move rules dirs to udev context; replace inotify with time-controlled stat()

[elogind.git] / udev / udevd.c

diff --git a/udev/udevd.c b/udev/udevd.c
index 37eb4ba4b13c1b6ab23fb3df0be8fc08d9c71d8e..f810b9431c6410bcdcd0ecf4bf774abd6300608f 100644 (file)
--- a/udev/udevd.c
+++ b/udev/udevd.c
@@ -736,19 +736,6 @@ static int handle_inotify(struct udev *udev)
                struct udev_device *dev;
 
                ev = (struct inotify_event *)(buf + pos);
-               if (ev->len) {
-                       const char *s;
-
-                       info(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
-                       s = strstr(ev->name, ".rules");
-                       if (s == NULL)
-                               continue;
-                       if (strlen(s) != strlen(".rules"))
-                               continue;
-                       reload = true;
-                       continue;
-               }
-
                dev = udev_watch_lookup(udev, ev->wd);
                if (dev != NULL) {
                        info(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
@@ -1169,6 +1156,36 @@ static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
        return 0;
 }
 
+static bool check_rules_timestamp(struct udev *udev)
+{
+       char **p;
+       unsigned long long *stamp_usec;
+       int i, n;
+       bool changed = false;
+
+       n = udev_get_rules_path(udev, &p, &stamp_usec);
+       for (i = 0; i < n; i++) {
+               struct stat stats;
+
+               if (stat(p[i], &stats) < 0)
+                       continue;
+
+               if (stamp_usec[i] == ts_usec(&stats.st_mtim))
+                       continue;
+
+               /* first check */
+               if (stamp_usec[i] != 0) {
+                       info(udev, "reload - timestamp of '%s' changed\n", p[i]);
+                       changed = true;
+               }
+
+               /* update timestamp */
+               stamp_usec[i] = ts_usec(&stats.st_mtim);
+       }
+
+       return changed;
+}
+
 int main(int argc, char *argv[])
 {
        struct udev *udev;
@@ -1191,6 +1208,7 @@ int main(int argc, char *argv[])
        int fd_worker = -1;
        struct epoll_event ep_ctrl, ep_inotify, ep_signal, ep_netlink, ep_worker;
        struct udev_ctrl_connection *ctrl_conn = NULL;
+       char **s;
        int rc = 1;
 
        udev = udev_new();
@@ -1202,31 +1220,6 @@ int main(int argc, char *argv[])
        info(udev, "version %s\n", VERSION);
        udev_selinux_init(udev);
 
-       /* make sure, that our runtime dir exists and is writable */
-       if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) < 0) {
-               /* try to create our own subdirectory, do not create parent directories */
-               mkdir(udev_get_run_config_path(udev), 0755);
-
-               if (utimensat(AT_FDCWD, udev_get_run_config_path(udev), NULL, 0) >= 0) {
-                       /* directory seems writable now */
-                       udev_set_run_path(udev, udev_get_run_config_path(udev));
-               } else {
-                       /* fall back to /dev/.udev */
-                       char filename[UTIL_PATH_SIZE];
-
-                       util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev", NULL);
-                       if (udev_set_run_path(udev, filename) == NULL)
-                               goto exit;
-                       mkdir(udev_get_run_path(udev), 0755);
-                       err(udev, "error: runtime directory '%s' not writable, for now falling back to '%s'",
-                           udev_get_run_config_path(udev), udev_get_run_path(udev));
-               }
-       }
-       /* relabel runtime dir only if it resides below /dev */
-       if (strncmp(udev_get_run_path(udev), udev_get_dev_path(udev), strlen(udev_get_dev_path(udev))) == 0)
-               udev_selinux_lsetfilecon(udev, udev_get_run_path(udev), 0755);
-       info(udev, "runtime dir '%s'\n", udev_get_run_path(udev));
-
        for (;;) {
                int option;
 
@@ -1469,28 +1462,6 @@ int main(int argc, char *argv[])
                rc = 4;
                goto exit;
        }
-
-       if (udev_get_rules_path(udev) != NULL) {
-               inotify_add_watch(fd_inotify, udev_get_rules_path(udev),
-                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
-       } else {
-               char filename[UTIL_PATH_SIZE];
-               struct stat statbuf;
-
-               inotify_add_watch(fd_inotify, LIBEXECDIR "/rules.d",
-                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
-               inotify_add_watch(fd_inotify, SYSCONFDIR "/udev/rules.d",
-                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
-
-               /* watch dynamic rules directory */
-               util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev), "/rules.d", NULL);
-               if (stat(filename, &statbuf) != 0) {
-                       util_create_path(udev, filename);
-                       mkdir(filename, 0755);
-               }
-               inotify_add_watch(fd_inotify, filename,
-                                 IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
-       }
        udev_watch_restore(udev);
 
        /* block and listen to all signals on signalfd */
@@ -1575,6 +1546,7 @@ int main(int argc, char *argv[])
        udev_list_node_init(&worker_list);
 
        for (;;) {
+               static unsigned long long last_usec;
                struct epoll_event ev[8];
                int fdcount;
                int timeout;
@@ -1642,6 +1614,24 @@ int main(int argc, char *argv[])
                                is_ctrl = true;
                }
 
+               /* check for changed config, every 3 seconds at most */
+               if ((now_usec() - last_usec) > 3 * 1000 * 1000) {
+                       if (check_rules_timestamp(udev))
+                               reload = true;
+                       if (udev_builtin_validate(udev))
+                               reload = true;
+
+                       last_usec = now_usec();
+               }
+
+               /* reload requested, HUP signal received, rules changed, builtin changed */
+               if (reload) {
+                       worker_kill(udev, 0);
+                       rules = udev_rules_unref(rules);
+                       udev_builtin_exit(udev);
+                       reload = 0;
+               }
+
                /* event has finished */
                if (is_worker)
                        worker_returned(fd_worker);
@@ -1678,7 +1668,7 @@ int main(int argc, char *argv[])
                if (udev_exit)
                        continue;
 
-               /* device node and rules directory inotify watch */
+               /* device node watch */
                if (is_inotify)
                        handle_inotify(udev);
 
@@ -1693,14 +1683,6 @@ int main(int argc, char *argv[])
                 */
                if (is_ctrl)
                        ctrl_conn = handle_ctrl_msg(udev_ctrl);
-
-               /* rules changed, set by inotify or a HUP signal */
-               if (reload) {
-                       worker_kill(udev, 0);
-                       rules = udev_rules_unref(rules);
-                       udev_builtin_exit(udev);
-                       reload = 0;
-               }
        }
 
        rc = EXIT_SUCCESS;