!strcmp(key, "update") && value &&
1021             parse_submodule_update_type(value) == SM_UPDATE_COMMAND)
1022                 data->ret |= report(data->options, data->obj,
1023                                     FSCK_MSG_GITMODULES_UPDATE,
1024                                     "disallowed submodule update setting: %s",
1025                                     value);
1026         free(name);
1027
1028         return 0;
1029 }
1030
1031 static int fsck_blob(struct blob *blob, const char *buf,
1032                      unsigned long size, struct fsck_options *options)
1033 {
1034         struct fsck_gitmodules_data data;
1035         struct config_options config_opts = { 0 };
1036
1037         if (!oidset_contains(&gitmodules_found, &blob->object.oid))
1038                 return 0;
1039         oidset_insert(&gitmodules_done, &blob->object.oid);
1040
1041         if (object_on_skiplist(options, &blob->object))
1042                 return 0;
1043
1044         if (!buf) {
1045                 /*
1046                  * A missing buffer here is a sign that the caller found the
1047                  * blob too gigantic to load into memory. Let's just consider
1048                  * that an error.
1049                  */
1050                 return report(options, &blob->object,
1051                               FSCK_MSG_GITMODULES_LARGE,
1052                               ".gitmodules too large to parse");
1053         }
1054
1055         data.obj = &blob->object;
1056         data.options = options;
1057         data.ret = 0;
1058         config_opts.error_action = CONFIG_ERROR_SILENT;
1059         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1060                                 ".gitmodules", buf, size, &data, &config_opts))
1061                 data.ret |= report(options, &blob->object,
1062                                    FSCK_MSG_GITMODULES_PARSE,
1063                                    "could not parse gitmodules blob");
1064
1065         return data.ret;
1066 }
1067
1068 int fsck_object(struct object *obj, void *data, unsigned long size,
1069         struct fsck_options *options)
1070 {
1071         if (!obj)
1072                 return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1073
1074         if (obj->type == OBJ_BLOB)
1075                 return fsck_blob((struct blob *)obj, data, size, options);
1076         if (obj->type == OBJ_TREE)
1077                 return fsck_tree((struct tree *) obj, options);
1078         if (obj->type == OBJ_COMMIT)
1079                 return fsck_commit((struct commit *) obj, (const char *) data,
1080                         size, options);
1081         if (obj->type == OBJ_TAG)
1082                 return fsck_tag((struct tag *) obj, (const char *) data,
1083                         size, options);
1084
1085         return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
1086                           obj->type);
1087 }
1088
1089 int fsck_error_function(struct fsck_options *o,
1090         struct object *obj, int msg_type, const char *message)
1091 {
1092         if (msg_type == FSCK_WARN) {
1093                 warning("object %s: %s", describe_object(o, obj), message);
1094                 return 0;
1095         }
1096         error("object %s: %s", describe_object(o, obj), message);
1097         return 1;
1098 }
1099
1100 int fsck_finish(struct fsck_options *options)
1101 {
1102         int ret = 0;
1103         struct oidset_iter iter;
1104         const struct object_id *oid;
1105
1106         oidset_iter_init(&gitmodules_found, &iter);
1107         while ((oid = oidset_iter_next(&iter))) {
1108                 struct blob *blob;
1109                 enum object_type type;
1110                 unsigned long size;
1111                 char *buf;
1112
1113                 if (oidset_contains(&gitmodules_done, oid))
1114                         continue;
1115
1116                 blob = lookup_blob(the_repository, oid);
1117                 if (!blob) {
1118                         struct object *obj = lookup_unknown_object(oid->hash);
1119                         ret |= report(options, obj,
1120                                       FSCK_MSG_GITMODULES_BLOB,
1121                                       "non-blob found at .gitmodules");
1122                         continue;
1123                 }
1124
1125                 buf = read_object_file(oid, &type, &size);
1126                 if (!buf) {
1127                         if (is_promisor_object(&blob->object.oid))
1128                                 continue;
1129                         ret |= report(options, &blob->object,
1130                                       FSCK_MSG_GITMODULES_MISSING,
1131                                       "unable to read .gitmodules blob");
1132                         continue;
1133                 }
1134
1135                 if (type == OBJ_BLOB)
1136                         ret |= fsck_blob(blob, buf, size, options);
1137                 else
1138                         ret |= report(options, &blob->object,
1139                                       FSCK_MSG_GITMODULES_BLOB,
1140                                       "non-blob found at .gitmodules");
1141                 free(buf);
1142         }
1143
1144
1145         oidset_clear(&gitmodules_found);
1146         oidset_clear(&gitmodules_done);
1147         return ret;
1148 }