1 /* comm -- compare two sorted files line by line.
2 Copyright (C) 86, 90, 91, 1995-2001 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
18 /* Written by Richard Stallman and David MacKenzie. */
24 #include <sys/types.h>
27 #include "linebuffer.h"
29 #include "hard-locale.h"
32 /* The official name of this program (e.g., no `g' prefix). */
33 #define PROGRAM_NAME "comm"
35 #define AUTHORS N_ ("Richard Stallman and David MacKenzie")
37 /* Undefine, to avoid warning about redefinition on some systems. */
39 #define min(x, y) ((x) < (y) ? (x) : (y))
41 /* The name this program was run with. */
45 /* Nonzero if the LC_COLLATE locale is hard. */
46 static int hard_LC_COLLATE;
49 /* If nonzero, print lines that are found only in file 1. */
50 static int only_file_1;
52 /* If nonzero, print lines that are found only in file 2. */
53 static int only_file_2;
55 /* If nonzero, print lines that are found in both files. */
58 static struct option const long_options[] =
60 {GETOPT_HELP_OPTION_DECL},
61 {GETOPT_VERSION_OPTION_DECL},
71 fprintf (stderr, _("Try `%s --help' for more information.\n"),
76 Usage: %s [OPTION]... LEFT_FILE RIGHT_FILE\n\
80 Compare sorted files LEFT_FILE and RIGHT_FILE line by line.\n\
82 -1 suppress lines unique to left file\n\
83 -2 suppress lines unique to right file\n\
84 -3 suppress lines that appear in both files\n\
87 --help display this help and exit\n\
88 --version output version information and exit\n\
90 puts (_("\nReport bugs to <bug-textutils@gnu.org>."));
92 exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
95 /* Output the line in linebuffer LINE to stream STREAM
96 provided the switches say it should be output.
97 CLASS is 1 for a line found only in file 1,
98 2 for a line only in file 2, 3 for a line in both. */
101 writeline (const struct linebuffer *line, FILE *stream, int class)
113 /* Print a TAB if we are printing lines from file 1. */
121 /* Print a TAB if we are printing lines from file 1. */
124 /* Print a TAB if we are printing lines from file 2. */
130 fwrite (line->buffer, sizeof (char), line->length, stream);
133 /* Compare INFILES[0] and INFILES[1].
134 If either is "-", use the standard input for that file.
135 Assume that each input file is sorted;
136 merge them and output the result.
137 Return 0 if successful, 1 if any errors occur. */
140 compare_files (char **infiles)
142 /* For each file, we have one linebuffer in lb1. */
143 struct linebuffer lb1[2];
145 /* thisline[i] points to the linebuffer holding the next available line
146 in file i, or is NULL if there are no lines left in that file. */
147 struct linebuffer *thisline[2];
149 /* streams[i] holds the input stream for file i. */
154 /* Initialize the storage. */
155 for (i = 0; i < 2; i++)
157 initbuffer (&lb1[i]);
158 thisline[i] = &lb1[i];
159 streams[i] = (STREQ (infiles[i], "-") ? stdin : fopen (infiles[i], "r"));
162 error (0, errno, "%s", infiles[i]);
166 thisline[i] = readline (thisline[i], streams[i]);
169 while (thisline[0] || thisline[1])
173 /* Compare the next available lines of the two files. */
177 else if (!thisline[1])
183 order = memcoll (thisline[0]->buffer, thisline[0]->length - 1,
184 thisline[1]->buffer, thisline[1]->length - 1);
188 size_t len = min (thisline[0]->length, thisline[1]->length) - 1;
189 order = memcmp (thisline[0]->buffer, thisline[1]->buffer, len);
191 order = thisline[0]->length - thisline[1]->length;
195 /* Output the line that is lesser. */
197 writeline (thisline[1], stdout, 3);
199 writeline (thisline[1], stdout, 2);
201 writeline (thisline[0], stdout, 1);
203 /* Step the file the line came from.
204 If the files match, step both files. */
206 thisline[1] = readline (thisline[1], streams[1]);
208 thisline[0] = readline (thisline[0], streams[0]);
211 /* Free all storage and close all input streams. */
212 for (i = 0; i < 2; i++)
214 free (lb1[i].buffer);
215 if (ferror (streams[i]) || fclose (streams[i]) == EOF)
217 error (0, errno, "%s", infiles[i]);
225 main (int argc, char **argv)
229 program_name = argv[0];
230 setlocale (LC_ALL, "");
231 bindtextdomain (PACKAGE, LOCALEDIR);
232 textdomain (PACKAGE);
234 atexit (close_stdout);
237 hard_LC_COLLATE = hard_locale (LC_COLLATE);
244 while ((c = getopt_long (argc, argv, "123", long_options, NULL)) != -1)
262 case_GETOPT_HELP_CHAR;
264 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
270 if (optind + 2 != argc)
273 exit (compare_files (argv + optind) == 0
274 ? EXIT_SUCCESS : EXIT_FAILURE);