首页 > 代码库 > 【转】C#高性能大容量SOCKET并发(二):SocketAsyncEventArgs封装
【转】C#高性能大容量SOCKET并发(二):SocketAsyncEventArgs封装
http://blog.csdn.net/sqldebug_fan/article/details/17557341
1、SocketAsyncEventArgs介绍
SocketAsyncEventArgs是微软提供的高性能异步Socket实现类,主要为高性能网络服务器应用程序而设计,主要是为了避免在在异步套接字 I/O 量非常大时发生重复的对象分配和同步。使用此类执行异步套接字操作的模式包含以下步骤:
1.分配一个新的 SocketAsyncEventArgs 上下文对象,或者从应用程序池中获取一个空闲的此类对象。
2.将该上下文对象的属性设置为要执行的操作(例如,完成回调方法、数据缓冲区、缓冲区偏移量以及要传输的最大数据量)。
3.调用适当的套接字方法 (xxxAsync) 以启动异步操作。
4.如果异步套接字方法 (xxxAsync) 返回 true,则在回调中查询上下文属性来获取完成状态。
5.如果异步套接字方法 (xxxAsync) 返回 false,则说明操作是同步完成的。 可以查询上下文属性来获取操作结果。
6.将该上下文重用于另一个操作,将它放回到应用程序池中,或者将它丢弃。
2、SocketAsyncEventArgs封装
使用SocketAsyncEventArgs之前需要先建立一个Socket监听对象,使用如下代码:
然后开始接受连接,SocketAsyncEventArgs有连接时会通过Completed事件通知外面,所以接受连接的代码如下:[csharp] view plain copy
- public void Start(IPEndPoint localEndPoint)
- {
- listenSocket = new Socket(localEndPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
- listenSocket.Bind(localEndPoint);
- listenSocket.Listen(m_numConnections);
- Program.Logger.InfoFormat("Start listen socket {0} success", localEndPoint.ToString());
- //for (int i = 0; i < 64; i++) //不能循环投递多次AcceptAsync,会造成只接收8000连接后不接收连接了
- StartAccept(null);
- m_daemonThread = new DaemonThread(this);
- }
接受连接响应事件代码:[csharp] view plain copy
- public void StartAccept(SocketAsyncEventArgs acceptEventArgs)
- {
- if (acceptEventArgs == null)
- {
- acceptEventArgs = new SocketAsyncEventArgs();
- acceptEventArgs.Completed += new EventHandler<SocketAsyncEventArgs>(AcceptEventArg_Completed);
- }
- else
- {
- acceptEventArgs.AcceptSocket = null; //释放上次绑定的Socket,等待下一个Socket连接
- }
- m_maxNumberAcceptedClients.WaitOne(); //获取信号量
- bool willRaiseEvent = listenSocket.AcceptAsync(acceptEventArgs);
- if (!willRaiseEvent)
- {
- ProcessAccept(acceptEventArgs);
- }
- }
[csharp] view plain copy
- void AcceptEventArg_Completed(object sender, SocketAsyncEventArgs acceptEventArgs)
- {
- try
- {
- ProcessAccept(acceptEventArgs);
- }
- catch (Exception E)
- {
- Program.Logger.ErrorFormat("Accept client {0} error, message: {1}", acceptEventArgs.AcceptSocket, E.Message);
- Program.Logger.Error(E.StackTrace);
- }
- }
接受连接后,从当前Socket缓冲池AsyncSocketUserTokenPool中获取一个用户对象AsyncSocketUserToken,AsyncSocketUserToken包含一个接收异步事件m_receiveEventArgs,一个发送异步事件m_sendEventArgs,接收数据缓冲区m_receiveBuffer,发送数据缓冲区m_sendBuffer,协议逻辑调用对象m_asyncSocketInvokeElement,建立服务对象后,需要实现接收和发送的事件响应函数:[csharp] view plain copy
- private void ProcessAccept(SocketAsyncEventArgs acceptEventArgs)
- {
- Program.Logger.InfoFormat("Client connection accepted. Local Address: {0}, Remote Address: {1}",
- acceptEventArgs.AcceptSocket.LocalEndPoint, acceptEventArgs.AcceptSocket.RemoteEndPoint);
- AsyncSocketUserToken userToken = m_asyncSocketUserTokenPool.Pop();
- m_asyncSocketUserTokenList.Add(userToken); //添加到正在连接列表
- userToken.ConnectSocket = acceptEventArgs.AcceptSocket;
- userToken.ConnectDateTime = DateTime.Now;
- try
- {
- bool willRaiseEvent = userToken.ConnectSocket.ReceiveAsync(userToken.ReceiveEventArgs); //投递接收请求
- if (!willRaiseEvent)
- {
- lock (userToken)
- {
- ProcessReceive(userToken.ReceiveEventArgs);
- }
- }
- }
- catch (Exception E)
- {
- Program.Logger.ErrorFormat("Accept client {0} error, message: {1}", userToken.ConnectSocket, E.Message);
- Program.Logger.Error(E.StackTrace);
- }
- StartAccept(acceptEventArgs); //把当前异步事件释放,等待下次连接
- }
在Completed事件中需要处理发送和接收的具体逻辑代码,其中接收的逻辑实现如下:[csharp] view plain copy
- void IO_Completed(object sender, SocketAsyncEventArgs asyncEventArgs)
- {
- AsyncSocketUserToken userToken = asyncEventArgs.UserToken as AsyncSocketUserToken;
- userToken.ActiveDateTime = DateTime.Now;
- try
- {
- lock (userToken)
- {
- if (asyncEventArgs.LastOperation == SocketAsyncOperation.Receive)
- ProcessReceive(asyncEventArgs);
- else if (asyncEventArgs.LastOperation == SocketAsyncOperation.Send)
- ProcessSend(asyncEventArgs);
- else
- throw new ArgumentException("The last operation completed on the socket was not a receive or send");
- }
- }
- catch (Exception E)
- {
- Program.Logger.ErrorFormat("IO_Completed {0} error, message: {1}", userToken.ConnectSocket, E.Message);
- Program.Logger.Error(E.StackTrace);
- }
- }
由于我们制定的协议第一个字节是协议标识,因此在接收到第一个字节的时候需要绑定协议解析对象,具体代码实现如下:[csharp] view plain copy
- private void ProcessReceive(SocketAsyncEventArgs receiveEventArgs)
- {
- AsyncSocketUserToken userToken = receiveEventArgs.UserToken as AsyncSocketUserToken;
- if (userToken.ConnectSocket == null)
- return;
- userToken.ActiveDateTime = DateTime.Now;
- if (userToken.ReceiveEventArgs.BytesTransferred > 0 && userToken.ReceiveEventArgs.SocketError == SocketError.Success)
- {
- int offset = userToken.ReceiveEventArgs.Offset;
- int count = userToken.ReceiveEventArgs.BytesTransferred;
- if ((userToken.AsyncSocketInvokeElement == null) & (userToken.ConnectSocket != null)) //存在Socket对象,并且没有绑定协议对象,则进行协议对象绑定
- {
- BuildingSocketInvokeElement(userToken);
- offset = offset + 1;
- count = count - 1;
- }
- if (userToken.AsyncSocketInvokeElement == null) //如果没有解析对象,提示非法连接并关闭连接
- {
- Program.Logger.WarnFormat("Illegal client connection. Local Address: {0}, Remote Address: {1}", userToken.ConnectSocket.LocalEndPoint,
- userToken.ConnectSocket.RemoteEndPoint);
- CloseClientSocket(userToken);
- }
- else
- {
- if (count > 0) //处理接收数据
- {
- if (!userToken.AsyncSocketInvokeElement.ProcessReceive(userToken.ReceiveEventArgs.Buffer, offset, count))
- { //如果处理数据返回失败,则断开连接
- CloseClientSocket(userToken);
- }
- else //否则投递下次介绍数据请求
- {
- bool willRaiseEvent = userToken.ConnectSocket.ReceiveAsync(userToken.ReceiveEventArgs); //投递接收请求
- if (!willRaiseEvent)
- ProcessReceive(userToken.ReceiveEventArgs);
- }
- }
- else
- {
- bool willRaiseEvent = userToken.ConnectSocket.ReceiveAsync(userToken.ReceiveEventArgs); //投递接收请求
- if (!willRaiseEvent)
- ProcessReceive(userToken.ReceiveEventArgs);
- }
- }
- }
- else
- {
- CloseClientSocket(userToken);
- }
- }
发送响应函数实现需要注意,我们是把发送数据放到一个列表中,当上一个发送事件完成响应Completed事件,这时我们需要检测发送队列中是否存在未发送的数据,如果存在则继续发送。[csharp] view plain copy
- private void BuildingSocketInvokeElement(AsyncSocketUserToken userToken)
- {
- byte flag = userToken.ReceiveEventArgs.Buffer[userToken.ReceiveEventArgs.Offset];
- if (flag == (byte)SocketFlag.Upload)
- userToken.AsyncSocketInvokeElement = new UploadSocketProtocol(this, userToken);
- else if (flag == (byte)SocketFlag.Download)
- userToken.AsyncSocketInvokeElement = new DownloadSocketProtocol(this, userToken);
- else if (flag == (byte)SocketFlag.RemoteStream)
- userToken.AsyncSocketInvokeElement = new RemoteStreamSocketProtocol(this, userToken);
- else if (flag == (byte)SocketFlag.Throughput)
- userToken.AsyncSocketInvokeElement = new ThroughputSocketProtocol(this, userToken);
- else if (flag == (byte)SocketFlag.Control)
- userToken.AsyncSocketInvokeElement = new ControlSocketProtocol(this, userToken);
- else if (flag == (byte)SocketFlag.LogOutput)
- userToken.AsyncSocketInvokeElement = new LogOutputSocketProtocol(this, userToken);
- if (userToken.AsyncSocketInvokeElement != null)
- {
- Program.Logger.InfoFormat("Building socket invoke element {0}.Local Address: {1}, Remote Address: {2}",
- userToken.AsyncSocketInvokeElement, userToken.ConnectSocket.LocalEndPoint, userToken.ConnectSocket.RemoteEndPoint);
- }
- }
SendCompleted用于回调下次需要发送的数据,具体实现过程如下:[csharp] view plain copy
- private bool ProcessSend(SocketAsyncEventArgs sendEventArgs)
- {
- AsyncSocketUserToken userToken = sendEventArgs.UserToken as AsyncSocketUserToken;
- if (userToken.AsyncSocketInvokeElement == null)
- return false;
- userToken.ActiveDateTime = DateTime.Now;
- if (sendEventArgs.SocketError == SocketError.Success)
- return userToken.AsyncSocketInvokeElement.SendCompleted(); //调用子类回调函数
- else
- {
- CloseClientSocket(userToken);
- return false;
- }
- }
当一个SocketAsyncEventArgs断开后,我们需要断开对应的Socket连接,并释放对应资源,具体实现函数如下:[csharp] view plain copy
- public virtual bool SendCompleted()
- {
- m_activeDT = DateTime.UtcNow;
- m_sendAsync = false;
- AsyncSendBufferManager asyncSendBufferManager = m_asyncSocketUserToken.SendBuffer;
- asyncSendBufferManager.ClearFirstPacket(); //清除已发送的包
- int offset = 0;
- int count = 0;
- if (asyncSendBufferManager.GetFirstPacket(ref offset, ref count))
- {
- m_sendAsync = true;
- return m_asyncSocketServer.SendAsyncEvent(m_asyncSocketUserToken.ConnectSocket, m_asyncSocketUserToken.SendEventArgs,
- asyncSendBufferManager.DynamicBufferManager.Buffer, offset, count);
- }
- else
- return SendCallback();
- }
- //发送回调函数,用于连续下发数据
- public virtual bool SendCallback()
- {
- return true;
- }
[csharp] view plain copy
- public void CloseClientSocket(AsyncSocketUserToken userToken)
- {
- if (userToken.ConnectSocket == null)
- return;
- string socketInfo = string.Format("Local Address: {0} Remote Address: {1}", userToken.ConnectSocket.LocalEndPoint,
- userToken.ConnectSocket.RemoteEndPoint);
- Program.Logger.InfoFormat("Client connection disconnected. {0}", socketInfo);
- try
- {
- userToken.ConnectSocket.Shutdown(SocketShutdown.Both);
- }
- catch (Exception E)
- {
- Program.Logger.ErrorFormat("CloseClientSocket Disconnect client {0} error, message: {1}", socketInfo, E.Message);
- }
- userToken.ConnectSocket.Close();
- userToken.ConnectSocket = null; //释放引用,并清理缓存,包括释放协议对象等资源
- m_maxNumberAcceptedClients.Release();
- m_asyncSocketUserTokenPool.Push(userToken);
- m_asyncSocketUserTokenList.Remove(userToken);
- }
3、SocketAsyncEventArgs封装和MSDN的不同点
MSDN在http://msdn.microsoft.com/zh-cn/library/system.NET.sockets.socketasynceventargs(v=vs.110).aspx实现了示例代码,并实现了初步的池化处理,我们是在它的基础上扩展实现了接收数据缓冲,发送数据队列,并把发送SocketAsyncEventArgs和接收SocketAsyncEventArgs分开,并实现了协议解析单元,这样做的好处是方便后续逻辑实现文件的上传,下载和日志输出。
DEMO下载地址:http://download.csdn.Net/detail/sqldebug_fan/7467745
免责声明:此代码只是为了演示C#完成端口编程,仅用于学习和研究,切勿用于商业用途。水平有限,C#也属于初学,错误在所难免,欢迎指正和指导。邮箱地址:fansheng_hx@163.com。
【转】C#高性能大容量SOCKET并发(二):SocketAsyncEventArgs封装