endian.h revision 243750 
1/*-
2 * Copyright (c) 2002 Thomas Moestl <tmm@FreeBSD.org>
3 * Copyright (c) 2005 Robert N. M. Watson
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * Derived from FreeBSD src/sys/sys/endian.h:1.6.
28 * $P4: //depot/projects/trustedbsd/openbsm/compat/endian.h#10 $
29 */
30
31#ifndef _COMPAT_ENDIAN_H_
32#define _COMPAT_ENDIAN_H_
33
34/*
35 * Some systems will have the uint/int types defined here already, others
36 * will need stdint.h.
37 */
38#ifdef HAVE_STDINT_H
39#include <stdint.h>
40#endif
41
42/*
43 * Some operating systems do not yet have the more recent endian APIs that
44 * permit encoding to and decoding from byte streams.  For those systems, we
45 * implement local non-optimized versions.
46 */
47
48static __inline uint16_t
49bswap16(uint16_t int16)
50{
51	const unsigned char *from;
52	unsigned char *to;
53	uint16_t t;
54
55	from = (const unsigned char *) &int16;
56	to = (unsigned char *) &t;
57
58	to[0] = from[1];
59	to[1] = from[0];
60
61	return (t);
62}
63
64static __inline uint32_t
65bswap32(uint32_t int32)
66{
67	const unsigned char *from;
68	unsigned char *to;
69	uint32_t t;
70
71	from = (const unsigned char *) &int32;
72	to = (unsigned char *) &t;
73
74	to[0] = from[3];
75	to[1] = from[2];
76	to[2] = from[1];
77	to[3] = from[0];
78
79	return (t);
80}
81
82static __inline uint64_t
83bswap64(uint64_t int64)
84{
85	const unsigned char *from;
86	unsigned char *to;
87	uint64_t t;
88
89	from = (const unsigned char *) &int64;
90	to = (unsigned char *) &t;
91
92	to[0] = from[7];
93	to[1] = from[6];
94	to[2] = from[5];
95	to[3] = from[4];
96	to[4] = from[3];
97	to[5] = from[2];
98	to[6] = from[1];
99	to[7] = from[0];
100
101	return (t);
102}
103
104#if defined(BYTE_ORDER) && !defined(_BYTE_ORDER)
105#define	_BYTE_ORDER	BYTE_ORDER
106#endif
107#if !defined(_BYTE_ORDER)
108#error "Neither BYTE_ORDER nor _BYTE_ORDER defined"
109#endif
110
111#if defined(BIG_ENDIAN) && !defined(_BIG_ENDIAN)
112#define	_BIG_ENDIAN	BIG_ENDIAN
113#endif
114
115#if defined(LITTLE_ENDIAN) && !defined(_LITTLE_ENDIAN)
116#define	_LITTLE_ENDIAN	LITTLE_ENDIAN
117#endif
118
119/* XXX: Hack. */
120#ifndef htobe16
121/*
122 * Host to big endian, host to little endian, big endian to host, and little
123 * endian to host byte order functions as detailed in byteorder(9).
124 */
125#if _BYTE_ORDER == _LITTLE_ENDIAN
126#define	htobe16(x)	bswap16((x))
127#define	htobe32(x)	bswap32((x))
128#define	htobe64(x)	bswap64((x))
129#define	htole16(x)	((uint16_t)(x))
130#define	htole32(x)	((uint32_t)(x))
131#define	htole64(x)	((uint64_t)(x))
132
133#define	be16toh(x)	bswap16((x))
134#define	be32toh(x)	bswap32((x))
135#define	be64toh(x)	bswap64((x))
136#define	le16toh(x)	((uint16_t)(x))
137#define	le32toh(x)	((uint32_t)(x))
138#define	le64toh(x)	((uint64_t)(x))
139#else /* _BYTE_ORDER != _LITTLE_ENDIAN */
140#define	htobe16(x)	((uint16_t)(x))
141#define	htobe32(x)	((uint32_t)(x))
142#define	htobe64(x)	((uint64_t)(x))
143#define	htole16(x)	bswap16((x))
144#define	htole32(x)	bswap32((x))
145#define	htole64(x)	bswap64((x))
146
147#define	be16toh(x)	((uint16_t)(x))
148#define	be32toh(x)	((uint32_t)(x))
149#define	be64toh(x)	((uint64_t)(x))
150#define	le16toh(x)	bswap16((x))
151#define	le32toh(x)	bswap32((x))
152#define	le64toh(x)	bswap64((x))
153#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
154#endif
155
156#endif	/* _COMPAT_ENDIAN_H_ */
157