1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only 2*4882a593Smuzhiyun /* crc32hash.c - derived from linux/lib/crc32.c, GNU GPL v2 */ 3*4882a593Smuzhiyun /* Usage example: 4*4882a593Smuzhiyun $ ./crc32hash "Dual Speed" 5*4882a593Smuzhiyun */ 6*4882a593Smuzhiyun 7*4882a593Smuzhiyun #include <string.h> 8*4882a593Smuzhiyun #include <stdio.h> 9*4882a593Smuzhiyun #include <ctype.h> 10*4882a593Smuzhiyun #include <stdlib.h> 11*4882a593Smuzhiyun crc32(unsigned char const * p,unsigned int len)12*4882a593Smuzhiyunstatic unsigned int crc32(unsigned char const *p, unsigned int len) 13*4882a593Smuzhiyun { 14*4882a593Smuzhiyun int i; 15*4882a593Smuzhiyun unsigned int crc = 0; 16*4882a593Smuzhiyun while (len--) { 17*4882a593Smuzhiyun crc ^= *p++; 18*4882a593Smuzhiyun for (i = 0; i < 8; i++) 19*4882a593Smuzhiyun crc = (crc >> 1) ^ ((crc & 1) ? 0xedb88320 : 0); 20*4882a593Smuzhiyun } 21*4882a593Smuzhiyun return crc; 22*4882a593Smuzhiyun } 23*4882a593Smuzhiyun main(int argc,char ** argv)24*4882a593Smuzhiyunint main(int argc, char **argv) { 25*4882a593Smuzhiyun unsigned int result; 26*4882a593Smuzhiyun if (argc != 2) { 27*4882a593Smuzhiyun printf("no string passed as argument\n"); 28*4882a593Smuzhiyun return -1; 29*4882a593Smuzhiyun } 30*4882a593Smuzhiyun result = crc32((unsigned char const *)argv[1], strlen(argv[1])); 31*4882a593Smuzhiyun printf("0x%x\n", result); 32*4882a593Smuzhiyun return 0; 33*4882a593Smuzhiyun } 34