diff --git a/revision.h b/revision.h
new file mode 100644
index 0000000..5170ac4
--- /dev/null
+++ b/revision.h
@@ -0,0 +1,48 @@
+#ifndef REVISION_H
+#define REVISION_H
+
+#define SEEN		(1u<<0)
+#define UNINTERESTING   (1u<<1)
+
+struct rev_info {
+	/* Starting list */
+	struct commit_list *commits;
+	struct object_list *pending_objects;
+
+	/* Basic information */
+	const char *prefix;
+	const char **paths;
+
+	/* Traversal flags */
+	unsigned int	dense:1,
+			remove_empty_trees:1,
+			lifo:1,
+			topo_order:1,
+			tag_objects:1,
+			tree_objects:1,
+			blob_objects:1,
+			edge_hint:1;
+
+	/* special limits */
+	int max_count;
+	unsigned long max_age;
+	unsigned long min_age;
+};
+
+/* revision.c */
+extern int setup_revisions(int argc, const char **argv, struct rev_info *revs);
+extern void mark_parents_uninteresting(struct commit *commit);
+extern void mark_tree_uninteresting(struct tree *tree);
+
+struct name_path {
+	struct name_path *up;
+	int elem_len;
+	const char *elem;
+};
+
+extern struct object_list **add_object(struct object *obj,
+				       struct object_list **p,
+				       struct name_path *path,
+				       const char *name);
+
+#endif