2 * Copyright (C) 2004-2006 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 it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation version 2 of the License.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
33 #include <sys/select.h>
35 #include <sys/types.h>
36 #include <sys/socket.h>
39 #include <sys/ioctl.h>
40 #include <linux/types.h>
41 #include <linux/netlink.h>
44 #include "udev_rules.h"
46 #include "udev_selinux.h"
48 static int debug_trace;
51 static struct udev_rules rules;
52 static int udevd_sock = -1;
53 static int uevent_netlink_sock = -1;
54 static int inotify_fd = -1;
57 static int signal_pipe[2] = {-1, -1};
58 static volatile int sigchilds_waiting;
59 static volatile int udev_exit;
60 static volatile int reload_config;
61 static int run_exec_q;
62 static int stop_exec_q;
63 static int max_childs;
64 static int max_childs_running;
65 static char udev_log[32];
67 static LIST_HEAD(exec_list);
68 static LIST_HEAD(running_list);
72 void log_message(int priority, const char *format, ...)
76 if (priority > udev_log_priority)
79 va_start(args, format);
81 printf("[%d] ", (int) getpid());
82 vprintf(format, args);
84 vsyslog(priority, format, args);
90 static void asmlinkage udev_event_sig_handler(int signum)
92 if (signum == SIGALRM)
96 static int udev_event_process(struct udevd_uevent_msg *msg)
103 /* set signal handlers */
104 memset(&act, 0x00, sizeof(act));
105 act.sa_handler = (void (*)(int)) udev_event_sig_handler;
106 sigemptyset (&act.sa_mask);
108 sigaction(SIGALRM, &act, NULL);
110 /* reset to default */
111 act.sa_handler = SIG_DFL;
112 sigaction(SIGINT, &act, NULL);
113 sigaction(SIGTERM, &act, NULL);
114 sigaction(SIGCHLD, &act, NULL);
115 sigaction(SIGHUP, &act, NULL);
117 /* trigger timeout to prevent hanging processes */
118 alarm(UDEV_EVENT_TIMEOUT);
120 /* reconstruct event environment from message */
121 for (i = 0; msg->envp[i]; i++)
122 putenv(msg->envp[i]);
124 udev = udev_device_init(NULL);
127 strlcpy(udev->action, msg->action, sizeof(udev->action));
128 sysfs_device_set_values(udev->dev, msg->devpath, msg->subsystem, msg->driver);
129 udev->devpath_old = msg->devpath_old;
130 udev->devt = msg->devt;
132 retval = udev_device_event(&rules, udev);
134 /* rules may change/disable the timeout */
135 if (udev->event_timeout >= 0)
136 alarm(udev->event_timeout);
138 /* run programs collected by RUN-key*/
139 if (retval == 0 && !udev->ignore_device && udev_run)
140 retval = udev_rules_run(udev);
142 udev_device_cleanup(udev);
152 static void export_event_state(struct udevd_uevent_msg *msg, enum event_state state)
154 char filename[PATH_SIZE];
155 char filename_failed[PATH_SIZE];
158 /* location of queue file */
159 snprintf(filename, sizeof(filename), "%s/"EVENT_QUEUE_DIR"/%llu", udev_root, msg->seqnum);
161 /* location of failed file */
162 strlcpy(filename_failed, udev_root, sizeof(filename_failed));
163 strlcat(filename_failed, "/", sizeof(filename_failed));
164 start = strlcat(filename_failed, EVENT_FAILED_DIR"/", sizeof(filename_failed));
165 strlcat(filename_failed, msg->devpath, sizeof(filename_failed));
166 path_encode(&filename_failed[start], sizeof(filename_failed) - start);
170 unlink(filename_failed);
171 delete_path(filename_failed);
173 create_path(filename);
174 selinux_setfscreatecon(filename, NULL, S_IFLNK);
175 symlink(msg->devpath, filename);
176 selinux_resetfscreatecon();
179 if (msg->devpath_old != NULL) {
180 /* "move" event - rename failed file to current name, do not delete failed */
181 char filename_failed_old[PATH_SIZE];
183 strlcpy(filename_failed_old, udev_root, sizeof(filename_failed_old));
184 strlcat(filename_failed_old, "/", sizeof(filename_failed_old));
185 start = strlcat(filename_failed_old, EVENT_FAILED_DIR"/", sizeof(filename_failed_old));
186 strlcat(filename_failed_old, msg->devpath_old, sizeof(filename_failed_old));
187 path_encode(&filename_failed_old[start], sizeof(filename) - start);
189 if (rename(filename_failed_old, filename_failed) == 0)
190 info("renamed devpath, moved failed state of '%s' to %s'\n",
191 msg->devpath_old, msg->devpath);
193 unlink(filename_failed);
194 delete_path(filename_failed);
198 delete_path(filename);
201 /* move failed event to the failed directory */
202 create_path(filename_failed);
203 rename(filename, filename_failed);
205 /* clean up possibly empty queue directory */
206 delete_path(filename);
213 static void msg_queue_delete(struct udevd_uevent_msg *msg)
215 list_del(&msg->node);
217 /* mark as failed, if "add" event returns non-zero */
218 if (msg->exitstatus && strcmp(msg->action, "add") == 0)
219 export_event_state(msg, EVENT_FAILED);
221 export_event_state(msg, EVENT_FINISHED);
226 static void udev_event_run(struct udevd_uevent_msg *msg)
235 close(uevent_netlink_sock);
239 close(signal_pipe[READ_END]);
240 close(signal_pipe[WRITE_END]);
243 logging_init("udevd-event");
244 setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
246 retval = udev_event_process(msg);
247 info("seq %llu finished with %i\n", msg->seqnum, retval);
254 err("fork of child failed: %s\n", strerror(errno));
255 msg_queue_delete(msg);
258 /* get SIGCHLD in main loop */
259 info("seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n",
260 msg->seqnum, pid, msg->action, msg->subsystem, time(NULL) - msg->queue_time);
265 static void msg_queue_insert(struct udevd_uevent_msg *msg)
267 char filename[PATH_SIZE];
270 msg->queue_time = time(NULL);
272 export_event_state(msg, EVENT_QUEUED);
273 info("seq %llu queued, '%s' '%s'\n", msg->seqnum, msg->action, msg->subsystem);
275 strlcpy(filename, udev_root, sizeof(filename));
276 strlcat(filename, "/" EVENT_SEQNUM, sizeof(filename));
277 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
282 len = sprintf(str, "%llu\n", msg->seqnum);
287 /* run one event after the other in debug mode */
289 list_add_tail(&msg->node, &running_list);
291 waitpid(msg->pid, NULL, 0);
292 msg_queue_delete(msg);
296 /* run all events with a timeout set immediately */
297 if (msg->timeout != 0) {
298 list_add_tail(&msg->node, &running_list);
303 list_add_tail(&msg->node, &exec_list);
307 static int mem_size_mb(void)
311 long int memsize = -1;
313 f = fopen("/proc/meminfo", "r");
317 while (fgets(buf, sizeof(buf), f) != NULL) {
320 if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) {
321 memsize = value / 1024;
330 static int cpu_count(void)
336 f = fopen("/proc/stat", "r");
340 while (fgets(buf, sizeof(buf), f) != NULL) {
341 if (strncmp(buf, "cpu", 3) == 0 && isdigit(buf[3]))
351 static int running_processes(void)
357 f = fopen("/proc/stat", "r");
361 while (fgets(buf, sizeof(buf), f) != NULL) {
364 if (sscanf(buf, "procs_running %u", &value) == 1) {
374 /* return the number of process es in our session, count only until limit */
375 static int running_processes_in_session(pid_t session, int limit)
381 dir = opendir("/proc");
385 /* read process info from /proc */
386 for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
392 pid_t ppid, pgrp, sess;
395 if (!isdigit(dent->d_name[0]))
398 snprintf(procdir, sizeof(procdir), "/proc/%s/stat", dent->d_name);
399 procdir[sizeof(procdir)-1] = '\0';
401 f = open(procdir, O_RDONLY);
405 len = read(f, line, sizeof(line)-1);
413 /* skip ugly program name */
414 pos = strrchr(line, ')') + 2;
418 if (sscanf(pos, "%c %d %d %d ", &state, &ppid, &pgrp, &sess) != 4)
421 /* count only processes in our session */
425 /* count only running, no sleeping processes */
430 if (limit > 0 && running >= limit)
438 static int compare_devpath(const char *running, const char *waiting)
442 for (i = 0; i < PATH_SIZE; i++) {
443 /* identical device event found */
444 if (running[i] == '\0' && waiting[i] == '\0')
447 /* parent device event found */
448 if (running[i] == '\0' && waiting[i] == '/')
451 /* child device event found */
452 if (running[i] == '/' && waiting[i] == '\0')
455 /* no matching event */
456 if (running[i] != waiting[i])
463 /* lookup event for identical, parent, child, or physical device */
464 static int devpath_busy(struct udevd_uevent_msg *msg, int limit)
466 struct udevd_uevent_msg *loop_msg;
467 int childs_count = 0;
469 /* check exec-queue which may still contain delayed events we depend on */
470 list_for_each_entry(loop_msg, &exec_list, node) {
471 /* skip ourself and all later events */
472 if (loop_msg->seqnum >= msg->seqnum)
475 /* check our old name */
476 if (msg->devpath_old != NULL)
477 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
480 /* check identical, parent, or child device event */
481 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
482 dbg("%llu, device event still pending %llu (%s)\n",
483 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
487 /* check for our major:minor number */
488 if (msg->devt && loop_msg->devt == msg->devt &&
489 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
490 dbg("%llu, device event still pending %llu (%d:%d)\n", msg->seqnum,
491 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
495 /* check physical device event (special case of parent) */
496 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
497 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
498 dbg("%llu, physical device event still pending %llu (%s)\n",
499 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
504 /* check run queue for still running events */
505 list_for_each_entry(loop_msg, &running_list, node) {
506 if (limit && childs_count++ > limit) {
507 dbg("%llu, maximum number (%i) of childs reached\n", msg->seqnum, childs_count);
511 /* check our old name */
512 if (msg->devpath_old != NULL)
513 if (strcmp(loop_msg->devpath , msg->devpath_old) == 0)
516 /* check identical, parent, or child device event */
517 if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
518 dbg("%llu, device event still running %llu (%s)\n",
519 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
523 /* check for our major:minor number */
524 if (msg->devt && loop_msg->devt == msg->devt &&
525 strcmp(msg->subsystem, loop_msg->subsystem) == 0) {
526 dbg("%llu, device event still running %llu (%d:%d)\n", msg->seqnum,
527 loop_msg->seqnum, major(loop_msg->devt), minor(loop_msg->devt));
531 /* check physical device event (special case of parent) */
532 if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
533 if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
534 dbg("%llu, physical device event still running %llu (%s)\n",
535 msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
542 /* serializes events for the identical and parent and child devices */
543 static void msg_queue_manager(void)
545 struct udevd_uevent_msg *loop_msg;
546 struct udevd_uevent_msg *tmp_msg;
549 if (list_empty(&exec_list))
552 running = running_processes();
553 dbg("%d processes runnning on system\n", running);
555 running = max_childs_running;
557 list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, node) {
558 /* check running processes in our session and possibly throttle */
559 if (running >= max_childs_running) {
560 running = running_processes_in_session(sid, max_childs_running+10);
561 dbg("at least %d processes running in session\n", running);
562 if (running >= max_childs_running) {
563 dbg("delay seq %llu, too many processes already running\n", loop_msg->seqnum);
568 /* serialize and wait for parent or child events */
569 if (devpath_busy(loop_msg, max_childs) != 0) {
570 dbg("delay seq %llu (%s)\n", loop_msg->seqnum, loop_msg->devpath);
574 /* move event to run list */
575 list_move_tail(&loop_msg->node, &running_list);
576 udev_event_run(loop_msg);
578 dbg("moved seq %llu to running list\n", loop_msg->seqnum);
582 static struct udevd_uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size)
586 struct udevd_uevent_msg *msg;
587 char *physdevdriver_key = NULL;
591 msg = malloc(sizeof(struct udevd_uevent_msg) + buf_size);
594 memset(msg, 0x00, sizeof(struct udevd_uevent_msg) + buf_size);
596 /* copy environment buffer and reconstruct envp */
597 memcpy(msg->envbuf, buf, buf_size);
599 for (i = 0; (bufpos < buf_size) && (i < UEVENT_NUM_ENVP-2); i++) {
603 key = &msg->envbuf[bufpos];
604 keylen = strlen(key);
606 bufpos += keylen + 1;
607 dbg("add '%s' to msg.envp[%i]\n", msg->envp[i], i);
609 /* remember some keys for further processing */
610 if (strncmp(key, "ACTION=", 7) == 0)
611 msg->action = &key[7];
612 else if (strncmp(key, "DEVPATH=", 8) == 0)
613 msg->devpath = &key[8];
614 else if (strncmp(key, "SUBSYSTEM=", 10) == 0)
615 msg->subsystem = &key[10];
616 else if (strncmp(key, "DRIVER=", 7) == 0)
617 msg->driver = &key[7];
618 else if (strncmp(key, "SEQNUM=", 7) == 0)
619 msg->seqnum = strtoull(&key[7], NULL, 10);
620 else if (strncmp(key, "DEVPATH_OLD=", 12) == 0)
621 msg->devpath_old = &key[12];
622 else if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
623 msg->physdevpath = &key[12];
624 else if (strncmp(key, "PHYSDEVDRIVER=", 14) == 0)
625 physdevdriver_key = key;
626 else if (strncmp(key, "MAJOR=", 6) == 0)
627 maj = strtoull(&key[6], NULL, 10);
628 else if (strncmp(key, "MINOR=", 6) == 0)
629 min = strtoull(&key[6], NULL, 10);
630 else if (strncmp(key, "TIMEOUT=", 8) == 0)
631 msg->timeout = strtoull(&key[8], NULL, 10);
633 msg->devt = makedev(maj, min);
634 msg->envp[i++] = "UDEVD_EVENT=1";
636 if (msg->driver == NULL && msg->physdevpath == NULL && physdevdriver_key != NULL) {
637 /* for older kernels DRIVER is empty for a bus device, export PHYSDEVDRIVER as DRIVER */
638 msg->envp[i++] = &physdevdriver_key[7];
639 msg->driver = &physdevdriver_key[14];
644 if (msg->devpath == NULL || msg->action == NULL) {
645 info("DEVPATH or ACTION missing, ignore message\n");
652 /* receive the udevd message from userspace */
653 static void get_ctrl_msg(void)
655 struct udevd_ctrl_msg ctrl_msg;
658 struct cmsghdr *cmsg;
661 char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
665 memset(&ctrl_msg, 0x00, sizeof(struct udevd_ctrl_msg));
666 iov.iov_base = &ctrl_msg;
667 iov.iov_len = sizeof(struct udevd_ctrl_msg);
669 memset(&smsg, 0x00, sizeof(struct msghdr));
672 smsg.msg_control = cred_msg;
673 smsg.msg_controllen = sizeof(cred_msg);
675 size = recvmsg(udevd_sock, &smsg, 0);
678 err("unable to receive user udevd message: %s\n", strerror(errno));
681 cmsg = CMSG_FIRSTHDR(&smsg);
682 cred = (struct ucred *) CMSG_DATA(cmsg);
684 if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
685 err("no sender credentials received, message ignored\n");
689 if (cred->uid != 0) {
690 err("sender uid=%i, message ignored\n", cred->uid);
694 if (strncmp(ctrl_msg.magic, UDEVD_CTRL_MAGIC, sizeof(UDEVD_CTRL_MAGIC)) != 0 ) {
695 err("message magic '%s' doesn't match, ignore it\n", ctrl_msg.magic);
699 switch (ctrl_msg.type) {
701 pos = strchr(ctrl_msg.buf, '=');
703 err("wrong key format '%s'\n", ctrl_msg.buf);
707 if (pos[1] == '\0') {
708 info("udevd message (ENV) received, unset '%s'\n", ctrl_msg.buf);
709 unsetenv(ctrl_msg.buf);
711 info("udevd message (ENV) received, set '%s=%s'\n", ctrl_msg.buf, &pos[1]);
712 setenv(ctrl_msg.buf, &pos[1], 1);
715 case UDEVD_CTRL_STOP_EXEC_QUEUE:
716 info("udevd message (STOP_EXEC_QUEUE) received\n");
719 case UDEVD_CTRL_START_EXEC_QUEUE:
720 info("udevd message (START_EXEC_QUEUE) received\n");
724 case UDEVD_CTRL_SET_LOG_LEVEL:
725 intval = (int *) ctrl_msg.buf;
726 info("udevd message (SET_LOG_PRIORITY) received, udev_log_priority=%i\n", *intval);
727 udev_log_priority = *intval;
728 sprintf(udev_log, "UDEV_LOG=%i", udev_log_priority);
731 case UDEVD_CTRL_SET_MAX_CHILDS:
732 intval = (int *) ctrl_msg.buf;
733 info("udevd message (UDEVD_SET_MAX_CHILDS) received, max_childs=%i\n", *intval);
734 max_childs = *intval;
736 case UDEVD_CTRL_SET_MAX_CHILDS_RUNNING:
737 intval = (int *) ctrl_msg.buf;
738 info("udevd message (UDEVD_SET_MAX_CHILDS_RUNNING) received, max_childs=%i\n", *intval);
739 max_childs_running = *intval;
741 case UDEVD_CTRL_RELOAD_RULES:
742 info("udevd message (RELOAD_RULES) received\n");
746 err("unknown control message type\n");
750 /* receive the kernel user event message and do some sanity checks */
751 static struct udevd_uevent_msg *get_netlink_msg(void)
753 struct udevd_uevent_msg *msg;
756 static char buffer[UEVENT_BUFFER_SIZE+512];
759 size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
762 err("unable to receive kernel netlink message: %s\n", strerror(errno));
766 if ((size_t)size > sizeof(buffer)-1)
767 size = sizeof(buffer)-1;
769 dbg("uevent_size=%zi\n", size);
771 /* start of event payload */
772 bufpos = strlen(buffer)+1;
773 msg = get_msg_from_envbuf(&buffer[bufpos], size-bufpos);
777 /* validate message */
778 pos = strchr(buffer, '@');
780 err("invalid uevent '%s'\n", buffer);
786 if (msg->action == NULL) {
787 info("no ACTION in payload found, skip event '%s'\n", buffer);
792 if (strcmp(msg->action, buffer) != 0) {
793 err("ACTION in payload does not match uevent, skip event '%s'\n", buffer);
801 static void asmlinkage sig_handler(int signum)
809 /* set flag, then write to pipe if needed */
810 sigchilds_waiting = 1;
817 /* write to pipe, which will wakeup select() in our mainloop */
818 write(signal_pipe[WRITE_END], "", 1);
821 static void udev_done(int pid, int exitstatus)
823 /* find msg associated with pid and delete it */
824 struct udevd_uevent_msg *msg;
826 list_for_each_entry(msg, &running_list, node) {
827 if (msg->pid == pid) {
828 info("seq %llu, pid [%d] exit with %i, %ld seconds old\n", msg->seqnum, msg->pid,
829 exitstatus, time(NULL) - msg->queue_time);
830 msg->exitstatus = exitstatus;
831 msg_queue_delete(msg);
833 /* there may be events waiting with the same devpath */
840 static void reap_sigchilds(void)
846 pid = waitpid(-1, &status, WNOHANG);
849 if (WIFEXITED(status))
850 status = WEXITSTATUS(status);
851 else if (WIFSIGNALED(status))
852 status = WTERMSIG(status) + 128;
855 udev_done(pid, status);
859 static int init_udevd_socket(void)
861 struct sockaddr_un saddr;
863 const int feature_on = 1;
866 memset(&saddr, 0x00, sizeof(saddr));
867 saddr.sun_family = AF_LOCAL;
868 /* use abstract namespace for socket path */
869 strcpy(&saddr.sun_path[1], UDEVD_CTRL_SOCK_PATH);
870 addrlen = offsetof(struct sockaddr_un, sun_path) + 1 + strlen(&saddr.sun_path[1]);
872 udevd_sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
873 if (udevd_sock == -1) {
874 err("error getting socket: %s\n", strerror(errno));
878 /* the bind takes care of ensuring only one copy running */
879 retval = bind(udevd_sock, (struct sockaddr *) &saddr, addrlen);
881 err("bind failed: %s\n", strerror(errno));
887 /* enable receiving of the sender credentials */
888 setsockopt(udevd_sock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on));
893 static int init_uevent_netlink_sock(void)
895 struct sockaddr_nl snl;
896 const int buffersize = 16 * 1024 * 1024;
899 memset(&snl, 0x00, sizeof(struct sockaddr_nl));
900 snl.nl_family = AF_NETLINK;
901 snl.nl_pid = getpid();
904 uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
905 if (uevent_netlink_sock == -1) {
906 err("error getting socket: %s\n", strerror(errno));
910 /* set receive buffersize */
911 setsockopt(uevent_netlink_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
913 retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
915 err("bind failed: %s\n", strerror(errno));
916 close(uevent_netlink_sock);
917 uevent_netlink_sock = -1;
923 static void export_initial_seqnum(void)
925 char filename[PATH_SIZE];
930 strlcpy(filename, sysfs_path, sizeof(filename));
931 strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
932 fd = open(filename, O_RDONLY);
934 len = read(fd, seqnum, sizeof(seqnum)-1);
938 strcpy(seqnum, "0\n");
941 strlcpy(filename, udev_root, sizeof(filename));
942 strlcat(filename, "/" EVENT_SEQNUM, sizeof(filename));
943 create_path(filename);
944 fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
946 write(fd, seqnum, len);
951 int main(int argc, char *argv[], char *envp[])
955 struct sigaction act;
960 static const struct option options[] = {
961 { "daemon", 0, NULL, 'd' },
962 { "debug-trace", 0, NULL, 't' },
963 { "debug", 0, NULL, 'D' },
964 { "help", 0, NULL, 'h' },
965 { "version", 0, NULL, 'V' },
971 logging_init("udevd");
974 dbg("version %s\n", UDEV_VERSION);
977 option = getopt_long(argc, argv, "dDthV", options, NULL);
990 if (udev_log_priority < LOG_INFO)
991 udev_log_priority = LOG_INFO;
994 printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] [--version]\n");
997 printf("%s\n", UDEV_VERSION);
1004 if (getuid() != 0) {
1005 fprintf(stderr, "root privileges required\n");
1006 err("root privileges required\n");
1010 /* make sure std{in,out,err} fd's are in a sane state */
1011 fd = open("/dev/null", O_RDWR);
1013 fprintf(stderr, "cannot open /dev/null\n");
1014 err("cannot open /dev/null\n");
1016 if (fd > STDIN_FILENO)
1017 dup2(fd, STDIN_FILENO);
1018 if (write(STDOUT_FILENO, 0, 0) < 0)
1019 dup2(fd, STDOUT_FILENO);
1020 if (write(STDERR_FILENO, 0, 0) < 0)
1021 dup2(fd, STDERR_FILENO);
1023 /* init sockets to receive events */
1024 if (init_udevd_socket() < 0) {
1025 if (errno == EADDRINUSE) {
1026 fprintf(stderr, "another udev daemon already running\n");
1027 err("another udev daemon already running\n");
1030 fprintf(stderr, "error initializing udevd socket\n");
1031 err("error initializing udevd socket\n");
1037 if (init_uevent_netlink_sock() < 0) {
1038 fprintf(stderr, "error initializing netlink socket\n");
1039 err("error initializing netlink socket\n");
1044 /* setup signal handler pipe */
1045 retval = pipe(signal_pipe);
1047 err("error getting pipes: %s\n", strerror(errno));
1051 retval = fcntl(signal_pipe[READ_END], F_GETFL, 0);
1053 err("error fcntl on read pipe: %s\n", strerror(errno));
1056 retval = fcntl(signal_pipe[READ_END], F_SETFL, retval | O_NONBLOCK);
1058 err("error fcntl on read pipe: %s\n", strerror(errno));
1062 retval = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
1064 err("error fcntl on write pipe: %s\n", strerror(errno));
1067 retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
1069 err("error fcntl on write pipe: %s\n", strerror(errno));
1073 /* parse the rules and keep them in memory */
1075 udev_rules_init(&rules, 1);
1077 export_initial_seqnum();
1085 dbg("daemonized fork running\n");
1088 err("fork of daemon failed: %s\n", strerror(errno));
1092 dbg("child [%u] running, parent exits\n", pid);
1098 /* redirect std{out,err} fd's */
1100 dup2(fd, STDOUT_FILENO);
1101 dup2(fd, STDERR_FILENO);
1102 if (fd > STDERR_FILENO)
1105 /* set scheduling priority for the daemon */
1106 setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
1111 /* become session leader */
1113 dbg("our session is %d\n", sid);
1115 /* OOM_DISABLE == -17 */
1116 fd = open("/proc/self/oom_adj", O_RDWR);
1118 err("error disabling OOM: %s\n", strerror(errno));
1120 write(fd, "-17", 3);
1124 fd = open("/dev/kmsg", O_WRONLY);
1126 const char *str = "<6>udevd version " UDEV_VERSION " started\n";
1128 write(fd, str, strlen(str));
1132 /* set signal handlers */
1133 memset(&act, 0x00, sizeof(struct sigaction));
1134 act.sa_handler = (void (*)(int)) sig_handler;
1135 sigemptyset(&act.sa_mask);
1136 act.sa_flags = SA_RESTART;
1137 sigaction(SIGINT, &act, NULL);
1138 sigaction(SIGTERM, &act, NULL);
1139 sigaction(SIGCHLD, &act, NULL);
1140 sigaction(SIGHUP, &act, NULL);
1142 /* watch rules directory */
1143 inotify_fd = inotify_init();
1144 if (inotify_fd >= 0) {
1145 char filename[PATH_MAX];
1147 inotify_add_watch(inotify_fd, udev_rules_dir, IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1149 /* watch dynamic rules directory */
1150 strlcpy(filename, udev_root, sizeof(filename));
1151 strlcat(filename, "/"RULES_DYN_DIR, sizeof(filename));
1152 inotify_add_watch(inotify_fd, filename, IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
1153 } else if (errno == ENOSYS)
1154 err("the kernel does not support inotify, udevd can't monitor rules file changes\n");
1156 err("inotify_init failed: %s\n", strerror(errno));
1158 /* maximum limit of forked childs */
1159 value = getenv("UDEVD_MAX_CHILDS");
1161 max_childs = strtoul(value, NULL, 10);
1163 int memsize = mem_size_mb();
1165 max_childs = 128 + (memsize / 4);
1167 max_childs = UDEVD_MAX_CHILDS;
1169 info("initialize max_childs to %u\n", max_childs);
1171 /* start to throttle forking if maximum number of _running_ childs is reached */
1172 value = getenv("UDEVD_MAX_CHILDS_RUNNING");
1174 max_childs_running = strtoull(value, NULL, 10);
1176 int cpus = cpu_count();
1178 max_childs_running = 8 + (8 * cpus);
1180 max_childs_running = UDEVD_MAX_CHILDS_RUNNING;
1182 info("initialize max_childs_running to %u\n", max_childs_running);
1184 /* clear environment for forked event processes */
1187 /* export log_priority , as called programs may want to follow that setting */
1188 sprintf(udev_log, "UDEV_LOG=%i", udev_log_priority);
1194 maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
1195 maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
1196 maxfd = UDEV_MAX(maxfd, inotify_fd);
1198 while (!udev_exit) {
1199 struct udevd_uevent_msg *msg;
1203 FD_SET(signal_pipe[READ_END], &readfds);
1204 FD_SET(udevd_sock, &readfds);
1205 FD_SET(uevent_netlink_sock, &readfds);
1206 if (inotify_fd >= 0)
1207 FD_SET(inotify_fd, &readfds);
1209 fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
1212 err("error in select: %s\n", strerror(errno));
1216 /* get control message */
1217 if (FD_ISSET(udevd_sock, &readfds))
1220 /* get netlink message */
1221 if (FD_ISSET(uevent_netlink_sock, &readfds)) {
1222 msg = get_netlink_msg();
1224 msg_queue_insert(msg);
1227 /* received a signal, clear our notification pipe */
1228 if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
1231 read(signal_pipe[READ_END], &buf, sizeof(buf));
1234 /* rules directory inotify watch */
1235 if ((inotify_fd >= 0) && FD_ISSET(inotify_fd, &readfds)) {
1238 /* discard all possible events, we can just reload the config */
1239 if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes > 0) {
1243 buf = malloc(nbytes);
1245 err("error getting buffer for inotify, disable watching\n");
1249 read(inotify_fd, buf, nbytes);
1254 /* rules changed, set by inotify or a HUP signal */
1255 if (reload_config) {
1257 udev_rules_cleanup(&rules);
1258 udev_rules_init(&rules, 1);
1261 /* forked child has returned */
1262 if (sigchilds_waiting) {
1263 sigchilds_waiting = 0;
1270 msg_queue_manager();
1276 udev_rules_cleanup(&rules);
1280 if (signal_pipe[READ_END] >= 0)
1281 close(signal_pipe[READ_END]);
1282 if (signal_pipe[WRITE_END] >= 0)
1283 close(signal_pipe[WRITE_END]);
1285 if (udevd_sock >= 0)
1287 if (inotify_fd >= 0)
1289 if (uevent_netlink_sock >= 0)
1290 close(uevent_netlink_sock);