54 lines
1.2 KiB
C
54 lines
1.2 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* cksum - calculate the CRC32 checksum of a file
|
|
*
|
|
* Copyright (C) 2006 by Rob Sullivan, with ideas from code by Walter Harms
|
|
*
|
|
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */
|
|
|
|
#include "busybox.h"
|
|
|
|
int cksum_main(int argc, char **argv);
|
|
int cksum_main(int argc, char **argv)
|
|
{
|
|
uint32_t *crc32_table = crc32_filltable(NULL, 1);
|
|
|
|
FILE *fp;
|
|
uint32_t crc;
|
|
long length, filesize;
|
|
int bytes_read;
|
|
char *cp;
|
|
|
|
int inp_stdin = (argc == optind) ? 1 : 0;
|
|
|
|
do {
|
|
fp = fopen_or_warn_stdin((inp_stdin) ? bb_msg_standard_input : *++argv);
|
|
|
|
crc = 0;
|
|
length = 0;
|
|
|
|
while ((bytes_read = fread(bb_common_bufsiz1, 1, BUFSIZ, fp)) > 0) {
|
|
cp = bb_common_bufsiz1;
|
|
length += bytes_read;
|
|
while (bytes_read--)
|
|
crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ (*cp++)) & 0xffL];
|
|
}
|
|
|
|
filesize = length;
|
|
|
|
for (; length; length >>= 8)
|
|
crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ length) & 0xffL];
|
|
crc ^= 0xffffffffL;
|
|
|
|
if (inp_stdin) {
|
|
printf("%" PRIu32 " %li\n", crc, filesize);
|
|
break;
|
|
}
|
|
|
|
printf("%" PRIu32 " %li %s\n", crc, filesize, *argv);
|
|
fclose(fp);
|
|
} while (*(argv + 1));
|
|
|
|
fflush_stdout_and_exit(EXIT_SUCCESS);
|
|
}
|