1/*
2 * Copyright (c) 1989, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Case Larsen.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#ifndef lint
34static const char copyright[] =
35"@(#) Copyright (c) 1989, 1993, 1994\n\
36	The Regents of the University of California.  All rights reserved.\n";
37#endif
38
39#if 0
40#ifndef lint
41static char sccsid[] = "From: @(#)comm.c	8.4 (Berkeley) 5/4/95";
42#endif
43#endif
44
45#include <sys/cdefs.h>
46__FBSDID("$FreeBSD$");
47
48#include <err.h>
49#include <limits.h>
50#include <locale.h>
51#include <stdint.h>
52#define _WITH_GETLINE
53#include <stdio.h>
54#include <stdlib.h>
55#include <string.h>
56#include <unistd.h>
57#include <wchar.h>
58#include <wctype.h>
59
60static int iflag;
61static const char *tabs[] = { "", "\t", "\t\t" };
62
63static FILE	*file(const char *);
64static wchar_t	*convert(const char *);
65static void	show(FILE *, const char *, const char *, char **, size_t *);
66static void	usage(void);
67
68int
69main(int argc, char *argv[])
70{
71	int comp, read1, read2;
72	int ch, flag1, flag2, flag3;
73	FILE *fp1, *fp2;
74	const char *col1, *col2, *col3;
75	size_t line1len, line2len;
76	char *line1, *line2;
77	ssize_t n1, n2;
78	wchar_t *tline1, *tline2;
79	const char **p;
80
81	(void) setlocale(LC_ALL, "");
82
83	flag1 = flag2 = flag3 = 1;
84
85	while ((ch = getopt(argc, argv, "123i")) != -1)
86		switch(ch) {
87		case '1':
88			flag1 = 0;
89			break;
90		case '2':
91			flag2 = 0;
92			break;
93		case '3':
94			flag3 = 0;
95			break;
96		case 'i':
97			iflag = 1;
98			break;
99		case '?':
100		default:
101			usage();
102		}
103	argc -= optind;
104	argv += optind;
105
106	if (argc != 2)
107		usage();
108
109	fp1 = file(argv[0]);
110	fp2 = file(argv[1]);
111
112	/* for each column printed, add another tab offset */
113	p = tabs;
114	col1 = col2 = col3 = NULL;
115	if (flag1)
116		col1 = *p++;
117	if (flag2)
118		col2 = *p++;
119	if (flag3)
120		col3 = *p;
121
122	line1len = line2len = 0;
123	line1 = line2 = NULL;
124	n1 = n2 = -1;
125
126	for (read1 = read2 = 1;;) {
127		/* read next line, check for EOF */
128		if (read1) {
129			n1 = getline(&line1, &line1len, fp1);
130			if (n1 < 0 && ferror(fp1))
131				err(1, "%s", argv[0]);
132			if (n1 > 0 && line1[n1 - 1] == '\n')
133				line1[n1 - 1] = '\0';
134
135		}
136		if (read2) {
137			n2 = getline(&line2, &line2len, fp2);
138			if (n2 < 0 && ferror(fp2))
139				err(1, "%s", argv[1]);
140			if (n2 > 0 && line2[n2 - 1] == '\n')
141				line2[n2 - 1] = '\0';
142		}
143
144		/* if one file done, display the rest of the other file */
145		if (n1 < 0) {
146			if (n2 >= 0 && col2 != NULL)
147				show(fp2, argv[1], col2, &line2, &line2len);
148			break;
149		}
150		if (n2 < 0) {
151			if (n1 >= 0 && col1 != NULL)
152				show(fp1, argv[0], col1, &line1, &line1len);
153			break;
154		}
155
156		tline2 = NULL;
157		if ((tline1 = convert(line1)) != NULL)
158			tline2 = convert(line2);
159		if (tline1 == NULL || tline2 == NULL)
160			comp = strcmp(line1, line2);
161		else
162			comp = wcscoll(tline1, tline2);
163		if (tline1 != NULL)
164			free(tline1);
165		if (tline2 != NULL)
166			free(tline2);
167
168		/* lines are the same */
169		if (!comp) {
170			read1 = read2 = 1;
171			if (col3 != NULL)
172				(void)printf("%s%s\n", col3, line1);
173			continue;
174		}
175
176		/* lines are different */
177		if (comp < 0) {
178			read1 = 1;
179			read2 = 0;
180			if (col1 != NULL)
181				(void)printf("%s%s\n", col1, line1);
182		} else {
183			read1 = 0;
184			read2 = 1;
185			if (col2 != NULL)
186				(void)printf("%s%s\n", col2, line2);
187		}
188	}
189	exit(0);
190}
191
192static wchar_t *
193convert(const char *str)
194{
195	size_t n;
196	wchar_t *buf, *p;
197
198	if ((n = mbstowcs(NULL, str, 0)) == (size_t)-1)
199		return (NULL);
200	if (SIZE_MAX / sizeof(*buf) < n + 1)
201		errx(1, "conversion buffer length overflow");
202	if ((buf = malloc((n + 1) * sizeof(*buf))) == NULL)
203		err(1, "malloc");
204	if (mbstowcs(buf, str, n + 1) != n)
205		errx(1, "internal mbstowcs() error");
206
207	if (iflag) {
208		for (p = buf; *p != L'\0'; p++)
209			*p = towlower(*p);
210	}
211
212	return (buf);
213}
214
215static void
216show(FILE *fp, const char *fn, const char *offset, char **bufp, size_t *buflenp)
217{
218	ssize_t n;
219
220	do {
221		(void)printf("%s%s\n", offset, *bufp);
222		if ((n = getline(bufp, buflenp, fp)) < 0)
223			break;
224		if (n > 0 && (*bufp)[n - 1] == '\n')
225			(*bufp)[n - 1] = '\0';
226	} while (1);
227	if (ferror(fp))
228		err(1, "%s", fn);
229}
230
231static FILE *
232file(const char *name)
233{
234	FILE *fp;
235
236	if (!strcmp(name, "-"))
237		return (stdin);
238	if ((fp = fopen(name, "r")) == NULL) {
239		err(1, "%s", name);
240	}
241	return (fp);
242}
243
244static void
245usage(void)
246{
247	(void)fprintf(stderr, "usage: comm [-123i] file1 file2\n");
248	exit(1);
249}
250