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];
90 struct udev_device *dev;
92 if (ent->d_name[0] < '0' || ent->d_name[0] > '9')
95 util_strlcpy(path, oldname, sizeof(path));
96 util_strlcat(path, "/", sizeof(path));
97 util_strlcat(path, ent->d_name, sizeof(path));
99 syslen = util_strlcpy(buf, udev_get_sys_path(udev), sizeof(buf));
100 len = readlink(path, &buf[syslen], sizeof(buf)-syslen);
101 if (len <= 0 || len >= (ssize_t)(sizeof(buf)-syslen)) {
105 buf[syslen + len] = '\0';
106 dbg(udev, "old watch to '%s' found\n", buf);
107 dev = udev_device_new_from_syspath(udev, buf);
113 info(udev, "restoring old watch on '%s'\n", udev_device_get_devnode(dev));
114 udev_watch_begin(udev, dev);
116 udev_device_unref(dev);
123 } else if (errno != ENOENT) {
124 err(udev, "unable to move watches dir '%s', old watches will not be restored: %m", filename);
128 void udev_watch_begin(struct udev *udev, struct udev_device *dev)
130 char filename[UTIL_PATH_SIZE];
136 info(udev, "adding watch on '%s'\n", udev_device_get_devnode(dev));
137 wd = inotify_add_watch(inotify_fd, udev_device_get_devnode(dev), IN_CLOSE_WRITE);
139 err(udev, "inotify_add_watch(%d, %s, %o) failed: %m\n",
140 inotify_fd, udev_device_get_devnode(dev), IN_CLOSE_WRITE);
143 snprintf(filename, sizeof(filename), "%s/.udev/watch/%d", udev_get_dev_path(udev), wd);
144 util_create_path(udev, filename);
146 symlink(udev_device_get_devpath(dev), filename);
148 udev_device_set_watch_handle(dev, wd);
151 void udev_watch_end(struct udev *udev, struct udev_device *dev)
154 char filename[UTIL_PATH_SIZE];
159 wd = udev_device_get_watch_handle(dev);
163 info(udev, "removing watch on '%s'\n", udev_device_get_devnode(dev));
164 inotify_rm_watch(inotify_fd, wd);
166 snprintf(filename, sizeof(filename), "%s/.udev/watch/%d", udev_get_dev_path(udev), wd);
169 udev_device_set_watch_handle(dev, -1);
172 struct udev_device *udev_watch_lookup(struct udev *udev, int wd)
174 char filename[UTIL_PATH_SIZE];
175 char buf[UTIL_PATH_SIZE];
179 if (inotify_fd < 0 || wd < 0)
182 snprintf(filename, sizeof(filename), "%s/.udev/watch/%d", udev_get_dev_path(udev), wd);
183 syslen = util_strlcpy(buf, udev_get_sys_path(udev), sizeof(buf));
184 len = readlink(filename, &buf[syslen], sizeof(buf)-syslen);
185 if (len > 0 || len < (ssize_t)(sizeof(buf)-syslen)) {
186 buf[syslen + len] = '\0';
187 return udev_device_new_from_syspath(udev, buf);