endian.h revision 156283 
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#7 $
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#include <stdint.h>
39
40/*
41 * Some operating systems do not yet have the more recent endian APIs that
42 * permit encoding to and decoding from byte streams.  For those systems, we
43 * implement local non-optimized versions.
44 */
45
46static __inline uint16_t
47bswap16(uint16_t int16)
48{
49	const unsigned char *from;
50	unsigned char *to;
51	uint16_t t;
52
53	from = (const unsigned char *) &int16;
54	to = (unsigned char *) &t;
55
56	to[0] = from[1];
57	to[1] = from[0];
58
59	return (t);
60}
61
62static __inline uint32_t
63bswap32(uint32_t int32)
64{
65	const unsigned char *from;
66	unsigned char *to;
67	uint32_t t;
68
69	from = (const unsigned char *) &int32;
70	to = (unsigned char *) &t;
71
72	to[0] = from[3];
73	to[1] = from[2];
74	to[2] = from[1];
75	to[3] = from[0];
76
77	return (t);
78}
79
80static __inline uint64_t
81bswap64(uint64_t int64)
82{
83	const unsigned char *from;
84	unsigned char *to;
85	uint64_t t;
86
87	from = (const unsigned char *) &int64;
88	to = (unsigned char *) &t;
89
90	to[0] = from[7];
91	to[1] = from[6];
92	to[2] = from[5];
93	to[3] = from[4];
94	to[4] = from[3];
95	to[5] = from[2];
96	to[6] = from[1];
97	to[7] = from[0];
98
99	return (t);
100}
101
102#if defined(BYTE_ORDER) && !defined(_BYTE_ORDER)
103#define	_BYTE_ORDER	BYTE_ORDER
104#endif
105#if !defined(_BYTE_ORDER)
106#error "Neither BYTE_ORDER nor _BYTE_ORDER defined"
107#endif
108
109#if defined(BIG_ENDIAN) && !defined(_BIG_ENDIAN)
110#define	_BIG_ENDIAN	BIG_ENDIAN
111#endif
112
113#if defined(LITTLE_ENDIAN) && !defined(_LITTLE_ENDIAN)
114#define	_LITTLE_ENDIAN	LITTLE_ENDIAN
115#endif
116
117/*
118 * Host to big endian, host to little endian, big endian to host, and little
119 * endian to host byte order functions as detailed in byteorder(9).
120 */
121#if _BYTE_ORDER == _LITTLE_ENDIAN
122#define	htobe16(x)	bswap16((x))
123#define	htobe32(x)	bswap32((x))
124#define	htobe64(x)	bswap64((x))
125#define	htole16(x)	((uint16_t)(x))
126#define	htole32(x)	((uint32_t)(x))
127#define	htole64(x)	((uint64_t)(x))
128
129#define	be16toh(x)	bswap16((x))
130#define	be32toh(x)	bswap32((x))
131#define	be64toh(x)	bswap64((x))
132#define	le16toh(x)	((uint16_t)(x))
133#define	le32toh(x)	((uint32_t)(x))
134#define	le64toh(x)	((uint64_t)(x))
135#else /* _BYTE_ORDER != _LITTLE_ENDIAN */
136#define	htobe16(x)	((uint16_t)(x))
137#define	htobe32(x)	((uint32_t)(x))
138#define	htobe64(x)	((uint64_t)(x))
139#define	htole16(x)	bswap16((x))
140#define	htole32(x)	bswap32((x))
141#define	htole64(x)	bswap64((x))
142
143#define	be16toh(x)	((uint16_t)(x))
144#define	be32toh(x)	((uint32_t)(x))
145#define	be64toh(x)	((uint64_t)(x))
146#define	le16toh(x)	bswap16((x))
147#define	le32toh(x)	bswap32((x))
148#define	le64toh(x)	bswap64((x))
149#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
150
151/* Alignment-agnostic encode/decode bytestream to/from little/big endian. */
152
153static __inline uint16_t
154be16dec(const void *pp)
155{
156	unsigned char const *p = (unsigned char const *)pp;
157
158	return ((p[0] << 8) | p[1]);
159}
160
161static __inline uint32_t
162be32dec(const void *pp)
163{
164	unsigned char const *p = (unsigned char const *)pp;
165
166	return ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]);
167}
168
169static __inline uint64_t
170be64dec(const void *pp)
171{
172	unsigned char const *p = (unsigned char const *)pp;
173
174	return (((uint64_t)be32dec(p) << 32) | be32dec(p + 4));
175}
176
177static __inline uint16_t
178le16dec(const void *pp)
179{
180	unsigned char const *p = (unsigned char const *)pp;
181
182	return ((p[1] << 8) | p[0]);
183}
184
185static __inline uint32_t
186le32dec(const void *pp)
187{
188	unsigned char const *p = (unsigned char const *)pp;
189
190	return ((p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]);
191}
192
193static __inline uint64_t
194le64dec(const void *pp)
195{
196	unsigned char const *p = (unsigned char const *)pp;
197
198	return (((uint64_t)le32dec(p + 4) << 32) | le32dec(p));
199}
200
201static __inline void
202be16enc(void *pp, uint16_t u)
203{
204	unsigned char *p = (unsigned char *)pp;
205
206	p[0] = (u >> 8) & 0xff;
207	p[1] = u & 0xff;
208}
209
210static __inline void
211be32enc(void *pp, uint32_t u)
212{
213	unsigned char *p = (unsigned char *)pp;
214
215	p[0] = (u >> 24) & 0xff;
216	p[1] = (u >> 16) & 0xff;
217	p[2] = (u >> 8) & 0xff;
218	p[3] = u & 0xff;
219}
220
221static __inline void
222be64enc(void *pp, uint64_t u)
223{
224	unsigned char *p = (unsigned char *)pp;
225
226	be32enc(p, u >> 32);
227	be32enc(p + 4, u & 0xffffffff);
228}
229
230static __inline void
231le16enc(void *pp, uint16_t u)
232{
233	unsigned char *p = (unsigned char *)pp;
234
235	p[0] = u & 0xff;
236	p[1] = (u >> 8) & 0xff;
237}
238
239static __inline void
240le32enc(void *pp, uint32_t u)
241{
242	unsigned char *p = (unsigned char *)pp;
243
244	p[0] = u & 0xff;
245	p[1] = (u >> 8) & 0xff;
246	p[2] = (u >> 16) & 0xff;
247	p[3] = (u >> 24) & 0xff;
248}
249
250static __inline void
251le64enc(void *pp, uint64_t u)
252{
253	unsigned char *p = (unsigned char *)pp;
254
255	le32enc(p, u & 0xffffffff);
256	le32enc(p + 4, u >> 32);
257}
258
259#endif	/* _COMPAT_ENDIAN_H_ */
260