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2023.07.29 驱动开发DAY6

news 2025/7/10 0:08:53

通过epoll实现一个并发服务器

服务器

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/epoll.h>#define ERR_MSG(msg)               \
do {                               \printf("LINE: %d\n", __LINE__);\perror(msg);                   \
} while(0)#define PORT 6666
#define IP "127.0.0.1"int main(int argc,const char * argv[])
{//创建流式套接字int sfd = socket(AF_INET, SOCK_STREAM, 0);if(sfd < 0){ERR_MSG("socket");return -1;}printf("socket create success\n");//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("setsockopt success\n");//填充地址信息结构体struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);//将IP地址和端口号绑定到指定的套接字文件描述符上if(bind(sfd, (struct sockaddr*)&sin, sizeof(sin)) < 0){ERR_MSG("bind");return -1;}printf("bind success\n");//将通讯套接字设置为被动监听状态if(listen(sfd, 128) < 0){ERR_MSG("listen");return -1;}printf("listen success\n");// 创建epoll句柄int epfd = epoll_create(1);if(epfd < 0){printf("epoll_create filed\n");return -1;}// 添加准备就绪事件进入epoll;struct epoll_event event;struct epoll_event events[10]; //存放就绪事件描述符的数组event.events = EPOLLIN; // 读事件event.data.fd = sfd;if(epoll_ctl(epfd, EPOLL_CTL_ADD, sfd, &event) < 0){printf("epoll_ctl add filed\n");}//监听事件是否发生struct sockaddr_in cin;        //存储客户端信息socklen_t len = sizeof(cin);struct sockaddr_in savecin[1024];int ret, res;char buf[128] = {};while(1){//如果成功，ret接收返回的事件个数，把就绪的事件放在events数组中ret = epoll_wait(epfd, events, 10, -1);if(ret < 0){printf("epoll_wait filed\n");return -1;}//循环遍历数组，做事件处理for(int i=0; i<ret; i++){if(events[i].events & EPOLLIN){if(events[i].data.fd == sfd){//触发客户端连接事件int newfd = accept(sfd, (struct sockaddr*)&cin, &len);if(newfd < 0){ERR_MSG("accpet");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;//添加新连接客户端进入epoll;event.events = EPOLLIN; // 读事件event.data.fd = newfd;if(epoll_ctl(epfd, EPOLL_CTL_ADD, newfd, &event) < 0){printf("epoll_ctl add filed\n");return -1;}}else{//触发客户端交互事件                   //接收数据int cfd = events[i].data.fd;bzero(buf, sizeof(buf));res = recv(cfd, buf, sizeof(buf), 0);if(res < 0){ERR_MSG("recv");return -1;}else if(res == 0){printf("[%s:%d] 客户端下线 cfd=%d\n", inet_ntoa(savecin[cfd].sin_addr), ntohs(savecin[cfd].sin_port), cfd);close(cfd); // 关闭文件描述符//添加断开连接的客户端从epoll中删除;if(epoll_ctl(epfd, EPOLL_CTL_DEL, cfd, NULL) < 0){printf("epoll_ctl del filed\n");return -1;}continue;}printf("[%s:%d] cfd=%d: %s\n", inet_ntoa(savecin[cfd].sin_addr), ntohs(savecin[cfd].sin_port), cfd, buf);// 发送数据strcat(buf, "*_*");if(send(cfd, buf, sizeof(buf), 0) < 0){ERR_MSG("send");return -1;}}}}}return 0;
}

客户端

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>#define ERR_MSG(msg)               \
do {                               \printf("LINE: %d\n", __LINE__);\perror(msg);                   \
} while(0)#define PORT 6666
#define IP "127.0.0.1"int main(int argc,const char * argv[])
{//创建流式套接字int cfd = socket(AF_INET, SOCK_STREAM, 0);if(cfd < 0){ERR_MSG("socket");return -1;}printf("socket create success\n");//填充地址信息结构体struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(PORT);sin.sin_addr.s_addr = inet_addr(IP);//连接到服务器if(connect(cfd, (struct sockaddr*)&sin, sizeof(sin)) < 0){ERR_MSG("connect");return -1;}printf("connect server success\n");char buf[128] = "";ssize_t res = 0;while(1){//发送数据bzero(buf, sizeof(buf));printf("请输入>>> ");fgets(buf, sizeof(buf), stdin);buf[strlen(buf)-1] = 0;if(send(cfd, buf, sizeof(buf), 0) < 0){ERR_MSG("send");return -1;}printf("发送成功\n");//接收数据bzero(buf, sizeof(buf));res = recv(cfd, buf, sizeof(buf), 0);if(res < 0){ERR_MSG("recv");return -1;}else if(0 == res){printf("[%s:%d] 服务器下线\n", inet_ntoa(sin.sin_addr), ntohs(sin.sin_port));break;}printf("[%s:%d]: %s\n", inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), buf); }close(cfd);return 0;
}

运行结果