endian.h revision 99129 
1/*-
2 * Copyright (c) 1987, 1991 Regents of the University of California.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	@(#)endian.h	7.8 (Berkeley) 4/3/91
34 * $FreeBSD: head/sys/amd64/include/endian.h 99129 2002-06-30 08:57:17Z obrien $
35 */
36
37#ifndef _MACHINE_ENDIAN_H_
38#define	_MACHINE_ENDIAN_H_
39
40#include <sys/cdefs.h>
41#include <machine/ansi.h>
42
43/*
44 * Define the order of 32-bit words in 64-bit words.
45 */
46#define	_QUAD_HIGHWORD 1
47#define	_QUAD_LOWWORD 0
48
49/*
50 * Definitions for byte order, according to byte significance from low
51 * address to high.
52 */
53#define	_LITTLE_ENDIAN	1234	/* LSB first: i386, vax */
54#define	_BIG_ENDIAN	4321	/* MSB first: 68000, ibm, net */
55#define	_PDP_ENDIAN	3412	/* LSB first in word, MSW first in long */
56
57#define	_BYTE_ORDER	_LITTLE_ENDIAN
58
59/*
60 * Deprecated variants that don't have enough underscores to be useful in more
61 * strict namespaces.
62 */
63#if __BSD_VISIBLE
64#define	LITTLE_ENDIAN	_LITTLE_ENDIAN
65#define	BIG_ENDIAN	_BIG_ENDIAN
66#define	PDP_ENDIAN	_PDP_ENDIAN
67#define	BYTE_ORDER	_BYTE_ORDER
68#endif
69
70#ifdef __GNUC__
71
72#define __word_swap_int(x) \
73__extension__ ({ register __uint32_t __X = (x); \
74   __asm ("rorl $16, %0" : "+r" (__X)); \
75   __X; })
76
77#if defined(_KERNEL)
78#define __byte_swap_int(x) \
79__extension__ ({ register __uint32_t __X = (x); \
80   __asm ("bswap %0" : "+r" (__X)); \
81   __X; })
82#endif
83
84#define __byte_swap_word(x) \
85__extension__ ({ register __uint16_t __X = (x); \
86   __asm ("xchgb %h0, %b0" : "+q" (__X)); \
87   __X; })
88
89static __inline __uint64_t
90__bswap64(__uint64_t _x)
91{
92	return ((_x >> 56) | ((_x >> 40) & 0xff00) | ((_x >> 24) & 0xff0000) |
93	    ((_x >> 8) & 0xff000000) | ((_x << 8) & ((__uint64_t)0xff << 32)) |
94	    ((_x << 24) & ((__uint64_t)0xff << 40)) |
95	    ((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56)));
96}
97
98static __inline __uint32_t
99__bswap32(__uint32_t _x)
100{
101
102	return (__byte_swap_int(_x));
103}
104
105static __inline __uint16_t
106__bswap16(__uint16_t _x)
107{
108
109	return (__byte_swap_word(_x));
110}
111
112#endif /* __GNUC__ */
113
114#define	__htonl(x)	__bswap32(x)
115#define	__htons(x)	__bswap16(x)
116#define	__ntohl(x)	__bswap32(x)
117#define	__ntohs(x)	__bswap16(x)
118
119#endif /* !_MACHINE_ENDIAN_H_ */
120