| 1 | /* |
| 2 | * Copyright (c) 1982, 1986 Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms are permitted |
| 6 | * provided that the above copyright notice and this paragraph are |
| 7 | * duplicated in all such forms and that any documentation, |
| 8 | * advertising materials, and other materials related to such |
| 9 | * distribution and use acknowledge that the software was developed |
| 10 | * by the University of California, Berkeley. The name of the |
| 11 | * University may not be used to endorse or promote products derived |
| 12 | * from this software without specific prior written permission. |
| 13 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
| 14 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
| 15 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 16 | * |
| 17 | * @(#)tcp_seq.h 7.3 (Berkeley) %G% |
| 18 | */ |
| 19 | |
| 20 | /* |
| 21 | * TCP sequence numbers are 32 bit integers operated |
| 22 | * on with modular arithmetic. These macros can be |
| 23 | * used to compare such integers. |
| 24 | */ |
| 25 | #define SEQ_LT(a,b) ((int)((a)-(b)) < 0) |
| 26 | #define SEQ_LEQ(a,b) ((int)((a)-(b)) <= 0) |
| 27 | #define SEQ_GT(a,b) ((int)((a)-(b)) > 0) |
| 28 | #define SEQ_GEQ(a,b) ((int)((a)-(b)) >= 0) |
| 29 | |
| 30 | /* |
| 31 | * Macros to initialize tcp sequence numbers for |
| 32 | * send and receive from initial send and receive |
| 33 | * sequence numbers. |
| 34 | */ |
| 35 | #define tcp_rcvseqinit(tp) \ |
| 36 | (tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1 |
| 37 | |
| 38 | #define tcp_sendseqinit(tp) \ |
| 39 | (tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp)->snd_up = \ |
| 40 | (tp)->iss |
| 41 | |
| 42 | #define TCP_ISSINCR (125*1024) /* increment for tcp_iss each second */ |
| 43 | |
| 44 | #ifdef KERNEL |
| 45 | tcp_seq tcp_iss; /* tcp initial send seq # */ |
| 46 | #endif |