1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
/*
* Copyright (c) 2005-2016 Apple Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* The contents of this file constitute Original Code as defined in and
* are subject to the Apple Public Source License Version 1.1 (the
* "License"). You may not use this file except in compliance with the
* License. Please obtain a copy of the License at
* http://www.apple.com/publicsource and read it before using this file.
*
* This Original Code and all software distributed under the License are
* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
* License for the specific language governing rights and limitations
* under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
#include <sys/errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <err.h>
#include <fcntl.h>
#include <fstab.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <paths.h>
#include <unistd.h>
#include <signal.h>
#include <libiosexec.h>
char *warning = "\
#\n\
# Warning - this file should only be modified with vifs(8)\n\
#\n\
# Failure to do so is unsupported and may be destructive.\n\
#\n";
int
main(int argc, char *argv[])
{
struct stat sb;
int fd, x;
uid_t euid;
pid_t editpid;
char *p, *editor;
if (argc != 1) {
printf("usage: vifs\n");
exit(1);
}
euid = geteuid();
if (euid != 0)
errx(1, "need to run as root");
/* examine the existing fstab, try to create it if needed */
if (stat(_PATH_FSTAB, &sb) < 0) {
if (errno == ENOENT) {
fd = open(_PATH_FSTAB, O_CREAT | O_WRONLY,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
if (fd < 0)
errx(1, "error creating %s", _PATH_FSTAB);
write(fd, warning, strlen(warning));
close(fd);
} else {
errx(1, "could not stat %s", _PATH_FSTAB);
}
}
/* prepare the file for the editor */
fd = open(_PATH_FSTAB, O_RDONLY, 0);
if (fd < 0)
errx(1, "error opening %s", _PATH_FSTAB);
x = fcntl(fd, F_SETFD, 1);
if (x < 0)
errx(1, "error setting close on exit");
x = flock(fd, LOCK_EX | LOCK_NB);
if (x != 0)
errx(1, "file is busy");
/* obtain and invoke the editor */
editor = getenv("EDITOR");
if (editor == NULL)
editor = _PATH_VI;
p = strrchr(editor, '/');
if (p != NULL)
++p;
else
p = editor;
editpid = vfork();
if (editpid == 0) {
execlp(editor, p, _PATH_FSTAB, NULL);
_exit(1);
}
for ( ; ; ) {
editpid = waitpid(editpid, (int *)&x, WUNTRACED);
if (editpid == -1)
errx(1, "editing error");
else if (WIFSTOPPED(x))
raise(WSTOPSIG(x));
else if (WIFEXITED(x) && WEXITSTATUS(x) == 0)
break;
else
errx(1, "editing error");
}
/* let process death clean up locks and file descriptors */
return 0;
}
|
