diff options
Diffstat (limited to 'builtin/fsck.c')
| -rw-r--r-- | builtin/fsck.c | 684 |
1 files changed, 684 insertions, 0 deletions
diff --git a/builtin/fsck.c b/builtin/fsck.c new file mode 100644 index 0000000..0929c7f --- /dev/null +++ b/builtin/fsck.c @@ -0,0 +1,684 @@ +#include "builtin.h" +#include "cache.h" +#include "commit.h" +#include "tree.h" +#include "blob.h" +#include "tag.h" +#include "refs.h" +#include "pack.h" +#include "cache-tree.h" +#include "tree-walk.h" +#include "fsck.h" +#include "parse-options.h" +#include "dir.h" + +#define REACHABLE 0x0001 +#define SEEN 0x0002 + +static int show_root; +static int show_tags; +static int show_unreachable; +static int include_reflogs = 1; +static int check_full = 1; +static int check_strict; +static int keep_cache_objects; +static unsigned char head_sha1[20]; +static const char *head_points_at; +static int errors_found; +static int write_lost_and_found; +static int verbose; +#define ERROR_OBJECT 01 +#define ERROR_REACHABLE 02 + +#ifdef NO_D_INO_IN_DIRENT +#define SORT_DIRENT 0 +#define DIRENT_SORT_HINT(de) 0 +#else +#define SORT_DIRENT 1 +#define DIRENT_SORT_HINT(de) ((de)->d_ino) +#endif + +static void objreport(struct object *obj, const char *severity, + const char *err, va_list params) +{ + fprintf(stderr, "%s in %s %s: ", + severity, typename(obj->type), sha1_to_hex(obj->sha1)); + vfprintf(stderr, err, params); + fputs("\n", stderr); +} + +__attribute__((format (printf, 2, 3))) +static int objerror(struct object *obj, const char *err, ...) +{ + va_list params; + va_start(params, err); + errors_found |= ERROR_OBJECT; + objreport(obj, "error", err, params); + va_end(params); + return -1; +} + +__attribute__((format (printf, 3, 4))) +static int fsck_error_func(struct object *obj, int type, const char *err, ...) +{ + va_list params; + va_start(params, err); + objreport(obj, (type == FSCK_WARN) ? "warning" : "error", err, params); + va_end(params); + return (type == FSCK_WARN) ? 0 : 1; +} + +static struct object_array pending; + +static int mark_object(struct object *obj, int type, void *data) +{ + struct object *parent = data; + + if (!obj) { + printf("broken link from %7s %s\n", + typename(parent->type), sha1_to_hex(parent->sha1)); + printf("broken link from %7s %s\n", + (type == OBJ_ANY ? "unknown" : typename(type)), "unknown"); + errors_found |= ERROR_REACHABLE; + return 1; + } + + if (type != OBJ_ANY && obj->type != type) + objerror(parent, "wrong object type in link"); + + if (obj->flags & REACHABLE) + return 0; + obj->flags |= REACHABLE; + if (!obj->parsed) { + if (parent && !has_sha1_file(obj->sha1)) { + printf("broken link from %7s %s\n", + typename(parent->type), sha1_to_hex(parent->sha1)); + printf(" to %7s %s\n", + typename(obj->type), sha1_to_hex(obj->sha1)); + errors_found |= ERROR_REACHABLE; + } + return 1; + } + + add_object_array(obj, (void *) parent, &pending); + return 0; +} + +static void mark_object_reachable(struct object *obj) +{ + mark_object(obj, OBJ_ANY, NULL); +} + +static int traverse_one_object(struct object *obj, struct object *parent) +{ + int result; + struct tree *tree = NULL; + + if (obj->type == OBJ_TREE) { + obj->parsed = 0; + tree = (struct tree *)obj; + if (parse_tree(tree) < 0) + return 1; /* error already displayed */ + } + result = fsck_walk(obj, mark_object, obj); + if (tree) { + free(tree->buffer); + tree->buffer = NULL; + } + return result; +} + +static int traverse_reachable(void) +{ + int result = 0; + while (pending.nr) { + struct object_array_entry *entry; + struct object *obj, *parent; + + entry = pending.objects + --pending.nr; + obj = entry->item; + parent = (struct object *) entry->name; + result |= traverse_one_object(obj, parent); + } + return !!result; +} + +static int mark_used(struct object *obj, int type, void *data) +{ + if (!obj) + return 1; + obj->used = 1; + return 0; +} + +/* + * Check a single reachable object + */ +static void check_reachable_object(struct object *obj) +{ + /* + * We obviously want the object to be parsed, + * except if it was in a pack-file and we didn't + * do a full fsck + */ + if (!obj->parsed) { + if (has_sha1_pack(obj->sha1)) + return; /* it is in pack - forget about it */ + printf("missing %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1)); + errors_found |= ERROR_REACHABLE; + return; + } +} + +/* + * Check a single unreachable object + */ +static void check_unreachable_object(struct object *obj) +{ + /* + * Missing unreachable object? Ignore it. It's not like + * we miss it (since it can't be reached), nor do we want + * to complain about it being unreachable (since it does + * not exist). + */ + if (!obj->parsed) + return; + + /* + * Unreachable object that exists? Show it if asked to, + * since this is something that is prunable. + */ + if (show_unreachable) { + printf("unreachable %s %s\n", typename(obj->type), sha1_to_hex(obj->sha1)); + return; + } + + /* + * "!used" means that nothing at all points to it, including + * other unreachable objects. In other words, it's the "tip" + * of some set of unreachable objects, usually a commit that + * got dropped. + * + * Such starting points are more interesting than some random + * set of unreachable objects, so we show them even if the user + * hasn't asked for _all_ unreachable objects. If you have + * deleted a branch by mistake, this is a prime candidate to + * start looking at, for example. + */ + if (!obj->used) { + printf("dangling %s %s\n", typename(obj->type), + sha1_to_hex(obj->sha1)); + if (write_lost_and_found) { + char *filename = git_path("lost-found/%s/%s", + obj->type == OBJ_COMMIT ? "commit" : "other", + sha1_to_hex(obj->sha1)); + FILE *f; + + if (safe_create_leading_directories(filename)) { + error("Could not create lost-found"); + return; + } + if (!(f = fopen(filename, "w"))) + die_errno("Could not open '%s'", filename); + if (obj->type == OBJ_BLOB) { + enum object_type type; + unsigned long size; + char *buf = read_sha1_file(obj->sha1, + &type, &size); + if (buf) { + if (fwrite(buf, size, 1, f) != 1) + die_errno("Could not write '%s'", + filename); + free(buf); + } + } else + fprintf(f, "%s\n", sha1_to_hex(obj->sha1)); + if (fclose(f)) + die_errno("Could not finish '%s'", + filename); + } + return; + } + + /* + * Otherwise? It's there, it's unreachable, and some other unreachable + * object points to it. Ignore it - it's not interesting, and we showed + * all the interesting cases above. + */ +} + +static void check_object(struct object *obj) +{ + if (verbose) + fprintf(stderr, "Checking %s\n", sha1_to_hex(obj->sha1)); + + if (obj->flags & REACHABLE) + check_reachable_object(obj); + else + check_unreachable_object(obj); +} + +static void check_connectivity(void) +{ + int i, max; + + /* Traverse the pending reachable objects */ + traverse_reachable(); + + /* Look up all the requirements, warn about missing objects.. */ + max = get_max_object_index(); + if (verbose) + fprintf(stderr, "Checking connectivity (%d objects)\n", max); + + for (i = 0; i < max; i++) { + struct object *obj = get_indexed_object(i); + + if (obj) + check_object(obj); + } +} + +static int fsck_sha1(const unsigned char *sha1) +{ + struct object *obj = parse_object(sha1); + if (!obj) { + errors_found |= ERROR_OBJECT; + return error("%s: object corrupt or missing", + sha1_to_hex(sha1)); + } + if (obj->flags & SEEN) + return 0; + obj->flags |= SEEN; + + if (verbose) + fprintf(stderr, "Checking %s %s\n", + typename(obj->type), sha1_to_hex(obj->sha1)); + + if (fsck_walk(obj, mark_used, NULL)) + objerror(obj, "broken links"); + if (fsck_object(obj, check_strict, fsck_error_func)) + return -1; + + if (obj->type == OBJ_TREE) { + struct tree *item = (struct tree *) obj; + + free(item->buffer); + item->buffer = NULL; + } + + if (obj->type == OBJ_COMMIT) { + struct commit *commit = (struct commit *) obj; + + free(commit->buffer); + commit->buffer = NULL; + + if (!commit->parents && show_root) + printf("root %s\n", sha1_to_hex(commit->object.sha1)); + } + + if (obj->type == OBJ_TAG) { + struct tag *tag = (struct tag *) obj; + + if (show_tags && tag->tagged) { + printf("tagged %s %s", typename(tag->tagged->type), sha1_to_hex(tag->tagged->sha1)); + printf(" (%s) in %s\n", tag->tag, sha1_to_hex(tag->object.sha1)); + } + } + + return 0; +} + +/* + * This is the sorting chunk size: make it reasonably + * big so that we can sort well.. + */ +#define MAX_SHA1_ENTRIES (1024) + +struct sha1_entry { + unsigned long ino; + unsigned char sha1[20]; +}; + +static struct { + unsigned long nr; + struct sha1_entry *entry[MAX_SHA1_ENTRIES]; +} sha1_list; + +static int ino_compare(const void *_a, const void *_b) +{ + const struct sha1_entry *a = _a, *b = _b; + unsigned long ino1 = a->ino, ino2 = b->ino; + return ino1 < ino2 ? -1 : ino1 > ino2 ? 1 : 0; +} + +static void fsck_sha1_list(void) +{ + int i, nr = sha1_list.nr; + + if (SORT_DIRENT) + qsort(sha1_list.entry, nr, + sizeof(struct sha1_entry *), ino_compare); + for (i = 0; i < nr; i++) { + struct sha1_entry *entry = sha1_list.entry[i]; + unsigned char *sha1 = entry->sha1; + + sha1_list.entry[i] = NULL; + fsck_sha1(sha1); + free(entry); + } + sha1_list.nr = 0; +} + +static void add_sha1_list(unsigned char *sha1, unsigned long ino) +{ + struct sha1_entry *entry = xmalloc(sizeof(*entry)); + int nr; + + entry->ino = ino; + hashcpy(entry->sha1, sha1); + nr = sha1_list.nr; + if (nr == MAX_SHA1_ENTRIES) { + fsck_sha1_list(); + nr = 0; + } + sha1_list.entry[nr] = entry; + sha1_list.nr = ++nr; +} + +static void fsck_dir(int i, char *path) +{ + DIR *dir = opendir(path); + struct dirent *de; + + if (!dir) + return; + + if (verbose) + fprintf(stderr, "Checking directory %s\n", path); + + while ((de = readdir(dir)) != NULL) { + char name[100]; + unsigned char sha1[20]; + + if (is_dot_or_dotdot(de->d_name)) + continue; + if (strlen(de->d_name) == 38) { + sprintf(name, "%02x", i); + memcpy(name+2, de->d_name, 39); + if (get_sha1_hex(name, sha1) < 0) + break; + add_sha1_list(sha1, DIRENT_SORT_HINT(de)); + continue; + } + if (!prefixcmp(de->d_name, "tmp_obj_")) + continue; + fprintf(stderr, "bad sha1 file: %s/%s\n", path, de->d_name); + } + closedir(dir); +} + +static int default_refs; + +static int fsck_handle_reflog_ent(unsigned char *osha1, unsigned char *nsha1, + const char *email, unsigned long timestamp, int tz, + const char *message, void *cb_data) +{ + struct object *obj; + + if (verbose) + fprintf(stderr, "Checking reflog %s->%s\n", + sha1_to_hex(osha1), sha1_to_hex(nsha1)); + + if (!is_null_sha1(osha1)) { + obj = lookup_object(osha1); + if (obj) { + obj->used = 1; + mark_object_reachable(obj); + } + } + obj = lookup_object(nsha1); + if (obj) { + obj->used = 1; + mark_object_reachable(obj); + } + return 0; +} + +static int fsck_handle_reflog(const char *logname, const unsigned char *sha1, int flag, void *cb_data) +{ + for_each_reflog_ent(logname, fsck_handle_reflog_ent, NULL); + return 0; +} + +static int is_branch(const char *refname) +{ + return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/"); +} + +static int fsck_handle_ref(const char *refname, const unsigned char *sha1, int flag, void *cb_data) +{ + struct object *obj; + + obj = parse_object(sha1); + if (!obj) { + error("%s: invalid sha1 pointer %s", refname, sha1_to_hex(sha1)); + /* We'll continue with the rest despite the error.. */ + return 0; + } + if (obj->type != OBJ_COMMIT && is_branch(refname)) + error("%s: not a commit", refname); + default_refs++; + obj->used = 1; + mark_object_reachable(obj); + + return 0; +} + +static void get_default_heads(void) +{ + if (head_points_at && !is_null_sha1(head_sha1)) + fsck_handle_ref("HEAD", head_sha1, 0, NULL); + for_each_ref(fsck_handle_ref, NULL); + if (include_reflogs) + for_each_reflog(fsck_handle_reflog, NULL); + + /* + * Not having any default heads isn't really fatal, but + * it does mean that "--unreachable" no longer makes any + * sense (since in this case everything will obviously + * be unreachable by definition. + * + * Showing dangling objects is valid, though (as those + * dangling objects are likely lost heads). + * + * So we just print a warning about it, and clear the + * "show_unreachable" flag. + */ + if (!default_refs) { + fprintf(stderr, "notice: No default references\n"); + show_unreachable = 0; + } +} + +static void fsck_object_dir(const char *path) +{ + int i; + + if (verbose) + fprintf(stderr, "Checking object directory\n"); + + for (i = 0; i < 256; i++) { + static char dir[4096]; + sprintf(dir, "%s/%02x", path, i); + fsck_dir(i, dir); + } + fsck_sha1_list(); +} + +static int fsck_head_link(void) +{ + int flag; + int null_is_error = 0; + + if (verbose) + fprintf(stderr, "Checking HEAD link\n"); + + head_points_at = resolve_ref("HEAD", head_sha1, 0, &flag); + if (!head_points_at) + return error("Invalid HEAD"); + if (!strcmp(head_points_at, "HEAD")) + /* detached HEAD */ + null_is_error = 1; + else if (prefixcmp(head_points_at, "refs/heads/")) + return error("HEAD points to something strange (%s)", + head_points_at); + if (is_null_sha1(head_sha1)) { + if (null_is_error) + return error("HEAD: detached HEAD points at nothing"); + fprintf(stderr, "notice: HEAD points to an unborn branch (%s)\n", + head_points_at + 11); + } + return 0; +} + +static int fsck_cache_tree(struct cache_tree *it) +{ + int i; + int err = 0; + + if (verbose) + fprintf(stderr, "Checking cache tree\n"); + + if (0 <= it->entry_count) { + struct object *obj = parse_object(it->sha1); + if (!obj) { + error("%s: invalid sha1 pointer in cache-tree", + sha1_to_hex(it->sha1)); + return 1; + } + mark_object_reachable(obj); + obj->used = 1; + if (obj->type != OBJ_TREE) + err |= objerror(obj, "non-tree in cache-tree"); + } + for (i = 0; i < it->subtree_nr; i++) + err |= fsck_cache_tree(it->down[i]->cache_tree); + return err; +} + +static char const * const fsck_usage[] = { + "git fsck [options] [<object>...]", + NULL +}; + +static struct option fsck_opts[] = { + OPT__VERBOSE(&verbose), + OPT_BOOLEAN(0, "unreachable", &show_unreachable, "show unreachable objects"), + OPT_BOOLEAN(0, "tags", &show_tags, "report tags"), + OPT_BOOLEAN(0, "root", &show_root, "report root nodes"), + OPT_BOOLEAN(0, "cache", &keep_cache_objects, "make index objects head nodes"), + OPT_BOOLEAN(0, "reflogs", &include_reflogs, "make reflogs head nodes (default)"), + OPT_BOOLEAN(0, "full", &check_full, "also consider packs and alternate objects"), + OPT_BOOLEAN(0, "strict", &check_strict, "enable more strict checking"), + OPT_BOOLEAN(0, "lost-found", &write_lost_and_found, + "write dangling objects in .git/lost-found"), + OPT_END(), +}; + +int cmd_fsck(int argc, const char **argv, const char *prefix) +{ + int i, heads; + struct alternate_object_database *alt; + + errors_found = 0; + read_replace_refs = 0; + + argc = parse_options(argc, argv, prefix, fsck_opts, fsck_usage, 0); + if (write_lost_and_found) { + check_full = 1; + include_reflogs = 0; + } + + fsck_head_link(); + fsck_object_dir(get_object_directory()); + + prepare_alt_odb(); + for (alt = alt_odb_list; alt; alt = alt->next) { + char namebuf[PATH_MAX]; + int namelen = alt->name - alt->base; + memcpy(namebuf, alt->base, namelen); + namebuf[namelen - 1] = 0; + fsck_object_dir(namebuf); + } + + if (check_full) { + struct packed_git *p; + + prepare_packed_git(); + for (p = packed_git; p; p = p->next) + /* verify gives error messages itself */ + verify_pack(p); + + for (p = packed_git; p; p = p->next) { + uint32_t j, num; + if (open_pack_index(p)) + continue; + num = p->num_objects; + for (j = 0; j < num; j++) + fsck_sha1(nth_packed_object_sha1(p, j)); + } + } + + heads = 0; + for (i = 0; i < argc; i++) { + const char *arg = argv[i]; + unsigned char sha1[20]; + if (!get_sha1(arg, sha1)) { + struct object *obj = lookup_object(sha1); + + /* Error is printed by lookup_object(). */ + if (!obj) + continue; + + obj->used = 1; + mark_object_reachable(obj); + heads++; + continue; + } + error("invalid parameter: expected sha1, got '%s'", arg); + } + + /* + * If we've not been given any explicit head information, do the + * default ones from .git/refs. We also consider the index file + * in this case (ie this implies --cache). + */ + if (!heads) { + get_default_heads(); + keep_cache_objects = 1; + } + + if (keep_cache_objects) { + read_cache(); + for (i = 0; i < active_nr; i++) { + unsigned int mode; + struct blob *blob; + struct object *obj; + + mode = active_cache[i]->ce_mode; + if (S_ISGITLINK(mode)) + continue; + blob = lookup_blob(active_cache[i]->sha1); + if (!blob) + continue; + obj = &blob->object; + obj->used = 1; + mark_object_reachable(obj); + } + if (active_cache_tree) + fsck_cache_tree(active_cache_tree); + } + + check_connectivity(); + return errors_found; +} |