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 * $FreeBSD$ 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 #ifdef __cplusplus 40 extern "C" { 41 #endif 42 43 /* 44 * Define the order of 32-bit words in 64-bit words. 45 */ 46 #define _QUAD_HIGHWORD 1 47 #define _QUAD_LOWWORD 0 48 49 /* 50 * Definitions for byte order, according to byte significance from low 51 * address to high. 52 */ 53 #define _LITTLE_ENDIAN 1234 /* LSB first: i386, vax */ 54 #define _BIG_ENDIAN 4321 /* MSB first: 68000, ibm, net */ 55 #define _PDP_ENDIAN 3412 /* LSB first in word, MSW first in long */ 56 57 #define _BYTE_ORDER _LITTLE_ENDIAN 58 59 /* 60 * Deprecated variants that don't have enough underscores to be useful in more 61 * strict namespaces. 62 */ 63 #if __BSD_VISIBLE 64 #define LITTLE_ENDIAN _LITTLE_ENDIAN 65 #define BIG_ENDIAN _BIG_ENDIAN 66 #define PDP_ENDIAN _PDP_ENDIAN 67 #define BYTE_ORDER _BYTE_ORDER 68 #endif 69 70 #if defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE_BUILTIN_CONSTANT_P) 71 72 #define __bswap64_const(_x) \ 73 (((_x) >> 56) | \ 74 (((_x) >> 40) & (0xffULL << 8)) | \ 75 (((_x) >> 24) & (0xffULL << 16)) | \ 76 (((_x) >> 8) & (0xffULL << 24)) | \ 77 (((_x) << 8) & (0xffULL << 32)) | \ 78 (((_x) << 24) & (0xffULL << 40)) | \ 79 (((_x) << 40) & (0xffULL << 48)) | \ 80 ((_x) << 56)) 81 82 #define __bswap32_const(_x) \ 83 (((_x) >> 24) | \ 84 (((_x) & (0xff << 16)) >> 8) | \ 85 (((_x) & (0xff << 8)) << 8) | \ 86 ((_x) << 24)) 87 88 #define __bswap16_const(_x) (__uint16_t)((_x) << 8 | (_x) >> 8) 89 90 static __inline __uint64_t 91 __bswap64_var(__uint64_t __x) 92 { 93 94 return __bswap64_const(__x); 95 } 96 97 98 static __inline __uint32_t 99 __bswap32_var(__uint32_t _x) 100 { 101 102 __asm ("bswap %0" : "+r" (_x)); 103 return (_x); 104 } 105 106 static __inline __uint16_t 107 __bswap16_var(__uint16_t _x) 108 { 109 110 return (__bswap16_const(_x)); 111 } 112 113 #define __bswap64(_x) \ 114 (__builtin_constant_p(_x) ? \ 115 __bswap64_const((__uint64_t)(_x)) : __bswap64_var(_x)) 116 117 #define __bswap32(_x) \ 118 (__builtin_constant_p(_x) ? \ 119 __bswap32_const((__uint32_t)(_x)) : __bswap32_var(_x)) 120 121 #define __bswap16(_x) \ 122 (__builtin_constant_p(_x) ? \ 123 __bswap16_const((__uint16_t)(_x)) : __bswap16_var(_x)) 124 125 #define __htonl(x) __bswap32(x) 126 #define __htons(x) __bswap16(x) 127 #define __ntohl(x) __bswap32(x) 128 #define __ntohs(x) __bswap16(x) 129 130 #else /* !(__GNUCLIKE_ASM && __GNUCLIKE_BUILTIN_CONSTANT_P) */ 131 132 /* 133 * No optimizations are available for this compiler. Fall back to 134 * non-optimized functions by defining the constant usually used to prevent 135 * redefinition. 136 */ 137 #define _BYTEORDER_FUNC_DEFINED 138 139 #endif /* __GNUCLIKE_ASM && __GNUCLIKE_BUILTIN_CONSTANT_P */ 140 141 #ifdef __cplusplus 142 } 143 #endif 144 145 #endif /* !_MACHINE_ENDIAN_H_ */ 146