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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
|
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright © 2009 Canonical Ltd.
* Copyright © 2009 Scott James Remnant <scott@netsplit.com>
*/
#include <sys/inotify.h>
#include <unistd.h>
#include "alloc-util.h"
#include "device-private.h"
#include "device-util.h"
#include "dirent-util.h"
#include "fs-util.h"
#include "mkdir.h"
#include "stdio-util.h"
#include "udev-watch.h"
static int inotify_fd = -1;
/* inotify descriptor, will be shared with rules directory;
* set to cloexec since we need our children to be able to add
* watches for us. */
int udev_watch_init(void) {
inotify_fd = inotify_init1(IN_CLOEXEC);
if (inotify_fd < 0)
return -errno;
return inotify_fd;
}
/* Move any old watches directory out of the way, and then restore the watches. */
int udev_watch_restore(void) {
struct dirent *ent;
DIR *dir;
int r;
if (inotify_fd < 0)
return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
"Invalid inotify descriptor.");
if (rename("/run/udev/watch", "/run/udev/watch.old") < 0) {
if (errno != ENOENT)
return log_warning_errno(errno, "Failed to move watches directory /run/udev/watch. Old watches will not be restored: %m");
return 0;
}
dir = opendir("/run/udev/watch.old");
if (!dir)
return log_warning_errno(errno, "Failed to open old watches directory /run/udev/watch.old. Old watches will not be restored: %m");
FOREACH_DIRENT_ALL(ent, dir, break) {
_cleanup_(sd_device_unrefp) sd_device *dev = NULL;
_cleanup_free_ char *device = NULL;
if (ent->d_name[0] == '.')
continue;
r = readlinkat_malloc(dirfd(dir), ent->d_name, &device);
if (r < 0) {
log_debug_errno(r, "Failed to read link '/run/udev/watch.old/%s', ignoring: %m", ent->d_name);
goto unlink;
}
r = sd_device_new_from_device_id(&dev, device);
if (r < 0) {
log_debug_errno(r, "Failed to create sd_device object for '%s', ignoring: %m", device);
goto unlink;
}
log_device_debug(dev, "Restoring old watch");
(void) udev_watch_begin(dev);
unlink:
(void) unlinkat(dirfd(dir), ent->d_name, 0);
}
(void) closedir(dir);
(void) rmdir("/run/udev/watch.old");
return 0;
}
int udev_watch_begin(sd_device *dev) {
char filename[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
const char *devnode, *id_filename;
int wd, r;
if (inotify_fd < 0)
return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
"Invalid inotify descriptor.");
r = sd_device_get_devname(dev, &devnode);
if (r < 0)
return log_device_error_errno(dev, r, "Failed to get device name: %m");
log_device_debug(dev, "Adding watch on '%s'", devnode);
wd = inotify_add_watch(inotify_fd, devnode, IN_CLOSE_WRITE);
if (wd < 0)
return log_device_full_errno(dev, errno == ENOENT ? LOG_DEBUG : LOG_ERR, errno,
"Failed to add device '%s' to watch: %m", devnode);
device_set_watch_handle(dev, wd);
xsprintf(filename, "/run/udev/watch/%d", wd);
r = mkdir_parents(filename, 0755);
if (r < 0)
return log_device_error_errno(dev, r, "Failed to create parent directory of '%s': %m", filename);
(void) unlink(filename);
r = device_get_id_filename(dev, &id_filename);
if (r < 0)
return log_device_error_errno(dev, r, "Failed to get device id-filename: %m");
if (symlink(id_filename, filename) < 0)
return log_device_error_errno(dev, errno, "Failed to create symlink %s: %m", filename);
return 0;
}
int udev_watch_end(sd_device *dev) {
char filename[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
int wd, r;
if (inotify_fd < 0)
return 0; /* Nothing to do. */
r = device_get_watch_handle(dev, &wd);
if (r == -ENOENT)
return 0;
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get watch handle, ignoring: %m");
log_device_debug(dev, "Removing watch");
(void) inotify_rm_watch(inotify_fd, wd);
xsprintf(filename, "/run/udev/watch/%d", wd);
(void) unlink(filename);
device_set_watch_handle(dev, -1);
return 0;
}
int udev_watch_lookup(int wd, sd_device **ret) {
char filename[STRLEN("/run/udev/watch/") + DECIMAL_STR_MAX(int)];
_cleanup_free_ char *device = NULL;
int r;
assert(ret);
if (inotify_fd < 0)
return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
"Invalid inotify descriptor.");
if (wd < 0)
return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
"Invalid watch handle.");
xsprintf(filename, "/run/udev/watch/%d", wd);
r = readlink_malloc(filename, &device);
if (r == -ENOENT)
return 0;
if (r < 0)
return log_debug_errno(r, "Failed to read link '%s': %m", filename);
r = sd_device_new_from_device_id(ret, device);
if (r == -ENODEV)
return 0;
if (r < 0)
return log_debug_errno(r, "Failed to create sd_device object for '%s': %m", device);
return 1;
}
|
