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>
38 #include <sys/ioctl.h>
39 #include <linux/types.h>
40 #include <linux/netlink.h>
42 #include <sys/inotify.h>
46 #include "udev_rules.h"
48 #define UDEVD_PRIORITY -4
49 #define UDEV_PRIORITY -2
51 /* maximum limit of forked childs */
52 #define UDEVD_MAX_CHILDS 256
56 static void log_fn(struct udev *udev, int priority,
57 const char *file, int line, const char *fn,
58 const char *format, va_list args)
61 fprintf(stderr, "[%d] %s: ", (int) getpid(), fn);
62 vfprintf(stderr, format, args);
64 vsyslog(priority, format, args);
68 struct udevd_uevent_msg {
70 struct list_head node;
79 unsigned long long seqnum;
83 char *envp[UEVENT_NUM_ENVP+1];
87 static int debug_trace;
88 static struct udev_rules rules;
89 static struct udev_ctrl *udev_ctrl;
90 static int uevent_netlink_sock = -1;
91 static int inotify_fd = -1;
93 static int signal_pipe[2] = {-1, -1};
94 static volatile int sigchilds_waiting;
95 static volatile int udev_exit;
96 static volatile int reload_config;
97 static int run_exec_q;
98 static int stop_exec_q;
99 static int max_childs;
100 static char udev_log_env[32];
102 static LIST_HEAD(exec_list);
103 static LIST_HEAD(running_list);
105 static void asmlinkage udev_event_sig_handler(int signum)
107 if (signum == SIGALRM)
111 static int udev_event_process(struct udevd_uevent_msg *msg)
113 struct sigaction act;
114 struct udevice *udevice;
118 /* set signal handlers */
119 memset(&act, 0x00, sizeof(act));
120 act.sa_handler = (void (*)(int)) udev_event_sig_handler;
121 sigemptyset (&act.sa_mask);
123 sigaction(SIGALRM, &act, NULL);
125 /* reset to default */
126 act.sa_handler = SIG_DFL;
127 sigaction(SIGINT, &act, NULL);
128 sigaction(SIGTERM, &act, NULL);
129 sigaction(SIGCHLD, &act, NULL);
130 sigaction(SIGHUP, &act, NULL);
132 /* trigger timeout to prevent hanging processes */
133 alarm(UDEV_EVENT_TIMEOUT);
135 /* reconstruct event environment from message */
136 for (i = 0; msg->envp[i]; i++)
137 putenv(msg->envp[i]);
139 udevice = udev_device_init(msg->udev);
142 util_strlcpy(udevice->action, msg->action, sizeof(udevice->action));
143 sysfs_device_set_values(udevice->udev, udevice->dev, msg->devpath, msg->subsystem, msg->driver);
144 udevice->devpath_old = msg->devpath_old;
145 udevice->devt = msg->devt;
147 retval = udev_device_event(&rules, udevice);
149 /* rules may change/disable the timeout */
150 if (udevice->event_timeout >= 0)
151 alarm(udevice->event_timeout);
153 /* run programs collected by RUN-key*/
154 if (retval == 0 && !udevice->ignore_device && udev_get_run(msg->udev))
155 retval = udev_rules_run(udevice);
157 udev_device_cleanup(udevice);
167 static void export_event_state(struct udevd_uevent_msg *msg, enum event_state state)
169 char filename[UTIL_PATH_SIZE];
170 char filename_failed[UTIL_PATH_SIZE];
173 /* location of queue file */
174 snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu", udev_get_dev_path(msg->udev), msg->seqnum);
176 /* location of failed file */
177 util_strlcpy(filename_failed, udev_get_dev_path(msg->udev), sizeof(filename_failed));
178 util_strlcat(filename_failed, "/", sizeof(filename_failed));
179 start = util_strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed));
180 util_strlcat(filename_failed, msg->devpath, sizeof(filename_failed));
181 util_path_encode(&filename_failed[start], sizeof(filename_failed) - start);
185 unlink(filename_failed);
186 delete_path(msg->udev, filename_failed);
187 create_path(msg->udev, filename);
188 udev_selinux_setfscreatecon(msg->udev, filename, S_IFLNK);
189 symlink(msg->devpath, filename);
190 udev_selinux_resetfscreatecon(msg->udev);
193 if (msg->devpath_old != NULL) {
194 /* "move" event - rename failed file to current name, do not delete failed */
195 char filename_failed_old[UTIL_PATH_SIZE];
197 util_strlcpy(filename_failed_old, udev_get_dev_path(msg->udev), sizeof(filename_failed_old));
198 util_strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
199 start = util_strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old));
200 util_strlcat(filename_failed_old, msg->devpath_old, sizeof(filename_failed_old));
201 util_path_encode(&filename_failed_old[start], sizeof(filename) - start);
203 if (rename(filename_failed_old, filename_failed) == 0)
204 info(msg->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
205 msg->devpath_old, msg->devpath);
207 unlink(filename_failed);
208 delete_path(msg->udev, filename_failed);
212 delete_path(msg->udev, filename);
215 /* move failed event to the failed directory */
216 create_path(msg->udev, filename_failed);
217 rename(filename, filename_failed);
219 /* clean up possibly empty queue directory */
220 delete_path(msg->udev, filename);
227 static void msg_queue_delete(struct udevd_uevent_msg *msg)
229 list_del(&msg->node);
231 /* mark as failed, if "add" event returns non-zero */
232 if (msg->exitstatus && strcmp(msg->action, "add") == 0)
233 export_event_state(msg, EVENT_FAILED);
235 export_event_state(msg, EVENT_FINISHED);
240 static void udev_event_run(struct udevd_uevent_msg *msg)
249 close(uevent_netlink_sock);
250 udev_ctrl_unref(udev_ctrl);
253 close(signal_pipe[READ_END]);
254 close(signal_pipe[WRITE_END]);
256 logging_init("udevd-event");
257 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
259 retval = udev_event_process(msg);
260 info(msg->udev, "seq %llu finished with %i\n", msg->seqnum, retval);
267 err(msg->udev, "fork of child failed: %m\n");
268 msg_queue_delete(msg);
271 /* get SIGCHLD in main loop */
272 info(msg->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
273 msg->seqnum, pid, msg->action, msg->subsystem, time(NULL) - msg->queue_time);
278 static void msg_queue_insert(struct udevd_uevent_msg *msg)
280 char filename[UTIL_PATH_SIZE];
283 msg->queue_time = time(NULL);
285 export_event_state(msg, EVENT_QUEUED);
286 info(msg->udev, "seq %llu queued, '%s' '%s'\n", msg->seqnum, msg->action, msg->subsystem);
288 util_strlcpy(filename, udev_get_dev_path(msg->udev), sizeof(filename));
289 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
290 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
295 len = sprintf(str, "%llu\n", msg->seqnum);
300 /* run one event after the other in debug mode */
302 list_add_tail(&msg->node, &running_list);
304 waitpid(msg->pid, NULL, 0);
305 msg_queue_delete(msg);
309 /* run all events with a timeout set immediately */
310 if (msg->timeout != 0) {
311 list_add_tail(&msg->node, &running_list);
316 list_add_tail(&msg->node, &exec_list);
320 static int mem_size_mb(void)
324 long int memsize = -1;
326 f = fopen("/proc/meminfo", "r");
330 while (fgets(buf, sizeof(buf), f) != NULL) {
333 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
334 memsize = value / 1024;
343 static int compare_devpath(const char *running, const char *waiting)
347 for (i = 0; i < UTIL_PATH_SIZE; i++) {
348 /* identical device event found */
349 if (running[i] == '\0' && waiting[i] == '\0')
352 /* parent device event found */
353 if (running[i] == '\0' && waiting[i] == '/')
356 /* child device event found */
357 if (running[i] == '/' && waiting[i] == '\0')
360 /* no matching event */
361 if (running[i] != waiting[i])
368 /* lookup event for identical, parent, child, or physical device */
369 static int devpath_busy(struct udevd_uevent_msg *msg, int limit)
371 struct udevd_uevent_msg *loop_msg;
372 int childs_count = 0;
374 /* check exec-queue which may still contain delayed events we depend on */
375 list_for_each_entry(loop_msg, &exec_list, node) {
376 /* skip ourself and all later events */
377 if (loop_msg->seqnum >= msg->seqnum)
380 /* check our old name */
381 if (msg->devpath_old != NULL)
382 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
385 /* check identical, parent, or child device event */
386 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
387 dbg(msg->udev, "%llu, device event still pending %llu (%s)\n",
388 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
392 /* check for our major:minor number */
393 if (msg->devt && loop_msg->devt == msg->devt &&
394 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
395 dbg(msg->udev, "%llu, device event still pending %llu (%d:%d)\n", msg->seqnum,
396 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
400 /* check physical device event (special case of parent) */
401 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
402 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
403 dbg(msg->udev, "%llu, physical device event still pending %llu (%s)\n",
404 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
409 /* check run queue for still running events */
410 list_for_each_entry(loop_msg, &running_list, node) {
413 if (childs_count++ >= limit) {
414 info(msg->udev, "%llu, maximum number (%i) of childs reached\n", msg->seqnum, childs_count);
418 /* check our old name */
419 if (msg->devpath_old != NULL)
420 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
423 /* check identical, parent, or child device event */
424 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
425 dbg(msg->udev, "%llu, device event still running %llu (%s)\n",
426 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
430 /* check for our major:minor number */
431 if (msg->devt && loop_msg->devt == msg->devt &&
432 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
433 dbg(msg->udev, "%llu, device event still running %llu (%d:%d)\n", msg->seqnum,
434 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
438 /* check physical device event (special case of parent) */
439 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
440 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
441 dbg(msg->udev, "%llu, physical device event still running %llu (%s)\n",
442 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
449 /* serializes events for the identical and parent and child devices */
450 static void msg_queue_manager(struct udev *udev)
452 struct udevd_uevent_msg *loop_msg;
453 struct udevd_uevent_msg *tmp_msg;
455 if (list_empty(&exec_list))
458 list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, node) {
459 /* serialize and wait for parent or child events */
460 if (devpath_busy(loop_msg, max_childs) != 0) {
461 dbg(udev, "delay seq %llu (%s)\n", loop_msg->seqnum, loop_msg->devpath);
465 /* move event to run list */
466 list_move_tail(&loop_msg->node, &running_list);
467 udev_event_run(loop_msg);
468 dbg(udev, "moved seq %llu to running list\n", loop_msg->seqnum);
472 static struct udevd_uevent_msg *get_msg_from_envbuf(struct udev *udev, const char *buf, int buf_size)
476 struct udevd_uevent_msg *msg;
477 char *physdevdriver_key = NULL;
481 msg = malloc(sizeof(struct udevd_uevent_msg) + buf_size);
484 memset(msg, 0x00, sizeof(struct udevd_uevent_msg) + buf_size);
487 /* copy environment buffer and reconstruct envp */
488 memcpy(msg->envbuf, buf, buf_size);
490 for (i = 0; (bufpos < buf_size) && (i < UEVENT_NUM_ENVP-2); i++) {
494 key = &msg->envbuf[bufpos];
495 keylen = strlen(key);
497 bufpos += keylen + 1;
498 dbg(udev, "add '%s' to msg.envp[%i]\n", msg->envp[i], i);
500 /* remember some keys for further processing */
501 if (strncmp(key, "ACTION=", 7) == 0)
502 msg->action = &key[7];
503 else if (strncmp(key, "DEVPATH=", 8) == 0)
504 msg->devpath = &key[8];
505 else if (strncmp(key, "SUBSYSTEM=", 10) == 0)
506 msg->subsystem = &key[10];
507 else if (strncmp(key, "DRIVER=", 7) == 0)
508 msg->driver = &key[7];
509 else if (strncmp(key, "SEQNUM=", 7) == 0)
510 msg->seqnum = strtoull(&key[7], NULL, 10);
511 else if (strncmp(key, "DEVPATH_OLD=", 12) == 0)
512 msg->devpath_old = &key[12];
513 else if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
514 msg->physdevpath = &key[12];
515 else if (strncmp(key, "PHYSDEVDRIVER=", 14) == 0)
516 physdevdriver_key = key;
517 else if (strncmp(key, "MAJOR=", 6) == 0)
518 maj = strtoull(&key[6], NULL, 10);
519 else if (strncmp(key, "MINOR=", 6) == 0)
520 min = strtoull(&key[6], NULL, 10);
521 else if (strncmp(key, "TIMEOUT=", 8) == 0)
522 msg->timeout = strtoull(&key[8], NULL, 10);
524 msg->devt = makedev(maj, min);
525 msg->envp[i++] = "UDEVD_EVENT=1";
527 if (msg->driver == NULL && msg->physdevpath == NULL && physdevdriver_key != NULL) {
528 /* for older kernels DRIVER is empty for a bus device, export PHYSDEVDRIVER as DRIVER */
529 msg->envp[i++] = &physdevdriver_key[7];
530 msg->driver = &physdevdriver_key[14];
535 if (msg->devpath == NULL || msg->action == NULL) {
536 info(udev, "DEVPATH or ACTION missing, ignore message\n");
543 /* receive the udevd message from userspace */
544 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
546 struct udev *udev = udev_ctrl_get_udev(uctrl);
547 struct udev_ctrl_msg *ctrl_msg;
551 ctrl_msg = udev_ctrl_receive_msg(uctrl);
552 if (ctrl_msg == NULL)
555 i = udev_ctrl_get_set_log_level(ctrl_msg);
557 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
558 udev_set_log_priority(udev, i);
559 sprintf(udev_log_env, "UDEV_LOG=%i", i);
560 putenv(udev_log_env);
563 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
564 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
568 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
569 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
571 msg_queue_manager(udev);
574 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
575 info(udev, "udevd message (RELOAD_RULES) received\n");
579 str = udev_ctrl_get_set_env(ctrl_msg);
581 char *key = strdup(str);
584 val = strchr(str, '=');
588 if (val[0] == '\0') {
589 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
592 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
596 err(udev, "wrong key format '%s'\n", key);
601 i = udev_ctrl_get_set_max_childs(ctrl_msg);
603 info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
607 udev_ctrl_msg_unref(ctrl_msg);
610 /* receive the kernel user event message and do some sanity checks */
611 static struct udevd_uevent_msg *get_netlink_msg(struct udev *udev)
613 struct udevd_uevent_msg *msg;
616 static char buffer[UEVENT_BUFFER_SIZE+512];
619 size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
622 err(udev, "unable to receive kernel netlink message: %m\n");
626 if ((size_t)size > sizeof(buffer)-1)
627 size = sizeof(buffer)-1;
629 dbg(udev, "uevent_size=%zi\n", size);
631 /* start of event payload */
632 bufpos = strlen(buffer)+1;
633 msg = get_msg_from_envbuf(udev, &buffer[bufpos], size-bufpos);
637 /* validate message */
638 pos = strchr(buffer, '@');
640 err(udev, "invalid uevent '%s'\n", buffer);
646 if (msg->action == NULL) {
647 info(udev, "no ACTION in payload found, skip event '%s'\n", buffer);
652 if (strcmp(msg->action, buffer) != 0) {
653 err(udev, "ACTION in payload does not match uevent, skip event '%s'\n", buffer);
661 static void asmlinkage sig_handler(int signum)
669 /* set flag, then write to pipe if needed */
670 sigchilds_waiting = 1;
677 /* write to pipe, which will wakeup select() in our mainloop */
678 write(signal_pipe[WRITE_END], "", 1);
681 static void udev_done(int pid, int exitstatus)
683 /* find msg associated with pid and delete it */
684 struct udevd_uevent_msg *msg;
686 list_for_each_entry(msg, &running_list, node) {
687 if (msg->pid == pid) {
688 info(msg->udev, "seq %llu, pid [%d] exit with %i, %ld seconds old\n", msg->seqnum, msg->pid,
689 exitstatus, time(NULL) - msg->queue_time);
690 msg->exitstatus = exitstatus;
691 msg_queue_delete(msg);
693 /* there may be events waiting with the same devpath */
700 static void reap_sigchilds(void)
706 pid = waitpid(-1, &status, WNOHANG);
709 if (WIFEXITED(status))
710 status = WEXITSTATUS(status);
711 else if (WIFSIGNALED(status))
712 status = WTERMSIG(status) + 128;
715 udev_done(pid, status);
719 static int init_uevent_netlink_sock(struct udev *udev)
721 struct sockaddr_nl snl;
722 const int buffersize = 16 * 1024 * 1024;
725 memset(&snl, 0x00, sizeof(struct sockaddr_nl));
726 snl.nl_family = AF_NETLINK;
727 snl.nl_pid = getpid();
730 uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
731 if (uevent_netlink_sock == -1) {
732 err(udev, "error getting socket: %m\n");
736 /* set receive buffersize */
737 setsockopt(uevent_netlink_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
739 retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
741 err(udev, "bind failed: %m\n");
742 close(uevent_netlink_sock);
743 uevent_netlink_sock = -1;
749 static void export_initial_seqnum(struct udev *udev)
751 char filename[UTIL_PATH_SIZE];
756 util_strlcpy(filename, udev_get_sys_path(udev), sizeof(filename));
757 util_strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
758 fd = open(filename, O_RDONLY);
760 len = read(fd, seqnum, sizeof(seqnum)-1);
764 strcpy(seqnum, "0\n");
767 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
768 util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
769 create_path(udev, filename);
770 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
772 write(fd, seqnum, len);
777 int main(int argc, char *argv[])
782 struct sigaction act;
786 static const struct option options[] = {
787 { "daemon", no_argument, NULL, 'd' },
788 { "debug-trace", no_argument, NULL, 't' },
789 { "debug", no_argument, NULL, 'D' },
790 { "help", no_argument, NULL, 'h' },
791 { "version", no_argument, NULL, 'V' },
801 logging_init("udevd");
802 udev_set_log_fn(udev, log_fn);
803 dbg(udev, "version %s\n", VERSION);
809 option = getopt_long(argc, argv, "dDthV", options, NULL);
822 if (udev_get_log_priority(udev) < LOG_INFO)
823 udev_set_log_priority(udev, LOG_INFO);
826 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
829 printf("%s\n", VERSION);
837 fprintf(stderr, "root privileges required\n");
838 err(udev, "root privileges required\n");
842 /* make sure std{in,out,err} fd's are in a sane state */
843 fd = open("/dev/null", O_RDWR);
845 fprintf(stderr, "cannot open /dev/null\n");
846 err(udev, "cannot open /dev/null\n");
848 if (fd > STDIN_FILENO)
849 dup2(fd, STDIN_FILENO);
850 if (write(STDOUT_FILENO, 0, 0) < 0)
851 dup2(fd, STDOUT_FILENO);
852 if (write(STDERR_FILENO, 0, 0) < 0)
853 dup2(fd, STDERR_FILENO);
855 /* init control socket, bind() ensures, that only one udevd instance is running */
856 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
857 if (udev_ctrl == NULL) {
858 fprintf(stderr, "error initializing control socket");
859 err(udev, "error initializing udevd socket");
864 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
865 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
866 err(udev, "error binding control socket, seems udevd is already running\n");
871 if (init_uevent_netlink_sock(udev) < 0) {
872 fprintf(stderr, "error initializing netlink socket\n");
873 err(udev, "error initializing netlink socket\n");
878 retval = pipe(signal_pipe);
880 err(udev, "error getting pipes: %m\n");
884 retval = fcntl(signal_pipe[READ_END], F_GETFL, 0);
886 err(udev, "error fcntl on read pipe: %m\n");
889 retval = fcntl(signal_pipe[READ_END], F_SETFL, retval | O_NONBLOCK);
891 err(udev, "error fcntl on read pipe: %m\n");
895 retval = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
897 err(udev, "error fcntl on write pipe: %m\n");
900 retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
902 err(udev, "error fcntl on write pipe: %m\n");
906 /* parse the rules and keep them in memory */
908 udev_rules_init(udev, &rules, 1);
910 export_initial_seqnum(udev);
918 dbg(udev, "daemonized fork running\n");
921 err(udev, "fork of daemon failed: %m\n");
925 dbg(udev, "child [%u] running, parent exits\n", pid);
931 /* redirect std{out,err} */
933 dup2(fd, STDOUT_FILENO);
934 dup2(fd, STDERR_FILENO);
936 if (fd > STDERR_FILENO)
939 /* set scheduling priority for the daemon */
940 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
946 /* OOM_DISABLE == -17 */
947 fd = open("/proc/self/oom_adj", O_RDWR);
949 err(udev, "error disabling OOM: %m\n");
955 fd = open("/dev/kmsg", O_WRONLY);
957 const char *ver_str = "<6>udev: starting version " VERSION "\n";
958 char path[UTIL_PATH_SIZE];
961 write(fd, ver_str, strlen(ver_str));
962 util_strlcpy(path, udev_get_sys_path(udev), sizeof(path));
963 util_strlcat(path, "/class/mem/null", sizeof(path));
964 if (lstat(path, &statbuf) == 0) {
965 if (S_ISDIR(statbuf.st_mode)) {
966 const char *depr_str = "<6>udev: deprecated sysfs layout "
967 "(CONFIG_SYSFS_DEPRECATED) is unsupported\n";
969 write(fd, depr_str, strlen(depr_str));
975 /* set signal handlers */
976 memset(&act, 0x00, sizeof(struct sigaction));
977 act.sa_handler = (void (*)(int)) sig_handler;
978 sigemptyset(&act.sa_mask);
979 act.sa_flags = SA_RESTART;
980 sigaction(SIGINT, &act, NULL);
981 sigaction(SIGTERM, &act, NULL);
982 sigaction(SIGCHLD, &act, NULL);
983 sigaction(SIGHUP, &act, NULL);
985 /* watch rules directory */
986 inotify_fd = inotify_init();
987 if (inotify_fd >= 0) {
988 if (udev_get_rules_path(udev) != NULL) {
989 inotify_add_watch(inotify_fd, udev_get_rules_path(udev),
990 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
992 char filename[PATH_MAX];
994 inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d",
995 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
996 inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d",
997 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
999 /* watch dynamic rules directory */
1000 util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
1001 util_strlcat(filename, "/.udev/rules.d", sizeof(filename));
1002 inotify_add_watch(inotify_fd, filename,
1003 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1005 } else if (errno == ENOSYS)
1006 err(udev, "the kernel does not support inotify, udevd can't monitor rules file changes\n");
1008 err(udev, "inotify_init failed: %m\n");
1010 /* maximum limit of forked childs */
1011 value = getenv("UDEVD_MAX_CHILDS");
1013 max_childs = strtoul(value, NULL, 10);
1015 int memsize = mem_size_mb();
1017 max_childs = 128 + (memsize / 4);
1019 max_childs = UDEVD_MAX_CHILDS;
1021 info(udev, "initialize max_childs to %u\n", max_childs);
1023 /* clear environment for forked event processes */
1026 /* export log_priority , as called programs may want to follow that setting */
1027 sprintf(udev_log_env, "UDEV_LOG=%i", udev_get_log_priority(udev));
1028 putenv(udev_log_env);
1032 maxfd = udev_ctrl_get_fd(udev_ctrl);
1033 maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
1034 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
1035 maxfd = UDEV_MAX(maxfd, inotify_fd);
1037 while (!udev_exit) {
1038 struct udevd_uevent_msg *msg;
1042 FD_SET(signal_pipe[READ_END], &readfds);
1043 FD_SET(udev_ctrl_get_fd(udev_ctrl), &readfds);
1044 FD_SET(uevent_netlink_sock, &readfds);
1045 if (inotify_fd >= 0)
1046 FD_SET(inotify_fd, &readfds);
1048 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
1051 err(udev, "error in select: %m\n");
1055 /* get control message */
1056 if (FD_ISSET(udev_ctrl_get_fd(udev_ctrl), &readfds))
1057 handle_ctrl_msg(udev_ctrl);
1059 /* get netlink message */
1060 if (FD_ISSET(uevent_netlink_sock, &readfds)) {
1061 msg = get_netlink_msg(udev);
1063 msg_queue_insert(msg);
1066 /* received a signal, clear our notification pipe */
1067 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
1070 read(signal_pipe[READ_END], &buf, sizeof(buf));
1073 /* rules directory inotify watch */
1074 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
1077 /* discard all possible events, we can just reload the config */
1078 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
1082 buf = malloc(nbytes);
1084 err(udev, "error getting buffer for inotify, disable watching\n");
1088 read(inotify_fd, buf, nbytes);
1093 /* rules changed, set by inotify or a HUP signal */
1094 if (reload_config) {
1096 udev_rules_cleanup(&rules);
1097 udev_rules_init(udev, &rules, 1);
1100 /* forked child has returned */
1101 if (sigchilds_waiting) {
1102 sigchilds_waiting = 0;
1109 msg_queue_manager(udev);
1115 udev_rules_cleanup(&rules);
1118 if (signal_pipe[READ_END] >= 0)
1119 close(signal_pipe[READ_END]);
1120 if (signal_pipe[WRITE_END] >= 0)
1121 close(signal_pipe[WRITE_END]);
1123 udev_ctrl_unref(udev_ctrl);
1124 if (inotify_fd >= 0)
1126 if (uevent_netlink_sock >= 0)
1127 close(uevent_netlink_sock);