+ is_different = 1;
+}
+
+static struct diff_options diff_opt = {
+ .recursive = 1,
+ .add_remove = file_add_remove,
+ .change = file_change,
+};
+
+static int same_tree(struct tree *t1, struct tree *t2)
+{
+ is_different = 0;
+ if (diff_tree_sha1(t1->object.sha1, t2->object.sha1, "", &diff_opt) < 0)
+ return 0;
+ return !is_different;
+}
+
+static int same_tree_as_empty(struct tree *t1)
+{
+ int retval;
+ void *tree;
+ struct tree_desc empty, real;
+
+ if (!t1)
+ return 0;
+
+ tree = read_object_with_reference(t1->object.sha1, "tree", &real.size, NULL);
+ if (!tree)
+ return 0;
+ real.buf = tree;
+
+ empty.buf = "";
+ empty.size = 0;
+
+ is_different = 0;
+ retval = diff_tree(&empty, &real, "", &diff_opt);
+ free(tree);
+
+ return retval >= 0 && !is_different;
+}
+
+static struct commit *try_to_simplify_merge(struct commit *commit, struct commit_list *parent)
+{
+ if (!commit->tree)
+ return NULL;
+
+ while (parent) {
+ struct commit *p = parent->item;
+ parent = parent->next;
+ parse_commit(p);
+ if (!p->tree)
+ continue;
+ if (same_tree(commit->tree, p->tree))
+ return p;
+ }
+ return NULL;
+}
+
+static void add_parents_to_list(struct commit *commit, struct commit_list **list)
+{
+ struct commit_list *parent = commit->parents;
+
+ /*
+ * If the commit is uninteresting, don't try to
+ * prune parents - we want the maximal uninteresting
+ * set.
+ *
+ * Normally we haven't parsed the parent
+ * yet, so we won't have a parent of a parent
+ * here. However, it may turn out that we've
+ * reached this commit some other way (where it
+ * wasn't uninteresting), in which case we need
+ * to mark its parents recursively too..
+ */
+ if (commit->object.flags & UNINTERESTING) {
+ while (parent) {
+ struct commit *p = parent->item;
+ parent = parent->next;
+ parse_commit(p);
+ p->object.flags |= UNINTERESTING;
+ if (p->parents)
+ mark_parents_uninteresting(p);
+ if (p->object.flags & SEEN)
+ continue;
+ p->object.flags |= SEEN;
+ insert_by_date(p, list);
+ }
+ return;
+ }
+
+ /*
+ * Ok, the commit wasn't uninteresting. If it
+ * is a merge, try to find the parent that has
+ * no differences in the path set if one exists.
+ */
+ if (paths && parent && parent->next) {
+ struct commit *preferred;
+
+ preferred = try_to_simplify_merge(commit, parent);
+ if (preferred) {
+ parent->item = preferred;
+ parent->next = NULL;
+ }
+ }
+
+ while (parent) {
+ struct commit *p = parent->item;
+
+ parent = parent->next;
+
+ parse_commit(p);
+ if (p->object.flags & SEEN)
+ continue;
+ p->object.flags |= SEEN;
+ insert_by_date(p, list);
+ }
+}
+
+static void compress_list(struct commit_list *list)
+{
+ while (list) {
+ struct commit *commit = list->item;
+ struct commit_list *parent = commit->parents;
+ list = list->next;
+
+ if (!parent) {
+ if (!same_tree_as_empty(commit->tree))
+ commit->object.flags |= TREECHANGE;
+ continue;
+ }
+
+ /*
+ * Exactly one parent? Check if it leaves the tree
+ * unchanged
+ */
+ if (!parent->next) {
+ struct tree *t1 = commit->tree;
+ struct tree *t2 = parent->item->tree;
+ if (!t1 || !t2 || same_tree(t1, t2))
+ continue;
+ }
+ commit->object.flags |= TREECHANGE;
+ }
+}
+
+static struct commit_list *limit_list(struct commit_list *list)
+{
+ struct commit_list *newlist = NULL;
+ struct commit_list **p = &newlist;
+ while (list) {
+ struct commit_list *entry = list;
+ struct commit *commit = list->item;
+ struct object *obj = &commit->object;
+
+ list = list->next;
+ free(entry);
+
+ if (max_age != -1 && (commit->date < max_age))
+ obj->flags |= UNINTERESTING;
+ if (unpacked && has_sha1_pack(obj->sha1))
+ obj->flags |= UNINTERESTING;
+ add_parents_to_list(commit, &list);
+ if (obj->flags & UNINTERESTING) {
+ mark_parents_uninteresting(commit);
+ if (everybody_uninteresting(list))
+ break;
+ continue;
+ }
+ if (min_age != -1 && (commit->date > min_age))
+ continue;
+ p = &commit_list_insert(commit, p)->next;
+ }
+ if (tree_objects)
+ mark_edges_uninteresting(newlist);
+ if (paths && dense)
+ compress_list(newlist);
+ if (bisect_list)
+ newlist = find_bisection(newlist);
+ return newlist;
+}
+
+static void add_pending_object(struct object *obj, const char *name)
+{
+ add_object(obj, &pending_objects, name);
+}
+
+static struct commit *get_commit_reference(const char *name, const unsigned char *sha1, unsigned int flags)
+{
+ struct object *object;
+
+ object = parse_object(sha1);
+ if (!object)
+ die("bad object %s", name);
+
+ /*
+ * Tag object? Look what it points to..
+ */
+ while (object->type == tag_type) {
+ struct tag *tag = (struct tag *) object;
+ object->flags |= flags;
+ if (tag_objects && !(object->flags & UNINTERESTING))
+ add_pending_object(object, tag->tag);
+ object = parse_object(tag->tagged->sha1);
+ if (!object)
+ die("bad object %s", sha1_to_hex(tag->tagged->sha1));
+ }
+
+ /*
+ * Commit object? Just return it, we'll do all the complex
+ * reachability crud.
+ */
+ if (object->type == commit_type) {
+ struct commit *commit = (struct commit *)object;
+ object->flags |= flags;
+ if (parse_commit(commit) < 0)
+ die("unable to parse commit %s", name);
+ if (flags & UNINTERESTING)
+ mark_parents_uninteresting(commit);
+ return commit;
+ }
+
+ /*
+ * Tree object? Either mark it uniniteresting, or add it
+ * to the list of objects to look at later..
+ */
+ if (object->type == tree_type) {
+ struct tree *tree = (struct tree *)object;
+ if (!tree_objects)
+ return NULL;
+ if (flags & UNINTERESTING) {
+ mark_tree_uninteresting(tree);
+ return NULL;
+ }
+ add_pending_object(object, "");
+ return NULL;
+ }
+
+ /*
+ * Blob object? You know the drill by now..
+ */
+ if (object->type == blob_type) {
+ struct blob *blob = (struct blob *)object;
+ if (!blob_objects)
+ return NULL;
+ if (flags & UNINTERESTING) {
+ mark_blob_uninteresting(blob);
+ return NULL;
+ }
+ add_pending_object(object, "");
+ return NULL;
+ }
+ die("%s is unknown object", name);
+}
+
+static void handle_one_commit(struct commit *com, struct commit_list **lst)
+{
+ if (!com || com->object.flags & SEEN)
+ return;
+ com->object.flags |= SEEN;
+ commit_list_insert(com, lst);
+}
+
+/* for_each_ref() callback does not allow user data -- Yuck. */
+static struct commit_list **global_lst;
+
+static int include_one_commit(const char *path, const unsigned char *sha1)
+{
+ struct commit *com = get_commit_reference(path, sha1, 0);
+ handle_one_commit(com, global_lst);
+ return 0;
+}
+
+static void handle_all(struct commit_list **lst)
+{
+ global_lst = lst;
+ for_each_ref(include_one_commit);
+ global_lst = NULL;
+}
+
+int main(int argc, const char **argv)
+{
+ const char *prefix = setup_git_directory();