xref: /dragonfly/usr.bin/comm/comm.c (revision af79c6e5)
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  * @(#) Copyright (c) 1989, 1993, 1994 The Regents of the University of California.  All rights reserved.
37  * @(#)comm.c	8.4 (Berkeley) 5/4/95
38  * $FreeBSD: src/usr.bin/comm/comm.c,v 1.11.2.3 2002/07/11 00:46:37 tjr Exp $
39  * $DragonFly: src/usr.bin/comm/comm.c,v 1.3 2003/10/02 17:42:27 hmp Exp $
40  */
41 
42 #include <ctype.h>
43 #include <err.h>
44 #include <limits.h>
45 #include <locale.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 
51 #define	MAXLINELEN	(LINE_MAX + 1)
52 
53 const char *tabs[] = { "", "\t", "\t\t" };
54 
55 FILE   *file(char *);
56 void	show(FILE *, const char *, char *);
57 int     stricoll(char *, char *);
58 static void	usage(void);
59 
60 int
61 main(int argc, char **argv)
62 {
63 	int comp, file1done = 0, file2done = 0, read1, read2;
64 	int ch, flag1, flag2, flag3, iflag;
65 	FILE *fp1, *fp2;
66 	const char *col1, *col2, *col3;
67 	char line1[MAXLINELEN], line2[MAXLINELEN];
68 	const char **p;
69 
70 	flag1 = flag2 = flag3 = 1;
71 	iflag = 0;
72 
73 	(void) setlocale(LC_ALL, "");
74 
75 	while ((ch = getopt(argc, argv, "123i")) != -1)
76 		switch(ch) {
77 		case '1':
78 			flag1 = 0;
79 			break;
80 		case '2':
81 			flag2 = 0;
82 			break;
83 		case '3':
84 			flag3 = 0;
85 			break;
86 		case 'i':
87 			iflag = 1;
88 			break;
89 		case '?':
90 		default:
91 			usage();
92 		}
93 	argc -= optind;
94 	argv += optind;
95 
96 	if (argc != 2)
97 		usage();
98 
99 	fp1 = file(argv[0]);
100 	fp2 = file(argv[1]);
101 
102 	/* for each column printed, add another tab offset */
103 	p = tabs;
104 	col1 = col2 = col3 = NULL;
105 	if (flag1)
106 		col1 = *p++;
107 	if (flag2)
108 		col2 = *p++;
109 	if (flag3)
110 		col3 = *p;
111 
112 	for (read1 = read2 = 1;;) {
113 		/* read next line, check for EOF */
114 		if (read1)
115 			file1done = !fgets(line1, MAXLINELEN, fp1);
116 		if (read2)
117 			file2done = !fgets(line2, MAXLINELEN, fp2);
118 
119 		/* if one file done, display the rest of the other file */
120 		if (file1done) {
121 			if (!file2done && col2)
122 				show(fp2, col2, line2);
123 			break;
124 		}
125 		if (file2done) {
126 			if (!file1done && col1)
127 				show(fp1, col1, line1);
128 			break;
129 		}
130 
131 		/* lines are the same */
132 		if(iflag)
133 			comp = stricoll(line1, line2);
134 		else
135 			comp = strcoll(line1, line2);
136 
137 		if (!comp) {
138 			read1 = read2 = 1;
139 			if (col3)
140 				(void)printf("%s%s", col3, line1);
141 			continue;
142 		}
143 
144 		/* lines are different */
145 		if (comp < 0) {
146 			read1 = 1;
147 			read2 = 0;
148 			if (col1)
149 				(void)printf("%s%s", col1, line1);
150 		} else {
151 			read1 = 0;
152 			read2 = 1;
153 			if (col2)
154 				(void)printf("%s%s", col2, line2);
155 		}
156 	}
157 	exit(0);
158 }
159 
160 void
161 show(FILE *fp, const char *offset, char *buf)
162 {
163 
164 	do {
165 		(void)printf("%s%s", offset, buf);
166 	} while (fgets(buf, MAXLINELEN, fp));
167 }
168 
169 FILE *
170 file(char *name)
171 {
172 	FILE *fp;
173 
174 	if (!strcmp(name, "-"))
175 		return (stdin);
176 	if ((fp = fopen(name, "r")) == NULL) {
177 		err(1, "%s", name);
178 	}
179 	return (fp);
180 }
181 
182 static void
183 usage(void)
184 {
185 	(void)fprintf(stderr, "usage: comm [-123i] file1 file2\n");
186 	exit(1);
187 }
188 
189 int
190 stricoll(char *s1, char *s2)
191 {
192 	char *p, line1[MAXLINELEN], line2[MAXLINELEN];
193 
194 	for (p = line1; *s1; s1++)
195 		*p++ = tolower((unsigned char)*s1);
196 	*p = '\0';
197 	for (p = line2; *s2; s2++)
198 		*p++ = tolower((unsigned char)*s2);
199 	*p = '\0';
200 	return strcoll(line1, line2);
201 }
202