[libnotify] Don't try to use the proxy after it is destroyed

[William Jon McCann <mccann src gnome org>]

commit d6476d362b807f8bf06e56cbe17d6b3c817e665e
Author: William Jon McCann <jmccann redhat com>
Date:   Thu Jun 24 01:42:18 2010 -0400

    Don't try to use the proxy after it is destroyed
    
    https://bugzilla.gnome.org/show_bug.cgi?id=608089

 libnotify/notification.c |   38 ++++++++++++++++++++++++++++++++++++--
 libnotify/notify.c       |   26 ++++++++++++++++++++++----
 2 files changed, 58 insertions(+), 6 deletions(-)
---
diff --git a/libnotify/notification.c b/libnotify/notification.c
index c992349..fa45c1e 100644
--- a/libnotify/notification.c
+++ b/libnotify/notification.c
@@ -404,7 +404,7 @@ notify_notification_finalize (GObject *object)
                 g_object_remove_weak_pointer (G_OBJECT (priv->status_icon),
                                               (gpointer) & priv->status_icon);
 
-        if (priv->signals_registered) {
+        if (proxy != NULL && priv->signals_registered) {
                 dbus_g_proxy_disconnect_signal (proxy,
                                                 "NotificationClosed",
                                                 G_CALLBACK (_close_signal_handler),
@@ -734,6 +734,24 @@ _gslist_to_string_array (GSList *list)
         return (char **) g_array_free (a, FALSE);
 }
 
+static void
+on_proxy_destroy (DBusGProxy         *proxy,
+                  NotifyNotification *notification)
+{
+        if (notification->priv->signals_registered) {
+                dbus_g_proxy_disconnect_signal (proxy,
+                                                "NotificationClosed",
+                                                G_CALLBACK (_close_signal_handler),
+                                                notification);
+                dbus_g_proxy_disconnect_signal (proxy,
+                                                "ActionInvoked",
+                                                G_CALLBACK (_action_signal_handler),
+                                                notification);
+                notification->priv->signals_registered = FALSE;
+        }
+}
+
+
 /**
  * notify_notification_show:
  * @notification: The notification.
@@ -759,8 +777,17 @@ notify_notification_show (NotifyNotification *notification,
 
         priv = notification->priv;
         proxy = _notify_get_g_proxy ();
+        if (proxy == NULL) {
+                g_set_error (error, 0, 0, "Unable to connect to server");
+                return FALSE;
+        }
 
         if (!priv->signals_registered) {
+                g_signal_connect (proxy,
+                                  "destroy",
+                                  G_CALLBACK (on_proxy_destroy),
+                                  notification);
+
                 dbus_g_proxy_connect_signal (proxy,
                                              "NotificationClosed",
                                              G_CALLBACK (_close_signal_handler),
@@ -1308,6 +1335,7 @@ notify_notification_close (NotifyNotification *notification,
 {
         NotifyNotificationPrivate *priv;
         GError         *tmp_error = NULL;
+        DBusGProxy     *proxy;
 
         g_return_val_if_fail (notification != NULL, FALSE);
         g_return_val_if_fail (NOTIFY_IS_NOTIFICATION (notification), FALSE);
@@ -1315,7 +1343,13 @@ notify_notification_close (NotifyNotification *notification,
 
         priv = notification->priv;
 
-        dbus_g_proxy_call (_notify_get_g_proxy (),
+        proxy = _notify_get_g_proxy ();
+        if (proxy == NULL) {
+                g_set_error (error, 0, 0, "Unable to connect to server");
+                return FALSE;
+        }
+
+        dbus_g_proxy_call (proxy,
                            "CloseNotification",
                            &tmp_error,
                            G_TYPE_UINT,
diff --git a/libnotify/notify.c b/libnotify/notify.c
index ccc3ed3..beba480 100644
--- a/libnotify/notify.c
+++ b/libnotify/notify.c
@@ -159,6 +159,13 @@ _notify_get_dbus_g_conn (void)
         return _dbus_gconn;
 }
 
+static void
+on_proxy_destroy (DBusGProxy *proxy,
+                  gpointer    data)
+{
+        _proxy = NULL;
+}
+
 DBusGProxy *
 _notify_get_g_proxy (void)
 {
@@ -183,6 +190,11 @@ _notify_get_g_proxy (void)
                                             NOTIFY_DBUS_CORE_INTERFACE);
         dbus_g_connection_unref (bus);
 
+        g_signal_connect (_proxy,
+                          "destroy",
+                          G_CALLBACK (on_proxy_destroy),
+                          NULL);
+
         dbus_g_object_register_marshaller (notify_marshal_VOID__UINT_UINT,
                                            G_TYPE_NONE,
                                            G_TYPE_UINT,
@@ -226,9 +238,12 @@ notify_get_server_caps (void)
         char          **caps = NULL;
         char          **cap;
         GList          *result = NULL;
-        DBusGProxy     *proxy = _notify_get_g_proxy ();
+        DBusGProxy     *proxy;
 
-        g_return_val_if_fail (proxy != NULL, NULL);
+        proxy = _notify_get_g_proxy ();
+        if (proxy == NULL) {
+                return NULL;
+        }
 
         if (!dbus_g_proxy_call (proxy,
                                 "GetCapabilities",
@@ -273,13 +288,16 @@ notify_get_server_info (char **ret_name,
                         char **ret_spec_version)
 {
         GError         *error = NULL;
-        DBusGProxy     *proxy = _notify_get_g_proxy ();
+        DBusGProxy     *proxy;
         char           *name;
         char           *vendor;
         char           *version;
         char           *spec_version;
 
-        g_return_val_if_fail (proxy != NULL, FALSE);
+        proxy = _notify_get_g_proxy ();
+        if (proxy == NULL) {
+                return FALSE;
+        }
 
         if (!dbus_g_proxy_call (proxy,
                                 "GetServerInformation",