2月7日作业-编程知识

分别通过select、多进程、多线程实现一个并发服务器

#include <myhd.h>
#define IP "192.168.250.100"
#define PORT 8888
int deal_cli_msg(int newfd,struct sockaddr_in cin)
{char buf[128] = "";while(1){bzero(buf,sizeof(buf));int res = recv(newfd,buf,sizeof(buf),0);if(res == 0){printf("客户端已下线\n");break;}else if(res < 0){perror("recv error");return -1;}strcat(buf,"->is read\n");send(newfd,buf,sizeof(buf),0);}close(newfd);return 0;
}
void handler(int signo)
{if(signo == SIGCHLD){while(waitpid(-1,NULL,WNOHANG) > 0);}
}
int main(int argc, const char *argv[])
{int sfd = socket(AF_INET,SOCK_STREAM,0);if(sfd == -1){perror("socket error");return -1;}printf("socket success,sfd = %d\n",sfd);int reuse = 1;if(setsockopt(sfd,SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse)) == -1){perror("setsocket error");return -1;}struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) == -1){perror("bind error");return -1;}printf("bind success");if(listen(sfd,128) == -1){perror("listen error");return -1;}printf("listen success");struct sockaddr_in cin;cin.sin_family = AF_INET;socklen_t socklen = sizeof(cin);pid_t pid;if(signal(SIGCHLD,handler) == SIG_ERR){perror("signal error");return -1;}while(1){int newfd = accept(sfd,(struct sockaddr*)&cin,&socklen);if(newfd == -1){perror("accept error");return -1;}printf("accept success");pid = fork();if(pid > 0){close(newfd);}else if(pid == 0){close(sfd);deal_cli_msg(newfd,cin);exit(EXIT_SUCCESS);}else{perror("fork error");return -1;}}close(sfd);return 0;
}

#include <myhd.h>
#define PORT 8888
#define IP "192.168.250.100"
struct msg_info
{int newfd;struct sockaddr_in cin;
};
void *deal_cli_msg(void *arg)
{int newfd = ((struct msg_info*)arg) -> newfd;struct sockaddr_in cin = ((struct msg_info*)arg) -> cin;char buf[128] = "";while(1){bzero(buf,sizeof(buf));int res = recv(newfd,buf,sizeof(buf),0);if(res == 0){printf("客户端已下线\n");break;}else if(res < 0){perror("recv error");return NULL;}strcat(buf,"->is read\n");send(newfd,buf,sizeof(buf),0);}close(newfd);pthread_exit(NULL);
}
int main(int argc, const char *argv[])
{int sfd = socket(AF_INET,SOCK_STREAM,0);if(sfd == -1){perror("socket error");return -1;}printf("socket success,sfd = %d\n",sfd);int reuse = 1;if(setsockopt(sfd,SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse)) == -1){perror("setsockopt error");return -1;}printf("setsockopt success\n");struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);if(bind(sfd,(struct sockaddr*)&sin,sizeof(sin)) == -1){perror("bind error");return -1;}printf("bind success\n");if(listen(sfd,128) == -1){perror("listen error");return -1;}printf("listen success\n");struct sockaddr_in cin;cin.sin_family = AF_INET;socklen_t socklen = sizeof(cin);while(1){int newfd = accept(sfd,(struct sockaddr*)&cin,&socklen);if(newfd == -1){perror("accept error");return -1;}printf("accept success\n");struct msg_info info = {newfd,cin};pthread_t tid;if(pthread_create(&tid,NULL,deal_cli_msg,&info) != 0){printf("pthread_create error\n");return -1;}if(pthread_detach(tid) != 0){printf("pthread_detach error\n");return -1;}}close(sfd);return 0;
}

#include<myhd.h>#define PORT 8888              //端口号
#define IP "192.168.250.100"       //IP地址//封装处理客户端信息函数
int deal_cli_msg(int newfd, struct sockaddr_in cin)
{//5、收发数据使用newfd完成通信char buf[128] = "";while(1){//清空字符串bzero(buf, sizeof(buf));//read(newfd, buf, sizeof(buf));        //从套接字中读取客户端发来的消息int res = recv(newfd, buf, sizeof(buf), 0);        //从套接字中读取客户端发来的消息//buf[strlen(buf)-1] = '\0';//判断收到的结果if(res == 0){printf("客户端已经下线\n");break;}else if(res < 0){perror("recv error");return -1;}printf("[%s:%d]：%s\n", inet_ntoa(cin.sin_addr), ntohs(cin.sin_port), buf);//将读取的信息，加上一些字符发送回去strcat(buf, " -> is read\n");//    write(newfd, buf, sizeof(buf));send(newfd, buf, sizeof(buf), 0); }close(newfd);             //关闭通信的套接字}int main(int argc, const char *argv[])
{//1、创建用于接受连接的套接字int sfd = socket(AF_INET, SOCK_STREAM, 0);if(sfd == -1){perror("socket error");return -1;}printf("socket success sfd = %d\n", sfd);    //4//设置端口号快速重用int reuse = 1;if(setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) == -1){perror("setsockopt error");return -1;}printf("设置端口快速重用成功 _%d_ %s_ %s_\n", __LINE__, __FILE__, __func__);//2、绑定IP地址和端口号//2.1、填充要绑定的地址信息结构体struct sockaddr_in sin;sin.sin_family     = AF_INET;         //表明是ipv4sin.sin_port     = htons(PORT);        //端口号sin.sin_addr.s_addr = inet_addr(IP);     //IP地址//2.2、绑定if(bind(sfd, (struct sockaddr*)&sin, sizeof(sin))==-1){perror("bind error");return -1;}printf("bind success _%d_ %s_ %s_\n", __LINE__, __FILE__, __func__);//3、将套接字设置成被动监听状态if(listen(sfd, 128) == -1){perror("listen error");return -1;}printf("listen success _%d_ %s_ %s_\n", __LINE__, __FILE__, __func__);//4、阻塞等待客户端连接请求，如果有新的客户端连接，则创建一个新的用于通信的套接字//4.1、定义客户端地址信息结构体struct sockaddr_in cin;             //客户端地址信息结构体cin.sin_family     = AF_INET;socklen_t socklen = sizeof(cin);          //客户端地址信息的大小定义一个用于检测文件描述符的集合fd_set readfds, tempfds;                          //在栈区定义清空容器中的内容FD_ZERO(&readfds);将要检测的文件描述符放入集合中FD_SET(sfd, &readfds);           //将sfd文件描述符放入FD_SET(0, &readfds);             //将0号文件描述符放入//定义一个容器char buf[128] = "";int res = 0;             //接收select的返回值while(1){将集合内容复制一份tempfds = readfds;使用select阻塞等待集合中的文件描述符有事件产生res = select(sfd+1, &tempfds, NULL, NULL, NULL);if(res == -1){perror("select error");return -1;}else if(res == 0){printf("time out\n");return -1;}判断sfd是否还在集合中if(FD_ISSET(sfd, &tempfds)){//4.2、阻塞接收客户端的链接请求，并且获取客户端的地址信息int newfd = accept(sfd, (struct sockaddr*)&cin, &socklen);if(newfd == -1){perror("accept error");return -1;}printf("accept success _%d_ %s_ %s_\n", __LINE__, __FILE__, __func__);deal_cli_msg(newfd,cin);}if(FD_ISSET(0, &tempfds)){//从终端获取数据fgets(buf, sizeof(buf), stdin);       //从终端获取数据buf[strlen(buf)-1]='\0';printf("触发终端输入事件:%s\n", buf);}}//6、关闭所有套接字close(sfd);               //关闭监听return 0;
}