Documentation/pcmcia/crc32hash.c

   1 /* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */
   2 /* Usage example:
   3 $ ./crc32hash "Dual Speed"
   4 */
   5
   6 #include <string.h>
   7 #include <stdio.h>
   8 #include <ctype.h>
   9 #include <stdlib.h>
  10
  11 unsigned int crc32(unsigned char const *p, unsigned int len)
  12 {
  13         int i;
  14         unsigned int crc = 0;
  15         while (len--) {
  16                 crc ^= *p++;
  17                 for (i = 0; i < 8; i++)
  18                         crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0);
  19         }
  20         return crc;
  21 }
  22
  23 int main(int argc, char **argv) {
  24         unsigned int result;
  25         if (argc != 2) {
  26                 printf("no string passed as argument\n");
  27                 return -1;
  28         }
  29         result = crc32((unsigned char const *)argv[1], strlen(argv[1]));
  30         printf("0x%x\n", result);
  31         return 0;
  32 }