Add an event for an orderly region shutdown that fires once per region before

the SceneGraph is torn down.

OpenSim/Region/Framework/Scenes/EventManager.cs

@@ -111,6 +111,10 @@ namespace OpenSim.Region.Framework.Scenes
 
         public event ParcelPropertiesUpdateRequest OnParcelPropertiesUpdateRequest;
 
+        public delegate void SceneShuttingDownDelegate(Scene scene);
+
+        public event SceneShuttingDownDelegate OnSceneShuttingDown;
+
         /// <summary>
         /// Fired when an object is touched/grabbed.
         /// </summary>
@@ -2193,5 +2197,26 @@ namespace OpenSim.Region.Framework.Scenes
                 }
             }
         }
+
+        public void TriggerSceneShuttingDown(Scene s)
+        {
+            SceneShuttingDownDelegate handler = OnSceneShuttingDown;
+            if (handler != null)
+            {
+                foreach (SceneShuttingDownDelegate d in handler.GetInvocationList())
+                {
+                    try
+                    {
+                        d(s);
+                    }
+                    catch (Exception e)
+                    {
+                        m_log.ErrorFormat(
+                            "[EVENT MANAGER]: Delegate for TriggerSceneShuttingDown failed - continuing.  {0} {1}", 
+                            e.Message, e.StackTrace);
+                    }
+                }
+            }
+        }
     }
 }

OpenSim/Region/Framework/Scenes/Scene.cs

@@ -1064,6 +1064,8 @@ namespace OpenSim.Region.Framework.Scenes
             shuttingdown = true;
 
             m_log.Debug("[SCENE]: Persisting changed objects");
+            EventManager.TriggerSceneShuttingDown(this);
+
             EntityBase[] entities = GetEntities();
             foreach (EntityBase entity in entities)
             {