From 6371f0c6219f75d2f56d1b1d140505d4d70da459 Mon Sep 17 00:00:00 2001
From: Matthew Allum <mallum@openedhand.com>
Date: Wed, 25 Jun 2008 12:02:11 +0000
Subject: [PATCH] 2008-06-25  Matthew Allum  <mallum@openedhand.com>

        * clutter/x11/clutter-backend-x11.c: (_clutter_x11_register_xinput)
        Add extra safety and fallback if no useable pointing devices are
        found.
---
 ChangeLog                         |  6 ++++++
 clutter/x11/clutter-backend-x11.c | 24 ++++++++++++++++++++++--
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1bed62278..54dbc97b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2008-06-25  Matthew Allum  <mallum@openedhand.com>
+
+	* clutter/x11/clutter-backend-x11.c: (_clutter_x11_register_xinput)
+        Add extra safety and fallback if no useable pointing devices are
+        found.
+
 2008-06-25  Emmanuele Bassi  <ebassi@openedhand.com>
 
 	* clutter/clutter-stage.c:
diff --git a/clutter/x11/clutter-backend-x11.c b/clutter/x11/clutter-backend-x11.c
index 1790222e2..2f4d7bd48 100644
--- a/clutter/x11/clutter-backend-x11.c
+++ b/clutter/x11/clutter-backend-x11.c
@@ -568,7 +568,8 @@ _clutter_x11_register_xinput ()
   gint num_devices = 0;
   gint num_events = 0;
   gint i = 0, j = 0;
-
+  gboolean have_an_xpointer = FALSE;
+  
   ClutterBackendX11      *x11b;
   ClutterX11XInputDevice *device = NULL;
 
@@ -617,11 +618,15 @@ _clutter_x11_register_xinput ()
         info->use == IsXExtensionKeyboard ||
         info->use == IsXExtensionDevice)
     {
+      clutter_x11_trap_x_errors ();
+      xdevice = XOpenDevice (x11b->xdpy, info->id);
+      if (clutter_x11_untrap_x_errors () || xdevice == NULL)
+        continue;
+
       /* Create the appropriate Clutter device */
       device = g_new0 (ClutterX11XInputDevice, 1);
       context->input_devices = g_slist_append (context->input_devices, device);
 
-      xdevice = XOpenDevice (x11b->xdpy, info->id);
       device->device.id = info->id;
 
       /* FIXME: some kind of general device_init() call should do below */
@@ -638,6 +643,7 @@ _clutter_x11_register_xinput ()
       {
         case IsXExtensionPointer:
           device->type = CLUTTER_X11_XINPUT_POINTER_DEVICE;
+          have_an_xpointer = TRUE;
           break;
         case IsXExtensionKeyboard:
           device->type = CLUTTER_X11_XINPUT_KEYBOARD_DEVICE;
@@ -694,11 +700,25 @@ _clutter_x11_register_xinput ()
         }
       }
 
+      if (info->use == IsXExtensionPointer && num_events > 0)
+        have_an_xpointer = TRUE;
+
       device->num_events  = num_events;
     }
   }
 
   XFree (xdevices);
+
+  if (!have_an_xpointer)
+    {
+      /* Something is likely wrong with Xinput setup so we basically
+       * abort here and fall back to lofi regular xinput.
+      */
+      g_warning ("No usuable XInput pointing devices found");
+      backend_singleton->have_xinput = FALSE;
+      g_slist_free (context->input_devices);
+      context->input_devices = NULL;
+    }
 }
 
 void