Line data Source code
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 : * 4. Neither the name of the University nor the names of its contributors
14 : * may be used to endorse or promote products derived from this software
15 : * without specific prior written permission.
16 : *
17 : * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 : * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 : * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 : * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 : * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 : * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 : * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 : * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 : * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 : * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 : * SUCH DAMAGE.
28 : *
29 : * @(#)endian.h 7.8 (Berkeley) 4/3/91
30 : * $FreeBSD: head/sys/x86/include/endian.h 233684 2012-03-29 23:31:48Z dim $
31 : */
32 :
33 : #ifndef _MACHINE_ENDIAN_H_
34 : #define _MACHINE_ENDIAN_H_
35 :
36 : #include <sys/cdefs.h>
37 : #include <sys/_types.h>
38 :
39 : /*
40 : * Define the order of 32-bit words in 64-bit words.
41 : */
42 : #define _QUAD_HIGHWORD 1
43 : #define _QUAD_LOWWORD 0
44 :
45 : /*
46 : * Definitions for byte order, according to byte significance from low
47 : * address to high.
48 : */
49 : #define _LITTLE_ENDIAN 1234 /* LSB first: i386, vax */
50 : #define _BIG_ENDIAN 4321 /* MSB first: 68000, ibm, net */
51 : #define _PDP_ENDIAN 3412 /* LSB first in word, MSW first in long */
52 :
53 : #define _BYTE_ORDER _LITTLE_ENDIAN
54 :
55 : /*
56 : * Deprecated variants that don't have enough underscores to be useful in more
57 : * strict namespaces.
58 : */
59 : #if __BSD_VISIBLE
60 : #define LITTLE_ENDIAN _LITTLE_ENDIAN
61 : #define BIG_ENDIAN _BIG_ENDIAN
62 : #define PDP_ENDIAN _PDP_ENDIAN
63 : #define BYTE_ORDER _BYTE_ORDER
64 : #endif
65 :
66 : #define __bswap16_gen(x) (__uint16_t)((x) << 8 | (x) >> 8)
67 : #define __bswap32_gen(x) \
68 : (((__uint32_t)__bswap16((x) & 0xffff) << 16) | __bswap16((x) >> 16))
69 : #define __bswap64_gen(x) \
70 : (((__uint64_t)__bswap32((x) & 0xffffffff) << 32) | __bswap32((x) >> 32))
71 :
72 : #ifdef __GNUCLIKE_BUILTIN_CONSTANT_P
73 : #define __bswap16(x) \
74 : ((__uint16_t)(__builtin_constant_p(x) ? \
75 : __bswap16_gen((__uint16_t)(x)) : __bswap16_var(x)))
76 : #define __bswap32(x) \
77 : (__builtin_constant_p(x) ? \
78 : __bswap32_gen((__uint32_t)(x)) : __bswap32_var(x))
79 : #define __bswap64(x) \
80 : (__builtin_constant_p(x) ? \
81 : __bswap64_gen((__uint64_t)(x)) : __bswap64_var(x))
82 : #else
83 : /* XXX these are broken for use in static initializers. */
84 : #define __bswap16(x) __bswap16_var(x)
85 : #define __bswap32(x) __bswap32_var(x)
86 : #define __bswap64(x) __bswap64_var(x)
87 : #endif
88 :
89 : /* These are defined as functions to avoid multiple evaluation of x. */
90 :
91 : static __inline __uint16_t
92 0 : __bswap16_var(__uint16_t _x)
93 : {
94 :
95 0 : return (__bswap16_gen(_x));
96 : }
97 :
98 : static __inline __uint32_t
99 : __bswap32_var(__uint32_t _x)
100 : {
101 :
102 : #ifdef __GNUCLIKE_ASM
103 : __asm("bswap %0" : "+r" (_x));
104 : return (_x);
105 : #else
106 : return (__bswap32_gen(_x));
107 : #endif
108 : }
109 :
110 : static __inline __uint64_t
111 : __bswap64_var(__uint64_t _x)
112 : {
113 :
114 : #if defined(__amd64__) && defined(__GNUCLIKE_ASM)
115 : __asm("bswap %0" : "+r" (_x));
116 : return (_x);
117 : #else
118 : /*
119 : * It is important for the optimizations that the following is not
120 : * really generic, but expands to 2 __bswap32_var()'s.
121 : */
122 : return (__bswap64_gen(_x));
123 : #endif
124 : }
125 :
126 : #define __htonl(x) __bswap32(x)
127 : #define __htons(x) __bswap16(x)
128 : #define __ntohl(x) __bswap32(x)
129 : #define __ntohs(x) __bswap16(x)
130 :
131 : #endif /* !_MACHINE_ENDIAN_H_ */
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