source: branches/3.2/mindi-busybox/coreutils/sum.c @ 3232

Last change on this file since 3232 was 3232, checked in by bruno, 5 years ago
  • Update mindi-busybox to 1.21.1
File size: 2.8 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
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.
5 *
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>
9 *
10 * Written by Kayvan Aghaiepour and David MacKenzie
11 * Taken from coreutils and turned into a busybox applet by Mike Frysinger
12 *
13 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
14 */
15
16//usage:#define sum_trivial_usage
17//usage:       "[-rs] [FILE]..."
18//usage:#define sum_full_usage "\n\n"
19//usage:       "Checksum and count the blocks in a file\n"
20//usage:     "\n    -r  Use BSD sum algorithm (1K blocks)"
21//usage:     "\n    -s  Use System V sum algorithm (512byte blocks)"
22
23#include "libbb.h"
24
25enum { SUM_BSD, PRINT_NAME, SUM_SYSV };
26
27/* BSD: calculate and print the rotated checksum and the size in 1K blocks
28   The checksum varies depending on sizeof (int). */
29/* SYSV: calculate and print the checksum and the size in 512-byte blocks */
30/* Return 1 if successful.  */
31static unsigned sum_file(const char *file, unsigned type)
32{
33#define buf bb_common_bufsiz1
34    unsigned long long total_bytes = 0;
35    int fd, r;
36    /* The sum of all the input bytes, modulo (UINT_MAX + 1).  */
37    unsigned s = 0;
38
39    fd = open_or_warn_stdin(file);
40    if (fd == -1)
41        return 0;
42
43    while (1) {
44        size_t bytes_read = safe_read(fd, buf, BUFSIZ);
45
46        if ((ssize_t)bytes_read <= 0) {
47            r = (fd && close(fd) != 0);
48            if (!bytes_read && !r)
49                /* no error */
50                break;
51            bb_simple_perror_msg(file);
52            return 0;
53        }
54
55        total_bytes += bytes_read;
56        if (type >= SUM_SYSV) {
57            do s += buf[--bytes_read]; while (bytes_read);
58        } else {
59            r = 0;
60            do {
61                s = (s >> 1) + ((s & 1) << 15);
62                s += buf[r++];
63                s &= 0xffff; /* Keep it within bounds. */
64            } while (--bytes_read);
65        }
66    }
67
68    if (type < PRINT_NAME)
69        file = "";
70    if (type >= SUM_SYSV) {
71        r = (s & 0xffff) + ((s & 0xffffffff) >> 16);
72        s = (r & 0xffff) + (r >> 16);
73        printf("%d %llu %s\n", s, (total_bytes + 511) / 512, file);
74    } else
75        printf("%05d %5llu %s\n", s, (total_bytes + 1023) / 1024, file);
76    return 1;
77#undef buf
78}
79
80int sum_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
81int sum_main(int argc UNUSED_PARAM, char **argv)
82{
83    unsigned n;
84    unsigned type = SUM_BSD;
85
86    n = getopt32(argv, "sr");
87    argv += optind;
88    if (n & 1) type = SUM_SYSV;
89    /* give the bsd priority over sysv func */
90    if (n & 2) type = SUM_BSD;
91
92    if (!argv[0]) {
93        /* Do not print the name */
94        n = sum_file("-", type);
95    } else {
96        /* Need to print the name if either
97         * - more than one file given
98         * - doing sysv */
99        type += (argv[1] || type == SUM_SYSV);
100        n = 1;
101        do {
102            n &= sum_file(*argv, type);
103        } while (*++argv);
104    }
105    return !n;
106}
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