2 * Copyright (C) 2004-2008 Kay Sievers <kay.sievers@vrfy.org>
3 * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
30 #include <sys/select.h>
33 #include <sys/ioctl.h>
35 #include <sys/inotify.h>
40 #define UDEVD_PRIORITY -4
41 #define UDEV_PRIORITY -2
43 /* maximum limit of forked childs */
44 #define UDEVD_MAX_CHILDS 256
48 static void log_fn(struct udev *udev, int priority,
49 const char *file, int line, const char *fn,
50 const char *format, va_list args)
53 fprintf(stderr, "[%d] %s: ", (int) getpid(), fn);
54 vfprintf(stderr, format, args);
56 vsyslog(priority, format, args);
60 static int debug_trace;
61 static struct udev_rules *rules;
62 static struct udev_ctrl *udev_ctrl;
63 static struct udev_monitor *kernel_monitor;
64 static int inotify_fd = -1;
65 static int signal_pipe[2] = {-1, -1};
66 static volatile int sigchilds_waiting;
67 static volatile int udev_exit;
68 static volatile int reload_config;
69 static int run_exec_q;
70 static int stop_exec_q;
71 static int max_childs;
73 static struct udev_list_node event_list;
81 static struct udev_event *node_to_event(struct udev_list_node *node)
86 event -= offsetof(struct udev_event, node);
87 return (struct udev_event *)event;
90 static void export_event_state(struct udev_event *event, enum event_state state)
92 char filename[UTIL_PATH_SIZE];
93 char filename_failed[UTIL_PATH_SIZE];
96 /* location of queue file */
97 snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu",
98 udev_get_dev_path(event->udev), udev_device_get_seqnum(event->dev));
100 /* location of failed file */
101 util_strlcpy(filename_failed, udev_get_dev_path(event->udev), sizeof(filename_failed));
102 util_strlcat(filename_failed, "/", sizeof(filename_failed));
103 start = util_strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed));
104 util_strlcat(filename_failed, udev_device_get_devpath(event->dev), sizeof(filename_failed));
105 util_path_encode(&filename_failed[start], sizeof(filename_failed) - start);
109 if(unlink(filename_failed) == 0)
110 util_delete_path(event->udev, filename_failed);
111 util_create_path(event->udev, filename);
112 udev_selinux_setfscreatecon(event->udev, filename, S_IFLNK);
113 symlink(udev_device_get_devpath(event->dev), filename);
114 udev_selinux_resetfscreatecon(event->udev);
117 if (udev_device_get_devpath_old(event->dev) != NULL) {
118 /* "move" event - rename failed file to current name, do not delete failed */
119 char filename_failed_old[UTIL_PATH_SIZE];
121 util_strlcpy(filename_failed_old, udev_get_dev_path(event->udev), sizeof(filename_failed_old));
122 util_strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
123 start = util_strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old));
124 util_strlcat(filename_failed_old, udev_device_get_devpath_old(event->dev), sizeof(filename_failed_old));
125 util_path_encode(&filename_failed_old[start], sizeof(filename) - start);
127 if (rename(filename_failed_old, filename_failed) == 0)
128 info(event->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
129 udev_device_get_devpath_old(event->dev), udev_device_get_devpath(event->dev));
131 if (unlink(filename_failed) == 0)
132 util_delete_path(event->udev, filename_failed);
137 /* clean up possibly empty queue directory */
138 if (udev_list_is_empty(&event_list))
139 util_delete_path(event->udev, filename);
142 /* move failed event to the failed directory */
143 util_create_path(event->udev, filename_failed);
144 rename(filename, filename_failed);
146 /* clean up possibly empty queue directory */
147 if (udev_list_is_empty(&event_list))
148 util_delete_path(event->udev, filename);
155 static void event_queue_delete(struct udev_event *event)
157 udev_list_node_remove(&event->node);
159 /* mark as failed, if "add" event returns non-zero */
160 if (event->exitstatus && strcmp(udev_device_get_action(event->dev), "add") == 0)
161 export_event_state(event, EVENT_FAILED);
163 export_event_state(event, EVENT_FINISHED);
165 udev_device_unref(event->dev);
166 udev_event_unref(event);
169 static void asmlinkage event_sig_handler(int signum)
171 if (signum == SIGALRM)
175 static void event_fork(struct udev_event *event)
178 struct sigaction act;
183 fprintf(stderr, "fork %s (%llu)\n",
184 udev_device_get_syspath(event->dev),
185 udev_device_get_seqnum(event->dev));
192 udev_monitor_unref(kernel_monitor);
193 udev_ctrl_unref(udev_ctrl);
196 close(signal_pipe[READ_END]);
197 close(signal_pipe[WRITE_END]);
199 logging_init("udevd-event");
200 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
202 /* set signal handlers */
203 memset(&act, 0x00, sizeof(act));
204 act.sa_handler = (void (*)(int)) event_sig_handler;
205 sigemptyset (&act.sa_mask);
207 sigaction(SIGALRM, &act, NULL);
209 /* reset to default */
210 act.sa_handler = SIG_DFL;
211 sigaction(SIGINT, &act, NULL);
212 sigaction(SIGTERM, &act, NULL);
213 sigaction(SIGCHLD, &act, NULL);
214 sigaction(SIGHUP, &act, NULL);
216 /* set timeout to prevent hanging processes */
217 alarm(UDEV_EVENT_TIMEOUT);
219 /* apply rules, create node, symlinks */
220 err = udev_event_execute_rules(event, rules);
222 /* rules may change/disable the timeout */
223 if (udev_device_get_event_timeout(event->dev) >= 0)
224 alarm(udev_device_get_event_timeout(event->dev));
227 if (err == 0 && !event->ignore_device && udev_get_run(event->udev))
228 udev_event_execute_run(event);
230 info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err);
236 err(event->udev, "fork of child failed: %m\n");
237 event_queue_delete(event);
240 /* get SIGCHLD in main loop */
241 info(event->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
242 udev_device_get_seqnum(event->dev),
244 udev_device_get_action(event->dev),
245 udev_device_get_subsystem(event->dev),
246 time(NULL) - event->queue_time);
252 static void event_queue_insert(struct udev_event *event)
254 char filename[UTIL_PATH_SIZE];
257 event->queue_time = time(NULL);
259 export_event_state(event, EVENT_QUEUED);
260 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(event->dev),
261 udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev));
263 util_strlcpy(filename, udev_get_dev_path(event->udev), sizeof(filename));
264 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
265 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
270 len = sprintf(str, "%llu\n", udev_device_get_seqnum(event->dev));
276 udev_list_node_append(&event->node, &event_list);
279 /* run all events with a timeout set immediately */
280 if (udev_device_get_timeout(event->dev) > 0) {
286 static int mem_size_mb(void)
290 long int memsize = -1;
292 f = fopen("/proc/meminfo", "r");
296 while (fgets(buf, sizeof(buf), f) != NULL) {
299 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
300 memsize = value / 1024;
309 static int compare_devpath(const char *running, const char *waiting)
313 while (running[i] != '\0' && running[i] == waiting[i])
316 /* identical device event found */
317 if (running[i] == '\0' && waiting[i] == '\0')
320 /* parent device event found */
321 if (running[i] == '\0' && waiting[i] == '/')
324 /* child device event found */
325 if (running[i] == '/' && waiting[i] == '\0')
328 /* no matching event */
332 /* lookup event for identical, parent, child, or physical device */
333 static int devpath_busy(struct udev_event *event)
335 struct udev_list_node *loop;
337 if (event->delaying_seqnum > 0) {
339 /* check if queue contains events we depend on */
340 udev_list_node_foreach(loop, &event_list) {
341 struct udev_event *loop_event = node_to_event(loop);
343 /* we already found a later event, earlier can not block us, no need to check again */
344 if (udev_device_get_seqnum(loop_event->dev) < event->delaying_seqnum)
347 /* event we checked earlier still exists, no need to check again */
348 if (udev_device_get_seqnum(loop_event->dev) == event->delaying_seqnum)
351 /* found ourself, no later event can block us */
352 if (udev_device_get_seqnum(loop_event->dev) >= udev_device_get_seqnum(event->dev))
355 /* check our old name */
356 if (udev_device_get_devpath_old(event->dev) != NULL)
357 if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0) {
358 event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev);
362 /* check identical, parent, or child device event */
363 if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) {
364 dbg(event->udev, "%llu, device event still pending %llu (%s)\n",
365 udev_device_get_seqnum(event->dev),
366 udev_device_get_seqnum(loop_event->dev),
367 udev_device_get_devpath(loop_event->dev));
368 event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev);
372 /* check for our major:minor number */
373 if (major(udev_device_get_devnum(event->dev)) > 0 &&
374 udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) &&
375 strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) {
376 dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n",
377 udev_device_get_seqnum(event->dev),
378 udev_device_get_seqnum(loop_event->dev),
379 major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev)));
380 event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev);
384 /* check physical device event (special case of parent) */
385 if (udev_device_get_physdevpath(event->dev) != NULL &&
386 strcmp(udev_device_get_action(event->dev), "add") == 0)
387 if (compare_devpath(udev_device_get_devpath(loop_event->dev),
388 udev_device_get_physdevpath(event->dev)) != 0) {
389 dbg(event->udev, "%llu, physical device event still pending %llu (%s)\n",
390 udev_device_get_seqnum(event->dev),
391 udev_device_get_seqnum(loop_event->dev),
392 udev_device_get_devpath(loop_event->dev));
393 event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev);
400 /* serializes events for the identical and parent and child devices */
401 static void event_queue_manager(struct udev *udev)
403 struct udev_list_node *loop;
404 struct udev_list_node *tmp;
406 if (udev_list_is_empty(&event_list)) {
408 err(udev, "event list empty, but childs count is %i", childs);
414 udev_list_node_foreach_safe(loop, tmp, &event_list) {
415 struct udev_event *loop_event = node_to_event(loop);
417 if (childs >= max_childs) {
418 info(udev, "maximum number (%i) of childs reached\n", childs);
422 if (loop_event->pid != 0)
425 /* do not start event if parent or child event is still running */
426 if (devpath_busy(loop_event) != 0) {
427 dbg(udev, "delay seq %llu (%s)\n",
428 udev_device_get_seqnum(loop_event->dev),
429 udev_device_get_devpath(loop_event->dev));
433 event_fork(loop_event);
434 dbg(udev, "moved seq %llu to running list\n", udev_device_get_seqnum(loop_event->dev));
438 /* receive the udevd message from userspace */
439 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
441 struct udev *udev = udev_ctrl_get_udev(uctrl);
442 struct udev_ctrl_msg *ctrl_msg;
446 ctrl_msg = udev_ctrl_receive_msg(uctrl);
447 if (ctrl_msg == NULL)
450 i = udev_ctrl_get_set_log_level(ctrl_msg);
452 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
453 udev_set_log_priority(udev, i);
456 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
457 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
461 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
462 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
464 event_queue_manager(udev);
467 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
468 info(udev, "udevd message (RELOAD_RULES) received\n");
472 str = udev_ctrl_get_set_env(ctrl_msg);
480 val = strchr(key, '=');
484 if (val[0] == '\0') {
485 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
486 udev_add_property(udev, key, NULL);
488 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
489 udev_add_property(udev, key, val);
492 err(udev, "wrong key format '%s'\n", key);
498 i = udev_ctrl_get_set_max_childs(ctrl_msg);
500 info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
503 udev_ctrl_msg_unref(ctrl_msg);
506 static void asmlinkage sig_handler(int signum)
514 /* set flag, then write to pipe if needed */
515 sigchilds_waiting = 1;
522 /* write to pipe, which will wakeup select() in our mainloop */
523 write(signal_pipe[WRITE_END], "", 1);
526 static void udev_done(int pid, int exitstatus)
528 struct udev_list_node *loop;
530 /* find event associated with pid and delete it */
531 udev_list_node_foreach(loop, &event_list) {
532 struct udev_event *loop_event = node_to_event(loop);
534 if (loop_event->pid == pid) {
535 info(loop_event->udev, "seq %llu cleanup, pid [%d], status %i, %ld seconds old\n",
536 udev_device_get_seqnum(loop_event->dev), loop_event->pid,
537 exitstatus, time(NULL) - loop_event->queue_time);
538 loop_event->exitstatus = exitstatus;
540 fprintf(stderr, "exit %s (%llu)\n",
541 udev_device_get_syspath(loop_event->dev),
542 udev_device_get_seqnum(loop_event->dev));
543 event_queue_delete(loop_event);
546 /* there may be dependent events waiting */
553 static void reap_sigchilds(void)
559 pid = waitpid(-1, &status, WNOHANG);
562 if (WIFEXITED(status))
563 status = WEXITSTATUS(status);
564 else if (WIFSIGNALED(status))
565 status = WTERMSIG(status) + 128;
568 udev_done(pid, status);
572 static void export_initial_seqnum(struct udev *udev)
574 char filename[UTIL_PATH_SIZE];
579 util_strlcpy(filename, udev_get_sys_path(udev), sizeof(filename));
580 util_strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
581 fd = open(filename, O_RDONLY);
583 len = read(fd, seqnum, sizeof(seqnum)-1);
587 strcpy(seqnum, "0\n");
590 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
591 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
592 util_create_path(udev, filename);
593 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
595 write(fd, seqnum, len);
600 int main(int argc, char *argv[])
605 struct sigaction act;
609 static const struct option options[] = {
610 { "daemon", no_argument, NULL, 'd' },
611 { "debug-trace", no_argument, NULL, 't' },
612 { "debug", no_argument, NULL, 'D' },
613 { "help", no_argument, NULL, 'h' },
614 { "version", no_argument, NULL, 'V' },
624 logging_init("udevd");
625 udev_set_log_fn(udev, log_fn);
626 info(udev, "version %s\n", VERSION);
627 udev_selinux_init(udev);
632 option = getopt_long(argc, argv, "dDthV", options, NULL);
645 if (udev_get_log_priority(udev) < LOG_INFO)
646 udev_set_log_priority(udev, LOG_INFO);
649 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
652 printf("%s\n", VERSION);
660 fprintf(stderr, "root privileges required\n");
661 err(udev, "root privileges required\n");
665 /* make sure std{in,out,err} fd's are in a sane state */
666 fd = open("/dev/null", O_RDWR);
668 fprintf(stderr, "cannot open /dev/null\n");
669 err(udev, "cannot open /dev/null\n");
671 if (write(STDOUT_FILENO, 0, 0) < 0)
672 dup2(fd, STDOUT_FILENO);
673 if (write(STDERR_FILENO, 0, 0) < 0)
674 dup2(fd, STDERR_FILENO);
676 /* init control socket, bind() ensures, that only one udevd instance is running */
677 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
678 if (udev_ctrl == NULL) {
679 fprintf(stderr, "error initializing control socket");
680 err(udev, "error initializing udevd socket");
685 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
686 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
687 err(udev, "error binding control socket, seems udevd is already running\n");
692 kernel_monitor = udev_monitor_new_from_netlink(udev);
693 if (kernel_monitor == NULL || udev_monitor_enable_receiving(kernel_monitor) < 0) {
694 fprintf(stderr, "error initializing netlink socket\n");
695 err(udev, "error initializing netlink socket\n");
699 udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
701 err = pipe(signal_pipe);
703 err(udev, "error getting pipes: %m\n");
707 err = fcntl(signal_pipe[READ_END], F_GETFL, 0);
709 err(udev, "error fcntl on read pipe: %m\n");
712 err = fcntl(signal_pipe[READ_END], F_SETFL, err | O_NONBLOCK);
714 err(udev, "error fcntl on read pipe: %m\n");
718 err = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
720 err(udev, "error fcntl on write pipe: %m\n");
723 err = fcntl(signal_pipe[WRITE_END], F_SETFL, err | O_NONBLOCK);
725 err(udev, "error fcntl on write pipe: %m\n");
729 rules = udev_rules_new(udev, 1);
731 err(udev, "error reading rules\n");
734 udev_list_init(&event_list);
735 export_initial_seqnum(udev);
743 dbg(udev, "daemonized fork running\n");
746 err(udev, "fork of daemon failed: %m\n");
750 dbg(udev, "child [%u] running, parent exits\n", pid);
756 /* redirect std{out,err} */
757 if (!debug && !debug_trace) {
758 dup2(fd, STDIN_FILENO);
759 dup2(fd, STDOUT_FILENO);
760 dup2(fd, STDERR_FILENO);
762 if (fd > STDERR_FILENO)
765 /* set scheduling priority for the daemon */
766 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
772 /* OOM_DISABLE == -17 */
773 fd = open("/proc/self/oom_adj", O_RDWR);
775 err(udev, "error disabling OOM: %m\n");
781 fd = open("/dev/kmsg", O_WRONLY);
783 const char *ver_str = "<6>udev: starting version " VERSION "\n";
784 char path[UTIL_PATH_SIZE];
787 write(fd, ver_str, strlen(ver_str));
788 util_strlcpy(path, udev_get_sys_path(udev), sizeof(path));
789 util_strlcat(path, "/class/mem/null", sizeof(path));
790 if (lstat(path, &statbuf) == 0) {
791 if (S_ISDIR(statbuf.st_mode)) {
792 const char *depr_str = "<6>udev: deprecated sysfs layout (kernel too old, "
793 "or CONFIG_SYSFS_DEPRECATED) is unsupported, some "
794 "udev features may fail\n";
796 write(fd, depr_str, strlen(depr_str));
802 /* set signal handlers */
803 memset(&act, 0x00, sizeof(struct sigaction));
804 act.sa_handler = (void (*)(int)) sig_handler;
805 sigemptyset(&act.sa_mask);
806 act.sa_flags = SA_RESTART;
807 sigaction(SIGINT, &act, NULL);
808 sigaction(SIGTERM, &act, NULL);
809 sigaction(SIGCHLD, &act, NULL);
810 sigaction(SIGHUP, &act, NULL);
812 /* watch rules directory */
813 inotify_fd = inotify_init();
814 if (inotify_fd >= 0) {
815 if (udev_get_rules_path(udev) != NULL) {
816 inotify_add_watch(inotify_fd, udev_get_rules_path(udev),
817 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
819 char filename[UTIL_PATH_SIZE];
821 inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d",
822 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
823 inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d",
824 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
826 /* watch dynamic rules directory */
827 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
828 util_strlcat(filename, "/.udev/rules.d", sizeof(filename));
829 inotify_add_watch(inotify_fd, filename,
830 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
832 } else if (errno == ENOSYS)
833 err(udev, "the kernel does not support inotify, udevd can't monitor rules file changes\n");
835 err(udev, "inotify_init failed: %m\n");
837 /* in trace mode run one event after the other */
841 int memsize = mem_size_mb();
843 max_childs = 128 + (memsize / 4);
845 max_childs = UDEVD_MAX_CHILDS;
847 /* possibly overwrite maximum limit of executed events */
848 value = getenv("UDEVD_MAX_CHILDS");
850 max_childs = strtoul(value, NULL, 10);
851 info(udev, "initialize max_childs to %u\n", max_childs);
853 maxfd = udev_ctrl_get_fd(udev_ctrl);
854 maxfd = UDEV_MAX(maxfd, udev_monitor_get_fd(kernel_monitor));
855 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
856 maxfd = UDEV_MAX(maxfd, inotify_fd);
861 FD_SET(signal_pipe[READ_END], &readfds);
862 FD_SET(udev_ctrl_get_fd(udev_ctrl), &readfds);
863 FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
865 FD_SET(inotify_fd, &readfds);
866 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
869 err(udev, "error in select: %m\n");
873 /* get control message */
874 if (FD_ISSET(udev_ctrl_get_fd(udev_ctrl), &readfds))
875 handle_ctrl_msg(udev_ctrl);
877 /* get kernel uevent */
878 if (FD_ISSET(udev_monitor_get_fd(kernel_monitor), &readfds)) {
879 struct udev_device *dev;
881 dev = udev_monitor_receive_device(kernel_monitor);
883 struct udev_event *event;
885 event = udev_event_new(dev);
887 event_queue_insert(event);
889 udev_device_unref(dev);
893 /* received a signal, clear our notification pipe */
894 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
897 read(signal_pipe[READ_END], &buf, sizeof(buf));
900 /* rules directory inotify watch */
901 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
904 /* discard all possible events, we can just reload the config */
905 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
909 buf = malloc(nbytes);
911 err(udev, "error getting buffer for inotify, disable watching\n");
915 read(inotify_fd, buf, nbytes);
920 /* rules changed, set by inotify or a HUP signal */
922 struct udev_rules *rules_new;
925 rules_new = udev_rules_new(udev, 1);
926 if (rules_new != NULL) {
927 udev_rules_unref(rules);
932 if (sigchilds_waiting) {
933 sigchilds_waiting = 0;
940 event_queue_manager(udev);
946 udev_rules_unref(rules);
948 if (signal_pipe[READ_END] >= 0)
949 close(signal_pipe[READ_END]);
950 if (signal_pipe[WRITE_END] >= 0)
951 close(signal_pipe[WRITE_END]);
953 udev_ctrl_unref(udev_ctrl);
956 udev_monitor_unref(kernel_monitor);
958 udev_selinux_exit(udev);