1 /* 2 * Copyright (c) 2009, 2010 3 * Phillip Lougher <phillip (at) squashfs.org.uk> 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License 7 * as published by the Free Software Foundation; either version 2, 8 * or (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 18 * 19 * swap.c 20 */ 21 22 #ifndef linux 23 #define __BYTE_ORDER BYTE_ORDER 24 #define __BIG_ENDIAN BIG_ENDIAN 25 #define __LITTLE_ENDIAN LITTLE_ENDIAN 26 #else 27 #include <endian.h> 28 #endif 29 30 #if __BYTE_ORDER == __BIG_ENDIAN 31 void swap_le16(void *src, void *dest) 32 { 33 unsigned char *s = src; 34 unsigned char *d = dest; 35 36 d[0] = s[1]; 37 d[1] = s[0]; 38 } 39 40 41 void swap_le32(void *src, void *dest) 42 { 43 unsigned char *s = src; 44 unsigned char *d = dest; 45 46 d[0] = s[3]; 47 d[1] = s[2]; 48 d[2] = s[1]; 49 d[3] = s[0]; 50 } 51 52 53 void swap_le64(void *src, void *dest) 54 { 55 unsigned char *s = src; 56 unsigned char *d = dest; 57 58 d[0] = s[7]; 59 d[1] = s[6]; 60 d[2] = s[5]; 61 d[3] = s[4]; 62 d[4] = s[3]; 63 d[5] = s[2]; 64 d[6] = s[1]; 65 d[7] = s[0]; 66 } 67 68 69 unsigned short inswap_le16(unsigned short num) 70 { 71 return (num >> 8) | 72 ((num & 0xff) << 8); 73 } 74 75 76 unsigned int inswap_le32(unsigned int num) 77 { 78 return (num >> 24) | 79 ((num & 0xff0000) >> 8) | 80 ((num & 0xff00) << 8) | 81 ((num & 0xff) << 24); 82 } 83 84 85 long long inswap_le64(long long n) 86 { 87 unsigned long long num = n; 88 89 return (num >> 56) | 90 ((num & 0xff000000000000LL) >> 40) | 91 ((num & 0xff0000000000LL) >> 24) | 92 ((num & 0xff00000000LL) >> 8) | 93 ((num & 0xff000000) << 8) | 94 ((num & 0xff0000) << 24) | 95 ((num & 0xff00) << 40) | 96 ((num & 0xff) << 56); 97 } 98 99 100 #define SWAP_LE_NUM(BITS) \ 101 void swap_le##BITS##_num(void *s, void *d, int n) \ 102 {\ 103 int i;\ 104 for(i = 0; i < n; i++, s += BITS / 8, d += BITS / 8)\ 105 swap_le##BITS(s, d);\ 106 } 107 108 SWAP_LE_NUM(16) 109 SWAP_LE_NUM(32) 110 SWAP_LE_NUM(64) 111 112 #define INSWAP_LE_NUM(BITS, TYPE) \ 113 void inswap_le##BITS##_num(TYPE *s, int n) \ 114 {\ 115 int i;\ 116 for(i = 0; i < n; i++)\ 117 s[i] = inswap_le##BITS(s[i]);\ 118 } 119 120 INSWAP_LE_NUM(16, unsigned short) 121 INSWAP_LE_NUM(32, unsigned int) 122 INSWAP_LE_NUM(64, long long) 123 #endif 124
