[PATCH 10/15] sequencer: lib'ify save_head()

@@ -844,18 +844,22 @@ static int create_seq_dir(void)
 	return 0;
 }
 
-static void save_head(const char *head)
+static int save_head(const char *head)
 {
 	static struct lock_file head_lock;
 	struct strbuf buf = STRBUF_INIT;
 	int fd;
 
-	fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), LOCK_DIE_ON_ERROR);
+	fd = hold_lock_file_for_update(&head_lock, git_path_head_file(), 0);
+	if (fd < 0)
+		return error_errno(_("Could not lock HEAD"));
 	strbuf_addf(&buf, "%s\n", head);
 	if (write_in_full(fd, buf.buf, buf.len) < 0)
-		die_errno(_("Could not write to %s"), git_path_head_file());
+		return error_errno(_("Could not write to %s"),
+				   git_path_head_file());
 	if (commit_lock_file(&head_lock) < 0)
-		die(_("Error wrapping up %s."), git_path_head_file());
+		return error(_("Error wrapping up %s."), git_path_head_file());
+	return 0;
 }
 
 static int reset_for_rollback(const unsigned char *sha1)

@@ -1118,7 +1122,8 @@ int sequencer_pick_revisions(struct replay_opts *opts)
 		return -1;
 	if (get_sha1("HEAD", sha1) && (opts->action == REPLAY_REVERT))
 		return error(_("Can't revert as initial commit"));
-	save_head(sha1_to_hex(sha1));
+	if (save_head(sha1_to_hex(sha1)))
+		return -1;
 	save_opts(opts);
 	return pick_commits(todo_list, opts);
 }