Chat实验

#include <stdio.h>
#include <string.h>
#include <process.h>
#include <winsock2.h>
#define BUFLEN 2000
#define WSVERS MAKEWORD(2, 0)
#pragma comment(lib, "ws2_32.lib")
int finish = 0;
unsigned __stdcall recvMessage(SOCKET *p)
{
	for (char buf[BUFLEN];;)
	{
		int cc = recv(*p, buf, BUFLEN, 0); // BUFLEN为缓冲区buf的长度，返回值：接收的字符数(>0)、对方已关闭(=0) 或连接出错(<0)
		if (finish)
			return 0;
		if (cc > 0)
		{
			buf[cc] = '\0';	//  ensure null-termination
			printf("%s", buf); // 显示所接收的字符串
		}
		else if (cc == SOCKET_ERROR)
			printf("Recv Error:\n%d\n", GetLastError());
		else if (cc == 0)
			printf("Recv connect closed.\n");
	}
}
int main()
{
	char buf[BUFLEN];
	WSADATA wsadata;
	WSAStartup(WSVERS, &wsadata);
	struct sockaddr_in sin; // an Internet endpoint address
	memset(&sin, 0, sizeof(sin));
	sin.sin_family = AF_INET; // 因特网地址簇
	printf("Input the IP address:\n");
	gets(buf);
	sin.sin_addr.s_addr = inet_addr(buf); // 服务器IP地址(32位)
	printf("Input the IP port:\n");
	gets(buf);
	sin.sin_port = htons(atoi(buf));						 // 服务器端口号(16位)
	SOCKET sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP); // socket descriptor
	int ret = connect(sock, &sin, sizeof(sin));				 // 连接到服务器.无错时，返回0；否则，返回SOCKET_ERROR ，可以调用函数WSAGetLastError取得错误代码
	HANDLE h = _beginthreadex(NULL, 0, &recvMessage, &sock, 0, NULL);
	for (;;)
	{
		gets(buf);
		if (!strcmp(buf, "exit"))
			break;
		int cc = send(sock, buf, strlen(buf), 0); //把缓冲区buf的数据发送出去，len为要发送的字节数，返回值：(>0) 实际发送的字节数(≤len), (=0) 对方正常关闭，（=SOCKET_ERROR) 出错，用函数WSAGetLastError取错误码。
		if (cc == SOCKET_ERROR)
			printf("Send Error:\n%d\n", GetLastError());
		else if (cc == 0)
			printf("Send connect closed.\n");
	}
	finish = 1;
	CloseHandle(h);
	closesocket(sock); // 关闭套接字
	WSACleanup();	  //  卸载winsock library
	system("pause");
}

#include <stdio.h>
#include <time.h>
#include <process.h>
#include <winsock2.h>
#define BUFLEN 2000
#define WSVERS MAKEWORD(2, 0)
#pragma comment(lib, "ws2_32.lib") //使用winsock 2.2 library
SOCKET ssock[BUFLEN];			   //master & *p sockets
struct sockaddr_in ssin[BUFLEN];
int sbadd[BUFLEN], ssock_size = 0;
unsigned __stdcall server(int *p)
{
	for (char msg[BUFLEN] = "Enter!", pts[BUFLEN];;)
	{
		time_t now = time(NULL);
		sprintf(pts,
				"ip: %d.%d.%d.%d port: %u\n"
				"time: %s"
				"message: %s\n"
				"\n>>",
				ssin[*p].sin_addr.S_un.S_un_b.s_b1,
				ssin[*p].sin_addr.S_un.S_un_b.s_b2,
				ssin[*p].sin_addr.S_un.S_un_b.s_b3,
				ssin[*p].sin_addr.S_un.S_un_b.s_b4,
				ssin[*p].sin_port,
				ctime(&now),
				msg);
		printf(pts);
		for (int i = 0; i < ssock_size; ++i)
			send(ssock[i], pts, strlen(pts), 0);
		if (!strcmp(msg, "Leave!"))
			return closesocket(ssock[*p]), 0; //关闭连接套接字
		int cc = recv(ssock[*p], msg, BUFLEN, 0);
		if (cc > 0)
			msg[cc] = 0;
		else
			sprintf(msg, "Leave!");
	}
}
int main()
{
	WSADATA wsadata;
	WSAStartup(WSVERS, &wsadata);							  //加载winsock library，WSVERS为请求版本，wsadata返回系统实际支持的最高版本
	struct sockaddr_in msin;								  //an Internet endpoint addresss
	memset(&msin, 0, sizeof(msin));							  //从&sin开始的长度为sizeof(sin)的内存清0 , sin为一个地址结构
	msin.sin_family = AF_INET;								  //因特网地址簇(INET-Internet)
	msin.sin_addr.s_addr = INADDR_ANY;						  //监听所有(接口的)IP地址(32位)，0.0.0.0
	msin.sin_port = htons(atoi("50500"));					  //监听的端口号(16位) 。atoi--把ascii转化为int，htons—主机序到网络序
	SOCKET msock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP); //创建套接字。参数：因特网协议簇(family)，字节流，TCP协议号。 返回：要监听套接字的描述符或INVALID_SOCKET
	bind(msock, (struct sockaddr *)&msin, sizeof(msin));	  //通过msin把要监听的IP地址和端口号绑定到套接字上
	listen(msock, 5);										  //建立长度为5的连接请求队列，并开始监听是否有连接请求到来，来了则放入队列
	printf("Server Start to listen.\n");
	while (!_kbhit()) //检测是否有按键 (什么时候执行？)
	{
		int alen = sizeof(struct sockaddr);												//from-address length
		ssock[ssock_size] = accept(msock, (struct sockaddr *)&ssin[ssock_size], &alen); //accept：如果有新的连接请求，返回连接套接字，否则，被阻塞，ssin包含客户端IP地址和端口号
		sbadd[ssock_size] = ssock_size;
		_beginthreadex(NULL, 0, &server, &sbadd[ssock_size++], 0, NULL);
	}
	closesocket(msock);
	WSACleanup();
	system("pause");
}