You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: listener_source.rs
    path of file: ./repos/smithay/src/wayland/security_context
    
    the code of the file until where you have to start completion: // TODO calloop source
// - poll POLLHUP/POLLIN on close_fd
// - poll for accept

use calloop::{
    generic::Generic, EventSource
    
    pub(super) fn new(listen_fd: UnixListener, close_fd: OwnedFd) -> io::Result<Self> {
        listen_fd.set_nonblocking(true)?;
        let listen_fd = Generic::new(listen_fd, Interest::READ, Mode::Level);
        // close_fd.set_nonblocking(true);
        // XXX POLLHUP
        let close_fd = Generic::new(close_fd, Interest::READ, Mode::Level);
        Ok(Self { listen_fd, close_fd })
    }