[sabayon] Monitor the creation of the Xephyr window and send events to it

[Federico Mena Quintero <federico src gnome org>]

commit f61a4f5ea8e318af4994b397ac491b2befced84f
Author: Federico Mena Quintero <federico novell com>
Date:   Tue Jul 28 14:47:25 2009 -0500

    Monitor the creation of the Xephyr window and send events to it
    
    While 'Xnest -parent XID' uses the specified window to draw on, the same option
    in Xephyr makes it create a subwindow under the specified window.  So, we can no
    longer simply forward events to the XID window; we must send them to the subwindow
    which Xephyr creates.
    
    So, we catch CreateNotify events under our parent window to see when Xephyr creates
    its own subwindow.  We forward events to that window instead.
    
    Signed-off-by: Federico Mena Quintero <federico novell com>

 admin-tool/sessionwidget.py |   68 ++++++++++++++++++++++++++++++++----------
 1 files changed, 52 insertions(+), 16 deletions(-)
---
diff --git a/admin-tool/sessionwidget.py b/admin-tool/sessionwidget.py
index 55f95a5..a7b8cbf 100755
--- a/admin-tool/sessionwidget.py
+++ b/admin-tool/sessionwidget.py
@@ -26,6 +26,14 @@ import debuglog
 def dprint (fmt, *args):
     debuglog.debug_log (False, debuglog.DEBUG_LOG_DOMAIN_SESSION_WIDGET, fmt % args)
     
+def session_window_subwindow_created_cb (xid, user_data):
+    self = user_data
+
+    dprint ("subwindow got created with xid %x", xid)
+
+    self.xephyr_window = gtk.gdk.window_foreign_new_for_display (gtk.gdk.display_get_default (), xid)
+    dprint ("gdk foreign window created, %s", self.xephyr_window)
+
 class SessionWidget (gtk.Widget):
     # FIXME:
     #   Should be able override do_size_allocate() without this
@@ -41,6 +49,8 @@ class SessionWidget (gtk.Widget):
         self.session_width  = session_width
         self.session_height = session_height
 
+        self.xephyr_window = None
+
     def do_size_request (self, requisition):
         focus_width = self.style_get_property ("focus-line-width")
         focus_pad   = self.style_get_property ("focus-padding")
@@ -86,8 +96,27 @@ class SessionWidget (gtk.Widget):
                                               wclass = gtk.gdk.INPUT_OUTPUT,
                                               visual = self.get_visual (),
                                               colormap = self.get_colormap (),
-                                              event_mask = gtk.gdk.BUTTON_RELEASE_MASK)
+                                              event_mask = gtk.gdk.BUTTON_RELEASE_MASK | gtk.gdk.SUBSTRUCTURE_MASK)
         self.session_window.set_user_data (self)
+        dprint ("session window has xid %x", self.session_window.xid)
+
+        # We use Xephyr's "-parent" option to tell it where to create
+        # its window.  However, Xephyr does not use our window
+        # directly for drawing.  Instead, it creates a subwindow in
+        # our parent window, and uses *that*.  So, the events that we
+        # proxy to Xephyr must be sent to the window that it creates.
+        #
+        # To get notified when Xephyr creates its window inside ours,
+        # we select for gtk.gdk.SUBSTRUCTURE_MASK above.  However,
+        # there's no GDK_* event for CreateNotify events.  In an ideal
+        # world, we could just install a window event filter to
+        # extract that event ourselves.
+        #
+        # However, PyGTK is buggy and doesn't implement
+        # gdk_window_add_filter() correctly (see
+        # http://bugzilla.gnome.org/show_bug.cgi?id=156948).  So, we
+        # use our own wrapper for that function...
+        xlib.window_capture_create_notify (self.session_window, session_window_subwindow_created_cb, self)
 
         event_mask = gtk.gdk.BUTTON_PRESS_MASK   | \
                      gtk.gdk.BUTTON_RELEASE_MASK | \
@@ -95,7 +124,7 @@ class SessionWidget (gtk.Widget):
                      gtk.gdk.ENTER_NOTIFY_MASK   | \
                      gtk.gdk.LEAVE_NOTIFY_MASK   | \
                      gtk.gdk.KEY_PRESS_MASK      | \
-                     gtk.gdk.KEY_RELEASE_MASK;
+                     gtk.gdk.KEY_RELEASE_MASK
 
         self.input_window = gtk.gdk.Window (parent = self.get_parent_window (),
                                             window_type = gtk.gdk.WINDOW_CHILD,
@@ -177,50 +206,57 @@ class SessionWidget (gtk.Widget):
             self.grab_focus ()
             
         if not event.send_event:
-            dprint ("Resending button press; button = %d, state = 0x%x", event.button, event.state);
-            xlib.send_button_event (self.session_window, True, event.time, event.button, event.state);
+            if self.xephyr_window:
+                dprint ("Resending button press; button = %d, state = 0x%x", event.button, event.state)
+                xlib.send_button_event (self.xephyr_window, True, event.time, event.button, event.state)
         
         return True
     
     def do_button_release_event (self, event):
         if not event.send_event:
-            dprint ("Resending button release; button = %d, state = 0x%x", event.button, event.state);
-            xlib.send_button_event (self.session_window, False, event.time, event.button, event.state);
+            if self.xephyr_window:
+                dprint ("Resending button release; button = %d, state = 0x%x", event.button, event.state)
+                xlib.send_button_event (self.xephyr_window, False, event.time, event.button, event.state)
         
         return True
 
     def do_motion_notify_event (self, event):
         if not event.send_event:
-            dprint ("Resending motion notify; x = %d, y = %d", event.x, event.y);
-            xlib.send_motion_event (self.session_window, event.time, event.x, event.y);
+            if self.xephyr_window:
+                dprint ("Resending motion notify; x = %d, y = %d", event.x, event.y)
+                xlib.send_motion_event (self.xephyr_window, event.time, event.x, event.y);
         
         return True
     
     def do_enter_notify_event (self, event):
         if not event.send_event:
-            dprint ("Resending enter notify; x = %d, y = %d, detail = %d", event.x, event.y, event.detail);
-            xlib.send_crossing_event (self.session_window, True, event.time, event.x, event.y, event.detail);
+            if self.xephyr_window:
+                dprint ("Resending enter notify; x = %d, y = %d, detail = %d", event.x, event.y, event.detail)
+                xlib.send_crossing_event (self.xephyr_window, False, event.time, event.x, event.y, event.detail);
         
         return True
     
     def do_leave_notify_event (self, event):
         if not event.send_event:
-            dprint ("Resending leave notify; x = %d, y = %d, detail = %d", event.x, event.y, event.detail);
-            xlib.send_crossing_event (self.session_window, False, event.time, event.x, event.y, event.detail);
+            if self.xephyr_window:
+                dprint ("Resending leave notify; x = %d, y = %d, detail = %d", event.x, event.y, event.detail)
+                xlib.send_crossing_event (self.xephyr_window, False, event.time, event.x, event.y, event.detail);
         
         return True
     
     def do_key_press_event (self, event):
         if not event.send_event:
-            dprint ("Resending key press; keycode = 0x%x, state = 0x%x", event.hardware_keycode, event.state)
-            xlib.send_key_event (self.session_window, True, event.time, event.hardware_keycode, event.state)
+            if self.xephyr_window:
+                dprint ("Resending key press; keycode = 0x%x, state = 0x%x", event.hardware_keycode, event.state)
+                xlib.send_key_event (self.xephyr_window, True, event.time, event.hardware_keycode, event.state)
         
         return True
 
     def do_key_release_event (self, event):
         if not event.send_event:
-            dprint ("Resending key release; keycode = 0x%x, state = 0x%x", event.hardware_keycode, event.state)
-            xlib.send_key_event (self.session_window, False, event.time, event.hardware_keycode, event.state)
+            if self.xephyr_window:
+                dprint ("Resending key release; keycode = 0x%x, state = 0x%x", event.hardware_keycode, event.state)
+                xlib.send_key_event (self.xephyr_window, False, event.time, event.hardware_keycode, event.state)
         
         return True