This change adds support for the attach event in scripts.

[1] Added a new OnAttach event to Scene/EventManager
  [2] Hooked up existing attach event handler in XEngine.
  [3] Modified SceneGraph and Scene.Inventory to trigger
      attach events at the appropriate places. I was forced
      to distribut the changes across two files because of
      the way attach processing is distributed across the
      two files.
  [4] In the case of RezSingleAttachmentFromInventory it is
      necessary to handle event scheduling in a special way.
      There is no synchronous path available, so the fact
      that this object is attached, and who it is attached to,
      is cached when the ScriptInstance is created. When
      the script is started, the attached handler is driven
      after on_rez (but before changed, this should be reviewed).

Signed-off-by: dr scofield (aka dirk husemann) <drscofield@xyzzyxyzzy.net>

OpenSim/Region/Framework/Scenes/EventManager.cs

@@ -298,6 +298,13 @@ namespace OpenSim.Region.Framework.Scenes
         public delegate void EmptyScriptCompileQueue(int numScriptsFailed, string message);
         public event EmptyScriptCompileQueue OnEmptyScriptCompileQueue;
 
+        /// <summary>
+        /// Called whenever an object is attached, or detached
+        /// from an in-world presence.
+        /// </summary>
+        public delegate void Attach(uint localID, UUID itemID, UUID avatarID);
+        public event Attach OnAttach;
+
         public class MoneyTransferArgs : EventArgs
         {
             public UUID sender;
@@ -438,6 +445,15 @@ namespace OpenSim.Region.Framework.Scenes
         
         private EmptyScriptCompileQueue handlerEmptyScriptCompileQueue = null;
 
+        private Attach handlerOnAttach = null;
+
+        public void TriggerOnAttach(uint localID, UUID itemID, UUID avatarID)
+        {
+            handlerOnAttach = OnAttach;
+            if (handlerOnAttach != null)
+                handlerOnAttach(localID, itemID, avatarID);
+        }
+
         public void TriggerGetScriptRunning(IClientAPI controllingClient, UUID objectID, UUID itemID)
         {
             handlerGetScriptRunning = OnGetScriptRunning;

OpenSim/Region/Framework/Scenes/Scene.Inventory.cs

@@ -2574,6 +2574,11 @@ namespace OpenSim.Region.Framework.Scenes
                 EventManager.TriggerStopScript(part.LocalId, itemID);
         }
 
+        internal void SendAttachEvent(uint localID, UUID itemID, UUID avatarID)
+        {
+            EventManager.TriggerOnAttach(localID, itemID, avatarID);
+        }
+
         public UUID RezSingleAttachment(IClientAPI remoteClient, UUID itemID,
                 uint AttachmentPt)
         {
@@ -2684,6 +2689,7 @@ namespace OpenSim.Region.Framework.Scenes
                     remoteClient.SendRemoveInventoryItem(inventoryID);
                 }
             }
+            SendAttachEvent(part.ParentGroup.LocalId, itemID, UUID.Zero);
         }
 
         public void DetachSingleAttachmentToInv(UUID itemID, IClientAPI remoteClient)

OpenSim/Region/Framework/Scenes/SceneGraph.cs

@@ -489,6 +489,7 @@ namespace OpenSim.Region.Framework.Scenes
             // Calls attach with a Zero position
             //
             AttachObject(remoteClient, objectLocalID, AttachmentPt, rot, Vector3.Zero, false);
+            m_parentScene.SendAttachEvent(objectLocalID, part.ParentGroup.GetFromAssetID(), remoteClient.AgentId);
         }
 
         public SceneObjectGroup RezSingleAttachment(
@@ -537,6 +538,7 @@ namespace OpenSim.Region.Framework.Scenes
                     group = (SceneObjectGroup)entity;
                     if (group.GetFromAssetID() == itemID)
                     {
+                        m_parentScene.SendAttachEvent(group.LocalId, itemID, UUID.Zero);
                         group.DetachToInventoryPrep();
                         m_log.Debug("[DETACH]: Saving attachpoint: " +
                                 ((uint)group.GetAttachmentPoint()).ToString());

OpenSim/Region/ScriptEngine/Shared/Instance/ScriptInstance.cs

@@ -89,6 +89,8 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
         private long m_eventDelayTicks = 0;
         private long m_nextEventTimeTicks = 0;
         private bool m_startOnInit = true;
+        private bool m_isAttachment = false;
+        private UUID m_attachedAvatar = UUID.Zero;
         private StateSource m_stateSource;
         private bool m_postOnRez;
         private bool m_startedFromSavedState = false;
@@ -232,6 +234,8 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
             m_MaxScriptQueue = maxScriptQueue;
             m_stateSource = stateSource;
             m_postOnRez = postOnRez;
+            m_isAttachment = part.IsAttachment;
+            m_attachedAvatar = part.AttachedAvatar;
             m_RegionID = part.ParentGroup.Scene.RegionInfo.RegionID;
 
             if (part != null)
@@ -379,6 +383,12 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
                         new Object[] {new LSL_Types.LSLInteger(m_StartParam)}, new DetectParams[0]));
                 }
 
+                if (m_isAttachment)
+                {
+                    PostEvent(new EventParams("attach",
+                        new object[] { new LSL_Types.LSLString(m_attachedAvatar.ToString()) }, new DetectParams[0]));
+                }
+
                 if (m_stateSource == StateSource.NewRez)
                 {
 //                    m_log.Debug("[Script] Posted changed(CHANGED_REGION_RESTART) to script");
@@ -403,6 +413,12 @@ namespace OpenSim.Region.ScriptEngine.Shared.Instance
                         new Object[] {new LSL_Types.LSLInteger(m_StartParam)}, new DetectParams[0]));
                 }
 
+                if (m_isAttachment)
+                {
+                    PostEvent(new EventParams("attach",
+                        new object[] { new LSL_Types.LSLString(m_attachedAvatar.ToString()) }, new DetectParams[0]));
+                }
+
             }
         }
 

OpenSim/Region/ScriptEngine/XEngine/EventManager.cs

@@ -53,6 +53,7 @@ namespace OpenSim.Region.ScriptEngine.XEngine
             myScriptEngine = _ScriptEngine;
 
             m_log.Info("[XEngine] Hooking up to server events");
+            myScriptEngine.World.EventManager.OnAttach += attach;
             myScriptEngine.World.EventManager.OnObjectGrab += touch_start;
             myScriptEngine.World.EventManager.OnObjectDeGrab += touch_end;
             myScriptEngine.World.EventManager.OnScriptChangedEvent += changed;