[gtk+] wayland: Throttle system bell requests

[Jonas Ådahl <jadahl src gnome org>]

commit f6dd1f6ceb12baa6aef8c8585e959eec75a4cd7d
Author: Jonas Ådahl <jadahl gmail com>
Date:   Mon Mar 13 14:42:38 2017 +0800

    wayland: Throttle system bell requests
    
    If a bad behaving application tries to make the window/display beep too
    often, throttle the beep requests so that we don't end up filling the
    Wayland socket queue.
    
    The throttle is set to 50 beeps per second, which far more beeps than
    will ever make any sense from a user experience point of view, but will
    avoid terminating due to an excessive amount of requests.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=778188

 gdk/wayland/gdkdisplay-wayland.c |    9 +++++++++
 gdk/wayland/gdkdisplay-wayland.h |    2 ++
 2 files changed, 11 insertions(+), 0 deletions(-)
---
diff --git a/gdk/wayland/gdkdisplay-wayland.c b/gdk/wayland/gdkdisplay-wayland.c
index 0cca86c..0baa2de 100644
--- a/gdk/wayland/gdkdisplay-wayland.c
+++ b/gdk/wayland/gdkdisplay-wayland.c
@@ -83,6 +83,8 @@
  * ]|
  */
 
+#define MIN_SYSTEM_BELL_DELAY_MS 20
+
 static void _gdk_wayland_display_load_cursor_theme (GdkWaylandDisplay *display_wayland);
 
 G_DEFINE_TYPE (GdkWaylandDisplay, gdk_wayland_display, GDK_TYPE_DISPLAY)
@@ -666,6 +668,7 @@ gdk_wayland_display_system_bell (GdkDisplay *display,
 {
   GdkWaylandDisplay *display_wayland;
   struct gtk_surface1 *gtk_surface;
+  gint64 now_ms;
 
   g_return_if_fail (GDK_IS_DISPLAY (display));
 
@@ -679,6 +682,12 @@ gdk_wayland_display_system_bell (GdkDisplay *display,
   else
     gtk_surface = NULL;
 
+  now_ms = g_get_monotonic_time () / 1000;
+  if (now_ms - display_wayland->last_bell_time_ms < MIN_SYSTEM_BELL_DELAY_MS)
+    return;
+
+  display_wayland->last_bell_time_ms = now_ms;
+
   gtk_shell1_system_bell (display_wayland->gtk_shell, gtk_surface);
 }
 
diff --git a/gdk/wayland/gdkdisplay-wayland.h b/gdk/wayland/gdkdisplay-wayland.h
index a68940f..1270405 100644
--- a/gdk/wayland/gdkdisplay-wayland.h
+++ b/gdk/wayland/gdkdisplay-wayland.h
@@ -110,6 +110,8 @@ struct _GdkWaylandDisplay
 
   GPtrArray *monitors;
 
+  gint64 last_bell_time_ms;
+
   /* egl info */
   EGLDisplay egl_display;
   int egl_major_version;