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