[gdm] slave: fail gracefully when fed an invalid display id

[Ray Strode <halfline src gnome org>]

commit e0e9ca7bb345c009ab87247137f674153339b776
Author: Ray Strode <rstrode redhat com>
Date:   Mon Feb 3 15:46:28 2014 -0500

    slave: fail gracefully when fed an invalid display id

 daemon/gdm-slave.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/daemon/gdm-slave.c b/daemon/gdm-slave.c
index 851f1ef..459eb20 100644
--- a/daemon/gdm-slave.c
+++ b/daemon/gdm-slave.c
@@ -666,7 +666,7 @@ static gboolean
 gdm_slave_real_start (GdmSlave *slave)
 {
         gboolean    res;
-        char       *id;
+        char       *id = NULL;
         GError     *error;
         GVariant   *x11_cookie;
         const char *x11_cookie_bytes;
@@ -696,7 +696,7 @@ gdm_slave_real_start (GdmSlave *slave)
                                                  &id,
                                                  NULL,
                                                  &error);
-        if (! res) {
+        if (! res || !id) {
                 g_warning ("Failed to get display ID %s: %s", slave->priv->display_id, error->message);
                 g_error_free (error);
                 return FALSE;
@@ -705,8 +705,8 @@ gdm_slave_real_start (GdmSlave *slave)
         g_debug ("GdmSlave: Got display ID: %s", id);
 
         if (strcmp (id, slave->priv->display_id) != 0) {
-                g_critical ("Display ID doesn't match");
-                exit (1);
+                g_warning ("Display ID doesn't match");
+                return FALSE;
         }
 
         gdm_slave_set_slave_bus_name (slave);