Function lightdm_greeter_ensure_shared_data_dir 

pub unsafe extern "C" fn lightdm_greeter_ensure_shared_data_dir(
    greeter: *mut LightDMGreeter,
    username: *const c_char,
    cancellable: *mut GCancellable,
    callback: GAsyncReadyCallback,
    user_data: gpointer,
)