//******************************************************************************************************//  BufferPool.cs - Gbtc////  Copyright © 2010, Grid Protection Alliance.  All Rights Reserved.////  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See//  the NOTICE file distributed with this work for additional information regarding copyright ownership.//  The GPA licenses this file to you under the Eclipse Public License -v 1.0 (the "License"); you may//  not use this file except in compliance with the License. You may obtain a copy of the License at:////      http://www.opensource.org/licenses/eclipse-1.0.php////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////  Code Modification History://  ----------------------------------------------------------------------------------------------------//  10/27/2011 - J. Ritchie Carroll//       Initial version of source generated.//  10/8/2012 - Danyelle Gilliam//        Modified Header////******************************************************************************************************    #region [ Contributor License Agreements ] //******************************************************************************************************////  Copyright © 2011, Grid Protection Alliance.  All Rights Reserved.////  The GPA licenses this file to you under the Eclipse Public License -v 1.0 (the "License"); you may//  not use this file except in compliance with the License. You may obtain a copy of the License at:////      http://www.opensource.org/licenses/eclipse-1.0.php////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////****************************************************************************************************** #endregion using System;using System.Collections.Concurrent;//using System.ServiceModel.Channels; namespace GSF{    /// <summary>    /// Represents a common buffer pool that can be used by an application.    /// </summary>    /// <remarks>    /// <para>    /// The buffer pool is statically created at application startup and is available for all components and classes    /// within an application domain. Every time you need to use a buffer, you take one from the pool, use it, and    /// return it to the pool when done. This process is much faster than creating and destroying a buffer every    /// time you need to use one.    /// </para>    /// <para>    /// It is very imporant to return the buffer to the pool when you are finished using it. If you are using a buffer    /// scoped within a method, make sure to use a try/finally so that you can take the buffer within the try and    /// return the buffer within the finally. If you are using a buffer as a member scoped class field, make sure    /// you use the standard dispose pattern and return the buffer in the <see cref="IDisposable.Dispose"/> method.    /// </para>    /// </remarks>    public static class BufferPool    {        // Note that the buffer manager will create an queue buffers as needed during run-time, the default maximum        // pool size and default maximum buffer sizes are set to int max. Even if an application should max the pool        // size, the buffer manager will still sucessfully provide and manage buffers - they simply won't be cached.        private static ConcurrentDictionary<int, ConcurrentQueue<byte[]>> m_bufferPools = new ConcurrentDictionary<int, ConcurrentQueue<byte[]>>();          private static int GetStandardBufferSize(int bufferSize)        {            int exponent = 10;            long size = (long)Math.Pow(2, exponent);                        while (size <= int.MaxValue)            {                if (bufferSize <= size)                    return (int)size;                                exponent++;                size = (long)Math.Pow(2, exponent);            }                        return int.MaxValue;        }                private static ConcurrentQueue<byte[]> CreateQueue(int bufferSize)        {            return new ConcurrentQueue<byte[]>();                }                /// <summary>        /// Gets a buffer of at least the specified size from the pool.        /// </summary>        /// <param name="bufferSize">The size, in bytes, of the requested buffer.</param>        /// <returns>A byte array that is the requested size of the buffer.</returns>        /// <exception cref="ArgumentOutOfRangeException"><paramref name="bufferSize"/> cannot be less than zero.</exception>        public static byte[] TakeBuffer(int bufferSize)        {            bufferSize = GetStandardBufferSize(bufferSize);                        ConcurrentQueue<byte[]> pool = m_bufferPools.GetOrAdd(bufferSize, CreateQueue);            byte[] buffer;             // Attempt to provide user with a queued buffer            if (!pool.TryDequeue(out buffer))            {                // No buffers are available, create a new buffer for the pool                buffer = new byte[bufferSize];            }             return buffer;        }         /// <summary>        /// Returns a buffer to the pool.        /// </summary>        /// <param name="buffer">A reference to the buffer being returned.</param>        /// <exception cref="ArgumentNullException"><paramref name="buffer"/> reference cannot be null.</exception>        /// <exception cref="ArgumentException">Length of <paramref name="buffer"/> does not match the pool's buffer length property.</exception>        public static void ReturnBuffer(byte[] buffer)        {            int bufferSize = buffer.Length;                        if (bufferSize != GetStandardBufferSize(bufferSize))                throw new InvalidOperationException("Attempt was amde to return an invalid buffer to buffer pool.");                        ConcurrentQueue<byte[]> pool = m_bufferPools[bufferSize];                           if ((object)buffer != null)                pool.Enqueue(buffer);                }         /// <summary>        /// Releases all the buffers currently cached in the pool.        /// </summary>        public static void Clear()        {            m_bufferPools.Clear();        }    }}