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