From 29952dee19c030d2ae1034e0304de72a645b4444 Mon Sep 17 00:00:00 2001
From: emersion <contact@emersion.fr>
Date: Wed, 30 Jan 2019 14:23:00 +0100
Subject: [PATCH] data-device: only allow one drag at a time

---
 types/data_device/wlr_drag.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/types/data_device/wlr_drag.c b/types/data_device/wlr_drag.c
index 20c9b30e..9bd63d96 100644
--- a/types/data_device/wlr_drag.c
+++ b/types/data_device/wlr_drag.c
@@ -122,6 +122,9 @@ static void drag_end(struct wlr_drag *drag) {
 			drag_icon_set_mapped(drag->icon, false);
 		}
 
+		assert(drag->seat->drag == drag);
+		drag->seat->drag = NULL;
+
 		wlr_signal_emit_safe(&drag->events.destroy, drag);
 		free(drag);
 	}
@@ -434,6 +437,13 @@ bool seat_client_start_drag(struct wlr_seat_client *client,
 		return true;
 	}
 
+	if (seat->drag != NULL) {
+		wlr_log(WLR_DEBUG, "Refusing to start drag, "
+			"another drag is already in progress");
+		free(drag);
+		return true;
+	}
+
 	if (icon_surface) {
 		int32_t touch_id = (point ? point->touch_id : 0);
 		struct wlr_drag_icon *icon =