xref: /freebsd/usr.bin/comm/comm.c (revision 09e8dea79366f1e5b3a73e8a271b26e4b6bf2e6a)
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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static const char copyright[] =
39 "@(#) Copyright (c) 1989, 1993, 1994\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif
42 
43 #if 0
44 #ifndef lint
45 static char sccsid[] = "From: @(#)comm.c	8.4 (Berkeley) 5/4/95";
46 #endif
47 #endif
48 
49 #include <sys/cdefs.h>
50 __FBSDID("$FreeBSD$");
51 
52 #include <ctype.h>
53 #include <err.h>
54 #include <limits.h>
55 #include <locale.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 
61 #define	MAXLINELEN	(LINE_MAX + 1)
62 
63 const char *tabs[] = { "", "\t", "\t\t" };
64 
65 FILE   *file(char *);
66 void	show(FILE *, const char *, char *);
67 int     stricoll(char *, char *);
68 static void	usage(void);
69 
70 int
71 main(argc, argv)
72 	int argc;
73 	char *argv[];
74 {
75 	int comp, file1done = 0, file2done = 0, read1, read2;
76 	int ch, flag1, flag2, flag3, iflag;
77 	FILE *fp1, *fp2;
78 	const char *col1, *col2, *col3;
79 	char line1[MAXLINELEN], line2[MAXLINELEN];
80 	const char **p;
81 
82 	flag1 = flag2 = flag3 = 1;
83 	iflag = 0;
84 
85 	(void) setlocale(LC_ALL, "");
86 
87 	while ((ch = getopt(argc, argv, "123i")) != -1)
88 		switch(ch) {
89 		case '1':
90 			flag1 = 0;
91 			break;
92 		case '2':
93 			flag2 = 0;
94 			break;
95 		case '3':
96 			flag3 = 0;
97 			break;
98 		case 'i':
99 			iflag = 1;
100 			break;
101 		case '?':
102 		default:
103 			usage();
104 		}
105 	argc -= optind;
106 	argv += optind;
107 
108 	if (argc != 2)
109 		usage();
110 
111 	fp1 = file(argv[0]);
112 	fp2 = file(argv[1]);
113 
114 	/* for each column printed, add another tab offset */
115 	p = tabs;
116 	col1 = col2 = col3 = NULL;
117 	if (flag1)
118 		col1 = *p++;
119 	if (flag2)
120 		col2 = *p++;
121 	if (flag3)
122 		col3 = *p;
123 
124 	for (read1 = read2 = 1;;) {
125 		/* read next line, check for EOF */
126 		if (read1)
127 			file1done = !fgets(line1, MAXLINELEN, fp1);
128 		if (read2)
129 			file2done = !fgets(line2, MAXLINELEN, fp2);
130 
131 		/* if one file done, display the rest of the other file */
132 		if (file1done) {
133 			if (!file2done && col2)
134 				show(fp2, col2, line2);
135 			break;
136 		}
137 		if (file2done) {
138 			if (!file1done && col1)
139 				show(fp1, col1, line1);
140 			break;
141 		}
142 
143 		/* lines are the same */
144 		if(iflag)
145 			comp = stricoll(line1, line2);
146 		else
147 			comp = strcoll(line1, line2);
148 
149 		if (!comp) {
150 			read1 = read2 = 1;
151 			if (col3)
152 				(void)printf("%s%s", col3, line1);
153 			continue;
154 		}
155 
156 		/* lines are different */
157 		if (comp < 0) {
158 			read1 = 1;
159 			read2 = 0;
160 			if (col1)
161 				(void)printf("%s%s", col1, line1);
162 		} else {
163 			read1 = 0;
164 			read2 = 1;
165 			if (col2)
166 				(void)printf("%s%s", col2, line2);
167 		}
168 	}
169 	exit(0);
170 }
171 
172 void
173 show(fp, offset, buf)
174 	FILE *fp;
175 	const char *offset;
176 	char *buf;
177 {
178 
179 	do {
180 		(void)printf("%s%s", offset, buf);
181 	} while (fgets(buf, MAXLINELEN, fp));
182 }
183 
184 FILE *
185 file(name)
186 	char *name;
187 {
188 	FILE *fp;
189 
190 	if (!strcmp(name, "-"))
191 		return (stdin);
192 	if ((fp = fopen(name, "r")) == NULL) {
193 		err(1, "%s", name);
194 	}
195 	return (fp);
196 }
197 
198 static void
199 usage()
200 {
201 	(void)fprintf(stderr, "usage: comm [-123i] file1 file2\n");
202 	exit(1);
203 }
204 
205 int
206 stricoll(s1, s2)
207 	char *s1, *s2;
208 {
209 	char *p, line1[MAXLINELEN], line2[MAXLINELEN];
210 
211 	for (p = line1; *s1; s1++)
212 		*p++ = tolower((unsigned char)*s1);
213 	*p = '\0';
214 	for (p = line2; *s2; s2++)
215 		*p++ = tolower((unsigned char)*s2);
216 	*p = '\0';
217 	return strcoll(line1, line2);
218 }
219