linux 环境下用 c 语言实现 reactor 网络模型的代码案例

#include <stdio.h>#include <stdlib.h>#include <unistd.h>#include <string.h>#include <sys/socket.h>#include <netinet/in.h>#include <arpa/inet.h>#include <sys/epoll.h>
#define PORT 8888 // 定义服务器端口号#define MAX_EVENTS 10#define BUFFER_SIZE 1024
int main() {    struct epoll_event event, events[MAX_EVENTS];    int listen_fd, new_fd, epoll_fd, num_events, i;    struct sockaddr_in server_addr, client_addr;    socklen_t sin_size = sizeof(client_addr);    char buffer[BUFFER_SIZE];
    // 创建服务器套接字    if ((listen_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {        perror("socket failed");        exit(EXIT_FAILURE);    }        // 设置服务器地址和端口号并绑定    server_addr.sin_family = AF_INET;    server_addr.sin_port = htons(PORT);    server_addr.sin_addr.s_addr = INADDR_ANY;    memset(server_addr.sin_zero, '\0', sizeof(server_addr.sin_zero));        if (bind(listen_fd, (struct sockaddr *)&server_addr, sizeof(server_addr)) == -1) {        perror("bind failed");        exit(EXIT_FAILURE);    }        // 监听客户端连接    if (listen(listen_fd, 10) == -1) {        perror("listen failed");        exit(EXIT_FAILURE);    }
    // 创建 epoll 实例并将服务器 socket 注册到 epoll 事件中    if ((epoll_fd = epoll_create(MAX_EVENTS)) == -1) {        perror("epoll_create failed");        exit(EXIT_FAILURE);    }        event.events = EPOLLIN;    event.data.fd = listen_fd;        if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, listen_fd, &event) == -1) {        perror("epoll_ctl failed");        exit(EXIT_FAILURE);    }        // 循环接收客户端连接并读写数据    while (1) {        num_events = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);                for (i = 0; i < num_events; i++) {            if (events[i].data.fd == listen_fd) { // 有新的客户端连接                new_fd = accept(listen_fd, (struct sockaddr *)&client_addr, &sin_size);                printf("New client connected: %s\n", inet_ntoa(client_addr.sin_addr));                                event.events = EPOLLIN;                event.data.fd = new_fd;                                if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, new_fd, &event) == -1) {                    perror("epoll_ctl failed");                    exit(EXIT_FAILURE);                }            } else { // 有客户端发送消息                if ((num_events = read(events[i].data.fd, buffer, BUFFER_SIZE)) <= 0) {                    close(events[i].data.fd);                                        if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, events[i].data.fd, &event) == -1) {                        perror("epoll_ctl failed");                        exit(EXIT_FAILURE);                    }                                        printf("Client disconnected.\n");                } else { // 处理客户端的请求                    buffer[num_events] = '\0';                    printf("Received message: %s\n", buffer);                                        if (send(events[i].data.fd, buffer, strlen(buffer), 0) == -1) {                        perror("send failed");                        exit(EXIT_FAILURE);                    }                }            }        }    }
    return 0;}