xref: /csrg-svn/sys/netinet/tcp_seq.h (revision 44487)
123192Smckusick /*
229151Smckusick  * Copyright (c) 1982, 1986 Regents of the University of California.
332789Sbostic  * All rights reserved.
423192Smckusick  *
5*44487Sbostic  * %sccs.include.redist.c%
632789Sbostic  *
7*44487Sbostic  *	@(#)tcp_seq.h	7.4 (Berkeley) 06/28/90
823192Smckusick  */
95124Swnj 
105124Swnj /*
115124Swnj  * TCP sequence numbers are 32 bit integers operated
125124Swnj  * on with modular arithmetic.  These macros can be
135124Swnj  * used to compare such integers.
145124Swnj  */
155124Swnj #define	SEQ_LT(a,b)	((int)((a)-(b)) < 0)
165124Swnj #define	SEQ_LEQ(a,b)	((int)((a)-(b)) <= 0)
175124Swnj #define	SEQ_GT(a,b)	((int)((a)-(b)) > 0)
185124Swnj #define	SEQ_GEQ(a,b)	((int)((a)-(b)) >= 0)
195124Swnj 
205124Swnj /*
215124Swnj  * Macros to initialize tcp sequence numbers for
225124Swnj  * send and receive from initial send and receive
235124Swnj  * sequence numbers.
245124Swnj  */
255124Swnj #define	tcp_rcvseqinit(tp) \
2625203Skarels 	(tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1
275124Swnj 
285124Swnj #define	tcp_sendseqinit(tp) \
295124Swnj 	(tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \
305124Swnj 	    (tp)->iss
315124Swnj 
3225204Skarels #define	TCP_ISSINCR	(125*1024)	/* increment for tcp_iss each second */
335124Swnj 
345124Swnj #ifdef KERNEL
355124Swnj tcp_seq	tcp_iss;		/* tcp initial send seq # */
365124Swnj #endif
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