#include
#include
#include
using namespace std;
#pragma comment(lib,"Ws2_32.lib")
const int nPort=10000;
const int buf_len=1024;
struct Connection{
SOCKET hSocket;
char Buffer[buf_len];
int nBytes;
Connection(SOCKET socket):hSocket(socket),nBytes(0)//结构体构造函数，hSocket的初始值为socket，nBytes的初始值为0；
{}
}; //注意：要加分号
typedef vector ConnectionList;
SOCKET BindListen()
{
SOCKET HSListen=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);//创建套接字
sockaddr_in sdListen;
sdListen.sin_family=AF_INET;
sdListen.sin_port=htons(nPort);
sdListen.sin_addr.s_addr=htonl(INADDR_ANY);
if(bind(HSListen,(sockaddr*)&sdListen,sizeof(sockaddr_in))==SOCKET_ERROR)
{
cout<<"绑定失败"<nByteshSocket,&fdRead);
}
//客户连接的缓冲区还有数据需要发送，就需要把其对应的套接字句柄放入到fdWrite中
if(pConn->nBytes>0)
{
FD_SET(pConn->hSocket,&fdWrite);
}
//每个连接的套接字句柄都需要放到fd_Except中，以便select 能够检测其I/O错误
FD_SET(pConn->hSocket,&fdExcept);
}
}
//检查是否有新的客户连接
int CheckAccept(const fd_set &fdRead,const fd_set &fdExcept,SOCKET sdListen,ConnectionList &conns)
{
int lastErr=0;
//首先检查是否发生错误
if(FD_ISSET(sdListen,&fdExcept))
{
int errlen=sizeof(lastErr);
getsockopt(sdListen,SOL_SOCKET,SO_ERROR,(char *)&lastErr,&errlen);
cout<<"I/O error"<=FD_SETSIZE-1)
{
return 0;
}
//调用accept来接受连接请求
sockaddr_in saRemote;
int nSize=sizeof(sockaddr_in);
SOCKET sd=accept(sdListen,(sockaddr *)&saRemote,&nSize);
lastErr=WSAGetLastError();
//为了程序的健壮性，检查WSAEWOULDBLOCK错误
if(sd==INVALID_SOCKET&&lastErr!=WSAEWOULDBLOCK)
{
cout<<"接收错误"<0)
{
//使用阻塞I/O模型把剩余数据发送出去
u_long nNoBlock=0;
if(ioctlsocket(sd,FIONBIO,&nNoBlock)==SOCKET_ERROR)
{
cout<<"ioctlsocket error"<0)
{
nSent+=nTemp;
}
else if(nTemp==SOCKET_ERROR)
{cout<<"发送失败"<buffer+pConn->nBytes表示缓冲区Buffer可用空间的开始位置
//buf_len-pConn->nBytes表示缓冲区Buffer可用空间的大小
int nRet=recv(pConn->hSocket ,pConn->Buffer+pConn->nBytes,buf_len-pConn->nBytes,0);
if(nRet>0)
{
pConn->nBytes+=nRet;
return true;
}
//对方关闭了连接，调用被动安全关闭连接PassiveShutdown函数
else if(nRet==0)
{
cout<<"对方关闭连接"<hSocket,pConn->Buffer,pConn->nBytes);
return false;
}
//发生了错误。为了程序的健壮性，检查WSAEWOULDBLOCK错误
else
{
int lastErr=WSAGetLastError();
if(lastErr==WSAEWOULDBLOCK)
{
return true;
}
cout<<"接收失败"<hSocket,pConn->Buffer,pConn->nBytes,0);
if(nSent>0)
{
pConn->nBytes-=nSent;
//Buffer中还有数据尚未发送出去
if(pConn->nBytes>0)
{
//把尚未发送的数据从Buffer的尾部移动到Buffer头部
memmove(pConn->Buffer,pConn->Buffer+nSent,pConn->nBytes);
}
return true;
}
//对方关闭了连接，调用了被动安全关闭连接PassiveShutdown函数
else if(nSent==0)
{
cout<<"对方关闭连接"<hSocket,pConn->Buffer,pConn->nBytes);
return false;
}
//发生了错误，为了程序的健壮性，检查WSAEWOULDBLOCK错误
else
{
int lastErr=WSAGetLastError();
if(lastErr==WSAEWOULDBLOCK)
{
return true;
}
cout<<"发送失败"<hSocket,&fdExcept))
{
bOk=false;
int lastErr;
int errlen=sizeof(lastErr);
getsockopt(pConn->hSocket,SOL_SOCKET,SO_ERROR,(char*)&lastErr,&errlen);
cout<<"I/O error"<hSocket,&fdRead))
{
bOk=TryRead(pConn);
}
}
//发生了错误，关闭套接字并把其对应的Connection对象从conns中移除
if(bOk==false)
{
closesocket(pConn->hSocket);
delete pConn;
it=conns.erase(it);
}
else
{
++it;
}
}
}
//select就绪通告I/O模型服务器的主体函数
void DoWork()
{
//获取监听套接字
SOCKET sdListen=BindListen();
if(sdListen==INVALID_SOCKET)
{}
//定义conns，用于保存当前所有客户连接
ConnectionList conns;
//把监听套接字设为非阻塞模式
u_long nNoBlock=1;
if(ioctlsocket(sdListen,FIONBIO,&nNoBlock)==SOCKET_ERROR)
{
cout<<"ioctlsocket 错误"<hSocket);
delete *it;
}
if(sdListen!=INVALID_SOCKET)
closesocket(sdListen);
}
int main()
{
WSAData wsaData;
int nCode;
if((nCode=WSAStartup(MAKEWORD(2,2),&wsaData))!=0)
{
cout<<"初始化失败"<
