Bump to version 1.22.1
[platform/upstream/busybox.git] / coreutils / uniq.c
index c0229ae..9208d34 100644 (file)
 /* 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 */
 
-static int print_count;
-static int print_uniq = 1;
-static int print_duplicates = 1;
+//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"
 
-static void print_line(char *line, int count, FILE *fp)
-{
-       if ((print_duplicates && count > 1) || (print_uniq && count == 1)) {
-               if (print_count)
-                       fprintf(fp, "%7d\t%s", count, line);
-               else
-                       fputs(line, fp);
-       }
-}
+#include "libbb.h"
 
-int uniq_main(int argc, char **argv)
+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;
-       int opt, count = 0;
-
-       /* parse argv[] */
-       while ((opt = getopt(argc, argv, "cdu")) > 0) {
-               switch (opt) {
-                       case 'c':
-                               print_count = 1;
-                               break;
-                       case 'd':
-                               print_duplicates = 1;
-                               print_uniq = 0;
-                               break;
-                       case 'u':
-                               print_duplicates = 0;
-                               print_uniq = 1;
-                               break;
+       const char *input_filename;
+       unsigned skip_fields, skip_chars, max_chars;
+       unsigned opt;
+       char *cur_line;
+       const char *cur_compare;
+
+       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,
+       };
+
+       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;
+
+       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);
+                       }
                }
        }
 
-       if (argv[optind] != NULL) {
-               in = xfopen(argv[optind], "r");
-               if (argv[optind+1] != NULL)
-                       out = xfopen(argv[optind+1], "w");
-       }
+       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;
+                       }
 
-       while ((input = get_line_from_file(in)) != NULL) {
-               if (lastline == NULL || strcmp(input, lastline) != 0) {
-                       print_line(lastline, count, out);
-                       free(lastline);
-                       lastline = input;
-                       count = 0;
+                       if (!old_line || strncmp(old_compare, cur_compare, max_chars)) {
+                               break;
+                       }
+
+                       free(cur_line);
+                       ++dups;  /* testing for overflow seems excessive */
                }
-               count++;
-       }
-       print_line(lastline, count, out);
-       free(lastline);
 
-       return EXIT_SUCCESS;
+               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);
 }