Function ff_epoll_ctl

lib/ff_epoll.c:30–104

}

int
ff_epoll_ctl(int epfd, int op, int fd, struct epoll_event *event)
{
    /*
     * Since kqueue uses EVFILT_READ and EVFILT_WRITE filters to
     * handle read/write events, so we need two kevents.
     */
    const int changes = 2;
    struct kevent kev[changes];
    int flags = 0;
    int read_flags, write_flags;

    if ((!event && op != EPOLL_CTL_DEL) ||
        (op != EPOLL_CTL_ADD &&
         op != EPOLL_CTL_MOD &&
         op != EPOLL_CTL_DEL)) {
        errno = EINVAL;
        return -1;
    }

    /*
     * EPOLL_CTL_DEL doesn't need to care for event->events.
     */
    if (op == EPOLL_CTL_DEL) {
        EV_SET(&kev[0], fd, EVFILT_READ, EV_DELETE, 0, 0, NULL);
        EV_SET(&kev[1], fd, EVFILT_WRITE, EV_DELETE, 0, 0, NULL);

        return ff_kevent(epfd, kev, changes, NULL, 0, NULL);
    }

    /*
     * FIXME:
     *
     * Kqueue doesn't have edge-triggered mode that exactly
     * same with epoll, the most similar way is setting EV_CLEAR
     * or EV_DISPATCH flag, but there are still some differences.
     *
     * EV_CLEAR:after the event is retrieved by the user,
     *    its state is reset.
     * EV_DISPATCH: disable the event source immediately
     *    after delivery of an event.
     *
     * Here we use EV_CLEAR temporarily.
     *
     */
    if (event->events & EPOLLET) {
        flags |= EV_CLEAR;
    }

    if (event->events & EPOLLONESHOT) {
        flags |= EV_ONESHOT;
    }

    if (op == EPOLL_CTL_ADD) {
        flags |= EV_ADD;
    }

    read_flags = write_flags = flags | EV_DISABLE;