C++非阻塞模式Socket编程

iocServer.cpp：

#include<WINSOCK2.H>

#include<iostream>

using namespace std;

#include<stdlib.h>

#define BUF_SIZE 64

#pragma comment(lib,"WS2_32.lib")

int main()

{

WSADATA wsd;

SOCKET sServer;

SOCKET sClient;

int retVal;//调用Socket函数的返回值

char buf[BUF_SIZE];

//初始化Socket环境

if(WSAStartup(MAKEWORD(2,2),&wsd)!=0)

{

printf("WSAStartup failed!\n");

return 1;

}

//创建监听的Socket

sServer=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

if(INVALID_SOCKET==sServer)

{

printf("socket failed!\n");

WSACleanup();

return -1;

}

//设置服务器Socket地址

SOCKADDR_IN addrServ;

addrServ.sin_family=AF_INET;

addrServ.sin_port=htons(9990);

addrServ.sin_addr.S_un.S_addr=htonl(INADDR_ANY);

//绑定Sockets Server

retVal=bind(sServer,(const struct sockaddr*)&addrServ,sizeof(SOCKADDR_IN));

if(SOCKET_ERROR==retVal)

{

printf("bind failed!\n");

closesocket(sServer);

WSACleanup();

return -1;

}

//在Sockets Server上进行监听

retVal=listen(sServer,1);

if(SOCKET_ERROR==retVal)

{

printf("listen failed!\n");

closesocket(sServer);

WSACleanup();

return -1;

}

//设置Socket为非阻塞模式

int iMode = 1;

retVal = ioctlsocket(sServer,FIONBIO,(u_long FAR*) &iMode);

if(retVal == SOCKET_ERROR)

{

printf("ioctlsocket failed!\n");

WSACleanup();

return -1;

}

//接受来自客户端的请求

printf("TCPServer start...\n");

sockaddr_in addrClient;

int addrClientlen=sizeof(addrClient);

while(true)

{

sClient=accept(sServer,(sockaddr FAR*)&addrClient,&addrClientlen);

if(INVALID_SOCKET == sClient)

{

int err = WSAGetLastError();

if(err == WSAEWOULDBLOCK)

{

Sleep(5);

continue;

}

else

{

printf("accept failed!\n");

closesocket(sServer);

WSACleanup();

return -1;

}

}

break;

}

while(true)

{

ZeroMemory(buf,BUF_SIZE);

retVal = recv(sClient,buf,BUF_SIZE,0);

if(SOCKET_ERROR == retVal)

{

int err = WSAGetLastError();

if(err == WSAEWOULDBLOCK)

{

Sleep(5);

continue;

}

else if(err == WSAETIMEDOUT || err == WSAENETDOWN)

{

printf("recv failed!\n");

closesocket(sServer);

closesocket(sClient);

WSACleanup();

return -1;

}

}

SYSTEMTIME st;

GetLocalTime(&st);

char sDateTime[30];

sprintf(sDateTime,"%4d-%2d-%2d-%2d:%2d:%2d:%2d",st.wYear,st.wMonth,st.wDay,st.wHour,st.wMinute,st.wSecond);

//打印输出的信息

printf("%s,Recv From Client [%s:%d]:%s\n",sDateTime,inet_ntoa(addrClient.sin_addr),addrClient.sin_port,buf);

//如果客户端发送quit字符串，则服务器退出

if(strcmp(buf,"quit")==1)//////////////////////////////////////////

{

retVal=send(sClient,"quit",strlen("quit"),0);

break;

}

//否则向客户端发送回显字符串

else

{

char msg[BUF_SIZE];

sprintf(msg,"Message received - %s\n",buf);

while(true)

{

retVal = send(sClient,msg,strlen(msg),0);

if(SOCKET_ERROR == retVal)

{

int err = WSAGetLastError();

if(err == WSAEWOULDBLOCK)

{

Sleep(5);

continue;

}

else

{

printf("send failed!\n");

closesocket(sServer);

closesocket(sClient);

WSACleanup();

return -1;

}

}

}

break;

}

}

}

iocClient.cpp：

#include<WINSOCK2.H>

#include<iostream>

#include<string>

using namespace std;

#include<stdlib.h>

#define BUF_SIZE 64

#pragma comment(lib,"WS2_32.lib")

int main()

{

WSADATA wsd;

SOCKET sHost;

SOCKADDR_IN servAddr;//服务器地址

int retVal;//调用Socket函数的返回值

char buf[BUF_SIZE];

int iMode=1;

//初始化Socket环境

if(WSAStartup(MAKEWORD(2,2),&wsd)!=0)

{

printf("WSAStartup failed!\n");

return -1;

}

sHost=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

//设置服务器Socket地址

servAddr.sin_family=AF_INET;

servAddr.sin_addr.S_un.S_addr=inet_addr("127.0.0.1");

//在实际应用中，建议将服务器的IP地址和端口号保存在配置文件中

servAddr.sin_port=htons(9990);

//计算地址的长度

int sServerAddlen=sizeof(servAddr);

//调用ioctlsocket（）将其设置为非阻塞模式

retVal=ioctlsocket(sHost,FIONBIO,(u_long FAR*)&iMode);

if(retVal==SOCKET_ERROR)

{

printf("ioctlsocket failed!");

WSACleanup();

return -1;

}

//循环等待

while(true)

{

//连接到服务器

retVal=connect(sHost,(LPSOCKADDR)&servAddr,sizeof(servAddr));

if(SOCKET_ERROR==retVal)

{

int err=WSAGetLastError();

//无法立即完成非阻塞Socket上的操作

if(err==WSAEWOULDBLOCK||err==WSAEINVAL)

{

Sleep(5);

continue;

}

else if(err==WSAEISCONN)//已建立连接

{

break;

}

else

{

printf("connection failed!\n");

closesocket(sHost);

WSACleanup();

return -1;

}

}

}

while(true)

{

//向服务器发送字符串，并显示反馈信息

printf("input a string to send:\n");

std::string str;

//接收输入的数据

std::getline(std::cin,str);

//将用户输入的数据复制到buf中

ZeroMemory(buf,BUF_SIZE);

strcpy(buf,str.c_str());

while(true)

{

retVal=send(sHost,buf,strlen(buf),0);

if(SOCKET_ERROR==retVal)

{

int err=WSAGetLastError();

if(err==WSAEWOULDBLOCK)

{

//无法立即完成非阻塞Socket上的操作

Sleep(5);

continue;

}

else

{

printf("send failed!\n");

closesocket(sHost);

WSACleanup();

return -1;

}

}

break;

}

while(true)

{

ZeroMemory(buf,BUF_SIZE);//清空接收数据的缓冲区

retVal=recv(sHost,buf,sizeof(buf)+1,0);

if(SOCKET_ERROR==retVal)

{

int err=WSAGetLastError();

//无法立即完成非阻塞Socket上的操作

if(err==WSAEWOULDBLOCK)

{

Sleep(5000);

printf("waiting back msg!\n");

continue;

}

else if(err==WSAETIMEDOUT||err==WSAENETDOWN)//已建立连接

{

printf("recv failed!");

closesocket(sHost);

WSACleanup();

return -1;

}

break;

}

break;

}

ZeroMemory(buf,BUF_SIZE);

retVal=recv(sHost,buf,sizeof(buf)+1,0);

printf("Recv from Server:%s\n",buf);

//如果接收到quit，则退出

if(strcmp(buf,"quit")==0)

{

printf("quit!\n");

break;

}

}

return 0;

}