Function parse_bsd_extended_name 

fn parse_bsd_extended_name<'data, R: ReadRef<'data>>(
    digits: &[u8],
    data: R,
    offset: &mut u64,
    size: &mut u64,
) -> Result<&'data [u8], ()>

Digits are a decimal length of the extended name, which is contained in data at offset. Modifies offset and size to start after the extended name.