2 * Copyright (C) 2004-2009 Kay Sievers <kay.sievers@vrfy.org>
3 * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
4 * Copyright (C) 2009 Canonical Ltd.
5 * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
35 #include <sys/prctl.h>
36 #include <sys/socket.h>
37 #include <sys/signalfd.h>
38 #include <sys/select.h>
42 #include <sys/ioctl.h>
43 #include <sys/inotify.h>
47 #define UDEVD_PRIORITY -4
48 #define UDEV_PRIORITY -2
52 static void log_fn(struct udev *udev, int priority,
53 const char *file, int line, const char *fn,
54 const char *format, va_list args)
61 vsnprintf(buf, sizeof(buf), format, args);
62 gettimeofday(&tv, &tz);
63 fprintf(stderr, "%llu.%06u [%u] %s: %s",
64 (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec,
65 (int) getpid(), fn, buf);
67 vsyslog(priority, format, args);
71 static bool debug_trace;
72 static struct udev_rules *rules;
73 static struct udev_queue_export *udev_queue_export;
74 static struct udev_ctrl *udev_ctrl;
75 static struct udev_monitor *monitor;
76 static int worker_watch[2];
77 static pid_t settle_pid;
78 static bool stop_exec_queue;
79 static bool reload_config;
80 static int max_childs;
82 static sigset_t orig_sigmask;
83 static struct udev_list_node event_list;
84 static struct udev_list_node worker_list;
85 static bool udev_exit;
86 static volatile sig_atomic_t worker_exit;
96 static struct pollfd pfd[] = {
97 [FD_NETLINK] = { .events = POLLIN },
98 [FD_WORKER] = { .events = POLLIN },
99 [FD_SIGNAL] = { .events = POLLIN },
100 [FD_INOTIFY] = { .events = POLLIN },
101 [FD_CONTROL] = { .events = POLLIN },
111 struct udev_list_node node;
113 struct udev_device *dev;
114 enum event_state state;
116 unsigned long long int delaying_seqnum;
117 unsigned long long int seqnum;
120 const char *devpath_old;
125 static struct event *node_to_event(struct udev_list_node *node)
129 event = (char *)node;
130 event -= offsetof(struct event, node);
131 return (struct event *)event;
142 struct udev_list_node node;
146 struct udev_monitor *monitor;
147 enum worker_state state;
151 /* passed from worker to main process */
152 struct worker_message {
157 static struct worker *node_to_worker(struct udev_list_node *node)
161 worker = (char *)node;
162 worker -= offsetof(struct worker, node);
163 return (struct worker *)worker;
166 static void event_queue_delete(struct event *event)
168 udev_list_node_remove(&event->node);
170 /* mark as failed, if "add" event returns non-zero */
171 if (event->exitcode != 0 && strcmp(udev_device_get_action(event->dev), "add") == 0)
172 udev_queue_export_device_failed(udev_queue_export, event->dev);
174 udev_queue_export_device_finished(udev_queue_export, event->dev);
176 info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode);
177 udev_device_unref(event->dev);
181 static void event_sig_handler(int signum)
193 static struct worker *worker_ref(struct worker *worker)
199 static void worker_unref(struct worker *worker)
202 if (worker->refcount > 0)
205 udev_list_node_remove(&worker->node);
206 udev_monitor_unref(worker->monitor);
208 info(worker->udev, "worker [%u] cleaned up\n", worker->pid);
212 static void worker_new(struct event *event)
214 struct worker *worker;
215 struct udev_monitor *worker_monitor;
217 struct sigaction act;
219 /* listen for new events */
220 worker_monitor = udev_monitor_new_from_netlink(event->udev, NULL);
221 if (worker_monitor == NULL)
223 /* allow the main daemon netlink address to send devices to the worker */
224 udev_monitor_allow_unicast_sender(worker_monitor, monitor);
225 udev_monitor_enable_receiving(worker_monitor);
226 util_set_fd_cloexec(udev_monitor_get_fd(worker_monitor));
228 worker = calloc(1, sizeof(struct worker));
231 /* worker + event reference */
232 worker->refcount = 2;
233 worker->udev = event->udev;
239 struct udev_device *dev;
240 struct pollfd pmon = {
241 .fd = udev_monitor_get_fd(worker_monitor),
245 udev_queue_export_unref(udev_queue_export);
246 udev_monitor_unref(monitor);
247 udev_ctrl_unref(udev_ctrl);
248 close(pfd[FD_SIGNAL].fd);
249 close(worker_watch[READ_END]);
251 udev_log_init("udevd-work");
252 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
254 /* set signal handlers */
255 memset(&act, 0x00, sizeof(act));
256 act.sa_handler = event_sig_handler;
257 sigemptyset (&act.sa_mask);
259 sigaction(SIGTERM, &act, NULL);
260 sigaction(SIGALRM, &act, NULL);
262 /* unblock SIGALRM */
263 sigfillset(&sigmask);
264 sigdelset(&sigmask, SIGALRM);
265 sigprocmask(SIG_SETMASK, &sigmask, NULL);
266 /* SIGTERM is unblocked in ppoll() */
267 sigdelset(&sigmask, SIGTERM);
269 /* request TERM signal if parent exits */
270 prctl(PR_SET_PDEATHSIG, SIGTERM);
276 struct udev_event *udev_event;
277 struct worker_message msg = {};
281 info(event->udev, "seq %llu running\n", udev_device_get_seqnum(dev));
282 udev_event = udev_event_new(dev);
283 if (udev_event == NULL)
286 /* set timeout to prevent hanging processes */
287 alarm(UDEV_EVENT_TIMEOUT);
289 /* apply rules, create node, symlinks */
290 err = udev_event_execute_rules(udev_event, rules);
292 /* rules may change/disable the timeout */
293 if (udev_device_get_event_timeout(dev) >= 0)
294 alarm(udev_device_get_event_timeout(dev));
297 if (err == 0 && !udev_event->ignore_device && udev_get_run(udev_event->udev))
298 failed = udev_event_execute_run(udev_event,
304 /* apply/restore inotify watch */
305 if (err == 0 && udev_event->inotify_watch) {
306 udev_watch_begin(udev_event->udev, dev);
307 udev_device_update_db(dev);
310 /* send processed event back to libudev listeners */
311 udev_monitor_send_device(worker_monitor, NULL, dev);
313 /* send back the result of the event execution */
316 else if (failed != 0)
317 msg.exitcode = failed;
319 send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0);
321 info(event->udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err);
322 udev_event_unref(udev_event);
323 udev_device_unref(dev);
326 /* wait for more device messages or signal from udevd */
327 while (!worker_exit) {
330 fdcount = ppoll(&pmon, 1, NULL, &sigmask);
334 if (pmon.revents & POLLIN) {
335 dev = udev_monitor_receive_device(worker_monitor);
340 } while (dev != NULL);
342 udev_monitor_unref(worker_monitor);
347 udev_monitor_unref(worker_monitor);
348 event->state = EVENT_QUEUED;
350 err(event->udev, "fork of child failed: %m\n");
353 /* close monitor, but keep address around */
354 udev_monitor_disconnect(worker_monitor);
355 worker->monitor = worker_monitor;
357 worker->state = WORKER_RUNNING;
358 worker->event = event;
359 event->state = EVENT_RUNNING;
360 udev_list_node_append(&worker->node, &worker_list);
362 info(event->udev, "seq %llu forked new worker [%u]\n", udev_device_get_seqnum(event->dev), pid);
367 static void event_run(struct event *event)
369 struct udev_list_node *loop;
371 udev_list_node_foreach(loop, &worker_list) {
372 struct worker *worker = node_to_worker(loop);
375 if (worker->state != WORKER_IDLE)
378 count = udev_monitor_send_device(monitor, worker->monitor, event->dev);
380 err(event->udev, "worker [%u] did not accept message %zi (%m), kill it\n", worker->pid, count);
381 kill(worker->pid, SIGKILL);
382 worker->state = WORKER_KILLED;
386 worker->event = event;
387 worker->state = WORKER_RUNNING;
388 event->state = EVENT_RUNNING;
392 if (childs >= max_childs) {
393 info(event->udev, "maximum number (%i) of childs reached\n", childs);
397 /* start new worker and pass initial device */
401 static void event_queue_insert(struct udev_device *dev)
405 event = calloc(1, sizeof(struct event));
409 event->udev = udev_device_get_udev(dev);
411 event->seqnum = udev_device_get_seqnum(dev);
412 event->devpath = udev_device_get_devpath(dev);
413 event->devpath_len = strlen(event->devpath);
414 event->devpath_old = udev_device_get_devpath_old(dev);
415 event->devnum = udev_device_get_devnum(dev);
416 event->is_block = (strcmp("block", udev_device_get_subsystem(dev)) == 0);
418 udev_queue_export_device_queued(udev_queue_export, dev);
419 info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev),
420 udev_device_get_action(dev), udev_device_get_subsystem(dev));
422 event->state = EVENT_QUEUED;
423 udev_list_node_append(&event->node, &event_list);
425 /* run all events with a timeout set immediately */
426 if (udev_device_get_timeout(dev) > 0) {
432 static void worker_kill(struct udev *udev, int retain)
434 struct udev_list_node *loop;
437 if (childs <= retain)
440 max = childs - retain;
442 udev_list_node_foreach(loop, &worker_list) {
443 struct worker *worker = node_to_worker(loop);
448 if (worker->state == WORKER_KILLED)
451 worker->state = WORKER_KILLED;
452 kill(worker->pid, SIGTERM);
456 static int mem_size_mb(void)
460 long int memsize = -1;
462 f = fopen("/proc/meminfo", "r");
466 while (fgets(buf, sizeof(buf), f) != NULL) {
469 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
470 memsize = value / 1024;
479 /* lookup event for identical, parent, child device */
480 static bool is_devpath_busy(struct event *event)
482 struct udev_list_node *loop;
485 /* check if queue contains events we depend on */
486 udev_list_node_foreach(loop, &event_list) {
487 struct event *loop_event = node_to_event(loop);
489 /* we already found a later event, earlier can not block us, no need to check again */
490 if (loop_event->seqnum < event->delaying_seqnum)
493 /* event we checked earlier still exists, no need to check again */
494 if (loop_event->seqnum == event->delaying_seqnum)
497 /* found ourself, no later event can block us */
498 if (loop_event->seqnum >= event->seqnum)
501 /* check major/minor */
502 if (major(event->devnum) != 0 && event->devnum == loop_event->devnum && event->is_block == loop_event->is_block)
505 /* check our old name */
506 if (event->devpath_old != NULL && strcmp(loop_event->devpath, event->devpath_old) == 0) {
507 event->delaying_seqnum = loop_event->seqnum;
511 /* compare devpath */
512 common = MIN(loop_event->devpath_len, event->devpath_len);
514 /* one devpath is contained in the other? */
515 if (memcmp(loop_event->devpath, event->devpath, common) != 0)
518 /* identical device event found */
519 if (loop_event->devpath_len == event->devpath_len) {
520 event->delaying_seqnum = loop_event->seqnum;
524 /* parent device event found */
525 if (event->devpath[common] == '/') {
526 event->delaying_seqnum = loop_event->seqnum;
530 /* child device event found */
531 if (loop_event->devpath[common] == '/') {
532 event->delaying_seqnum = loop_event->seqnum;
536 /* no matching device */
543 static void events_start(struct udev *udev)
545 struct udev_list_node *loop;
547 udev_list_node_foreach(loop, &event_list) {
548 struct event *event = node_to_event(loop);
550 if (event->state != EVENT_QUEUED)
553 /* do not start event if parent or child event is still running */
554 if (is_devpath_busy(event)) {
555 dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath);
563 static void worker_returned(void)
566 struct worker_message msg;
568 struct udev_list_node *loop;
570 size = recv(pfd[FD_WORKER].fd, &msg, sizeof(struct worker_message), MSG_DONTWAIT);
571 if (size != sizeof(struct worker_message))
574 /* lookup worker who sent the signal */
575 udev_list_node_foreach(loop, &worker_list) {
576 struct worker *worker = node_to_worker(loop);
578 if (worker->pid != msg.pid)
581 /* worker returned */
582 worker->event->exitcode = msg.exitcode;
583 event_queue_delete(worker->event);
584 worker->event = NULL;
585 if (worker->state != WORKER_KILLED)
586 worker->state = WORKER_IDLE;
587 worker_unref(worker);
593 /* receive the udevd message from userspace */
594 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
596 struct udev *udev = udev_ctrl_get_udev(uctrl);
597 struct udev_ctrl_msg *ctrl_msg;
601 ctrl_msg = udev_ctrl_receive_msg(uctrl);
602 if (ctrl_msg == NULL)
605 i = udev_ctrl_get_set_log_level(ctrl_msg);
607 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
608 udev_set_log_priority(udev, i);
609 worker_kill(udev, 0);
612 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
613 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
614 stop_exec_queue = true;
617 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
618 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
619 stop_exec_queue = false;
622 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
623 info(udev, "udevd message (RELOAD_RULES) received\n");
624 reload_config = true;
627 str = udev_ctrl_get_set_env(ctrl_msg);
635 val = strchr(key, '=');
639 if (val[0] == '\0') {
640 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
641 udev_add_property(udev, key, NULL);
643 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
644 udev_add_property(udev, key, val);
647 err(udev, "wrong key format '%s'\n", key);
651 worker_kill(udev, 0);
654 i = udev_ctrl_get_set_max_childs(ctrl_msg);
656 info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
660 settle_pid = udev_ctrl_get_settle(ctrl_msg);
661 if (settle_pid > 0) {
662 info(udev, "udevd message (SETTLE) received\n");
663 kill(settle_pid, SIGUSR1);
666 udev_ctrl_msg_unref(ctrl_msg);
669 /* read inotify messages */
670 static int handle_inotify(struct udev *udev)
674 struct inotify_event *ev;
676 if ((ioctl(pfd[FD_INOTIFY].fd, FIONREAD, &nbytes) < 0) || (nbytes <= 0))
679 buf = malloc(nbytes);
681 err(udev, "error getting buffer for inotify\n");
685 nbytes = read(pfd[FD_INOTIFY].fd, buf, nbytes);
687 for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) {
688 struct udev_device *dev;
690 ev = (struct inotify_event *)(buf + pos);
692 dbg(udev, "inotify event: %x for %s\n", ev->mask, ev->name);
693 reload_config = true;
697 dev = udev_watch_lookup(udev, ev->wd);
699 dbg(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev));
700 if (ev->mask & IN_CLOSE_WRITE) {
701 char filename[UTIL_PATH_SIZE];
704 info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev));
705 util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
706 fd = open(filename, O_WRONLY);
707 if (fd < 0 || write(fd, "change", 6) < 0)
708 info(udev, "error writing uevent: %m\n");
711 if (ev->mask & IN_IGNORED)
712 udev_watch_end(udev, dev);
714 udev_device_unref(dev);
723 static void handle_signal(struct udev *udev, int signo)
734 struct udev_list_node *loop, *tmp;
736 pid = waitpid(-1, &status, WNOHANG);
740 udev_list_node_foreach_safe(loop, tmp, &worker_list) {
741 struct worker *worker = node_to_worker(loop);
743 if (worker->pid != pid)
746 info(udev, "worker [%u] exit\n", pid);
747 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
748 err(udev, "worker [%u] unexpectedly returned with status 0x%04x\n", pid, status);
749 if (worker->event != NULL) {
750 err(udev, "worker [%u] failed while handling '%s'\n", pid, worker->event->devpath);
751 worker->event->exitcode = -32;
752 event_queue_delete(worker->event);
753 /* drop reference from running event */
754 worker_unref(worker);
757 worker_unref(worker);
763 reload_config = true;
768 static void startup_log(struct udev *udev)
771 char path[UTIL_PATH_SIZE];
774 f = fopen("/dev/kmsg", "w");
776 fprintf(f, "<6>udev: starting version " VERSION "\n");
778 util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/class/mem/null", NULL);
779 if (lstat(path, &statbuf) == 0 && S_ISDIR(statbuf.st_mode)) {
780 const char *depr_str =
781 "udev: missing sysfs features; please update the kernel "
782 "or disable the kernel's CONFIG_SYSFS_DEPRECATED option; "
783 "udev may fail to work correctly";
786 fprintf(f, "<3>%s\n", depr_str);
787 err(udev, "%s\n", depr_str);
795 int main(int argc, char *argv[])
801 int daemonize = false;
802 int resolve_names = 1;
803 static const struct option options[] = {
804 { "daemon", no_argument, NULL, 'd' },
805 { "debug-trace", no_argument, NULL, 't' },
806 { "debug", no_argument, NULL, 'D' },
807 { "help", no_argument, NULL, 'h' },
808 { "version", no_argument, NULL, 'V' },
809 { "resolve-names", required_argument, NULL, 'N' },
818 udev_log_init("udevd");
819 udev_set_log_fn(udev, log_fn);
820 info(udev, "version %s\n", VERSION);
821 udev_selinux_init(udev);
826 option = getopt_long(argc, argv, "dDthV", options, NULL);
839 if (udev_get_log_priority(udev) < LOG_INFO)
840 udev_set_log_priority(udev, LOG_INFO);
843 if (strcmp (optarg, "early") == 0) {
845 } else if (strcmp (optarg, "late") == 0) {
847 } else if (strcmp (optarg, "never") == 0) {
850 fprintf(stderr, "resolve-names must be early, late or never\n");
851 err(udev, "resolve-names must be early, late or never\n");
856 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] "
857 "[--resolve-names=early|late|never] [--version]\n");
860 printf("%s\n", VERSION);
868 fprintf(stderr, "root privileges required\n");
869 err(udev, "root privileges required\n");
873 /* make sure std{in,out,err} fd's are in a sane state */
874 fd = open("/dev/null", O_RDWR);
876 fprintf(stderr, "cannot open /dev/null\n");
877 err(udev, "cannot open /dev/null\n");
879 if (write(STDOUT_FILENO, 0, 0) < 0)
880 dup2(fd, STDOUT_FILENO);
881 if (write(STDERR_FILENO, 0, 0) < 0)
882 dup2(fd, STDERR_FILENO);
884 /* init control socket, bind() ensures, that only one udevd instance is running */
885 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
886 if (udev_ctrl == NULL) {
887 fprintf(stderr, "error initializing control socket");
888 err(udev, "error initializing udevd socket");
892 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
893 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
894 err(udev, "error binding control socket, seems udevd is already running\n");
898 pfd[FD_CONTROL].fd = udev_ctrl_get_fd(udev_ctrl);
900 monitor = udev_monitor_new_from_netlink(udev, "kernel");
901 if (monitor == NULL || udev_monitor_enable_receiving(monitor) < 0) {
902 fprintf(stderr, "error initializing netlink socket\n");
903 err(udev, "error initializing netlink socket\n");
907 udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
908 pfd[FD_NETLINK].fd = udev_monitor_get_fd(monitor);
910 pfd[FD_INOTIFY].fd = udev_watch_init(udev);
911 if (pfd[FD_INOTIFY].fd < 0) {
912 fprintf(stderr, "error initializing inotify\n");
913 err(udev, "error initializing inotify\n");
918 if (udev_get_rules_path(udev) != NULL) {
919 inotify_add_watch(pfd[FD_INOTIFY].fd, udev_get_rules_path(udev),
920 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
922 char filename[UTIL_PATH_SIZE];
924 inotify_add_watch(pfd[FD_INOTIFY].fd, LIBEXECDIR "/rules.d",
925 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
926 inotify_add_watch(pfd[FD_INOTIFY].fd, SYSCONFDIR "/udev/rules.d",
927 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
929 /* watch dynamic rules directory */
930 util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/rules.d", NULL);
931 inotify_add_watch(pfd[FD_INOTIFY].fd, filename,
932 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
934 udev_watch_restore(udev);
936 /* block and listen to all signals on signalfd */
938 sigprocmask(SIG_SETMASK, &mask, &orig_sigmask);
939 pfd[FD_SIGNAL].fd = signalfd(-1, &mask, 0);
940 if (pfd[FD_SIGNAL].fd < 0) {
941 fprintf(stderr, "error getting signalfd\n");
942 err(udev, "error getting signalfd\n");
947 /* unnamed socket from workers to the main daemon */
948 if (socketpair(AF_LOCAL, SOCK_DGRAM, 0, worker_watch) < 0) {
949 fprintf(stderr, "error getting socketpair\n");
950 err(udev, "error getting socketpair\n");
954 pfd[FD_WORKER].fd = worker_watch[READ_END];
955 util_set_fd_cloexec(worker_watch[WRITE_END]);
957 rules = udev_rules_new(udev, resolve_names);
959 err(udev, "error reading rules\n");
963 udev_queue_export = udev_queue_export_new(udev);
964 if (udev_queue_export == NULL) {
965 err(udev, "error creating queue file\n");
977 err(udev, "fork of daemon failed: %m\n");
988 /* redirect std{out,err} */
989 if (!debug && !debug_trace) {
990 dup2(fd, STDIN_FILENO);
991 dup2(fd, STDOUT_FILENO);
992 dup2(fd, STDERR_FILENO);
994 if (fd > STDERR_FILENO)
997 /* set scheduling priority for the daemon */
998 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
1004 /* OOM_DISABLE == -17 */
1005 fd = open("/proc/self/oom_adj", O_RDWR);
1007 err(udev, "error disabling OOM: %m\n");
1009 write(fd, "-17", 3);
1013 /* in trace mode run one event after the other */
1017 int memsize = mem_size_mb();
1020 max_childs = 128 + (memsize / 8);
1025 /* possibly overwrite maximum limit of executed events */
1026 value = getenv("UDEVD_MAX_CHILDS");
1028 max_childs = strtoul(value, NULL, 10);
1029 info(udev, "initialize max_childs to %u\n", max_childs);
1031 udev_list_init(&event_list);
1032 udev_list_init(&worker_list);
1034 while (!udev_exit) {
1038 /* set timeout to kill idle workers */
1039 if (udev_list_is_empty(&event_list) && childs > 2)
1043 /* wait for events */
1044 fdcount = poll(pfd, ARRAY_SIZE(pfd), timeout);
1048 /* timeout - kill idle workers */
1050 worker_kill(udev, 2);
1052 /* event has finished */
1053 if (pfd[FD_WORKER].revents & POLLIN)
1056 /* get kernel uevent */
1057 if (pfd[FD_NETLINK].revents & POLLIN) {
1058 struct udev_device *dev;
1060 dev = udev_monitor_receive_device(monitor);
1062 event_queue_insert(dev);
1064 udev_device_unref(dev);
1067 /* start new events */
1068 if (!udev_list_is_empty(&event_list) && !stop_exec_queue)
1072 if (pfd[FD_SIGNAL].revents & POLLIN) {
1073 struct signalfd_siginfo fdsi;
1076 size = read(pfd[FD_SIGNAL].fd, &fdsi, sizeof(struct signalfd_siginfo));
1077 if (size == sizeof(struct signalfd_siginfo))
1078 handle_signal(udev, fdsi.ssi_signo);
1081 /* device node and rules directory inotify watch */
1082 if (pfd[FD_INOTIFY].revents & POLLIN)
1083 handle_inotify(udev);
1086 * get control message
1088 * This needs to be after the inotify handling, to make sure,
1089 * that the settle signal is send back after the possibly generated
1090 * "change" events by the inotify device node watch.
1092 if (pfd[FD_CONTROL].revents & POLLIN)
1093 handle_ctrl_msg(udev_ctrl);
1095 /* rules changed, set by inotify or a HUP signal */
1096 if (reload_config) {
1097 struct udev_rules *rules_new;
1099 worker_kill(udev, 0);
1100 rules_new = udev_rules_new(udev, resolve_names);
1101 if (rules_new != NULL) {
1102 udev_rules_unref(rules);
1109 udev_queue_export_cleanup(udev_queue_export);
1112 udev_queue_export_unref(udev_queue_export);
1113 udev_rules_unref(rules);
1114 udev_ctrl_unref(udev_ctrl);
1115 if (pfd[FD_SIGNAL].fd >= 0)
1116 close(pfd[FD_SIGNAL].fd);
1117 if (worker_watch[READ_END] >= 0)
1118 close(worker_watch[READ_END]);
1119 if (worker_watch[WRITE_END] >= 0)
1120 close(worker_watch[WRITE_END]);
1121 udev_monitor_unref(monitor);
1122 udev_selinux_exit(udev);