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