xref: /freebsd/usr.bin/comm/comm.c (revision c11e094d96120a2e0e726ed9705ae0ec08db49b6)
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 '-':
90 			--optind;
91 			goto done;
92 		case '1':
93 			flag1 = 0;
94 			break;
95 		case '2':
96 			flag2 = 0;
97 			break;
98 		case '3':
99 			flag3 = 0;
100 			break;
101 		case 'i':
102 			iflag = 1;
103 			break;
104 		case '?':
105 		default:
106 			usage();
107 		}
108 done:	argc -= optind;
109 	argv += optind;
110 
111 	if (argc != 2)
112 		usage();
113 
114 	fp1 = file(argv[0]);
115 	fp2 = file(argv[1]);
116 
117 	/* for each column printed, add another tab offset */
118 	p = tabs;
119 	col1 = col2 = col3 = NULL;
120 	if (flag1)
121 		col1 = *p++;
122 	if (flag2)
123 		col2 = *p++;
124 	if (flag3)
125 		col3 = *p;
126 
127 	for (read1 = read2 = 1;;) {
128 		/* read next line, check for EOF */
129 		if (read1)
130 			file1done = !fgets(line1, MAXLINELEN, fp1);
131 		if (read2)
132 			file2done = !fgets(line2, MAXLINELEN, fp2);
133 
134 		/* if one file done, display the rest of the other file */
135 		if (file1done) {
136 			if (!file2done && col2)
137 				show(fp2, col2, line2);
138 			break;
139 		}
140 		if (file2done) {
141 			if (!file1done && col1)
142 				show(fp1, col1, line1);
143 			break;
144 		}
145 
146 		/* lines are the same */
147 		if(iflag)
148 			comp = stricoll(line1, line2);
149 		else
150 			comp = strcoll(line1, line2);
151 
152 		if (!comp) {
153 			read1 = read2 = 1;
154 			if (col3)
155 				(void)printf("%s%s", col3, line1);
156 			continue;
157 		}
158 
159 		/* lines are different */
160 		if (comp < 0) {
161 			read1 = 1;
162 			read2 = 0;
163 			if (col1)
164 				(void)printf("%s%s", col1, line1);
165 		} else {
166 			read1 = 0;
167 			read2 = 1;
168 			if (col2)
169 				(void)printf("%s%s", col2, line2);
170 		}
171 	}
172 	exit(0);
173 }
174 
175 void
176 show(fp, offset, buf)
177 	FILE *fp;
178 	const char *offset;
179 	char *buf;
180 {
181 
182 	do {
183 		(void)printf("%s%s", offset, buf);
184 	} while (fgets(buf, MAXLINELEN, fp));
185 }
186 
187 FILE *
188 file(name)
189 	char *name;
190 {
191 	FILE *fp;
192 
193 	if (!strcmp(name, "-"))
194 		return (stdin);
195 	if ((fp = fopen(name, "r")) == NULL) {
196 		err(1, "%s", name);
197 	}
198 	return (fp);
199 }
200 
201 static void
202 usage()
203 {
204 	(void)fprintf(stderr, "usage: comm [-123i] file1 file2\n");
205 	exit(1);
206 }
207 
208 int
209 stricoll(s1, s2)
210 	char *s1, *s2;
211 {
212 	char *p, line1[MAXLINELEN], line2[MAXLINELEN];
213 
214 	for (p = line1; *s1; s1++)
215 		*p++ = tolower((unsigned char)*s1);
216 	*p = '\0';
217 	for (p = line2; *s2; s2++)
218 		*p++ = tolower((unsigned char)*s2);
219 	*p = '\0';
220 	return strcoll(line1, line2);
221 }
222