blob: be550b5cdbecd75bbdd52bcef3f1c8ea622688da
| 1 | /* vi: set sw=4 ts=4: */ |
| 2 | /* |
| 3 | * uniq implementation for busybox |
| 4 | * |
| 5 | * Copyright (C) 2005 Manuel Novoa III <mjn3@codepoet.org> |
| 6 | * |
| 7 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| 8 | */ |
| 9 | //config:config UNIQ |
| 10 | //config: bool "uniq" |
| 11 | //config: default y |
| 12 | //config: help |
| 13 | //config: uniq is used to remove duplicate lines from a sorted file. |
| 14 | |
| 15 | //applet:IF_UNIQ(APPLET(uniq, BB_DIR_USR_BIN, BB_SUID_DROP)) |
| 16 | |
| 17 | //kbuild:lib-$(CONFIG_UNIQ) += uniq.o |
| 18 | |
| 19 | /* BB_AUDIT SUSv3 compliant */ |
| 20 | /* http://www.opengroup.org/onlinepubs/007904975/utilities/uniq.html */ |
| 21 | |
| 22 | //usage:#define uniq_trivial_usage |
| 23 | //usage: "[-cdu][-f,s,w N] [INPUT [OUTPUT]]" |
| 24 | //usage:#define uniq_full_usage "\n\n" |
| 25 | //usage: "Discard duplicate lines\n" |
| 26 | //usage: "\n -c Prefix lines by the number of occurrences" |
| 27 | //usage: "\n -d Only print duplicate lines" |
| 28 | //usage: "\n -u Only print unique lines" |
| 29 | //usage: "\n -f N Skip first N fields" |
| 30 | //usage: "\n -s N Skip first N chars (after any skipped fields)" |
| 31 | //usage: "\n -w N Compare N characters in line" |
| 32 | //usage: |
| 33 | //usage:#define uniq_example_usage |
| 34 | //usage: "$ echo -e \"a\\na\\nb\\nc\\nc\\na\" | sort | uniq\n" |
| 35 | //usage: "a\n" |
| 36 | //usage: "b\n" |
| 37 | //usage: "c\n" |
| 38 | |
| 39 | #include "libbb.h" |
| 40 | |
| 41 | int uniq_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| 42 | int uniq_main(int argc UNUSED_PARAM, char **argv) |
| 43 | { |
| 44 | const char *input_filename; |
| 45 | unsigned skip_fields, skip_chars, max_chars; |
| 46 | unsigned opt; |
| 47 | char *cur_line; |
| 48 | const char *cur_compare; |
| 49 | |
| 50 | enum { |
| 51 | OPT_c = 0x1, |
| 52 | OPT_d = 0x2, /* print only dups */ |
| 53 | OPT_u = 0x4, /* print only uniq */ |
| 54 | OPT_f = 0x8, |
| 55 | OPT_s = 0x10, |
| 56 | OPT_w = 0x20, |
| 57 | }; |
| 58 | |
| 59 | skip_fields = skip_chars = 0; |
| 60 | max_chars = INT_MAX; |
| 61 | |
| 62 | opt = getopt32(argv, "cduf:+s:+w:+", &skip_fields, &skip_chars, &max_chars); |
| 63 | argv += optind; |
| 64 | |
| 65 | input_filename = argv[0]; |
| 66 | if (input_filename) { |
| 67 | const char *output; |
| 68 | |
| 69 | if (input_filename[0] != '-' || input_filename[1]) { |
| 70 | close(STDIN_FILENO); /* == 0 */ |
| 71 | xopen(input_filename, O_RDONLY); /* fd will be 0 */ |
| 72 | } |
| 73 | output = argv[1]; |
| 74 | if (output) { |
| 75 | if (argv[2]) |
| 76 | bb_show_usage(); |
| 77 | if (output[0] != '-' || output[1]) { |
| 78 | // Won't work with "uniq - FILE" and closed stdin: |
| 79 | //close(STDOUT_FILENO); |
| 80 | //xopen(output, O_WRONLY | O_CREAT | O_TRUNC); |
| 81 | xmove_fd(xopen(output, O_WRONLY | O_CREAT | O_TRUNC), STDOUT_FILENO); |
| 82 | } |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | cur_compare = cur_line = NULL; /* prime the pump */ |
| 87 | |
| 88 | do { |
| 89 | unsigned i; |
| 90 | unsigned long dups; |
| 91 | char *old_line; |
| 92 | const char *old_compare; |
| 93 | |
| 94 | old_line = cur_line; |
| 95 | old_compare = cur_compare; |
| 96 | dups = 0; |
| 97 | |
| 98 | /* gnu uniq ignores newlines */ |
| 99 | while ((cur_line = xmalloc_fgetline(stdin)) != NULL) { |
| 100 | cur_compare = cur_line; |
| 101 | for (i = skip_fields; i; i--) { |
| 102 | cur_compare = skip_whitespace(cur_compare); |
| 103 | cur_compare = skip_non_whitespace(cur_compare); |
| 104 | } |
| 105 | for (i = skip_chars; *cur_compare && i; i--) { |
| 106 | ++cur_compare; |
| 107 | } |
| 108 | |
| 109 | if (!old_line || strncmp(old_compare, cur_compare, max_chars)) { |
| 110 | break; |
| 111 | } |
| 112 | |
| 113 | free(cur_line); |
| 114 | ++dups; /* testing for overflow seems excessive */ |
| 115 | } |
| 116 | |
| 117 | if (old_line) { |
| 118 | if (!(opt & (OPT_d << !!dups))) { /* (if dups, opt & OPT_u) */ |
| 119 | if (opt & OPT_c) { |
| 120 | /* %7lu matches GNU coreutils 6.9 */ |
| 121 | printf("%7lu ", dups + 1); |
| 122 | } |
| 123 | puts(old_line); |
| 124 | } |
| 125 | free(old_line); |
| 126 | } |
| 127 | } while (cur_line); |
| 128 | |
| 129 | die_if_ferror(stdin, input_filename); |
| 130 | |
| 131 | fflush_stdout_and_exit(EXIT_SUCCESS); |
| 132 | } |
| 133 |