[rygel] core: Prevent crash in ImportResource

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 91dad9f3e346f3b7049c341df969707d51e5a519
Author: Jens Georg <mail jensge org>
Date:   Wed Apr 13 14:55:18 2011 +0300

    core: Prevent crash in ImportResource
    
    Throw error when required input arguments are missing.

 src/rygel/rygel-import-resource.vala |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)
---
diff --git a/src/rygel/rygel-import-resource.vala b/src/rygel/rygel-import-resource.vala
index 669b601..6e57e38 100644
--- a/src/rygel/rygel-import-resource.vala
+++ b/src/rygel/rygel-import-resource.vala
@@ -100,10 +100,16 @@ internal class Rygel.ImportResource : GLib.Object, Rygel.StateMachine {
                             typeof (string),
                             out this.destination_uri);
 
-        // Set action return arguments
-        this.action.set ("TransferID", typeof (uint32), this.transfer_id);
-
         try {
+            if (this.source_uri == null || this.destination_uri == null) {
+                throw new ContentDirectoryError.INVALID_ARGS
+                                        ("Must provide source " +
+                                         "and destination URIs");
+            }
+
+            // Set action return arguments
+            this.action.set ("TransferID", typeof (uint32), this.transfer_id);
+
             this.item = yield this.fetch_item ();
         } catch (Error error) {
             warning (_("Failed to get original URI for '%s': %s"),
@@ -159,7 +165,6 @@ internal class Rygel.ImportResource : GLib.Object, Rygel.StateMachine {
                                                this.http_server);
         var media_object = yield this.root_container.find_object (uri.item_id,
                                                                   null);
-
         string msg = null;
 
         if (media_object == null || !(media_object is MediaItem)) {