[at-spi2-core] [registry] Fix crash handling DeregisterKeystrokeListener

[Mike Gorse <mgorse src gnome org>]

commit a15e79d744ce948a3765c8068da6d7c23da26880
Author: Mike Gorse <mgorse suse com>
Date:   Thu Nov 15 13:20:22 2012 -0600

    [registry] Fix crash handling DeregisterKeystrokeListener

 registryd/deviceeventcontroller.c |   30 ++++++++++++++++++++++++------
 1 files changed, 24 insertions(+), 6 deletions(-)
---
diff --git a/registryd/deviceeventcontroller.c b/registryd/deviceeventcontroller.c
index b8c1bc7..2d5a894 100644
--- a/registryd/deviceeventcontroller.c
+++ b/registryd/deviceeventcontroller.c
@@ -1041,12 +1041,25 @@ append_keystroke_listener (DBusMessageIter *iter, DEControllerKeyListener *liste
   if (dbus_message_iter_open_container (&iter_struct, DBUS_TYPE_STRUCT,
                                          NULL, &iter_substruct))
   {
-    dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
-                                    &listener->mode->synchronous);
-    dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
-                                    &listener->mode->preemptive);
-    dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
-                                    &listener->mode->global);
+    if (listener->mode)
+    {
+      dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
+                                      &listener->mode->synchronous);
+      dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
+                                      &listener->mode->preemptive);
+      dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
+                                      &listener->mode->global);
+    }
+    else
+    {
+      dbus_bool_t dummy_val = FALSE;
+      dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
+                                      &dummy_val);
+      dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
+                                      &dummy_val);
+      dbus_message_iter_append_basic (&iter_substruct, DBUS_TYPE_BOOLEAN,
+                                      &dummy_val);
+    }
     dbus_message_iter_close_container (&iter_struct, &iter_substruct);
   }
   dbus_message_iter_close_container (iter, &iter_struct);
@@ -2353,6 +2366,11 @@ impl_deregister_keystroke_listener (DBusConnection *bus,
 
   dbus_message_iter_init(message, &iter);
   if (strcmp (dbus_message_get_signature (message), "oa(iisi)uu") != 0)
+  {
+    g_warning ("Received DeregisterKeystrokeListener with strange signature '%s'", dbus_message_get_signature (message));
+    return invalid_arguments_error (message);
+  }
+
   dbus_message_iter_get_basic(&iter, &path);
   dbus_message_iter_next(&iter);
   dbus_message_iter_recurse(&iter, &iter_array);