[PATCH xserver v2] xwayland: clear cursor frame callback

[Olivier Fourdan]

After an X cursor is unrealized, the seat's corresponding x_cursor is
cleared, but if a frame callback was pending at the time, it will
remain and thus prevent any further cursor update, leaving the window
with no cursor.

Make sure to destroy the frame callback, if any, when that occurs, so
that next time a cursor needs to be set, it won't be ignored for a frame
callback that will never be triggered.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1389327
Signed-off-by: Olivier Fourdan <ofourdan at redhat.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
---
 v2: Rename cursor_frame_callback() to clear_cursor_frame_callback()
     Add Pekka's r-b

 hw/xwayland/xwayland-cursor.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/hw/xwayland/xwayland-cursor.c b/hw/xwayland/xwayland-cursor.c
index 0c1cd34..f334f1c 100644
--- a/hw/xwayland/xwayland-cursor.c
+++ b/hw/xwayland/xwayland-cursor.c
@@ -96,14 +96,22 @@ xwl_unrealize_cursor(DeviceIntPtr device, ScreenPtr screen, CursorPtr cursor)
 }
 
 static void
+clear_cursor_frame_callback(struct xwl_seat *xwl_seat)
+{
+   if (xwl_seat->cursor_frame_cb) {
+       wl_callback_destroy (xwl_seat->cursor_frame_cb);
+       xwl_seat->cursor_frame_cb = NULL;
+   }
+}
+
+static void
 frame_callback(void *data,
                struct wl_callback *callback,
                uint32_t time)
 {
     struct xwl_seat *xwl_seat = data;
 
-    wl_callback_destroy (xwl_seat->cursor_frame_cb);
-    xwl_seat->cursor_frame_cb = NULL;
+    clear_cursor_frame_callback(xwl_seat);
     if (xwl_seat->cursor_needs_update) {
         xwl_seat->cursor_needs_update = FALSE;
         xwl_seat_set_cursor(xwl_seat);
@@ -127,6 +135,8 @@ xwl_seat_set_cursor(struct xwl_seat *xwl_seat)
     if (!xwl_seat->x_cursor) {
         wl_pointer_set_cursor(xwl_seat->wl_pointer,
                               xwl_seat->pointer_enter_serial, NULL, 0, 0);
+        clear_cursor_frame_callback(xwl_seat);
+        xwl_seat->cursor_needs_update = FALSE;
         return;
     }
 
-- 
2.9.3