Stop an exception being thrown and a teleport/border cross failing if the desintation sim has no active script engines.

This involves getting IScene.RequestModuleInterfaces() to return an empty array (as was stated in the method doc) rather than an array containing one null entry.
Callers adjusted to stop checking for the list reference being null (which never happened anyway)

5 files changed, 41 insertions, 32 deletions

diff --git a/OpenSim/Framework/IScene.cs b/OpenSim/Framework/IScene.cs
index f1b4732..76b731f 100644
--- a/OpenSim/Framework/IScene.cs
+++ b/OpenSim/Framework/IScene.cs
@@ -102,12 +102,28 @@ namespace OpenSim.Framework
 
         bool TryGetScenePresence(UUID agentID, out object scenePresence);
 
-        T RequestModuleInterface<T>();
-        T[] RequestModuleInterfaces<T>();
-
+        /// <summary>
+        /// Register an interface to a region module.  This allows module methods to be called directly as
+        /// well as via events.  If there is already a module registered for this interface, it is not replaced
+        /// (is this the best behaviour?)
+        /// </summary>
+        /// <param name="mod"></param>
         void RegisterModuleInterface<M>(M mod);
+        
         void StackModuleInterface<M>(M mod);
 
+        /// <summary>
+        /// For the given interface, retrieve the region module which implements it.
+        /// </summary>
+        /// <returns>null if there is no registered module implementing that interface</returns>
+        T RequestModuleInterface<T>();
+
+        /// <summary>
+        /// For the given interface, retrieve an array of region modules that implement it.
+        /// </summary>
+        /// <returns>an empty array if there are no registered modules implementing that interface</returns>
+        T[] RequestModuleInterfaces<T>();
+
 //        void AddCommand(object module, string command, string shorthelp, string longhelp, CommandDelegate callback);
 
         ISceneObject DeserializeObject(string representation);
diff --git a/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs b/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
index 663aa22..26eb729 100644
--- a/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
+++ b/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
@@ -82,16 +82,9 @@ namespace OpenSim.Region.Framework.Scenes
             m_log.Info("[PRIM INVENTORY]: Starting scripts in scene");
 
             IScriptModule[] engines = RequestModuleInterfaces<IScriptModule>();
-            if (engines != null)
-            {
-                foreach (IScriptModule engine in engines)
-                {
-                    if (engine != null)
-                    {
-                        engine.StartProcessing();
-                    }
-                }
-            }
+
+            foreach (IScriptModule engine in engines)
+                engine.StartProcessing();
         }
 
         public void AddUploadedInventoryItem(UUID agentID, InventoryItemBase item)
diff --git a/OpenSim/Region/Framework/Scenes/SceneBase.cs b/OpenSim/Region/Framework/Scenes/SceneBase.cs
index dee2ecb..0336fe5 100644
--- a/OpenSim/Region/Framework/Scenes/SceneBase.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneBase.cs
@@ -449,7 +449,7 @@ namespace OpenSim.Region.Framework.Scenes
             }
             else
             {
-                return new T[] { default(T) };
+                return new T[] {};
             }
         }
         
diff --git a/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs b/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs
index 9446741..d80944b 100644
--- a/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs
@@ -232,8 +232,6 @@ namespace OpenSim.Region.Framework.Scenes
             ArrayList ret = new ArrayList();
 
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
-            if (engines == null) // No engine at all
-                return ret;
 
             foreach (IScriptModule e in engines)
             {
@@ -329,7 +327,7 @@ namespace OpenSim.Region.Framework.Scenes
         private void RestoreSavedScriptState(UUID oldID, UUID newID)
         {
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
-            if (engines == null) // No engine at all
+            if (engines.Length == 0) // No engine at all
                 return;
 
             if (m_part.ParentGroup.m_savedScriptState.ContainsKey(oldID))
@@ -369,6 +367,7 @@ namespace OpenSim.Region.Framework.Scenes
 
                     m_part.ParentGroup.m_savedScriptState[oldID] = newDoc.OuterXml;
                 }
+                
                 foreach (IScriptModule e in engines)
                 {
                     if (e != null)
@@ -377,6 +376,7 @@ namespace OpenSim.Region.Framework.Scenes
                             break;
                     }
                 }
+
                 m_part.ParentGroup.m_savedScriptState.Remove(oldID);
             }
         }
@@ -1129,7 +1129,7 @@ namespace OpenSim.Region.Framework.Scenes
             
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
             
-            if (engines == null) // No engine at all
+            if (engines.Length == 0) // No engine at all
                 return ret;
 
             List<TaskInventoryItem> scripts = GetInventoryScripts();
@@ -1157,7 +1157,7 @@ namespace OpenSim.Region.Framework.Scenes
         public void ResumeScripts()
         {
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
-            if (engines == null)
+            if (engines.Length == 0)
                 return;
 
             List<TaskInventoryItem> scripts = GetInventoryScripts();
diff --git a/OpenSim/Region/Framework/Scenes/ScenePresence.cs b/OpenSim/Region/Framework/Scenes/ScenePresence.cs
index 7d901c9..c2d3501 100644
--- a/OpenSim/Region/Framework/Scenes/ScenePresence.cs
+++ b/OpenSim/Region/Framework/Scenes/ScenePresence.cs
@@ -3525,23 +3525,23 @@ namespace OpenSim.Region.Framework.Scenes
         /// <param name="args">The arguments for the event</param>
         public void SendScriptEventToAttachments(string eventName, Object[] args)
         {
-            if (m_scriptEngines != null)
+            if (m_scriptEngines.Length == 0)
+                return;
+
+            lock (m_attachments)
             {
-                lock (m_attachments)
+                foreach (SceneObjectGroup grp in m_attachments)
                 {
-                    foreach (SceneObjectGroup grp in m_attachments)
+                    // 16384 is CHANGED_ANIMATION
+                    //
+                    // Send this to all attachment root prims
+                    //
+                    foreach (IScriptModule m in m_scriptEngines)
                     {
-                        // 16384 is CHANGED_ANIMATION
-                        //
-                        // Send this to all attachment root prims
-                        //
-                        foreach (IScriptModule m in m_scriptEngines)
-                        {
-                            if (m == null) // No script engine loaded
-                                continue;
+                        if (m == null) // No script engine loaded
+                            continue;
 
-                            m.PostObjectEvent(grp.RootPart.UUID, "changed", new Object[] { (int)Changed.ANIMATION });
-                        }
+                        m.PostObjectEvent(grp.RootPart.UUID, "changed", new Object[] { (int)Changed.ANIMATION });
                     }
                 }
             }