release/src/router/lzo/src/lzo_crc.c

   1 /* lzo_crc.c -- crc checksum for the the LZO library
   2
   3    This file is part of the LZO real-time data compression library.
   4
   5    Copyright (C) 2011 Markus Franz Xaver Johannes Oberhumer
   6    Copyright (C) 2010 Markus Franz Xaver Johannes Oberhumer
   7    Copyright (C) 2009 Markus Franz Xaver Johannes Oberhumer
   8    Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
   9    Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
  10    Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
  11    Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
  12    Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
  13    Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
  14    Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
  15    Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
  16    Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
  17    Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
  18    Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
  19    Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
  20    Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
  21    All Rights Reserved.
  22
  23    The LZO library is free software; you can redistribute it and/or
  24    modify it under the terms of the GNU General Public License as
  25    published by the Free Software Foundation; either version 2 of
  26    the License, or (at your option) any later version.
  27
  28    The LZO library is distributed in the hope that it will be useful,
  29    but WITHOUT ANY WARRANTY; without even the implied warranty of
  30    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  31    GNU General Public License for more details.
  32
  33    You should have received a copy of the GNU General Public License
  34    along with the LZO library; see the file COPYING.
  35    If not, write to the Free Software Foundation, Inc.,
  36    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  37
  38    Markus F.X.J. Oberhumer
  39    <markus@oberhumer.com>
  40    http://www.oberhumer.com/opensource/lzo/
  41  */
  42
  43
  44 #include "lzo_conf.h"
  45
  46
  47 /***********************************************************************
  48 // crc32 checksum
  49 // adapted from free code by Mark Adler <madler@alumni.caltech.edu>
  50 // see http://www.zlib.org/
  51 ************************************************************************/
  52
  53 static const lzo_uint32 lzo_crc32_table[256] = {
  54   0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
  55   0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
  56   0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
  57   0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
  58   0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
  59   0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
  60   0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
  61   0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
  62   0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
  63   0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
  64   0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
  65   0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
  66   0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
  67   0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
  68   0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
  69   0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
  70   0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
  71   0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
  72   0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
  73   0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
  74   0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
  75   0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
  76   0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
  77   0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
  78   0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
  79   0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
  80   0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
  81   0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
  82   0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
  83   0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
  84   0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
  85   0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
  86   0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
  87   0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
  88   0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
  89   0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
  90   0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
  91   0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
  92   0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
  93   0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
  94   0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
  95   0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
  96   0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
  97   0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
  98   0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
  99   0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
 100   0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
 101   0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
 102   0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
 103   0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
 104   0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
 105   0x2d02ef8dL
 106 };
 107
 108
 109 LZO_PUBLIC(const lzo_uint32p)
 110 lzo_get_crc32_table(void)
 111 {
 112     return lzo_crc32_table;
 113 }
 114
 115
 116 #if 1
 117 #define LZO_DO1(buf,i) \
 118     crc = table[((unsigned)crc ^ buf[i]) & 0xff] ^ (crc >> 8)
 119 #else
 120 #define LZO_DO1(buf,i) \
 121     crc = table[(unsigned char)((unsigned char)crc ^ buf[i])] ^ (crc >> 8)
 122 #endif
 123 #define LZO_DO2(buf,i)  LZO_DO1(buf,i); LZO_DO1(buf,i+1);
 124 #define LZO_DO4(buf,i)  LZO_DO2(buf,i); LZO_DO2(buf,i+2);
 125 #define LZO_DO8(buf,i)  LZO_DO4(buf,i); LZO_DO4(buf,i+4);
 126 #define LZO_DO16(buf,i) LZO_DO8(buf,i); LZO_DO8(buf,i+8);
 127
 128
 129 LZO_PUBLIC(lzo_uint32)
 130 lzo_crc32(lzo_uint32 c, const lzo_bytep buf, lzo_uint len)
 131 {
 132     lzo_uint32 crc;
 133 #undef table
 134 #if 1
 135 #  define table lzo_crc32_table
 136 #else
 137    const lzo_uint32 * table = lzo_crc32_table;
 138 #endif
 139
 140     if (buf == NULL)
 141         return 0;
 142
 143     crc = (c & LZO_UINT32_C(0xffffffff)) ^ LZO_UINT32_C(0xffffffff);
 144     if (len >= 16) do
 145     {
 146         LZO_DO16(buf,0);
 147         buf += 16;
 148         len -= 16;
 149     } while (len >= 16);
 150     if (len != 0) do
 151     {
 152         LZO_DO1(buf,0);
 153         buf += 1;
 154         len -= 1;
 155     } while (len > 0);
 156
 157     return crc ^ LZO_UINT32_C(0xffffffff);
 158 #undef table
 159 }
 160
 161 #undef LZO_DO1
 162 #undef LZO_DO2
 163 #undef LZO_DO4
 164 #undef LZO_DO8
 165 #undef LZO_DO16
 166
 167
 168 /*
 169 vi:ts=4:et
 170 */