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C/C++ Source or Header  |  1991-06-07  |  6KB  |  144 lines
  1. #include <stddef.h>
  2. #include <ctype.h>
  3. #include <string.h>
  4. #include <memory.h>
  5. #include <time.h>
  6. #include "nofast.h"
  7.  
  8.  long _fastcall crc32blk (char *str,int blklen);
  9.  long _fastcall crc32str(char *str,int casesensitive);
  10.  
  11.  static long cr3tab[] = {             /* CRC polynomial 0xEDB88320 */
  12.  
  13.    0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
  14.    0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
  15.    0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
  16.    0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
  17.    0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
  18.    0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
  19.    0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
  20.    0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
  21.    0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
  22.    0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
  23.    0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
  24.    0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
  25.    0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
  26.    0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
  27.    0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
  28.    0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
  29.    0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
  30.    0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
  31.    0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
  32.    0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
  33.    0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
  34.    0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
  35.    0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
  36.    0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
  37.    0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
  38.    0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
  39.    0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
  40.    0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
  41.    0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
  42.    0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
  43.    0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
  44.    0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
  45.    0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
  46.    0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
  47.    0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
  48.    0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
  49.    0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
  50.    0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
  51.    0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
  52.    0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
  53.    0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
  54.    0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
  55.    0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
  56.    0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
  57.    0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
  58.    0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
  59.    0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
  60.    0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
  61.    0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
  62.    0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
  63.    0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
  64.    0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
  65.    0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
  66.    0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
  67.    0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
  68.    0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
  69.    0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
  70.    0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
  71.    0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
  72.    0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
  73.    0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
  74.    0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
  75.    0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
  76.    0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
  77.  };
  78.  
  79.  
  80.  
  81.  
  82. /*-------------------------------------------------------------------------*/
  83. /* Calculate CRC-32 of variable length string                              */
  84. /*-------------------------------------------------------------------------*/
  85. /*                                                                         */
  86. /*  Usage: Passed pointer to ASCIIZ string to take CRC-32 of, as 'str'.    */
  87. /*                                                                         */
  88. /*   Rets: (long) CRC-32 value of passed string.                           */
  89. /*                                                                         */
  90. /*  Notes: The function treats the passed string as UPPER CASE so          */
  91. /*         it is insensitive to case.                                      */
  92. /*                                                                         */
  93. /*-------------------------------------------------------------------------*/
  94.  
  95. long _fastcall crc32str (char *str,int casesensitive) {
  96.  
  97.     long crc = 0L;
  98.  
  99.  
  100.     if(casesensitive) {
  101.         while(*str) {
  102.             crc =
  103.               cr3tab[((int)crc ^ *str) & 0xff] ^ ((crc >> 8) & 0x00FFFFFF);
  104.             str++;
  105.         }
  106.     }
  107.     else {
  108.         while(*str) {
  109.             crc =
  110.               cr3tab[((int)crc ^ toupper(*str)) & 0xff] ^ ((crc >> 8) & 0x00FFFFFF);
  111.             str++;
  112.         }
  113.     }
  114.  
  115.     return crc;
  116. }
  117.  
  118.  
  119.  
  120. /*-------------------------------------------------------------------------*/
  121. /* Calculate CRC-32 of memory block                                        */
  122. /*-------------------------------------------------------------------------*/
  123. /*                                                                         */
  124. /*  Usage: Passed pointer to memory block (cast to char *) as 'str' and    */
  125. /*         block length as int 'blklen'.                                   */
  126. /*                                                                         */
  127. /*   Rets: (long) CRC-32 value of passed block.                            */
  128. /*                                                                         */
  129. /*-------------------------------------------------------------------------*/
  130.  
  131. long _fastcall crc32blk (char *str,int blklen) {
  132.  
  133.    long crc = 0L;
  134.  
  135.  
  136.    while(blklen--) {
  137.       crc =
  138.        cr3tab[((int)crc ^ *str) & 0xff] ^ ((crc >> 8) & 0x00FFFFFF);
  139.       str++;
  140.    }
  141.  
  142.    return crc;
  143. }
  144.