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Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <stdio.h>
28#include <stdlib.h>
29#include <sys/stat.h>
30#include <unistd.h>
31
32inline constexpr unsigned encoded_device(unsigned major, unsigned minor)
33{
34 return (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12);
35}
36
37static int usage()
38{
39 printf("usage: mknod <name> <c|b|p> <major> <minor>\n");
40 return 0;
41}
42
43int main(int argc, char** argv)
44{
45 if (pledge("stdio dpath", nullptr) < 0) {
46 perror("pledge");
47 return 1;
48 }
49
50 // FIXME: When invoked with type "p", no need for major/minor numbers.
51 // FIXME: Add some kind of option for specifying the file permissions.
52 if (argc != 5)
53 return usage();
54
55 const char* name = argv[1];
56 mode_t mode = 0666;
57 switch (argv[2][0]) {
58 case 'c':
59 case 'u':
60 mode |= S_IFCHR;
61 break;
62 case 'b':
63 mode |= S_IFBLK;
64 break;
65 case 'p':
66 mode |= S_IFIFO;
67 break;
68 default:
69 return usage();
70 }
71
72 int major = atoi(argv[3]);
73 int minor = atoi(argv[4]);
74
75 int rc = mknod(name, mode, encoded_device(major, minor));
76 if (rc < 0) {
77 perror("mknod");
78 return 1;
79 }
80 return 0;
81}