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/>.
32 #include <sys/select.h>
34 #include <sys/types.h>
35 #include <sys/socket.h>
37 #include <sys/ioctl.h>
39 #include <sys/inotify.h>
43 #include "udev-rules.h"
45 #define UDEVD_PRIORITY -4
46 #define UDEV_PRIORITY -2
48 /* maximum limit of forked childs */
49 #define UDEVD_MAX_CHILDS 256
53 static void log_fn(struct udev *udev, int priority,
54 const char *file, int line, const char *fn,
55 const char *format, va_list args)
58 fprintf(stderr, "[%d] %s: ", (int) getpid(), fn);
59 vfprintf(stderr, format, args);
61 vsyslog(priority, format, args);
65 static int debug_trace;
66 static struct udev_rules rules;
67 static struct udev_ctrl *udev_ctrl;
68 static struct udev_monitor *kernel_monitor;
69 static int inotify_fd = -1;
71 static int signal_pipe[2] = {-1, -1};
72 static volatile int sigchilds_waiting;
73 static volatile int udev_exit;
74 static volatile int reload_config;
75 static int run_exec_q;
76 static int stop_exec_q;
77 static int max_childs;
79 static LIST_HEAD(exec_list);
80 static LIST_HEAD(running_list);
88 static void export_event_state(struct udev_event *event, enum event_state state)
90 char filename[UTIL_PATH_SIZE];
91 char filename_failed[UTIL_PATH_SIZE];
94 /* location of queue file */
95 snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu",
96 udev_get_dev_path(event->udev), udev_device_get_seqnum(event->dev));
98 /* location of failed file */
99 util_strlcpy(filename_failed, udev_get_dev_path(event->udev), sizeof(filename_failed));
100 util_strlcat(filename_failed, "/", sizeof(filename_failed));
101 start = util_strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed));
102 util_strlcat(filename_failed, udev_device_get_devpath(event->dev), sizeof(filename_failed));
103 util_path_encode(&filename_failed[start], sizeof(filename_failed) - start);
107 unlink(filename_failed);
108 delete_path(event->udev, filename_failed);
109 create_path(event->udev, filename);
110 udev_selinux_setfscreatecon(event->udev, filename, S_IFLNK);
111 symlink(udev_device_get_devpath(event->dev), filename);
112 udev_selinux_resetfscreatecon(event->udev);
115 if (udev_device_get_devpath_old(event->dev) != NULL) {
116 /* "move" event - rename failed file to current name, do not delete failed */
117 char filename_failed_old[UTIL_PATH_SIZE];
119 util_strlcpy(filename_failed_old, udev_get_dev_path(event->udev), sizeof(filename_failed_old));
120 util_strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
121 start = util_strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old));
122 util_strlcat(filename_failed_old, udev_device_get_devpath_old(event->dev), sizeof(filename_failed_old));
123 util_path_encode(&filename_failed_old[start], sizeof(filename) - start);
125 if (rename(filename_failed_old, filename_failed) == 0)
126 info(event->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
127 udev_device_get_devpath_old(event->dev), udev_device_get_devpath(event->dev));
129 unlink(filename_failed);
130 delete_path(event->udev, filename_failed);
134 delete_path(event->udev, filename);
137 /* move failed event to the failed directory */
138 create_path(event->udev, filename_failed);
139 rename(filename, filename_failed);
141 /* clean up possibly empty queue directory */
142 delete_path(event->udev, filename);
149 static void event_queue_delete(struct udev_event *event)
151 list_del(&event->node);
153 /* mark as failed, if "add" event returns non-zero */
154 if (event->exitstatus && strcmp(udev_device_get_action(event->dev), "add") == 0)
155 export_event_state(event, EVENT_FAILED);
157 export_event_state(event, EVENT_FINISHED);
159 udev_device_unref(event->dev);
160 udev_event_unref(event);
163 static void asmlinkage event_sig_handler(int signum)
165 if (signum == SIGALRM)
169 static void event_fork(struct udev_event *event)
172 struct sigaction act;
179 udev_monitor_unref(kernel_monitor);
180 udev_ctrl_unref(udev_ctrl);
183 close(signal_pipe[READ_END]);
184 close(signal_pipe[WRITE_END]);
186 logging_init("udevd-event");
187 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
189 /* set signal handlers */
190 memset(&act, 0x00, sizeof(act));
191 act.sa_handler = (void (*)(int)) event_sig_handler;
192 sigemptyset (&act.sa_mask);
194 sigaction(SIGALRM, &act, NULL);
196 /* reset to default */
197 act.sa_handler = SIG_DFL;
198 sigaction(SIGINT, &act, NULL);
199 sigaction(SIGTERM, &act, NULL);
200 sigaction(SIGCHLD, &act, NULL);
201 sigaction(SIGHUP, &act, NULL);
203 /* set timeout to prevent hanging processes */
204 alarm(UDEV_EVENT_TIMEOUT);
206 /* apply rules, create node, symlinks */
207 err = udev_event_run(event, &rules);
209 /* rules may change/disable the timeout */
210 if (udev_device_get_event_timeout(event->dev) >= 0)
211 alarm(udev_device_get_event_timeout(event->dev));
214 if (err == 0 && !event->ignore_device && udev_get_run(event->udev))
215 udev_rules_run(event);
216 info(event->udev, "seq %llu finished with %i\n", udev_device_get_seqnum(event->dev), err);
222 err(event->udev, "fork of child failed: %m\n");
223 event_queue_delete(event);
226 /* get SIGCHLD in main loop */
227 info(event->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
228 udev_device_get_seqnum(event->dev),
230 udev_device_get_action(event->dev),
231 udev_device_get_subsystem(event->dev),
232 time(NULL) - event->queue_time);
237 static void event_queue_insert(struct udev_event *event)
239 char filename[UTIL_PATH_SIZE];
242 event->queue_time = time(NULL);
244 export_event_state(event, EVENT_QUEUED);
245 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(event->dev), udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev));
247 util_strlcpy(filename, udev_get_dev_path(event->udev), sizeof(filename));
248 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
249 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
254 len = sprintf(str, "%llu\n", udev_device_get_seqnum(event->dev));
259 /* run one event after the other in debug mode */
261 list_add_tail(&event->node, &running_list);
263 waitpid(event->pid, NULL, 0);
264 event_queue_delete(event);
268 /* run all events with a timeout set immediately */
269 if (udev_device_get_timeout(event->dev) > 0) {
270 list_add_tail(&event->node, &running_list);
275 list_add_tail(&event->node, &exec_list);
279 static int mem_size_mb(void)
283 long int memsize = -1;
285 f = fopen("/proc/meminfo", "r");
289 while (fgets(buf, sizeof(buf), f) != NULL) {
292 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
293 memsize = value / 1024;
302 static int compare_devpath(const char *running, const char *waiting)
306 for (i = 0; i < UTIL_PATH_SIZE; i++) {
307 /* identical device event found */
308 if (running[i] == '\0' && waiting[i] == '\0')
311 /* parent device event found */
312 if (running[i] == '\0' && waiting[i] == '/')
315 /* child device event found */
316 if (running[i] == '/' && waiting[i] == '\0')
319 /* no matching event */
320 if (running[i] != waiting[i])
327 /* lookup event for identical, parent, child, or physical device */
328 static int devpath_busy(struct udev_event *event, int limit)
330 struct udev_event *loop_event;
331 int childs_count = 0;
333 /* check exec-queue which may still contain delayed events we depend on */
334 list_for_each_entry(loop_event, &exec_list, node) {
335 /* skip ourself and all later events */
336 if (udev_device_get_seqnum(loop_event->dev) >= udev_device_get_seqnum(event->dev))
339 /* check our old name */
340 if (udev_device_get_devpath_old(event->dev) != NULL)
341 if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0)
344 /* check identical, parent, or child device event */
345 if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) {
346 dbg(event->udev, "%llu, device event still pending %llu (%s)\n",
347 udev_device_get_seqnum(event->dev),
348 udev_device_get_seqnum(loop_event->dev),
349 udev_device_get_devpath(loop_event->dev));
353 /* check for our major:minor number */
354 if (major(udev_device_get_devnum(event->dev)) > 0 &&
355 udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) &&
356 strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) {
357 dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n",
358 udev_device_get_seqnum(event->dev),
359 udev_device_get_seqnum(loop_event->dev),
360 major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev)));
364 /* check physical device event (special case of parent) */
365 if (udev_device_get_physdevpath(event->dev) != NULL &&
366 strcmp(udev_device_get_action(event->dev), "add") == 0)
367 if (compare_devpath(udev_device_get_devpath(loop_event->dev),
368 udev_device_get_physdevpath(event->dev)) != 0) {
369 dbg(event->udev, "%llu, physical device event still pending %llu (%s)\n",
370 udev_device_get_seqnum(event->dev),
371 udev_device_get_seqnum(loop_event->dev),
372 udev_device_get_devpath(loop_event->dev));
377 /* check run queue for still running events */
378 list_for_each_entry(loop_event, &running_list, node) {
381 if (childs_count++ >= limit) {
382 info(event->udev, "%llu, maximum number (%i) of childs reached\n",
383 udev_device_get_seqnum(event->dev), childs_count);
387 /* check our old name */
388 if (udev_device_get_devpath_old(event->dev) != NULL)
389 if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0)
392 /* check identical, parent, or child device event */
393 if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) {
394 dbg(event->udev, "%llu, device event still running %llu (%s)\n",
395 udev_device_get_seqnum(event->dev),
396 udev_device_get_seqnum(loop_event->dev),
397 udev_device_get_devpath(loop_event->dev));
401 /* check for our major:minor number */
402 if (major(udev_device_get_devnum(event->dev)) > 0 &&
403 udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) &&
404 strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) {
405 dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n",
406 udev_device_get_seqnum(event->dev),
407 udev_device_get_seqnum(loop_event->dev),
408 major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev)));
412 /* check physical device event (special case of parent) */
413 if (udev_device_get_physdevpath(event->dev) != NULL &&
414 strcmp(udev_device_get_action(event->dev), "add") == 0)
415 if (compare_devpath(udev_device_get_devpath(loop_event->dev),
416 udev_device_get_physdevpath(event->dev)) != 0) {
417 dbg(event->udev, "%llu, physical device event still pending %llu (%s)\n",
418 udev_device_get_seqnum(event->dev),
419 udev_device_get_seqnum(loop_event->dev),
420 udev_device_get_devpath(loop_event->dev));
427 /* serializes events for the identical and parent and child devices */
428 static void event_queue_manager(struct udev *udev)
430 struct udev_event *loop_event;
431 struct udev_event *tmp_event;
433 if (list_empty(&exec_list))
436 list_for_each_entry_safe(loop_event, tmp_event, &exec_list, node) {
437 /* serialize and wait for parent or child events */
438 if (devpath_busy(loop_event, max_childs) != 0) {
439 dbg(udev, "delay seq %llu (%s)\n",
440 udev_device_get_seqnum(loop_event->dev),
441 udev_device_get_devpath(loop_event->dev));
445 /* move event to run list */
446 list_move_tail(&loop_event->node, &running_list);
447 event_fork(loop_event);
448 dbg(udev, "moved seq %llu to running list\n", udev_device_get_seqnum(loop_event->dev));
452 /* receive the udevd message from userspace */
453 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
455 struct udev *udev = udev_ctrl_get_udev(uctrl);
456 struct udev_ctrl_msg *ctrl_msg;
460 ctrl_msg = udev_ctrl_receive_msg(uctrl);
461 if (ctrl_msg == NULL)
464 i = udev_ctrl_get_set_log_level(ctrl_msg);
466 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
467 udev_set_log_priority(udev, i);
470 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
471 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
475 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
476 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
478 event_queue_manager(udev);
481 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
482 info(udev, "udevd message (RELOAD_RULES) received\n");
486 str = udev_ctrl_get_set_env(ctrl_msg);
494 val = strchr(key, '=');
498 if (val[0] == '\0') {
499 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
500 udev_add_property(udev, key, NULL);
502 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
503 udev_add_property(udev, key, val);
506 err(udev, "wrong key format '%s'\n", key);
512 i = udev_ctrl_get_set_max_childs(ctrl_msg);
514 info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
518 udev_ctrl_msg_unref(ctrl_msg);
521 static void asmlinkage sig_handler(int signum)
529 /* set flag, then write to pipe if needed */
530 sigchilds_waiting = 1;
537 /* write to pipe, which will wakeup select() in our mainloop */
538 write(signal_pipe[WRITE_END], "", 1);
541 static void udev_done(int pid, int exitstatus)
543 /* find event associated with pid and delete it */
544 struct udev_event *event;
546 list_for_each_entry(event, &running_list, node) {
547 if (event->pid == pid) {
548 info(event->udev, "seq %llu, pid [%d] exit with %i, %ld seconds old\n",
549 udev_device_get_seqnum(event->dev), event->pid,
550 exitstatus, time(NULL) - event->queue_time);
551 event->exitstatus = exitstatus;
552 event_queue_delete(event);
554 /* there may be events waiting with the same devpath */
561 static void reap_sigchilds(void)
567 pid = waitpid(-1, &status, WNOHANG);
570 if (WIFEXITED(status))
571 status = WEXITSTATUS(status);
572 else if (WIFSIGNALED(status))
573 status = WTERMSIG(status) + 128;
576 udev_done(pid, status);
580 static void export_initial_seqnum(struct udev *udev)
582 char filename[UTIL_PATH_SIZE];
587 util_strlcpy(filename, udev_get_sys_path(udev), sizeof(filename));
588 util_strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
589 fd = open(filename, O_RDONLY);
591 len = read(fd, seqnum, sizeof(seqnum)-1);
595 strcpy(seqnum, "0\n");
598 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
599 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
600 create_path(udev, filename);
601 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
603 write(fd, seqnum, len);
608 int main(int argc, char *argv[])
613 struct sigaction act;
617 static const struct option options[] = {
618 { "daemon", no_argument, NULL, 'd' },
619 { "debug-trace", no_argument, NULL, 't' },
620 { "debug", no_argument, NULL, 'D' },
621 { "help", no_argument, NULL, 'h' },
622 { "version", no_argument, NULL, 'V' },
632 logging_init("udevd");
633 udev_set_log_fn(udev, log_fn);
634 info(udev, "version %s\n", VERSION);
640 option = getopt_long(argc, argv, "dDthV", options, NULL);
653 if (udev_get_log_priority(udev) < LOG_INFO)
654 udev_set_log_priority(udev, LOG_INFO);
657 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
660 printf("%s\n", VERSION);
668 fprintf(stderr, "root privileges required\n");
669 err(udev, "root privileges required\n");
673 /* make sure std{in,out,err} fd's are in a sane state */
674 fd = open("/dev/null", O_RDWR);
676 fprintf(stderr, "cannot open /dev/null\n");
677 err(udev, "cannot open /dev/null\n");
679 if (fd > STDIN_FILENO)
680 dup2(fd, STDIN_FILENO);
681 if (write(STDOUT_FILENO, 0, 0) < 0)
682 dup2(fd, STDOUT_FILENO);
683 if (write(STDERR_FILENO, 0, 0) < 0)
684 dup2(fd, STDERR_FILENO);
686 /* init control socket, bind() ensures, that only one udevd instance is running */
687 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
688 if (udev_ctrl == NULL) {
689 fprintf(stderr, "error initializing control socket");
690 err(udev, "error initializing udevd socket");
695 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
696 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
697 err(udev, "error binding control socket, seems udevd is already running\n");
702 kernel_monitor = udev_monitor_new_from_netlink(udev);
703 if (kernel_monitor == NULL || udev_monitor_enable_receiving(kernel_monitor) < 0) {
704 fprintf(stderr, "error initializing netlink socket\n");
705 err(udev, "error initializing netlink socket\n");
709 /* set receive buffersize */
710 const int buffersize = 32 * 1024 * 1024;
712 setsockopt(udev_monitor_get_fd(kernel_monitor),
713 SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
716 err = pipe(signal_pipe);
718 err(udev, "error getting pipes: %m\n");
722 err = fcntl(signal_pipe[READ_END], F_GETFL, 0);
724 err(udev, "error fcntl on read pipe: %m\n");
727 err = fcntl(signal_pipe[READ_END], F_SETFL, err | O_NONBLOCK);
729 err(udev, "error fcntl on read pipe: %m\n");
733 err = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
735 err(udev, "error fcntl on write pipe: %m\n");
738 err = fcntl(signal_pipe[WRITE_END], F_SETFL, err | O_NONBLOCK);
740 err(udev, "error fcntl on write pipe: %m\n");
744 udev_rules_init(udev, &rules, 1);
745 export_initial_seqnum(udev);
753 dbg(udev, "daemonized fork running\n");
756 err(udev, "fork of daemon failed: %m\n");
760 dbg(udev, "child [%u] running, parent exits\n", pid);
766 /* redirect std{out,err} */
768 dup2(fd, STDOUT_FILENO);
769 dup2(fd, STDERR_FILENO);
771 if (fd > STDERR_FILENO)
774 /* set scheduling priority for the daemon */
775 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
781 /* OOM_DISABLE == -17 */
782 fd = open("/proc/self/oom_adj", O_RDWR);
784 err(udev, "error disabling OOM: %m\n");
790 fd = open("/dev/kmsg", O_WRONLY);
792 const char *ver_str = "<6>udev: starting version " VERSION "\n";
793 char path[UTIL_PATH_SIZE];
796 write(fd, ver_str, strlen(ver_str));
797 util_strlcpy(path, udev_get_sys_path(udev), sizeof(path));
798 util_strlcat(path, "/class/mem/null", sizeof(path));
799 if (lstat(path, &statbuf) == 0) {
800 if (S_ISDIR(statbuf.st_mode)) {
801 const char *depr_str = "<6>udev: deprecated sysfs layout (kernel too old, "
802 "or CONFIG_SYSFS_DEPRECATED) is unsupported, some "
803 "udev features may fail\n";
805 write(fd, depr_str, strlen(depr_str));
811 /* set signal handlers */
812 memset(&act, 0x00, sizeof(struct sigaction));
813 act.sa_handler = (void (*)(int)) sig_handler;
814 sigemptyset(&act.sa_mask);
815 act.sa_flags = SA_RESTART;
816 sigaction(SIGINT, &act, NULL);
817 sigaction(SIGTERM, &act, NULL);
818 sigaction(SIGCHLD, &act, NULL);
819 sigaction(SIGHUP, &act, NULL);
821 /* watch rules directory */
822 inotify_fd = inotify_init();
823 if (inotify_fd >= 0) {
824 if (udev_get_rules_path(udev) != NULL) {
825 inotify_add_watch(inotify_fd, udev_get_rules_path(udev),
826 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
828 char filename[PATH_MAX];
830 inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d",
831 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
832 inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d",
833 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
835 /* watch dynamic rules directory */
836 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
837 util_strlcat(filename, "/.udev/rules.d", sizeof(filename));
838 inotify_add_watch(inotify_fd, filename,
839 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
841 } else if (errno == ENOSYS)
842 err(udev, "the kernel does not support inotify, udevd can't monitor rules file changes\n");
844 err(udev, "inotify_init failed: %m\n");
846 /* maximum limit of forked childs */
847 value = getenv("UDEVD_MAX_CHILDS");
849 max_childs = strtoul(value, NULL, 10);
851 int memsize = mem_size_mb();
853 max_childs = 128 + (memsize / 4);
855 max_childs = UDEVD_MAX_CHILDS;
857 info(udev, "initialize max_childs to %u\n", max_childs);
859 maxfd = udev_ctrl_get_fd(udev_ctrl);
860 maxfd = UDEV_MAX(maxfd, udev_monitor_get_fd(kernel_monitor));
861 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
862 maxfd = UDEV_MAX(maxfd, inotify_fd);
868 FD_SET(signal_pipe[READ_END], &readfds);
869 FD_SET(udev_ctrl_get_fd(udev_ctrl), &readfds);
870 FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
872 FD_SET(inotify_fd, &readfds);
874 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
877 err(udev, "error in select: %m\n");
881 /* get control message */
882 if (FD_ISSET(udev_ctrl_get_fd(udev_ctrl), &readfds))
883 handle_ctrl_msg(udev_ctrl);
885 /* get kernel uevent */
886 if (FD_ISSET(udev_monitor_get_fd(kernel_monitor), &readfds)) {
887 struct udev_device *dev;
889 dev = udev_monitor_receive_device(kernel_monitor);
891 struct udev_event *event;
893 event = udev_event_new(dev);
895 event_queue_insert(event);
897 udev_device_unref(dev);
901 /* received a signal, clear our notification pipe */
902 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
905 read(signal_pipe[READ_END], &buf, sizeof(buf));
908 /* rules directory inotify watch */
909 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
912 /* discard all possible events, we can just reload the config */
913 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
917 buf = malloc(nbytes);
919 err(udev, "error getting buffer for inotify, disable watching\n");
923 read(inotify_fd, buf, nbytes);
928 /* rules changed, set by inotify or a HUP signal */
931 udev_rules_cleanup(&rules);
932 udev_rules_init(udev, &rules, 1);
935 if (sigchilds_waiting) {
936 sigchilds_waiting = 0;
943 event_queue_manager(udev);
949 udev_rules_cleanup(&rules);
951 if (signal_pipe[READ_END] >= 0)
952 close(signal_pipe[READ_END]);
953 if (signal_pipe[WRITE_END] >= 0)
954 close(signal_pipe[WRITE_END]);
956 udev_ctrl_unref(udev_ctrl);
959 udev_monitor_unref(kernel_monitor);