1// SPDX-License-Identifier: GPL-2.0-only
 2/* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */
 3/* Usage example:
 4$ ./crc32hash "Dual Speed"
 5*/
 6
 7#include <string.h>
 8#include <stdio.h>
 9#include <ctype.h>
10#include <stdlib.h>
11
12static unsigned int crc32(unsigned char const *p, unsigned int len)
13{
14	int i;
15	unsigned int crc = 0;
16	while (len--) {
17		crc ^= *p++;
18		for (i = 0; i < 8; i++)
19			crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0);
20	}
21	return crc;
22}
23
24int main(int argc, char **argv) {
25	unsigned int result;
26	if (argc != 2) {
27		printf("no string passed as argument\n");
28		return -1;
29	}
30	result = crc32((unsigned char const *)argv[1], strlen(argv[1]));
31	printf("0x%x\n", result);
32	return 0;
33}

 1// SPDX-License-Identifier: GPL-2.0-only
 2/* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */
 3/* Usage example:
 4$ ./crc32hash "Dual Speed"
 5*/
 6
 7#include <string.h>
 8#include <stdio.h>
 9#include <ctype.h>
10#include <stdlib.h>
11
12static unsigned int crc32(unsigned char const *p, unsigned int len)
13{
14	int i;
15	unsigned int crc = 0;
16	while (len--) {
17		crc ^= *p++;
18		for (i = 0; i < 8; i++)
19			crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0);
20	}
21	return crc;
22}
23
24int main(int argc, char **argv) {
25	unsigned int result;
26	if (argc != 2) {
27		printf("no string passed as argument\n");
28		return -1;
29	}
30	result = crc32((unsigned char const *)argv[1], strlen(argv[1]));
31	printf("0x%x\n", result);
32	return 0;
33}