]> git.ipfire.org Git - thirdparty/git.git/blobdiff - fsck.c
Merge branch 'ab/pager-exit-log'
[thirdparty/git.git] / fsck.c
diff --git a/fsck.c b/fsck.c
index a8870a54b6ad75f0d55f0fa16d69aa6ff3350866..71134fdefaa561ced0cfa3659eaa34155e9be5ce 100644 (file)
--- a/fsck.c
+++ b/fsck.c
@@ -45,21 +45,17 @@ static struct oidset gitmodules_done = OIDSET_INIT;
        FUNC(MISSING_AUTHOR, ERROR) \
        FUNC(MISSING_COMMITTER, ERROR) \
        FUNC(MISSING_EMAIL, ERROR) \
-       FUNC(MISSING_GRAFT, ERROR) \
        FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
        FUNC(MISSING_OBJECT, ERROR) \
-       FUNC(MISSING_PARENT, ERROR) \
        FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
        FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
        FUNC(MISSING_TAG, ERROR) \
        FUNC(MISSING_TAG_ENTRY, ERROR) \
-       FUNC(MISSING_TAG_OBJECT, ERROR) \
        FUNC(MISSING_TREE, ERROR) \
        FUNC(MISSING_TREE_OBJECT, ERROR) \
        FUNC(MISSING_TYPE, ERROR) \
        FUNC(MISSING_TYPE_ENTRY, ERROR) \
        FUNC(MULTIPLE_AUTHORS, ERROR) \
-       FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
        FUNC(TREE_NOT_SORTED, ERROR) \
        FUNC(UNKNOWN_TYPE, ERROR) \
        FUNC(ZERO_PADDED_DATE, ERROR) \
@@ -84,7 +80,9 @@ static struct oidset gitmodules_done = OIDSET_INIT;
        /* infos (reported as warnings, but ignored by default) */ \
        FUNC(GITMODULES_PARSE, INFO) \
        FUNC(BAD_TAG_NAME, INFO) \
-       FUNC(MISSING_TAGGER_ENTRY, INFO)
+       FUNC(MISSING_TAGGER_ENTRY, INFO) \
+       /* ignored (elevated when requested) */ \
+       FUNC(EXTRA_HEADER_ENTRY, IGNORE)
 
 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
 enum fsck_msg_id {
@@ -184,41 +182,6 @@ static int fsck_msg_type(enum fsck_msg_id msg_id,
        return msg_type;
 }
 
-static void init_skiplist(struct fsck_options *options, const char *path)
-{
-       FILE *fp;
-       struct strbuf sb = STRBUF_INIT;
-       struct object_id oid;
-
-       fp = fopen(path, "r");
-       if (!fp)
-               die("Could not open skip list: %s", path);
-       while (!strbuf_getline(&sb, fp)) {
-               const char *p;
-               const char *hash;
-
-               /*
-                * Allow trailing comments, leading whitespace
-                * (including before commits), and empty or whitespace
-                * only lines.
-                */
-               hash = strchr(sb.buf, '#');
-               if (hash)
-                       strbuf_setlen(&sb, hash - sb.buf);
-               strbuf_trim(&sb);
-               if (!sb.len)
-                       continue;
-
-               if (parse_oid_hex(sb.buf, &oid, &p) || *p != '\0')
-                       die("Invalid SHA-1: %s", sb.buf);
-               oidset_insert(&options->skiplist, &oid);
-       }
-       if (ferror(fp))
-               die_errno("Could not read '%s'", path);
-       fclose(fp);
-       strbuf_release(&sb);
-}
-
 static int parse_msg_type(const char *str)
 {
        if (!strcmp(str, "error"))
@@ -287,7 +250,7 @@ void fsck_set_msg_types(struct fsck_options *options, const char *values)
                if (!strcmp(buf, "skiplist")) {
                        if (equal == len)
                                die("skiplist requires a path");
-                       init_skiplist(options, buf + equal + 1);
+                       oidset_parse_file(&options->skiplist, buf + equal + 1);
                        buf += len + 1;
                        continue;
                }
@@ -319,14 +282,16 @@ static void append_msg_id(struct strbuf *sb, const char *msg_id)
        strbuf_addstr(sb, ": ");
 }
 
-static int object_on_skiplist(struct fsck_options *opts, struct object *obj)
+static int object_on_skiplist(struct fsck_options *opts,
+                             const struct object_id *oid)
 {
-       return opts && obj && oidset_contains(&opts->skiplist, &obj->oid);
+       return opts && oid && oidset_contains(&opts->skiplist, oid);
 }
 
-__attribute__((format (printf, 4, 5)))
-static int report(struct fsck_options *options, struct object *object,
-       enum fsck_msg_id id, const char *fmt, ...)
+__attribute__((format (printf, 5, 6)))
+static int report(struct fsck_options *options,
+                 const struct object_id *oid, enum object_type object_type,
+                 enum fsck_msg_id id, const char *fmt, ...)
 {
        va_list ap;
        struct strbuf sb = STRBUF_INIT;
@@ -335,7 +300,7 @@ static int report(struct fsck_options *options, struct object *object,
        if (msg_type == FSCK_IGNORE)
                return 0;
 
-       if (object_on_skiplist(options, object))
+       if (object_on_skiplist(options, oid))
                return 0;
 
        if (msg_type == FSCK_FATAL)
@@ -347,49 +312,71 @@ static int report(struct fsck_options *options, struct object *object,
 
        va_start(ap, fmt);
        strbuf_vaddf(&sb, fmt, ap);
-       result = options->error_func(options, object, msg_type, sb.buf);
+       result = options->error_func(options, oid, object_type,
+                                    msg_type, sb.buf);
        strbuf_release(&sb);
        va_end(ap);
 
        return result;
 }
 
-static char *get_object_name(struct fsck_options *options, struct object *obj)
+void fsck_enable_object_names(struct fsck_options *options)
 {
        if (!options->object_names)
+               options->object_names = kh_init_oid_map();
+}
+
+const char *fsck_get_object_name(struct fsck_options *options,
+                                const struct object_id *oid)
+{
+       khiter_t pos;
+       if (!options->object_names)
+               return NULL;
+       pos = kh_get_oid_map(options->object_names, *oid);
+       if (pos >= kh_end(options->object_names))
                return NULL;
-       return lookup_decoration(options->object_names, obj);
+       return kh_value(options->object_names, pos);
 }
 
-static void put_object_name(struct fsck_options *options, struct object *obj,
-       const char *fmt, ...)
+void fsck_put_object_name(struct fsck_options *options,
+                         const struct object_id *oid,
+                         const char *fmt, ...)
 {
        va_list ap;
        struct strbuf buf = STRBUF_INIT;
-       char *existing;
+       khiter_t pos;
+       int hashret;
 
        if (!options->object_names)
                return;
-       existing = lookup_decoration(options->object_names, obj);
-       if (existing)
+
+       pos = kh_put_oid_map(options->object_names, *oid, &hashret);
+       if (!hashret)
                return;
        va_start(ap, fmt);
        strbuf_vaddf(&buf, fmt, ap);
-       add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
+       kh_value(options->object_names, pos) = strbuf_detach(&buf, NULL);
        va_end(ap);
 }
 
-static const char *describe_object(struct fsck_options *o, struct object *obj)
+const char *fsck_describe_object(struct fsck_options *options,
+                                const struct object_id *oid)
 {
-       static struct strbuf buf = STRBUF_INIT;
-       char *name;
-
-       strbuf_reset(&buf);
-       strbuf_addstr(&buf, oid_to_hex(&obj->oid));
-       if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
-               strbuf_addf(&buf, " (%s)", name);
+       static struct strbuf bufs[] = {
+               STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
+       };
+       static int b = 0;
+       struct strbuf *buf;
+       const char *name = fsck_get_object_name(options, oid);
+
+       buf = bufs + b;
+       b = (b + 1) % ARRAY_SIZE(bufs);
+       strbuf_reset(buf);
+       strbuf_addstr(buf, oid_to_hex(oid));
+       if (name)
+               strbuf_addf(buf, " (%s)", name);
 
-       return buf.buf;
+       return buf->buf;
 }
 
 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
@@ -402,7 +389,7 @@ static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *op
        if (parse_tree(tree))
                return -1;
 
-       name = get_object_name(options, &tree->object);
+       name = fsck_get_object_name(options, &tree->object.oid);
        if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
                return -1;
        while (tree_entry_gently(&desc, &entry)) {
@@ -413,22 +400,23 @@ static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *op
                        continue;
 
                if (S_ISDIR(entry.mode)) {
-                       obj = (struct object *)lookup_tree(the_repository, entry.oid);
+                       obj = (struct object *)lookup_tree(the_repository, &entry.oid);
                        if (name && obj)
-                               put_object_name(options, obj, "%s%s/", name,
-                                       entry.path);
+                               fsck_put_object_name(options, &entry.oid, "%s%s/",
+                                                    name, entry.path);
                        result = options->walk(obj, OBJ_TREE, data, options);
                }
                else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
-                       obj = (struct object *)lookup_blob(the_repository, entry.oid);
+                       obj = (struct object *)lookup_blob(the_repository, &entry.oid);
                        if (name && obj)
-                               put_object_name(options, obj, "%s%s", name,
-                                       entry.path);
+                               fsck_put_object_name(options, &entry.oid, "%s%s",
+                                                    name, entry.path);
                        result = options->walk(obj, OBJ_BLOB, data, options);
                }
                else {
                        result = error("in tree %s: entry %s has bad mode %.6o",
-                                       describe_object(options, &tree->object), entry.path, entry.mode);
+                                      fsck_describe_object(options, &tree->object.oid),
+                                      entry.path, entry.mode);
                }
                if (result < 0)
                        return result;
@@ -449,10 +437,10 @@ static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_optio
        if (parse_commit(commit))
                return -1;
 
-       name = get_object_name(options, &commit->object);
+       name = fsck_get_object_name(options, &commit->object.oid);
        if (name)
-               put_object_name(options, &get_commit_tree(commit)->object,
-                               "%s:", name);
+               fsck_put_object_name(options, get_commit_tree_oid(commit),
+                                    "%s:", name);
 
        result = options->walk((struct object *)get_commit_tree(commit),
                               OBJ_TREE, data, options);
@@ -475,21 +463,27 @@ static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_optio
                                generation += power * (name[--len] - '0');
                        if (power > 1 && len && name[len - 1] == '~')
                                name_prefix_len = len - 1;
+                       else {
+                               /* Maybe a non-first parent, e.g. HEAD^2 */
+                               generation = 0;
+                               name_prefix_len = len;
+                       }
                }
        }
 
        while (parents) {
                if (name) {
-                       struct object *obj = &parents->item->object;
+                       struct object_id *oid = &parents->item->object.oid;
 
                        if (counter++)
-                               put_object_name(options, obj, "%s^%d",
-                                       name, counter);
+                               fsck_put_object_name(options, oid, "%s^%d",
+                                                    name, counter);
                        else if (generation > 0)
-                               put_object_name(options, obj, "%.*s~%d",
-                                       name_prefix_len, name, generation + 1);
+                               fsck_put_object_name(options, oid, "%.*s~%d",
+                                                    name_prefix_len, name,
+                                                    generation + 1);
                        else
-                               put_object_name(options, obj, "%s^", name);
+                               fsck_put_object_name(options, oid, "%s^", name);
                }
                result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
                if (result < 0)
@@ -503,12 +497,12 @@ static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_optio
 
 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 {
-       char *name = get_object_name(options, &tag->object);
+       const char *name = fsck_get_object_name(options, &tag->object.oid);
 
        if (parse_tag(tag))
                return -1;
        if (name)
-               put_object_name(options, tag->tagged, "%s", name);
+               fsck_put_object_name(options, &tag->tagged->oid, "%s", name);
        return options->walk(tag->tagged, OBJ_ANY, data, options);
 }
 
@@ -530,11 +524,34 @@ int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
        case OBJ_TAG:
                return fsck_walk_tag((struct tag *)obj, data, options);
        default:
-               error("Unknown object type for %s", describe_object(options, obj));
+               error("Unknown object type for %s",
+                     fsck_describe_object(options, &obj->oid));
                return -1;
        }
 }
 
+struct name_stack {
+       const char **names;
+       size_t nr, alloc;
+};
+
+static void name_stack_push(struct name_stack *stack, const char *name)
+{
+       ALLOC_GROW(stack->names, stack->nr + 1, stack->alloc);
+       stack->names[stack->nr++] = name;
+}
+
+static const char *name_stack_pop(struct name_stack *stack)
+{
+       return stack->nr ? stack->names[--stack->nr] : NULL;
+}
+
+static void name_stack_clear(struct name_stack *stack)
+{
+       FREE_AND_NULL(stack->names);
+       stack->nr = stack->alloc = 0;
+}
+
 /*
  * The entries in a tree are ordered in the _path_ order,
  * which means that a directory entry is ordered by adding
@@ -546,7 +563,14 @@ int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 #define TREE_UNORDERED (-1)
 #define TREE_HAS_DUPS  (-2)
 
-static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
+static int is_less_than_slash(unsigned char c)
+{
+       return '\0' < c && c < '/';
+}
+
+static int verify_ordered(unsigned mode1, const char *name1,
+                         unsigned mode2, const char *name2,
+                         struct name_stack *candidates)
 {
        int len1 = strlen(name1);
        int len2 = strlen(name2);
@@ -578,10 +602,47 @@ static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, con
                c1 = '/';
        if (!c2 && S_ISDIR(mode2))
                c2 = '/';
+
+       /*
+        * There can be non-consecutive duplicates due to the implicitly
+        * added slash, e.g.:
+        *
+        *   foo
+        *   foo.bar
+        *   foo.bar.baz
+        *   foo.bar/
+        *   foo/
+        *
+        * Record non-directory candidates (like "foo" and "foo.bar" in
+        * the example) on a stack and check directory candidates (like
+        * foo/" and "foo.bar/") against that stack.
+        */
+       if (!c1 && is_less_than_slash(c2)) {
+               name_stack_push(candidates, name1);
+       } else if (c2 == '/' && is_less_than_slash(c1)) {
+               for (;;) {
+                       const char *p;
+                       const char *f_name = name_stack_pop(candidates);
+
+                       if (!f_name)
+                               break;
+                       if (!skip_prefix(name2, f_name, &p))
+                               continue;
+                       if (!*p)
+                               return TREE_HAS_DUPS;
+                       if (is_less_than_slash(*p)) {
+                               name_stack_push(candidates, f_name);
+                               break;
+                       }
+               }
+       }
+
        return c1 < c2 ? 0 : TREE_UNORDERED;
 }
 
-static int fsck_tree(struct tree *item, struct fsck_options *options)
+static int fsck_tree(const struct object_id *oid,
+                    const char *buffer, unsigned long size,
+                    struct fsck_options *options)
 {
        int retval = 0;
        int has_null_sha1 = 0;
@@ -597,9 +658,10 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
        struct tree_desc desc;
        unsigned o_mode;
        const char *o_name;
+       struct name_stack df_dup_candidates = { NULL };
 
-       if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
-               retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
+       if (init_tree_desc_gently(&desc, buffer, size)) {
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
                return retval;
        }
 
@@ -607,7 +669,7 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
        o_name = NULL;
 
        while (desc.size) {
-               unsigned mode;
+               unsigned short mode;
                const char *name, *backslash;
                const struct object_id *oid;
 
@@ -625,7 +687,8 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
                        if (!S_ISLNK(mode))
                                oidset_insert(&gitmodules_found, oid);
                        else
-                               retval += report(options, &item->object,
+                               retval += report(options,
+                                                oid, OBJ_TREE,
                                                 FSCK_MSG_GITMODULES_SYMLINK,
                                                 ".gitmodules is a symbolic link");
                }
@@ -638,7 +701,7 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
                                        if (!S_ISLNK(mode))
                                                oidset_insert(&gitmodules_found, oid);
                                        else
-                                               retval += report(options, &item->object,
+                                               retval += report(options, oid, OBJ_TREE,
                                                                 FSCK_MSG_GITMODULES_SYMLINK,
                                                                 ".gitmodules is a symbolic link");
                                }
@@ -647,7 +710,7 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
                }
 
                if (update_tree_entry_gently(&desc)) {
-                       retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
+                       retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
                        break;
                }
 
@@ -675,7 +738,8 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
                }
 
                if (o_name) {
-                       switch (verify_ordered(o_mode, o_name, mode, name)) {
+                       switch (verify_ordered(o_mode, o_name, mode, name,
+                                              &df_dup_candidates)) {
                        case TREE_UNORDERED:
                                not_properly_sorted = 1;
                                break;
@@ -691,31 +755,34 @@ static int fsck_tree(struct tree *item, struct fsck_options *options)
                o_name = name;
        }
 
+       name_stack_clear(&df_dup_candidates);
+
        if (has_null_sha1)
-               retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
        if (has_full_path)
-               retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
        if (has_empty_name)
-               retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
        if (has_dot)
-               retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOT, "contains '.'");
        if (has_dotdot)
-               retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOTDOT, "contains '..'");
        if (has_dotgit)
-               retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
        if (has_zero_pad)
-               retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
        if (has_bad_modes)
-               retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
        if (has_dup_entries)
-               retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
        if (not_properly_sorted)
-               retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
+               retval += report(options, oid, OBJ_TREE, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
        return retval;
 }
 
 static int verify_headers(const void *data, unsigned long size,
-                         struct object *obj, struct fsck_options *options)
+                         const struct object_id *oid, enum object_type type,
+                         struct fsck_options *options)
 {
        const char *buffer = (const char *)data;
        unsigned long i;
@@ -723,7 +790,7 @@ static int verify_headers(const void *data, unsigned long size,
        for (i = 0; i < size; i++) {
                switch (buffer[i]) {
                case '\0':
-                       return report(options, obj,
+                       return report(options, oid, type,
                                FSCK_MSG_NUL_IN_HEADER,
                                "unterminated header: NUL at offset %ld", i);
                case '\n':
@@ -741,11 +808,13 @@ static int verify_headers(const void *data, unsigned long size,
        if (size && buffer[size - 1] == '\n')
                return 0;
 
-       return report(options, obj,
+       return report(options, oid, type,
                FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 }
 
-static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
+static int fsck_ident(const char **ident,
+                     const struct object_id *oid, enum object_type type,
+                     struct fsck_options *options)
 {
        const char *p = *ident;
        char *end;
@@ -755,28 +824,28 @@ static int fsck_ident(const char **ident, struct object *obj, struct fsck_option
                (*ident)++;
 
        if (*p == '<')
-               return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
+               return report(options, oid, type, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
        p += strcspn(p, "<>\n");
        if (*p == '>')
-               return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
+               return report(options, oid, type, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
        if (*p != '<')
-               return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
+               return report(options, oid, type, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
        if (p[-1] != ' ')
-               return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
+               return report(options, oid, type, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
        p++;
        p += strcspn(p, "<>\n");
        if (*p != '>')
-               return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
+               return report(options, oid, type, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
        p++;
        if (*p != ' ')
-               return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
+               return report(options, oid, type, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
        p++;
        if (*p == '0' && p[1] != ' ')
-               return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
+               return report(options, oid, type, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
        if (date_overflows(parse_timestamp(p, &end, 10)))
-               return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
+               return report(options, oid, type, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
        if ((end == p || *end != ' '))
-               return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
+               return report(options, oid, type, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
        p = end + 1;
        if ((*p != '+' && *p != '-') ||
            !isdigit(p[1]) ||
@@ -784,83 +853,60 @@ static int fsck_ident(const char **ident, struct object *obj, struct fsck_option
            !isdigit(p[3]) ||
            !isdigit(p[4]) ||
            (p[5] != '\n'))
-               return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
+               return report(options, oid, type, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
        p += 6;
        return 0;
 }
 
-static int fsck_commit_buffer(struct commit *commit, const char *buffer,
-       unsigned long size, struct fsck_options *options)
+static int fsck_commit(const struct object_id *oid,
+                      const char *buffer, unsigned long size,
+                      struct fsck_options *options)
 {
-       struct object_id tree_oid, oid;
-       struct commit_graft *graft;
-       unsigned parent_count, parent_line_count = 0, author_count;
+       struct object_id tree_oid, parent_oid;
+       unsigned author_count;
        int err;
        const char *buffer_begin = buffer;
        const char *p;
 
-       if (verify_headers(buffer, size, &commit->object, options))
+       if (verify_headers(buffer, size, oid, OBJ_COMMIT, options))
                return -1;
 
        if (!skip_prefix(buffer, "tree ", &buffer))
-               return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
+               return report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
        if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
-               err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
+               err = report(options, oid, OBJ_COMMIT, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
                if (err)
                        return err;
        }
        buffer = p + 1;
        while (skip_prefix(buffer, "parent ", &buffer)) {
-               if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
-                       err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
+               if (parse_oid_hex(buffer, &parent_oid, &p) || *p != '\n') {
+                       err = report(options, oid, OBJ_COMMIT, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
                        if (err)
                                return err;
                }
                buffer = p + 1;
-               parent_line_count++;
-       }
-       graft = lookup_commit_graft(the_repository, &commit->object.oid);
-       parent_count = commit_list_count(commit->parents);
-       if (graft) {
-               if (graft->nr_parent == -1 && !parent_count)
-                       ; /* shallow commit */
-               else if (graft->nr_parent != parent_count) {
-                       err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
-                       if (err)
-                               return err;
-               }
-       } else {
-               if (parent_count != parent_line_count) {
-                       err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
-                       if (err)
-                               return err;
-               }
        }
        author_count = 0;
        while (skip_prefix(buffer, "author ", &buffer)) {
                author_count++;
-               err = fsck_ident(&buffer, &commit->object, options);
+               err = fsck_ident(&buffer, oid, OBJ_COMMIT, options);
                if (err)
                        return err;
        }
        if (author_count < 1)
-               err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
+               err = report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
        else if (author_count > 1)
-               err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
+               err = report(options, oid, OBJ_COMMIT, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
        if (err)
                return err;
        if (!skip_prefix(buffer, "committer ", &buffer))
-               return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
-       err = fsck_ident(&buffer, &commit->object, options);
+               return report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
+       err = fsck_ident(&buffer, oid, OBJ_COMMIT, options);
        if (err)
                return err;
-       if (!get_commit_tree(commit)) {
-               err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", oid_to_hex(&tree_oid));
-               if (err)
-                       return err;
-       }
        if (memchr(buffer_begin, '\0', size)) {
-               err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
+               err = report(options, oid, OBJ_COMMIT, FSCK_MSG_NUL_IN_COMMIT,
                             "NUL byte in the commit object body");
                if (err)
                        return err;
@@ -868,91 +914,71 @@ static int fsck_commit_buffer(struct commit *commit, const char *buffer,
        return 0;
 }
 
-static int fsck_commit(struct commit *commit, const char *data,
-       unsigned long size, struct fsck_options *options)
+static int fsck_tag(const struct object_id *oid, const char *buffer,
+                   unsigned long size, struct fsck_options *options)
 {
-       const char *buffer = data ?  data : get_commit_buffer(commit, &size);
-       int ret = fsck_commit_buffer(commit, buffer, size, options);
-       if (!data)
-               unuse_commit_buffer(commit, buffer);
-       return ret;
+       struct object_id tagged_oid;
+       int tagged_type;
+       return fsck_tag_standalone(oid, buffer, size, options, &tagged_oid,
+                                  &tagged_type);
 }
 
-static int fsck_tag_buffer(struct tag *tag, const char *data,
-       unsigned long size, struct fsck_options *options)
+int fsck_tag_standalone(const struct object_id *oid, const char *buffer,
+                       unsigned long size, struct fsck_options *options,
+                       struct object_id *tagged_oid,
+                       int *tagged_type)
 {
-       struct object_id oid;
        int ret = 0;
-       const char *buffer;
-       char *to_free = NULL, *eol;
+       char *eol;
        struct strbuf sb = STRBUF_INIT;
        const char *p;
 
-       if (data)
-               buffer = data;
-       else {
-               enum object_type type;
-
-               buffer = to_free =
-                       read_object_file(&tag->object.oid, &type, &size);
-               if (!buffer)
-                       return report(options, &tag->object,
-                               FSCK_MSG_MISSING_TAG_OBJECT,
-                               "cannot read tag object");
-
-               if (type != OBJ_TAG) {
-                       ret = report(options, &tag->object,
-                               FSCK_MSG_TAG_OBJECT_NOT_TAG,
-                               "expected tag got %s",
-                           type_name(type));
-                       goto done;
-               }
-       }
-
-       ret = verify_headers(buffer, size, &tag->object, options);
+       ret = verify_headers(buffer, size, oid, OBJ_TAG, options);
        if (ret)
                goto done;
 
        if (!skip_prefix(buffer, "object ", &buffer)) {
-               ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
                goto done;
        }
-       if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
-               ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
+       if (parse_oid_hex(buffer, tagged_oid, &p) || *p != '\n') {
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
                if (ret)
                        goto done;
        }
        buffer = p + 1;
 
        if (!skip_prefix(buffer, "type ", &buffer)) {
-               ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
                goto done;
        }
        eol = strchr(buffer, '\n');
        if (!eol) {
-               ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
                goto done;
        }
-       if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
-               ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
+       *tagged_type = type_from_string_gently(buffer, eol - buffer, 1);
+       if (*tagged_type < 0)
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
        if (ret)
                goto done;
        buffer = eol + 1;
 
        if (!skip_prefix(buffer, "tag ", &buffer)) {
-               ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
                goto done;
        }
        eol = strchr(buffer, '\n');
        if (!eol) {
-               ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
                goto done;
        }
        strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
        if (check_refname_format(sb.buf, 0)) {
-               ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
-                          "invalid 'tag' name: %.*s",
-                          (int)(eol - buffer), buffer);
+               ret = report(options, oid, OBJ_TAG,
+                            FSCK_MSG_BAD_TAG_NAME,
+                            "invalid 'tag' name: %.*s",
+                            (int)(eol - buffer), buffer);
                if (ret)
                        goto done;
        }
@@ -960,30 +986,33 @@ static int fsck_tag_buffer(struct tag *tag, const char *data,
 
        if (!skip_prefix(buffer, "tagger ", &buffer)) {
                /* early tags do not contain 'tagger' lines; warn only */
-               ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
                if (ret)
                        goto done;
        }
        else
-               ret = fsck_ident(&buffer, &tag->object, options);
+               ret = fsck_ident(&buffer, oid, OBJ_TAG, options);
+       if (!*buffer)
+               goto done;
+
+       if (!starts_with(buffer, "\n")) {
+               /*
+                * The verify_headers() check will allow
+                * e.g. "[...]tagger <tagger>\nsome
+                * garbage\n\nmessage" to pass, thinking "some
+                * garbage" could be a custom header. E.g. "mktag"
+                * doesn't want any unknown headers.
+                */
+               ret = report(options, oid, OBJ_TAG, FSCK_MSG_EXTRA_HEADER_ENTRY, "invalid format - extra header(s) after 'tagger'");
+               if (ret)
+                       goto done;
+       }
 
 done:
        strbuf_release(&sb);
-       free(to_free);
        return ret;
 }
 
-static int fsck_tag(struct tag *tag, const char *data,
-       unsigned long size, struct fsck_options *options)
-{
-       struct object *tagged = tag->tagged;
-
-       if (!tagged)
-               return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
-
-       return fsck_tag_buffer(tag, data, size, options);
-}
-
 /*
  * Like builtin/submodule--helper.c's starts_with_dot_slash, but without
  * relying on the platform-dependent is_dir_sep helper.
@@ -1128,7 +1157,7 @@ static int check_submodule_url(const char *url)
 }
 
 struct fsck_gitmodules_data {
-       struct object *obj;
+       const struct object_id *oid;
        struct fsck_options *options;
        int ret;
 };
@@ -1137,7 +1166,7 @@ static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
 {
        struct fsck_gitmodules_data *data = vdata;
        const char *subsection, *key;
-       int subsection_len;
+       size_t subsection_len;
        char *name;
 
        if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
@@ -1146,25 +1175,28 @@ static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
 
        name = xmemdupz(subsection, subsection_len);
        if (check_submodule_name(name) < 0)
-               data->ret |= report(data->options, data->obj,
+               data->ret |= report(data->options,
+                                   data->oid, OBJ_BLOB,
                                    FSCK_MSG_GITMODULES_NAME,
                                    "disallowed submodule name: %s",
                                    name);
        if (!strcmp(key, "url") && value &&
            check_submodule_url(value) < 0)
-               data->ret |= report(data->options, data->obj,
+               data->ret |= report(data->options,
+                                   data->oid, OBJ_BLOB,
                                    FSCK_MSG_GITMODULES_URL,
                                    "disallowed submodule url: %s",
                                    value);
        if (!strcmp(key, "path") && value &&
            looks_like_command_line_option(value))
-               data->ret |= report(data->options, data->obj,
+               data->ret |= report(data->options,
+                                   data->oid, OBJ_BLOB,
                                    FSCK_MSG_GITMODULES_PATH,
                                    "disallowed submodule path: %s",
                                    value);
        if (!strcmp(key, "update") && value &&
            parse_submodule_update_type(value) == SM_UPDATE_COMMAND)
-               data->ret |= report(data->options, data->obj,
+               data->ret |= report(data->options, data->oid, OBJ_BLOB,
                                    FSCK_MSG_GITMODULES_UPDATE,
                                    "disallowed submodule update setting: %s",
                                    value);
@@ -1173,17 +1205,17 @@ static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
        return 0;
 }
 
-static int fsck_blob(struct blob *blob, const char *buf,
+static int fsck_blob(const struct object_id *oid, const char *buf,
                     unsigned long size, struct fsck_options *options)
 {
        struct fsck_gitmodules_data data;
        struct config_options config_opts = { 0 };
 
-       if (!oidset_contains(&gitmodules_found, &blob->object.oid))
+       if (!oidset_contains(&gitmodules_found, oid))
                return 0;
-       oidset_insert(&gitmodules_done, &blob->object.oid);
+       oidset_insert(&gitmodules_done, oid);
 
-       if (object_on_skiplist(options, &blob->object))
+       if (object_on_skiplist(options, oid))
                return 0;
 
        if (!buf) {
@@ -1192,18 +1224,18 @@ static int fsck_blob(struct blob *blob, const char *buf,
                 * blob too gigantic to load into memory. Let's just consider
                 * that an error.
                 */
-               return report(options, &blob->object,
+               return report(options, oid, OBJ_BLOB,
                              FSCK_MSG_GITMODULES_LARGE,
                              ".gitmodules too large to parse");
        }
 
-       data.obj = &blob->object;
+       data.oid = oid;
        data.options = options;
        data.ret = 0;
        config_opts.error_action = CONFIG_ERROR_SILENT;
        if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
                                ".gitmodules", buf, size, &data, &config_opts))
-               data.ret |= report(options, &blob->object,
+               data.ret |= report(options, oid, OBJ_BLOB,
                                   FSCK_MSG_GITMODULES_PARSE,
                                   "could not parse gitmodules blob");
 
@@ -1214,31 +1246,33 @@ int fsck_object(struct object *obj, void *data, unsigned long size,
        struct fsck_options *options)
 {
        if (!obj)
-               return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
+               return report(options, NULL, OBJ_NONE, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
 
        if (obj->type == OBJ_BLOB)
-               return fsck_blob((struct blob *)obj, data, size, options);
+               return fsck_blob(&obj->oid, data, size, options);
        if (obj->type == OBJ_TREE)
-               return fsck_tree((struct tree *) obj, options);
+               return fsck_tree(&obj->oid, data, size, options);
        if (obj->type == OBJ_COMMIT)
-               return fsck_commit((struct commit *) obj, (const char *) data,
-                       size, options);
+               return fsck_commit(&obj->oid, data, size, options);
        if (obj->type == OBJ_TAG)
-               return fsck_tag((struct tag *) obj, (const char *) data,
-                       size, options);
+               return fsck_tag(&obj->oid, data, size, options);
 
-       return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
-                         obj->type);
+       return report(options, &obj->oid, obj->type,
+                     FSCK_MSG_UNKNOWN_TYPE,
+                     "unknown type '%d' (internal fsck error)",
+                     obj->type);
 }
 
 int fsck_error_function(struct fsck_options *o,
-       struct object *obj, int msg_type, const char *message)
+                       const struct object_id *oid,
+                       enum object_type object_type,
+                       int msg_type, const char *message)
 {
        if (msg_type == FSCK_WARN) {
-               warning("object %s: %s", describe_object(o, obj), message);
+               warning("object %s: %s", fsck_describe_object(o, oid), message);
                return 0;
        }
-       error("object %s: %s", describe_object(o, obj), message);
+       error("object %s: %s", fsck_describe_object(o, oid), message);
        return 1;
 }
 
@@ -1250,7 +1284,6 @@ int fsck_finish(struct fsck_options *options)
 
        oidset_iter_init(&gitmodules_found, &iter);
        while ((oid = oidset_iter_next(&iter))) {
-               struct blob *blob;
                enum object_type type;
                unsigned long size;
                char *buf;
@@ -1258,29 +1291,22 @@ int fsck_finish(struct fsck_options *options)
                if (oidset_contains(&gitmodules_done, oid))
                        continue;
 
-               blob = lookup_blob(the_repository, oid);
-               if (!blob) {
-                       struct object *obj = lookup_unknown_object(oid->hash);
-                       ret |= report(options, obj,
-                                     FSCK_MSG_GITMODULES_BLOB,
-                                     "non-blob found at .gitmodules");
-                       continue;
-               }
-
                buf = read_object_file(oid, &type, &size);
                if (!buf) {
-                       if (is_promisor_object(&blob->object.oid))
+                       if (is_promisor_object(oid))
                                continue;
-                       ret |= report(options, &blob->object,
+                       ret |= report(options,
+                                     oid, OBJ_BLOB,
                                      FSCK_MSG_GITMODULES_MISSING,
                                      "unable to read .gitmodules blob");
                        continue;
                }
 
                if (type == OBJ_BLOB)
-                       ret |= fsck_blob(blob, buf, size, options);
+                       ret |= fsck_blob(oid, buf, size, options);
                else
-                       ret |= report(options, &blob->object,
+                       ret |= report(options,
+                                     oid, type,
                                      FSCK_MSG_GITMODULES_BLOB,
                                      "non-blob found at .gitmodules");
                free(buf);
@@ -1291,3 +1317,27 @@ int fsck_finish(struct fsck_options *options)
        oidset_clear(&gitmodules_done);
        return ret;
 }
+
+int fsck_config_internal(const char *var, const char *value, void *cb,
+                        struct fsck_options *options)
+{
+       if (strcmp(var, "fsck.skiplist") == 0) {
+               const char *path;
+               struct strbuf sb = STRBUF_INIT;
+
+               if (git_config_pathname(&path, var, value))
+                       return 1;
+               strbuf_addf(&sb, "skiplist=%s", path);
+               free((char *)path);
+               fsck_set_msg_types(options, sb.buf);
+               strbuf_release(&sb);
+               return 0;
+       }
+
+       if (skip_prefix(var, "fsck.", &var)) {
+               fsck_set_msg_type(options, var, value);
+               return 0;
+       }
+
+       return git_default_config(var, value, cb);
+}