xref: /freebsd/tools/build/cross-build/include/linux/sys/endian.h (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright 2018-2020 Alex Richardson <arichardson@FreeBSD.org>
5  *
6  * This software was developed by SRI International and the University of
7  * Cambridge Computer Laboratory (Department of Computer Science and
8  * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
9  * DARPA SSITH research programme.
10  *
11  * This software was developed by SRI International and the University of
12  * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
13  * ("CTSRD"), as part of the DARPA CRASH research programme.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 #pragma once
37 
38 #if __has_include_next(<sys/endian.h>)
39 #include_next <sys/endian.h>
40 #endif
41 
42 #if __has_include(<endian.h>)
43 #include <endian.h>
44 #endif
45 
46 /* Linux uses a double underscore, FreeBSD a single one */
47 #define _LITTLE_ENDIAN __LITTLE_ENDIAN
48 #define _BIG_ENDIAN __BIG_ENDIAN
49 #define _BYTE_ORDER __BYTE_ORDER
50 
51 /*
52  * Ensure all these are constant expressions (which is not the case for some
53  * of the glibc versions depending on compiler optimization level)
54  */
55 
56 #undef bswap64
57 #define bswap64(a) __builtin_bswap64(a)
58 
59 #undef bswap32
60 #define bswap32(a) __builtin_bswap32(a)
61 
62 #undef bswap16
63 #define bswap16(a) __builtin_bswap16(a)
64 
65 #undef __bswap_64
66 #define __bswap_64(a) __builtin_bswap64(a)
67 
68 #undef __bswap_32
69 #define __bswap_32(a) __builtin_bswap32(a)
70 
71 #undef __bswap_16
72 #define __bswap_16(a) __builtin_bswap16(a)
73 
74 /* Alignment-agnostic encode/decode bytestream to/from little/big endian. */
75 
76 static __inline uint16_t
77 be16dec(const void *pp)
78 {
79 	uint8_t const *p = (uint8_t const *)pp;
80 
81 	return ((p[0] << 8) | p[1]);
82 }
83 
84 static __inline uint32_t
85 be32dec(const void *pp)
86 {
87 	uint8_t const *p = (uint8_t const *)pp;
88 
89 	return (((unsigned)p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]);
90 }
91 
92 static __inline uint64_t
93 be64dec(const void *pp)
94 {
95 	uint8_t const *p = (uint8_t const *)pp;
96 
97 	return (((uint64_t)be32dec(p) << 32) | be32dec(p + 4));
98 }
99 
100 static __inline uint16_t
101 le16dec(const void *pp)
102 {
103 	uint8_t const *p = (uint8_t const *)pp;
104 
105 	return ((p[1] << 8) | p[0]);
106 }
107 
108 static __inline uint32_t
109 le32dec(const void *pp)
110 {
111 	uint8_t const *p = (uint8_t const *)pp;
112 
113 	return (((unsigned)p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]);
114 }
115 
116 static __inline uint64_t
117 le64dec(const void *pp)
118 {
119 	uint8_t const *p = (uint8_t const *)pp;
120 
121 	return (((uint64_t)le32dec(p + 4) << 32) | le32dec(p));
122 }
123 
124 static __inline void
125 be16enc(void *pp, uint16_t u)
126 {
127 	uint8_t *p = (uint8_t *)pp;
128 
129 	p[0] = (u >> 8) & 0xff;
130 	p[1] = u & 0xff;
131 }
132 
133 static __inline void
134 be32enc(void *pp, uint32_t u)
135 {
136 	uint8_t *p = (uint8_t *)pp;
137 
138 	p[0] = (u >> 24) & 0xff;
139 	p[1] = (u >> 16) & 0xff;
140 	p[2] = (u >> 8) & 0xff;
141 	p[3] = u & 0xff;
142 }
143 
144 static __inline void
145 be64enc(void *pp, uint64_t u)
146 {
147 	uint8_t *p = (uint8_t *)pp;
148 
149 	be32enc(p, (uint32_t)(u >> 32));
150 	be32enc(p + 4, (uint32_t)(u & 0xffffffffU));
151 }
152 
153 static __inline void
154 le16enc(void *pp, uint16_t u)
155 {
156 	uint8_t *p = (uint8_t *)pp;
157 
158 	p[0] = u & 0xff;
159 	p[1] = (u >> 8) & 0xff;
160 }
161 
162 static __inline void
163 le32enc(void *pp, uint32_t u)
164 {
165 	uint8_t *p = (uint8_t *)pp;
166 
167 	p[0] = u & 0xff;
168 	p[1] = (u >> 8) & 0xff;
169 	p[2] = (u >> 16) & 0xff;
170 	p[3] = (u >> 24) & 0xff;
171 }
172 
173 static __inline void
174 le64enc(void *pp, uint64_t u)
175 {
176 	uint8_t *p = (uint8_t *)pp;
177 
178 	le32enc(p, (uint32_t)(u & 0xffffffffU));
179 	le32enc(p + 4, (uint32_t)(u >> 32));
180 }
181