Merge branch 'rd/doc-options-placeholder'
[git] / builtin / fsck.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "repository.h"
4 #include "config.h"
5 #include "commit.h"
6 #include "tree.h"
7 #include "blob.h"
8 #include "tag.h"
9 #include "refs.h"
10 #include "pack.h"
11 #include "cache-tree.h"
12 #include "tree-walk.h"
13 #include "fsck.h"
14 #include "parse-options.h"
15 #include "dir.h"
16 #include "progress.h"
17 #include "streaming.h"
18 #include "decorate.h"
19 #include "packfile.h"
20 #include "object-store.h"
21
22 #define REACHABLE 0x0001
23 #define SEEN      0x0002
24 #define HAS_OBJ   0x0004
25 /* This flag is set if something points to this object. */
26 #define USED      0x0008
27
28 static int show_root;
29 static int show_tags;
30 static int show_unreachable;
31 static int include_reflogs = 1;
32 static int check_full = 1;
33 static int connectivity_only;
34 static int check_strict;
35 static int keep_cache_objects;
36 static struct fsck_options fsck_walk_options = FSCK_OPTIONS_DEFAULT;
37 static struct fsck_options fsck_obj_options = FSCK_OPTIONS_DEFAULT;
38 static struct object_id head_oid;
39 static const char *head_points_at;
40 static int errors_found;
41 static int write_lost_and_found;
42 static int verbose;
43 static int show_progress = -1;
44 static int show_dangling = 1;
45 static int name_objects;
46 #define ERROR_OBJECT 01
47 #define ERROR_REACHABLE 02
48 #define ERROR_PACK 04
49 #define ERROR_REFS 010
50
51 static const char *describe_object(struct object *obj)
52 {
53         static struct strbuf buf = STRBUF_INIT;
54         char *name = name_objects ?
55                 lookup_decoration(fsck_walk_options.object_names, obj) : NULL;
56
57         strbuf_reset(&buf);
58         strbuf_addstr(&buf, oid_to_hex(&obj->oid));
59         if (name)
60                 strbuf_addf(&buf, " (%s)", name);
61
62         return buf.buf;
63 }
64
65 static const char *printable_type(struct object *obj)
66 {
67         const char *ret;
68
69         if (obj->type == OBJ_NONE) {
70                 enum object_type type = oid_object_info(the_repository,
71                                                         &obj->oid, NULL);
72                 if (type > 0)
73                         object_as_type(obj, type, 0);
74         }
75
76         ret = type_name(obj->type);
77         if (!ret)
78                 ret = "unknown";
79
80         return ret;
81 }
82
83 static int fsck_config(const char *var, const char *value, void *cb)
84 {
85         if (strcmp(var, "fsck.skiplist") == 0) {
86                 const char *path;
87                 struct strbuf sb = STRBUF_INIT;
88
89                 if (git_config_pathname(&path, var, value))
90                         return 1;
91                 strbuf_addf(&sb, "skiplist=%s", path);
92                 free((char *)path);
93                 fsck_set_msg_types(&fsck_obj_options, sb.buf);
94                 strbuf_release(&sb);
95                 return 0;
96         }
97
98         if (skip_prefix(var, "fsck.", &var)) {
99                 fsck_set_msg_type(&fsck_obj_options, var, value);
100                 return 0;
101         }
102
103         return git_default_config(var, value, cb);
104 }
105
106 static void objreport(struct object *obj, const char *msg_type,
107                         const char *err)
108 {
109         fprintf(stderr, "%s in %s %s: %s\n",
110                 msg_type, printable_type(obj), describe_object(obj), err);
111 }
112
113 static int objerror(struct object *obj, const char *err)
114 {
115         errors_found |= ERROR_OBJECT;
116         objreport(obj, "error", err);
117         return -1;
118 }
119
120 static int fsck_error_func(struct fsck_options *o,
121         struct object *obj, int type, const char *message)
122 {
123         objreport(obj, (type == FSCK_WARN) ? "warning" : "error", message);
124         return (type == FSCK_WARN) ? 0 : 1;
125 }
126
127 static struct object_array pending;
128
129 static int mark_object(struct object *obj, int type, void *data, struct fsck_options *options)
130 {
131         struct object *parent = data;
132
133         /*
134          * The only case data is NULL or type is OBJ_ANY is when
135          * mark_object_reachable() calls us.  All the callers of
136          * that function has non-NULL obj hence ...
137          */
138         if (!obj) {
139                 /* ... these references to parent->fld are safe here */
140                 printf("broken link from %7s %s\n",
141                            printable_type(parent), describe_object(parent));
142                 printf("broken link from %7s %s\n",
143                            (type == OBJ_ANY ? "unknown" : type_name(type)), "unknown");
144                 errors_found |= ERROR_REACHABLE;
145                 return 1;
146         }
147
148         if (type != OBJ_ANY && obj->type != type)
149                 /* ... and the reference to parent is safe here */
150                 objerror(parent, "wrong object type in link");
151
152         if (obj->flags & REACHABLE)
153                 return 0;
154         obj->flags |= REACHABLE;
155
156         if (is_promisor_object(&obj->oid))
157                 /*
158                  * Further recursion does not need to be performed on this
159                  * object since it is a promisor object (so it does not need to
160                  * be added to "pending").
161                  */
162                 return 0;
163
164         if (!(obj->flags & HAS_OBJ)) {
165                 if (parent && !has_object_file(&obj->oid)) {
166                         printf("broken link from %7s %s\n",
167                                  printable_type(parent), describe_object(parent));
168                         printf("              to %7s %s\n",
169                                  printable_type(obj), describe_object(obj));
170                         errors_found |= ERROR_REACHABLE;
171                 }
172                 return 1;
173         }
174
175         add_object_array(obj, NULL, &pending);
176         return 0;
177 }
178
179 static void mark_object_reachable(struct object *obj)
180 {
181         mark_object(obj, OBJ_ANY, NULL, NULL);
182 }
183
184 static int traverse_one_object(struct object *obj)
185 {
186         int result = fsck_walk(obj, obj, &fsck_walk_options);
187
188         if (obj->type == OBJ_TREE) {
189                 struct tree *tree = (struct tree *)obj;
190                 free_tree_buffer(tree);
191         }
192         return result;
193 }
194
195 static int traverse_reachable(void)
196 {
197         struct progress *progress = NULL;
198         unsigned int nr = 0;
199         int result = 0;
200         if (show_progress)
201                 progress = start_delayed_progress(_("Checking connectivity"), 0);
202         while (pending.nr) {
203                 result |= traverse_one_object(object_array_pop(&pending));
204                 display_progress(progress, ++nr);
205         }
206         stop_progress(&progress);
207         return !!result;
208 }
209
210 static int mark_used(struct object *obj, int type, void *data, struct fsck_options *options)
211 {
212         if (!obj)
213                 return 1;
214         obj->flags |= USED;
215         return 0;
216 }
217
218 /*
219  * Check a single reachable object
220  */
221 static void check_reachable_object(struct object *obj)
222 {
223         /*
224          * We obviously want the object to be parsed,
225          * except if it was in a pack-file and we didn't
226          * do a full fsck
227          */
228         if (!(obj->flags & HAS_OBJ)) {
229                 if (is_promisor_object(&obj->oid))
230                         return;
231                 if (has_object_pack(&obj->oid))
232                         return; /* it is in pack - forget about it */
233                 printf("missing %s %s\n", printable_type(obj),
234                         describe_object(obj));
235                 errors_found |= ERROR_REACHABLE;
236                 return;
237         }
238 }
239
240 /*
241  * Check a single unreachable object
242  */
243 static void check_unreachable_object(struct object *obj)
244 {
245         /*
246          * Missing unreachable object? Ignore it. It's not like
247          * we miss it (since it can't be reached), nor do we want
248          * to complain about it being unreachable (since it does
249          * not exist).
250          */
251         if (!(obj->flags & HAS_OBJ))
252                 return;
253
254         /*
255          * Unreachable object that exists? Show it if asked to,
256          * since this is something that is prunable.
257          */
258         if (show_unreachable) {
259                 printf("unreachable %s %s\n", printable_type(obj),
260                         describe_object(obj));
261                 return;
262         }
263
264         /*
265          * "!USED" means that nothing at all points to it, including
266          * other unreachable objects. In other words, it's the "tip"
267          * of some set of unreachable objects, usually a commit that
268          * got dropped.
269          *
270          * Such starting points are more interesting than some random
271          * set of unreachable objects, so we show them even if the user
272          * hasn't asked for _all_ unreachable objects. If you have
273          * deleted a branch by mistake, this is a prime candidate to
274          * start looking at, for example.
275          */
276         if (!(obj->flags & USED)) {
277                 if (show_dangling)
278                         printf("dangling %s %s\n", printable_type(obj),
279                                describe_object(obj));
280                 if (write_lost_and_found) {
281                         char *filename = git_pathdup("lost-found/%s/%s",
282                                 obj->type == OBJ_COMMIT ? "commit" : "other",
283                                 describe_object(obj));
284                         FILE *f;
285
286                         if (safe_create_leading_directories_const(filename)) {
287                                 error("Could not create lost-found");
288                                 free(filename);
289                                 return;
290                         }
291                         f = xfopen(filename, "w");
292                         if (obj->type == OBJ_BLOB) {
293                                 if (stream_blob_to_fd(fileno(f), &obj->oid, NULL, 1))
294                                         die_errno("Could not write '%s'", filename);
295                         } else
296                                 fprintf(f, "%s\n", describe_object(obj));
297                         if (fclose(f))
298                                 die_errno("Could not finish '%s'",
299                                           filename);
300                         free(filename);
301                 }
302                 return;
303         }
304
305         /*
306          * Otherwise? It's there, it's unreachable, and some other unreachable
307          * object points to it. Ignore it - it's not interesting, and we showed
308          * all the interesting cases above.
309          */
310 }
311
312 static void check_object(struct object *obj)
313 {
314         if (verbose)
315                 fprintf(stderr, "Checking %s\n", describe_object(obj));
316
317         if (obj->flags & REACHABLE)
318                 check_reachable_object(obj);
319         else
320                 check_unreachable_object(obj);
321 }
322
323 static void check_connectivity(void)
324 {
325         int i, max;
326
327         /* Traverse the pending reachable objects */
328         traverse_reachable();
329
330         /* Look up all the requirements, warn about missing objects.. */
331         max = get_max_object_index();
332         if (verbose)
333                 fprintf(stderr, "Checking connectivity (%d objects)\n", max);
334
335         for (i = 0; i < max; i++) {
336                 struct object *obj = get_indexed_object(i);
337
338                 if (obj)
339                         check_object(obj);
340         }
341 }
342
343 static int fsck_obj(struct object *obj, void *buffer, unsigned long size)
344 {
345         int err;
346
347         if (obj->flags & SEEN)
348                 return 0;
349         obj->flags |= SEEN;
350
351         if (verbose)
352                 fprintf(stderr, "Checking %s %s\n",
353                         printable_type(obj), describe_object(obj));
354
355         if (fsck_walk(obj, NULL, &fsck_obj_options))
356                 objerror(obj, "broken links");
357         err = fsck_object(obj, buffer, size, &fsck_obj_options);
358         if (err)
359                 goto out;
360
361         if (obj->type == OBJ_COMMIT) {
362                 struct commit *commit = (struct commit *) obj;
363
364                 if (!commit->parents && show_root)
365                         printf("root %s\n", describe_object(&commit->object));
366         }
367
368         if (obj->type == OBJ_TAG) {
369                 struct tag *tag = (struct tag *) obj;
370
371                 if (show_tags && tag->tagged) {
372                         printf("tagged %s %s", printable_type(tag->tagged),
373                                 describe_object(tag->tagged));
374                         printf(" (%s) in %s\n", tag->tag,
375                                 describe_object(&tag->object));
376                 }
377         }
378
379 out:
380         if (obj->type == OBJ_TREE)
381                 free_tree_buffer((struct tree *)obj);
382         if (obj->type == OBJ_COMMIT)
383                 free_commit_buffer((struct commit *)obj);
384         return err;
385 }
386
387 static int fsck_obj_buffer(const struct object_id *oid, enum object_type type,
388                            unsigned long size, void *buffer, int *eaten)
389 {
390         /*
391          * Note, buffer may be NULL if type is OBJ_BLOB. See
392          * verify_packfile(), data_valid variable for details.
393          */
394         struct object *obj;
395         obj = parse_object_buffer(oid, type, size, buffer, eaten);
396         if (!obj) {
397                 errors_found |= ERROR_OBJECT;
398                 return error("%s: object corrupt or missing", oid_to_hex(oid));
399         }
400         obj->flags &= ~(REACHABLE | SEEN);
401         obj->flags |= HAS_OBJ;
402         return fsck_obj(obj, buffer, size);
403 }
404
405 static int default_refs;
406
407 static void fsck_handle_reflog_oid(const char *refname, struct object_id *oid,
408         timestamp_t timestamp)
409 {
410         struct object *obj;
411
412         if (!is_null_oid(oid)) {
413                 obj = lookup_object(oid->hash);
414                 if (obj && (obj->flags & HAS_OBJ)) {
415                         if (timestamp && name_objects)
416                                 add_decoration(fsck_walk_options.object_names,
417                                         obj,
418                                         xstrfmt("%s@{%"PRItime"}", refname, timestamp));
419                         obj->flags |= USED;
420                         mark_object_reachable(obj);
421                 } else if (!is_promisor_object(oid)) {
422                         error("%s: invalid reflog entry %s", refname, oid_to_hex(oid));
423                         errors_found |= ERROR_REACHABLE;
424                 }
425         }
426 }
427
428 static int fsck_handle_reflog_ent(struct object_id *ooid, struct object_id *noid,
429                 const char *email, timestamp_t timestamp, int tz,
430                 const char *message, void *cb_data)
431 {
432         const char *refname = cb_data;
433
434         if (verbose)
435                 fprintf(stderr, "Checking reflog %s->%s\n",
436                         oid_to_hex(ooid), oid_to_hex(noid));
437
438         fsck_handle_reflog_oid(refname, ooid, 0);
439         fsck_handle_reflog_oid(refname, noid, timestamp);
440         return 0;
441 }
442
443 static int fsck_handle_reflog(const char *logname, const struct object_id *oid,
444                               int flag, void *cb_data)
445 {
446         for_each_reflog_ent(logname, fsck_handle_reflog_ent, (void *)logname);
447         return 0;
448 }
449
450 static int fsck_handle_ref(const char *refname, const struct object_id *oid,
451                            int flag, void *cb_data)
452 {
453         struct object *obj;
454
455         obj = parse_object(oid);
456         if (!obj) {
457                 if (is_promisor_object(oid)) {
458                         /*
459                          * Increment default_refs anyway, because this is a
460                          * valid ref.
461                          */
462                          default_refs++;
463                          return 0;
464                 }
465                 error("%s: invalid sha1 pointer %s", refname, oid_to_hex(oid));
466                 errors_found |= ERROR_REACHABLE;
467                 /* We'll continue with the rest despite the error.. */
468                 return 0;
469         }
470         if (obj->type != OBJ_COMMIT && is_branch(refname)) {
471                 error("%s: not a commit", refname);
472                 errors_found |= ERROR_REFS;
473         }
474         default_refs++;
475         obj->flags |= USED;
476         if (name_objects)
477                 add_decoration(fsck_walk_options.object_names,
478                         obj, xstrdup(refname));
479         mark_object_reachable(obj);
480
481         return 0;
482 }
483
484 static void get_default_heads(void)
485 {
486         if (head_points_at && !is_null_oid(&head_oid))
487                 fsck_handle_ref("HEAD", &head_oid, 0, NULL);
488         for_each_rawref(fsck_handle_ref, NULL);
489         if (include_reflogs)
490                 for_each_reflog(fsck_handle_reflog, NULL);
491
492         /*
493          * Not having any default heads isn't really fatal, but
494          * it does mean that "--unreachable" no longer makes any
495          * sense (since in this case everything will obviously
496          * be unreachable by definition.
497          *
498          * Showing dangling objects is valid, though (as those
499          * dangling objects are likely lost heads).
500          *
501          * So we just print a warning about it, and clear the
502          * "show_unreachable" flag.
503          */
504         if (!default_refs) {
505                 fprintf(stderr, "notice: No default references\n");
506                 show_unreachable = 0;
507         }
508 }
509
510 static int fsck_loose(const struct object_id *oid, const char *path, void *data)
511 {
512         struct object *obj;
513         enum object_type type;
514         unsigned long size;
515         void *contents;
516         int eaten;
517
518         if (read_loose_object(path, oid, &type, &size, &contents) < 0) {
519                 errors_found |= ERROR_OBJECT;
520                 error("%s: object corrupt or missing: %s",
521                       oid_to_hex(oid), path);
522                 return 0; /* keep checking other objects */
523         }
524
525         if (!contents && type != OBJ_BLOB)
526                 BUG("read_loose_object streamed a non-blob");
527
528         obj = parse_object_buffer(oid, type, size, contents, &eaten);
529         if (!obj) {
530                 errors_found |= ERROR_OBJECT;
531                 error("%s: object could not be parsed: %s",
532                       oid_to_hex(oid), path);
533                 if (!eaten)
534                         free(contents);
535                 return 0; /* keep checking other objects */
536         }
537
538         obj->flags &= ~(REACHABLE | SEEN);
539         obj->flags |= HAS_OBJ;
540         if (fsck_obj(obj, contents, size))
541                 errors_found |= ERROR_OBJECT;
542
543         if (!eaten)
544                 free(contents);
545         return 0; /* keep checking other objects, even if we saw an error */
546 }
547
548 static int fsck_cruft(const char *basename, const char *path, void *data)
549 {
550         if (!starts_with(basename, "tmp_obj_"))
551                 fprintf(stderr, "bad sha1 file: %s\n", path);
552         return 0;
553 }
554
555 static int fsck_subdir(unsigned int nr, const char *path, void *progress)
556 {
557         display_progress(progress, nr + 1);
558         return 0;
559 }
560
561 static void fsck_object_dir(const char *path)
562 {
563         struct progress *progress = NULL;
564
565         if (verbose)
566                 fprintf(stderr, "Checking object directory\n");
567
568         if (show_progress)
569                 progress = start_progress(_("Checking object directories"), 256);
570
571         for_each_loose_file_in_objdir(path, fsck_loose, fsck_cruft, fsck_subdir,
572                                       progress);
573         display_progress(progress, 256);
574         stop_progress(&progress);
575 }
576
577 static int fsck_head_link(void)
578 {
579         int null_is_error = 0;
580
581         if (verbose)
582                 fprintf(stderr, "Checking HEAD link\n");
583
584         head_points_at = resolve_ref_unsafe("HEAD", 0, &head_oid, NULL);
585         if (!head_points_at) {
586                 errors_found |= ERROR_REFS;
587                 return error("Invalid HEAD");
588         }
589         if (!strcmp(head_points_at, "HEAD"))
590                 /* detached HEAD */
591                 null_is_error = 1;
592         else if (!starts_with(head_points_at, "refs/heads/")) {
593                 errors_found |= ERROR_REFS;
594                 return error("HEAD points to something strange (%s)",
595                              head_points_at);
596         }
597         if (is_null_oid(&head_oid)) {
598                 if (null_is_error) {
599                         errors_found |= ERROR_REFS;
600                         return error("HEAD: detached HEAD points at nothing");
601                 }
602                 fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n",
603                         head_points_at + 11);
604         }
605         return 0;
606 }
607
608 static int fsck_cache_tree(struct cache_tree *it)
609 {
610         int i;
611         int err = 0;
612
613         if (verbose)
614                 fprintf(stderr, "Checking cache tree\n");
615
616         if (0 <= it->entry_count) {
617                 struct object *obj = parse_object(&it->oid);
618                 if (!obj) {
619                         error("%s: invalid sha1 pointer in cache-tree",
620                               oid_to_hex(&it->oid));
621                         errors_found |= ERROR_REFS;
622                         return 1;
623                 }
624                 obj->flags |= USED;
625                 if (name_objects)
626                         add_decoration(fsck_walk_options.object_names,
627                                 obj, xstrdup(":"));
628                 mark_object_reachable(obj);
629                 if (obj->type != OBJ_TREE)
630                         err |= objerror(obj, "non-tree in cache-tree");
631         }
632         for (i = 0; i < it->subtree_nr; i++)
633                 err |= fsck_cache_tree(it->down[i]->cache_tree);
634         return err;
635 }
636
637 static void mark_object_for_connectivity(const struct object_id *oid)
638 {
639         struct object *obj = lookup_unknown_object(oid->hash);
640         obj->flags |= HAS_OBJ;
641 }
642
643 static int mark_loose_for_connectivity(const struct object_id *oid,
644                                        const char *path,
645                                        void *data)
646 {
647         mark_object_for_connectivity(oid);
648         return 0;
649 }
650
651 static int mark_packed_for_connectivity(const struct object_id *oid,
652                                         struct packed_git *pack,
653                                         uint32_t pos,
654                                         void *data)
655 {
656         mark_object_for_connectivity(oid);
657         return 0;
658 }
659
660 static char const * const fsck_usage[] = {
661         N_("git fsck [<options>] [<object>...]"),
662         NULL
663 };
664
665 static struct option fsck_opts[] = {
666         OPT__VERBOSE(&verbose, N_("be verbose")),
667         OPT_BOOL(0, "unreachable", &show_unreachable, N_("show unreachable objects")),
668         OPT_BOOL(0, "dangling", &show_dangling, N_("show dangling objects")),
669         OPT_BOOL(0, "tags", &show_tags, N_("report tags")),
670         OPT_BOOL(0, "root", &show_root, N_("report root nodes")),
671         OPT_BOOL(0, "cache", &keep_cache_objects, N_("make index objects head nodes")),
672         OPT_BOOL(0, "reflogs", &include_reflogs, N_("make reflogs head nodes (default)")),
673         OPT_BOOL(0, "full", &check_full, N_("also consider packs and alternate objects")),
674         OPT_BOOL(0, "connectivity-only", &connectivity_only, N_("check only connectivity")),
675         OPT_BOOL(0, "strict", &check_strict, N_("enable more strict checking")),
676         OPT_BOOL(0, "lost-found", &write_lost_and_found,
677                                 N_("write dangling objects in .git/lost-found")),
678         OPT_BOOL(0, "progress", &show_progress, N_("show progress")),
679         OPT_BOOL(0, "name-objects", &name_objects, N_("show verbose names for reachable objects")),
680         OPT_END(),
681 };
682
683 int cmd_fsck(int argc, const char **argv, const char *prefix)
684 {
685         int i;
686         struct alternate_object_database *alt;
687
688         /* fsck knows how to handle missing promisor objects */
689         fetch_if_missing = 0;
690
691         errors_found = 0;
692         check_replace_refs = 0;
693
694         argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0);
695
696         fsck_walk_options.walk = mark_object;
697         fsck_obj_options.walk = mark_used;
698         fsck_obj_options.error_func = fsck_error_func;
699         if (check_strict)
700                 fsck_obj_options.strict = 1;
701
702         if (show_progress == -1)
703                 show_progress = isatty(2);
704         if (verbose)
705                 show_progress = 0;
706
707         if (write_lost_and_found) {
708                 check_full = 1;
709                 include_reflogs = 0;
710         }
711
712         if (name_objects)
713                 fsck_walk_options.object_names =
714                         xcalloc(1, sizeof(struct decoration));
715
716         git_config(fsck_config, NULL);
717
718         fsck_head_link();
719         if (connectivity_only) {
720                 for_each_loose_object(mark_loose_for_connectivity, NULL, 0);
721                 for_each_packed_object(mark_packed_for_connectivity, NULL, 0);
722         } else {
723                 struct alternate_object_database *alt_odb_list;
724
725                 fsck_object_dir(get_object_directory());
726
727                 prepare_alt_odb(the_repository);
728                 alt_odb_list = the_repository->objects->alt_odb_list;
729                 for (alt = alt_odb_list; alt; alt = alt->next)
730                         fsck_object_dir(alt->path);
731
732                 if (check_full) {
733                         struct packed_git *p;
734                         uint32_t total = 0, count = 0;
735                         struct progress *progress = NULL;
736
737                         if (show_progress) {
738                                 for (p = get_packed_git(the_repository); p;
739                                      p = p->next) {
740                                         if (open_pack_index(p))
741                                                 continue;
742                                         total += p->num_objects;
743                                 }
744
745                                 progress = start_progress(_("Checking objects"), total);
746                         }
747                         for (p = get_packed_git(the_repository); p;
748                              p = p->next) {
749                                 /* verify gives error messages itself */
750                                 if (verify_pack(p, fsck_obj_buffer,
751                                                 progress, count))
752                                         errors_found |= ERROR_PACK;
753                                 count += p->num_objects;
754                         }
755                         stop_progress(&progress);
756                 }
757
758                 if (fsck_finish(&fsck_obj_options))
759                         errors_found |= ERROR_OBJECT;
760         }
761
762         for (i = 0; i < argc; i++) {
763                 const char *arg = argv[i];
764                 struct object_id oid;
765                 if (!get_oid(arg, &oid)) {
766                         struct object *obj = lookup_object(oid.hash);
767
768                         if (!obj || !(obj->flags & HAS_OBJ)) {
769                                 if (is_promisor_object(&oid))
770                                         continue;
771                                 error("%s: object missing", oid_to_hex(&oid));
772                                 errors_found |= ERROR_OBJECT;
773                                 continue;
774                         }
775
776                         obj->flags |= USED;
777                         if (name_objects)
778                                 add_decoration(fsck_walk_options.object_names,
779                                         obj, xstrdup(arg));
780                         mark_object_reachable(obj);
781                         continue;
782                 }
783                 error("invalid parameter: expected sha1, got '%s'", arg);
784                 errors_found |= ERROR_OBJECT;
785         }
786
787         /*
788          * If we've not been given any explicit head information, do the
789          * default ones from .git/refs. We also consider the index file
790          * in this case (ie this implies --cache).
791          */
792         if (!argc) {
793                 get_default_heads();
794                 keep_cache_objects = 1;
795         }
796
797         if (keep_cache_objects) {
798                 verify_index_checksum = 1;
799                 verify_ce_order = 1;
800                 read_cache();
801                 for (i = 0; i < active_nr; i++) {
802                         unsigned int mode;
803                         struct blob *blob;
804                         struct object *obj;
805
806                         mode = active_cache[i]->ce_mode;
807                         if (S_ISGITLINK(mode))
808                                 continue;
809                         blob = lookup_blob(&active_cache[i]->oid);
810                         if (!blob)
811                                 continue;
812                         obj = &blob->object;
813                         obj->flags |= USED;
814                         if (name_objects)
815                                 add_decoration(fsck_walk_options.object_names,
816                                         obj,
817                                         xstrfmt(":%s", active_cache[i]->name));
818                         mark_object_reachable(obj);
819                 }
820                 if (active_cache_tree)
821                         fsck_cache_tree(active_cache_tree);
822         }
823
824         check_connectivity();
825         return errors_found;
826 }