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// SPDX-License-Identifier: GPL-2.0-only
/* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */
/* Usage example:
$ ./crc32hash "Dual Speed"
*/
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
static unsigned int crc32(unsigned char const *p, unsigned int len)
{
int i;
unsigned int crc = 0;
while (len--) {
crc ^= *p++;
for (i = 0; i < 8; i++)
crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0);
}
return crc;
}
int main(int argc, char **argv) {
unsigned int result;
if (argc != 2) {
printf("no string passed as argument\n");
return -1;
}
result = crc32((unsigned char const *)argv[1], strlen(argv[1]));
printf("0x%x\n", result);
return 0;
}
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