[dconf] dconf reader: don't crash without config database

[Ryan Lortie <ryanl src gnome org>]

commit 34c250cd7fa388624759a6f9de649bc4e2335e61
Author: Ryan Lortie <desrt desrt ca>
Date:   Wed Jun 2 19:27:34 2010 +0200

    dconf reader: don't crash without config database
    
    Avoid null-pointer dereference when there's no ~/.config/dconf file.

 engine/dconf-engine.c |   20 ++++++++++++++------
 1 files changed, 14 insertions(+), 6 deletions(-)
---
diff --git a/engine/dconf-engine.c b/engine/dconf-engine.c
index e708890..14054c9 100644
--- a/engine/dconf-engine.c
+++ b/engine/dconf-engine.c
@@ -49,9 +49,13 @@ dconf_engine_read (DConfEngine   *engine,
   table = gvdb_table_new (filename, FALSE, NULL);
   g_free (filename);
 
-  value = gvdb_table_get_value (table, key, NULL);
-
-  gvdb_table_unref (table);
+  if (table)
+    {
+      value = gvdb_table_get_value (table, key, NULL);
+      gvdb_table_unref (table);
+    }
+  else
+    value = NULL;
 
   return value;
 }
@@ -200,9 +204,13 @@ dconf_engine_list (DConfEngine    *engine,
   table = gvdb_table_new (filename, FALSE, NULL);
   g_free (filename);
 
-  list = gvdb_table_list (table, dir);
-
-  gvdb_table_unref (table);
+  if (table)
+    {
+      list = gvdb_table_list (table, dir);
+      gvdb_table_unref (table);
+    }
+  else
+    list = NULL;
 
   if (list == NULL)
     list = g_new0 (char *, 1);