endian.h revision 103814
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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)endian.h 7.8 (Berkeley) 4/3/91 34 * $FreeBSD: head/sys/amd64/include/endian.h 103814 2002-09-23 04:32:17Z mike $ 35 */ 36 37#ifndef _MACHINE_ENDIAN_H_ 38#define _MACHINE_ENDIAN_H_ 39 40#include <sys/cdefs.h> 41#include <sys/_types.h> 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#ifdef __GNUC__ 71 72#define __word_swap_int(x) \ 73__extension__ ({ register __uint32_t __X = (x); \ 74 __asm ("rorl $16, %0" : "+r" (__X)); \ 75 __X; }) 76 77#if defined(_KERNEL) 78#define __byte_swap_int(x) \ 79__extension__ ({ register __uint32_t __X = (x); \ 80 __asm ("bswap %0" : "+r" (__X)); \ 81 __X; }) 82#endif 83 84#define __byte_swap_word(x) \ 85__extension__ ({ register __uint16_t __X = (x); \ 86 __asm ("xchgb %h0, %b0" : "+q" (__X)); \ 87 __X; }) 88 89static __inline __uint64_t 90__bswap64(__uint64_t _x) 91{ 92 return ((_x >> 56) | ((_x >> 40) & 0xff00) | ((_x >> 24) & 0xff0000) | 93 ((_x >> 8) & 0xff000000) | ((_x << 8) & ((__uint64_t)0xff << 32)) | 94 ((_x << 24) & ((__uint64_t)0xff << 40)) | 95 ((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56))); 96} 97 98static __inline __uint32_t 99__bswap32(__uint32_t _x) 100{ 101 102 return (__byte_swap_int(_x)); 103} 104 105static __inline __uint16_t 106__bswap16(__uint16_t _x) 107{ 108 109 return (__byte_swap_word(_x)); 110} 111 112#define __htonl(x) __bswap32(x) 113#define __htons(x) __bswap16(x) 114#define __ntohl(x) __bswap32(x) 115#define __ntohs(x) __bswap16(x) 116 117#else /* !__GNUC__ */ 118 119/* 120 * No optimizations are available for this compiler. Fall back to 121 * non-optimized functions by defining the constant usually used to prevent 122 * redefinition. 123 */ 124#define _BYTEORDER_FUNC_DEFINED 125 126#endif /* __GNUC__ */ 127 128#endif /* !_MACHINE_ENDIAN_H_ */ 129