/* vi: set sw=4 ts=4: */
/*
- * Mini uniq implementation for busybox
+ * uniq implementation for busybox
*
+ * Copyright (C) 2005 Manuel Novoa III <mjn3@codepoet.org>
*
- * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by John Beppu <beppu@lineo.com>
- * Rewritten by Matt Kraai <kraai@alumni.carnegiemellon.edu>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
-#include "busybox.h"
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
+/* BB_AUDIT SUSv3 compliant */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/uniq.html */
+
+//usage:#define uniq_trivial_usage
+//usage: "[-cdu][-f,s,w N] [INPUT [OUTPUT]]"
+//usage:#define uniq_full_usage "\n\n"
+//usage: "Discard duplicate lines\n"
+//usage: "\n -c Prefix lines by the number of occurrences"
+//usage: "\n -d Only print duplicate lines"
+//usage: "\n -u Only print unique lines"
+//usage: "\n -f N Skip first N fields"
+//usage: "\n -s N Skip first N chars (after any skipped fields)"
+//usage: "\n -w N Compare N characters in line"
+//usage:
+//usage:#define uniq_example_usage
+//usage: "$ echo -e \"a\\na\\nb\\nc\\nc\\na\" | sort | uniq\n"
+//usage: "a\n"
+//usage: "b\n"
+//usage: "c\n"
-int uniq_main(int argc, char **argv)
+#include "libbb.h"
+
+int uniq_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int uniq_main(int argc UNUSED_PARAM, char **argv)
{
- FILE *in = stdin, *out = stdout;
- char *lastline = NULL, *input;
+ const char *input_filename;
+ unsigned skip_fields, skip_chars, max_chars;
+ unsigned opt;
+ char *cur_line;
+ const char *cur_compare;
- /* parse argv[] */
- if ((argc > 1 && **(argv + 1) == '-') || argc > 3)
- usage(uniq_usage);
+ enum {
+ OPT_c = 0x1,
+ OPT_d = 0x2, /* print only dups */
+ OPT_u = 0x4, /* print only uniq */
+ OPT_f = 0x8,
+ OPT_s = 0x10,
+ OPT_w = 0x20,
+ };
- if (argv[1] != NULL) {
- in = xfopen(argv[1], "r");
- if (argv[2] != NULL)
- out = xfopen(argv[2], "w");
- }
+ skip_fields = skip_chars = 0;
+ max_chars = INT_MAX;
+
+ opt_complementary = "f+:s+:w+";
+ opt = getopt32(argv, "cduf:s:w:", &skip_fields, &skip_chars, &max_chars);
+ argv += optind;
- while ((input = get_line_from_file(in)) != NULL) {
- if (lastline == NULL || strcmp(input, lastline) != 0) {
- fputs(input, out);
- free(lastline);
- lastline = input;
+ input_filename = argv[0];
+ if (input_filename) {
+ const char *output;
+
+ if (input_filename[0] != '-' || input_filename[1]) {
+ close(STDIN_FILENO); /* == 0 */
+ xopen(input_filename, O_RDONLY); /* fd will be 0 */
+ }
+ output = argv[1];
+ if (output) {
+ if (argv[2])
+ bb_show_usage();
+ if (output[0] != '-' || output[1]) {
+ // Won't work with "uniq - FILE" and closed stdin:
+ //close(STDOUT_FILENO);
+ //xopen(output, O_WRONLY | O_CREAT | O_TRUNC);
+ xmove_fd(xopen(output, O_WRONLY | O_CREAT | O_TRUNC), STDOUT_FILENO);
+ }
}
}
- free(lastline);
- return EXIT_SUCCESS;
+ cur_compare = cur_line = NULL; /* prime the pump */
+
+ do {
+ unsigned i;
+ unsigned long dups;
+ char *old_line;
+ const char *old_compare;
+
+ old_line = cur_line;
+ old_compare = cur_compare;
+ dups = 0;
+
+ /* gnu uniq ignores newlines */
+ while ((cur_line = xmalloc_fgetline(stdin)) != NULL) {
+ cur_compare = cur_line;
+ for (i = skip_fields; i; i--) {
+ cur_compare = skip_whitespace(cur_compare);
+ cur_compare = skip_non_whitespace(cur_compare);
+ }
+ for (i = skip_chars; *cur_compare && i; i--) {
+ ++cur_compare;
+ }
+
+ if (!old_line || strncmp(old_compare, cur_compare, max_chars)) {
+ break;
+ }
+
+ free(cur_line);
+ ++dups; /* testing for overflow seems excessive */
+ }
+
+ if (old_line) {
+ if (!(opt & (OPT_d << !!dups))) { /* (if dups, opt & OPT_u) */
+ if (opt & OPT_c) {
+ /* %7lu matches GNU coreutils 6.9 */
+ printf("%7lu ", dups + 1);
+ }
+ printf("%s\n", old_line);
+ }
+ free(old_line);
+ }
+ } while (cur_line);
+
+ die_if_ferror(stdin, input_filename);
+
+ fflush_stdout_and_exit(EXIT_SUCCESS);
}
projects / platform / upstream / busybox.git / blobdiff