linux ace epoll

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/epoll.h>

#define MAX_EVENTS 10
#define PORT 8080

int main() {
    int listen_fd, conn_fd, epoll_fd, nfds, n;
    struct epoll_event ev, events[MAX_EVENTS];
    struct sockaddr_in server_addr;

    listen_fd = socket(AF_INET, SOCK_STREAM, 0);
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(PORT);
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    bind(listen_fd, (struct sockaddr*)&server_addr, sizeof(server_addr));
    listen(listen_fd, SOMAXCONN);

    epoll_fd = epoll_create1(0);
    ev.events = EPOLLIN;
    ev.data.fd = listen_fd;
    epoll_ctl(epoll_fd, EPOLL_CTL_ADD, listen_fd, &ev);

    while (1) {
        nfds = epoll_wait(epoll_fd, events, MAX_EVENTS, -1);
        for (n = 0; n < nfds; ++n) {
            if (events[n].data.fd == listen_fd) {
                conn_fd = accept(listen_fd, (struct sockaddr*)NULL, NULL);
                ev.events = EPOLLIN | EPOLLET;
                ev.data.fd = conn_fd;
                epoll_ctl(epoll_fd, EPOLL_CTL_ADD, conn_fd, &ev);
            } else {
                // 处理客户端数据
                char buf[1024];
                int len = read(events[n].data.fd, buf, sizeof(buf));
                if (len <= 0) {
                    close(events[n].data.fd);
                    epoll_ctl(epoll_fd, EPOLL_CTL_DEL, events[n].data.fd, &ev);
                } else {
                    write(events[n].data.fd, buf, len); // 回显数据
                }
            }
        }
    }

    close(listen_fd);
    close(epoll_fd);
    return 0;
}

void close_fd(int fd) {
    if (fd >= 0) {
        close(fd);
    }
}

// 在处理事件的代码中
int conn_fd = accept(listen_fd, (struct sockaddr*)NULL, NULL);
// 使用智能指针或其他RAII技术管理conn_fd的生命周期
std::unique_ptr<int, decltype(&close_fd)> conn_ptr(&conn_fd, close_fd);