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31 * @(#)endian.h 8.1 (Berkeley) 6/10/93
35 #ifndef _MACHINE_ENDIAN_H_
36 #define _MACHINE_ENDIAN_H_
38 #include <sys/cdefs.h>
39 #include <sys/_types.h>
42 * Define the order of 32-bit words in 64-bit words.
44 #ifdef __LITTLE_ENDIAN__
45 #define _QUAD_HIGHWORD 1
46 #define _QUAD_LOWWORD 0
48 #define _QUAD_HIGHWORD 0
49 #define _QUAD_LOWWORD 1
53 * GCC defines _BIG_ENDIAN and _LITTLE_ENDIAN equal to __BIG_ENDIAN__
54 * and __LITTLE_ENDIAN__ (resp).
64 * Definitions for byte order, according to byte significance from low
67 #define _LITTLE_ENDIAN 1234 /* LSB first: i386, vax */
68 #define _BIG_ENDIAN 4321 /* MSB first: 68000, ibm, net */
69 #define _PDP_ENDIAN 3412 /* LSB first in word, MSW first in long */
71 #ifdef __LITTLE_ENDIAN__
72 #define _BYTE_ORDER _LITTLE_ENDIAN
74 #define _BYTE_ORDER _BIG_ENDIAN
78 * Deprecated variants that don't have enough underscores to be useful in more
82 #define LITTLE_ENDIAN _LITTLE_ENDIAN
83 #define BIG_ENDIAN _BIG_ENDIAN
84 #define PDP_ENDIAN _PDP_ENDIAN
85 #define BYTE_ORDER _BYTE_ORDER
88 #if defined(__GNUCLIKE_BUILTIN_CONSTANT_P)
89 #define __is_constant(x) __builtin_constant_p(x)
91 #define __is_constant(x) 0
94 #define __bswap16_const(x) ((((__uint16_t)(x) >> 8) & 0xff) | \
95 (((__uint16_t)(x) << 8) & 0xff00))
96 #define __bswap32_const(x) ((((__uint32_t)(x) >> 24) & 0xff) | \
97 (((__uint32_t)(x) >> 8) & 0xff00) | \
98 (((__uint32_t)(x)<< 8) & 0xff0000) | \
99 (((__uint32_t)(x) << 24) & 0xff000000))
100 #define __bswap64_const(x) ((((__uint64_t)(x) >> 56) & 0xff) | \
101 (((__uint64_t)(x) >> 40) & 0xff00) | \
102 (((__uint64_t)(x) >> 24) & 0xff0000) | \
103 (((__uint64_t)(x) >> 8) & 0xff000000) | \
104 (((__uint64_t)(x) << 8) & ((__uint64_t)0xff << 32)) | \
105 (((__uint64_t)(x) << 24) & ((__uint64_t)0xff << 40)) | \
106 (((__uint64_t)(x) << 40) & ((__uint64_t)0xff << 48)) | \
107 (((__uint64_t)(x) << 56) & ((__uint64_t)0xff << 56)))
109 static __inline __uint16_t
110 __bswap16_var(__uint16_t _x)
113 return ((_x >> 8) | ((_x << 8) & 0xff00));
116 static __inline __uint32_t
117 __bswap32_var(__uint32_t _x)
120 return ((_x >> 24) | ((_x >> 8) & 0xff00) | ((_x << 8) & 0xff0000) |
121 ((_x << 24) & 0xff000000));
124 static __inline __uint64_t
125 __bswap64_var(__uint64_t _x)
128 return ((_x >> 56) | ((_x >> 40) & 0xff00) | ((_x >> 24) & 0xff0000) |
129 ((_x >> 8) & 0xff000000) | ((_x << 8) & ((__uint64_t)0xff << 32)) |
130 ((_x << 24) & ((__uint64_t)0xff << 40)) |
131 ((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56)));
134 #define __bswap16(x) ((__uint16_t)(__is_constant(x) ? __bswap16_const(x) : \
136 #define __bswap32(x) (__is_constant(x) ? __bswap32_const(x) : \
138 #define __bswap64(x) (__is_constant(x) ? __bswap64_const(x) : \
141 #ifdef __LITTLE_ENDIAN__
142 #define __htonl(x) (__bswap32((__uint32_t)(x)))
143 #define __htons(x) (__bswap16((__uint16_t)(x)))
144 #define __ntohl(x) (__bswap32((__uint32_t)(x)))
145 #define __ntohs(x) (__bswap16((__uint16_t)(x)))
147 #define __htonl(x) ((__uint32_t)(x))
148 #define __htons(x) ((__uint16_t)(x))
149 #define __ntohl(x) ((__uint32_t)(x))
150 #define __ntohs(x) ((__uint16_t)(x))
153 #endif /* !_MACHINE_ENDIAN_H_ */