extract.h revision 98524 
1/*
2 * Copyright (c) 1992, 1993, 1994, 1995, 1996
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * @(#) $Header: /tcpdump/master/tcpdump/extract.h,v 1.17 2001/09/17 21:57:52 fenner Exp $ (LBL)
22 */
23
24/* Network to host order macros */
25
26#ifdef LBL_ALIGN
27#define EXTRACT_16BITS(p) \
28	((u_int16_t)*((const u_int8_t *)(p) + 0) << 8 | \
29	(u_int16_t)*((const u_int8_t *)(p) + 1))
30#define EXTRACT_32BITS(p) \
31	((u_int32_t)*((const u_int8_t *)(p) + 0) << 24 | \
32	(u_int32_t)*((const u_int8_t *)(p) + 1) << 16 | \
33	(u_int32_t)*((const u_int8_t *)(p) + 2) << 8 | \
34	(u_int32_t)*((const u_int8_t *)(p) + 3))
35#else
36#define EXTRACT_16BITS(p) \
37	((u_int16_t)ntohs(*(const u_int16_t *)(p)))
38#define EXTRACT_32BITS(p) \
39	((u_int32_t)ntohl(*(const u_int32_t *)(p)))
40#endif
41
42#define EXTRACT_24BITS(p) \
43	((u_int32_t)*((const u_int8_t *)(p) + 0) << 16 | \
44	(u_int32_t)*((const u_int8_t *)(p) + 1) << 8 | \
45	(u_int32_t)*((const u_int8_t *)(p) + 2))
46
47/* Little endian protocol host order macros */
48
49#define EXTRACT_LE_8BITS(p) (*(p))
50#define EXTRACT_LE_16BITS(p) \
51	((u_int16_t)*((const u_int8_t *)(p) + 1) << 8 | \
52	(u_int16_t)*((const u_int8_t *)(p) + 0))
53#define EXTRACT_LE_32BITS(p) \
54	((u_int32_t)*((const u_int8_t *)(p) + 3) << 24 | \
55	(u_int32_t)*((const u_int8_t *)(p) + 2) << 16 | \
56	(u_int32_t)*((const u_int8_t *)(p) + 1) << 8 | \
57	(u_int32_t)*((const u_int8_t *)(p) + 0))
58