+struct commit *lookup_commit_reference_by_name(const char *name)
+{
+ unsigned char sha1[20];
+ struct commit *commit;
+
+ if (get_sha1(name, sha1))
+ return NULL;
+ commit = lookup_commit_reference(sha1);
+ if (!commit || parse_commit(commit))
+ return NULL;
+ return commit;
+}
+