Imported Upstream version 2.22.3
[platform/upstream/git.git] / fsck.c
1 #include "cache.h"
2 #include "object-store.h"
3 #include "repository.h"
4 #include "object.h"
5 #include "blob.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "commit.h"
9 #include "tag.h"
10 #include "fsck.h"
11 #include "refs.h"
12 #include "utf8.h"
13 #include "decorate.h"
14 #include "oidset.h"
15 #include "packfile.h"
16 #include "submodule-config.h"
17 #include "config.h"
18 #include "credential.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_LARGE, ERROR) \
68         FUNC(GITMODULES_NAME, ERROR) \
69         FUNC(GITMODULES_SYMLINK, ERROR) \
70         FUNC(GITMODULES_URL, ERROR) \
71         FUNC(GITMODULES_PATH, ERROR) \
72         FUNC(GITMODULES_UPDATE, ERROR) \
73         /* warnings */ \
74         FUNC(BAD_FILEMODE, WARN) \
75         FUNC(EMPTY_NAME, WARN) \
76         FUNC(FULL_PATHNAME, WARN) \
77         FUNC(HAS_DOT, WARN) \
78         FUNC(HAS_DOTDOT, WARN) \
79         FUNC(HAS_DOTGIT, WARN) \
80         FUNC(NULL_SHA1, WARN) \
81         FUNC(ZERO_PADDED_FILEMODE, WARN) \
82         FUNC(NUL_IN_COMMIT, WARN) \
83         /* infos (reported as warnings, but ignored by default) */ \
84         FUNC(GITMODULES_PARSE, INFO) \
85         FUNC(BAD_TAG_NAME, INFO) \
86         FUNC(MISSING_TAGGER_ENTRY, INFO)
87
88 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
89 enum fsck_msg_id {
90         FOREACH_MSG_ID(MSG_ID)
91         FSCK_MSG_MAX
92 };
93 #undef MSG_ID
94
95 #define STR(x) #x
96 #define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
97 static struct {
98         const char *id_string;
99         const char *downcased;
100         const char *camelcased;
101         int msg_type;
102 } msg_id_info[FSCK_MSG_MAX + 1] = {
103         FOREACH_MSG_ID(MSG_ID)
104         { NULL, NULL, NULL, -1 }
105 };
106 #undef MSG_ID
107
108 static void prepare_msg_ids(void)
109 {
110         int i;
111
112         if (msg_id_info[0].downcased)
113                 return;
114
115         /* convert id_string to lower case, without underscores. */
116         for (i = 0; i < FSCK_MSG_MAX; i++) {
117                 const char *p = msg_id_info[i].id_string;
118                 int len = strlen(p);
119                 char *q = xmalloc(len);
120
121                 msg_id_info[i].downcased = q;
122                 while (*p)
123                         if (*p == '_')
124                                 p++;
125                         else
126                                 *(q)++ = tolower(*(p)++);
127                 *q = '\0';
128
129                 p = msg_id_info[i].id_string;
130                 q = xmalloc(len);
131                 msg_id_info[i].camelcased = q;
132                 while (*p) {
133                         if (*p == '_') {
134                                 p++;
135                                 if (*p)
136                                         *q++ = *p++;
137                         } else {
138                                 *q++ = tolower(*p++);
139                         }
140                 }
141                 *q = '\0';
142         }
143 }
144
145 static int parse_msg_id(const char *text)
146 {
147         int i;
148
149         prepare_msg_ids();
150
151         for (i = 0; i < FSCK_MSG_MAX; i++)
152                 if (!strcmp(text, msg_id_info[i].downcased))
153                         return i;
154
155         return -1;
156 }
157
158 void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
159 {
160         int i;
161
162         prepare_msg_ids();
163
164         for (i = 0; i < FSCK_MSG_MAX; i++)
165                 list_config_item(list, prefix, msg_id_info[i].camelcased);
166 }
167
168 static int fsck_msg_type(enum fsck_msg_id msg_id,
169         struct fsck_options *options)
170 {
171         int msg_type;
172
173         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
174
175         if (options->msg_type)
176                 msg_type = options->msg_type[msg_id];
177         else {
178                 msg_type = msg_id_info[msg_id].msg_type;
179                 if (options->strict && msg_type == FSCK_WARN)
180                         msg_type = FSCK_ERROR;
181         }
182
183         return msg_type;
184 }
185
186 static void init_skiplist(struct fsck_options *options, const char *path)
187 {
188         FILE *fp;
189         struct strbuf sb = STRBUF_INIT;
190         struct object_id oid;
191
192         fp = fopen(path, "r");
193         if (!fp)
194                 die("Could not open skip list: %s", path);
195         while (!strbuf_getline(&sb, fp)) {
196                 const char *p;
197                 const char *hash;
198
199                 /*
200                  * Allow trailing comments, leading whitespace
201                  * (including before commits), and empty or whitespace
202                  * only lines.
203                  */
204                 hash = strchr(sb.buf, '#');
205                 if (hash)
206                         strbuf_setlen(&sb, hash - sb.buf);
207                 strbuf_trim(&sb);
208                 if (!sb.len)
209                         continue;
210
211                 if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0')
212                         die("Invalid SHA-1: %s", sb.buf);
213                 oidset_insert(&options->skiplist, &oid);
214         }
215         if (ferror(fp))
216                 die_errno("Could not read '%s'", path);
217         fclose(fp);
218         strbuf_release(&sb);
219 }
220
221 static int parse_msg_type(const char *str)
222 {
223         if (!strcmp(str, "error"))
224                 return FSCK_ERROR;
225         else if (!strcmp(str, "warn"))
226                 return FSCK_WARN;
227         else if (!strcmp(str, "ignore"))
228                 return FSCK_IGNORE;
229         else
230                 die("Unknown fsck message type: '%s'", str);
231 }
232
233 int is_valid_msg_type(const char *msg_id, const char *msg_type)
234 {
235         if (parse_msg_id(msg_id) < 0)
236                 return 0;
237         parse_msg_type(msg_type);
238         return 1;
239 }
240
241 void fsck_set_msg_type(struct fsck_options *options,
242                 const char *msg_id, const char *msg_type)
243 {
244         int id = parse_msg_id(msg_id), type;
245
246         if (id < 0)
247                 die("Unhandled message id: %s", msg_id);
248         type = parse_msg_type(msg_type);
249
250         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
251                 die("Cannot demote %s to %s", msg_id, msg_type);
252
253         if (!options->msg_type) {
254                 int i;
255                 int *msg_type;
256                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
257                 for (i = 0; i < FSCK_MSG_MAX; i++)
258                         msg_type[i] = fsck_msg_type(i, options);
259                 options->msg_type = msg_type;
260         }
261
262         options->msg_type[id] = type;
263 }
264
265 void fsck_set_msg_types(struct fsck_options *options, const char *values)
266 {
267         char *buf = xstrdup(values), *to_free = buf;
268         int done = 0;
269
270         while (!done) {
271                 int len = strcspn(buf, " ,|"), equal;
272
273                 done = !buf[len];
274                 if (!len) {
275                         buf++;
276                         continue;
277                 }
278                 buf[len] = '\0';
279
280                 for (equal = 0;
281                      equal < len && buf[equal] != '=' && buf[equal] != ':';
282                      equal++)
283                         buf[equal] = tolower(buf[equal]);
284                 buf[equal] = '\0';
285
286                 if (!strcmp(buf, "skiplist")) {
287                         if (equal == len)
288                                 die("skiplist requires a path");
289                         init_skiplist(options, buf + equal + 1);
290                         buf += len + 1;
291                         continue;
292                 }
293
294                 if (equal == len)
295                         die("Missing '=': '%s'", buf);
296
297                 fsck_set_msg_type(options, buf, buf + equal + 1);
298                 buf += len + 1;
299         }
300         free(to_free);
301 }
302
303 static void append_msg_id(struct strbuf *sb, const char *msg_id)
304 {
305         for (;;) {
306                 char c = *(msg_id)++;
307
308                 if (!c)
309                         break;
310                 if (c != '_')
311                         strbuf_addch(sb, tolower(c));
312                 else {
313                         assert(*msg_id);
314                         strbuf_addch(sb, *(msg_id)++);
315                 }
316         }
317
318         strbuf_addstr(sb, ": ");
319 }
320
321 static int object_on_skiplist(struct fsck_options *opts, struct object *obj)
322 {
323         return opts && obj && oidset_contains(&opts->skiplist, &obj->oid);
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(the_repository, &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(the_repository, &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++)
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(the_repository, &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 short mode;
610                 const char *name, *backslash;
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 ((backslash = strchr(name, '\\'))) {
633                         while (backslash) {
634                                 backslash++;
635                                 has_dotgit |= is_ntfs_dotgit(backslash);
636                                 if (is_ntfs_dotgitmodules(backslash)) {
637                                         if (!S_ISLNK(mode))
638                                                 oidset_insert(&gitmodules_found, oid);
639                                         else
640                                                 retval += report(options, &item->object,
641                                                                  FSCK_MSG_GITMODULES_SYMLINK,
642                                                                  ".gitmodules is a symbolic link");
643                                 }
644                                 backslash = strchr(backslash, '\\');
645                         }
646                 }
647
648                 if (update_tree_entry_gently(&desc)) {
649                         retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
650                         break;
651                 }
652
653                 switch (mode) {
654                 /*
655                  * Standard modes..
656                  */
657                 case S_IFREG | 0755:
658                 case S_IFREG | 0644:
659                 case S_IFLNK:
660                 case S_IFDIR:
661                 case S_IFGITLINK:
662                         break;
663                 /*
664                  * This is nonstandard, but we had a few of these
665                  * early on when we honored the full set of mode
666                  * bits..
667                  */
668                 case S_IFREG | 0664:
669                         if (!options->strict)
670                                 break;
671                         /* fallthrough */
672                 default:
673                         has_bad_modes = 1;
674                 }
675
676                 if (o_name) {
677                         switch (verify_ordered(o_mode, o_name, mode, name)) {
678                         case TREE_UNORDERED:
679                                 not_properly_sorted = 1;
680                                 break;
681                         case TREE_HAS_DUPS:
682                                 has_dup_entries = 1;
683                                 break;
684                         default:
685                                 break;
686                         }
687                 }
688
689                 o_mode = mode;
690                 o_name = name;
691         }
692
693         if (has_null_sha1)
694                 retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
695         if (has_full_path)
696                 retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
697         if (has_empty_name)
698                 retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
699         if (has_dot)
700                 retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
701         if (has_dotdot)
702                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
703         if (has_dotgit)
704                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
705         if (has_zero_pad)
706                 retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
707         if (has_bad_modes)
708                 retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
709         if (has_dup_entries)
710                 retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
711         if (not_properly_sorted)
712                 retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
713         return retval;
714 }
715
716 static int verify_headers(const void *data, unsigned long size,
717                           struct object *obj, struct fsck_options *options)
718 {
719         const char *buffer = (const char *)data;
720         unsigned long i;
721
722         for (i = 0; i < size; i++) {
723                 switch (buffer[i]) {
724                 case '\0':
725                         return report(options, obj,
726                                 FSCK_MSG_NUL_IN_HEADER,
727                                 "unterminated header: NUL at offset %ld", i);
728                 case '\n':
729                         if (i + 1 < size && buffer[i + 1] == '\n')
730                                 return 0;
731                 }
732         }
733
734         /*
735          * We did not find double-LF that separates the header
736          * and the body.  Not having a body is not a crime but
737          * we do want to see the terminating LF for the last header
738          * line.
739          */
740         if (size && buffer[size - 1] == '\n')
741                 return 0;
742
743         return report(options, obj,
744                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
745 }
746
747 static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
748 {
749         const char *p = *ident;
750         char *end;
751
752         *ident = strchrnul(*ident, '\n');
753         if (**ident == '\n')
754                 (*ident)++;
755
756         if (*p == '<')
757                 return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
758         p += strcspn(p, "<>\n");
759         if (*p == '>')
760                 return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
761         if (*p != '<')
762                 return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
763         if (p[-1] != ' ')
764                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
765         p++;
766         p += strcspn(p, "<>\n");
767         if (*p != '>')
768                 return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
769         p++;
770         if (*p != ' ')
771                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
772         p++;
773         if (*p == '0' && p[1] != ' ')
774                 return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
775         if (date_overflows(parse_timestamp(p, &end, 10)))
776                 return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
777         if ((end == p || *end != ' '))
778                 return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
779         p = end + 1;
780         if ((*p != '+' && *p != '-') ||
781             !isdigit(p[1]) ||
782             !isdigit(p[2]) ||
783             !isdigit(p[3]) ||
784             !isdigit(p[4]) ||
785             (p[5] != '\n'))
786                 return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
787         p += 6;
788         return 0;
789 }
790
791 static int fsck_commit_buffer(struct commit *commit, const char *buffer,
792         unsigned long size, struct fsck_options *options)
793 {
794         struct object_id tree_oid, oid;
795         struct commit_graft *graft;
796         unsigned parent_count, parent_line_count = 0, author_count;
797         int err;
798         const char *buffer_begin = buffer;
799         const char *p;
800
801         if (verify_headers(buffer, size, &commit->object, options))
802                 return -1;
803
804         if (!skip_prefix(buffer, "tree ", &buffer))
805                 return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
806         if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
807                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
808                 if (err)
809                         return err;
810         }
811         buffer = p + 1;
812         while (skip_prefix(buffer, "parent ", &buffer)) {
813                 if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
814                         err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
815                         if (err)
816                                 return err;
817                 }
818                 buffer = p + 1;
819                 parent_line_count++;
820         }
821         graft = lookup_commit_graft(the_repository, &commit->object.oid);
822         parent_count = commit_list_count(commit->parents);
823         if (graft) {
824                 if (graft->nr_parent == -1 && !parent_count)
825                         ; /* shallow commit */
826                 else if (graft->nr_parent != parent_count) {
827                         err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
828                         if (err)
829                                 return err;
830                 }
831         } else {
832                 if (parent_count != parent_line_count) {
833                         err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
834                         if (err)
835                                 return err;
836                 }
837         }
838         author_count = 0;
839         while (skip_prefix(buffer, "author ", &buffer)) {
840                 author_count++;
841                 err = fsck_ident(&buffer, &commit->object, options);
842                 if (err)
843                         return err;
844         }
845         if (author_count < 1)
846                 err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
847         else if (author_count > 1)
848                 err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
849         if (err)
850                 return err;
851         if (!skip_prefix(buffer, "committer ", &buffer))
852                 return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
853         err = fsck_ident(&buffer, &commit->object, options);
854         if (err)
855                 return err;
856         if (!get_commit_tree(commit)) {
857                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", oid_to_hex(&tree_oid));
858                 if (err)
859                         return err;
860         }
861         if (memchr(buffer_begin, '\0', size)) {
862                 err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
863                              "NUL byte in the commit object body");
864                 if (err)
865                         return err;
866         }
867         return 0;
868 }
869
870 static int fsck_commit(struct commit *commit, const char *data,
871         unsigned long size, struct fsck_options *options)
872 {
873         const char *buffer = data ?  data : get_commit_buffer(commit, &size);
874         int ret = fsck_commit_buffer(commit, buffer, size, options);
875         if (!data)
876                 unuse_commit_buffer(commit, buffer);
877         return ret;
878 }
879
880 static int fsck_tag_buffer(struct tag *tag, const char *data,
881         unsigned long size, struct fsck_options *options)
882 {
883         struct object_id oid;
884         int ret = 0;
885         const char *buffer;
886         char *to_free = NULL, *eol;
887         struct strbuf sb = STRBUF_INIT;
888         const char *p;
889
890         if (data)
891                 buffer = data;
892         else {
893                 enum object_type type;
894
895                 buffer = to_free =
896                         read_object_file(&tag->object.oid, &type, &size);
897                 if (!buffer)
898                         return report(options, &tag->object,
899                                 FSCK_MSG_MISSING_TAG_OBJECT,
900                                 "cannot read tag object");
901
902                 if (type != OBJ_TAG) {
903                         ret = report(options, &tag->object,
904                                 FSCK_MSG_TAG_OBJECT_NOT_TAG,
905                                 "expected tag got %s",
906                             type_name(type));
907                         goto done;
908                 }
909         }
910
911         ret = verify_headers(buffer, size, &tag->object, options);
912         if (ret)
913                 goto done;
914
915         if (!skip_prefix(buffer, "object ", &buffer)) {
916                 ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
917                 goto done;
918         }
919         if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
920                 ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
921                 if (ret)
922                         goto done;
923         }
924         buffer = p + 1;
925
926         if (!skip_prefix(buffer, "type ", &buffer)) {
927                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
928                 goto done;
929         }
930         eol = strchr(buffer, '\n');
931         if (!eol) {
932                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
933                 goto done;
934         }
935         if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
936                 ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
937         if (ret)
938                 goto done;
939         buffer = eol + 1;
940
941         if (!skip_prefix(buffer, "tag ", &buffer)) {
942                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
943                 goto done;
944         }
945         eol = strchr(buffer, '\n');
946         if (!eol) {
947                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
948                 goto done;
949         }
950         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
951         if (check_refname_format(sb.buf, 0)) {
952                 ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
953                            "invalid 'tag' name: %.*s",
954                            (int)(eol - buffer), buffer);
955                 if (ret)
956                         goto done;
957         }
958         buffer = eol + 1;
959
960         if (!skip_prefix(buffer, "tagger ", &buffer)) {
961                 /* early tags do not contain 'tagger' lines; warn only */
962                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
963                 if (ret)
964                         goto done;
965         }
966         else
967                 ret = fsck_ident(&buffer, &tag->object, options);
968
969 done:
970         strbuf_release(&sb);
971         free(to_free);
972         return ret;
973 }
974
975 static int fsck_tag(struct tag *tag, const char *data,
976         unsigned long size, struct fsck_options *options)
977 {
978         struct object *tagged = tag->tagged;
979
980         if (!tagged)
981                 return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
982
983         return fsck_tag_buffer(tag, data, size, options);
984 }
985
986 static int check_submodule_url(const char *url)
987 {
988         struct credential c = CREDENTIAL_INIT;
989         int ret;
990
991         if (looks_like_command_line_option(url))
992                 return -1;
993
994         ret = credential_from_url_gently(&c, url, 1);
995         credential_clear(&c);
996         return ret;
997 }
998
999 struct fsck_gitmodules_data {
1000         struct object *obj;
1001         struct fsck_options *options;
1002         int ret;
1003 };
1004
1005 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
1006 {
1007         struct fsck_gitmodules_data *data = vdata;
1008         const char *subsection, *key;
1009         int subsection_len;
1010         char *name;
1011
1012         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
1013             !subsection)
1014                 return 0;
1015
1016         name = xmemdupz(subsection, subsection_len);
1017         if (check_submodule_name(name) < 0)
1018                 data->ret |= report(data->options, data->obj,
1019                                     FSCK_MSG_GITMODULES_NAME,
1020                                     "disallowed submodule name: %s",
1021                                     name);
1022         if (!strcmp(key, "url") && value &&
1023             check_submodule_url(value) < 0)
1024                 data->ret |= report(data->options, data->obj,
1025                                     FSCK_MSG_GITMODULES_URL,
1026                                     "disallowed submodule url: %s",
1027                                     value);
1028         if (!strcmp(key, "path") && value &&
1029             looks_like_command_line_option(value))
1030                 data->ret |= report(data->options, data->obj,
1031                                     FSCK_MSG_GITMODULES_PATH,
1032                                     "disallowed submodule path: %s",
1033                                     value);
1034         if (!strcmp(key, "update") && value &&
1035             parse_submodule_update_type(value) == SM_UPDATE_COMMAND)
1036                 data->ret |= report(data->options, data->obj,
1037                                     FSCK_MSG_GITMODULES_UPDATE,
1038                                     "disallowed submodule update setting: %s",
1039                                     value);
1040         free(name);
1041
1042         return 0;
1043 }
1044
1045 static int fsck_blob(struct blob *blob, const char *buf,
1046                      unsigned long size, struct fsck_options *options)
1047 {
1048         struct fsck_gitmodules_data data;
1049         struct config_options config_opts = { 0 };
1050
1051         if (!oidset_contains(&gitmodules_found, &blob->object.oid))
1052                 return 0;
1053         oidset_insert(&gitmodules_done, &blob->object.oid);
1054
1055         if (object_on_skiplist(options, &blob->object))
1056                 return 0;
1057
1058         if (!buf) {
1059                 /*
1060                  * A missing buffer here is a sign that the caller found the
1061                  * blob too gigantic to load into memory. Let's just consider
1062                  * that an error.
1063                  */
1064                 return report(options, &blob->object,
1065                               FSCK_MSG_GITMODULES_LARGE,
1066                               ".gitmodules too large to parse");
1067         }
1068
1069         data.obj = &blob->object;
1070         data.options = options;
1071         data.ret = 0;
1072         config_opts.error_action = CONFIG_ERROR_SILENT;
1073         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1074                                 ".gitmodules", buf, size, &data, &config_opts))
1075                 data.ret |= report(options, &blob->object,
1076                                    FSCK_MSG_GITMODULES_PARSE,
1077                                    "could not parse gitmodules blob");
1078
1079         return data.ret;
1080 }
1081
1082 int fsck_object(struct object *obj, void *data, unsigned long size,
1083         struct fsck_options *options)
1084 {
1085         if (!obj)
1086                 return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1087
1088         if (obj->type == OBJ_BLOB)
1089                 return fsck_blob((struct blob *)obj, data, size, options);
1090         if (obj->type == OBJ_TREE)
1091                 return fsck_tree((struct tree *) obj, options);
1092         if (obj->type == OBJ_COMMIT)
1093                 return fsck_commit((struct commit *) obj, (const char *) data,
1094                         size, options);
1095         if (obj->type == OBJ_TAG)
1096                 return fsck_tag((struct tag *) obj, (const char *) data,
1097                         size, options);
1098
1099         return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
1100                           obj->type);
1101 }
1102
1103 int fsck_error_function(struct fsck_options *o,
1104         struct object *obj, int msg_type, const char *message)
1105 {
1106         if (msg_type == FSCK_WARN) {
1107                 warning("object %s: %s", describe_object(o, obj), message);
1108                 return 0;
1109         }
1110         error("object %s: %s", describe_object(o, obj), message);
1111         return 1;
1112 }
1113
1114 int fsck_finish(struct fsck_options *options)
1115 {
1116         int ret = 0;
1117         struct oidset_iter iter;
1118         const struct object_id *oid;
1119
1120         oidset_iter_init(&gitmodules_found, &iter);
1121         while ((oid = oidset_iter_next(&iter))) {
1122                 struct blob *blob;
1123                 enum object_type type;
1124                 unsigned long size;
1125                 char *buf;
1126
1127                 if (oidset_contains(&gitmodules_done, oid))
1128                         continue;
1129
1130                 blob = lookup_blob(the_repository, oid);
1131                 if (!blob) {
1132                         struct object *obj = lookup_unknown_object(oid->hash);
1133                         ret |= report(options, obj,
1134                                       FSCK_MSG_GITMODULES_BLOB,
1135                                       "non-blob found at .gitmodules");
1136                         continue;
1137                 }
1138
1139                 buf = read_object_file(oid, &type, &size);
1140                 if (!buf) {
1141                         if (is_promisor_object(&blob->object.oid))
1142                                 continue;
1143                         ret |= report(options, &blob->object,
1144                                       FSCK_MSG_GITMODULES_MISSING,
1145                                       "unable to read .gitmodules blob");
1146                         continue;
1147                 }
1148
1149                 if (type == OBJ_BLOB)
1150                         ret |= fsck_blob(blob, buf, size, options);
1151                 else
1152                         ret |= report(options, &blob->object,
1153                                       FSCK_MSG_GITMODULES_BLOB,
1154                                       "non-blob found at .gitmodules");
1155                 free(buf);
1156         }
1157
1158
1159         oidset_clear(&gitmodules_found);
1160         oidset_clear(&gitmodules_done);
1161         return ret;
1162 }