diff --git a/commit.c b/commit.c
index eef1675..b01cc0c 100644
--- a/commit.c
+++ b/commit.c
@@ -209,14 +209,14 @@ static void prepare_commit_graft(struct repository *r)
 	r->parsed_objects->commit_graft_prepared = 1;
 }
 
-struct commit_graft *lookup_commit_graft_the_repository(const struct object_id *oid)
+struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid)
 {
 	int pos;
-	prepare_commit_graft(the_repository);
-	pos = commit_graft_pos(the_repository, oid->hash);
+	prepare_commit_graft(r);
+	pos = commit_graft_pos(r, oid->hash);
 	if (pos < 0)
 		return NULL;
-	return the_repository->parsed_objects->grafts[pos];
+	return r->parsed_objects->grafts[pos];
 }
 
 int for_each_commit_graft(each_commit_graft_fn fn, void *cb_data)
diff --git a/commit.h b/commit.h
index 45114a9..6de6f10 100644
--- a/commit.h
+++ b/commit.h
@@ -175,8 +175,7 @@ typedef int (*each_commit_graft_fn)(const struct commit_graft *, void *);
 
 struct commit_graft *read_graft_line(struct strbuf *line);
 int register_commit_graft(struct repository *r, struct commit_graft *, int);
-#define lookup_commit_graft(r, o) lookup_commit_graft_##r(o)
-struct commit_graft *lookup_commit_graft_the_repository(const struct object_id *oid);
+struct commit_graft *lookup_commit_graft(struct repository *r, const struct object_id *oid);
 
 extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2);
 extern struct commit_list *get_merge_bases_many(struct commit *one, int n, struct commit **twos);