Wake up any clients waiting with the wait-for command when the server

exits.

cmd-wait-for.c

@@ -194,3 +194,25 @@ cmd_wait_for_unlock(struct cmd_q *cmdq, const char *name,
 	return (CMD_RETURN_NORMAL);
 }
 
+void
+cmd_wait_for_flush(void)
+{
+	struct wait_channel	*wc, *wc1;
+	struct cmd_q		*wq, *wq1;
+
+	RB_FOREACH_SAFE(wc, wait_channels, &wait_channels, wc1) {
+		TAILQ_FOREACH_SAFE(wq, &wc->waiters, waitentry, wq1) {
+			TAILQ_REMOVE(&wc->waiters, wq, waitentry);
+			if (!cmdq_free(wq))
+				cmdq_continue(wq);
+		}
+		while ((wq = TAILQ_FIRST(&wc->lockers)) != NULL) {
+			TAILQ_REMOVE(&wc->lockers, wq, waitentry);
+			if (!cmdq_free(wq))
+				cmdq_continue(wq);
+		}
+		RB_REMOVE(wait_channels, &wait_channels, wc);
+		free((void *)wc->name);
+		free(wc);
+	}
+}

server.c

@@ -217,16 +217,30 @@ server_loop(void)
 int
 server_should_shutdown(void)
 {
+	struct client	*c;
 	u_int		 i;
 
 	if (!options_get_number(&global_options, "exit-unattached")) {
 		if (!RB_EMPTY(&sessions))
 			return (0);
 	}
+
+	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
+		c = ARRAY_ITEM(&clients, i);
+		if (c != NULL && c->session != NULL)
+			return (0);
+	}
+
+	/*
+	 * No attached clients therefore want to exit - flush any waiting
+	 * clients but don't actually exit until they've gone.
+	 */
+	cmd_wait_for_flush();
 	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
 		if (ARRAY_ITEM(&clients, i) != NULL)
 			return (0);
 	}
+
 	return (1);
 }
 
@@ -238,6 +252,8 @@ server_send_shutdown(void)
 	struct session	*s, *next_s;
 	u_int		 i;
 
+	cmd_wait_for_flush();
+
 	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
 		c = ARRAY_ITEM(&clients, i);
 		if (c != NULL) {

tmux.h

@@ -1924,6 +1924,9 @@ void		 cmdq_flush(struct cmd_q *);
 int	cmd_string_parse(const char *, struct cmd_list **, const char *,
 	    u_int, char **);
 
+/* cmd-wait-for.c */
+void	cmd_wait_for_flush(void);
+
 /* client.c */
 int	client_main(int, char **, int);