一个简单的IOCP服务器实例

//////////////////////////////////////////////////////////
// initsock.h文件

#include <winsock2.h>
#pragma comment(lib, "WS2_32")	// 链接到WS2_32.lib

class CInitSock
{
public:
CInitSock(BYTE minorVer = 2, BYTE majorVer = 2)
{
// 初始化WS2_32.dll
WSADATA wsaData;
WORD sockVersion = MAKEWORD(minorVer, majorVer);
if(::WSAStartup(sockVersion, &wsaData) != 0)
{
exit(0);
}
}
~CInitSock()
{
::WSACleanup();
}
};

/////////////////////////////////////////////////
// IOCPDemo.cpp文件			调试通过

#include "initsock.h"
#include <stdio.h>
#include <windows.h>

// 初始化Winsock库
CInitSock theSock;

#define BUFFER_SIZE 1024

typedef struct _PER_HANDLE_DATA		// per-handle数据
{
SOCKET s;			// 对应的套节字句柄
sockaddr_in addr;	// 客户方地址
} PER_HANDLE_DATA, *PPER_HANDLE_DATA;

typedef struct _PER_IO_DATA			// per-I/O数据
{
OVERLAPPED ol;			// 重叠结构
char buf[BUFFER_SIZE];	// 数据缓冲区
int nOperationType;		// 操作类型
#define OP_READ   1
#define OP_WRITE  2
#define OP_ACCEPT 3
} PER_IO_DATA, *PPER_IO_DATA;

DWORD WINAPI ServerThread(LPVOID lpParam)
{
// 得到完成端口对象句柄
HANDLE hCompletion = (HANDLE)lpParam;

DWORD dwTrans;
PPER_HANDLE_DATA pPerHandle;
PPER_IO_DATA pPerIO;
while(TRUE)
{
// 在关联到此完成端口的所有套节字上等待I/O完成
BOOL bOK = ::GetQueuedCompletionStatus(hCompletion,
&dwTrans, (LPDWORD)&pPerHandle, (LPOVERLAPPED*)&pPerIO, WSA_INFINITE);
if(!bOK)						// 在此套节字上有错误发生
{
::closesocket(pPerHandle->s);
::GlobalFree(pPerHandle);
::GlobalFree(pPerIO);
continue;
}

if(dwTrans == 0 &&				// 套节字被对方关闭
(pPerIO->nOperationType == OP_READ || pPerIO->nOperationType == OP_WRITE))

{
::closesocket(pPerHandle->s);
::GlobalFree(pPerHandle);
::GlobalFree(pPerIO);
continue;
}

switch(pPerIO->nOperationType)	// 通过per-I/O数据中的nOperationType域查看什么I/O请求完成了
{
case OP_READ:	// 完成一个接收请求
{
static int count=1;
pPerIO->buf[dwTrans] = '\0';
//printf(pPerIO -> buf);
printf("第%d次接收到数据为:%s\n",count++,pPerIO->buf);

// 继续投递接收I/O请求
WSABUF buf;
buf.buf = pPerIO->buf ;
buf.len = BUFFER_SIZE;
pPerIO->nOperationType = OP_READ;

DWORD nFlags = 0;
::WSARecv(pPerHandle->s, &buf, 1, &dwTrans, &nFlags, &pPerIO->ol, NULL);
}
break;
case OP_WRITE: // 本例中没有投递这些类型的I/O请求
case OP_ACCEPT:
break;
}
}
return 0;
}

void main()
{
int nPort = 9090;
// 创建完成端口对象，创建工作线程处理完成端口对象中事件
HANDLE hCompletion = ::CreateIoCompletionPort(INVALID_HANDLE_VALUE, 0, 0, 0);

SYSTEM_INFO siSys;
//获取CPU数目
GetSystemInfo(&siSys);
//创建一定数目的工作者线程，本例中以一个处理器一个线程搭配
for(int i = 0; i<(int)siSys.dwNumberOfProcessors*2; i++)//NumberOfProcessors
{
::CreateThread(NULL, 0, ServerThread, (LPVOID)hCompletion, 0, 0);
}

// 创建监听套节字，绑定到本地地址，开始监听
SOCKET sListen = ::socket(AF_INET, SOCK_STREAM, 0);
SOCKADDR_IN si;
si.sin_family = AF_INET;
si.sin_port = ::ntohs(nPort);
si.sin_addr.S_un.S_addr = INADDR_ANY;
::bind(sListen, (sockaddr*)&si, sizeof(si));
::listen(sListen, 5);

// 循环处理到来的连接
while(TRUE)
{
// 等待接受未决的连接请求
SOCKADDR_IN saRemote;
int nRemoteLen = sizeof(saRemote);
SOCKET sNew = ::accept(sListen, (sockaddr*)&saRemote, &nRemoteLen);

// 接受到新连接之后，为它创建一个per-handle数据，并将它们关联到完成端口对象。
PPER_HANDLE_DATA pPerHandle =
(PPER_HANDLE_DATA)::GlobalAlloc(GPTR, sizeof(PER_HANDLE_DATA));
pPerHandle->s = sNew;
memcpy(&pPerHandle->addr, &saRemote, nRemoteLen);
::CreateIoCompletionPort((HANDLE)pPerHandle->s, hCompletion, (DWORD)pPerHandle, 0);

// 投递一个接收请求
PPER_IO_DATA pPerIO = (PPER_IO_DATA)::GlobalAlloc(GPTR, sizeof(PER_IO_DATA));
pPerIO->nOperationType = OP_READ;
WSABUF buf;
buf.buf = pPerIO->buf;
buf.len = BUFFER_SIZE;
DWORD dwRecv;
DWORD dwFlags = 0;
::WSARecv(pPerHandle->s, &buf, 1, &dwRecv, &dwFlags, &pPerIO->ol, NULL);
}
}