2 * Copyright (C) 2004-2008 Kay Sievers <kay.sievers@vrfy.org>
3 * Copyright (C) 2009 Canonical Ltd.
4 * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <sys/types.h>
30 #include <sys/inotify.h>
37 /* inotify descriptor, will be shared with rules directory;
38 * set to cloexec since we need our children to be able to add
41 void udev_watch_init(struct udev *udev)
43 inotify_fd = inotify_init();
44 if (inotify_fd >= 0) {
47 flags = fcntl(inotify_fd, F_GETFD);
52 fcntl(inotify_fd, F_SETFD, flags);
53 } else if (errno == ENOSYS)
54 info(udev, "unable to use inotify, udevd will not monitor rule files changes\n");
56 err(udev, "inotify_init failed: %m\n");
59 /* move any old watches directory out of the way, and then restore
62 void udev_watch_restore(struct udev *udev)
64 char filename[UTIL_PATH_SIZE], oldname[UTIL_PATH_SIZE];
69 util_strlcpy(oldname, udev_get_dev_path(udev), sizeof(oldname));
70 util_strlcat(oldname, "/.udev/watch.old", sizeof(oldname));
72 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
73 util_strlcat(filename, "/.udev/watch", sizeof(filename));
75 if (rename(filename, oldname) == 0) {
79 dir = opendir(oldname);
81 err(udev, "unable to open old watches dir '%s', old watches will not be restored: %m", oldname);
85 while ((ent = readdir(dir)) != NULL) {
86 char path[UTIL_PATH_SIZE];
87 char buf[UTIL_PATH_SIZE];
89 struct udev_device *dev;
91 if (ent->d_name[0] < '0' || ent->d_name[0] > '9')
94 util_strlcpy(path, oldname, sizeof(path));
95 util_strlcat(path, "/", sizeof(path));
96 util_strlcat(path, ent->d_name, sizeof(path));
98 len = readlink(path, buf, sizeof(buf));
105 dbg(udev, "old watch to '%s' found\n", buf);
106 dev = udev_device_new_from_syspath(udev, buf);
112 info(udev, "restoring old watch on '%s'\n", udev_device_get_devnode(dev));
113 udev_watch_begin(udev, dev);
115 udev_device_unref(dev);
122 } else if (errno != ENOENT) {
123 err(udev, "unable to move watches dir '%s', old watches will not be restored: %m", filename);
127 static const char *udev_watch_filename(struct udev *udev, int wd)
129 static char filename[UTIL_PATH_SIZE];
132 sprintf(str, "%d", wd);
133 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
134 util_strlcat(filename, "/.udev/watch/", sizeof(filename));
135 util_strlcat(filename, str, sizeof(filename));
140 void udev_watch_begin(struct udev *udev, struct udev_device *dev)
142 const char *filename;
145 if (inotify_fd < 0 || major(udev_device_get_devnum(dev)) == 0)
148 wd = inotify_add_watch(inotify_fd, udev_device_get_devnode(dev), IN_CLOSE_WRITE);
150 err(udev, "inotify_add_watch(%d, %s, %o) failed: %m\n",
151 inotify_fd, udev_device_get_devnode(dev), IN_CLOSE_WRITE);
154 filename = udev_watch_filename(udev, wd);
155 util_create_path(udev, filename);
157 symlink(udev_device_get_syspath(dev), filename);
159 udev_device_set_watch_handle(dev, wd);
160 udev_device_update_db(dev);
163 void udev_watch_end(struct udev *udev, struct udev_device *dev)
166 const char *filename;
168 if (inotify_fd < 0 || major(udev_device_get_devnum(dev)) == 0)
171 wd = udev_device_get_watch_handle(dev);
175 info(udev, "removing watch on '%s'\n", udev_device_get_devnode(dev));
176 inotify_rm_watch(inotify_fd, wd);
178 filename = udev_watch_filename(udev, wd);
181 udev_device_set_watch_handle(dev, -1);
182 udev_device_update_db(dev);
185 struct udev_device *udev_watch_lookup(struct udev *udev, int wd)
187 const char *filename;
188 char buf[UTIL_PATH_SIZE];
191 if (inotify_fd < 0 || wd < 0)
194 filename = udev_watch_filename(udev, wd);
195 len = readlink(filename, buf, sizeof(buf));
199 return udev_device_new_from_syspath(udev, buf);