Merge with trunk

14 files changed, 348 insertions, 136 deletions

diff --git a/src/greeter.c b/src/greeter.c
index e1d47f86..b9f4f55a 100644
--- a/src/greeter.c
+++ b/src/greeter.c
@@ -76,6 +76,8 @@ struct GreeterPrivate
     gboolean guest_account_authenticated;
 
     /* Communication channels to communicate with */
+    int to_greeter_input;
+    int from_greeter_output;
     GIOChannel *to_greeter_channel;
     GIOChannel *from_greeter_channel;
     guint from_greeter_watch;
@@ -954,6 +956,7 @@ greeter_start (Session *session)
 {
     Greeter *greeter = GREETER (session);
     int to_greeter_pipe[2], from_greeter_pipe[2];
+    int to_greeter_output, from_greeter_input;
     gboolean result = FALSE;
     gchar *value;
     GError *error = NULL;
@@ -964,12 +967,16 @@ greeter_start (Session *session)
         g_warning ("Failed to create pipes: %s", strerror (errno));
         return FALSE;
     }
-    greeter->priv->to_greeter_channel = g_io_channel_unix_new (to_greeter_pipe[1]);
+    to_greeter_output = to_greeter_pipe[0];
+    greeter->priv->to_greeter_input = to_greeter_pipe[1];
+    greeter->priv->to_greeter_channel = g_io_channel_unix_new (greeter->priv->to_greeter_input);
     g_io_channel_set_encoding (greeter->priv->to_greeter_channel, NULL, &error);
     if (error)
         g_warning ("Failed to set encoding on to greeter channel to binary: %s\n", error->message);
     g_clear_error (&error);
-    greeter->priv->from_greeter_channel = g_io_channel_unix_new (from_greeter_pipe[0]);
+    greeter->priv->from_greeter_output = from_greeter_pipe[0];
+    from_greeter_input = from_greeter_pipe[1];
+    greeter->priv->from_greeter_channel = g_io_channel_unix_new (greeter->priv->from_greeter_output);
     g_io_channel_set_encoding (greeter->priv->from_greeter_channel, NULL, &error);
     if (error)
         g_warning ("Failed to set encoding on from greeter channel to binary: %s\n", error->message);
@@ -978,22 +985,22 @@ greeter_start (Session *session)
     greeter->priv->from_greeter_watch = g_io_add_watch (greeter->priv->from_greeter_channel, G_IO_IN | G_IO_HUP, read_cb, greeter);
 
     /* Let the greeter session know how to communicate with the daemon */
-    value = g_strdup_printf ("%d", from_greeter_pipe[1]);
+    value = g_strdup_printf ("%d", from_greeter_input);
     session_set_env (SESSION (greeter), "LIGHTDM_TO_SERVER_FD", value);
     g_free (value);
-    value = g_strdup_printf ("%d", to_greeter_pipe[0]);
+    value = g_strdup_printf ("%d", to_greeter_output);
     session_set_env (SESSION (greeter), "LIGHTDM_FROM_SERVER_FD", value);
     g_free (value);
 
     /* Don't allow the daemon end of the pipes to be accessed in child processes */
-    fcntl (to_greeter_pipe[1], F_SETFD, FD_CLOEXEC);
-    fcntl (from_greeter_pipe[0], F_SETFD, FD_CLOEXEC);
+    fcntl (greeter->priv->to_greeter_input, F_SETFD, FD_CLOEXEC);
+    fcntl (greeter->priv->from_greeter_output, F_SETFD, FD_CLOEXEC);
 
     result = SESSION_CLASS (greeter_parent_class)->start (session);
 
     /* Close the session ends of the pipe */
-    close (to_greeter_pipe[0]);
-    close (from_greeter_pipe[1]);
+    close (to_greeter_output);
+    close (from_greeter_input);
 
     return result;
 }
@@ -1029,6 +1036,8 @@ greeter_init (Greeter *greeter)
     greeter->priv->read_buffer = secure_malloc (greeter, HEADER_SIZE);
     greeter->priv->hints = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
     greeter->priv->use_secure_memory = config_get_boolean (config_get_instance (), "LightDM", "lock-memory");
+    greeter->priv->to_greeter_input = -1;
+    greeter->priv->from_greeter_output = -1;
 }
 
 static void
@@ -1049,6 +1058,8 @@ greeter_finalize (GObject *object)
         g_signal_handlers_disconnect_matched (self->priv->authentication_session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
         g_object_unref (self->priv->authentication_session);
     }
+    close (self->priv->to_greeter_input);
+    close (self->priv->from_greeter_output);
     if (self->priv->to_greeter_channel)
         g_io_channel_unref (self->priv->to_greeter_channel);
     if (self->priv->from_greeter_channel)
diff --git a/src/lightdm.c b/src/lightdm.c
index f87df156..72f7eb0c 100644
--- a/src/lightdm.c
+++ b/src/lightdm.c
@@ -153,18 +153,16 @@ get_config_sections (const gchar *seat_name)
     gchar **groups, **i;
     GList *config_sections = NULL;
 
-    config_sections = g_list_append (config_sections, g_strdup ("SeatDefaults"));
-
-    if (!seat_name)
-        return config_sections;
+    /* Load seat defaults first */
+    config_sections = g_list_append (config_sections, g_strdup ("Seat:*"));
 
     groups = config_get_groups (config_get_instance ());
     for (i = groups; *i; i++)
     {
-        if (g_str_has_prefix (*i, "Seat:"))
+        if (g_str_has_prefix (*i, "Seat:") && strcmp (*i, "Seat:*") != 0)
         {
             const gchar *seat_name_glob = *i + strlen ("Seat:");
-            if (g_pattern_match_simple (seat_name_glob, seat_name))
+            if (g_pattern_match_simple (seat_name_glob, seat_name ? seat_name : ""))
                 config_sections = g_list_append (config_sections, g_strdup (*i));
         }
     }
@@ -184,8 +182,9 @@ set_seat_properties (Seat *seat, const gchar *seat_name)
     for (link = sections; link; link = link->next)
     {
         const gchar *section = link->data;
-        g_debug ("Loading properties from config section %s", section);
         keys = config_get_keys (config_get_instance (), section);
+
+        l_debug (seat, "Loading properties from config section %s", section);
         for (i = 0; keys && keys[i]; i++)
         {
             gchar *value = config_get_string (config_get_instance (), section, keys[i]);
@@ -611,11 +610,6 @@ seat_bus_entry_free (gpointer data)
 {
     SeatBusEntry *entry = data;
 
-    g_dbus_connection_unregister_object (bus, entry->bus_id);
-
-    emit_object_value_changed (bus, "/org/freedesktop/DisplayManager", "org.freedesktop.DisplayManager", "Seats", get_seat_list ());
-    emit_object_signal (bus, "/org/freedesktop/DisplayManager", "SeatRemoved", entry->path);
-
     g_free (entry->path);
     g_free (entry);
 }
@@ -625,14 +619,6 @@ session_bus_entry_free (gpointer data)
 {
     SessionBusEntry *entry = data;
 
-    g_dbus_connection_unregister_object (bus, entry->bus_id);
-
-    emit_object_value_changed (bus, "/org/freedesktop/DisplayManager", "org.freedesktop.DisplayManager", "Sessions", get_session_list (NULL));
-    emit_object_signal (bus, "/org/freedesktop/DisplayManager", "SessionRemoved", entry->path);
-
-    emit_object_value_changed (bus, entry->seat_path, "org.freedesktop.DisplayManager.Seat", "Sessions", get_session_list (entry->seat_path));
-    emit_object_signal (bus, entry->seat_path, "SessionRemoved", entry->path);
-
     g_free (entry->path);
     g_free (entry->seat_path);
     g_free (entry);
@@ -659,7 +645,6 @@ running_user_session_cb (Seat *seat, Session *session)
     session_set_env (session, "XDG_SESSION_PATH", path);
     g_object_set_data_full (G_OBJECT (session), "XDG_SESSION_PATH", path, g_free);
 
-    seat_entry = g_hash_table_lookup (seat_bus_entries, seat);
     session_entry = session_bus_entry_new (g_object_get_data (G_OBJECT (session), "XDG_SESSION_PATH"), seat_entry ? seat_entry->path : NULL);
     g_hash_table_insert (session_bus_entries, g_object_ref (session), session_entry);
 
@@ -685,8 +670,28 @@ running_user_session_cb (Seat *seat, Session *session)
 static void
 session_removed_cb (Seat *seat, Session *session)
 {
+    SessionBusEntry *entry;
+    gchar *seat_path = NULL;
+
     g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
+
+    entry = g_hash_table_lookup (session_bus_entries, session);
+    if (entry)
+    {
+        g_dbus_connection_unregister_object (bus, entry->bus_id);
+        emit_object_signal (bus, "/org/freedesktop/DisplayManager", "SessionRemoved", entry->path);
+        emit_object_signal (bus, entry->seat_path, "SessionRemoved", entry->path);
+        seat_path = g_strdup (entry->seat_path);
+    }
+
     g_hash_table_remove (session_bus_entries, session);
+
+    if (seat_path)
+    {
+        emit_object_value_changed (bus, "/org/freedesktop/DisplayManager", "org.freedesktop.DisplayManager", "Sessions", get_session_list (NULL));
+        emit_object_value_changed (bus, seat_path, "org.freedesktop.DisplayManager.Seat", "Sessions", get_session_list (seat_path));
+        g_free (seat_path);
+    }
 }
 
 static void
@@ -730,7 +735,18 @@ seat_added_cb (DisplayManager *display_manager, Seat *seat)
 static void
 seat_removed_cb (DisplayManager *display_manager, Seat *seat)
 {
+    SeatBusEntry *entry;
+
+    entry = g_hash_table_lookup (seat_bus_entries, seat);
+    if (entry)
+    {
+        g_dbus_connection_unregister_object (bus, entry->bus_id);
+        emit_object_signal (bus, "/org/freedesktop/DisplayManager", "SeatRemoved", entry->path);
+    }
+
     g_hash_table_remove (seat_bus_entries, seat);
+  
+    emit_object_value_changed (bus, "/org/freedesktop/DisplayManager", "org.freedesktop.DisplayManager", "Seats", get_seat_list ());
 }
 
 static gboolean
@@ -1068,6 +1084,48 @@ login1_can_graphical_changed_cb (Login1Seat *login1_seat)
 }
 
 static void
+login1_active_session_changed_cb (Login1Seat *login1_seat, const gchar *login1_session_id)
+{
+    g_debug ("Seat %s changes active session to %s", login1_seat_get_id (login1_seat), login1_session_id);
+
+    Seat *seat;
+    seat = display_manager_get_seat (display_manager, login1_seat_get_id (login1_seat));
+
+    if (seat)
+    {
+        Session *active_session;
+        active_session = seat_get_expected_active_session (seat);
+
+        if (g_strcmp0 (login1_session_id, session_get_login1_session_id (active_session)) == 0)
+        {
+            // Session is already active
+            g_debug ("Session %s is already active", login1_session_id);
+            return;
+        }
+
+        active_session = seat_find_session_by_login1_id (seat, login1_session_id);
+        if (active_session != NULL)
+        {
+            g_debug ("Activating session %s", login1_session_id);
+            seat_set_externally_activated_session (seat, active_session);
+            return;
+
+        }
+    }
+}
+
+static gboolean
+login1_add_seat (Login1Seat *login1_seat)
+{
+    if (config_get_boolean (config_get_instance (), "LightDM", "logind-check-graphical"))
+        g_signal_connect (login1_seat, "can-graphical-changed", G_CALLBACK (login1_can_graphical_changed_cb), NULL);
+
+    g_signal_connect (login1_seat, LOGIN1_SIGNAL_ACTIVE_SESION_CHANGED, G_CALLBACK (login1_active_session_changed_cb), NULL);
+
+    return update_login1_seat (login1_seat);
+}
+
+static void
 login1_service_seat_added_cb (Login1Service *service, Login1Seat *login1_seat)
 {
     if (login1_seat_get_can_graphical (login1_seat))
@@ -1075,9 +1133,7 @@ login1_service_seat_added_cb (Login1Service *service, Login1Seat *login1_seat)
     else
         g_debug ("Seat %s added from logind without graphical output", login1_seat_get_id (login1_seat));
 
-    if (config_get_boolean (config_get_instance (), "LightDM", "logind-check-graphical"))
-        g_signal_connect (login1_seat, LOGIN1_SEAT_SIGNAL_CAN_GRAPHICAL_CHANGED, G_CALLBACK (login1_can_graphical_changed_cb), NULL);
-    update_login1_seat (login1_seat);
+    login1_add_seat (login1_seat);
 }
 
 static void
@@ -1085,6 +1141,7 @@ login1_service_seat_removed_cb (Login1Service *service, Login1Seat *login1_seat)
 {
     g_debug ("Seat %s removed from logind", login1_seat_get_id (login1_seat));
     g_signal_handlers_disconnect_matched (login1_seat, G_SIGNAL_MATCH_FUNC, 0, 0, NULL, login1_can_graphical_changed_cb, NULL);
+    g_signal_handlers_disconnect_matched (login1_seat, G_SIGNAL_MATCH_FUNC, 0, 0, NULL, login1_active_session_changed_cb, NULL);
     remove_login1_seat (login1_seat);
 }
 
@@ -1319,36 +1376,38 @@ main (int argc, char **argv)
         config_set_string (config_get_instance (), "LightDM", "greeter-user", GREETER_USER);
     if (!config_has_key (config_get_instance (), "LightDM", "lock-memory"))
         config_set_boolean (config_get_instance (), "LightDM", "lock-memory", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "type"))
-        config_set_string (config_get_instance (), "SeatDefaults", "type", "xlocal");
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "pam-service"))
-        config_set_string (config_get_instance (), "SeatDefaults", "pam-service", "lightdm");
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "pam-autologin-service"))
-        config_set_string (config_get_instance (), "SeatDefaults", "pam-autologin-service", "lightdm-autologin");
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "pam-greeter-service"))
-        config_set_string (config_get_instance (), "SeatDefaults", "pam-greeter-service", "lightdm-greeter");
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "xserver-command"))
-        config_set_string (config_get_instance (), "SeatDefaults", "xserver-command", "X");
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "xserver-share"))
-        config_set_boolean (config_get_instance (), "SeatDefaults", "xserver-share", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "unity-compositor-command"))
-        config_set_string (config_get_instance (), "SeatDefaults", "unity-compositor-command", "unity-system-compositor");
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "start-session"))
-        config_set_boolean (config_get_instance (), "SeatDefaults", "start-session", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "allow-user-switching"))
-        config_set_boolean (config_get_instance (), "SeatDefaults", "allow-user-switching", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "allow-guest"))
-        config_set_boolean (config_get_instance (), "SeatDefaults", "allow-guest", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "greeter-allow-guest"))
-        config_set_boolean (config_get_instance (), "SeatDefaults", "greeter-allow-guest", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "greeter-show-remote-login"))
-        config_set_boolean (config_get_instance (), "SeatDefaults", "greeter-show-remote-login", TRUE);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "greeter-session"))
-        config_set_string (config_get_instance (), "SeatDefaults", "greeter-session", GREETER_SESSION);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "user-session"))
-        config_set_string (config_get_instance (), "SeatDefaults", "user-session", USER_SESSION);
-    if (!config_has_key (config_get_instance (), "SeatDefaults", "session-wrapper"))
-        config_set_string (config_get_instance (), "SeatDefaults", "session-wrapper", "lightdm-session");
+    if (!config_has_key (config_get_instance (), "Seat:*", "type"))
+        config_set_string (config_get_instance (), "Seat:*", "type", "xlocal");
+    if (!config_has_key (config_get_instance (), "Seat:*", "pam-service"))
+        config_set_string (config_get_instance (), "Seat:*", "pam-service", "lightdm");
+    if (!config_has_key (config_get_instance (), "Seat:*", "pam-autologin-service"))
+        config_set_string (config_get_instance (), "Seat:*", "pam-autologin-service", "lightdm-autologin");
+    if (!config_has_key (config_get_instance (), "Seat:*", "pam-greeter-service"))
+        config_set_string (config_get_instance (), "Seat:*", "pam-greeter-service", "lightdm-greeter");
+    if (!config_has_key (config_get_instance (), "Seat:*", "xserver-command"))
+        config_set_string (config_get_instance (), "Seat:*", "xserver-command", "X");
+    if (!config_has_key (config_get_instance (), "Seat:*", "xmir-command"))
+        config_set_string (config_get_instance (), "Seat:*", "xmir-command", "Xmir");
+    if (!config_has_key (config_get_instance (), "Seat:*", "xserver-share"))
+        config_set_boolean (config_get_instance (), "Seat:*", "xserver-share", TRUE);
+    if (!config_has_key (config_get_instance (), "Seat:*", "unity-compositor-command"))
+        config_set_string (config_get_instance (), "Seat:*", "unity-compositor-command", "unity-system-compositor");
+    if (!config_has_key (config_get_instance (), "Seat:*", "start-session"))
+        config_set_boolean (config_get_instance (), "Seat:*", "start-session", TRUE);
+    if (!config_has_key (config_get_instance (), "Seat:*", "allow-user-switching"))
+        config_set_boolean (config_get_instance (), "Seat:*", "allow-user-switching", TRUE);
+    if (!config_has_key (config_get_instance (), "Seat:*", "allow-guest"))
+        config_set_boolean (config_get_instance (), "Seat:*", "allow-guest", TRUE);
+    if (!config_has_key (config_get_instance (), "Seat:*", "greeter-allow-guest"))
+        config_set_boolean (config_get_instance (), "Seat:*", "greeter-allow-guest", TRUE);
+    if (!config_has_key (config_get_instance (), "Seat:*", "greeter-show-remote-login"))
+        config_set_boolean (config_get_instance (), "Seat:*", "greeter-show-remote-login", TRUE);
+    if (!config_has_key (config_get_instance (), "Seat:*", "greeter-session"))
+        config_set_string (config_get_instance (), "Seat:*", "greeter-session", GREETER_SESSION);
+    if (!config_has_key (config_get_instance (), "Seat:*", "user-session"))
+        config_set_string (config_get_instance (), "Seat:*", "user-session", USER_SESSION);
+    if (!config_has_key (config_get_instance (), "Seat:*", "session-wrapper"))
+        config_set_string (config_get_instance (), "Seat:*", "session-wrapper", "lightdm-session");
     if (!config_has_key (config_get_instance (), "LightDM", "log-directory"))
         config_set_string (config_get_instance (), "LightDM", "log-directory", default_log_dir);
     g_free (default_log_dir);
@@ -1432,9 +1491,7 @@ main (int argc, char **argv)
             for (link = login1_service_get_seats (login1_service_get_instance ()); link; link = link->next)
             {
                 Login1Seat *login1_seat = link->data;
-                if (config_get_boolean (config_get_instance (), "LightDM", "logind-check-graphical"))
-                    g_signal_connect (login1_seat, LOGIN1_SEAT_SIGNAL_CAN_GRAPHICAL_CHANGED, G_CALLBACK (login1_can_graphical_changed_cb), NULL);
-                if (!update_login1_seat (login1_seat))
+                if (!login1_add_seat (login1_seat))
                     return EXIT_FAILURE;
             }
         }
@@ -1449,7 +1506,7 @@ main (int argc, char **argv)
 
             g_debug ("Adding default seat");
 
-            types = config_get_string_list (config_get_instance (), "SeatDefaults", "type");
+            types = config_get_string_list (config_get_instance (), "Seat:*", "type");
             for (type = types; type && *type; type++)
             {
                 seat = seat_new (*type, "seat0");
diff --git a/src/login1.c b/src/login1.c
index 83d64b6e..af8e8a8e 100644
--- a/src/login1.c
+++ b/src/login1.c
@@ -43,6 +43,7 @@ struct Login1ServicePrivate
 
 enum {
     CAN_GRAPHICAL_CHANGED,
+    ACTIVE_SESSION_CHANGED,
     LAST_SEAT_SIGNAL
 };
 static guint seat_signals[LAST_SEAT_SIGNAL] = { 0 };
@@ -89,6 +90,12 @@ update_property (Login1Seat *seat, const gchar *name, GVariant *value)
         seat->priv->can_graphical = g_variant_get_boolean (value);
         g_signal_emit (seat, seat_signals[CAN_GRAPHICAL_CHANGED], 0);
     }
+    else if (strcmp (name, "ActiveSession") == 0 && g_variant_is_of_type (value, G_VARIANT_TYPE ("(so)")))
+    {
+        const gchar *login1_session_id;
+        g_variant_get (value, "(&so)", &login1_session_id, NULL);
+        g_signal_emit (seat, seat_signals[ACTIVE_SESSION_CHANGED], 0, login1_session_id);
+    }
 }
 
 static void
@@ -133,6 +140,7 @@ seat_properties_changed_cb (GDBusConnection *connection,
         {
             g_variant_get (result, "(v)", &value);
             update_property (seat, name, value);
+            g_variant_unref (value);
             g_variant_unref (result);
         }
     }
@@ -531,4 +539,13 @@ login1_seat_class_init (Login1SeatClass *klass)
                       NULL, NULL,
                       NULL,
                       G_TYPE_NONE, 0);
+
+    seat_signals[ACTIVE_SESSION_CHANGED] =
+        g_signal_new (LOGIN1_SIGNAL_ACTIVE_SESION_CHANGED,
+                      G_TYPE_FROM_CLASS (klass),
+                      G_SIGNAL_RUN_LAST,
+                      G_STRUCT_OFFSET (Login1SeatClass, active_session_changed),
+                      NULL, NULL,
+                      NULL,
+                      G_TYPE_NONE, 1, G_TYPE_STRING);
 }
diff --git a/src/login1.h b/src/login1.h
index c266e23d..e34e806b 100644
--- a/src/login1.h
+++ b/src/login1.h
@@ -26,6 +26,7 @@ G_BEGIN_DECLS
 #define LOGIN1_SERVICE_SIGNAL_SEAT_REMOVED "seat-removed"
 
 #define LOGIN1_SEAT_SIGNAL_CAN_GRAPHICAL_CHANGED "can-graphical-changed"
+#define LOGIN1_SIGNAL_ACTIVE_SESION_CHANGED "active-session-changed"
 
 typedef struct Login1SeatPrivate Login1SeatPrivate;
 
@@ -39,6 +40,7 @@ typedef struct
 {
     GObjectClass parent_class;
     void (*can_graphical_changed)(Login1Seat *seat);
+    void (*active_session_changed)(Login1Seat *seat, const gchar *login1_session_id);
 } Login1SeatClass;
 
 typedef struct Login1ServicePrivate Login1ServicePrivate;
diff --git a/src/seat-unity.c b/src/seat-unity.c
index 32d30b23..642be0aa 100644
--- a/src/seat-unity.c
+++ b/src/seat-unity.c
@@ -203,9 +203,11 @@ create_x_server (Seat *seat)
 
     x_server = x_server_local_new ();
 
-    command = seat_get_string_property (seat, "xserver-command");
-    if (command)
-        x_server_local_set_command (x_server, command);
+    command = seat_get_string_property (seat, "xmir-command");
+    /* Fall back to using X if Xmir is not available as this was the previous way XMir worked */
+    if (strcmp (command, "Xmir") == 0 && !g_find_program_in_path ("Xmir"))
+        command = seat_get_string_property (seat, "xserver-command");
+    x_server_local_set_command (x_server, command);
 
     id = g_strdup_printf ("x-%d", SEAT_UNITY (seat)->priv->next_x_server_id);
     SEAT_UNITY (seat)->priv->next_x_server_id++;
diff --git a/src/seat-xremote.c b/src/seat-xremote.c
index 1a46f401..e860e9f3 100644
--- a/src/seat-xremote.c
+++ b/src/seat-xremote.c
@@ -41,7 +41,7 @@ seat_xremote_create_display_server (Seat *seat, Session *session)
 
     hostname = seat_get_string_property (seat, "xserver-hostname");
     if (!hostname)
-        hostname = "localhost";
+        hostname = "127.0.0.1";
     number = seat_get_integer_property (seat, "xserver-display-number");
 
     l_debug (seat, "Starting remote X display %s:%d", hostname, number);
diff --git a/src/seat.c b/src/seat.c
index 9a56baf2..f9b149dd 100644
--- a/src/seat.c
+++ b/src/seat.c
@@ -269,6 +269,54 @@ seat_get_next_session (Seat *seat)
     return seat->priv->next_session;
 }
 
+/**
+ * Obtains the active session which lightdm expects to be active.
+ *
+ * This function is different from seat_get_active_session() in that the
+ * later (in the case of xlocal seats) dynamically finds the session that is
+ * really active (based on the active VT), whereas this function returns the
+ * session that lightdm activated last by itself, which may not be the actual
+ * active session (i.e. VT changes).
+ */
+Session *
+seat_get_expected_active_session (Seat *seat)
+{
+    g_return_val_if_fail (seat != NULL, NULL);
+    return seat->priv->active_session;
+}
+
+/**
+ * Sets the active session which lightdm expects to be active.
+ *
+ * This function is different from seat_set_active_session() in that the
+ * later performs an actual session activation, whereas this function just
+ * updates the active session after the session has been activated by some
+ * means external to lightdm (i.e. VT changes).
+ */
+void
+seat_set_externally_activated_session (Seat *seat, Session *session)
+{
+    g_return_if_fail (seat != NULL);
+    if (seat->priv->active_session)
+        g_object_unref (seat->priv->active_session);
+    seat->priv->active_session = g_object_ref (session);
+}
+
+Session *
+seat_find_session_by_login1_id (Seat *seat, const gchar *login1_session_id)
+{
+    GList *session_link;
+
+    for (session_link = seat->priv->sessions; session_link; session_link = session_link->next)
+    {
+        Session *session = session_link->data;
+        if (g_strcmp0 (login1_session_id, session_get_login1_session_id (session)) == 0)
+            return session;
+    }
+
+    return NULL;
+}
+
 gboolean
 seat_get_can_switch (Seat *seat)
 {
@@ -346,13 +394,15 @@ emit_upstart_signal (const gchar *signal)
 {
     g_return_if_fail (signal != NULL);
     g_return_if_fail (signal[0] != 0);
+    const gchar* argv[] = {"initctl", "-q", "emit", signal, "DISPLAY_MANAGER=lightdm", NULL};
 
     if (getuid () != 0)
         return;
 
-    gchar *cmd = g_strdup_printf ("initctl -q emit %s DISPLAY_MANAGER=lightdm", signal);
-    g_spawn_command_line_async (cmd, NULL); /* OK if it fails, probably not installed */
-    g_free (cmd);
+    /* OK if it fails, probably not installed or not running upstart */
+    g_spawn_async (NULL, argv, NULL,
+            G_SPAWN_SEARCH_PATH | G_SPAWN_STDERR_TO_DEV_NULL,
+            NULL, NULL, NULL, NULL);
 }
 
 static void
diff --git a/src/seat.h b/src/seat.h
index f8781ef5..e8d2bc6f 100644
--- a/src/seat.h
+++ b/src/seat.h
@@ -93,6 +93,12 @@ Session *seat_get_active_session (Seat *seat);
 
 Session *seat_get_next_session (Seat *seat);
 
+void seat_set_externally_activated_session (Seat *seat, Session *session);
+
+Session *seat_get_expected_active_session (Seat *seat);
+
+Session *seat_find_session_by_login1_id (Seat *seat, const gchar *login1_session_id);
+
 gboolean seat_get_can_switch (Seat *seat);
 
 gboolean seat_get_allow_guest (Seat *seat);
diff --git a/src/session-child.c b/src/session-child.c
index c6f8a7ce..e85f57da 100644
--- a/src/session-child.c
+++ b/src/session-child.c
@@ -243,7 +243,7 @@ session_child_run (int argc, char **argv)
     XAuthority *x_authority = NULL;
     gchar *x_authority_filename;
     GDBusConnection *bus;
-    const gchar *login1_session = NULL;
+    const gchar *login1_session_id = NULL;
     gchar *console_kit_cookie = NULL;
     const gchar *locale_value;
     gchar *locale_var;
@@ -545,10 +545,10 @@ session_child_run (int argc, char **argv)
     }
 
     /* Check what logind session we are, or fallback to ConsoleKit */
-    login1_session = pam_getenv (pam_handle, "XDG_SESSION_ID");
-    if (login1_session)
+    login1_session_id = pam_getenv (pam_handle, "XDG_SESSION_ID");
+    if (login1_session_id)
     {
-        write_string (login1_session);
+        write_string (login1_session_id);
         if (version >= 2)
             write_string (NULL);
     }
@@ -768,7 +768,7 @@ session_child_run (int argc, char **argv)
     pam_close_session (pam_handle, 0);
 
     /* Remove credentials */
-    result = pam_setcred (pam_handle, PAM_DELETE_CRED);
+    pam_setcred (pam_handle, PAM_DELETE_CRED);
 
     pam_end (pam_handle, 0);
     pam_handle = NULL;
diff --git a/src/session.c b/src/session.c
index 1ac16109..e25a69a5 100644
--- a/src/session.c
+++ b/src/session.c
@@ -653,6 +653,13 @@ session_get_username (Session *session)
 }
 
 const gchar *
+session_get_login1_session_id (Session *session)
+{
+    g_return_val_if_fail (session != NULL, NULL);
+    return session->priv->login1_session_id;
+}
+
+const gchar *
 session_get_console_kit_cookie (Session *session)
 {
     g_return_val_if_fail (session != NULL, NULL);
@@ -903,6 +910,8 @@ session_init (Session *session)
 {
     session->priv = G_TYPE_INSTANCE_GET_PRIVATE (session, SESSION_TYPE, SessionPrivate);
     session->priv->log_filename = g_strdup (".xsession-errors");
+    session->priv->to_child_input = -1;
+    session->priv->from_child_output = -1;
 }
 
 static void
@@ -917,6 +926,8 @@ session_finalize (GObject *object)
         g_object_unref (self->priv->display_server);
     if (self->priv->pid)
         kill (self->priv->pid, SIGKILL);
+    close (self->priv->to_child_input);
+    close (self->priv->from_child_output);
     if (self->priv->from_child_channel)
         g_io_channel_unref (self->priv->from_child_channel);
     if (self->priv->from_child_watch)
diff --git a/src/session.h b/src/session.h
index 513fd12d..c62303e6 100644
--- a/src/session.h
+++ b/src/session.h
@@ -115,6 +115,8 @@ gboolean session_get_is_started (Session *session);
 
 const gchar *session_get_username (Session *session);
 
+const gchar *session_get_login1_session_id (Session *session);
+
 const gchar *session_get_console_kit_cookie (Session *session);
 
 void session_respond (Session *session, struct pam_response *response);
diff --git a/src/unity-system-compositor.c b/src/unity-system-compositor.c
index 03824284..f4b74eb1 100644
--- a/src/unity-system-compositor.c
+++ b/src/unity-system-compositor.c
@@ -147,7 +147,8 @@ write_message (UnitySystemCompositor *compositor, guint16 id, const guint8 *payl
     data[1] = id & 0xFF;
     data[2] = payload_length >> 8;
     data[3] = payload_length & 0xFF;
-    memcpy (data + 4, payload, payload_length);
+    if (payload)
+        memcpy (data + 4, payload, payload_length);
 
     errno = 0;
     if (write (compositor->priv->to_compositor_pipe[1], data, data_length) != data_length)
diff --git a/src/xdmcp-protocol.c b/src/xdmcp-protocol.c
index eb5517fb..f45e7aeb 100644
--- a/src/xdmcp-protocol.c
+++ b/src/xdmcp-protocol.c
@@ -10,8 +10,10 @@
  */
 
 #include <string.h>
+#include <gio/gio.h>
 
 #include "xdmcp-protocol.h"
+#include "x-authority.h"
 
 typedef struct
 {
@@ -481,13 +483,31 @@ xdmcp_packet_tostring (XDMCPPacket *packet)
         t3 = g_string_new ("");
         for (i = 0; i < packet->Request.n_connections; i++)
         {
-            gchar *t4;
+            XDMCPConnection *connection = &packet->Request.connections[i];
+            GSocketFamily family = G_SOCKET_FAMILY_INVALID;
 
             if (i != 0)
                g_string_append (t3, " ");
-            t4 = data_tostring (&packet->Request.connections[i].address);
-            g_string_append_printf (t3, "(%d, %s)", packet->Request.connections[i].type, t4);
-            g_free (t4);
+
+            if (connection->type == XAUTH_FAMILY_INTERNET && connection->address.length == 4)
+                family = G_SOCKET_FAMILY_IPV4;
+            else if (connection->type == XAUTH_FAMILY_INTERNET6 && connection->address.length == 16)
+                family = G_SOCKET_FAMILY_IPV6;
+
+            if (family != G_SOCKET_FAMILY_INVALID)
+            {
+                GInetAddress *address = g_inet_address_new_from_bytes (connection->address.data, family);
+                gchar *t4 = g_inet_address_to_string (address);
+                g_string_append (t3, t4);
+                g_free (t4);
+                g_object_unref (address);
+            }
+            else
+            {
+                gchar *t4 = data_tostring (&connection->address);
+                g_string_append_printf (t3, "(%d, %s)", connection->type, t4);
+                g_free (t4);
+            }
         }
         string = g_strdup_printf ("Request(display_number=%d connections=[%s] authentication_name='%s' authentication_data=%s authorization_names=[%s] manufacturer_display_id='%s')",
                                   packet->Request.display_number, t3->str, packet->Request.authentication_name, t2,
diff --git a/src/xdmcp-server.c b/src/xdmcp-server.c
index d92b57d9..197dbc11 100644
--- a/src/xdmcp-server.c
+++ b/src/xdmcp-server.c
@@ -277,10 +277,76 @@ decode_key (const gchar *key, guint8 *data)
     }
 }
 
+static GInetAddress *
+connection_to_address (XDMCPConnection *connection)
+{
+    switch (connection->type)
+    {
+    case XAUTH_FAMILY_INTERNET:
+        if (connection->address.length == 4)
+            return g_inet_address_new_from_bytes (connection->address.data, G_SOCKET_FAMILY_IPV4);
+        else
+            return NULL;
+    case XAUTH_FAMILY_INTERNET6:
+        if (connection->address.length == 16)
+            return g_inet_address_new_from_bytes (connection->address.data, G_SOCKET_FAMILY_IPV6);
+        else
+            return NULL;
+    default:
+        return NULL;
+    }
+}
+
+static gssize
+find_address (GInetAddress **addresses, gsize length, GSocketFamily family)
+{
+    int i;
+
+    for (i = 0; i < length; i++)
+    {
+        GInetAddress *address = addresses[i];
+        if (address && g_inet_address_get_family (address) == family)
+            return i;
+    }
+
+    return -1;
+}
+
+static XDMCPConnection *
+choose_connection (XDMCPPacket *packet, GInetAddress *source_address)
+{
+    GInetAddress **addresses;
+    gsize addresses_length, i;
+    gssize index = -1;
+
+    addresses_length = packet->Request.n_connections;
+    addresses = malloc (sizeof (GInetAddress *) * addresses_length);
+    for (i = 0; i < addresses_length; i++)
+        addresses[i] = connection_to_address (&packet->Request.connections[i]);
+
+    /* Use the address the request came in on as this is the least likely to have firewall / routing issues */
+    for (i = 0; i < addresses_length && index < 0; i++)
+        if (g_inet_address_equal (source_address, addresses[i]))
+            index = i;
+
+    /* Otherwise try and find an address that matches the incoming type */
+    if (index < 0)
+        index = find_address (addresses, addresses_length, g_inet_address_get_family (source_address));
+
+    /* Otherwise use the first available */
+    if (index < 0 && addresses_length > 0)
+        index = 0;
+
+    for (i = 0; i < addresses_length; i++)
+        g_object_unref (addresses[i]);
+    g_free (addresses);
+
+    return &packet->Request.connections[index];
+}
+
 static void
 handle_request (XDMCPServer *server, GSocket *socket, GSocketAddress *address, XDMCPPacket *packet)
 {
-    int i;
     XDMCPPacket *response;
     XDMCPSession *session;
     guint8 *authentication_data = NULL;
@@ -292,48 +358,15 @@ handle_request (XDMCPServer *server, GSocket *socket, GSocketAddress *address, X
     guint8 *session_authorization_data = NULL;
     gsize session_authorization_data_length = 0;
     gchar **j;
-    guint16 family;
-    GInetAddress *x_server_address = NULL;
+    XDMCPConnection *connection;
     gchar *display_number;
     XdmAuthKeyRec rho;
 
-    /* Try and find an IPv6 address */
-    for (i = 0; i < packet->Request.n_connections; i++)
-    {
-        XDMCPConnection *connection = &packet->Request.connections[i];
-        if (connection->type == XAUTH_FAMILY_INTERNET6 && connection->address.length == 16)
-        {
-            family = connection->type;
-            x_server_address = g_inet_address_new_from_bytes (connection->address.data, G_SOCKET_FAMILY_IPV6);
-
-            /* We can't use link-local addresses, as we need to know what interface it is on */
-            if (g_inet_address_get_is_link_local (x_server_address))
-            {
-                g_object_unref (x_server_address);
-                x_server_address = NULL;
-            }
-            else
-                break;
-        }
-    }
-
-    /* If no IPv6 address, then try and find an IPv4 one */
-    if (!x_server_address)
-    {
-        for (i = 0; i < packet->Request.n_connections; i++)
-        {
-            XDMCPConnection *connection = &packet->Request.connections[i];
-            if (connection->type == XAUTH_FAMILY_INTERNET && connection->address.length == 4)
-            {
-                family = connection->type;
-                x_server_address = g_inet_address_new_from_bytes (connection->address.data, G_SOCKET_FAMILY_IPV4);
-                break;
-            }
-        }
-    }
+    /* Choose an address to connect back on */
+    connection = choose_connection (packet, g_inet_socket_address_get_address (G_INET_SOCKET_ADDRESS (address)));
 
     /* Decline if haven't got an address we can connect on */
-    if (!x_server_address)
+    if (!connection)
     {
         response = xdmcp_packet_alloc (XDMCP_Decline);
         response->Decline.status = g_strdup ("No valid address found");
@@ -449,34 +482,34 @@ handle_request (XDMCPServer *server, GSocket *socket, GSocketAddress *address, X
     }
 
     session = add_session (server);
-    session->priv->address = x_server_address;
+    session->priv->address = connection_to_address (connection);
     session->priv->display_number = packet->Request.display_number;
     display_number = g_strdup_printf ("%d", packet->Request.display_number);
 
     /* We need to check if this is the loopback address and set the authority
      * for a local connection if this is so as XCB treats "127.0.0.1" as local
      * always */
-    if (g_inet_address_get_is_loopback (x_server_address))
+    if (g_inet_address_get_is_loopback (session->priv->address))
     {
         gchar hostname[1024];
         gethostname (hostname, 1024);
 
         session->priv->authority = x_authority_new (XAUTH_FAMILY_LOCAL,
-                                              (guint8 *) hostname,
-                                              strlen (hostname),
-                                              display_number,
-                                              authorization_name,
-                                              session_authorization_data,
-                                              session_authorization_data_length);
+                                                    (guint8 *) hostname,
+                                                    strlen (hostname),
+                                                    display_number,
+                                                    authorization_name,
+                                                    session_authorization_data,
+                                                    session_authorization_data_length);
     }
     else
-        session->priv->authority = x_authority_new (family,
-                                              g_inet_address_to_bytes (G_INET_ADDRESS (x_server_address)),
-                                              g_inet_address_get_native_size (G_INET_ADDRESS (x_server_address)),
-                                              display_number,
-                                              authorization_name,
-                                              session_authorization_data,
-                                              session_authorization_data_length);
+        session->priv->authority = x_authority_new (connection->type,
+                                                    connection->address.data,
+                                                    connection->address.length,
+                                                    display_number,
+                                                    authorization_name,
+                                                    session_authorization_data,
+                                                    session_authorization_data_length);
     g_free (display_number);
 
     response = xdmcp_packet_alloc (XDMCP_Accept);