Function crypt_keyfile_device_read

pub unsafe extern "C" fn crypt_keyfile_device_read(
    cd: *mut crypt_device,
    keyfile: *const c_char,
    key: *mut *mut c_char,
    key_size_read: *mut usize,
    keyfile_offset: u64,
    key_size: usize,
    flags: u32,
) -> c_int