Merge branch 'maint-1.6.1' into maint
[git/git.git] / builtin-fsck.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "commit.h"
4 #include "tree.h"
5 #include "blob.h"
6 #include "tag.h"
7 #include "refs.h"
8 #include "pack.h"
9 #include "cache-tree.h"
10 #include "tree-walk.h"
11 #include "fsck.h"
12 #include "parse-options.h"
13 #include "dir.h"
14
15 #define REACHABLE 0x0001
16 #define SEEN 0x0002
17
18 static int show_root;
19 static int show_tags;
20 static int show_unreachable;
21 static int include_reflogs = 1;
22 static int check_full;
23 static int check_strict;
24 static int keep_cache_objects;
25 static unsigned char head_sha1[20];
26 static const char *head_points_at;
27 static int errors_found;
28 static int write_lost_and_found;
29 static int verbose;
30 #define ERROR_OBJECT 01
31 #define ERROR_REACHABLE 02
32
33 #ifdef NO_D_INO_IN_DIRENT
34 #define SORT_DIRENT 0
35 #define DIRENT_SORT_HINT(de) 0
36 #else
37 #define SORT_DIRENT 1
38 #define DIRENT_SORT_HINT(de) ((de)->d_ino)
39 #endif
40
41 static void objreport(struct object *obj, const char *severity,
42 const char *err, va_list params)
43 {
44 fprintf(stderr, "%s in %s %s: ",
45 severity, typename(obj->type), sha1_to_hex(obj->sha1));
46 vfprintf(stderr, err, params);
47 fputs("\n", stderr);
48 }
49
50 static int objerror(struct object *obj, const char *err, ...)
51 {
52 va_list params;
53 va_start(params, err);
54 errors_found |= ERROR_OBJECT;
55 objreport(obj, "error", err, params);
56 va_end(params);
57 return -1;
58 }
59
60 static int fsck_error_func(struct object *obj, int type, const char *err, ...)
61 {
62 va_list params;
63 va_start(params, err);
64 objreport(obj, (type == FSCK_WARN) ? "warning" : "error", err, params);
65 va_end(params);
66 return (type == FSCK_WARN) ? 0 : 1;
67 }
68
69 static struct object_array pending;
70
71 static int mark_object(struct object *obj, int type, void *data)
72 {
73 struct object *parent = data;
74
75 if (!obj) {
76 printf("broken link from %7s %s\n",
77 typename(parent->type), sha1_to_hex(parent->sha1));
78 printf("broken link from %7s %s\n",
79 (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
80 errors_found |= ERROR_REACHABLE;
81 return 1;
82 }
83
84 if (type != OBJ_ANY && obj->type != type)
85 objerror(parent, "wrong object type in link");
86
87 if (obj->flags & REACHABLE)
88 return 0;
89 obj->flags |= REACHABLE;
90 if (!obj->parsed) {
91 if (parent && !has_sha1_file(obj->sha1)) {
92 printf("broken link from %7s %s\n",
93 typename(parent->type), sha1_to_hex(parent->sha1));
94 printf(" to %7s %s\n",
95 typename(obj->type), sha1_to_hex(obj->sha1));
96 errors_found |= ERROR_REACHABLE;
97 }
98 return 1;
99 }
100
101 add_object_array(obj, (void *) parent, &pending);
102 return 0;
103 }
104
105 static void mark_object_reachable(struct object *obj)
106 {
107 mark_object(obj, OBJ_ANY, 0);
108 }
109
110 static int traverse_one_object(struct object *obj, struct object *parent)
111 {
112 int result;
113 struct tree *tree = NULL;
114
115 if (obj->type == OBJ_TREE) {
116 obj->parsed = 0;
117 tree = (struct tree *)obj;
118 if (parse_tree(tree) < 0)
119 return 1; /* error already displayed */
120 }
121 result = fsck_walk(obj, mark_object, obj);
122 if (tree) {
123 free(tree->buffer);
124 tree->buffer = NULL;
125 }
126 return result;
127 }
128
129 static int traverse_reachable(void)
130 {
131 int result = 0;
132 while (pending.nr) {
133 struct object_array_entry *entry;
134 struct object *obj, *parent;
135
136 entry = pending.objects + --pending.nr;
137 obj = entry->item;
138 parent = (struct object *) entry->name;
139 result |= traverse_one_object(obj, parent);
140 }
141 return !!result;
142 }
143
144 static int mark_used(struct object *obj, int type, void *data)
145 {
146 if (!obj)
147 return 1;
148 obj->used = 1;
149 return 0;
150 }
151
152 /*
153 * Check a single reachable object
154 */
155 static void check_reachable_object(struct object *obj)
156 {
157 /*
158 * We obviously want the object to be parsed,
159 * except if it was in a pack-file and we didn't
160 * do a full fsck
161 */
162 if (!obj->parsed) {
163 if (has_sha1_pack(obj->sha1))
164 return; /* it is in pack - forget about it */
165 printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
166 errors_found |= ERROR_REACHABLE;
167 return;
168 }
169 }
170
171 /*
172 * Check a single unreachable object
173 */
174 static void check_unreachable_object(struct object *obj)
175 {
176 /*
177 * Missing unreachable object? Ignore it. It's not like
178 * we miss it (since it can't be reached), nor do we want
179 * to complain about it being unreachable (since it does
180 * not exist).
181 */
182 if (!obj->parsed)
183 return;
184
185 /*
186 * Unreachable object that exists? Show it if asked to,
187 * since this is something that is prunable.
188 */
189 if (show_unreachable) {
190 printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
191 return;
192 }
193
194 /*
195 * "!used" means that nothing at all points to it, including
196 * other unreachable objects. In other words, it's the "tip"
197 * of some set of unreachable objects, usually a commit that
198 * got dropped.
199 *
200 * Such starting points are more interesting than some random
201 * set of unreachable objects, so we show them even if the user
202 * hasn't asked for _all_ unreachable objects. If you have
203 * deleted a branch by mistake, this is a prime candidate to
204 * start looking at, for example.
205 */
206 if (!obj->used) {
207 printf("dangling %s %s\n", typename(obj->type),
208 sha1_to_hex(obj->sha1));
209 if (write_lost_and_found) {
210 char *filename = git_path("lost-found/%s/%s",
211 obj->type == OBJ_COMMIT ? "commit" : "other",
212 sha1_to_hex(obj->sha1));
213 FILE *f;
214
215 if (safe_create_leading_directories(filename)) {
216 error("Could not create lost-found");
217 return;
218 }
219 if (!(f = fopen(filename, "w")))
220 die("Could not open %s", filename);
221 if (obj->type == OBJ_BLOB) {
222 enum object_type type;
223 unsigned long size;
224 char *buf = read_sha1_file(obj->sha1,
225 &type, &size);
226 if (buf) {
227 if (fwrite(buf, size, 1, f) != 1)
228 die("Could not write %s: %s",
229 filename, strerror(errno));
230 free(buf);
231 }
232 } else
233 fprintf(f, "%s\n", sha1_to_hex(obj->sha1));
234 if (fclose(f))
235 die("Could not finish %s: %s",
236 filename, strerror(errno));
237 }
238 return;
239 }
240
241 /*
242 * Otherwise? It's there, it's unreachable, and some other unreachable
243 * object points to it. Ignore it - it's not interesting, and we showed
244 * all the interesting cases above.
245 */
246 }
247
248 static void check_object(struct object *obj)
249 {
250 if (verbose)
251 fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1));
252
253 if (obj->flags & REACHABLE)
254 check_reachable_object(obj);
255 else
256 check_unreachable_object(obj);
257 }
258
259 static void check_connectivity(void)
260 {
261 int i, max;
262
263 /* Traverse the pending reachable objects */
264 traverse_reachable();
265
266 /* Look up all the requirements, warn about missing objects.. */
267 max = get_max_object_index();
268 if (verbose)
269 fprintf(stderr, "Checking connectivity (%d objects)\n", max);
270
271 for (i = 0; i < max; i++) {
272 struct object *obj = get_indexed_object(i);
273
274 if (obj)
275 check_object(obj);
276 }
277 }
278
279 static int fsck_sha1(const unsigned char *sha1)
280 {
281 struct object *obj = parse_object(sha1);
282 if (!obj) {
283 errors_found |= ERROR_OBJECT;
284 return error("%s: object corrupt or missing",
285 sha1_to_hex(sha1));
286 }
287 if (obj->flags & SEEN)
288 return 0;
289 obj->flags |= SEEN;
290
291 if (verbose)
292 fprintf(stderr, "Checking %s %s\n",
293 typename(obj->type), sha1_to_hex(obj->sha1));
294
295 if (fsck_walk(obj, mark_used, 0))
296 objerror(obj, "broken links");
297 if (fsck_object(obj, check_strict, fsck_error_func))
298 return -1;
299
300 if (obj->type == OBJ_TREE) {
301 struct tree *item = (struct tree *) obj;
302
303 free(item->buffer);
304 item->buffer = NULL;
305 }
306
307 if (obj->type == OBJ_COMMIT) {
308 struct commit *commit = (struct commit *) obj;
309
310 free(commit->buffer);
311 commit->buffer = NULL;
312
313 if (!commit->parents && show_root)
314 printf("root %s\n", sha1_to_hex(commit->object.sha1));
315 }
316
317 if (obj->type == OBJ_TAG) {
318 struct tag *tag = (struct tag *) obj;
319
320 if (show_tags && tag->tagged) {
321 printf("tagged %s %s", typename(tag->tagged->type), sha1_to_hex(tag->tagged->sha1));
322 printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
323 }
324 }
325
326 return 0;
327 }
328
329 /*
330 * This is the sorting chunk size: make it reasonably
331 * big so that we can sort well..
332 */
333 #define MAX_SHA1_ENTRIES (1024)
334
335 struct sha1_entry {
336 unsigned long ino;
337 unsigned char sha1[20];
338 };
339
340 static struct {
341 unsigned long nr;
342 struct sha1_entry *entry[MAX_SHA1_ENTRIES];
343 } sha1_list;
344
345 static int ino_compare(const void *_a, const void *_b)
346 {
347 const struct sha1_entry *a = _a, *b = _b;
348 unsigned long ino1 = a->ino, ino2 = b->ino;
349 return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
350 }
351
352 static void fsck_sha1_list(void)
353 {
354 int i, nr = sha1_list.nr;
355
356 if (SORT_DIRENT)
357 qsort(sha1_list.entry, nr,
358 sizeof(struct sha1_entry *), ino_compare);
359 for (i = 0; i < nr; i++) {
360 struct sha1_entry *entry = sha1_list.entry[i];
361 unsigned char *sha1 = entry->sha1;
362
363 sha1_list.entry[i] = NULL;
364 fsck_sha1(sha1);
365 free(entry);
366 }
367 sha1_list.nr = 0;
368 }
369
370 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
371 {
372 struct sha1_entry *entry = xmalloc(sizeof(*entry));
373 int nr;
374
375 entry->ino = ino;
376 hashcpy(entry->sha1, sha1);
377 nr = sha1_list.nr;
378 if (nr == MAX_SHA1_ENTRIES) {
379 fsck_sha1_list();
380 nr = 0;
381 }
382 sha1_list.entry[nr] = entry;
383 sha1_list.nr = ++nr;
384 }
385
386 static void fsck_dir(int i, char *path)
387 {
388 DIR *dir = opendir(path);
389 struct dirent *de;
390
391 if (!dir)
392 return;
393
394 if (verbose)
395 fprintf(stderr, "Checking directory %s\n", path);
396
397 while ((de = readdir(dir)) != NULL) {
398 char name[100];
399 unsigned char sha1[20];
400
401 if (is_dot_or_dotdot(de->d_name))
402 continue;
403 if (strlen(de->d_name) == 38) {
404 sprintf(name, "%02x", i);
405 memcpy(name+2, de->d_name, 39);
406 if (get_sha1_hex(name, sha1) < 0)
407 break;
408 add_sha1_list(sha1, DIRENT_SORT_HINT(de));
409 continue;
410 }
411 if (!prefixcmp(de->d_name, "tmp_obj_"))
412 continue;
413 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
414 }
415 closedir(dir);
416 }
417
418 static int default_refs;
419
420 static int fsck_handle_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
421 const char *email, unsigned long timestamp, int tz,
422 const char *message, void *cb_data)
423 {
424 struct object *obj;
425
426 if (verbose)
427 fprintf(stderr, "Checking reflog %s->%s\n",
428 sha1_to_hex(osha1), sha1_to_hex(nsha1));
429
430 if (!is_null_sha1(osha1)) {
431 obj = lookup_object(osha1);
432 if (obj) {
433 obj->used = 1;
434 mark_object_reachable(obj);
435 }
436 }
437 obj = lookup_object(nsha1);
438 if (obj) {
439 obj->used = 1;
440 mark_object_reachable(obj);
441 }
442 return 0;
443 }
444
445 static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, int flag, void *cb_data)
446 {
447 for_each_reflog_ent(logname, fsck_handle_reflog_ent, NULL);
448 return 0;
449 }
450
451 static int is_branch(const char *refname)
452 {
453 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
454 }
455
456 static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
457 {
458 struct object *obj;
459
460 obj = parse_object(sha1);
461 if (!obj) {
462 error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
463 /* We'll continue with the rest despite the error.. */
464 return 0;
465 }
466 if (obj->type != OBJ_COMMIT && is_branch(refname))
467 error("%s: not a commit", refname);
468 default_refs++;
469 obj->used = 1;
470 mark_object_reachable(obj);
471
472 return 0;
473 }
474
475 static void get_default_heads(void)
476 {
477 if (head_points_at && !is_null_sha1(head_sha1))
478 fsck_handle_ref("HEAD", head_sha1, 0, NULL);
479 for_each_ref(fsck_handle_ref, NULL);
480 if (include_reflogs)
481 for_each_reflog(fsck_handle_reflog, NULL);
482
483 /*
484 * Not having any default heads isn't really fatal, but
485 * it does mean that "--unreachable" no longer makes any
486 * sense (since in this case everything will obviously
487 * be unreachable by definition.
488 *
489 * Showing dangling objects is valid, though (as those
490 * dangling objects are likely lost heads).
491 *
492 * So we just print a warning about it, and clear the
493 * "show_unreachable" flag.
494 */
495 if (!default_refs) {
496 fprintf(stderr, "notice: No default references\n");
497 show_unreachable = 0;
498 }
499 }
500
501 static void fsck_object_dir(const char *path)
502 {
503 int i;
504
505 if (verbose)
506 fprintf(stderr, "Checking object directory\n");
507
508 for (i = 0; i < 256; i++) {
509 static char dir[4096];
510 sprintf(dir, "%s/%02x", path, i);
511 fsck_dir(i, dir);
512 }
513 fsck_sha1_list();
514 }
515
516 static int fsck_head_link(void)
517 {
518 int flag;
519 int null_is_error = 0;
520
521 if (verbose)
522 fprintf(stderr, "Checking HEAD link\n");
523
524 head_points_at = resolve_ref("HEAD", head_sha1, 0, &flag);
525 if (!head_points_at)
526 return error("Invalid HEAD");
527 if (!strcmp(head_points_at, "HEAD"))
528 /* detached HEAD */
529 null_is_error = 1;
530 else if (prefixcmp(head_points_at, "refs/heads/"))
531 return error("HEAD points to something strange (%s)",
532 head_points_at);
533 if (is_null_sha1(head_sha1)) {
534 if (null_is_error)
535 return error("HEAD: detached HEAD points at nothing");
536 fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
537 head_points_at + 11);
538 }
539 return 0;
540 }
541
542 static int fsck_cache_tree(struct cache_tree *it)
543 {
544 int i;
545 int err = 0;
546
547 if (verbose)
548 fprintf(stderr, "Checking cache tree\n");
549
550 if (0 <= it->entry_count) {
551 struct object *obj = parse_object(it->sha1);
552 if (!obj) {
553 error("%s: invalid sha1 pointer in cache-tree",
554 sha1_to_hex(it->sha1));
555 return 1;
556 }
557 mark_object_reachable(obj);
558 obj->used = 1;
559 if (obj->type != OBJ_TREE)
560 err |= objerror(obj, "non-tree in cache-tree");
561 }
562 for (i = 0; i < it->subtree_nr; i++)
563 err |= fsck_cache_tree(it->down[i]->cache_tree);
564 return err;
565 }
566
567 static char const * const fsck_usage[] = {
568 "git fsck [options] [<object>...]",
569 NULL
570 };
571
572 static struct option fsck_opts[] = {
573 OPT__VERBOSE(&verbose),
574 OPT_BOOLEAN(0, "unreachable", &show_unreachable, "show unreachable objects"),
575 OPT_BOOLEAN(0, "tags", &show_tags, "report tags"),
576 OPT_BOOLEAN(0, "root", &show_root, "report root nodes"),
577 OPT_BOOLEAN(0, "cache", &keep_cache_objects, "make index objects head nodes"),
578 OPT_BOOLEAN(0, "reflogs", &include_reflogs, "make reflogs head nodes (default)"),
579 OPT_BOOLEAN(0, "full", &check_full, "also consider alternate objects"),
580 OPT_BOOLEAN(0, "strict", &check_strict, "enable more strict checking"),
581 OPT_BOOLEAN(0, "lost-found", &write_lost_and_found,
582 "write dangling objects in .git/lost-found"),
583 OPT_END(),
584 };
585
586 int cmd_fsck(int argc, const char **argv, const char *prefix)
587 {
588 int i, heads;
589 struct alternate_object_database *alt;
590
591 errors_found = 0;
592
593 argc = parse_options(argc, argv, fsck_opts, fsck_usage, 0);
594 if (write_lost_and_found) {
595 check_full = 1;
596 include_reflogs = 0;
597 }
598
599 fsck_head_link();
600 fsck_object_dir(get_object_directory());
601
602 prepare_alt_odb();
603 for (alt = alt_odb_list; alt; alt = alt->next) {
604 char namebuf[PATH_MAX];
605 int namelen = alt->name - alt->base;
606 memcpy(namebuf, alt->base, namelen);
607 namebuf[namelen - 1] = 0;
608 fsck_object_dir(namebuf);
609 }
610
611 if (check_full) {
612 struct packed_git *p;
613
614 prepare_packed_git();
615 for (p = packed_git; p; p = p->next)
616 /* verify gives error messages itself */
617 verify_pack(p);
618
619 for (p = packed_git; p; p = p->next) {
620 uint32_t j, num;
621 if (open_pack_index(p))
622 continue;
623 num = p->num_objects;
624 for (j = 0; j < num; j++)
625 fsck_sha1(nth_packed_object_sha1(p, j));
626 }
627 }
628
629 heads = 0;
630 for (i = 0; i < argc; i++) {
631 const char *arg = argv[i];
632 unsigned char sha1[20];
633 if (!get_sha1(arg, sha1)) {
634 struct object *obj = lookup_object(sha1);
635
636 /* Error is printed by lookup_object(). */
637 if (!obj)
638 continue;
639
640 obj->used = 1;
641 mark_object_reachable(obj);
642 heads++;
643 continue;
644 }
645 error("invalid parameter: expected sha1, got '%s'", arg);
646 }
647
648 /*
649 * If we've not been given any explicit head information, do the
650 * default ones from .git/refs. We also consider the index file
651 * in this case (ie this implies --cache).
652 */
653 if (!heads) {
654 get_default_heads();
655 keep_cache_objects = 1;
656 }
657
658 if (keep_cache_objects) {
659 read_cache();
660 for (i = 0; i < active_nr; i++) {
661 unsigned int mode;
662 struct blob *blob;
663 struct object *obj;
664
665 mode = active_cache[i]->ce_mode;
666 if (S_ISGITLINK(mode))
667 continue;
668 blob = lookup_blob(active_cache[i]->sha1);
669 if (!blob)
670 continue;
671 obj = &blob->object;
672 obj->used = 1;
673 mark_object_reachable(obj);
674 }
675 if (active_cache_tree)
676 fsck_cache_tree(active_cache_tree);
677 }
678
679 check_connectivity();
680 return errors_found;
681 }