转自于：http://hi.baidu.com/netpet/blog/item/bb5ebdb7fd4650f030add1a1.html
代码如下，注释已经全部改成中文
#include <winsock2.h>
//#include <windows.h>
#include <stdio.h>
#define PORT 5150
#define DATA_BUFSIZE 8192
typedef struct
{
OVERLAPPED Overlapped;
WSABUF DataBuf;
CHAR Buffer[DATA_BUFSIZE];
DWORD BytesSEND;
DWORD BytesRECV;
} PER_IO_OPERATION_DATA, * LPPER_IO_OPERATION_DATA;
typedef struct
{
SOCKET Socket;
} PER_HANDLE_DATA, * LPPER_HANDLE_DATA;
DWORD WINAPI ServerWorkerThread(LPVOID CompletionPortID);
int main(void)
{
SOCKADDR_IN InternetAddr;
SOCKET Listen;
SOCKET Accept;
HANDLE CompletionPort;
SYSTEM_INFO SystemInfo;
LPPER_HANDLE_DATA PerHandleData;
LPPER_IO_OPERATION_DATA PerIoData;
int i;
DWORD RecvBytes;
DWORD Flags;
DWORD ThreadID;
WSADATA wsaData;
DWORD Ret;
if ((Ret = WSAStartup(0x0202, &wsaData)) != 0)
{
printf("WSAStartup失败了，错误信息如下: %d\n", Ret);
return;
}
// 设置一个I/O完成端口.
if ((CompletionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0)) == NULL)
{
printf( "CreateIoCompletionPort 失败了，错误信息如下: %d\n", GetLastError());
return;
}
// 测试系统中有多少cpu处理器
GetSystemInfo(&SystemInfo);
// 基于系统可用的处理器创建工作线程，为每个处理器创建连个线程
for(i = 0; i < SystemInfo.dwNumberOfProcessors * 2; i++)
{
HANDLE ThreadHandle;
// 创建一个服务端线程并且传递一个完成端口给这个线程.
if ((ThreadHandle = CreateThread(NULL, 0, ServerWorkerThread, CompletionPort,
0, &ThreadID)) == NULL)
{
printf("CreateThread()发生了如下错误： %d\n", GetLastError());
return;
}
else
{printf("创建了一个完成端口.\n");
}
// 关闭 thread句柄
CloseHandle(ThreadHandle);
}
// 创建一个监听套接字
if ((Listen =WSASocket(AF_INET, SOCK_STREAM, 0, NULL,0,WSA_FLAG_OVERLAPPED)) == INVALID_SOCKET)
{
printf("WSASocket() 发生了如下错误： %d\n", WSAGetLastError());
return;
}
else
{printf("创建监听套接字成功\n");}
InternetAddr.sin_family = AF_INET;
InternetAddr.sin_addr.s_addr = htonl(INADDR_ANY);
InternetAddr.sin_port = htons(PORT);
if (bind(Listen, (PSOCKADDR) &InternetAddr, sizeof(InternetAddr)) == SOCKET_ERROR)
{
printf("bind()端口或IP时发生了如下错误： %d\n", WSAGetLastError());
return;
}
else
{printf("绑定端口%d成功\n",PORT);}
// 准备socket 用来监听
if (listen(Listen, 5) == SOCKET_ERROR)
{
printf("listen() 发生了如下错误 %d\n", WSAGetLastError());
return;
}
else
{printf("预处理成功，开始在端口 %d 处监听...\n",PORT);}
//接受连接并且交给完成端口处理
while(TRUE)
{
if ((Accept = WSAAccept(Listen, NULL, NULL, NULL, 0)) == SOCKET_ERROR)
{
printf("WSAAccept() 发生了如下错误： %d\n", WSAGetLastError());
return;
}
// 创建一个套接字信息结构体去联系起来socket
if ((PerHandleData = (LPPER_HANDLE_DATA) GlobalAlloc(GPTR,
sizeof(PER_HANDLE_DATA))) == NULL)
{
printf("GlobalAlloc() 发生了如下错误： %d\n", GetLastError());
return;
}
// 将接受到的套接字与原始的完成端口联系起来.
printf("号码为 %d 的socket连接上了\n", Accept);
PerHandleData->Socket = Accept;
if (CreateIoCompletionPort((HANDLE) Accept, CompletionPort, (DWORD) PerHandleData,
0) == NULL)
{
printf("CreateIoCompletionPort 发生了如下错误： %d\n", GetLastError());
return;
}
// 创建每一个I/O 套接字信息结构体去和下面被调用的 to associate with the
// WSARecv 连接.
if ((PerIoData = (LPPER_IO_OPERATION_DATA) GlobalAlloc(GPTR, sizeof(PER_IO_OPERATION_DATA))) == NULL)
{
printf("GlobalAlloc() 发生了如下错误： %d\n", GetLastError());
return;
}
else{printf("接收了一个连接\n");}
ZeroMemory(&(PerIoData->Overlapped), sizeof(OVERLAPPED));
PerIoData->BytesSEND = 0;
PerIoData->BytesRECV = 0;
PerIoData->DataBuf.len = DATA_BUFSIZE;
PerIoData->DataBuf.buf = PerIoData->Buffer;
Flags = 0;
if (WSARecv(Accept, &(PerIoData->DataBuf), 1, &RecvBytes, &Flags,
&(PerIoData->Overlapped), NULL) == SOCKET_ERROR)
{
if (WSAGetLastError() != ERROR_IO_PENDING)
{
printf("WSARecv() 发生了如下错误： %d\n", WSAGetLastError());
return;
}
}
}
}
DWORD WINAPI ServerWorkerThread(LPVOID CompletionPortID)
{
HANDLE CompletionPort = (HANDLE) CompletionPortID;
DWORD BytesTransferred;
LPOVERLAPPED Overlapped;
LPPER_HANDLE_DATA PerHandleData;
LPPER_IO_OPERATION_DATA PerIoData;
DWORD SendBytes, RecvBytes;
DWORD Flags;
while(TRUE)
{
if (GetQueuedCompletionStatus(CompletionPort, &BytesTransferred,
(LPDWORD)&PerHandleData, (LPOVERLAPPED *) &PerIoData, INFINITE) == 0)
{
printf("GetQueuedCompletionStatus 发生了如下错误： %d\n", GetLastError());
return 0;
}
//首先检查一下去套接字看是否在上发生了错误并且如果发生了错误就关闭套接
//字并且清除与套接字连接的 SOCKET_INFORMATION结构信息体
if (BytesTransferred == 0)
{
printf("正在关闭socket %d\n", PerHandleData->Socket);
if (closesocket(PerHandleData->Socket) == SOCKET_ERROR)
{
printf("closesocket() 发生了如下错误： %d\n", WSAGetLastError());
return 0;
}
GlobalFree(PerHandleData);
GlobalFree(PerIoData);
continue;
}
//检查如果 BytesRECV字段等于0，这就意味着一个 WSARecv调用刚刚完成了所以从完成的WSARecv()调用中
//用BytesTransferred值更新 BytesRECV字段
if (PerIoData->BytesRECV == 0)
{
PerIoData->BytesRECV = BytesTransferred;
PerIoData->BytesSEND = 0;
}
else
{
PerIoData->BytesSEND += BytesTransferred;
}
if (PerIoData->BytesRECV > PerIoData->BytesSEND)
{
//发布另外一个 WSASend()请求
//既然WSASend()不是 gauranteed去发送所有字节的请求
//继续调用 WSASend()发送直到所有收到的字节被发送
ZeroMemory(&(PerIoData->Overlapped), sizeof(OVERLAPPED));
PerIoData->DataBuf.buf = PerIoData->Buffer + PerIoData->BytesSEND;
PerIoData->DataBuf.len = PerIoData->BytesRECV - PerIoData->BytesSEND;
if (WSASend(PerHandleData->Socket, &(PerIoData->DataBuf), 1, &SendBytes, 0,
&(PerIoData->Overlapped), NULL) == SOCKET_ERROR)
{
if (WSAGetLastError() != ERROR_IO_PENDING)
{
printf("WSASend() 发生了如下错误： %d\n", WSAGetLastError());
return 0;
}
}
}
else
{
PerIoData->BytesRECV = 0;
//现在没有更多的字节发送过去用来post另外一个WSARecv()请求
Flags = 0;
ZeroMemory(&(PerIoData->Overlapped), sizeof(OVERLAPPED));
PerIoData->DataBuf.len = DATA_BUFSIZE;
PerIoData->DataBuf.buf = PerIoData->Buffer;
if (WSARecv(PerHandleData->Socket, &(PerIoData->DataBuf), 1, &RecvBytes, &Flags,
&(PerIoData->Overlapped), NULL) == SOCKET_ERROR)
{
if (WSAGetLastError() != ERROR_IO_PENDING)
{
printf("WSARecv() 发生了如下错误： %d\n", WSAGetLastError());
return 0;
}
}
}
}
}