1 /*
2 * SPDX-License-Identifier: BSD-3-Clause
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 * $FreeBSD: head/usr.bin/cmp/cmp.c 216370 2010-12-11 08:32:16Z joel $
32 *
33 * @(#) Copyright (c) 1987, 1990, 1993, 1994 The Regents of the University of California. All rights reserved.
34 * @(#)cmp.c 8.3 (Berkeley) 4/2/94
35 */
36
37 #include <sys/types.h>
38 #include <sys/stat.h>
39
40 #include <err.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 #include <getopt.h>
44 #include <nl_types.h>
45 #include <stdbool.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50
51 #include "extern.h"
52
53 bool lflag, sflag, xflag, zflag;
54
55 static const struct option long_opts[] =
56 {
57 {"verbose", no_argument, NULL, 'l'},
58 {"silent", no_argument, NULL, 's'},
59 {"quiet", no_argument, NULL, 's'},
60 {NULL, no_argument, NULL, 0}
61 };
62
63 static void usage(void);
64
65 int
main(int argc,char * argv[])66 main(int argc, char *argv[])
67 {
68 struct stat sb1, sb2;
69 off_t skip1, skip2;
70 int ch, fd1, fd2, oflag;
71 bool special;
72 const char *file1, *file2;
73
74 oflag = O_RDONLY;
75 while ((ch = getopt_long(argc, argv, "+hlsxz", long_opts, NULL)) != -1)
76 switch (ch) {
77 case 'h': /* Don't follow symlinks */
78 oflag |= O_NOFOLLOW;
79 break;
80 case 'l': /* print all differences */
81 lflag = true;
82 break;
83 case 's': /* silent run */
84 sflag = true;
85 break;
86 case 'x': /* hex output */
87 lflag = true;
88 xflag = true;
89 break;
90 case 'z': /* compare size first */
91 zflag = true;
92 break;
93 case '?':
94 default:
95 usage();
96 }
97 argv += optind;
98 argc -= optind;
99
100 if (lflag && sflag)
101 errx(ERR_EXIT, "specifying -s with -l or -x is not permitted");
102
103 if (argc < 2 || argc > 4)
104 usage();
105
106 /* Backward compatibility -- handle "-" meaning stdin. */
107 special = false;
108 if (strcmp(file1 = argv[0], "-") == 0) {
109 special = true;
110 fd1 = STDIN_FILENO;
111 file1 = "stdin";
112 } else if ((fd1 = open(file1, oflag, 0)) < 0 && errno != EMLINK) {
113 if (!sflag)
114 err(ERR_EXIT, "%s", file1);
115 else
116 exit(ERR_EXIT);
117 }
118 if (strcmp(file2 = argv[1], "-") == 0) {
119 if (special)
120 errx(ERR_EXIT,
121 "standard input may only be specified once");
122 special = true;
123 fd2 = STDIN_FILENO;
124 file2 = "stdin";
125 } else if ((fd2 = open(file2, oflag, 0)) < 0 && errno != EMLINK) {
126 if (!sflag)
127 err(ERR_EXIT, "%s", file2);
128 else
129 exit(ERR_EXIT);
130 }
131
132 skip1 = argc > 2 ? strtol(argv[2], NULL, 0) : 0;
133 skip2 = argc == 4 ? strtol(argv[3], NULL, 0) : 0;
134
135 if (sflag && skip1 == 0 && skip2 == 0)
136 zflag = true;
137
138 if (fd1 == -1) {
139 if (fd2 == -1) {
140 c_link(file1, skip1, file2, skip2);
141 exit(0);
142 } else if (!sflag)
143 errx(ERR_EXIT, "%s: Not a symbolic link", file2);
144 else
145 exit(ERR_EXIT);
146 } else if (fd2 == -1) {
147 if (!sflag)
148 errx(ERR_EXIT, "%s: Not a symbolic link", file1);
149 else
150 exit(ERR_EXIT);
151 }
152
153 if (!special) {
154 if (fstat(fd1, &sb1)) {
155 if (!sflag)
156 err(ERR_EXIT, "%s", file1);
157 else
158 exit(ERR_EXIT);
159 }
160 if (!S_ISREG(sb1.st_mode))
161 special = true;
162 else {
163 if (fstat(fd2, &sb2)) {
164 if (!sflag)
165 err(ERR_EXIT, "%s", file2);
166 else
167 exit(ERR_EXIT);
168 }
169 if (!S_ISREG(sb2.st_mode))
170 special = true;
171 }
172 }
173
174 if (special)
175 c_special(fd1, file1, skip1, fd2, file2, skip2);
176 else {
177 if (zflag && sb1.st_size != sb2.st_size) {
178 if (!sflag)
179 (void) printf("%s %s differ: size\n",
180 file1, file2);
181 exit(DIFF_EXIT);
182 }
183 c_regular(fd1, file1, skip1, sb1.st_size,
184 fd2, file2, skip2, sb2.st_size);
185 }
186 exit(0);
187 }
188
189 static void
usage(void)190 usage(void)
191 {
192
193 (void)fprintf(stderr,
194 "usage: cmp [-l | -s | -x] [-hz] file1 file2 [skip1 [skip2]]\n");
195 exit(ERR_EXIT);
196 }
197