Start函数用于开启服务

1 初始化状态变量

2 创建监听套接字

3 加载使用扩展API函数

4 创建完成端口对象

5 建立监听套接字和完成端口对象间的关联

6 为监听套接字注册FD_ACCEPT时间

7 投递AcceptEx IO不够时可以得到通知后创建监听线程

BOOL CIOCOPServer::Start(int nPort,int nMaxConnnections,int nMaxFreeBuffers,int nMaxFreeContexts,int nInitialReads){    //检查服务是否启动    if(m_bServerStarted)        return FALSE;    //保存参数    m_nPort = nPort;    m_nMaxConnnections = nMaxConnnections;    m_nMaxFreeBuffers = nMaxFreeBuffers;    m_nMaxFreeContexts = nMaxFreeContexts;    m_nInitialReads = nInitialReads;    //初始化变量    m_bServerStarted = TRUE;    m_bShutDown = FALSE;    //创建监听套接字，绑定到本地端口， 进入监听模式    m_sListen = ::WSASocket(AF_INET,SOCK_STREAM,0,NULL,0,WSA_FLAG_OVERLAPPED);    SOCKADDR_IN si;    si.sin_family = AF_INET;    si.sin_port = nPort;    si.sin_addr.S_un.S_addr = INADDR_ANY;    if(::bind(m_sListen,(sockaddr*)&si,sizeof(si))==SOCKET_ERROR)    {        m_bServerStarted = FALSE;        return FALSE;    }    ::listen(m_sListen,200);    //创建完成端口    m_hConnection = ::CreateIoCompletionPort(INVALID_HANDLE_VALUE,0,0,0);    //加载扩展函数AcceptEx    GUID GuidAcceptEx = WSAID_ACCEPTEX;    DWORD dwBytes;    WSAIotcl(         m_sListen,         SIO_GET_EXTENSION_FUNCTION_POINTER,         &GuidAcceptEx,         sizeof(GuidAcceptEx),         &m_lpfnAcceptEx,         sizeof(m_lpfnAcceptEx),         &dwBytes,         NULL,         NULL         );    //加载GetAcceptExSockaddrs    GUID GuidAcceptExSockaddrs = WSAID_GETACCEPTEXSOCKADDRS;    ::WSAIoctl(m_sListen,            SIO_GET_EXTENSION_FUNCTION_POINTER,            &GuiGetAcceptExSockaddrs,            sizeof(GuidGetAcceptExSockaddrs),            &m_lpfnAcceptExSockaddrs,            sizeof(m_lofnAcceptExSockaddrs),            &dwBytes,            NULL,            NULL);    //将监听套接字关联到完成端口    ::CreateIoCompletionPort((HANDLE)m_sListen,m_hConnection,(DWORD)0,0);    //注册FD_ACCEPT事件    WSAEventSelect(m_sListen,m_hAcceptEvent,FD_ACCEPT);    //创建监听线程    m_hListenThread = ::CreateThread(NULL,0,_ListenThreadProc,this,0,NULL);    return TRUE;}

监听线程_ListenThreadProc主要责任：监听套接字投递AcceptEx IO请求。

m_hAcceptEvent:当winsock接收到新的连接请求，但是AcceptEx IO,请求来接收这个连接时，就会触发该时间对象。

m_hRepostEvent：与IO进行交互。

_ListenThreadProc在下面3中情况下投递Accept请求：

1 程序初始化，要先投递几个Accept请求，个数由用户指定

2 处理IO的线程接受到一个客户，使m_hRepostEvent时间受信，_ListenThreadProc线程得到通知后再投递一个Accept请求。

3 程序运行期间，如果投递的Accept请求不够用，用户的连接请求未能够马上处理，这时候再投递若干个Accept请求。

DWORD WINAPI CIOCPServer::_ListenThreadProc(LPVOID lpParam){    CIOCPServer *pThis = (CIOCPServer*)lpParam;    //在监听套接字上投递几个AcceptIO    CIOCPBuffer *pBuffer;    for(int i=0;i
     
      m_nInitialAccepts;i++)    {        pBuffer = pThis->AllocateBuffer(BUFFER_SIZE);        if(pBuffer==NULL)            return -1;        pTHis->InsertPendingAccept(pBuffer);        pThis->PostAccept(pBuffer);    }    //构建事件对象数组    HANDLE hWaitEvents[2+MAX_THREAD];    int nEventCount = 0;    hWaitEvents[nEventCount++]=pThis->m_hAcceptEvent;    hWaitEvents[nEventCount++]=pThis->m_hRepostEvent;    //创建指定数量的工作线程在完成端口上处理IO    for(i=0;i
      
       m_bShutDown || nIndex==WSA_WAIT_FAILED)        {            //关闭所有连接            pThis->CloseAllConnections();            ::Sleep(0);            //关闭监听套接字            ::closesocket(pThis->m_sListen);            pThis->m_sListen=INVALID_SOCKET;            ::Sleep(0);            //通知所有IO处理线程退出            for(int i=2;i
       
        m_hCompletion,-1,0,NULL);            }            //等待IO处理线程退出            ::WaitForMultipleObjects(MAX_THREAD,&hWaitEvents[2],TRUE,5*1000);            for(i=2;i
        
         m_hCompletion);            pThis->FreeBuffers();            pThis->FreeContexts();            ::ExitThread(0);        }        //定时检查所有未返回的AcceptEx IO的连接建立多长时间        if(nIndex == WSA_WAIT_TIMEOUT)        {            pBuffer = pThis->m_pPendingAccepts;            while(pBuffer!=NULL)            {                int nSeconds;                int nLen = sizeof(nSeconds);                //取得连接建立时间                ::getsockopt(pBuffer->sClient,SOL_SOCKET,SO_CONNECT_TIME,(char*)&nSeconds,&nLen);                //如果超过两分钟，就丢弃                if(nSeconds!=-1 && nSeconds>=2*60)                {                    closesocket(pBuffer->sClient);                    pBuffer->sClient = INVALIDE_SOCKET;                }                pBuffer = pBuffer->pNext;            }        }        else        {            nIndex = nIndex-WAIT_OBJECT_0;            WSANETWORKEVENTS ne;            int nLimit=0;            if(nIndex==0)//m_hAcceptEvent时间对象受信，说明投递的Accept请求不够，需要增加            {                ::WSAEnumNetworkEvents(pThis->m_sListen,hWaitEvents[nIndex],&ne);                if(ne.lNetworkEvents & FD_ACCEPT)                {                    nLimit = 50;                }            }            else if(nIndex==1)//m_hRepostEvent事件对象受信，说明处理IO的线程接受到新的客户            {                nLimit = InterlockedExchange(&pThis->m_nRepostCount,0);            }            else if(nIndex>1)//IO服务线程退出，说明有错误发生，关闭服务器            {                pThis->m_bShutDown = TRUE;                continue;            }            //投递nLimit个AcceptEx IO 请求            int i=0;            while(i++ < nLimit && pThis->m_nPendingAcceptCount < pThis->m_nMaxAccepts)            {                pBuffer = pThis->AllocateBuffer(BUFFER_SIZE);                if(pBuffer!=NULL)                {                    pThis->InsertPendingAccept(pBuffer);                    pThis->PostAccept(pBuffer);                }            }        }            }    return 0;}
        
       
      
     

 

 3 停止服务函数ShutDown

void CIOCPServer::ShutDown(){    if(!m_bServerStarted)        return;    //通知监听线程，马上停止服务    m_bShutDown = TRUE;    ::SetEvent(m_hAcceptEvent);    //等待监听线程退出    ::WaitForSingleObject(m_hListenThread,INFINITE);    ::CloseHandle(m_hListenThread);    m_hListenThread = NUll;    m_bServerStarted = FALSE;}