大宝版本IOCP封装类

      //////////////////////////////////////////////////
// IOCP.cpp文件

#include "iocp.h"
#pragma comment(lib, "WS2_32.lib")

CIOCPServer::CIOCPServer()
{
	// 列表
	m_pFreeBufferList = NULL;
	m_pFreeContextList = NULL;	
	m_pPendingAccepts = NULL;
	m_pConnectionList = NULL;

	m_nFreeBufferCount = 0;
	m_nFreeContextCount = 0;
	m_nPendingAcceptCount = 0;
	m_nCurrentConnection = 0;

	::InitializeCriticalSection(&m_FreeBufferListLock);
	::InitializeCriticalSection(&m_FreeContextListLock);
	::InitializeCriticalSection(&m_PendingAcceptsLock);
	::InitializeCriticalSection(&m_ConnectionListLock);

	// Accept请求
	m_hAcceptEvent = ::CreateEvent(NULL, FALSE, FALSE, NULL);
	m_hRepostEvent = ::CreateEvent(NULL, FALSE, FALSE, NULL);
	m_nRepostCount = 0;

	m_nPort = 4567;

	m_nInitialAccepts = 10;
	m_nInitialReads = 4;
	m_nMaxAccepts = 100;
	m_nMaxSends = 20;
	m_nMaxFreeBuffers = 200;
	m_nMaxFreeContexts = 100;
	m_nMaxConnections = 2000;

	m_hListenThread = NULL;
	m_hCompletion = NULL;
	m_sListen = INVALID_SOCKET;
	m_lpfnAcceptEx = NULL;
	m_lpfnGetAcceptExSockaddrs = NULL;

	m_bShutDown = FALSE;
	m_bServerStarted = FALSE;
	
	// 初始化WS2_32.dll
	WSADATA wsaData;
	WORD sockVersion = MAKEWORD(2, 2);
	::WSAStartup(sockVersion, &wsaData);
}

CIOCPServer::~CIOCPServer()
{
	Shutdown();

	if(m_sListen != INVALID_SOCKET)
		::closesocket(m_sListen);
	if(m_hListenThread != NULL)
		::CloseHandle(m_hListenThread);

	::CloseHandle(m_hRepostEvent);
	::CloseHandle(m_hAcceptEvent);

	::DeleteCriticalSection(&m_FreeBufferListLock);
	::DeleteCriticalSection(&m_FreeContextListLock);
	::DeleteCriticalSection(&m_PendingAcceptsLock);
	::DeleteCriticalSection(&m_ConnectionListLock);

	::WSACleanup();	
}


///////////////////////////////////
// 自定义帮助函数

CIOCPBuffer *CIOCPServer::AllocateBuffer(int nLen)
{
	CIOCPBuffer *pBuffer = NULL;
	if(nLen > BUFFER_SIZE)
		return NULL;

	// 为缓冲区对象申请内存
	::EnterCriticalSection(&m_FreeBufferListLock);
	if(m_pFreeBufferList == NULL)  // 内存池为空，申请新的内存
	{
		pBuffer = (CIOCPBuffer *)::HeapAlloc(GetProcessHeap(), 
						HEAP_ZERO_MEMORY, sizeof(CIOCPBuffer) + BUFFER_SIZE);
	}
	else	// 从内存池中取一块来使用
	{
		pBuffer = m_pFreeBufferList;
		m_pFreeBufferList = m_pFreeBufferList->pNext;	
		pBuffer->pNext = NULL;
		m_nFreeBufferCount --;
	}
	::LeaveCriticalSection(&m_FreeBufferListLock);

	// 初始化新的缓冲区对象
	if(pBuffer != NULL)
	{
		pBuffer->buff = (char*)(pBuffer + 1);
		pBuffer->nLen = nLen;
	}
	return pBuffer;
}

void CIOCPServer::ReleaseBuffer(CIOCPBuffer *pBuffer)
{
	::EnterCriticalSection(&m_FreeBufferListLock);

	if(m_nFreeBufferCount <= m_nMaxFreeBuffers)	// 将要释放的内存添加到空闲列表中
	{
		memset(pBuffer, 0, sizeof(CIOCPBuffer) + BUFFER_SIZE);
		pBuffer->pNext = m_pFreeBufferList;
		m_pFreeBufferList = pBuffer;

		m_nFreeBufferCount ++ ;
	}
	else			// 已经达到最大值，真正的释放内存
	{
		::HeapFree(::GetProcessHeap(), 0, pBuffer);
	}
	::LeaveCriticalSection(&m_FreeBufferListLock);
}


CIOCPContext *CIOCPServer::AllocateContext(SOCKET s)
{
	CIOCPContext *pContext;

	// 申请一个CIOCPContext对象
	::EnterCriticalSection(&m_FreeContextListLock);
	if(m_pFreeContextList == NULL)
	{
		pContext = (CIOCPContext *)
				::HeapAlloc(::GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(CIOCPContext)); 

		::InitializeCriticalSection(&pContext->Lock);
	}
	else	
	{
		// 在空闲列表中申请
		pContext = m_pFreeContextList;
		m_pFreeContextList = m_pFreeContextList->pNext;
		pContext->pNext = NULL;

		m_nFreeContextCount --;
	}
	::LeaveCriticalSection(&m_FreeContextListLock);

	// 初始化对象成员
	if(pContext != NULL)
	{
		pContext->s = s;
		pContext->lpBufBegin = pContext->lpBufEnd = pContext->arrayDataBuf;
	}
	return pContext;
}

void CIOCPServer::ReleaseContext(CIOCPContext *pContext)
{
	if(pContext->s != INVALID_SOCKET)
		::closesocket(pContext->s);

	// 首先释放（如果有的话）此套节字上的没有按顺序完成的读I/O的缓冲区
	CIOCPBuffer *pNext;
	while(pContext->pOutOfOrderReads != NULL)
	{
		pNext = pContext->pOutOfOrderReads->pNext;
		ReleaseBuffer(pContext->pOutOfOrderReads);
		pContext->pOutOfOrderReads = pNext;
	}

	::EnterCriticalSection(&m_FreeContextListLock);
	
	if(m_nFreeContextCount <= m_nMaxFreeContexts) // 添加到空闲列表
	{
		// 先将关键代码段变量保存到一个临时变量中
		CRITICAL_SECTION cstmp = pContext->Lock;
		// 将要释放的上下文对象初始化为0
		memset(pContext, 0, sizeof(CIOCPContext));

		// 再放会关键代码段变量，将要释放的上下文对象添加到空闲列表的表头
		pContext->Lock = cstmp;
		pContext->pNext = m_pFreeContextList;
		m_pFreeContextList = pContext;
		
		// 更新计数
		m_nFreeContextCount ++;
	}
	else
	{
		::DeleteCriticalSection(&pContext->Lock);
		::HeapFree(::GetProcessHeap(), 0, pContext);
	}

	::LeaveCriticalSection(&m_FreeContextListLock);
}

void CIOCPServer::FreeBuffers()
{
	// 遍历m_pFreeBufferList空闲列表，释放缓冲区池内存
	::EnterCriticalSection(&m_FreeBufferListLock);

	CIOCPBuffer *pFreeBuffer = m_pFreeBufferList;
	CIOCPBuffer *pNextBuffer;
	while(pFreeBuffer != NULL)
	{
		pNextBuffer = pFreeBuffer->pNext;
		if(!::HeapFree(::GetProcessHeap(), 0, pFreeBuffer))
		{
#ifdef _DEBUG
			::OutputDebugString("  FreeBuffers释放内存出错！");
#endif // _DEBUG
			break;
		}
		else
		{
#ifdef _DEBUG
			OutputDebugString("  FreeBuffers释放内存！");
#endif // _DEBUG
		}

		pFreeBuffer = pNextBuffer;
	}
	m_pFreeBufferList = NULL;
	m_nFreeBufferCount = 0;

	::LeaveCriticalSection(&m_FreeBufferListLock);
}

void CIOCPServer::FreeContexts()
{
	// 遍历m_pFreeContextList空闲列表，释放缓冲区池内存
	::EnterCriticalSection(&m_FreeContextListLock);
	
	CIOCPContext *pFreeContext = m_pFreeContextList;
	CIOCPContext *pNextContext;
	while(pFreeContext != NULL)
	{
		pNextContext = pFreeContext->pNext;
		
		::DeleteCriticalSection(&pFreeContext->Lock);
		if(!::HeapFree(::GetProcessHeap(), 0, pFreeContext))
		{
#ifdef _DEBUG
			::OutputDebugString("  FreeContexts释放内存出错！");
#endif // _DEBUG
			break;
		}
		else
		{
#ifdef _DEBUG
			OutputDebugString("  FreeContexts释放内存！\r\n");
#endif // _DEBUG
		}
		pFreeContext = pNextContext;
	}
	m_pFreeContextList = NULL;
	m_nFreeContextCount = 0;

	::LeaveCriticalSection(&m_FreeContextListLock);
}


BOOL CIOCPServer::AddAConnection(CIOCPContext *pContext)
{
	// 向客户连接列表添加一个CIOCPContext对象

	::EnterCriticalSection(&m_ConnectionListLock);
	if(m_nCurrentConnection <= m_nMaxConnections)
	{
		// 添加到表头
		pContext->pNext = m_pConnectionList;
		m_pConnectionList = pContext;
		// 更新计数
		m_nCurrentConnection ++;

		::LeaveCriticalSection(&m_ConnectionListLock);
		return TRUE;
	}
	::LeaveCriticalSection(&m_ConnectionListLock);

	return FALSE;
}

void CIOCPServer::CloseAConnection(CIOCPContext *pContext)
{
	// 首先从列表中移除要关闭的连接
	::EnterCriticalSection(&m_ConnectionListLock);

	CIOCPContext* pTest = m_pConnectionList;
	if(pTest == pContext)
	{
		m_pConnectionList =  pContext->pNext;
		m_nCurrentConnection --;
	}
	else
	{
		while(pTest != NULL && pTest->pNext !=  pContext)
			pTest = pTest->pNext;
		if(pTest != NULL)
		{
			pTest->pNext =  pContext->pNext;
			m_nCurrentConnection --;
		}
	}
	
	::LeaveCriticalSection(&m_ConnectionListLock);

	// 然后关闭客户套节字
	::EnterCriticalSection(&pContext->Lock);

	if(pContext->s != INVALID_SOCKET)
	{
		::closesocket(pContext->s);	
		pContext->s = INVALID_SOCKET;
	}
	pContext->bClosing = TRUE;

	::LeaveCriticalSection(&pContext->Lock);
}

void CIOCPServer::CloseAllConnections()
{
	// 遍历整个连接列表，关闭所有的客户套节字

	::EnterCriticalSection(&m_ConnectionListLock);

	CIOCPContext *pContext = m_pConnectionList;
	while(pContext != NULL)
	{	
		::EnterCriticalSection(&pContext->Lock);

		if(pContext->s != INVALID_SOCKE