Merge branch 'jc/maint-1.6.0-pack-directory' into maint-1.6.1
[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
14 #define REACHABLE 0x0001
15 #define SEEN 0x0002
16
17 static int show_root;
18 static int show_tags;
19 static int show_unreachable;
20 static int include_reflogs = 1;
21 static int check_full;
22 static int check_strict;
23 static int keep_cache_objects;
24 static unsigned char head_sha1[20];
25 static int errors_found;
26 static int write_lost_and_found;
27 static int verbose;
28 #define ERROR_OBJECT 01
29 #define ERROR_REACHABLE 02
30
31 #ifdef NO_D_INO_IN_DIRENT
32 #define SORT_DIRENT 0
33 #define DIRENT_SORT_HINT(de) 0
34 #else
35 #define SORT_DIRENT 1
36 #define DIRENT_SORT_HINT(de) ((de)->d_ino)
37 #endif
38
39 static void objreport(struct object *obj, const char *severity,
40 const char *err, va_list params)
41 {
42 fprintf(stderr, "%s in %s %s: ",
43 severity, typename(obj->type), sha1_to_hex(obj->sha1));
44 vfprintf(stderr, err, params);
45 fputs("\n", stderr);
46 }
47
48 static int objerror(struct object *obj, const char *err, ...)
49 {
50 va_list params;
51 va_start(params, err);
52 errors_found |= ERROR_OBJECT;
53 objreport(obj, "error", err, params);
54 va_end(params);
55 return -1;
56 }
57
58 static int fsck_error_func(struct object *obj, int type, const char *err, ...)
59 {
60 va_list params;
61 va_start(params, err);
62 objreport(obj, (type == FSCK_WARN) ? "warning" : "error", err, params);
63 va_end(params);
64 return (type == FSCK_WARN) ? 0 : 1;
65 }
66
67 static struct object_array pending;
68
69 static int mark_object(struct object *obj, int type, void *data)
70 {
71 struct object *parent = data;
72
73 if (!obj) {
74 printf("broken link from %7s %s\n",
75 typename(parent->type), sha1_to_hex(parent->sha1));
76 printf("broken link from %7s %s\n",
77 (type == OBJ_ANY ? "unknown" : typename(type)), "unknown");
78 errors_found |= ERROR_REACHABLE;
79 return 1;
80 }
81
82 if (type != OBJ_ANY && obj->type != type)
83 objerror(parent, "wrong object type in link");
84
85 if (obj->flags & REACHABLE)
86 return 0;
87 obj->flags |= REACHABLE;
88 if (!obj->parsed) {
89 if (parent && !has_sha1_file(obj->sha1)) {
90 printf("broken link from %7s %s\n",
91 typename(parent->type), sha1_to_hex(parent->sha1));
92 printf(" to %7s %s\n",
93 typename(obj->type), sha1_to_hex(obj->sha1));
94 errors_found |= ERROR_REACHABLE;
95 }
96 return 1;
97 }
98
99 add_object_array(obj, (void *) parent, &pending);
100 return 0;
101 }
102
103 static void mark_object_reachable(struct object *obj)
104 {
105 mark_object(obj, OBJ_ANY, 0);
106 }
107
108 static int traverse_one_object(struct object *obj, struct object *parent)
109 {
110 int result;
111 struct tree *tree = NULL;
112
113 if (obj->type == OBJ_TREE) {
114 obj->parsed = 0;
115 tree = (struct tree *)obj;
116 if (parse_tree(tree) < 0)
117 return 1; /* error already displayed */
118 }
119 result = fsck_walk(obj, mark_object, obj);
120 if (tree) {
121 free(tree->buffer);
122 tree->buffer = NULL;
123 }
124 return result;
125 }
126
127 static int traverse_reachable(void)
128 {
129 int result = 0;
130 while (pending.nr) {
131 struct object_array_entry *entry;
132 struct object *obj, *parent;
133
134 entry = pending.objects + --pending.nr;
135 obj = entry->item;
136 parent = (struct object *) entry->name;
137 result |= traverse_one_object(obj, parent);
138 }
139 return !!result;
140 }
141
142 static int mark_used(struct object *obj, int type, void *data)
143 {
144 if (!obj)
145 return 1;
146 obj->used = 1;
147 return 0;
148 }
149
150 /*
151 * Check a single reachable object
152 */
153 static void check_reachable_object(struct object *obj)
154 {
155 /*
156 * We obviously want the object to be parsed,
157 * except if it was in a pack-file and we didn't
158 * do a full fsck
159 */
160 if (!obj->parsed) {
161 if (has_sha1_pack(obj->sha1, NULL))
162 return; /* it is in pack - forget about it */
163 printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
164 errors_found |= ERROR_REACHABLE;
165 return;
166 }
167 }
168
169 /*
170 * Check a single unreachable object
171 */
172 static void check_unreachable_object(struct object *obj)
173 {
174 /*
175 * Missing unreachable object? Ignore it. It's not like
176 * we miss it (since it can't be reached), nor do we want
177 * to complain about it being unreachable (since it does
178 * not exist).
179 */
180 if (!obj->parsed)
181 return;
182
183 /*
184 * Unreachable object that exists? Show it if asked to,
185 * since this is something that is prunable.
186 */
187 if (show_unreachable) {
188 printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1));
189 return;
190 }
191
192 /*
193 * "!used" means that nothing at all points to it, including
194 * other unreachable objects. In other words, it's the "tip"
195 * of some set of unreachable objects, usually a commit that
196 * got dropped.
197 *
198 * Such starting points are more interesting than some random
199 * set of unreachable objects, so we show them even if the user
200 * hasn't asked for _all_ unreachable objects. If you have
201 * deleted a branch by mistake, this is a prime candidate to
202 * start looking at, for example.
203 */
204 if (!obj->used) {
205 printf("dangling %s %s\n", typename(obj->type),
206 sha1_to_hex(obj->sha1));
207 if (write_lost_and_found) {
208 char *filename = git_path("lost-found/%s/%s",
209 obj->type == OBJ_COMMIT ? "commit" : "other",
210 sha1_to_hex(obj->sha1));
211 FILE *f;
212
213 if (safe_create_leading_directories(filename)) {
214 error("Could not create lost-found");
215 return;
216 }
217 if (!(f = fopen(filename, "w")))
218 die("Could not open %s", filename);
219 if (obj->type == OBJ_BLOB) {
220 enum object_type type;
221 unsigned long size;
222 char *buf = read_sha1_file(obj->sha1,
223 &type, &size);
224 if (buf) {
225 if (fwrite(buf, size, 1, f) != 1)
226 die("Could not write %s: %s",
227 filename, strerror(errno));
228 free(buf);
229 }
230 } else
231 fprintf(f, "%s\n", sha1_to_hex(obj->sha1));
232 if (fclose(f))
233 die("Could not finish %s: %s",
234 filename, strerror(errno));
235 }
236 return;
237 }
238
239 /*
240 * Otherwise? It's there, it's unreachable, and some other unreachable
241 * object points to it. Ignore it - it's not interesting, and we showed
242 * all the interesting cases above.
243 */
244 }
245
246 static void check_object(struct object *obj)
247 {
248 if (verbose)
249 fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1));
250
251 if (obj->flags & REACHABLE)
252 check_reachable_object(obj);
253 else
254 check_unreachable_object(obj);
255 }
256
257 static void check_connectivity(void)
258 {
259 int i, max;
260
261 /* Traverse the pending reachable objects */
262 traverse_reachable();
263
264 /* Look up all the requirements, warn about missing objects.. */
265 max = get_max_object_index();
266 if (verbose)
267 fprintf(stderr, "Checking connectivity (%d objects)\n", max);
268
269 for (i = 0; i < max; i++) {
270 struct object *obj = get_indexed_object(i);
271
272 if (obj)
273 check_object(obj);
274 }
275 }
276
277 static int fsck_sha1(const unsigned char *sha1)
278 {
279 struct object *obj = parse_object(sha1);
280 if (!obj) {
281 errors_found |= ERROR_OBJECT;
282 return error("%s: object corrupt or missing",
283 sha1_to_hex(sha1));
284 }
285 if (obj->flags & SEEN)
286 return 0;
287 obj->flags |= SEEN;
288
289 if (verbose)
290 fprintf(stderr, "Checking %s %s\n",
291 typename(obj->type), sha1_to_hex(obj->sha1));
292
293 if (fsck_walk(obj, mark_used, 0))
294 objerror(obj, "broken links");
295 if (fsck_object(obj, check_strict, fsck_error_func))
296 return -1;
297
298 if (obj->type == OBJ_TREE) {
299 struct tree *item = (struct tree *) obj;
300
301 free(item->buffer);
302 item->buffer = NULL;
303 }
304
305 if (obj->type == OBJ_COMMIT) {
306 struct commit *commit = (struct commit *) obj;
307
308 free(commit->buffer);
309 commit->buffer = NULL;
310
311 if (!commit->parents && show_root)
312 printf("root %s\n", sha1_to_hex(commit->object.sha1));
313 }
314
315 if (obj->type == OBJ_TAG) {
316 struct tag *tag = (struct tag *) obj;
317
318 if (show_tags && tag->tagged) {
319 printf("tagged %s %s", typename(tag->tagged->type), sha1_to_hex(tag->tagged->sha1));
320 printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1));
321 }
322 }
323
324 return 0;
325 }
326
327 /*
328 * This is the sorting chunk size: make it reasonably
329 * big so that we can sort well..
330 */
331 #define MAX_SHA1_ENTRIES (1024)
332
333 struct sha1_entry {
334 unsigned long ino;
335 unsigned char sha1[20];
336 };
337
338 static struct {
339 unsigned long nr;
340 struct sha1_entry *entry[MAX_SHA1_ENTRIES];
341 } sha1_list;
342
343 static int ino_compare(const void *_a, const void *_b)
344 {
345 const struct sha1_entry *a = _a, *b = _b;
346 unsigned long ino1 = a->ino, ino2 = b->ino;
347 return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0;
348 }
349
350 static void fsck_sha1_list(void)
351 {
352 int i, nr = sha1_list.nr;
353
354 if (SORT_DIRENT)
355 qsort(sha1_list.entry, nr,
356 sizeof(struct sha1_entry *), ino_compare);
357 for (i = 0; i < nr; i++) {
358 struct sha1_entry *entry = sha1_list.entry[i];
359 unsigned char *sha1 = entry->sha1;
360
361 sha1_list.entry[i] = NULL;
362 fsck_sha1(sha1);
363 free(entry);
364 }
365 sha1_list.nr = 0;
366 }
367
368 static void add_sha1_list(unsigned char *sha1, unsigned long ino)
369 {
370 struct sha1_entry *entry = xmalloc(sizeof(*entry));
371 int nr;
372
373 entry->ino = ino;
374 hashcpy(entry->sha1, sha1);
375 nr = sha1_list.nr;
376 if (nr == MAX_SHA1_ENTRIES) {
377 fsck_sha1_list();
378 nr = 0;
379 }
380 sha1_list.entry[nr] = entry;
381 sha1_list.nr = ++nr;
382 }
383
384 static void fsck_dir(int i, char *path)
385 {
386 DIR *dir = opendir(path);
387 struct dirent *de;
388
389 if (!dir)
390 return;
391
392 if (verbose)
393 fprintf(stderr, "Checking directory %s\n", path);
394
395 while ((de = readdir(dir)) != NULL) {
396 char name[100];
397 unsigned char sha1[20];
398 int len = strlen(de->d_name);
399
400 switch (len) {
401 case 2:
402 if (de->d_name[1] != '.')
403 break;
404 case 1:
405 if (de->d_name[0] != '.')
406 break;
407 continue;
408 case 38:
409 sprintf(name, "%02x", i);
410 memcpy(name+2, de->d_name, len+1);
411 if (get_sha1_hex(name, sha1) < 0)
412 break;
413 add_sha1_list(sha1, DIRENT_SORT_HINT(de));
414 continue;
415 }
416 if (!prefixcmp(de->d_name, "tmp_obj_"))
417 continue;
418 fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name);
419 }
420 closedir(dir);
421 }
422
423 static int default_refs;
424
425 static int fsck_handle_reflog_ent(unsigned char *osha1, unsigned char *nsha1,
426 const char *email, unsigned long timestamp, int tz,
427 const char *message, void *cb_data)
428 {
429 struct object *obj;
430
431 if (verbose)
432 fprintf(stderr, "Checking reflog %s->%s\n",
433 sha1_to_hex(osha1), sha1_to_hex(nsha1));
434
435 if (!is_null_sha1(osha1)) {
436 obj = lookup_object(osha1);
437 if (obj) {
438 obj->used = 1;
439 mark_object_reachable(obj);
440 }
441 }
442 obj = lookup_object(nsha1);
443 if (obj) {
444 obj->used = 1;
445 mark_object_reachable(obj);
446 }
447 return 0;
448 }
449
450 static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, int flag, void *cb_data)
451 {
452 for_each_reflog_ent(logname, fsck_handle_reflog_ent, NULL);
453 return 0;
454 }
455
456 static int is_branch(const char *refname)
457 {
458 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
459 }
460
461 static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data)
462 {
463 struct object *obj;
464
465 obj = parse_object(sha1);
466 if (!obj) {
467 error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1));
468 /* We'll continue with the rest despite the error.. */
469 return 0;
470 }
471 if (obj->type != OBJ_COMMIT && is_branch(refname))
472 error("%s: not a commit", refname);
473 default_refs++;
474 obj->used = 1;
475 mark_object_reachable(obj);
476
477 return 0;
478 }
479
480 static void get_default_heads(void)
481 {
482 for_each_ref(fsck_handle_ref, NULL);
483 if (include_reflogs)
484 for_each_reflog(fsck_handle_reflog, NULL);
485
486 /*
487 * Not having any default heads isn't really fatal, but
488 * it does mean that "--unreachable" no longer makes any
489 * sense (since in this case everything will obviously
490 * be unreachable by definition.
491 *
492 * Showing dangling objects is valid, though (as those
493 * dangling objects are likely lost heads).
494 *
495 * So we just print a warning about it, and clear the
496 * "show_unreachable" flag.
497 */
498 if (!default_refs) {
499 fprintf(stderr, "notice: No default references\n");
500 show_unreachable = 0;
501 }
502 }
503
504 static void fsck_object_dir(const char *path)
505 {
506 int i;
507
508 if (verbose)
509 fprintf(stderr, "Checking object directory\n");
510
511 for (i = 0; i < 256; i++) {
512 static char dir[4096];
513 sprintf(dir, "%s/%02x", path, i);
514 fsck_dir(i, dir);
515 }
516 fsck_sha1_list();
517 }
518
519 static int fsck_head_link(void)
520 {
521 unsigned char sha1[20];
522 int flag;
523 int null_is_error = 0;
524 const char *head_points_at = resolve_ref("HEAD", sha1, 0, &flag);
525
526 if (verbose)
527 fprintf(stderr, "Checking HEAD link\n");
528
529 if (!head_points_at)
530 return error("Invalid HEAD");
531 if (!strcmp(head_points_at, "HEAD"))
532 /* detached HEAD */
533 null_is_error = 1;
534 else if (prefixcmp(head_points_at, "refs/heads/"))
535 return error("HEAD points to something strange (%s)",
536 head_points_at);
537 if (is_null_sha1(sha1)) {
538 if (null_is_error)
539 return error("HEAD: detached HEAD points at nothing");
540 fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
541 head_points_at + 11);
542 }
543 return 0;
544 }
545
546 static int fsck_cache_tree(struct cache_tree *it)
547 {
548 int i;
549 int err = 0;
550
551 if (verbose)
552 fprintf(stderr, "Checking cache tree\n");
553
554 if (0 <= it->entry_count) {
555 struct object *obj = parse_object(it->sha1);
556 if (!obj) {
557 error("%s: invalid sha1 pointer in cache-tree",
558 sha1_to_hex(it->sha1));
559 return 1;
560 }
561 mark_object_reachable(obj);
562 obj->used = 1;
563 if (obj->type != OBJ_TREE)
564 err |= objerror(obj, "non-tree in cache-tree");
565 }
566 for (i = 0; i < it->subtree_nr; i++)
567 err |= fsck_cache_tree(it->down[i]->cache_tree);
568 return err;
569 }
570
571 static char const * const fsck_usage[] = {
572 "git fsck [options] [<object>...]",
573 NULL
574 };
575
576 static struct option fsck_opts[] = {
577 OPT__VERBOSE(&verbose),
578 OPT_BOOLEAN(0, "unreachable", &show_unreachable, "show unreachable objects"),
579 OPT_BOOLEAN(0, "tags", &show_tags, "report tags"),
580 OPT_BOOLEAN(0, "root", &show_root, "report root nodes"),
581 OPT_BOOLEAN(0, "cache", &keep_cache_objects, "make index objects head nodes"),
582 OPT_BOOLEAN(0, "reflogs", &include_reflogs, "make reflogs head nodes (default)"),
583 OPT_BOOLEAN(0, "full", &check_full, "also consider alternate objects"),
584 OPT_BOOLEAN(0, "strict", &check_strict, "enable more strict checking"),
585 OPT_BOOLEAN(0, "lost-found", &write_lost_and_found,
586 "write dangling objects in .git/lost-found"),
587 OPT_END(),
588 };
589
590 int cmd_fsck(int argc, const char **argv, const char *prefix)
591 {
592 int i, heads;
593
594 errors_found = 0;
595
596 argc = parse_options(argc, argv, fsck_opts, fsck_usage, 0);
597 if (write_lost_and_found) {
598 check_full = 1;
599 include_reflogs = 0;
600 }
601
602 fsck_head_link();
603 fsck_object_dir(get_object_directory());
604 if (check_full) {
605 struct alternate_object_database *alt;
606 struct packed_git *p;
607 prepare_alt_odb();
608 for (alt = alt_odb_list; alt; alt = alt->next) {
609 char namebuf[PATH_MAX];
610 int namelen = alt->name - alt->base;
611 memcpy(namebuf, alt->base, namelen);
612 namebuf[namelen - 1] = 0;
613 fsck_object_dir(namebuf);
614 }
615 prepare_packed_git();
616 for (p = packed_git; p; p = p->next)
617 /* verify gives error messages itself */
618 verify_pack(p);
619
620 for (p = packed_git; p; p = p->next) {
621 uint32_t j, num;
622 if (open_pack_index(p))
623 continue;
624 num = p->num_objects;
625 for (j = 0; j < num; j++)
626 fsck_sha1(nth_packed_object_sha1(p, j));
627 }
628 }
629
630 heads = 0;
631 for (i = 0; i < argc; i++) {
632 const char *arg = argv[i];
633 if (!get_sha1(arg, head_sha1)) {
634 struct object *obj = lookup_object(head_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 }