[rygel] media-export: Use ref for argument modification

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 31b2d09371895e421815ead6a6ba0681d1698256
Author: Jens Georg <mail jensge org>
Date:   Sun Mar 28 13:57:15 2010 +0200

    media-export: Use ref for argument modification

 .../rygel-media-export-query-container.vala        |    6 ++--
 .../rygel-media-export-root-container.vala         |   26 ++++++++++---------
 2 files changed, 17 insertions(+), 15 deletions(-)
---
diff --git a/src/plugins/media-export/rygel-media-export-query-container.vala b/src/plugins/media-export/rygel-media-export-query-container.vala
index 3130c87..2a7ceae 100644
--- a/src/plugins/media-export/rygel-media-export-query-container.vala
+++ b/src/plugins/media-export/rygel-media-export-query-container.vala
@@ -207,7 +207,7 @@ internal class Rygel.MediaExportQueryContainer : Rygel.MediaDBContainer {
             // pattern contains URL escaped text. This means it might
             // contain '%' chars which will makes sprintf crash
             new_id = this.pattern.replace ("%s", new_id);
-            new_id = register_id (new_id);
+            register_id (ref new_id);
             var container = new MediaExportQueryContainer (this.media_db,
                                                            new_id,
                                                            meta_data);
@@ -219,7 +219,7 @@ internal class Rygel.MediaExportQueryContainer : Rygel.MediaDBContainer {
         return children;
     }
 
-    public static string register_id (string id) {
+    public static void register_id (ref string id) {
         var md5 = Checksum.compute_for_string (ChecksumType.MD5, id);
         if (virtual_container_map == null) {
             virtual_container_map = new HashMap<string,string> ();
@@ -229,7 +229,7 @@ internal class Rygel.MediaExportQueryContainer : Rygel.MediaDBContainer {
             debug ("registering %s for %s", md5, id);
         }
 
-        return PREFIX + md5;
+        id = PREFIX + md5;
     }
 
     public static string? get_virtual_container_definition (string hash) {
diff --git a/src/plugins/media-export/rygel-media-export-root-container.vala b/src/plugins/media-export/rygel-media-export-root-container.vala
index f1a264a..e808b3a 100644
--- a/src/plugins/media-export/rygel-media-export-root-container.vala
+++ b/src/plugins/media-export/rygel-media-export-root-container.vala
@@ -106,18 +106,20 @@ public class Rygel.MediaExportRootContainer : Rygel.MediaDBContainer {
             exp.op == SearchCriteriaOp.EQ) {
             switch (exp.operand2) {
                 case "object.container.album.musicAlbum":
-                    return new MediaExportQueryContainer (
-                                       this.media_db,
-                                       MediaExportQueryContainer.register_id
-                                       ("virtual-container:upnp:album,?"),
-                                       "Albums");
+                    string id = "virtual-container:upnp:album,?";
+                    MediaExportQueryContainer.register_id (ref id);
+
+                    return new MediaExportQueryContainer (this.media_db,
+                                                          id,
+                                                          "Albums");
 
                 case "object.container.person.musicArtist":
-                    return new MediaExportQueryContainer (
-                                       this.media_db,
-                                       MediaExportQueryContainer.register_id
-                                       ("virtual-container:dc:creator,?,upnp:album,?"),
-                                       "Artists");
+                    string id = "virtual-container:dc:creator,?,upnp:album,?";
+                    MediaExportQueryContainer.register_id (ref id);
+
+                    return new MediaExportQueryContainer (this.media_db,
+                                                          id,
+                                                          "Artists");
                 default:
                     return null;
             }
@@ -199,7 +201,7 @@ public class Rygel.MediaExportRootContainer : Rygel.MediaDBContainer {
                               Uri.escape_string (exp_.operand2, "", true) +
                               last_argument;
                     debug ("Translated search request to %s", new_id);
-                    new_id = MediaExportQueryContainer.register_id (new_id);
+                    MediaExportQueryContainer.register_id (ref new_id);
                     query_container = new MediaExportQueryContainer (
                                         this.media_db,
                                         new_id,
@@ -303,7 +305,7 @@ public class Rygel.MediaExportRootContainer : Rygel.MediaDBContainer {
 
                     continue;
                 }
-                id = MediaExportQueryContainer.register_id (id);
+                MediaExportQueryContainer.register_id (ref id);
 
                 var virtual_container = new MediaExportQueryContainer (
                                         this.media_db,