1 /* vi: set sw=4 ts=4: */
3 * sum -- checksum and count the blocks in a file
4 * Like BSD sum or SysV sum -r, except like SysV sum if -s option is given.
6 * Copyright (C) 86, 89, 91, 1995-2002, 2004 Free Software Foundation, Inc.
7 * Copyright (C) 2005 by Erik Andersen <andersen@codepoet.org>
8 * Copyright (C) 2005 by Mike Frysinger <vapier@gentoo.org>
10 * Written by Kayvan Aghaiepour and David MacKenzie
11 * Taken from coreutils and turned into a busybox applet by Mike Frysinger
13 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
18 enum { SUM_BSD, PRINT_NAME, SUM_SYSV };
20 /* BSD: calculate and print the rotated checksum and the size in 1K blocks
21 The checksum varies depending on sizeof (int). */
22 /* SYSV: calculate and print the checksum and the size in 512-byte blocks */
23 /* Return 1 if successful. */
24 static unsigned sum_file(const char *file, const unsigned type)
26 #define buf bb_common_bufsiz1
27 uintmax_t total_bytes = 0;
30 /* The sum of all the input bytes, modulo (UINT_MAX + 1). */
33 if (NOT_LONE_DASH(file)) {
34 fd = open(file, O_RDONLY);
40 size_t bytes_read = safe_read(fd, buf, BUFSIZ);
42 if ((ssize_t)bytes_read <= 0) {
43 r = (fd && close(fd) != 0);
44 if (!bytes_read && !r)
52 total_bytes += bytes_read;
53 if (type >= SUM_SYSV) {
54 do s += buf[--bytes_read]; while (bytes_read);
58 s = (s >> 1) + ((s & 1) << 15);
60 s &= 0xffff; /* Keep it within bounds. */
61 } while (--bytes_read);
65 if (type < PRINT_NAME)
67 if (type >= SUM_SYSV) {
68 r = (s & 0xffff) + ((s & 0xffffffff) >> 16);
69 s = (r & 0xffff) + (r >> 16);
70 printf("%d %ju %s\n", s, (total_bytes+511)/512, file);
72 printf("%05d %5ju %s\n", s, (total_bytes+1023)/1024, file);
77 int sum_main(int argc, char **argv);
78 int sum_main(int argc, char **argv)
81 unsigned type = SUM_BSD;
83 n = getopt32(argv, "sr");
84 if (n & 1) type = SUM_SYSV;
85 /* give the bsd priority over sysv func */
86 if (n & 2) type = SUM_BSD;
89 /* Do not print the name */
90 n = sum_file("-", type);
92 /* Need to print the name if either
93 - more than one file given
95 type += argc - 1 > optind || type == SUM_SYSV;
96 for (n = 1; optind < argc; optind++)
97 n &= sum_file(argv[optind], type);