Programación de red-día 5

Escriba el servidor de acuerdo con el diagrama de flujo del servidor TCP seleccionado

#include <myhead.h>	

#define ERR_MSG(msg) do{\
	fprintf(stderr, "__%d__\n", __LINE__);\
	perror(msg);\
}while(0)

#define PORT 8888
#define IP "192.168.114.96"

int main(int argc, const char *argv[])
{
	//创建套接字
	int sfd = socket(AF_INET, SOCK_STREAM, 0);
	if(sfd < 0)
	{
		ERR_MSG("socket");
		return -1;
	}
	printf("socket create success sfd=%d\n", sfd);

	//允许端口快速复用
	int reuse = 1;
	if(setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) < 0)
	{
		ERR_MSG("setsockopt");
		return -1;
	}
	printf("允许端口快速复用成功\n");

	//通用地址信息结构体
	struct sockaddr_in sin;
	sin.sin_family 			= AF_INET;
	sin.sin_port 			= htons(PORT);
	sin.sin_addr.s_addr 	= inet_addr(IP);

	//绑定
	if(bind(sfd, (struct sockaddr *)&sin, sizeof(sin)) < 0)
	{
		ERR_MSG("bind");
		return -1;
	}
	printf("bind success\n");

	//转换成监听套接字
	if(listen(sfd, 128) < 0)
	{
		ERR_MSG("listen");
		return -1;
	}
	printf("listen success\n");

	//定义读集合和备份
	fd_set readfds, tempfds;
	//清空集合
	FD_ZERO(&readfds);

	//将0号和sfd添加到读集合中
	FD_SET(0, &readfds);
	FD_SET(sfd, &readfds);

	int res1 = -1;
	ssize_t res2 = -1;

	char buf[128] = "";
	struct sockaddr_in cin;
	socklen_t addrlen = sizeof(cin);
	struct sockaddr_in saveCin[1024];  //下标对应文件描述符

	//定义最大的文件描述符
	int maxfd = sfd;
	int newfd = -1;

	while(1)
	{
		//将readfds拷贝一份给tempfds
		tempfds = readfds;

		//执行IO多路复用函数
		res1 = (select(maxfd+1, &tempfds, NULL, NULL, NULL));
		if(res1 < 0)
		{
			ERR_MSG("select");
			return -1;
		}else if(0 == res1)
		{
			printf("time out\n"); //超时
			break;
		}

		printf("__%d__\n", __LINE__);

		for(int i=0; i<maxfd; i++)
		{
			if(FD_ISSET(i, &tempfds) == 0)
				continue;
			//说明i代表的文件描述符在集合中
			if(0 == i)
			{
				//触发键盘输入事件
				printf("触发键盘输入事件\n");		
				//清空字符串
				bzero(buf, sizeof(buf));
				fgets(buf, sizeof(buf), stdin);
				buf[strlen(buf)-1] = 0;

				printf("%s\n", buf);

			}else if(sfd == i)
			{
				//触发客户端连接事件
				printf("触发客户端连接事件\n");
				newfd = accept(sfd, (struct sockaddr *)&cin, &addrlen);
				if(newfd < 0)
				{
					ERR_MSG("accept");
					return -1;
				}
				printf("[%s:%d] 客户端连接成功 newfd=%d\n", \
						inet_ntoa(cin.sin_addr), ntohs(cin.sin_port), newfd);

				saveCin[newfd] = cin;
				FD_SET(newfd, &readfds);
				maxfd = maxfd>newfd ? maxfd:newfd;
			}else
			{
				//触发客户端交互事件
				printf("触发客户端交互事件\n");
				
				//清空字符串
				bzero(buf, sizeof(buf));
				//接收数据
				res2 = recv(i, buf, sizeof(buf), 0);
				if(res2 < 0)
				{
					ERR_MSG("recv");
					return -1;
				}
				
				if(0 == res2)
				{
				printf("[%s:%d] 客户端下线 newfd=%d\n", \
						inet_ntoa(saveCin[i].sin_addr), ntohs(saveCin[i].sin_port), i);
			
					//关闭文件描述符
					close(i);
					//将文件描述符从集合中剔除
					FD_CLR(i, &readfds);

					while(FD_ISSET(maxfd, &readfds)==0 && maxfd-->=0);
				}
				printf("[%s:%d] newfd=%d : %s\n", \
						inet_ntoa(saveCin[i].sin_addr), ntohs(saveCin[i].sin_port), i, buf);
				
				//发送数据
				strcat(buf, "O.o");
				if(send(i, buf, sizeof(buf), 0) < 0)
				{
					ERR_MSG("send");
					return -1;
				}
				printf("send success\n");

			}

		}

	}

	//关闭文件描述符
	if(close(sfd) < 0)
	{
		ERR_MSG("close");
		return -1;
	}
	printf("close success\n");

	return 0;
}

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