////////////////////////////////////////////////////////////////////////////////
//
// FUNCTION: CIOCPServer::OnAccept
//
// DESCRIPTION: Listens for incoming clients
//
// INPUTS:
//
// NOTES:
//
// MODIFICATIONS:
//
// Name Date Version Comments
// N T ALMOND 06042001 1.0 Origin
// Ulf Hedlund 09072001 Changes for OVERLAPPEDPLUS
////////////////////////////////////////////////////////////////////////////////
void CIOCPServer::OnAccept()
{
SOCKADDR_IN SockAddr;
SOCKET clientSocket;
int nRet;
int nLen;
if (m_bTimeToKill || m_bDisconnectAll)
return;
//
// accept the new socket descriptor
//
nLen = sizeof(SOCKADDR_IN);
clientSocket = accept(m_socListen,
(LPSOCKADDR)&SockAddr,
&nLen);
if (clientSocket == SOCKET_ERROR)
{
nRet = WSAGetLastError();
if (nRet != WSAEWOULDBLOCK)
{
//
// Just log the error and return
//
TRACE(_T("accept() error\n"),WSAGetLastError());
return;
}
}
// Create the Client context to be associted with the completion port
ClientContext* pContext = AllocateContext();
// AllocateContext fail
if (pContext == NULL)
return;
pContext->m_Socket = clientSocket;
// Fix up In Buffer
pContext->m_wsaInBuffer.buf = (char*)pContext->m_byInBuffer;
pContext->m_wsaInBuffer.len = sizeof(pContext->m_byInBuffer);
// Associate the new socket with a completion port.
if (!AssociateSocketWithCompletionPort(clientSocket, m_hCompletionPort, (DWORD) pContext))
{
delete pContext;
pContext = NULL;
closesocket( clientSocket );
closesocket( m_socListen );
return;
}
// 关闭nagle算法,以免影响性能，因为控制时控制端要发送很多数据量很小的数据包,要求马上发送
// 暂不关闭，实验得知能网络整体性能有很大影响
const char chOpt = 1;
// int nErr = setsockopt(pContext->m_Socket, IPPROTO_TCP, TCP_NODELAY, &chOpt, sizeof(char));
// if (nErr == -1)
// {
// TRACE(_T("setsockopt() error\n"),WSAGetLastError());
// return;
// }
// Set KeepAlive 开启保活机制
if (setsockopt(pContext->m_Socket, SOL_SOCKET, SO_KEEPALIVE, (char *)&chOpt, sizeof(chOpt)) != 0)
{
TRACE(_T("setsockopt() error\n"), WSAGetLastError());
}
// 设置超时详细信息
tcp_keepalive klive;
klive.onoff = 1; // 启用保活
klive.keepalivetime = m_nKeepLiveTime;
klive.keepaliveinterval = 1000 * 10; // 重试间隔为10秒 Resend if No-Reply
WSAIoctl
(
pContext->m_Socket,
SIO_KEEPALIVE_VALS,
&klive,
sizeof(tcp_keepalive),
NULL,
0,
(unsigned long *)&chOpt,
0,
NULL
);
CLock cs(m_cs, "OnAccept" );
// Hold a reference to the context
m_listContexts.AddTail(pContext);
// Trigger first IO Completion Request
// Otherwise the Worker thread will remain blocked waiting for GetQueuedCompletionStatus...
// The first message that gets queued up is ClientIoInitializing - see ThreadPoolFunc and
// IO_MESSAGE_HANDLER
OVERLAPPEDPLUS *pOverlap = new OVERLAPPEDPLUS(IOInitialize);
PostQueuedCompletionStatusT pPostQueuedCompletionStatus=(PostQueuedCompletionStatusT)GetProcAddress(LoadLibrary("KERNEL32.dll"),"PostQueuedCompletionStatus");
BOOL bSuccess = pPostQueuedCompletionStatus(m_hCompletionPort, 0, (DWORD) pContext, &pOverlap->m_ol);
if ( (!bSuccess && GetLastError( ) != ERROR_IO_PENDING))
{
RemoveStaleClient(pContext,TRUE);
return;
}
m_pNotifyProc((LPVOID) m_pFrame, pContext, NC_CLIENT_CONNECT);
// Post to WSARecv Next
PostRecv(pContext);
}
void CIOCPServer::HandleIO(DWORD dwKey, CIOCPBuffer *pBuffer, DWORD dwTrans, int nError)
{
CIOCPContext *pContext = (CIOCPContext *)dwKey;
#ifdef _DEBUG
// ::OutputDebugString(" HandleIO... \n");
#endif // _DEBUG
// 1）首先减少套节字上的未决I/O计数
if(pContext != NULL)
{
::EnterCriticalSection(&pContext->Lock);
if(pBuffer->nOperation == OP_READ)
pContext->nOutstandingRecv --;
else if(pBuffer->nOperation == OP_WRITE)
pContext->nOutstandingSend --;
::LeaveCriticalSection(&pContext->Lock);
// 2）检查套节字是否已经被我们关闭
if(pContext->bClosing)
{
#ifdef _DEBUG
::OutputDebugString(" pContext->bClosing 检查到套节字已经被我们关闭 \n");
#endif // _DEBUG
if(pContext->nOutstandingRecv == 0 && pContext->nOutstandingSend == 0)
{
ReleaseContext(pContext);
}
// 释放已关闭套节字的未决I/O
ReleaseBuffer(pBuffer);
return;
}
}
else
{
RemovePendingAccept(pBuffer);
#ifdef _DEBUG
::OutputDebugString("RemovePendingAccept 检查到套节字连接超时未完成被我们关闭 \n");
#endif // _DEBUG
}
// 3）检查套节字上发生的错误，如果有的话，通知用户，然后关闭套节字
if(nError != NO_ERROR)
{
if(pBuffer->nOperation != OP_ACCEPT)
{
OnConnectionError(pContext, pBuffer, nError);
CloseAConnection(pContext);
if(pContext->nOutstandingRecv == 0 && pContext->nOutstandingSend == 0)
{
ReleaseContext(pContext);
}
#ifdef _DEBUG
::OutputDebugString("nError 非OP_ACCEPT检查到客户套节字上发生错误 \n");
#endif // _DEBUG
}
else // 在监听套节字上发生错误，也就是监听套节字处理的客户出错了
{
// 客户端出错，释放I/O缓冲区
if(pBuffer->sClient != INVALID_SOCKET)
{
::closesocket(pBuffer->sClient);
pBuffer->sClient = INVALID_SOCKET;
}
#ifdef _DEBUG
::OutputDebugString("nError Listen SOCKET检查到监听套节字上发生错误 \n");
#endif // _DEBUG
}
ReleaseBuffer(pBuffer);
return;
}
// 开始处理
if(pBuffer->nOperation == OP_ACCEPT)
{
if(dwTrans == 0)
{
#ifdef _DEBUG
::OutputDebugString("OP_ACCEPT 监听套节字上客户端关闭 \n");
#endif // _DEBUG
if(pBuffer->sClient != INVALID_SOCKET)
{
::closesocket(pBuffer->sClient);
pBuffer->sClient = INVALID_SOCKET;
}
}
else
{
// 为新接受的连接申请客户上下文对象
CIOCPContext *pClient = AllocateContext(pBuffer->sClient);
if(pClient != NULL)
{
if(AddAConnection(pClient))
{
// 取得客户地址
int nLocalLen, nRmoteLen;
LPSOCKADDR pLocalAddr, pRemoteAddr;
m_lpfnGetAcceptExSockaddrs(
pBuffer->buff,
pBuffer->nLen - ((sizeof(sockaddr_in) + 16) * 2),
sizeof(sockaddr_in) + 16,
sizeof(sockaddr_in) + 16,
(SOCKADDR **)&pLocalAddr,
&nLocalLen,
(SOCKADDR **)&pRemoteAddr,
&nRmoteLen);
memcpy(&pClient->addrLocal, pLocalAddr, nLocalLen);
memcpy(&pClient->addrRemote, pRemoteAddr, nRmoteLen);
// 关联新连接到完成端口对象
::CreateIoCompletionPort((HANDLE)pClient->s, m_hCompletion, (DWORD)pClient, 0);
// 通知用户
pBuffer->nLen = dwTrans;
OnConnectionEstablished(pClient, pBuffer);
// 向新连接投递几个Read请求，这些空间在套节字关闭或出错时释放
for(int i=0; i<m_nInitialReads ; i++)
{
CIOCPBuffer *p = AllocateBuffer(BUFFER_SIZE);
if(p != NULL)
{
if(!PostRecv(pClient, p))
{
CloseAConnection(pClient);
break;
}
}
}
}
else // 连接数量已满，关闭连接
{
CloseAConnection(pClient);
ReleaseContext(pClient);
}
}
else
{
// 资源不足，关闭与客户的连接即可
::closesocket(pBuffer->sClient);
pBuffer->sClient = INVALID_SOCKET;
}
}
// Accept请求完成，释放I/O缓冲区
ReleaseBuffer(pBuffer);
// 通知监听线程继续再投递一个Accept请求
::InterlockedIncrement(&m_nRepostCount);
::SetEvent(m_hRepostEvent);
}
else if(pBuffer->nOperation == OP_READ)
{
if(dwTrans == 0) // 对方关闭套节字
{
// 先通知用户
pBuffer->nLen = 0;
OnConnectionClosing(pContext, pBuffer);
// 再关闭连接
CloseAConnection(pContext);
// 释放客户上下文和缓冲区对象
if(pContext->nOutstandingRecv == 0 && pContext->nOutstandingSend == 0)
{
ReleaseContext(pContext);
}
ReleaseBuffer(pBuffer);
}
else
{
pBuffer->nLen = dwTrans;
// 按照I/O投递的顺序读取接收到的数据
CIOCPBuffer *p = GetNextReadBuffer(pContext, pBuffer);
while(p != NULL)
{
// 通知用户
OnReadCompleted(pContext, p);
// 增加要读的序列号的值
::InterlockedIncrement((LONG*)&pContext->nCurrentReadSequence);
// 释放这个已完成的I/O
ReleaseBuffer(p);
p = GetNextReadBuffer(pContext, NULL);
}
// printf("空闲buffer数:%d \n",m_nFreeBufferCount);
if (pContext->nOutstandingRecv <= 0)
{
for(int i=0; i<m_nInitialReads ; i++)
{
// 继续投递几个新的重叠接收请求,这样能达到最快速度
// 因为此时pBuffer已经释放或被保存到缓冲区,所以分配一个新的
pBuffer = AllocateBuffer(BUFFER_SIZE);
if(pBuffer != NULL)
{
if(!PostRecv(pContext, pBuffer))
{
CloseAConnection(pContext);
break;
}
}
}
}
}
}
else if(pBuffer->nOperation == OP_WRITE)
{
if(dwTrans == 0) // 对方关闭套节字
{
// 先通知用户
pBuffer->nLen = 0;
OnConnectionClosing(pContext, pBuffer);
// 再关闭连接
CloseAConnection(pContext);
// 释放客户上下文和缓冲区对象
if(pContext->nOutstandingRecv == 0 && pContext->nOutstandingSend == 0)
{
ReleaseContext(pContext);
}
ReleaseBuffer(pBuffer);
}
else
{
// 写操作完成，通知用户
pBuffer->nLen = dwTrans;
OnWriteCompleted(pContext, pBuffer);
// 释放SendText函数申请的缓冲区
ReleaseBuffer(pBuffer);
}
}
}