[mutter] Add meta_display_set_alarm_filter()

[Owen Taylor <otaylor src gnome org>]

commit 44ecb1c050ddec57eebca79a4ec21ee480e6254a
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Thu Sep 11 10:09:43 2014 -0400

    Add meta_display_set_alarm_filter()
    
    Add a private hook for the test framework to get XSyncAlarmEvent events -
    this will be used to implement XSyncCounter based synchronization
    so that the test framework can deterministically wait until Mutter
    has seen actions performed by an X11 client.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=736505

 src/core/display-private.h |   11 +++++++++++
 src/core/display.c         |   11 +++++++++++
 src/x11/events.c           |    8 ++++++++
 3 files changed, 30 insertions(+), 0 deletions(-)
---
diff --git a/src/core/display-private.h b/src/core/display-private.h
index e63d22c..59ce085 100644
--- a/src/core/display-private.h
+++ b/src/core/display-private.h
@@ -97,6 +97,10 @@ typedef enum {
   META_EVENT_ROUTE_WINDOW_OP,
 } MetaEventRoute;
 
+typedef gboolean (*MetaAlarmFilter) (MetaDisplay           *display,
+                                     XSyncAlarmNotifyEvent *event,
+                                     gpointer               data);
+
 struct _MetaDisplay
 {
   GObject parent_instance;
@@ -256,6 +260,9 @@ struct _MetaDisplay
   MetaGestureTracker *gesture_tracker;
   ClutterEventSequence *pointer_emulating_sequence;
 
+  MetaAlarmFilter alarm_filter;
+  gpointer alarm_filter_data;
+
   int composite_event_base;
   int composite_error_base;
   int composite_major_version;
@@ -453,4 +460,8 @@ void meta_display_cancel_touch (MetaDisplay *display);
 
 gboolean meta_display_windows_are_interactable (MetaDisplay *display);
 
+gboolean meta_display_set_alarm_filter (MetaDisplay    *display,
+                                        MetaAlarmFilter filter,
+                                        gpointer        data);
+
 #endif
diff --git a/src/core/display.c b/src/core/display.c
index a6c5612..38630d6 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -2954,3 +2954,14 @@ meta_display_is_pointer_emulating_sequence (MetaDisplay          *display,
 
   return display->pointer_emulating_sequence == sequence;
 }
+
+gboolean
+meta_display_set_alarm_filter (MetaDisplay    *display,
+                               MetaAlarmFilter filter,
+                               gpointer        data)
+{
+  g_return_if_fail (filter == NULL || display->alarm_filter == NULL);
+
+  display->alarm_filter = filter;
+  display->alarm_filter_data = data;
+}
diff --git a/src/x11/events.c b/src/x11/events.c
index 19fbcaa..97bd41f 100644
--- a/src/x11/events.c
+++ b/src/x11/events.c
@@ -1188,6 +1188,14 @@ handle_other_xevent (MetaDisplay *display,
           meta_window_x11_update_sync_request_counter (alarm_window, new_counter_value);
           bypass_gtk = TRUE; /* GTK doesn't want to see this really */
         }
+      else
+        {
+          if (display->alarm_filter &&
+              display->alarm_filter (display,
+                                     (XSyncAlarmNotifyEvent*)event,
+                                     display->alarm_filter_data))
+            bypass_gtk = TRUE;
+        }
 
       goto out;
     }