endian.h revision 190854
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/amd64/include/endian.h 190854 2009-04-08 19:10:20Z ed $ 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 40extern "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 __byte_swap_int_var(x) \ 73__extension__ ({ register __uint32_t __X = (x); \ 74 __asm ("bswap %0" : "+r" (__X)); \ 75 __X; }) 76 77#ifdef __OPTIMIZE__ 78 79#define __byte_swap_int_const(x) \ 80 ((((x) & 0xff000000) >> 24) | \ 81 (((x) & 0x00ff0000) >> 8) | \ 82 (((x) & 0x0000ff00) << 8) | \ 83 (((x) & 0x000000ff) << 24)) 84#define __byte_swap_int(x) (__builtin_constant_p(x) ? \ 85 __byte_swap_int_const(x) : __byte_swap_int_var(x)) 86 87#else /* __OPTIMIZE__ */ 88 89#define __byte_swap_int(x) __byte_swap_int_var(x) 90 91#endif /* __OPTIMIZE__ */ 92 93#define __byte_swap_long_var(x) \ 94__extension__ ({ register __uint64_t __X = (x); \ 95 __asm ("bswap %0" : "+r" (__X)); \ 96 __X; }) 97 98#ifdef __OPTIMIZE__ 99 100#define __byte_swap_long_const(x) \ 101 (((x >> 56) | \ 102 ((x >> 40) & 0xff00) | \ 103 ((x >> 24) & 0xff0000) | \ 104 ((x >> 8) & 0xff000000) | \ 105 ((x << 8) & (0xfful << 32)) | \ 106 ((x << 24) & (0xfful << 40)) | \ 107 ((x << 40) & (0xfful << 48)) | \ 108 ((x << 56)))) 109 110#define __byte_swap_long(x) (__builtin_constant_p(x) ? \ 111 __byte_swap_long_const(x) : __byte_swap_long_var(x)) 112 113#else /* __OPTIMIZE__ */ 114 115#define __byte_swap_long(x) __byte_swap_long_var(x) 116 117#endif /* __OPTIMIZE__ */ 118 119static __inline __uint64_t 120__bswap64(__uint64_t _x) 121{ 122 123 return (__byte_swap_long(_x)); 124} 125 126static __inline __uint32_t 127__bswap32(__uint32_t _x) 128{ 129 130 return (__byte_swap_int(_x)); 131} 132 133static __inline __uint16_t 134__bswap16(__uint16_t _x) 135{ 136 return (_x << 8 | _x >> 8); 137} 138 139#define __htonl(x) __bswap32(x) 140#define __htons(x) __bswap16(x) 141#define __ntohl(x) __bswap32(x) 142#define __ntohs(x) __bswap16(x) 143 144#else /* !(__GNUCLIKE_ASM && __GNUCLIKE_BUILTIN_CONSTANT_P) */ 145 146/* 147 * No optimizations are available for this compiler. Fall back to 148 * non-optimized functions by defining the constant usually used to prevent 149 * redefinition. 150 */ 151#define _BYTEORDER_FUNC_DEFINED 152 153#endif /* __GNUCLIKE_ASM && __GNUCLIKE_BUILTIN_CONSTANT_P */ 154 155#ifdef __cplusplus 156} 157#endif 158 159#endif /* !_MACHINE_ENDIAN_H_ */ 160