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