epollrdhup

c

#include <stdio.h>
#include <sys/epoll.h>  
#include <sys/socket.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/types.h>          /* See NOTES */
#include <netinet/in.h>
#include <arpa/inet.h>


#define LISTEN_HOST "127.0.0.1"
#define LISTEN_PORT 13105


static void nonblocking(int fd)
{
    int flags;
    int n;
    if (fcntl(fd, F_GETFL, &flags) < 0) {
        printf("fcntl(): %s\n", strerror(errno));
        exit(1);
    }

    flags |= O_NONBLOCK;

    if (fcntl(fd, F_SETFL, flags) < 0) {
        printf("fcntl(): %s\n", strerror(errno));
        exit(1);
    }
}


static void epoll_loop(int epoll_fd, int listen_fd)
{
    struct epoll_event *events, *ev, tmp_event;;
    struct sockaddr addr;
    socklen_t len;
    int i, fd;
    char buf[1];

    events = malloc(10 * sizeof(struct epoll_event));
    memset(events, 0, 10 * sizeof(events));
    if (events == NULL) {
        printf("no memory\n");
        exit(1);
    }

    for ( ;; ) {
        int n = epoll_wait(epoll_fd, events, 10, -1);
        if (n < 0) {
            printf("epoll_wait(): %s\n", strerror(errno));
            continue;
        }

        printf("n = %d\n", n);

        for (i = 0; i < n; i++) {
            ev = &events[i];
            if ((ev->events & EPOLLIN)) {
                if (ev->data.fd == listen_fd) {
                    len = sizeof(struct sockaddr);
                    fd = accept(listen_fd, &addr, &len);
                    if (fd < 0) {
                        printf("accept(): %s\n", strerror(errno));
                        continue;
                    }

                    nonblocking(fd);
                    memset(&tmp_event, 0, sizeof(struct epoll_event));
                    tmp_event.events = EPOLLIN|EPOLLRDHUP|EPOLLOUT|EPOLLERR|EPOLLHUP|EPOLLET;
                    tmp_event.data.fd = fd;

                    if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &tmp_event) < 0) {
                        printf("epoll_ctl(): %s\n", strerror(errno));
                        exit(1);
                    }

                } else {
                    if (ev->events & EPOLLRDHUP) {
                        printf("client closed connection!\n");
                    }

                    int n = recv(ev->data.fd, buf, 1, MSG_PEEK);
                    if (n > 0) {
                        printf("rest %d\n", n);
                        continue;
                    }
                }
            }
        }
    }
}

int main() {
    int epoll_fd;
    int listen_fd;
    struct sockaddr_in sock;
    struct epoll_event ev;

    epoll_fd = epoll_create(512);
    if (epoll_fd < 0) {
        printf("epoll_create(): %s\n", strerror(errno));
        exit(1);
    }

    listen_fd = socket(AF_INET, SOCK_STREAM, 0);
    if (listen_fd < 0) {
        printf("socket(): %s\n", strerror(errno));
        exit(1);
    }

    nonblocking(listen_fd);

    memset(&sock, 0, sizeof(struct sockaddr_in));
    sock.sin_family = AF_INET;
    sock.sin_port = htons(LISTEN_PORT);
    inet_aton(LISTEN_HOST, &sock.sin_addr);

    if (bind(listen_fd, (struct sockaddr *) &sock,
             sizeof(struct sockaddr_in))
        < 0)
    {
        printf("bind(): %s\n", strerror(errno));
        exit(1);
    }

    if (listen(listen_fd, 512) < 0) {
        printf("listen(): %s\n", strerror(errno));
        exit(1);
    }

    memset(&ev, 0, sizeof(struct epoll_event));
    ev.events = EPOLLIN|EPOLLOUT|EPOLLHUP|EPOLLERR|EPOLLRDHUP|EPOLLET;
    ev.data.fd = listen_fd;

    if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, listen_fd, &ev) < 0) {
        printf("epoll_ctl(): %s\n", strerror(errno));
        exit(1);
    }

    epoll_loop(epoll_fd, listen_fd);
    return 0;
}