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/* vi: set sw=4 ts=4: */
/*
* sum -- checksum and count the blocks in a file
* Like BSD sum or SysV sum -r, except like SysV sum if -s option is given.
*
* Copyright (C) 86, 89, 91, 1995-2002, 2004 Free Software Foundation, Inc.
* Copyright (C) 2005 by Erik Andersen <andersen@codepoet.org>
* Copyright (C) 2005 by Mike Frysinger <vapier@gentoo.org>
*
* Written by Kayvan Aghaiepour and David MacKenzie
* Taken from coreutils and turned into a busybox applet by Mike Frysinger
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
#include "busybox.h"
enum { sysv_sum, bsd_sum };
/* BSD: calculate and print the rotated checksum and the size in 1K blocks
The checksum varies depending on sizeof (int). */
/* SYSV: calculate and print the checksum and the size in 512-byte blocks */
/* Return 1 if successful. */
static int sum_file(const char *file, int type, int print_name)
{
#define buf bb_common_bufsiz1
int r, fd;
uintmax_t total_bytes = 0;
/* The sum of all the input bytes, modulo (UINT_MAX + 1). */
unsigned s = 0;
fd = 0;
if (NOT_LONE_DASH(file)) {
fd = open(file, O_RDONLY);
if (fd == -1)
goto ret_bad;
}
while (1) {
size_t bytes_read = safe_read(fd, buf, BUFSIZ);
if ((ssize_t)bytes_read <= 0) {
r = (fd && close(fd) != 0);
if (!bytes_read && !r)
/* no error */
break;
ret_bad:
bb_perror_msg(file);
return 0;
}
total_bytes += bytes_read;
if (type == sysv_sum) {
do s += buf[--bytes_read]; while (bytes_read);
} else {
r = 0;
do {
s = (s >> 1) + ((s & 1) << 15);
s += buf[r++];
s &= 0xffff; /* Keep it within bounds. */
} while (--bytes_read);
}
}
if (!print_name) file = "";
if (type == sysv_sum) {
r = (s & 0xffff) + ((s & 0xffffffff) >> 16);
s = (r & 0xffff) + (r >> 16);
printf("%d %ju %s\n", s, (total_bytes+511)/512, file);
} else
printf("%05d %5ju %s\n", s, (total_bytes+1023)/1024, file);
return 1;
#undef buf
}
int sum_main(int argc, char **argv)
{
int n;
int type = bsd_sum;
n = getopt32(argc, argv, "sr");
if (n & 1) type = sysv_sum;
/* give the bsd priority over sysv func */
if (n & 2) type = bsd_sum;
if (argc == optind)
n = sum_file("-", type, 0);
else
for (n = 1; optind < argc; optind++)
n &= sum_file(argv[optind], type, 1);
return !n;
}
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