[mutter] compositor: Add an API to focus the stage X window

[Jasper St. Pierre <jstpierre src gnome org>]

commit bd19de94292b3db7902c09ba16f5ba35c92a09d5
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Thu May 23 16:21:24 2013 -0400

    compositor: Add an API to focus the stage X window
    
    gnome-shell has traditionally just called XSetInputFocus when wanting to
    set the input focus to the stage window, but this might cause strange,
    hard-to-reproduce bugs because of an interference with mutter's focus
    prediction. Add API to allow gnome-shell to focus the stage window that
    also updates mutter's internal focus prediction state.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=700735

 src/compositor/compositor.c  |   22 ++++++++++++++++++++++
 src/core/display-private.h   |    5 +++++
 src/core/display.c           |   12 ++++++++++++
 src/meta/compositor-mutter.h |    2 ++
 4 files changed, 41 insertions(+), 0 deletions(-)
---
diff --git a/src/compositor/compositor.c b/src/compositor/compositor.c
index 86abfaf..40b9854 100644
--- a/src/compositor/compositor.c
+++ b/src/compositor/compositor.c
@@ -369,6 +369,28 @@ meta_empty_stage_input_region (MetaScreen *screen)
   meta_set_stage_input_region (screen, region);
 }
 
+void
+meta_focus_stage_window (MetaScreen *screen,
+                         guint32     timestamp)
+{
+  ClutterStage *stage;
+  Window window;
+
+  stage = CLUTTER_STAGE (meta_get_stage_for_screen (screen));
+  if (!stage)
+    return;
+
+  window = clutter_x11_get_stage_window (stage);
+
+  if (window == None)
+    return;
+
+  meta_display_set_input_focus_xwindow (screen->display,
+                                        screen,
+                                        window,
+                                        timestamp);
+}
+
 gboolean
 meta_begin_modal_for_plugin (MetaScreen       *screen,
                              MetaPlugin       *plugin,
diff --git a/src/core/display-private.h b/src/core/display-private.h
index 3415c84..c9a7d23 100644
--- a/src/core/display-private.h
+++ b/src/core/display-private.h
@@ -465,4 +465,9 @@ gboolean meta_display_process_barrier_event (MetaDisplay    *display,
                                              XIBarrierEvent *event);
 #endif /* HAVE_XI23 */
 
+void meta_display_set_input_focus_xwindow (MetaDisplay *display,
+                                           MetaScreen  *screen,
+                                           Window       window,
+                                           guint32      timestamp);
+
 #endif
diff --git a/src/core/display.c b/src/core/display.c
index 242d539..aa3338a 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -5807,6 +5807,18 @@ meta_display_request_take_focus (MetaDisplay *display,
 }
 
 void
+meta_display_set_input_focus_xwindow (MetaDisplay *display,
+                                      MetaScreen  *screen,
+                                      Window       window,
+                                      guint32      timestamp)
+{
+  request_xserver_input_focus_change (display,
+                                      screen,
+                                      window,
+                                      timestamp);
+}
+
+void
 meta_display_focus_the_no_focus_window (MetaDisplay *display,
                                         MetaScreen  *screen,
                                         guint32      timestamp)
diff --git a/src/meta/compositor-mutter.h b/src/meta/compositor-mutter.h
index 357b42e..698f8de 100644
--- a/src/meta/compositor-mutter.h
+++ b/src/meta/compositor-mutter.h
@@ -46,5 +46,7 @@ void        meta_enable_unredirect_for_screen   (MetaScreen *screen);
 void meta_set_stage_input_region     (MetaScreen    *screen,
                                       XserverRegion  region);
 void meta_empty_stage_input_region   (MetaScreen    *screen);
+void meta_focus_stage_window         (MetaScreen    *screen,
+                                      guint32        timestamp);
 
 #endif