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/>.
34 #include <sys/select.h>
36 #include <sys/types.h>
37 #include <sys/socket.h>
40 #include <sys/ioctl.h>
41 #include <linux/types.h>
42 #include <linux/netlink.h>
44 #include <sys/inotify.h>
48 #include "udev_rules.h"
50 #define UDEVD_PRIORITY -4
51 #define UDEV_PRIORITY -2
53 /* maximum limit of forked childs */
54 #define UDEVD_MAX_CHILDS 256
58 static void log_fn(struct udev *udev, int priority,
59 const char *file, int line, const char *fn,
60 const char *format, va_list args)
63 fprintf(stderr, "[%d] %s: ", (int) getpid(), fn);
64 vfprintf(stderr, format, args);
66 vsyslog(priority, format, args);
70 struct udevd_uevent_msg {
72 struct list_head node;
81 unsigned long long seqnum;
85 char *envp[UEVENT_NUM_ENVP+1];
89 static int debug_trace;
90 static struct udev_rules rules;
91 static struct udev_ctrl *udev_ctrl;
92 static int uevent_netlink_sock = -1;
93 static int inotify_fd = -1;
95 static int signal_pipe[2] = {-1, -1};
96 static volatile int sigchilds_waiting;
97 static volatile int udev_exit;
98 static volatile int reload_config;
99 static int run_exec_q;
100 static int stop_exec_q;
101 static int max_childs;
102 static char udev_log_env[32];
104 static LIST_HEAD(exec_list);
105 static LIST_HEAD(running_list);
107 static void asmlinkage udev_event_sig_handler(int signum)
109 if (signum == SIGALRM)
113 static int udev_event_process(struct udevd_uevent_msg *msg)
115 struct sigaction act;
116 struct udevice *udevice;
120 /* set signal handlers */
121 memset(&act, 0x00, sizeof(act));
122 act.sa_handler = (void (*)(int)) udev_event_sig_handler;
123 sigemptyset (&act.sa_mask);
125 sigaction(SIGALRM, &act, NULL);
127 /* reset to default */
128 act.sa_handler = SIG_DFL;
129 sigaction(SIGINT, &act, NULL);
130 sigaction(SIGTERM, &act, NULL);
131 sigaction(SIGCHLD, &act, NULL);
132 sigaction(SIGHUP, &act, NULL);
134 /* trigger timeout to prevent hanging processes */
135 alarm(UDEV_EVENT_TIMEOUT);
137 /* reconstruct event environment from message */
138 for (i = 0; msg->envp[i]; i++)
139 putenv(msg->envp[i]);
141 udevice = udev_device_init(msg->udev);
144 strlcpy(udevice->action, msg->action, sizeof(udevice->action));
145 sysfs_device_set_values(udevice->udev, udevice->dev, msg->devpath, msg->subsystem, msg->driver);
146 udevice->devpath_old = msg->devpath_old;
147 udevice->devt = msg->devt;
149 retval = udev_device_event(&rules, udevice);
151 /* rules may change/disable the timeout */
152 if (udevice->event_timeout >= 0)
153 alarm(udevice->event_timeout);
155 /* run programs collected by RUN-key*/
156 if (retval == 0 && !udevice->ignore_device && udev_get_run(msg->udev))
157 retval = udev_rules_run(udevice);
159 udev_device_cleanup(udevice);
169 static void export_event_state(struct udevd_uevent_msg *msg, enum event_state state)
171 char filename[PATH_SIZE];
172 char filename_failed[PATH_SIZE];
175 /* location of queue file */
176 snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu", udev_get_dev_path(msg->udev), msg->seqnum);
178 /* location of failed file */
179 strlcpy(filename_failed, udev_get_dev_path(msg->udev), sizeof(filename_failed));
180 strlcat(filename_failed, "/", sizeof(filename_failed));
181 start = strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed));
182 strlcat(filename_failed, msg->devpath, sizeof(filename_failed));
183 path_encode(&filename_failed[start], sizeof(filename_failed) - start);
187 unlink(filename_failed);
188 delete_path(msg->udev, filename_failed);
189 create_path(msg->udev, filename);
190 udev_selinux_setfscreatecon(msg->udev, filename, S_IFLNK);
191 symlink(msg->devpath, filename);
192 udev_selinux_resetfscreatecon(msg->udev);
195 if (msg->devpath_old != NULL) {
196 /* "move" event - rename failed file to current name, do not delete failed */
197 char filename_failed_old[PATH_SIZE];
199 strlcpy(filename_failed_old, udev_get_dev_path(msg->udev), sizeof(filename_failed_old));
200 strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
201 start = strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old));
202 strlcat(filename_failed_old, msg->devpath_old, sizeof(filename_failed_old));
203 path_encode(&filename_failed_old[start], sizeof(filename) - start);
205 if (rename(filename_failed_old, filename_failed) == 0)
206 info(msg->udev, "renamed devpath, moved failed state of '%s' to %s'\n",
207 msg->devpath_old, msg->devpath);
209 unlink(filename_failed);
210 delete_path(msg->udev, filename_failed);
214 delete_path(msg->udev, filename);
217 /* move failed event to the failed directory */
218 create_path(msg->udev, filename_failed);
219 rename(filename, filename_failed);
221 /* clean up possibly empty queue directory */
222 delete_path(msg->udev, filename);
229 static void msg_queue_delete(struct udevd_uevent_msg *msg)
231 list_del(&msg->node);
233 /* mark as failed, if "add" event returns non-zero */
234 if (msg->exitstatus && strcmp(msg->action, "add") == 0)
235 export_event_state(msg, EVENT_FAILED);
237 export_event_state(msg, EVENT_FINISHED);
242 static void udev_event_run(struct udevd_uevent_msg *msg)
251 close(uevent_netlink_sock);
252 udev_ctrl_unref(udev_ctrl);
255 close(signal_pipe[READ_END]);
256 close(signal_pipe[WRITE_END]);
258 logging_init("udevd-event");
259 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
261 retval = udev_event_process(msg);
262 info(msg->udev, "seq %llu finished with %i\n", msg->seqnum, retval);
269 err(msg->udev, "fork of child failed: %s\n", strerror(errno));
270 msg_queue_delete(msg);
273 /* get SIGCHLD in main loop */
274 info(msg->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
275 msg->seqnum, pid, msg->action, msg->subsystem, time(NULL) - msg->queue_time);
280 static void msg_queue_insert(struct udevd_uevent_msg *msg)
282 char filename[PATH_SIZE];
285 msg->queue_time = time(NULL);
287 export_event_state(msg, EVENT_QUEUED);
288 info(msg->udev, "seq %llu queued, '%s' '%s'\n", msg->seqnum, msg->action, msg->subsystem);
290 strlcpy(filename, udev_get_dev_path(msg->udev), sizeof(filename));
291 strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
292 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
297 len = sprintf(str, "%llu\n", msg->seqnum);
302 /* run one event after the other in debug mode */
304 list_add_tail(&msg->node, &running_list);
306 waitpid(msg->pid, NULL, 0);
307 msg_queue_delete(msg);
311 /* run all events with a timeout set immediately */
312 if (msg->timeout != 0) {
313 list_add_tail(&msg->node, &running_list);
318 list_add_tail(&msg->node, &exec_list);
322 static int mem_size_mb(void)
326 long int memsize = -1;
328 f = fopen("/proc/meminfo", "r");
332 while (fgets(buf, sizeof(buf), f) != NULL) {
335 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
336 memsize = value / 1024;
345 static int compare_devpath(const char *running, const char *waiting)
349 for (i = 0; i < PATH_SIZE; i++) {
350 /* identical device event found */
351 if (running[i] == '\0' && waiting[i] == '\0')
354 /* parent device event found */
355 if (running[i] == '\0' && waiting[i] == '/')
358 /* child device event found */
359 if (running[i] == '/' && waiting[i] == '\0')
362 /* no matching event */
363 if (running[i] != waiting[i])
370 /* lookup event for identical, parent, child, or physical device */
371 static int devpath_busy(struct udevd_uevent_msg *msg, int limit)
373 struct udevd_uevent_msg *loop_msg;
374 int childs_count = 0;
376 /* check exec-queue which may still contain delayed events we depend on */
377 list_for_each_entry(loop_msg, &exec_list, node) {
378 /* skip ourself and all later events */
379 if (loop_msg->seqnum >= msg->seqnum)
382 /* check our old name */
383 if (msg->devpath_old != NULL)
384 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
387 /* check identical, parent, or child device event */
388 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
389 dbg(msg->udev, "%llu, device event still pending %llu (%s)\n",
390 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
394 /* check for our major:minor number */
395 if (msg->devt && loop_msg->devt == msg->devt &&
396 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
397 dbg(msg->udev, "%llu, device event still pending %llu (%d:%d)\n", msg->seqnum,
398 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
402 /* check physical device event (special case of parent) */
403 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
404 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
405 dbg(msg->udev, "%llu, physical device event still pending %llu (%s)\n",
406 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
411 /* check run queue for still running events */
412 list_for_each_entry(loop_msg, &running_list, node) {
415 if (childs_count++ >= limit) {
416 info(msg->udev, "%llu, maximum number (%i) of childs reached\n", msg->seqnum, childs_count);
420 /* check our old name */
421 if (msg->devpath_old != NULL)
422 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
425 /* check identical, parent, or child device event */
426 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
427 dbg(msg->udev, "%llu, device event still running %llu (%s)\n",
428 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
432 /* check for our major:minor number */
433 if (msg->devt && loop_msg->devt == msg->devt &&
434 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
435 dbg(msg->udev, "%llu, device event still running %llu (%d:%d)\n", msg->seqnum,
436 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
440 /* check physical device event (special case of parent) */
441 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
442 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
443 dbg(msg->udev, "%llu, physical device event still running %llu (%s)\n",
444 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
451 /* serializes events for the identical and parent and child devices */
452 static void msg_queue_manager(struct udev *udev)
454 struct udevd_uevent_msg *loop_msg;
455 struct udevd_uevent_msg *tmp_msg;
457 if (list_empty(&exec_list))
460 list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, node) {
461 /* serialize and wait for parent or child events */
462 if (devpath_busy(loop_msg, max_childs) != 0) {
463 dbg(udev, "delay seq %llu (%s)\n", loop_msg->seqnum, loop_msg->devpath);
467 /* move event to run list */
468 list_move_tail(&loop_msg->node, &running_list);
469 udev_event_run(loop_msg);
470 dbg(udev, "moved seq %llu to running list\n", loop_msg->seqnum);
474 static struct udevd_uevent_msg *get_msg_from_envbuf(struct udev *udev, const char *buf, int buf_size)
478 struct udevd_uevent_msg *msg;
479 char *physdevdriver_key = NULL;
483 msg = malloc(sizeof(struct udevd_uevent_msg) + buf_size);
486 memset(msg, 0x00, sizeof(struct udevd_uevent_msg) + buf_size);
489 /* copy environment buffer and reconstruct envp */
490 memcpy(msg->envbuf, buf, buf_size);
492 for (i = 0; (bufpos < buf_size) && (i < UEVENT_NUM_ENVP-2); i++) {
496 key = &msg->envbuf[bufpos];
497 keylen = strlen(key);
499 bufpos += keylen + 1;
500 dbg(udev, "add '%s' to msg.envp[%i]\n", msg->envp[i], i);
502 /* remember some keys for further processing */
503 if (strncmp(key, "ACTION=", 7) == 0)
504 msg->action = &key[7];
505 else if (strncmp(key, "DEVPATH=", 8) == 0)
506 msg->devpath = &key[8];
507 else if (strncmp(key, "SUBSYSTEM=", 10) == 0)
508 msg->subsystem = &key[10];
509 else if (strncmp(key, "DRIVER=", 7) == 0)
510 msg->driver = &key[7];
511 else if (strncmp(key, "SEQNUM=", 7) == 0)
512 msg->seqnum = strtoull(&key[7], NULL, 10);
513 else if (strncmp(key, "DEVPATH_OLD=", 12) == 0)
514 msg->devpath_old = &key[12];
515 else if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
516 msg->physdevpath = &key[12];
517 else if (strncmp(key, "PHYSDEVDRIVER=", 14) == 0)
518 physdevdriver_key = key;
519 else if (strncmp(key, "MAJOR=", 6) == 0)
520 maj = strtoull(&key[6], NULL, 10);
521 else if (strncmp(key, "MINOR=", 6) == 0)
522 min = strtoull(&key[6], NULL, 10);
523 else if (strncmp(key, "TIMEOUT=", 8) == 0)
524 msg->timeout = strtoull(&key[8], NULL, 10);
526 msg->devt = makedev(maj, min);
527 msg->envp[i++] = "UDEVD_EVENT=1";
529 if (msg->driver == NULL && msg->physdevpath == NULL && physdevdriver_key != NULL) {
530 /* for older kernels DRIVER is empty for a bus device, export PHYSDEVDRIVER as DRIVER */
531 msg->envp[i++] = &physdevdriver_key[7];
532 msg->driver = &physdevdriver_key[14];
537 if (msg->devpath == NULL || msg->action == NULL) {
538 info(udev, "DEVPATH or ACTION missing, ignore message\n");
545 /* receive the udevd message from userspace */
546 static void handle_ctrl_msg(struct udev_ctrl *uctrl)
548 struct udev *udev = udev_ctrl_get_udev(uctrl);
549 struct udev_ctrl_msg *ctrl_msg;
553 ctrl_msg = udev_ctrl_receive_msg(uctrl);
554 if (ctrl_msg == NULL)
557 i = udev_ctrl_get_set_log_level(ctrl_msg);
559 info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i);
560 udev_set_log_priority(udev, i);
561 sprintf(udev_log_env, "UDEV_LOG=%i", i);
562 putenv(udev_log_env);
565 if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) {
566 info(udev, "udevd message (STOP_EXEC_QUEUE) received\n");
570 if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) {
571 info(udev, "udevd message (START_EXEC_QUEUE) received\n");
573 msg_queue_manager(udev);
576 if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) {
577 info(udev, "udevd message (RELOAD_RULES) received\n");
581 str = udev_ctrl_get_set_env(ctrl_msg);
583 char *key = strdup(str);
586 val = strchr(str, '=');
590 if (val[0] == '\0') {
591 info(udev, "udevd message (ENV) received, unset '%s'\n", key);
594 info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val);
598 err(udev, "wrong key format '%s'\n", key);
603 i = udev_ctrl_get_set_max_childs(ctrl_msg);
605 info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i);
609 udev_ctrl_msg_unref(ctrl_msg);
612 /* receive the kernel user event message and do some sanity checks */
613 static struct udevd_uevent_msg *get_netlink_msg(struct udev *udev)
615 struct udevd_uevent_msg *msg;
618 static char buffer[UEVENT_BUFFER_SIZE+512];
621 size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
624 err(udev, "unable to receive kernel netlink message: %s\n", strerror(errno));
628 if ((size_t)size > sizeof(buffer)-1)
629 size = sizeof(buffer)-1;
631 dbg(udev, "uevent_size=%zi\n", size);
633 /* start of event payload */
634 bufpos = strlen(buffer)+1;
635 msg = get_msg_from_envbuf(udev, &buffer[bufpos], size-bufpos);
639 /* validate message */
640 pos = strchr(buffer, '@');
642 err(udev, "invalid uevent '%s'\n", buffer);
648 if (msg->action == NULL) {
649 info(udev, "no ACTION in payload found, skip event '%s'\n", buffer);
654 if (strcmp(msg->action, buffer) != 0) {
655 err(udev, "ACTION in payload does not match uevent, skip event '%s'\n", buffer);
663 static void asmlinkage sig_handler(int signum)
671 /* set flag, then write to pipe if needed */
672 sigchilds_waiting = 1;
679 /* write to pipe, which will wakeup select() in our mainloop */
680 write(signal_pipe[WRITE_END], "", 1);
683 static void udev_done(int pid, int exitstatus)
685 /* find msg associated with pid and delete it */
686 struct udevd_uevent_msg *msg;
688 list_for_each_entry(msg, &running_list, node) {
689 if (msg->pid == pid) {
690 info(msg->udev, "seq %llu, pid [%d] exit with %i, %ld seconds old\n", msg->seqnum, msg->pid,
691 exitstatus, time(NULL) - msg->queue_time);
692 msg->exitstatus = exitstatus;
693 msg_queue_delete(msg);
695 /* there may be events waiting with the same devpath */
702 static void reap_sigchilds(void)
708 pid = waitpid(-1, &status, WNOHANG);
711 if (WIFEXITED(status))
712 status = WEXITSTATUS(status);
713 else if (WIFSIGNALED(status))
714 status = WTERMSIG(status) + 128;
717 udev_done(pid, status);
721 static int init_uevent_netlink_sock(struct udev *udev)
723 struct sockaddr_nl snl;
724 const int buffersize = 16 * 1024 * 1024;
727 memset(&snl, 0x00, sizeof(struct sockaddr_nl));
728 snl.nl_family = AF_NETLINK;
729 snl.nl_pid = getpid();
732 uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
733 if (uevent_netlink_sock == -1) {
734 err(udev, "error getting socket: %s\n", strerror(errno));
738 /* set receive buffersize */
739 setsockopt(uevent_netlink_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
741 retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
743 err(udev, "bind failed: %s\n", strerror(errno));
744 close(uevent_netlink_sock);
745 uevent_netlink_sock = -1;
751 static void export_initial_seqnum(struct udev *udev)
753 char filename[PATH_SIZE];
758 strlcpy(filename, udev_get_sys_path(udev), sizeof(filename));
759 strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
760 fd = open(filename, O_RDONLY);
762 len = read(fd, seqnum, sizeof(seqnum)-1);
766 strcpy(seqnum, "0\n");
769 strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
770 strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename));
771 create_path(udev, filename);
772 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
774 write(fd, seqnum, len);
779 int main(int argc, char *argv[])
784 struct sigaction act;
788 static const struct option options[] = {
789 { "daemon", 0, NULL, 'd' },
790 { "debug-trace", 0, NULL, 't' },
791 { "debug", 0, NULL, 'D' },
792 { "help", 0, NULL, 'h' },
793 { "version", 0, NULL, 'V' },
803 logging_init("udevd");
804 udev_set_log_fn(udev, log_fn);
805 dbg(udev, "version %s\n", VERSION);
810 option = getopt_long(argc, argv, "dDthV", options, NULL);
823 if (udev_get_log_priority(udev) < LOG_INFO)
824 udev_set_log_priority(udev, LOG_INFO);
827 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
830 printf("%s\n", VERSION);
838 fprintf(stderr, "root privileges required\n");
839 err(udev, "root privileges required\n");
843 /* make sure std{in,out,err} fd's are in a sane state */
844 fd = open("/dev/null", O_RDWR);
846 fprintf(stderr, "cannot open /dev/null\n");
847 err(udev, "cannot open /dev/null\n");
849 if (fd > STDIN_FILENO)
850 dup2(fd, STDIN_FILENO);
851 if (write(STDOUT_FILENO, 0, 0) < 0)
852 dup2(fd, STDOUT_FILENO);
853 if (write(STDERR_FILENO, 0, 0) < 0)
854 dup2(fd, STDERR_FILENO);
856 /* init control socket, bind() ensures, that only one udevd instance is running */
857 udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
858 if (udev_ctrl == NULL) {
859 fprintf(stderr, "error initializing control socket");
860 err(udev, "error initializing udevd socket");
865 if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
866 fprintf(stderr, "error binding control socket, seems udevd is already running\n");
867 err(udev, "error binding control socket, seems udevd is already running\n");
872 if (init_uevent_netlink_sock(udev) < 0) {
873 fprintf(stderr, "error initializing netlink socket\n");
874 err(udev, "error initializing netlink socket\n");
879 retval = pipe(signal_pipe);
881 err(udev, "error getting pipes: %s\n", strerror(errno));
885 retval = fcntl(signal_pipe[READ_END], F_GETFL, 0);
887 err(udev, "error fcntl on read pipe: %s\n", strerror(errno));
890 retval = fcntl(signal_pipe[READ_END], F_SETFL, retval | O_NONBLOCK);
892 err(udev, "error fcntl on read pipe: %s\n", strerror(errno));
896 retval = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
898 err(udev, "error fcntl on write pipe: %s\n", strerror(errno));
901 retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
903 err(udev, "error fcntl on write pipe: %s\n", strerror(errno));
907 /* parse the rules and keep them in memory */
909 udev_rules_init(udev, &rules, 1);
911 export_initial_seqnum(udev);
919 dbg(udev, "daemonized fork running\n");
922 err(udev, "fork of daemon failed: %s\n", strerror(errno));
926 dbg(udev, "child [%u] running, parent exits\n", pid);
932 /* redirect std{out,err} */
934 dup2(fd, STDOUT_FILENO);
935 dup2(fd, STDERR_FILENO);
937 if (fd > STDERR_FILENO)
940 /* set scheduling priority for the daemon */
941 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
947 /* OOM_DISABLE == -17 */
948 fd = open("/proc/self/oom_adj", O_RDWR);
950 err(udev, "error disabling OOM: %s\n", strerror(errno));
956 fd = open("/dev/kmsg", O_WRONLY);
958 const char *str = "<6>udevd version " VERSION " started\n";
960 write(fd, str, strlen(str));
964 /* set signal handlers */
965 memset(&act, 0x00, sizeof(struct sigaction));
966 act.sa_handler = (void (*)(int)) sig_handler;
967 sigemptyset(&act.sa_mask);
968 act.sa_flags = SA_RESTART;
969 sigaction(SIGINT, &act, NULL);
970 sigaction(SIGTERM, &act, NULL);
971 sigaction(SIGCHLD, &act, NULL);
972 sigaction(SIGHUP, &act, NULL);
974 /* watch rules directory */
975 inotify_fd = inotify_init();
976 if (inotify_fd >= 0) {
977 if (udev_get_rules_path(udev) != NULL) {
978 inotify_add_watch(inotify_fd, udev_get_rules_path(udev),
979 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
981 char filename[PATH_MAX];
983 inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d",
984 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
985 inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d",
986 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
988 /* watch dynamic rules directory */
989 strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
990 strlcat(filename, "/.udev/rules.d", sizeof(filename));
991 inotify_add_watch(inotify_fd, filename,
992 IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
994 } else if (errno == ENOSYS)
995 err(udev, "the kernel does not support inotify, udevd can't monitor rules file changes\n");
997 err(udev, "inotify_init failed: %s\n", strerror(errno));
999 /* maximum limit of forked childs */
1000 value = getenv("UDEVD_MAX_CHILDS");
1002 max_childs = strtoul(value, NULL, 10);
1004 int memsize = mem_size_mb();
1006 max_childs = 128 + (memsize / 4);
1008 max_childs = UDEVD_MAX_CHILDS;
1010 info(udev, "initialize max_childs to %u\n", max_childs);
1012 /* clear environment for forked event processes */
1015 /* export log_priority , as called programs may want to follow that setting */
1016 sprintf(udev_log_env, "UDEV_LOG=%i", udev_get_log_priority(udev));
1017 putenv(udev_log_env);
1021 maxfd = udev_ctrl_get_fd(udev_ctrl);
1022 maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
1023 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
1024 maxfd = UDEV_MAX(maxfd, inotify_fd);
1026 while (!udev_exit) {
1027 struct udevd_uevent_msg *msg;
1031 FD_SET(signal_pipe[READ_END], &readfds);
1032 FD_SET(udev_ctrl_get_fd(udev_ctrl), &readfds);
1033 FD_SET(uevent_netlink_sock, &readfds);
1034 if (inotify_fd >= 0)
1035 FD_SET(inotify_fd, &readfds);
1037 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
1040 err(udev, "error in select: %s\n", strerror(errno));
1044 /* get control message */
1045 if (FD_ISSET(udev_ctrl_get_fd(udev_ctrl), &readfds))
1046 handle_ctrl_msg(udev_ctrl);
1048 /* get netlink message */
1049 if (FD_ISSET(uevent_netlink_sock, &readfds)) {
1050 msg = get_netlink_msg(udev);
1052 msg_queue_insert(msg);
1055 /* received a signal, clear our notification pipe */
1056 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
1059 read(signal_pipe[READ_END], &buf, sizeof(buf));
1062 /* rules directory inotify watch */
1063 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
1066 /* discard all possible events, we can just reload the config */
1067 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
1071 buf = malloc(nbytes);
1073 err(udev, "error getting buffer for inotify, disable watching\n");
1077 read(inotify_fd, buf, nbytes);
1082 /* rules changed, set by inotify or a HUP signal */
1083 if (reload_config) {
1085 udev_rules_cleanup(&rules);
1086 udev_rules_init(udev, &rules, 1);
1089 /* forked child has returned */
1090 if (sigchilds_waiting) {
1091 sigchilds_waiting = 0;
1098 msg_queue_manager(udev);
1104 udev_rules_cleanup(&rules);
1107 if (signal_pipe[READ_END] >= 0)
1108 close(signal_pipe[READ_END]);
1109 if (signal_pipe[WRITE_END] >= 0)
1110 close(signal_pipe[WRITE_END]);
1112 udev_ctrl_unref(udev_ctrl);
1113 if (inotify_fd >= 0)
1115 if (uevent_netlink_sock >= 0)
1116 close(uevent_netlink_sock);