Implement co-operative script termination if termination comes during a script wait event (llSleep(), etc.)

This makes use of EventWaitHandles since various web references indicate that Thread.Interrupt() can also cause runtime instability.
If co-op termination is enabled, then termination sets the wait handle instead of waiting for a timeout before possibly aborting the thread.
This allows the script to cleanly terminate if it's in a llSleep/LL function delay or the next time it enters such a wait without any timeout period.
Co-op termination is not yet testable since checking for termination request within loops that never trigger a wait is not yet implemented.
This commit, unlike 1b5c41c, passes the wait handle as an extra parameter through IScript.Initialize() instead of passing IScriptInstance itself.

18 files changed, 327 insertions, 54 deletions

diff --git a/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs b/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
index 5c8b097..92bf85a 100644
--- a/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
+++ b/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
@@ -1738,6 +1738,21 @@ namespace OpenSim.Region.Framework.Scenes
         /// <returns>The part where the script was rezzed if successful.  False otherwise.</returns>
         public SceneObjectPart RezNewScript(UUID agentID, InventoryItemBase itemBase)
         {
+            return RezNewScript(
+                agentID,
+                itemBase,
+                "default\n{\n    state_entry()\n    {\n        llSay(0, \"Script running\");\n    }\n}");
+        }
+
+        /// <summary>
+        /// Rez a new script from nothing with given script text.
+        /// </summary>
+        /// <param name="remoteClient"></param>
+        /// <param name="itemBase">Template item.</param>
+        /// <param name="scriptText"></param>
+        /// <returns>The part where the script was rezzed if successful.  False otherwise.</returns>
+        public SceneObjectPart RezNewScript(UUID agentID, InventoryItemBase itemBase, string scriptText)
+        {
             // The part ID is the folder ID!
             SceneObjectPart part = GetSceneObjectPart(itemBase.Folder);
             if (part == null)
@@ -1757,9 +1772,14 @@ namespace OpenSim.Region.Framework.Scenes
                 return null;
             }
 
-            AssetBase asset = CreateAsset(itemBase.Name, itemBase.Description, (sbyte)itemBase.AssetType,
-                Encoding.ASCII.GetBytes("default\n{\n    state_entry()\n    {\n        llSay(0, \"Script running\");\n    }\n}"),
-                agentID);
+            AssetBase asset 
+                = CreateAsset(
+                    itemBase.Name, 
+                    itemBase.Description, 
+                    (sbyte)itemBase.AssetType,
+                    Encoding.ASCII.GetBytes(scriptText), 
+                    agentID);
+
             AssetService.Store(asset);
 
             TaskInventoryItem taskItem = new TaskInventoryItem();
diff --git a/OpenSim/Region/ScriptEngine/Interfaces/IScriptApi.cs b/OpenSim/Region/ScriptEngine/Interfaces/IScriptApi.cs
index e95cbd7..d2323f5 100644
--- a/OpenSim/Region/ScriptEngine/Interfaces/IScriptApi.cs
+++ b/OpenSim/Region/ScriptEngine/Interfaces/IScriptApi.cs
@@ -26,6 +26,7 @@
  */
 
 using System;
+using System.Threading;
 using OpenMetaverse;
 using OpenSim.Framework;
 using OpenSim.Region.Framework.Scenes;
@@ -40,7 +41,11 @@ namespace OpenSim.Region.ScriptEngine.Interfaces
         /// </summary>
         /// <remarks>
         /// Each API has an identifier, which is used to load the proper runtime assembly at load time.
-        /// <param name='scriptInstance'>/param>
-        void Initialize(IScriptInstance scriptInstance);
+        /// <param name='scriptEngine'>/param>
+        /// <param name='host'>/param>
+        /// <param name='item'>/param>
+        /// <param name='coopSleepHandle'>/param>
+        void Initialize(
+            IScriptEngine scriptEngine, SceneObjectPart host, TaskInventoryItem item, EventWaitHandle coopSleepHandle);
     }
 }
\ No newline at end of file
diff --git a/OpenSim/Region/ScriptEngine/Interfaces/IScriptInstance.cs b/OpenSim/Region/ScriptEngine/Interfaces/IScriptInstance.cs
index 9de2d72..f68612c 100644
--- a/OpenSim/Region/ScriptEngine/Interfaces/IScriptInstance.cs
+++ b/OpenSim/Region/ScriptEngine/Interfaces/IScriptInstance.cs
@@ -28,6 +28,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Threading;
 using OpenMetaverse;
 using log4net;
 using OpenSim.Framework;
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
index 44072c6..d47fd6b 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
@@ -83,10 +83,17 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
     public class LSL_Api : MarshalByRefObject, ILSL_Api, IScriptApi
     {
         private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
+
         protected IScriptEngine m_ScriptEngine;
         protected SceneObjectPart m_host;
 
         /// <summary>
+        /// Used for script sleeps when we are using co-operative script termination.
+        /// </summary>
+        /// <remarks>null if co-operative script termination is not active</remarks>  
+        EventWaitHandle m_coopSleepHandle;       
+
+        /// <summary>
         /// The item that hosts this script
         /// </summary>
         protected TaskInventoryItem m_item;
@@ -110,13 +117,15 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         protected int EMAIL_PAUSE_TIME = 20;  // documented delay value for smtp.
         protected ISoundModule m_SoundModule = null;
 
-        public void Initialize(IScriptInstance scriptInstance)
+        public void Initialize(
+            IScriptEngine scriptEngine, SceneObjectPart host, TaskInventoryItem item, EventWaitHandle coopSleepHandle)
         {
-            m_ScriptEngine = scriptInstance.Engine;
-            m_host = scriptInstance.Part;
-            m_item = scriptInstance.ScriptTask;
+            m_ScriptEngine = scriptEngine;
+            m_host = host;
+            m_item = item;
+            m_coopSleepHandle = coopSleepHandle;
 
-            LoadLimits();  // read script limits from config.
+            LoadConfig();
 
             m_TransferModule =
                     m_ScriptEngine.World.RequestModuleInterface<IMessageTransferModule>();
@@ -129,7 +138,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         /// <summary>
         /// Load configuration items that affect script, object and run-time behavior. */
         /// </summary>
-        private void LoadLimits()
+        private void LoadConfig()
         {
             m_ScriptDelayFactor =
                 m_ScriptEngine.Config.GetFloat("ScriptDelayFactor", 1.0f);
@@ -175,7 +184,16 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
             delay = (int)((float)delay * m_ScriptDelayFactor);
             if (delay == 0)
                 return;
-            System.Threading.Thread.Sleep(delay);
+
+            Sleep(delay);
+        }
+
+        protected virtual void Sleep(int delay)
+        {
+            if (m_coopSleepHandle == null)
+                System.Threading.Thread.Sleep(delay);
+            else if (m_coopSleepHandle.WaitOne(delay))
+                throw new ScriptCoopStopException();
         }
 
         public Scene World
@@ -2914,7 +2932,8 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         {
 //            m_log.Info("llSleep snoozing " + sec + "s.");
             m_host.AddScriptLPS(1);
-            Thread.Sleep((int)(sec * 1000));
+
+            Sleep((int)(sec * 1000));
         }
 
         public LSL_Float llGetMass()
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LS_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LS_Api.cs
index 071c60e..a08ccc8 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LS_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LS_Api.cs
@@ -30,6 +30,7 @@ using System.Reflection;
 using System.Collections;
 using System.Collections.Generic;
 using System.Runtime.Remoting.Lifetime;
+using System.Threading;
 using OpenMetaverse;
 using Nini.Config;
 using OpenSim;
@@ -61,10 +62,11 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         internal bool m_LSFunctionsEnabled = false;
         internal IScriptModuleComms m_comms = null;
 
-        public void Initialize(IScriptInstance scriptInstance)
+        public void Initialize(
+            IScriptEngine scriptEngine, SceneObjectPart host, TaskInventoryItem item, EventWaitHandle coopSleepHandle)
         {
-            m_ScriptEngine = scriptInstance.Engine;
-            m_host = scriptInstance.Part;
+            m_ScriptEngine = scriptEngine;
+            m_host = host;
 
             if (m_ScriptEngine.Config.GetBoolean("AllowLightShareFunctions", false))
                 m_LSFunctionsEnabled = true;
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/MOD_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/MOD_Api.cs
index cbc69aa..981499e 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/MOD_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/MOD_Api.cs
@@ -30,6 +30,7 @@ using System.Reflection;
 using System.Collections;
 using System.Collections.Generic;
 using System.Runtime.Remoting.Lifetime;
+using System.Threading;
 using OpenMetaverse;
 using Nini.Config;
 using OpenSim;
@@ -61,11 +62,12 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         internal bool m_MODFunctionsEnabled = false;
         internal IScriptModuleComms m_comms = null;
 
-        public void Initialize(IScriptInstance scriptInstance)
+        public void Initialize(
+            IScriptEngine scriptEngine, SceneObjectPart host, TaskInventoryItem item, EventWaitHandle coopSleepHandle)
         {
-            m_ScriptEngine = scriptInstance.Engine;
-            m_host = scriptInstance.Part;
-            m_item = scriptInstance.ScriptTask;
+            m_ScriptEngine = scriptEngine;
+            m_host = host;
+            m_item = item;
 
             if (m_ScriptEngine.Config.GetBoolean("AllowMODFunctions", false))
                 m_MODFunctionsEnabled = true;
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/OSSL_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/OSSL_Api.cs
index 33ae5f0..25635ff 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/OSSL_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/OSSL_Api.cs
@@ -142,11 +142,12 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
 
         protected IUrlModule m_UrlModule = null;
 
-        public void Initialize(IScriptInstance scriptInstance)
+        public void Initialize(
+            IScriptEngine scriptEngine, SceneObjectPart host, TaskInventoryItem item, EventWaitHandle coopSleepHandle)
         {
-            m_ScriptEngine = scriptInstance.Engine;
-            m_host = scriptInstance.Part;
-            m_item = scriptInstance.ScriptTask;
+            m_ScriptEngine = scriptEngine;
+            m_host = host;
+            m_item = item;
 
             m_UrlModule = m_ScriptEngine.World.RequestModuleInterface<IUrlModule>();
 
diff --git a/OpenSim/Region/ScriptEngine/Shared/Helpers.cs b/OpenSim/Region/ScriptEngine/Shared/Helpers.cs
index 5a58f73..e02d35e 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Helpers.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Helpers.cs
@@ -81,6 +81,24 @@ namespace OpenSim.Region.ScriptEngine.Shared
         }
     }
 
+    /// <summary>
+    /// Used to signal when the script is stopping in co-operation with the script engine 
+    /// (instead of through Thread.Abort()).
+    /// </summary>
+    [Serializable]
+    public class ScriptCoopStopException : Exception
+    {
+        public ScriptCoopStopException()
+        {
+        }
+
+        protected ScriptCoopStopException(
+                SerializationInfo info, 
+                StreamingContext context)
+        {
+        }
+    }
+
     public class DetectParams
     {
         public const int AGENT = 1;
diff --git a/OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs b/OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs
index a2ff51b..75aea2b 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs
@@ -200,6 +200,10 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
 
         public static readonly long MaxMeasurementPeriod = 30 * TimeSpan.TicksPerMinute;
 
+        private bool m_coopTermination;
+ 
+        private EventWaitHandle m_coopSleepHandle;
+
         public void ClearQueue()
         {
             m_TimerQueued = false;
@@ -233,6 +237,12 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
             m_postOnRez = postOnRez;
             m_AttachedAvatar = Part.ParentGroup.AttachedAvatar;
             m_RegionID = Part.ParentGroup.Scene.RegionInfo.RegionID;
+
+            if (Engine.Config.GetString("ScriptStopStrategy", "abort") == "co-op")
+            {
+                m_coopTermination = true;
+                m_coopSleepHandle = new AutoResetEvent(false);
+            }
         }
 
         /// <summary>
@@ -251,7 +261,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
             foreach (string api in am.GetApis())
             {
                 m_Apis[api] = am.CreateApi(api);
-                m_Apis[api].Initialize(this);
+                m_Apis[api].Initialize(Engine, Part, ScriptTask, m_coopSleepHandle);
             }
     
             try
@@ -532,9 +542,34 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
             }
 
             // Wait for the current event to complete.
-            if (!m_InSelfDelete && workItem.Wait(new TimeSpan((long)timeout * 100000)))
+            if (!m_InSelfDelete)
             {
-                return true;
+                if (!m_coopTermination)
+                {
+                    // If we're not co-operative terminating then try and wait for the event to complete before stopping
+                    if (workItem.Wait(new TimeSpan((long)timeout * 100000)))
+                        return true;
+                }
+                else
+                {
+                    m_log.DebugFormat(
+                        "[SCRIPT INSTANCE]: Co-operatively stopping script {0} {1} in {2} {3}",
+                        ScriptName, ItemID, PrimName, ObjectID);
+
+                    // This will terminate the event on next handle check by the script.
+                    m_coopSleepHandle.Set();
+
+                    // For now, we will wait forever since the event should always cleanly terminate once LSL loop
+                    // checking is implemented.  May want to allow a shorter timeout option later.
+                    if (workItem.Wait(TimeSpan.MaxValue))
+                    {
+                        m_log.DebugFormat(
+                            "[SCRIPT INSTANCE]: Co-operatively stopped script {0} {1} in {2} {3}",
+                            ScriptName, ItemID, PrimName, ObjectID);
+
+                        return true;
+                    }
+                }
             }
 
             lock (EventQueue)
@@ -547,6 +582,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
 
             // If the event still hasn't stopped and we the stop isn't the result of script or object removal, then
             // forcibly abort the work item (this aborts the underlying thread).
+            // Co-operative termination should never reach this point.
             if (!m_InSelfDelete)
             {
                 m_log.DebugFormat(
@@ -786,7 +822,11 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
                             m_InEvent = false;
                             m_CurrentEvent = String.Empty;
 
-                            if ((!(e is TargetInvocationException) || (!(e.InnerException is SelfDeleteException) && !(e.InnerException is ScriptDeleteException))) && !(e is ThreadAbortException))
+                            if ((!(e is TargetInvocationException) 
+                                || (!(e.InnerException is SelfDeleteException) 
+                                    && !(e.InnerException is ScriptDeleteException)
+                                    && !(e.InnerException is ScriptCoopStopException))) 
+                                && !(e is ThreadAbortException))
                             {
                                 try
                                 {
@@ -834,6 +874,12 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
                                 m_InSelfDelete = true;
                                 Part.Inventory.RemoveInventoryItem(ItemID);
                             }
+                            else if ((e is TargetInvocationException) && (e.InnerException is ScriptCoopStopException))
+                            {
+                                m_log.DebugFormat(
+                                    "[SCRIPT INSTANCE]: Script {0}.{1} in event {2}, state {3} stopped co-operatively.",
+                                    PrimName, ScriptName, data.EventName, State);
+                            }
                         }
                     }
                 }
diff --git a/OpenSim/Region/ScriptEngine/Shared/Instance/Tests/CoopTerminationTests.cs b/OpenSim/Region/ScriptEngine/Shared/Instance/Tests/CoopTerminationTests.cs
new file mode 100644
index 0000000..8c3e9e0
--- /dev/null
+++ b/OpenSim/Region/ScriptEngine/Shared/Instance/Tests/CoopTerminationTests.cs
@@ -0,0 +1,157 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using Nini.Config;
+using NUnit.Framework;
+using OpenMetaverse;
+using OpenSim.Framework;
+using OpenSim.Region.CoreModules.Scripting.WorldComm;
+using OpenSim.Region.Framework.Scenes;
+using OpenSim.Region.Framework.Interfaces;
+using OpenSim.Region.ScriptEngine.XEngine;
+using OpenSim.Tests.Common;
+using OpenSim.Tests.Common.Mock;
+
+namespace OpenSim.Region.ScriptEngine.Shared.Instance.Tests
+{
+    /// <summary>
+    /// Test that co-operative script thread termination is working correctly.
+    /// </summary>
+    [TestFixture]
+    public class CoopTerminationTests : OpenSimTestCase
+    {
+        private TestScene m_scene;
+        private OpenSim.Region.ScriptEngine.XEngine.XEngine m_xEngine;
+
+        private AutoResetEvent m_chatEvent = new AutoResetEvent(false);
+        private AutoResetEvent m_stoppedEvent = new AutoResetEvent(false);
+
+        private OSChatMessage m_osChatMessageReceived;
+
+        [TestFixtureSetUp]
+        public void Init()
+        {
+            //AppDomain.CurrentDomain.SetData("APPBASE", Environment.CurrentDirectory + "/bin");
+//            Console.WriteLine(AppDomain.CurrentDomain.BaseDirectory);
+            m_xEngine = new OpenSim.Region.ScriptEngine.XEngine.XEngine();
+
+            IniConfigSource configSource = new IniConfigSource();
+            
+            IConfig startupConfig = configSource.AddConfig("Startup");
+            startupConfig.Set("DefaultScriptEngine", "XEngine");
+
+            IConfig xEngineConfig = configSource.AddConfig("XEngine");
+            xEngineConfig.Set("Enabled", "true");
+            xEngineConfig.Set("StartDelay", "0");
+
+            // These tests will not run with AppDomainLoading = true, at least on mono.  For unknown reasons, the call
+            // to AssemblyResolver.OnAssemblyResolve fails.
+            xEngineConfig.Set("AppDomainLoading", "false");
+
+            xEngineConfig.Set("ScriptStopStrategy", "co-op");
+
+            m_scene = new SceneHelpers().SetupScene("My Test", UUID.Random(), 1000, 1000, configSource);
+            SceneHelpers.SetupSceneModules(m_scene, configSource, m_xEngine);
+            m_scene.StartScripts();
+        }
+
+        /// <summary>
+        /// Test co-operative termination on derez of an object containing a script with a long-running event.
+        /// </summary>
+        /// <remarks>
+        /// TODO: Actually compiling the script is incidental to this test.  Really want a way to compile test scripts
+        /// within the build itself.
+        /// </remarks>
+        [Test]
+        public void TestStopOnLongSleep()
+        {
+            TestHelpers.InMethod();
+//            TestHelpers.EnableLogging();
+
+            UUID userId = TestHelpers.ParseTail(0x1);
+//            UUID objectId = TestHelpers.ParseTail(0x100);
+//            UUID itemId = TestHelpers.ParseTail(0x3);
+            string itemName = "TestStopOnObjectDerezLongSleep() Item";
+
+            SceneObjectGroup so = SceneHelpers.CreateSceneObject(1, userId, "TestStopOnObjectDerezLongSleep", 0x100);
+            m_scene.AddNewSceneObject(so, true);
+
+            InventoryItemBase itemTemplate = new InventoryItemBase();
+//            itemTemplate.ID = itemId;
+            itemTemplate.Name = itemName;
+            itemTemplate.Folder = so.UUID;
+            itemTemplate.InvType = (int)InventoryType.LSL;
+
+            m_scene.EventManager.OnChatFromWorld += OnChatFromWorld;
+
+            SceneObjectPart partWhereRezzed = m_scene.RezNewScript(userId, itemTemplate, 
+@"default
+{    
+    state_entry()
+    {
+        llSay(0, ""Thin Lizzy"");
+        llSleep(60);
+    }
+}");
+
+            TaskInventoryItem rezzedItem = partWhereRezzed.Inventory.GetInventoryItem(itemName);
+
+            // Wait for the script to start the event before we try stopping it.
+            m_chatEvent.WaitOne(60000);
+
+            Console.WriteLine("Script started with message [{0}]", m_osChatMessageReceived.Message);
+
+            // FIXME: This is a very poor way of trying to avoid a low-probability race condition where the script
+            // executes llSay() but has not started the sleep before we try to stop it.
+            Thread.Sleep(1000);
+
+            // We need a way of carrying on if StopScript() fail, since it won't return if the script isn't actually
+            // stopped.  This kind of multi-threading is far from ideal in a regression test.
+            new Thread(() => { m_xEngine.StopScript(rezzedItem.ItemID); m_stoppedEvent.Set(); }).Start();
+
+            if (!m_stoppedEvent.WaitOne(30000))
+                Assert.Fail("Script did not co-operatively stop.");
+
+            bool running;
+            TaskInventoryItem scriptItem = partWhereRezzed.Inventory.GetInventoryItem(itemName);
+            Assert.That(
+                SceneObjectPartInventory.TryGetScriptInstanceRunning(m_scene, scriptItem, out running), Is.True);
+            Assert.That(running, Is.False);
+        }
+
+        private void OnChatFromWorld(object sender, OSChatMessage oscm)
+        {
+//            Console.WriteLine("Got chat [{0}]", oscm.Message);
+
+            m_osChatMessageReceived = oscm;
+            m_chatEvent.Set();
+        }
+    }
+}
\ No newline at end of file
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiInventoryTests.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiInventoryTests.cs
index 36c7582..6dd6c17 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiInventoryTests.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiInventoryTests.cs
@@ -94,7 +94,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             TaskInventoryHelpers.AddSceneObject(m_scene, so1.RootPart, inventoryItemName, itemId, userId);
 
             LSL_Api api = new LSL_Api();
-            api.Initialize(new ScriptInstance(m_engine, so1.RootPart, null, 0, false, int.MaxValue));
+            api.Initialize(m_engine, so1.RootPart, null, null);
 
             // Create a second object
             SceneObjectGroup so2 = SceneHelpers.CreateSceneObject(1, userId, "so2", 0x100);
@@ -127,7 +127,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             SceneObjectGroup so1 = SceneHelpers.CreateSceneObject(1, user1Id, "so1", 0x10);
             m_scene.AddSceneObject(so1);
             LSL_Api api = new LSL_Api();
-            api.Initialize(new ScriptInstance(m_engine, so1.RootPart, null, 0, false, int.MaxValue));
+            api.Initialize(m_engine, so1.RootPart, null, null);
 
             // Create an object embedded inside the first
             UUID itemId = TestHelpers.ParseTail(0x20);
@@ -137,7 +137,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             SceneObjectGroup so2 = SceneHelpers.CreateSceneObject(1, user2Id, "so2", 0x100);
             m_scene.AddSceneObject(so2);
             LSL_Api api2 = new LSL_Api();
-            api2.Initialize(new ScriptInstance(m_engine, so2.RootPart, null, 0, false, int.MaxValue));
+            api2.Initialize(m_engine, so2.RootPart, null, null);
 
             // *** Firstly, we test where llAllowInventoryDrop() has not been called. ***
             api.llGiveInventory(so2.UUID.ToString(), inventoryItemName);
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiLinkingTests.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiLinkingTests.cs
index 5121344..5b57bbe 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiLinkingTests.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiLinkingTests.cs
@@ -105,7 +105,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(grp2);
 
             LSL_Api apiGrp1 = new LSL_Api();
-            apiGrp1.Initialize(new ScriptInstance(m_engine, grp1.RootPart, grp1Item, 0, false, int.MaxValue));
+            apiGrp1.Initialize(m_engine, grp1.RootPart, grp1Item, null);
 
             apiGrp1.llCreateLink(grp2.UUID.ToString(), ScriptBaseClass.TRUE);
 
@@ -132,7 +132,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             grp1Item.PermsMask |= ScriptBaseClass.PERMISSION_CHANGE_LINKS;
 
             LSL_Api apiGrp1 = new LSL_Api();
-            apiGrp1.Initialize(new ScriptInstance(m_engine, grp1.RootPart, grp1Item, 0, false, int.MaxValue));
+            apiGrp1.Initialize(m_engine, grp1.RootPart, grp1Item, null);
 
             apiGrp1.llBreakLink(2);
 
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiListTests.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiListTests.cs
index 28e5831..60de5cb 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiListTests.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiListTests.cs
@@ -68,7 +68,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             engine.AddRegion(scene);
 
             m_lslApi = new LSL_Api();
-            m_lslApi.Initialize(new ScriptInstance(engine, part, null, 0, false, int.MaxValue));
+            m_lslApi.Initialize(engine, part, null, null);
         }
  
         [Test]
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiTest.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiTest.cs
index 48c2465..e97ae06 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiTest.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiTest.cs
@@ -67,7 +67,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             engine.AddRegion(scene);
 
             m_lslApi = new LSL_Api();
-            m_lslApi.Initialize(new ScriptInstance(engine, part, null, 0, false, int.MaxValue));
+            m_lslApi.Initialize(engine, part, null, null);
         }
 
         [Test]
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAppearanceTest.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAppearanceTest.cs
index 5164d4e..c88bad5 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAppearanceTest.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAppearanceTest.cs
@@ -94,7 +94,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             string notecardName = "appearanceNc";
 
@@ -135,7 +135,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             string notecardName = "appearanceNc";
 
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAttachmentTests.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAttachmentTests.cs
index e7b3319..b2803a1 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAttachmentTests.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAttachmentTests.cs
@@ -99,10 +99,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             SceneObjectGroup inWorldObj = SceneHelpers.AddSceneObject(m_scene, "inWorldObj", ua1.PrincipalID);
             TaskInventoryItem scriptItem = TaskInventoryHelpers.AddScript(m_scene, inWorldObj.RootPart);
 
-            ScriptInstance si = new ScriptInstance(m_engine, inWorldObj.RootPart, scriptItem, 0, false, int.MaxValue);
-            new LSL_Api().Initialize(si);
+            new LSL_Api().Initialize(m_engine, inWorldObj.RootPart, scriptItem, null);
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(si);
+            osslApi.Initialize(m_engine, inWorldObj.RootPart, scriptItem, null);
 
 //            SceneObjectGroup sog1 = SceneHelpers.CreateSceneObject(1, ua1.PrincipalID);
 
@@ -146,10 +145,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             SceneObjectGroup inWorldObj = SceneHelpers.AddSceneObject(m_scene, "inWorldObj", ua1.PrincipalID);
             TaskInventoryItem scriptItem = TaskInventoryHelpers.AddScript(m_scene, inWorldObj.RootPart);
 
-            ScriptInstance si = new ScriptInstance(m_engine, inWorldObj.RootPart, scriptItem, 0, false, int.MaxValue);
-            new LSL_Api().Initialize(si);
+            new LSL_Api().Initialize(m_engine, inWorldObj.RootPart, scriptItem, null);
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(si);
+            osslApi.Initialize(m_engine, inWorldObj.RootPart, scriptItem, null);
 
             // Create an object embedded inside the first
             TaskInventoryHelpers.AddNotecard(
@@ -195,10 +193,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             SceneObjectGroup inWorldObj = SceneHelpers.AddSceneObject(m_scene, "inWorldObj", ua1.PrincipalID);
             TaskInventoryItem scriptItem = TaskInventoryHelpers.AddScript(m_scene, inWorldObj.RootPart);
 
-            ScriptInstance si = new ScriptInstance(m_engine, inWorldObj.RootPart, scriptItem, 0, false, int.MaxValue);
-            new LSL_Api().Initialize(si);
+            new LSL_Api().Initialize(m_engine, inWorldObj.RootPart, scriptItem, null);
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(si);
+            osslApi.Initialize(m_engine, inWorldObj.RootPart, scriptItem, null);
 
             // Create an object embedded inside the first
             TaskInventoryHelpers.AddSceneObject(
diff --git a/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiNpcTests.cs b/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiNpcTests.cs
index 584f44f..1f8a6e5 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiNpcTests.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiNpcTests.cs
@@ -100,7 +100,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             string notecardName = "appearanceNc";
             osslApi.osOwnerSaveAppearance(notecardName);
@@ -126,7 +126,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, so.RootPart, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, so.RootPart, null, null);
 
             bool gotExpectedException = false;
             try
@@ -161,7 +161,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             string notecardName = "appearanceNc";
             osslApi.osOwnerSaveAppearance(notecardName);
@@ -195,7 +195,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             osslApi.osOwnerSaveAppearance(firstAppearanceNcName);
 
@@ -233,7 +233,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             osslApi.osOwnerSaveAppearance(firstAppearanceNcName);
 
@@ -285,10 +285,10 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(otherSo);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             OSSL_Api otherOsslApi = new OSSL_Api();
-            otherOsslApi.Initialize(new ScriptInstance(m_engine, otherPart, null, 0, false, int.MaxValue));
+            otherOsslApi.Initialize(m_engine, otherPart, null, null);
 
             string notecardName = "appearanceNc";
             osslApi.osOwnerSaveAppearance(notecardName);
@@ -332,7 +332,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_scene.AddSceneObject(so);
 
             OSSL_Api osslApi = new OSSL_Api();
-            osslApi.Initialize(new ScriptInstance(m_engine, part, null, 0, false, int.MaxValue));
+            osslApi.Initialize(m_engine, part, null, null);
 
             string notecardName = "appearanceNc";
             osslApi.osOwnerSaveAppearance(notecardName);
diff --git a/OpenSim/Region/ScriptEngine/XEngine/XEngine.cs b/OpenSim/Region/ScriptEngine/XEngine/XEngine.cs
index 186ae04..a17a018 100644
--- a/OpenSim/Region/ScriptEngine/XEngine/XEngine.cs
+++ b/OpenSim/Region/ScriptEngine/XEngine/XEngine.cs
@@ -1716,9 +1716,14 @@ namespace OpenSim.Region.ScriptEngine.XEngine
             IScriptInstance instance = GetInstance(itemID);
 
             if (instance != null)
+            {
                 instance.Stop(m_WaitForEventCompletionOnScriptStop);
+            }
             else
+            {
+//                m_log.DebugFormat("[XENGINE]: Could not find script with ID {0} to stop in {1}", itemID, World.Name);
                 m_runFlags.AddOrUpdate(itemID, false, 240);
+            }
         }
 
         public DetectParams GetDetectParams(UUID itemID, int idx)