1 /* $NetBSD: cmp.c,v 1.21 2021/03/20 14:27:47 cheusov Exp $ */
2
3 /*
4 * Copyright (c) 1987, 1990, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1987, 1990, 1993, 1994\
35 The Regents of the University of California. All rights reserved.");
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)cmp.c 8.3 (Berkeley) 4/2/94";
41 #else
42 __RCSID("$NetBSD: cmp.c,v 1.21 2021/03/20 14:27:47 cheusov Exp $");
43 #endif
44 #endif /* not lint */
45
46 #include <sys/types.h>
47 #include <sys/stat.h>
48
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <locale.h>
57
58 #include "extern.h"
59
60 int lflag, sflag;
61
62 __dead static void usage(void);
63
64 int
main(int argc,char * argv[])65 main(int argc, char *argv[])
66 {
67 struct stat sb1, sb2;
68 off_t skip1 = 0, skip2 = 0;
69 int ch, fd1, fd2, special;
70 const char *file1, *file2;
71
72 setlocale(LC_ALL, "");
73
74 special = 0;
75 while ((ch = getopt(argc, argv, "cls")) != -1)
76 switch (ch) {
77 case 'c':
78 special = 1; /* careful! Don't use mmap() */
79 break;
80 case 'l': /* print all differences */
81 lflag = 1;
82 break;
83 case 's': /* silent run */
84 sflag = 1;
85 break;
86 case '?':
87 default:
88 usage();
89 }
90 argv += optind;
91 argc -= optind;
92
93 if (lflag && sflag)
94 errx(ERR_EXIT, "only one of -l and -s may be specified");
95
96 if (argc < 2 || argc > 4)
97 usage();
98
99 /* Backward compatibility -- handle "-" meaning stdin. */
100 if (strcmp(file1 = argv[0], "-") == 0) {
101 special = 1;
102 fd1 = 0;
103 file1 = "stdin";
104 }
105 else if ((fd1 = open(file1, O_RDONLY, 0)) < 0) {
106 if (!sflag)
107 warn("%s", file1);
108 exit(ERR_EXIT);
109 }
110 if (strcmp(file2 = argv[1], "-") == 0) {
111 if (special)
112 errx(ERR_EXIT,
113 "standard input may only be specified once");
114 special = 1;
115 fd2 = 0;
116 file2 = "stdin";
117 }
118 else if ((fd2 = open(file2, O_RDONLY, 0)) < 0) {
119 if (!sflag)
120 warn("%s", file2);
121 exit(ERR_EXIT);
122 }
123
124 if (argc > 2) {
125 char *ep;
126
127 errno = 0;
128 skip1 = (off_t)strtoll(argv[2], &ep, 0);
129 if (errno || ep == argv[2])
130 usage();
131
132 if (argc == 4) {
133 skip2 = (off_t)strtoll(argv[3], &ep, 0);
134 if (errno || ep == argv[3])
135 usage();
136 }
137 }
138
139 if (!special) {
140 if (fstat(fd1, &sb1))
141 err(ERR_EXIT, "%s", file1);
142 if (!S_ISREG(sb1.st_mode))
143 special = 1;
144 else {
145 if (fstat(fd2, &sb2))
146 err(ERR_EXIT, "%s", file2);
147 if (!S_ISREG(sb2.st_mode))
148 special = 1;
149 }
150 }
151
152 if (special)
153 c_special(fd1, file1, skip1, fd2, file2, skip2);
154 else
155 c_regular(fd1, file1, skip1, sb1.st_size,
156 fd2, file2, skip2, sb2.st_size);
157 exit(0);
158 }
159
160 static void
usage(void)161 usage(void)
162 {
163
164 (void)fprintf(stderr,
165 "Usage: %s [-c] [-l | -s] file1 file2 [skip1 [skip2]]\n",
166 getprogname());
167 exit(ERR_EXIT);
168 }
169