FSM_OPTLEN
dec->rejend += fsm_opt(dec->rejend, FSM_OPTLEN - (dec->rejend - dec->rej), o);
dec->ackend += fsm_opt(dec->ackend, FSM_OPTLEN - (dec->ackend - dec->ack), o);
dec->nakend += fsm_opt(dec->nakend, FSM_OPTLEN - (dec->nakend - dec->nak), o);
u_char ack[FSM_OPTLEN], *ackend;
u_char nak[FSM_OPTLEN], *nakend;
u_char rej[FSM_OPTLEN], *rejend;