fn socket_removal_listener()

in src/enclave_proc/socket.rs [159:211]

• 40 lines of code
• 8 McCabe index (conditional complexity)

fn socket_removal_listener(
    socket_path: PathBuf,
    requested_remove: Arc<AtomicBool>,
    mut socket_inotify: Inotify,
    exit_on_delete: bool,
) {
    let mut buffer = [0u8; 4096];
    let mut done = false;

    debug!("Socket file event listener started for {:?}.", socket_path);

    while !done {
        // Read events.
        let events = socket_inotify
            .read_events_blocking(&mut buffer)
            .map_err(|e| {
                new_nitro_cli_failure!(
                    &format!("Socket removal listener error: {:?}", e),
                    NitroCliErrorEnum::InotifyError
                )
                .set_action("Run Enclave".to_string())
            })
            .ok_or_exit_with_errno(Some("Failed to read inotify events"));

        for event in events {
            // We monitor the DELETE_SELF event, which occurs when the inode is no longer referenced by anybody. We
            // also monitor the IN_ATTRIB event, which gets triggered whenever the inode reference count changes. To
            // make sure this is a deletion, we also verify if the socket file is still present in the file-system.
            if (event.mask.contains(EventMask::ATTRIB)
                || event.mask.contains(EventMask::DELETE_SELF))
                && !socket_path.exists()
            {
                if requested_remove.load(Ordering::SeqCst) {
                    // At this point, the socket is shutting itself down and has notified the
                    // monitoring thread, so we just exit the loop gracefully.
                    debug!("The enclave process socket has deleted itself.");
                    done = true;
                } else {
                    // At this point, the socket has been deleted by an external action, so
                    // we exit forcefully, since there is no longer any way for a CLI instance
                    // to tell the current enclave process to terminate.
                    warn!("The enclave process socket has been deleted!");
                    if exit_on_delete {
                        std::process::exit(1);
                    }
                    done = true;
                }
            }
        }
    }

    debug!("Enclave process socket monitoring is done.");
}