c_cpp/etc/calc/byteswap.h

   1 /*
   2  * byteswap - byte swapping macros
   3  *
   4  * Copyright (C) 1999  Landon Curt Noll
   5  *
   6  * Calc is open software; you can redistribute it and/or modify it under
   7  * the terms of the version 2.1 of the GNU Lesser General Public License
   8  * as published by the Free Software Foundation.
   9  *
  10  * Calc is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
  13  * Public License for more details.
  14  *
  15  * A copy of version 2.1 of the GNU Lesser General Public License is
  16  * distributed with calc under the filename COPYING-LGPL.  You should have
  17  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  18  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  *
  20  * @(#) $Revision: 30.1 $
  21  * @(#) $Id: byteswap.h,v 30.1 2007/03/16 11:09:46 chongo Exp $
  22  * @(#) $Source: /usr/local/src/bin/calc/RCS/byteswap.h,v $
  23  *
  24  * Under source code control:   1995/10/11 04:44:01
  25  * File existed as early as:    1995
  26  *
  27  * chongo <was here> /\oo/\     http://www.isthe.com/chongo/
  28  * Share and enjoy!  :-)        http://www.isthe.com/chongo/tech/comp/calc/
  29  */
  30
  31
  32 #if !defined(__BYTESWAP_H__)
  33 #define __BYTESWAP_H__
  34
  35
  36 #if defined(CALC_SRC)   /* if we are building from the calc source tree */
  37 # include "longbits.h"
  38 #else
  39 # include <calc/longbits.h>
  40 #endif
  41
  42
  43 /*
  44  * SWAP_B8_IN_B16 - swap 8 bits in 16 bits
  45  *
  46  *      dest    - pointer to where the swapped src wil be put
  47  *      src     - pointer to a 16 bit value to swap
  48  *
  49  * This macro will either switch to the opposite byte sex (Big Endian vs.
  50  * Little Endian) a 16 bit value.
  51  */
  52 #define SWAP_B8_IN_B16(dest, src) (                                     \
  53         *((USB16*)(dest)) =                                             \
  54           (((*((USB16*)(src))) << 8) | ((*((USB16*)(src))) >> 8))       \
  55 )
  56
  57 /*
  58  * SWAP_B16_IN_B32 - swap 16 bits in 32 bits
  59  *
  60  *      dest    - pointer to where the swapped src wil be put
  61  *      src     - pointer to a 32 bit value to swap
  62  */
  63 #define SWAP_B16_IN_B32(dest, src) (                                    \
  64         *((USB32*)(dest)) =                                             \
  65           (((*((USB32*)(src))) << 16) | ((*((USB32*)(src))) >> 16))     \
  66 )
  67
  68 /*
  69  * SWAP_B8_IN_B32 - swap 8 & 16 bits in 32 bits
  70  *
  71  *      dest    - pointer to where the swapped src wil be put
  72  *      src     - pointer to a 32 bit value to swap
  73  *
  74  * This macro will either switch to the opposite byte sex (Big Endian vs.
  75  * Little Endian) a 32 bit value.
  76  */
  77 #define SWAP_B8_IN_B32(dest, src) (                                     \
  78         SWAP_B16_IN_B32(dest, src),                                     \
  79         (*((USB32*)(dest)) =                                            \
  80           ((((*((USB32*)(dest))) & (USB32)0xff00ff00) >> 8) |           \
  81           (((*((USB32*)(dest))) & (USB32)0x00ff00ff) << 8)))            \
  82 )
  83
  84 #if defined(HAVE_B64)
  85
  86 /*
  87  * SWAP_B32_IN_B64 - swap 32 bits in 64 bits
  88  *
  89  *      dest    - pointer to where the swapped src wil be put
  90  *      src     - pointer to a 64 bit value to swap
  91  */
  92 #define SWAP_B32_IN_B64(dest, src) (                                    \
  93         *((USB64*)(dest)) =                                             \
  94           (((*((USB64*)(src))) << 32) | ((*((USB64*)(src))) >> 32))     \
  95 )
  96
  97 /*
  98  * SWAP_B16_IN_B64 - swap 16 & 32 bits in 64 bits
  99  *
 100  *      dest    - pointer to where the swapped src wil be put
 101  *      src     - pointer to a 64 bit value to swap
 102  */
 103 #define SWAP_B16_IN_B64(dest, src) (                                    \
 104         SWAP_B32_IN_B64(dest, src),                                     \
 105         (*((USB64*)(dest)) =                                            \
 106           ((((*((USB64*)(dest))) & (USB64)0xffff0000ffff0000) >> 16) |  \
 107           (((*((USB64*)(dest))) & (USB64)0x0000ffff0000ffff) << 16)))   \
 108 )
 109
 110 /*
 111  * SWAP_B8_IN_B64 - swap 16 & 32 bits in 64 bits
 112  *
 113  *      dest    - pointer to where the swapped src wil be put
 114  *      src     - pointer to a 64 bit value to swap
 115  *
 116  * This macro will either switch to the opposite byte sex (Big Endian vs.
 117  * Little Endian) a 64 bit value.
 118  */
 119 #define SWAP_B8_IN_B64(dest, src) (                                     \
 120         SWAP_B16_IN_B64(dest, src),                                     \
 121         (*((USB64*)(dest)) =                                            \
 122           ((((*((USB64*)(dest))) & (USB64)0xff00ff00ff00ff00) >> 8) |   \
 123           (((*((USB64*)(dest))) & (USB64)0x00ff00ff00ff00ff) << 8)))    \
 124 )
 125
 126 #else /* HAVE_B64 */
 127
 128 /*
 129  * SWAP_B32_IN_B64 - swap 32 bits in 64 bits (simulated by 2 32 bit values)
 130  *
 131  *      dest    - pointer to where the swapped src wil be put
 132  *      src     - pointer to a 64 bit value to swap
 133  */
 134 #define SWAP_B32_IN_B64(dest, src) (                                    \
 135         ((USB32*)(dest))[1] = ((USB32*)(dest))[0],                      \
 136         ((USB32*)(dest))[0] = ((USB32*)(dest))[1]                       \
 137 )
 138
 139 /*
 140  * SWAP_B16_IN_B64 - swap 16 & 32 bits in 64 bits (simulated by 2 32 bit vals)
 141  *
 142  *      dest    - pointer to where the swapped src wil be put
 143  *      src     - pointer to a 64 bit value to swap
 144  */
 145 #define SWAP_B16_IN_B64(dest, src) (                                    \
 146         SWAP_B16_IN_B32(((USB32*)dest)+1, ((USB32*)src)),               \
 147         SWAP_B16_IN_B32(((USB32*)dest), ((USB32*)src)+1)                \
 148 )
 149
 150 /*
 151  * SWAP_B8_IN_B64 - swap 16 & 32 bits in 64 bits (simulated by 2 32 bit vals)
 152  *
 153  *      dest    - pointer to where the swapped src wil be put
 154  *      src     - pointer to a 64 bit value to swap
 155  *
 156  * This macro will either switch to the opposite byte sex (Big Endian vs.
 157  * Little Endian) a 64 bit value.
 158  */
 159 #define SWAP_B8_IN_B64(dest, src) (                                     \
 160         SWAP_B8_IN_B32(((USB32*)dest)+1, ((USB32*)src)),                \
 161         SWAP_B8_IN_B32(((USB32*)dest), ((USB32*)src)+1)                 \
 162 )
 163
 164 #endif /* HAVE_B64 */
 165
 166 #if LONG_BITS == 64
 167
 168 #define SWAP_B32_IN_LONG(dest, src)     SWAP_B32_IN_B64(dest, src)
 169 #define SWAP_B16_IN_LONG(dest, src)     SWAP_B16_IN_B64(dest, src)
 170 #define SWAP_B8_IN_LONG(dest, src)      SWAP_B8_IN_B64(dest, src)
 171
 172 #else /* LONG_BITS == 64 */
 173
 174 #define SWAP_B32_IN_LONG(dest, src)     SWAP_B32_IN_B32(dest, src)
 175 #define SWAP_B16_IN_LONG(dest, src)     SWAP_B16_IN_B32(dest, src)
 176 #define SWAP_B8_IN_LONG(dest, src)      SWAP_B8_IN_B32(dest, src)
 177
 178 #endif /* LONG_BITS == 64 */
 179
 180
 181 #endif /* !__BYTESWAP_H__ */