Function ocb_done_decrypt 

pub unsafe extern "C" fn ocb_done_decrypt(
    ocb: *mut ocb_state,
    ct: *const c_uchar,
    ctlen: c_ulong,
    pt: *mut c_uchar,
    tag: *const c_uchar,
    taglen: c_ulong,
    stat: *mut c_int,
) -> c_int