/* DCtcp.h */

/* EMACS_MODES: c !fill */

/* Definitions for Alto TCP translation */

#define	MAXTCPBUF	512		/* max. buffer size for now */

typedef	long	seq_t;			/* sequence numbers */

struct	tcp	{			/* a tcp header */
	unshort	tc_srcp;		/* source port */
	unshort	tc_dstp;		/* dest port */
	seq_t	tc_seq;			/* sequence number */
	seq_t	tc_ack;			/* acknowledgement number */
	int	tc_fin : 1;		/* fin bit */
	int	tc_syn : 1;		/* syn bit */
	int	tc_rst : 1;		/* reset bit */
	int	tc_psh : 1;		/* push bit */
	int	tc_fack : 1;		/* ack valid */
	int	tc_furg : 1;		/* urgent ptr. valid */
	int	tc_uu2 : 2;		/* unused */
	int	tc_uu1 : 4;		/* unused */
	int	tc_thl : 4;		/* tcp header length */
	short	tc_win;			/* window */
	unshort	tc_cksum;		/* checksum */
	unshort	tc_urg;			/* urgent pointer */
};


struct	tcpph	{			/* psuedo-header */
	in_name	tp_src;			/* source addr */
	in_name	tp_dst;			/* dest addr */
	char	tp_zero;		/* always 0 */
	char	tp_pro;			/* protocol */
	int	tp_len;			/* length */
};


#define	SEQ_GT(a, b)	(((a) - (b)) > 0)
#define	SEQ_GE(a, b)	(((a) - (b) >= 0)
#define	SEQ_EQ(a, b)	((a) == (b))
#define	SEQ_NE(a, b)	((a) != (b))
#define	SEQ_LE(a, b)	(((a) - (b)) <= 0)
#define	SEQ_LT(a, b)	(((a) - (b)) < 0)


#define	TCPPROT		6		/* tcp protocol number */