1 files changed, 65 insertions, 210 deletions

diff --git a/OpenSim/Region/ClientStack/LindenUDP/LLUDPClientCollection.cs b/OpenSim/Region/ClientStack/LindenUDP/LLUDPClientCollection.cs
index dbb9861..2972d46 100644
--- a/OpenSim/Region/ClientStack/LindenUDP/LLUDPClientCollection.cs
+++ b/OpenSim/Region/ClientStack/LindenUDP/LLUDPClientCollection.cs
@@ -30,253 +30,108 @@ using System.Collections.Generic;
 using System.Net;
 using OpenSim.Framework;
 using OpenMetaverse;
+using BclExtras.Collections;
 
 using ReaderWriterLockImpl = OpenMetaverse.ReaderWriterLockSlim;
 
 namespace OpenSim.Region.ClientStack.LindenUDP
 {
+    /// <summary>
+    /// A thread safe mapping from endpoints to client references
+    /// </summary>
     public sealed class UDPClientCollection
     {
-        Dictionary<UUID, LLUDPClient> Dictionary1;
-        Dictionary<IPEndPoint, LLUDPClient> Dictionary2;
-        LLUDPClient[] Array;
-        ReaderWriterLockImpl rwLock = new ReaderWriterLockImpl();
-        object m_sync = new object();
+        #region IComparers
 
-        public UDPClientCollection()
-        {
-            Dictionary1 = new Dictionary<UUID, LLUDPClient>();
-            Dictionary2 = new Dictionary<IPEndPoint, LLUDPClient>();
-            Array = new LLUDPClient[0];
-        }
-
-        public UDPClientCollection(int capacity)
-        {
-            Dictionary1 = new Dictionary<UUID, LLUDPClient>(capacity);
-            Dictionary2 = new Dictionary<IPEndPoint, LLUDPClient>(capacity);
-            Array = new LLUDPClient[0];
-        }
-
-        public void Add(UUID key1, IPEndPoint key2, LLUDPClient value)
+        private sealed class IPEndPointComparer : IComparer<IPEndPoint>
         {
-            //rwLock.EnterWriteLock();
-
-            //try
-            //{
-            //    if (Dictionary1.ContainsKey(key1))
-            //    {
-            //        if (!Dictionary2.ContainsKey(key2))
-            //            throw new ArgumentException("key1 exists in the dictionary but not key2");
-            //    }
-            //    else if (Dictionary2.ContainsKey(key2))
-            //    {
-            //        if (!Dictionary1.ContainsKey(key1))
-            //            throw new ArgumentException("key2 exists in the dictionary but not key1");
-            //    }
-
-            //    Dictionary1[key1] = value;
-            //    Dictionary2[key2] = value;
-
-            //    LLUDPClient[] oldArray = Array;
-            //    int oldLength = oldArray.Length;
-
-            //    LLUDPClient[] newArray = new LLUDPClient[oldLength + 1];
-            //    for (int i = 0; i < oldLength; i++)
-            //        newArray[i] = oldArray[i];
-            //    newArray[oldLength] = value;
-
-            //    Array = newArray;
-            //}
-            //finally { rwLock.ExitWriteLock(); }
-
-            lock (m_sync)
+            public int Compare(IPEndPoint x, IPEndPoint y)
             {
-                if (Dictionary1.ContainsKey(key1))
-                {
-                    if (!Dictionary2.ContainsKey(key2))
-                        throw new ArgumentException("key1 exists in the dictionary but not key2");
-                }
-                else if (Dictionary2.ContainsKey(key2))
-                {
-                    if (!Dictionary1.ContainsKey(key1))
-                        throw new ArgumentException("key2 exists in the dictionary but not key1");
-                }
-
-                Dictionary1[key1] = value;
-                Dictionary2[key2] = value;
-
-                LLUDPClient[] oldArray = Array;
-                int oldLength = oldArray.Length;
-
-                LLUDPClient[] newArray = new LLUDPClient[oldLength + 1];
-                for (int i = 0; i < oldLength; i++)
-                    newArray[i] = oldArray[i];
-                newArray[oldLength] = value;
-
-                Array = newArray;
+                int result = x.Address.Address.CompareTo(y.Address.Address);
+                if (result == 0) result = x.Port.CompareTo(y.Port);
+                return result;
             }
-
         }
 
-        public bool Remove(UUID key1, IPEndPoint key2)
-        {
-            //rwLock.EnterWriteLock();
-
-            //try
-            //{
-            //    LLUDPClient value;
-            //    if (Dictionary1.TryGetValue(key1, out value))
-            //    {
-            //        Dictionary1.Remove(key1);
-            //        Dictionary2.Remove(key2);
-
-            //        LLUDPClient[] oldArray = Array;
-            //        int oldLength = oldArray.Length;
-
-            //        LLUDPClient[] newArray = new LLUDPClient[oldLength - 1];
-            //        int j = 0;
-            //        for (int i = 0; i < oldLength; i++)
-            //        {
-            //            if (oldArray[i] != value)
-            //                newArray[j++] = oldArray[i];
-            //        }
-
-            //        Array = newArray;
-            //        return true;
-            //    }
-            //}
-            //finally { rwLock.ExitWriteLock(); }
-
-            //return false;
-
-            lock (m_sync)
-            {
-                LLUDPClient value;
-                if (Dictionary1.TryGetValue(key1, out value))
-                {
-                    Dictionary1.Remove(key1);
-                    Dictionary2.Remove(key2);
-
-                    LLUDPClient[] oldArray = Array;
-                    int oldLength = oldArray.Length;
-
-                    LLUDPClient[] newArray = new LLUDPClient[oldLength - 1];
-                    int j = 0;
-                    for (int i = 0; i < oldLength; i++)
-                    {
-                        if (oldArray[i] != value)
-                            newArray[j++] = oldArray[i];
-                    }
+        #endregion IComparers
 
-                    Array = newArray;
-                    return true;
-                }
-            }
-
-            return false;
+        /// <summary>An immutable dictionary mapping from <seealso cref="IPEndPoint"/>
+        /// to <seealso cref="LLUDPClient"/> references</summary>
+        private ImmutableMap<IPEndPoint, LLUDPClient> m_dict;
+        /// <summary>Immutability grants thread safety for concurrent reads and
+        /// read-writes, but not concurrent writes</summary>
+        private object m_writeLock = new object();
 
-        }
+        /// <summary>Number of clients in the collection</summary>
+        public int Count { get { return m_dict.Count; } }
 
-        public void Clear()
+        /// <summary>
+        /// Default constructor
+        /// </summary>
+        public UDPClientCollection()
         {
-            //rwLock.EnterWriteLock();
-
-            //try
-            //{
-            //    Dictionary1.Clear();
-            //    Dictionary2.Clear();
-            //    Array = new LLUDPClient[0];
-            //}
-            //finally { rwLock.ExitWriteLock(); }
-
-            lock (m_sync)
-            {
-                Dictionary1.Clear();
-                Dictionary2.Clear();
-                Array = new LLUDPClient[0];
-            }
-
+            m_dict = new ImmutableMap<IPEndPoint, LLUDPClient>(new IPEndPointComparer());
         }
 
-        public int Count
+        /// <summary>
+        /// Add a client reference to the collection
+        /// </summary>
+        /// <param name="key">Remote endpoint of the client</param>
+        /// <param name="value">Reference to the client object</param>
+        public void Add(IPEndPoint key, LLUDPClient value)
         {
-            get { return Array.Length; }
+            lock (m_writeLock)
+                m_dict = m_dict.Add(key, value);
         }
 
-        public bool ContainsKey(UUID key)
+        /// <summary>
+        /// Remove a client from the collection
+        /// </summary>
+        /// <param name="key">Remote endpoint of the client</param>
+        public void Remove(IPEndPoint key)
         {
-            return Dictionary1.ContainsKey(key);
+            lock (m_writeLock)
+                m_dict = m_dict.Delete(key);
         }
 
-        public bool ContainsKey(IPEndPoint key)
+        /// <summary>
+        /// Resets the client collection
+        /// </summary>
+        public void Clear()
         {
-            return Dictionary2.ContainsKey(key);
+            lock (m_writeLock)
+                m_dict = new ImmutableMap<IPEndPoint, LLUDPClient>(new IPEndPointComparer());
         }
 
-        public bool TryGetValue(UUID key, out LLUDPClient value)
+        /// <summary>
+        /// Checks if an endpoint is in the collection
+        /// </summary>
+        /// <param name="key">Endpoint to check for</param>
+        /// <returns>True if the endpoint was found in the collection, otherwise false</returns>
+        public bool ContainsKey(IPEndPoint key)
         {
-            ////bool success;
-            ////bool doLock = !rwLock.IsUpgradeableReadLockHeld;
-            ////if (doLock) rwLock.EnterReadLock();
-
-            ////try { success = Dictionary1.TryGetValue(key, out value); }
-            ////finally { if (doLock) rwLock.ExitReadLock(); }
-
-            ////return success;
-
-            lock (m_sync)
-                return Dictionary1.TryGetValue(key, out value); 
-
-            //try
-            //{
-            //    return Dictionary1.TryGetValue(key, out value);
-            //}
-            //catch { }
-            //value = null;
-            //return false;
+            return m_dict.ContainsKey(key);
         }
 
+        /// <summary>
+        /// Attempts to fetch a value out of the collection
+        /// </summary>
+        /// <param name="key">Endpoint of the client to retrieve</param>
+        /// <param name="value">Retrieved client, or null on lookup failure</param>
+        /// <returns>True if the lookup succeeded, otherwise false</returns>
         public bool TryGetValue(IPEndPoint key, out LLUDPClient value)
         {
-            ////bool success;
-            ////bool doLock = !rwLock.IsUpgradeableReadLockHeld;
-            ////if (doLock) rwLock.EnterReadLock();
-
-            ////try { success = Dictionary2.TryGetValue(key, out value); }
-            ////finally { if (doLock) rwLock.ExitReadLock(); }
-
-            ////return success;
-
-            lock (m_sync)
-                return Dictionary2.TryGetValue(key, out value);
-
-            //try
-            //{
-            //    return Dictionary2.TryGetValue(key, out value);
-            //}
-            //catch { }
-            //value = null;
-            //return false;
-
+            return m_dict.TryGetValue(key, out value);
         }
 
+        /// <summary>
+        /// Performs a given task in parallel for each of the elements in the
+        /// collection
+        /// </summary>
+        /// <param name="action">Action to perform on each element</param>
         public void ForEach(Action<LLUDPClient> action)
         {
-            //bool doLock = !rwLock.IsUpgradeableReadLockHeld;
-            //if (doLock) rwLock.EnterUpgradeableReadLock();
-
-            //try { Parallel.ForEach<LLUDPClient>(Array, action); }
-            //finally { if (doLock) rwLock.ExitUpgradeableReadLock(); }
-
-            LLUDPClient[] localArray = null;
-            lock (m_sync)
-            {
-                localArray = new LLUDPClient[Array.Length];
-                Array.CopyTo(localArray, 0);
-            }
-
-            Parallel.ForEach<LLUDPClient>(localArray, action); 
-
+            Parallel.ForEach<LLUDPClient>(m_dict.Values, action); 
         }
     }
 }