Randy Dunlap | d29693b | 2006-05-21 20:57:42 -0700 | [diff] [blame] | 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 | |
Ladinu Chandrasinghe | b7ed698 | 2009-09-22 16:43:42 -0700 | [diff] [blame] | 11 | static unsigned int crc32(unsigned char const *p, unsigned int len) |
Randy Dunlap | d29693b | 2006-05-21 20:57:42 -0700 | [diff] [blame] | 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 | } |
Randy Dunlap | ffab10e | 2008-08-12 15:09:08 -0700 | [diff] [blame] | 29 | result = crc32((unsigned char const *)argv[1], strlen(argv[1])); |
Randy Dunlap | d29693b | 2006-05-21 20:57:42 -0700 | [diff] [blame] | 30 | printf("0x%x\n", result); |
| 31 | return 0; |
| 32 | } |