/* * Copyright (C) 2004-2008 Kay Sievers * Copyright (C) 2004 Chris Friesen * Copyright (C) 2009 Canonical Ltd. * Copyright (C) 2009 Scott James Remnant * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef HAVE_INOTIFY #include #endif #include "udev.h" #define UDEVD_PRIORITY -4 #define UDEV_PRIORITY -2 /* maximum limit of forked childs */ #define UDEVD_MAX_CHILDS 256 static int debug; static void log_fn(struct udev *udev, int priority, const char *file, int line, const char *fn, const char *format, va_list args) { if (debug) { fprintf(stderr, "[%d] %s: ", (int) getpid(), fn); vfprintf(stderr, format, args); } else { vsyslog(priority, format, args); } } static void reap_sigchilds(void); static int debug_trace; static struct udev_rules *rules; static struct udev_ctrl *udev_ctrl; static struct udev_monitor *kernel_monitor; static volatile sig_atomic_t sigchilds_waiting; static volatile sig_atomic_t udev_exit; static volatile sig_atomic_t reload_config; static volatile sig_atomic_t signal_received; static volatile pid_t settle_pid; static int run_exec_q; static int stop_exec_q; static int max_childs; static int childs; static struct udev_list_node event_list; enum event_state { EVENT_QUEUED, EVENT_FINISHED, EVENT_FAILED, }; static struct udev_event *node_to_event(struct udev_list_node *node) { char *event; event = (char *)node; event -= offsetof(struct udev_event, node); return (struct udev_event *)event; } static void export_event_state(struct udev_event *event, enum event_state state) { char filename[UTIL_PATH_SIZE]; char filename_failed[UTIL_PATH_SIZE]; char *s; size_t l; /* location of queue file */ snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu", udev_get_dev_path(event->udev), udev_device_get_seqnum(event->dev)); /* location of failed file */ s = filename_failed; l = util_strpcpyl(&s, sizeof(filename_failed), udev_get_dev_path(event->udev), "/.udev/failed/", NULL); util_path_encode(udev_device_get_devpath(event->dev), s, l); switch (state) { case EVENT_QUEUED: if(unlink(filename_failed) == 0) util_delete_path(event->udev, filename_failed); util_create_path(event->udev, filename); udev_selinux_setfscreatecon(event->udev, filename, S_IFLNK); symlink(udev_device_get_devpath(event->dev), filename); udev_selinux_resetfscreatecon(event->udev); break; case EVENT_FINISHED: if (udev_device_get_devpath_old(event->dev) != NULL) { /* "move" event - rename failed file to current name, do not delete failed */ char filename_failed_old[UTIL_PATH_SIZE]; s = filename_failed_old; l = util_strpcpyl(&s, sizeof(filename_failed_old), udev_get_dev_path(event->udev), "/.udev/failed/", NULL); util_path_encode(udev_device_get_devpath_old(event->dev), s, l); if (rename(filename_failed_old, filename_failed) == 0) info(event->udev, "renamed devpath, moved failed state of '%s' to %s'\n", udev_device_get_devpath_old(event->dev), udev_device_get_devpath(event->dev)); } else { if (unlink(filename_failed) == 0) util_delete_path(event->udev, filename_failed); } unlink(filename); /* clean up possibly empty queue directory */ if (udev_list_is_empty(&event_list)) util_delete_path(event->udev, filename); break; case EVENT_FAILED: /* move failed event to the failed directory */ util_create_path(event->udev, filename_failed); rename(filename, filename_failed); /* clean up possibly empty queue directory */ if (udev_list_is_empty(&event_list)) util_delete_path(event->udev, filename); break; } return; } static void event_queue_delete(struct udev_event *event) { udev_list_node_remove(&event->node); /* mark as failed, if "add" event returns non-zero */ if (event->exitstatus && strcmp(udev_device_get_action(event->dev), "add") == 0) export_event_state(event, EVENT_FAILED); else export_event_state(event, EVENT_FINISHED); udev_device_unref(event->dev); udev_event_unref(event); } static void event_sig_handler(int signum) { if (signum == SIGALRM) _exit(1); } static void event_fork(struct udev_event *event) { pid_t pid; struct sigaction act; int err; #if 0 /* single process, no forking, just for testing/profiling */ err = udev_event_execute_rules(event, rules); if (err == 0 && !event->ignore_device && udev_get_run(event->udev)) udev_event_execute_run(event); info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err); event_queue_delete(event); return; #endif if (debug_trace) { event->trace = 1; fprintf(stderr, "fork %s (%llu)\n", udev_device_get_syspath(event->dev), udev_device_get_seqnum(event->dev)); } pid = fork(); switch (pid) { case 0: /* child */ udev_ctrl_unref(udev_ctrl); logging_close(); logging_init("udevd-event"); setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY); /* set signal handlers */ memset(&act, 0x00, sizeof(act)); act.sa_handler = event_sig_handler; sigemptyset (&act.sa_mask); act.sa_flags = 0; sigaction(SIGALRM, &act, NULL); /* reset to default */ act.sa_handler = SIG_DFL; sigaction(SIGINT, &act, NULL); sigaction(SIGTERM, &act, NULL); sigaction(SIGCHLD, &act, NULL); sigaction(SIGHUP, &act, NULL); /* set timeout to prevent hanging processes */ alarm(UDEV_EVENT_TIMEOUT); /* apply rules, create node, symlinks */ err = udev_event_execute_rules(event, rules); /* rules may change/disable the timeout */ if (udev_device_get_event_timeout(event->dev) >= 0) alarm(udev_device_get_event_timeout(event->dev)); /* execute RUN= */ if (err == 0 && !event->ignore_device && udev_get_run(event->udev)) udev_event_execute_run(event); /* apply/restore inotify watch */ if (err == 0 && event->inotify_watch) { udev_watch_begin(event->udev, event->dev); udev_device_update_db(event->dev); } /* send processed event back to the kernel netlink socket */ udev_monitor_send_device(kernel_monitor, event->dev); info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err); logging_close(); if (err != 0) exit(1); exit(0); case -1: err(event->udev, "fork of child failed: %m\n"); event_queue_delete(event); break; default: /* get SIGCHLD in main loop */ info(event->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n", udev_device_get_seqnum(event->dev), pid, udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev), time(NULL) - event->queue_time); event->pid = pid; childs++; } } static void event_queue_insert(struct udev_event *event) { char filename[UTIL_PATH_SIZE]; int fd; event->queue_time = time(NULL); export_event_state(event, EVENT_QUEUED); info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(event->dev), udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev)); util_strscpyl(filename, sizeof(filename), udev_get_dev_path(event->udev), "/.udev/uevent_seqnum", NULL); fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644); if (fd >= 0) { char str[32]; int len; len = sprintf(str, "%llu\n", udev_device_get_seqnum(event->dev)); write(fd, str, len); close(fd); } udev_list_node_append(&event->node, &event_list); run_exec_q = 1; /* run all events with a timeout set immediately */ if (udev_device_get_timeout(event->dev) > 0) { event_fork(event); return; } } static int mem_size_mb(void) { FILE *f; char buf[4096]; long int memsize = -1; f = fopen("/proc/meminfo", "r"); if (f == NULL) return -1; while (fgets(buf, sizeof(buf), f) != NULL) { long int value; if (sscanf(buf, "MemTotal: %ld kB", &value) == 1) { memsize = value / 1024; break; } } fclose(f); return memsize; } static int compare_devpath(const char *running, const char *waiting) { int i = 0; while (running[i] != '\0' && running[i] == waiting[i]) i++; /* identical device event found */ if (running[i] == '\0' && waiting[i] == '\0') return 1; /* parent device event found */ if (running[i] == '\0' && waiting[i] == '/') return 2; /* child device event found */ if (running[i] == '/' && waiting[i] == '\0') return 3; /* no matching event */ return 0; } /* lookup event for identical, parent, child device */ static int devpath_busy(struct udev_event *event) { struct udev_list_node *loop; if (event->delaying_seqnum > 0) { } /* check if queue contains events we depend on */ udev_list_node_foreach(loop, &event_list) { struct udev_event *loop_event = node_to_event(loop); /* we already found a later event, earlier can not block us, no need to check again */ if (udev_device_get_seqnum(loop_event->dev) < event->delaying_seqnum) continue; /* event we checked earlier still exists, no need to check again */ if (udev_device_get_seqnum(loop_event->dev) == event->delaying_seqnum) return 2; /* found ourself, no later event can block us */ if (udev_device_get_seqnum(loop_event->dev) >= udev_device_get_seqnum(event->dev)) break; /* check our old name */ if (udev_device_get_devpath_old(event->dev) != NULL) if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0) { event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); return 3; } /* check identical, parent, or child device event */ if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) { dbg(event->udev, "%llu, device event still pending %llu (%s)\n", udev_device_get_seqnum(event->dev), udev_device_get_seqnum(loop_event->dev), udev_device_get_devpath(loop_event->dev)); event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); return 4; } /* check for our major:minor number */ if (major(udev_device_get_devnum(event->dev)) > 0 && udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) && strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) { dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n", udev_device_get_seqnum(event->dev), udev_device_get_seqnum(loop_event->dev), major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev))); event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); return 5; } } return 0; } /* serializes events for the identical and parent and child devices */ static void event_queue_manager(struct udev *udev) { struct udev_list_node *loop; struct udev_list_node *tmp; start_over: if (udev_list_is_empty(&event_list)) { if (childs > 0) { err(udev, "event list empty, but childs count is %i", childs); childs = 0; } return; } udev_list_node_foreach_safe(loop, tmp, &event_list) { struct udev_event *loop_event = node_to_event(loop); if (childs >= max_childs) { info(udev, "maximum number (%i) of childs reached\n", childs); break; } if (loop_event->pid != 0) continue; /* do not start event if parent or child event is still running */ if (devpath_busy(loop_event) != 0) { dbg(udev, "delay seq %llu (%s)\n", udev_device_get_seqnum(loop_event->dev), udev_device_get_devpath(loop_event->dev)); continue; } event_fork(loop_event); dbg(udev, "moved seq %llu to running list\n", udev_device_get_seqnum(loop_event->dev)); /* retry if events finished in the meantime */ if (sigchilds_waiting) { sigchilds_waiting = 0; reap_sigchilds(); goto start_over; } } } /* receive the udevd message from userspace */ static void handle_ctrl_msg(struct udev_ctrl *uctrl) { struct udev *udev = udev_ctrl_get_udev(uctrl); struct udev_ctrl_msg *ctrl_msg; const char *str; int i; ctrl_msg = udev_ctrl_receive_msg(uctrl); if (ctrl_msg == NULL) return; i = udev_ctrl_get_set_log_level(ctrl_msg); if (i >= 0) { info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i); udev_set_log_priority(udev, i); } if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) { info(udev, "udevd message (STOP_EXEC_QUEUE) received\n"); stop_exec_q = 1; } if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) { info(udev, "udevd message (START_EXEC_QUEUE) received\n"); stop_exec_q = 0; event_queue_manager(udev); } if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) { info(udev, "udevd message (RELOAD_RULES) received\n"); reload_config = 1; } str = udev_ctrl_get_set_env(ctrl_msg); if (str != NULL) { char *key; key = strdup(str); if (key != NULL) { char *val; val = strchr(key, '='); if (val != NULL) { val[0] = '\0'; val = &val[1]; if (val[0] == '\0') { info(udev, "udevd message (ENV) received, unset '%s'\n", key); udev_add_property(udev, key, NULL); } else { info(udev, "udevd message (ENV) received, set '%s=%s'\n", key, val); udev_add_property(udev, key, val); } } else { err(udev, "wrong key format '%s'\n", key); } free(key); } } i = udev_ctrl_get_set_max_childs(ctrl_msg); if (i >= 0) { info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i); max_childs = i; } settle_pid = udev_ctrl_get_settle(ctrl_msg); if (settle_pid > 0) { info(udev, "udevd message (SETTLE) received\n"); } udev_ctrl_msg_unref(ctrl_msg); } /* read inotify messages */ static int handle_inotify(struct udev *udev) { int nbytes, pos; char *buf; struct inotify_event *ev; if ((ioctl(inotify_fd, FIONREAD, &nbytes) < 0) || (nbytes <= 0)) return 0; buf = malloc(nbytes); if (buf == NULL) { err(udev, "error getting buffer for inotify, disable watching\n"); close(inotify_fd); inotify_fd = -1; return 0; } read(inotify_fd, buf, nbytes); for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) { struct udev_device *dev; ev = (struct inotify_event *)(buf + pos); if (ev->len) { dbg(udev, "inotify event: %x for %s\n", ev->mask, ev->name); reload_config = 1; continue; } dev = udev_watch_lookup(udev, ev->wd); if (dev != NULL) { dbg(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev)); if (ev->mask & IN_CLOSE_WRITE) { char filename[UTIL_PATH_SIZE]; int fd; info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev)); util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL); fd = open(filename, O_WRONLY); if (fd < 0 || write(fd, "change", 6) < 0) info(udev, "error writing uevent: %m\n"); close(fd); } if (ev->mask & IN_IGNORED) udev_watch_end(udev, dev); udev_device_unref(dev); } } free (buf); return 0; } static void sig_handler(int signum) { switch (signum) { case SIGINT: case SIGTERM: udev_exit = 1; break; case SIGCHLD: /* set flag, then write to pipe if needed */ sigchilds_waiting = 1; break; case SIGHUP: reload_config = 1; break; } signal_received = 1; } static void udev_done(int pid, int exitstatus) { struct udev_list_node *loop; /* find event associated with pid and delete it */ udev_list_node_foreach(loop, &event_list) { struct udev_event *loop_event = node_to_event(loop); if (loop_event->pid == pid) { info(loop_event->udev, "seq %llu cleanup, pid [%d], status %i, %ld seconds old\n", udev_device_get_seqnum(loop_event->dev), loop_event->pid, exitstatus, time(NULL) - loop_event->queue_time); loop_event->exitstatus = exitstatus; if (debug_trace) fprintf(stderr, "exit %s (%llu)\n", udev_device_get_syspath(loop_event->dev), udev_device_get_seqnum(loop_event->dev)); event_queue_delete(loop_event); childs--; /* there may be dependent events waiting */ run_exec_q = 1; return; } } } static void reap_sigchilds(void) { pid_t pid; int status; while (1) { pid = waitpid(-1, &status, WNOHANG); if (pid <= 0) break; if (WIFEXITED(status)) status = WEXITSTATUS(status); else if (WIFSIGNALED(status)) status = WTERMSIG(status) + 128; else status = 0; udev_done(pid, status); } } static void cleanup_queue_dir(struct udev *udev) { char dirname[UTIL_PATH_SIZE]; char filename[UTIL_PATH_SIZE]; DIR *dir; util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/uevent_seqnum", NULL); unlink(filename); util_strscpyl(dirname, sizeof(dirname), udev_get_dev_path(udev), "/.udev/queue", NULL); dir = opendir(dirname); if (dir != NULL) { while (1) { struct dirent *dent; dent = readdir(dir); if (dent == NULL || dent->d_name[0] == '\0') break; if (dent->d_name[0] == '.') continue; unlinkat(dirfd(dir), dent->d_name, 0); } closedir(dir); rmdir(dirname); } } static void export_initial_seqnum(struct udev *udev) { char filename[UTIL_PATH_SIZE]; int fd; char seqnum[32]; ssize_t len = 0; util_strscpyl(filename, sizeof(filename), udev_get_sys_path(udev), "/kernel/uevent_seqnum", NULL); fd = open(filename, O_RDONLY); if (fd >= 0) { len = read(fd, seqnum, sizeof(seqnum)-1); close(fd); } if (len <= 0) { strcpy(seqnum, "0\n"); len = 3; } util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/uevent_seqnum", NULL); util_create_path(udev, filename); fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644); if (fd >= 0) { write(fd, seqnum, len); close(fd); } } static void startup_log(struct udev *udev) { FILE *f; char path[UTIL_PATH_SIZE]; struct stat statbuf; f = fopen("/dev/kmsg", "w"); if (f != NULL) fprintf(f, "<6>udev: starting version " VERSION "\n"); util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/class/mem/null", NULL); if (lstat(path, &statbuf) == 0 && S_ISDIR(statbuf.st_mode)) { const char *depr_str = "udev: missing sysfs features; please update the kernel " "or disable the kernel's CONFIG_SYSFS_DEPRECATED option; " "udev may fail to work correctly"; if (f != NULL) fprintf(f, "<3>%s\n", depr_str); err(udev, "%s\n", depr_str); sleep(3); } if (f != NULL) fclose(f); } int main(int argc, char *argv[]) { struct udev *udev; int fd; struct sigaction act; const char *value; int daemonize = 0; int resolve_names = 1; static const struct option options[] = { { "daemon", no_argument, NULL, 'd' }, { "debug-trace", no_argument, NULL, 't' }, { "debug", no_argument, NULL, 'D' }, { "help", no_argument, NULL, 'h' }, { "version", no_argument, NULL, 'V' }, { "resolve-names", required_argument, NULL, 'N' }, {} }; int rc = 1; udev = udev_new(); if (udev == NULL) goto exit; logging_init("udevd"); udev_set_log_fn(udev, log_fn); info(udev, "version %s\n", VERSION); udev_selinux_init(udev); while (1) { int option; option = getopt_long(argc, argv, "dDthV", options, NULL); if (option == -1) break; switch (option) { case 'd': daemonize = 1; break; case 't': debug_trace = 1; break; case 'D': debug = 1; if (udev_get_log_priority(udev) < LOG_INFO) udev_set_log_priority(udev, LOG_INFO); break; case 'N': if (strcmp (optarg, "early") == 0) { resolve_names = 1; } else if (strcmp (optarg, "late") == 0) { resolve_names = 0; } else if (strcmp (optarg, "never") == 0) { resolve_names = -1; } else { fprintf(stderr, "resolve-names must be early, late or never\n"); err(udev, "resolve-names must be early, late or never\n"); goto exit; } break; case 'h': printf("Usage: udevd [--help] [--daemon] [--debug-trace] [--debug] " "[--resolve-names=early|late|never] [--version]\n"); goto exit; case 'V': printf("%s\n", VERSION); goto exit; default: goto exit; } } if (getuid() != 0) { fprintf(stderr, "root privileges required\n"); err(udev, "root privileges required\n"); goto exit; } /* make sure std{in,out,err} fd's are in a sane state */ fd = open("/dev/null", O_RDWR); if (fd < 0) { fprintf(stderr, "cannot open /dev/null\n"); err(udev, "cannot open /dev/null\n"); } if (write(STDOUT_FILENO, 0, 0) < 0) dup2(fd, STDOUT_FILENO); if (write(STDERR_FILENO, 0, 0) < 0) dup2(fd, STDERR_FILENO); /* init control socket, bind() ensures, that only one udevd instance is running */ udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH); if (udev_ctrl == NULL) { fprintf(stderr, "error initializing control socket"); err(udev, "error initializing udevd socket"); rc = 1; goto exit; } if (udev_ctrl_enable_receiving(udev_ctrl) < 0) { fprintf(stderr, "error binding control socket, seems udevd is already running\n"); err(udev, "error binding control socket, seems udevd is already running\n"); rc = 1; goto exit; } kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel"); if (kernel_monitor == NULL || udev_monitor_enable_receiving(kernel_monitor) < 0) { fprintf(stderr, "error initializing netlink socket\n"); err(udev, "error initializing netlink socket\n"); rc = 3; goto exit; } udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024); rules = udev_rules_new(udev, resolve_names); if (rules == NULL) { err(udev, "error reading rules\n"); goto exit; } udev_list_init(&event_list); cleanup_queue_dir(udev); export_initial_seqnum(udev); if (daemonize) { pid_t pid; pid = fork(); switch (pid) { case 0: dbg(udev, "daemonized fork running\n"); break; case -1: err(udev, "fork of daemon failed: %m\n"); rc = 4; goto exit; default: dbg(udev, "child [%u] running, parent exits\n", pid); rc = 0; goto exit; } } /* redirect std{out,err} */ if (!debug && !debug_trace) { dup2(fd, STDIN_FILENO); dup2(fd, STDOUT_FILENO); dup2(fd, STDERR_FILENO); } if (fd > STDERR_FILENO) close(fd); /* set scheduling priority for the daemon */ setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY); chdir("/"); umask(022); setsid(); /* OOM_DISABLE == -17 */ fd = open("/proc/self/oom_adj", O_RDWR); if (fd < 0) err(udev, "error disabling OOM: %m\n"); else { write(fd, "-17", 3); close(fd); } startup_log(udev); /* set signal handlers */ memset(&act, 0x00, sizeof(struct sigaction)); act.sa_handler = sig_handler; sigemptyset(&act.sa_mask); act.sa_flags = SA_RESTART; sigaction(SIGINT, &act, NULL); sigaction(SIGTERM, &act, NULL); sigaction(SIGCHLD, &act, NULL); sigaction(SIGHUP, &act, NULL); /* watch rules directory */ udev_watch_init(udev); if (inotify_fd >= 0) { if (udev_get_rules_path(udev) != NULL) { inotify_add_watch(inotify_fd, udev_get_rules_path(udev), IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); } else { char filename[UTIL_PATH_SIZE]; inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d", IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d", IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); /* watch dynamic rules directory */ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/rules.d", NULL); inotify_add_watch(inotify_fd, filename, IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); } udev_watch_restore(udev); } /* in trace mode run one event after the other */ if (debug_trace) { max_childs = 1; } else { int memsize = mem_size_mb(); if (memsize > 0) max_childs = 128 + (memsize / 4); else max_childs = UDEVD_MAX_CHILDS; } /* possibly overwrite maximum limit of executed events */ value = getenv("UDEVD_MAX_CHILDS"); if (value) max_childs = strtoul(value, NULL, 10); info(udev, "initialize max_childs to %u\n", max_childs); while (!udev_exit) { sigset_t blocked_mask, orig_mask; struct pollfd pfd[4]; struct pollfd *ctrl_poll, *monitor_poll, *inotify_poll = NULL; int nfds = 0; int fdcount; sigfillset(&blocked_mask); sigprocmask(SIG_SETMASK, &blocked_mask, &orig_mask); if (signal_received) { sigprocmask(SIG_SETMASK, &orig_mask, NULL); goto handle_signals; } ctrl_poll = &pfd[nfds++]; ctrl_poll->fd = udev_ctrl_get_fd(udev_ctrl); ctrl_poll->events = POLLIN; monitor_poll = &pfd[nfds++]; monitor_poll->fd = udev_monitor_get_fd(kernel_monitor); monitor_poll->events = POLLIN; if (inotify_fd >= 0) { inotify_poll = &pfd[nfds++]; inotify_poll->fd = inotify_fd; inotify_poll->events = POLLIN; } fdcount = ppoll(pfd, nfds, NULL, &orig_mask); sigprocmask(SIG_SETMASK, &orig_mask, NULL); if (fdcount < 0) { if (errno == EINTR) goto handle_signals; err(udev, "error in select: %m\n"); continue; } /* get control message */ if (ctrl_poll->revents & POLLIN) handle_ctrl_msg(udev_ctrl); /* get kernel uevent */ if (monitor_poll->revents & POLLIN) { struct udev_device *dev; dev = udev_monitor_receive_device(kernel_monitor); if (dev != NULL) { struct udev_event *event; event = udev_event_new(dev); if (event != NULL) event_queue_insert(event); else udev_device_unref(dev); } } /* rules directory inotify watch */ if (inotify_poll && (inotify_poll->revents & POLLIN)) handle_inotify(udev); handle_signals: signal_received = 0; /* rules changed, set by inotify or a HUP signal */ if (reload_config) { struct udev_rules *rules_new; reload_config = 0; rules_new = udev_rules_new(udev, resolve_names); if (rules_new != NULL) { udev_rules_unref(rules); rules = rules_new; } } if (sigchilds_waiting) { sigchilds_waiting = 0; reap_sigchilds(); } if (run_exec_q) { run_exec_q = 0; if (!stop_exec_q) event_queue_manager(udev); } if (settle_pid > 0) { kill(settle_pid, SIGUSR1); settle_pid = 0; } } cleanup_queue_dir(udev); rc = 0; exit: udev_rules_unref(rules); udev_ctrl_unref(udev_ctrl); if (inotify_fd >= 0) close(inotify_fd); udev_monitor_unref(kernel_monitor); udev_selinux_exit(udev); udev_unref(udev); logging_close(); return rc; }