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;
66 static int signal_pipe[2] = {-1, -1};
67 static volatile int sigchilds_waiting;
68 static volatile int udev_exit;
69 static volatile int reload_config;
70 static int run_exec_q;
71 static int stop_exec_q;
72 static int max_childs;
74 static struct udev_list_node exec_list;
75 static struct udev_list_node running_list;
83 static struct udev_event *node_to_event(struct udev_list_node *node)
88 event -= offsetof(struct udev_event, node);
89 return (struct udev_event *)event;
92 static void export_event_state(struct udev_event *event, enum event_state state)
94 char filename[UTIL_PATH_SIZE];
95 char filename_failed[UTIL_PATH_SIZE];
98 /* location of queue file */
99 snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu",
100 udev_get_dev_path(event->udev), udev_device_get_seqnum(event->dev));
102 /* location of failed file */
103 util_strlcpy(filename_failed, udev_get_dev_path(event->udev), sizeof(filename_failed));
104 util_strlcat(filename_failed, "/", sizeof(filename_failed));
105 start = util_strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed));
106 util_strlcat(filename_failed, udev_device_get_devpath(event->dev), sizeof(filename_failed));
107 util_path_encode(&filename_failed[start], sizeof(filename_failed) - start);
111 if(unlink(filename_failed) == 0)
112 util_delete_path(event->udev, filename_failed);
113 util_create_path(event->udev, filename);
114 udev_selinux_setfscreatecon(event->udev, filename, S_IFLNK);
115 symlink(udev_device_get_devpath(event->dev), filename);
116 udev_selinux_resetfscreatecon(event->udev);
119 if (udev_device_get_devpath_old(event->dev) != NULL) {
120 /* "move" event - rename failed file to current name, do not delete failed */
121 char filename_failed_old[UTIL_PATH_SIZE];
123 util_strlcpy(filename_failed_old, udev_get_dev_path(event->udev), sizeof(filename_failed_old));
124 util_strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
125 start = util_strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old));
126 util_strlcat(filename_failed_old, udev_device_get_devpath_old(event->dev), sizeof(filename_failed_old));
127 util_path_encode(&filename_failed_old[start], sizeof(filename) - start);
129 if (rename(filename_failed_old, filename_failed) == 0)
130 info(event->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
131 udev_device_get_devpath_old(event->dev), udev_device_get_devpath(event->dev));
133 if (unlink(filename_failed) == 0)
134 util_delete_path(event->udev, filename_failed);
139 /* clean up possibly empty queue directory */
140 if (udev_list_is_empty(&exec_list) && udev_list_is_empty(&running_list))
141 util_delete_path(event->udev, filename);
144 /* move failed event to the failed directory */
145 util_create_path(event->udev, filename_failed);
146 rename(filename, filename_failed);
148 /* clean up possibly empty queue directory */
149 if (udev_list_is_empty(&exec_list) && udev_list_is_empty(&running_list))
150 util_delete_path(event->udev, filename);
157 static void event_queue_delete(struct udev_event *event)
159 udev_list_node_remove(&event->node);
161 /* mark as failed, if "add" event returns non-zero */
162 if (event->exitstatus && strcmp(udev_device_get_action(event->dev), "add") == 0)
163 export_event_state(event, EVENT_FAILED);
165 export_event_state(event, EVENT_FINISHED);
167 udev_device_unref(event->dev);
168 udev_event_unref(event);
171 static void asmlinkage event_sig_handler(int signum)
173 if (signum == SIGALRM)
177 static void event_fork(struct udev_event *event)
180 struct sigaction act;
187 udev_monitor_unref(kernel_monitor);
188 udev_ctrl_unref(udev_ctrl);
191 close(signal_pipe[READ_END]);
192 close(signal_pipe[WRITE_END]);
194 logging_init("udevd-event");
195 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
197 /* set signal handlers */
198 memset(&act, 0x00, sizeof(act));
199 act.sa_handler = (void (*)(int)) event_sig_handler;
200 sigemptyset (&act.sa_mask);
202 sigaction(SIGALRM, &act, NULL);
204 /* reset to default */
205 act.sa_handler = SIG_DFL;
206 sigaction(SIGINT, &act, NULL);
207 sigaction(SIGTERM, &act, NULL);
208 sigaction(SIGCHLD, &act, NULL);
209 sigaction(SIGHUP, &act, NULL);
211 /* set timeout to prevent hanging processes */
212 alarm(UDEV_EVENT_TIMEOUT);
214 /* apply rules, create node, symlinks */
215 err = udev_event_execute_rules(event, rules);
217 /* rules may change/disable the timeout */
218 if (udev_device_get_event_timeout(event->dev) >= 0)
219 alarm(udev_device_get_event_timeout(event->dev));
222 if (err == 0 && !event->ignore_device && udev_get_run(event->udev))
223 udev_event_execute_run(event);
224 info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err);
230 err(event->udev, "fork of child failed: %m\n");
231 event_queue_delete(event);
234 /* get SIGCHLD in main loop */
235 info(event->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
236 udev_device_get_seqnum(event->dev),
238 udev_device_get_action(event->dev),
239 udev_device_get_subsystem(event->dev),
240 time(NULL) - event->queue_time);
245 static void event_queue_insert(struct udev_event *event)
247 char filename[UTIL_PATH_SIZE];
250 event->queue_time = time(NULL);
252 export_event_state(event, EVENT_QUEUED);
253 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(event->dev),
254 udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev));
256 util_strlcpy(filename, udev_get_dev_path(event->udev), sizeof(filename));
257 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
258 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
263 len = sprintf(str, "%llu\n", udev_device_get_seqnum(event->dev));
268 /* run one event after the other in debug mode */
270 udev_list_node_append(&event->node, &running_list);
272 waitpid(event->pid, NULL, 0);
273 event_queue_delete(event);
277 /* run all events with a timeout set immediately */
278 if (udev_device_get_timeout(event->dev) > 0) {
279 udev_list_node_append(&event->node, &running_list);
284 udev_list_node_append(&event->node, &exec_list);
288 static int mem_size_mb(void)
292 long int memsize = -1;
294 f = fopen("/proc/meminfo", "r");
298 while (fgets(buf, sizeof(buf), f) != NULL) {
301 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
302 memsize = value / 1024;
311 static int compare_devpath(const char *running, const char *waiting)
315 for (i = 0; i < UTIL_PATH_SIZE; 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 */
329 if (running[i] != waiting[i])
336 /* lookup event for identical, parent, child, or physical device */
337 static int devpath_busy(struct udev_event *event, int limit)
339 struct udev_list_node *loop;
340 int childs_count = 0;
342 /* check exec-queue which may still contain delayed events we depend on */
343 udev_list_node_foreach(loop, &exec_list) {
344 struct udev_event *loop_event = node_to_event(loop);
346 /* skip ourself and all later events */
347 if (udev_device_get_seqnum(loop_event->dev) >= udev_device_get_seqnum(event->dev))
350 /* check our old name */
351 if (udev_device_get_devpath_old(event->dev) != NULL)
352 if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0)
355 /* check identical, parent, or child device event */
356 if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) {
357 dbg(event->udev, "%llu, device event still pending %llu (%s)\n",
358 udev_device_get_seqnum(event->dev),
359 udev_device_get_seqnum(loop_event->dev),
360 udev_device_get_devpath(loop_event->dev));
364 /* check for our major:minor number */
365 if (major(udev_device_get_devnum(event->dev)) > 0 &&
366 udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) &&
367 strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) {
368 dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n",
369 udev_device_get_seqnum(event->dev),
370 udev_device_get_seqnum(loop_event->dev),
371 major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev)));
375 /* check physical device event (special case of parent) */
376 if (udev_device_get_physdevpath(event->dev) != NULL &&
377 strcmp(udev_device_get_action(event->dev), "add") == 0)
378 if (compare_devpath(udev_device_get_devpath(loop_event->dev),
379 udev_device_get_physdevpath(event->dev)) != 0) {
380 dbg(event->udev, "%llu, physical device event still pending %llu (%s)\n",
381 udev_device_get_seqnum(event->dev),
382 udev_device_get_seqnum(loop_event->dev),
383 udev_device_get_devpath(loop_event->dev));
388 /* check run queue for still running events */
389 udev_list_node_foreach(loop, &running_list) {
390 struct udev_event *loop_event = node_to_event(loop);
392 if (childs_count++ >= limit) {
393 info(event->udev, "%llu, maximum number (%i) of childs reached\n",
394 udev_device_get_seqnum(event->dev), childs_count);
398 /* check our old name */
399 if (udev_device_get_devpath_old(event->dev) != NULL)
400 if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0)
403 /* check identical, parent, or child device event */
404 if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) {
405 dbg(event->udev, "%llu, device event still running %llu (%s)\n",
406 udev_device_get_seqnum(event->dev),
407 udev_device_get_seqnum(loop_event->dev),
408 udev_device_get_devpath(loop_event->dev));
412 /* check for our major:minor number */
413 if (major(udev_device_get_devnum(event->dev)) > 0 &&
414 udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) &&
415 strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) {
416 dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n",
417 udev_device_get_seqnum(event->dev),
418 udev_device_get_seqnum(loop_event->dev),
419 major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev)));
423 /* check physical device event (special case of parent) */
424 if (udev_device_get_physdevpath(event->dev) != NULL &&
425 strcmp(udev_device_get_action(event->dev), "add") == 0)
426 if (compare_devpath(udev_device_get_devpath(loop_event->dev),
427 udev_device_get_physdevpath(event->dev)) != 0) {
428 dbg(event->udev, "%llu, physical device event still pending %llu (%s)\n",
429 udev_device_get_seqnum(event->dev),
430 udev_device_get_seqnum(loop_event->dev),
431 udev_device_get_devpath(loop_event->dev));
438 /* serializes events for the identical and parent and child devices */
439 static void event_queue_manager(struct udev *udev)
441 struct udev_list_node *loop;
442 struct udev_list_node *tmp;
444 if (udev_list_is_empty(&exec_list))
447 udev_list_node_foreach_safe(loop, tmp, &exec_list) {
448 struct udev_event *loop_event = node_to_event(loop);
450 /* serialize and wait for parent or child events */
451 if (devpath_busy(loop_event, max_childs) != 0) {
452 dbg(udev, "delay seq %llu (%s)\n",
453 udev_device_get_seqnum(loop_event->dev),
454 udev_device_get_devpath(loop_event->dev));
458 /* move event to run list */
459 udev_list_node_remove(&loop_event->node);
460 udev_list_node_append(&loop_event->node, &running_list);
461 event_fork(loop_event);
462 dbg(udev, "moved seq %llu to running list\n", udev_device_get_seqnum(loop_event->dev));
466 /* receive the udevd message from userspace */
467 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
469 struct udev *udev = udev_ctrl_get_udev(uctrl);
470 struct udev_ctrl_msg *ctrl_msg;
474 ctrl_msg = udev_ctrl_receive_msg(uctrl);
475 if (ctrl_msg == NULL)
478 i = udev_ctrl_get_set_log_level(ctrl_msg);
480 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
481 udev_set_log_priority(udev, i);
484 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
485 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
489 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
490 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
492 event_queue_manager(udev);
495 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
496 info(udev, "udevd message (RELOAD_RULES) received\n");
500 str = udev_ctrl_get_set_env(ctrl_msg);
508 val = strchr(key, '=');
512 if (val[0] == '\0') {
513 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
514 udev_add_property(udev, key, NULL);
516 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
517 udev_add_property(udev, key, val);
520 err(udev, "wrong key format '%s'\n", key);
526 i = udev_ctrl_get_set_max_childs(ctrl_msg);
528 info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
532 udev_ctrl_msg_unref(ctrl_msg);
535 static void asmlinkage sig_handler(int signum)
543 /* set flag, then write to pipe if needed */
544 sigchilds_waiting = 1;
551 /* write to pipe, which will wakeup select() in our mainloop */
552 write(signal_pipe[WRITE_END], "", 1);
555 static void udev_done(int pid, int exitstatus)
557 struct udev_list_node *loop;
559 /* find event associated with pid and delete it */
560 udev_list_node_foreach(loop, &running_list) {
561 struct udev_event *loop_event = node_to_event(loop);
563 if (loop_event->pid == pid) {
564 info(loop_event->udev, "seq %llu cleanup, pid [%d], status %i, %ld seconds old\n",
565 udev_device_get_seqnum(loop_event->dev), loop_event->pid,
566 exitstatus, time(NULL) - loop_event->queue_time);
567 loop_event->exitstatus = exitstatus;
568 event_queue_delete(loop_event);
570 /* there may be events waiting with the same devpath */
577 static void reap_sigchilds(void)
583 pid = waitpid(-1, &status, WNOHANG);
586 if (WIFEXITED(status))
587 status = WEXITSTATUS(status);
588 else if (WIFSIGNALED(status))
589 status = WTERMSIG(status) + 128;
592 udev_done(pid, status);
596 static void export_initial_seqnum(struct udev *udev)
598 char filename[UTIL_PATH_SIZE];
603 util_strlcpy(filename, udev_get_sys_path(udev), sizeof(filename));
604 util_strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
605 fd = open(filename, O_RDONLY);
607 len = read(fd, seqnum, sizeof(seqnum)-1);
611 strcpy(seqnum, "0\n");
614 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
615 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
616 util_create_path(udev, filename);
617 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
619 write(fd, seqnum, len);
624 int main(int argc, char *argv[])
629 struct sigaction act;
633 static const struct option options[] = {
634 { "daemon", no_argument, NULL, 'd' },
635 { "debug-trace", no_argument, NULL, 't' },
636 { "debug", no_argument, NULL, 'D' },
637 { "help", no_argument, NULL, 'h' },
638 { "version", no_argument, NULL, 'V' },
648 logging_init("udevd");
649 udev_set_log_fn(udev, log_fn);
650 info(udev, "version %s\n", VERSION);
651 udev_selinux_init(udev);
656 option = getopt_long(argc, argv, "dDthV", options, NULL);
669 if (udev_get_log_priority(udev) < LOG_INFO)
670 udev_set_log_priority(udev, LOG_INFO);
673 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
676 printf("%s\n", VERSION);
684 fprintf(stderr, "root privileges required\n");
685 err(udev, "root privileges required\n");
689 /* make sure std{in,out,err} fd's are in a sane state */
690 fd = open("/dev/null", O_RDWR);
692 fprintf(stderr, "cannot open /dev/null\n");
693 err(udev, "cannot open /dev/null\n");
695 if (fd > STDIN_FILENO)
696 dup2(fd, STDIN_FILENO);
697 if (write(STDOUT_FILENO, 0, 0) < 0)
698 dup2(fd, STDOUT_FILENO);
699 if (write(STDERR_FILENO, 0, 0) < 0)
700 dup2(fd, STDERR_FILENO);
702 /* init control socket, bind() ensures, that only one udevd instance is running */
703 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
704 if (udev_ctrl == NULL) {
705 fprintf(stderr, "error initializing control socket");
706 err(udev, "error initializing udevd socket");
711 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
712 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
713 err(udev, "error binding control socket, seems udevd is already running\n");
718 kernel_monitor = udev_monitor_new_from_netlink(udev);
719 if (kernel_monitor == NULL || udev_monitor_enable_receiving(kernel_monitor) < 0) {
720 fprintf(stderr, "error initializing netlink socket\n");
721 err(udev, "error initializing netlink socket\n");
725 udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
727 err = pipe(signal_pipe);
729 err(udev, "error getting pipes: %m\n");
733 err = fcntl(signal_pipe[READ_END], F_GETFL, 0);
735 err(udev, "error fcntl on read pipe: %m\n");
738 err = fcntl(signal_pipe[READ_END], F_SETFL, err | O_NONBLOCK);
740 err(udev, "error fcntl on read pipe: %m\n");
744 err = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
746 err(udev, "error fcntl on write pipe: %m\n");
749 err = fcntl(signal_pipe[WRITE_END], F_SETFL, err | O_NONBLOCK);
751 err(udev, "error fcntl on write pipe: %m\n");
755 rules = udev_rules_new(udev, 1);
757 err(udev, "error reading rules\n");
760 udev_list_init(&running_list);
761 udev_list_init(&exec_list);
762 export_initial_seqnum(udev);
770 dbg(udev, "daemonized fork running\n");
773 err(udev, "fork of daemon failed: %m\n");
777 dbg(udev, "child [%u] running, parent exits\n", pid);
783 /* redirect std{out,err} */
785 dup2(fd, STDOUT_FILENO);
786 dup2(fd, STDERR_FILENO);
788 if (fd > STDERR_FILENO)
791 /* set scheduling priority for the daemon */
792 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
798 /* OOM_DISABLE == -17 */
799 fd = open("/proc/self/oom_adj", O_RDWR);
801 err(udev, "error disabling OOM: %m\n");
807 fd = open("/dev/kmsg", O_WRONLY);
809 const char *ver_str = "<6>udev: starting version " VERSION "\n";
810 char path[UTIL_PATH_SIZE];
813 write(fd, ver_str, strlen(ver_str));
814 util_strlcpy(path, udev_get_sys_path(udev), sizeof(path));
815 util_strlcat(path, "/class/mem/null", sizeof(path));
816 if (lstat(path, &statbuf) == 0) {
817 if (S_ISDIR(statbuf.st_mode)) {
818 const char *depr_str = "<6>udev: deprecated sysfs layout (kernel too old, "
819 "or CONFIG_SYSFS_DEPRECATED) is unsupported, some "
820 "udev features may fail\n";
822 write(fd, depr_str, strlen(depr_str));
828 /* set signal handlers */
829 memset(&act, 0x00, sizeof(struct sigaction));
830 act.sa_handler = (void (*)(int)) sig_handler;
831 sigemptyset(&act.sa_mask);
832 act.sa_flags = SA_RESTART;
833 sigaction(SIGINT, &act, NULL);
834 sigaction(SIGTERM, &act, NULL);
835 sigaction(SIGCHLD, &act, NULL);
836 sigaction(SIGHUP, &act, NULL);
838 /* watch rules directory */
839 inotify_fd = inotify_init();
840 if (inotify_fd >= 0) {
841 if (udev_get_rules_path(udev) != NULL) {
842 inotify_add_watch(inotify_fd, udev_get_rules_path(udev),
843 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
845 char filename[PATH_MAX];
847 inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d",
848 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
849 inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d",
850 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
852 /* watch dynamic rules directory */
853 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
854 util_strlcat(filename, "/.udev/rules.d", sizeof(filename));
855 inotify_add_watch(inotify_fd, filename,
856 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
858 } else if (errno == ENOSYS)
859 err(udev, "the kernel does not support inotify, udevd can't monitor rules file changes\n");
861 err(udev, "inotify_init failed: %m\n");
863 /* maximum limit of forked childs */
864 value = getenv("UDEVD_MAX_CHILDS");
866 max_childs = strtoul(value, NULL, 10);
868 int memsize = mem_size_mb();
870 max_childs = 128 + (memsize / 4);
872 max_childs = UDEVD_MAX_CHILDS;
874 info(udev, "initialize max_childs to %u\n", max_childs);
876 maxfd = udev_ctrl_get_fd(udev_ctrl);
877 maxfd = UDEV_MAX(maxfd, udev_monitor_get_fd(kernel_monitor));
878 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
879 maxfd = UDEV_MAX(maxfd, inotify_fd);
884 FD_SET(signal_pipe[READ_END], &readfds);
885 FD_SET(udev_ctrl_get_fd(udev_ctrl), &readfds);
886 FD_SET(udev_monitor_get_fd(kernel_monitor), &readfds);
888 FD_SET(inotify_fd, &readfds);
889 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
892 err(udev, "error in select: %m\n");
896 /* get control message */
897 if (FD_ISSET(udev_ctrl_get_fd(udev_ctrl), &readfds))
898 handle_ctrl_msg(udev_ctrl);
900 /* get kernel uevent */
901 if (FD_ISSET(udev_monitor_get_fd(kernel_monitor), &readfds)) {
902 struct udev_device *dev;
904 dev = udev_monitor_receive_device(kernel_monitor);
906 struct udev_event *event;
908 event = udev_event_new(dev);
910 event_queue_insert(event);
912 udev_device_unref(dev);
916 /* received a signal, clear our notification pipe */
917 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
920 read(signal_pipe[READ_END], &buf, sizeof(buf));
923 /* rules directory inotify watch */
924 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
927 /* discard all possible events, we can just reload the config */
928 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
932 buf = malloc(nbytes);
934 err(udev, "error getting buffer for inotify, disable watching\n");
938 read(inotify_fd, buf, nbytes);
943 /* rules changed, set by inotify or a HUP signal */
945 struct udev_rules *rules_new;
948 rules_new = udev_rules_new(udev, 1);
949 if (rules_new != NULL) {
950 udev_rules_unref(rules);
955 if (sigchilds_waiting) {
956 sigchilds_waiting = 0;
963 event_queue_manager(udev);
969 udev_rules_unref(rules);
971 if (signal_pipe[READ_END] >= 0)
972 close(signal_pipe[READ_END]);
973 if (signal_pipe[WRITE_END] >= 0)
974 close(signal_pipe[WRITE_END]);
976 udev_ctrl_unref(udev_ctrl);
979 udev_monitor_unref(kernel_monitor);
981 udev_selinux_exit(udev);