swayidle: fix dbus_event not to block

swayidle/main.c

@@ -43,6 +43,12 @@ struct swayidle_timeout_cmd {
 	char *resume_cmd;
 };
 
+void sway_terminate(int exit_code) {
+	wl_display_disconnect(state.display);
+	wl_event_loop_destroy(state.event_loop);
+	exit(exit_code);
+}
+
 static void cmd_exec(char *param) {
 	wlr_log(WLR_DEBUG, "Cmd exec %s", param);
 	pid_t pid = fork();
@@ -138,10 +144,28 @@ static int prepare_for_sleep(sd_bus_message *msg, void *userdata,
 
 static int dbus_event(int fd, uint32_t mask, void *data) {
 	sd_bus *bus = data;
-	while (sd_bus_process(bus, NULL) > 0) {
-		// Do nothing.
+
+	if ((mask & WL_EVENT_HANGUP) || (mask & WL_EVENT_ERROR)) {
+		sway_terminate(0);
+	}
+
+	int count = 0;
+	if (mask & WL_EVENT_READABLE) {
+		count = sd_bus_process(bus, NULL);
+	}
+	if (mask & WL_EVENT_WRITABLE) {
+		sd_bus_flush(bus);
 	}
-	return 1;
+	if (mask == 0) {
+		sd_bus_flush(bus);
+	}
+
+	if (count < 0) {
+		wlr_log_errno(WLR_ERROR, "sd_bus_process failed, exiting");
+		sway_terminate(0);
+	}
+
+	return count;
 }
 
 static void setup_sleep_listener(void) {
@@ -167,8 +191,10 @@ static void setup_sleep_listener(void) {
 	}
 	acquire_sleep_lock();
 
-	wl_event_loop_add_fd(state.event_loop, sd_bus_get_fd(bus),
-			WL_EVENT_READABLE, dbus_event, bus);
+	struct wl_event_source *source = wl_event_loop_add_fd(state.event_loop,
+		sd_bus_get_fd(bus), WL_EVENT_READABLE | WL_EVENT_WRITABLE,
+		dbus_event, bus);
+	wl_event_source_check(source);
 }
 #endif
 
@@ -340,12 +366,6 @@ static int parse_args(int argc, char *argv[]) {
 	return 0;
 }
 
-void sway_terminate(int exit_code) {
-	wl_display_disconnect(state.display);
-	wl_event_loop_destroy(state.event_loop);
-	exit(exit_code);
-}
-
 static void register_zero_idle_timeout(void *item) {
 	struct swayidle_timeout_cmd *cmd = item;
 	register_timeout(cmd, 0);