From 6f2031001bca8f309106c94744b3a7d64b178480 Mon Sep 17 00:00:00 2001
From: "Justin Clark-Casey (justincc)" <jjustincc@googlemail.com>
Date: Thu, 14 Jun 2012 01:36:37 +0100
Subject: [PATCH] Fix a race condition where an object update for a hud could
 be sent to non-owner avatars if the hud was attached directly from within the
 region.

If this happens, then the non-owners would see unremovable huds that they did not own until relog, and sometimes even beyond that.
This was due to a race between the entity update and the attachment code when moving an object from within scene to a hud.
---
 .../ClientStack/Linden/UDP/LLClientView.cs    | 27 ++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs b/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
index c34b6b5c4b..68e8f650c5 100644
--- a/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
+++ b/OpenSim/Region/ClientStack/Linden/UDP/LLClientView.cs
@@ -3725,8 +3725,6 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                         }
                     }
     
-                    ++updatesThisCall;
-    
                     #region UpdateFlags to packet type conversion
     
                     PrimUpdateFlags updateFlags = (PrimUpdateFlags)update.Flags;
@@ -3791,7 +3789,15 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                         }
                         else
                         {
-                            updateBlock = CreatePrimUpdateBlock((SceneObjectPart)update.Entity, AgentId);
+                            SceneObjectPart part = (SceneObjectPart)update.Entity;
+                            updateBlock = CreatePrimUpdateBlock(part, AgentId);
+
+                            // If the part has become a private hud since the update was scheduled then we do not
+                            // want to send it to other avatars.
+                            if (part.ParentGroup.IsAttachment
+                                && part.ParentGroup.HasPrivateAttachmentPoint
+                                && part.ParentGroup.AttachedAvatar != AgentId)
+                                continue;
                         }
 
                         objectUpdateBlocks.Value.Add(updateBlock);
@@ -3814,6 +3820,19 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                         {
                             // Everything else goes here
                             terseUpdateBlocks.Value.Add(CreateImprovedTerseBlock(update.Entity, updateFlags.HasFlag(PrimUpdateFlags.Textures)));
+
+                            if (update.Entity is SceneObjectPart)
+                            {
+                                SceneObjectPart part = (SceneObjectPart)update.Entity;
+
+                                // If the part has become a private hud since the update was scheduled then we do not
+                                // want to send it to other avatars.
+                                if (part.ParentGroup.IsAttachment
+                                    && part.ParentGroup.HasPrivateAttachmentPoint
+                                    && part.ParentGroup.AttachedAvatar != AgentId)
+                                    continue;
+                            }
+
                             terseUpdates.Value.Add(update);
                         }
                     }
@@ -3883,6 +3902,8 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                     // If any of the packets created from this call go unacknowledged, all of the updates will be resent
                     OutPacket(packet, ThrottleOutPacketType.Task, true, delegate(OutgoingPacket oPacket) { ResendPrimUpdates(terseUpdates.Value, oPacket); });
                 }
+
+                ++updatesThisCall;
             }
 
             #endregion Packet Sending