TCP Socket编程（非阻塞模式）（C++）

代码来源：《Windows网络编程》（罗莉琴，詹祖桥 主编）（如造成任何不便，请联系我删除）

服务器：

// TcpServer.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include 
#include 

#pragma comment(lib,"ws2_32.lib")

#define BUF_SIZE 64

int _tmain(int argc, _TCHAR* argv[])
{
	WSADATA wsd;
	SOCKET sServer;
	SOCKET sClient;
	int retVal;
	char buf[BUF_SIZE];

	//初始化Socket
	if (WSAStartup(MAKEWORD(2, 2), &wsd) != 0)
	{
		printf("WSAStartup failed!\n");
		return -1;
	}
	//创建用于监听的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;
	}
	//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Socket Server到本地地址
	retVal = bind(sServer,(const struct sockaddr*)&addrServ,sizeof(sockaddr_in));
	if (retVal == SOCKET_ERROR)
	{
		printf("bind failed!\n");
		closesocket(sServer);
		WSACleanup();
		return -1;
	}
	//监听
	retVal = listen(sServer,1);
	if (retVal == SOCKET_ERROR)
	{
		printf("listen failed!\n");
		closesocket(sServer);
		WSACleanup();
		return -1;
	}
	//接受客户请求
	printf("TCP Server start...\n");
	sockaddr_in addrClient;
	int addrClientlen = sizeof(addrClient);
	//循环等待
	while (true)
	{
		sClient = accept(sServer,(sockaddr FAR*)&addrClient,&addrClientlen);
		if (INVALID_SOCKET == sClient)
		{
			int err = WSAGetLastError();
			if (err == WSAEWOULDBLOCK)
			{
				Sleep(100);
				continue;
			}
			else
			{
				printf("accept failed!\n");
				closesocket(sServer);
				WSACleanup();
				return -1;
			}		
		}
		break;

	}
	//循环接受客户端的数据，直到客户端发送quit命令后退出
	while (true)
	{
		ZeroMemory(buf,BUF_SIZE);
		retVal = recv(sClient,buf,BUFSIZ,0);
		if (SOCKET_ERROR == retVal)
		{
			int err = WSAGetLastError();
			if (err == WSAEWOULDBLOCK)
			{
				Sleep(100);
				continue;
			}
			else if (err == WSAETIMEDOUT || err == WSAENETDOWN)
			{
				printf("recv failed!\n");
				closesocket(sServer);
				closesocket(sClient);
				WSACleanup();
				return -1;
			}
		}
		//获取系统时间
		SYSTEMTIME st;
		GetLocalTime(&st);
		char sDateTime[30];
		sprintf_s(sDateTime, "%4d-%2d-%2d %2d:%2d:%2d", st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond);
		//打印输出信息
		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") == 0)
		{
			retVal = send(sClient,"quit",strlen("quit"),0);
			break;
		}
		else
		{
			char msg[BUF_SIZE];
			sprintf_s(msg,"Message received - %s",buf);
			while (true)
			{
				retVal = send(sClient,msg,strlen(msg),0);
				if (SOCKET_ERROR == retVal)
				{
					int err = WSAGetLastError();
					if (err == WSAEWOULDBLOCK)
					{
						Sleep(100);
						continue;
					}
					else
					{
						printf("send failed!\n");
						closesocket(sServer);
						closesocket(sClient);
						WSACleanup();
						return -1;
					}
					
				}
				break;
			}
		}
	}
	
	//释放Socket
	closesocket(sServer);
	closesocket(sClient);
	WSACleanup();

	system("pause");
	return 0;
}

客户端：

// TcpClient.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include 
#include 
#include 

#pragma comment(lib,"ws2_32.lib")
#define BUF_SIZE 64


int _tmain(int argc, _TCHAR* argv[])
{
	WSADATA wsd;
	SOCKET sHost;
	SOCKADDR_IN servAddr;
	char buf[BUF_SIZE];
	int retVal;
	//初始化Socket
	if (WSAStartup(MAKEWORD(2, 2), &wsd) != 0)
	{
		printf("WSAStartup failed!\n");
		return -1;
	}
	//创建Socket
	sHost = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
	if (INVALID_SOCKET == sHost)
	{
		printf("socket failed!\n");
		WSACleanup();
		return -1;
	}
	//设置Socket为非阻塞模式
	int iMode = 1;
	retVal = ioctlsocket(sHost, FIONBIO, (u_long FAR*)&iMode);
	if (retVal == SOCKET_ERROR)
	{
		printf("ioctlsocket failed!\n");
		WSACleanup();
		return -1;
	}
	//设置服务器Socket地址
	servAddr.sin_family = AF_INET;
	servAddr.sin_port = htons(9990);
	servAddr.sin_addr.S_un.S_addr = inet_addr("ip地址");//htonl(INADDR_ANY);
	
	int sServerAddlen = sizeof(servAddr);

	//连接到服务器
	while (true)
	{
		retVal = connect(sHost,(LPSOCKADDR)&servAddr,sizeof(servAddr));
		if (SOCKET_ERROR == retVal)
		{
			int err = WSAGetLastError();
			if (err == WSAEWOULDBLOCK || err == WSAEINVAL)
			{
				Sleep(500);
				continue;
			}
			else if (err == WSAEISCONN)
			{
				break;
			}
			else
			{
				printf("connection failed!\n");
				closesocket(sHost);
				WSACleanup();
				return -1;
			}
		}
	}

	//收发数据
	while (true)
	{
		printf("Please input a string to send:");
		std::string str;
		std::getline(std::cin,str);
		ZeroMemory(buf,BUF_SIZE);
		strcpy_s(buf,str.c_str());
		while (true)
		{
			retVal = send(sHost,buf,strlen(buf),0);
			if (SOCKET_ERROR == retVal)
			{
				int err = WSAGetLastError();
				if (err == WSAEWOULDBLOCK)
				{
					Sleep(500);
					continue;
				}
				else
				{
					printf("send failed!\n");
					closesocket(sHost);
					WSACleanup();
					return -1;
				}
			}
			break;

		}
		
		while (true)
		{
			ZeroMemory(buf,BUF_SIZE);
			retVal = recv(sHost,buf,sizeof(buf)+1,0);
			if (SOCKET_ERROR == retVal)
			{
				int err = WSAGetLastError();
				if (err == WSAEWOULDBLOCK)
				{
					Sleep(100);
					printf("waiting back msg!\n");
					continue;
				}
				else if (err == WSAETIMEDOUT || err == WSAENETDOWN)
				{
					printf("recv failed!\n");
					closesocket(sHost);
					WSACleanup();
					return -1;
				}
				break;
			}
			break;
			
		}
		printf("Recv From Server:%s\n",buf);
		if (strcmp(buf, "quit") == 0)
		{
			printf("quit!\n");
			break;
		}
	}

	closesocket(sHost);
	WSACleanup();
	system("pause");

	return 0;
}