blob: c55293dc9673af11b3b12fb37e67989c8c2b7c27
| 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 | //config:config SUM |
| 16 | //config: bool "sum" |
| 17 | //config: default y |
| 18 | //config: help |
| 19 | //config: checksum and count the blocks in a file |
| 20 | |
| 21 | //applet:IF_SUM(APPLET(sum, BB_DIR_USR_BIN, BB_SUID_DROP)) |
| 22 | |
| 23 | //kbuild:lib-$(CONFIG_SUM) += sum.o |
| 24 | |
| 25 | //usage:#define sum_trivial_usage |
| 26 | //usage: "[-rs] [FILE]..." |
| 27 | //usage:#define sum_full_usage "\n\n" |
| 28 | //usage: "Checksum and count the blocks in a file\n" |
| 29 | //usage: "\n -r Use BSD sum algorithm (1K blocks)" |
| 30 | //usage: "\n -s Use System V sum algorithm (512byte blocks)" |
| 31 | |
| 32 | #include "libbb.h" |
| 33 | #include "common_bufsiz.h" |
| 34 | |
| 35 | enum { SUM_BSD, PRINT_NAME, SUM_SYSV }; |
| 36 | |
| 37 | /* BSD: calculate and print the rotated checksum and the size in 1K blocks |
| 38 | The checksum varies depending on sizeof (int). */ |
| 39 | /* SYSV: calculate and print the checksum and the size in 512-byte blocks */ |
| 40 | /* Return 1 if successful. */ |
| 41 | static unsigned sum_file(const char *file, unsigned type) |
| 42 | { |
| 43 | unsigned long long total_bytes = 0; |
| 44 | int fd, r; |
| 45 | /* The sum of all the input bytes, modulo (UINT_MAX + 1). */ |
| 46 | unsigned s = 0; |
| 47 | |
| 48 | #define buf bb_common_bufsiz1 |
| 49 | setup_common_bufsiz(); |
| 50 | |
| 51 | fd = open_or_warn_stdin(file); |
| 52 | if (fd == -1) |
| 53 | return 0; |
| 54 | |
| 55 | while (1) { |
| 56 | size_t bytes_read = safe_read(fd, buf, COMMON_BUFSIZE); |
| 57 | |
| 58 | if ((ssize_t)bytes_read <= 0) { |
| 59 | r = (fd && close(fd) != 0); |
| 60 | if (!bytes_read && !r) |
| 61 | /* no error */ |
| 62 | break; |
| 63 | bb_simple_perror_msg(file); |
| 64 | return 0; |
| 65 | } |
| 66 | |
| 67 | total_bytes += bytes_read; |
| 68 | if (type >= SUM_SYSV) { |
| 69 | do s += buf[--bytes_read]; while (bytes_read); |
| 70 | } else { |
| 71 | r = 0; |
| 72 | do { |
| 73 | s = (s >> 1) + ((s & 1) << 15); |
| 74 | s += buf[r++]; |
| 75 | s &= 0xffff; /* Keep it within bounds. */ |
| 76 | } while (--bytes_read); |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | if (type < PRINT_NAME) |
| 81 | file = ""; |
| 82 | if (type >= SUM_SYSV) { |
| 83 | r = (s & 0xffff) + ((s & 0xffffffff) >> 16); |
| 84 | s = (r & 0xffff) + (r >> 16); |
| 85 | printf("%u %llu %s\n", s, (total_bytes + 511) / 512, file); |
| 86 | } else |
| 87 | printf("%05u %5llu %s\n", s, (total_bytes + 1023) / 1024, file); |
| 88 | return 1; |
| 89 | #undef buf |
| 90 | } |
| 91 | |
| 92 | int sum_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| 93 | int sum_main(int argc UNUSED_PARAM, char **argv) |
| 94 | { |
| 95 | unsigned n; |
| 96 | unsigned type = SUM_BSD; |
| 97 | |
| 98 | n = getopt32(argv, "sr"); |
| 99 | argv += optind; |
| 100 | if (n & 1) type = SUM_SYSV; |
| 101 | /* give the bsd priority over sysv func */ |
| 102 | if (n & 2) type = SUM_BSD; |
| 103 | |
| 104 | if (!argv[0]) { |
| 105 | /* Do not print the name */ |
| 106 | n = sum_file("-", type); |
| 107 | } else { |
| 108 | /* Need to print the name if either |
| 109 | * - more than one file given |
| 110 | * - doing sysv */ |
| 111 | type += (argv[1] || type == SUM_SYSV); |
| 112 | n = 1; |
| 113 | do { |
| 114 | n &= sum_file(*argv, type); |
| 115 | } while (*++argv); |
| 116 | } |
| 117 | return !n; |
| 118 | } |
| 119 |