/*
- * udevd.c - hotplug event serializer
+ * udevd.c - event listener and serializer
*
- * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
* Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
*
*
*/
#include <stddef.h>
-#include <sys/wait.h>
#include <signal.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <sys/time.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <syslog.h>
+#include <time.h>
+#include <sys/select.h>
+#include <sys/wait.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
-#include <fcntl.h>
-#include "klibc_fixups.h"
-#include <sys/sysinfo.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <linux/types.h>
+#include <linux/netlink.h>
-#include "list.h"
#include "udev.h"
-#include "udev_lib.h"
-#include "udev_version.h"
+#include "udev_rules.h"
#include "udevd.h"
-#include "logging.h"
-static int pipefds[2];
-static unsigned long long expected_seqnum = 0;
-static volatile int children_waiting;
-static volatile int run_msg_q;
-static volatile int sig_flag;
+static struct udev_rules rules;
+static int udevd_sock;
+static int uevent_netlink_sock;
+static int inotify_fd;
+static pid_t sid;
+
+static int signal_pipe[2] = {-1, -1};
+static volatile int sigchilds_waiting;
+static volatile int udev_exit;
+static volatile int reload_config;
static int run_exec_q;
+static int stop_exec_q;
+static int max_childs;
+static int max_childs_running;
+static char udev_log[32];
-static LIST_HEAD(msg_list);
static LIST_HEAD(exec_list);
static LIST_HEAD(running_list);
-static void exec_queue_manager(void);
-static void msg_queue_manager(void);
-static void user_sighandler(void);
-static void reap_kids(void);
-char *udev_bin;
-#ifdef LOG
-unsigned char logname[LOGNAME_SIZE];
-void log_message (int level, const char *format, ...)
+#ifdef USE_LOG
+void log_message(int priority, const char *format, ...)
{
- va_list args;
+ va_list args;
+
+ if (priority > udev_log_priority)
+ return;
va_start(args, format);
- vsyslog(level, format, args);
+ vsyslog(priority, format, args);
va_end(args);
}
#endif
-#define msg_dump(msg) \
- dbg("msg_dump: sequence %llu, '%s', '%s', '%s'", \
- msg->seqnum, msg->action, msg->devpath, msg->subsystem);
-
-static void msg_dump_queue(void)
+static void asmlinkage udev_event_sig_handler(int signum)
{
-#ifdef DEBUG
- struct hotplug_msg *msg;
-
- list_for_each_entry(msg, &msg_list, list)
- dbg("sequence %llu in queue", msg->seqnum);
-#endif
+ if (signum == SIGALRM)
+ exit(1);
}
-static struct hotplug_msg *msg_create(void)
+static int udev_event_process(struct uevent_msg *msg)
{
- struct hotplug_msg *new_msg;
+ struct sigaction act;
+ struct udevice *udev;
+ int i;
+ int retval;
- new_msg = malloc(sizeof(struct hotplug_msg));
- if (new_msg == NULL)
- dbg("error malloc");
- return new_msg;
-}
+ /* set signal handlers */
+ memset(&act, 0x00, sizeof(act));
+ act.sa_handler = (void (*)(int)) udev_event_sig_handler;
+ sigemptyset (&act.sa_mask);
+ act.sa_flags = 0;
+ sigaction(SIGALRM, &act, NULL);
-static void run_queue_delete(struct hotplug_msg *msg)
-{
- list_del(&msg->list);
- free(msg);
+ /* reset to default */
+ act.sa_handler = SIG_DFL;
+ sigaction(SIGINT, &act, NULL);
+ sigaction(SIGTERM, &act, NULL);
+ sigaction(SIGCHLD, &act, NULL);
+ sigaction(SIGHUP, &act, NULL);
+
+ /* trigger timeout to prevent hanging processes */
+ alarm(UDEV_ALARM_TIMEOUT);
+
+ /* reconstruct event environment from message */
+ for (i = 0; msg->envp[i]; i++)
+ putenv(msg->envp[i]);
+
+ udev = udev_device_init();
+ if (udev == NULL)
+ return -1;
+ strlcpy(udev->action, msg->action, sizeof(udev->action));
+ sysfs_device_set_values(udev->dev, msg->devpath, msg->subsystem);
+ udev->devt = msg->devt;
+
+ retval = udev_device_event(&rules, udev);
+
+ /* run programs collected by RUN-key*/
+ if (retval == 0 && !udev->ignore_device && udev_run) {
+ struct name_entry *name_loop;
+
+ dbg("executing run list");
+ list_for_each_entry(name_loop, &udev->run_list, node) {
+ if (strncmp(name_loop->name, "socket:", strlen("socket:")) == 0)
+ pass_env_to_socket(&name_loop->name[strlen("socket:")], msg->devpath, msg->action);
+ else {
+ char program[PATH_SIZE];
+
+ strlcpy(program, name_loop->name, sizeof(program));
+ udev_rules_apply_format(udev, program, sizeof(program));
+ if (run_program(program, udev->dev->subsystem, NULL, 0, NULL,
+ (udev_log_priority >= LOG_INFO)))
+ retval = -1;
+ }
+ }
+ }
+
+ udev_device_cleanup(udev);
+ return retval;
}
-/* orders the message in the queue by sequence number */
-static void msg_queue_insert(struct hotplug_msg *msg)
+enum event_state {
+ EVENT_QUEUED,
+ EVENT_FINISHED,
+ EVENT_FAILED,
+};
+
+static void export_event_state(struct uevent_msg *msg, enum event_state state)
{
- struct hotplug_msg *loop_msg;
- struct sysinfo info;
-
- /* sort message by sequence number into list. events
- * will tend to come in order, so scan the list backwards
- */
- list_for_each_entry_reverse(loop_msg, &msg_list, list)
- if (loop_msg->seqnum < msg->seqnum)
- break;
+ char filename[PATH_SIZE];
+ char filename_failed[PATH_SIZE];
+ char target[PATH_SIZE];
+ size_t start, end, i;
+ struct uevent_msg *loop_msg;
+
+ /* add location of queue files */
+ strlcpy(filename, udev_root, sizeof(filename));
+ strlcat(filename, "/", sizeof(filename));
+ start = strlcat(filename, EVENT_QUEUE_DIR, sizeof(filename));
+ end = strlcat(filename, msg->devpath, sizeof(filename));
+ if (end > sizeof(filename))
+ end = sizeof(filename);
+
+ /* replace '/' to transform path into a filename */
+ for (i = start+1; i < end; i++)
+ if (filename[i] == '/')
+ filename[i] = PATH_TO_NAME_CHAR;
+
+ /* add location of failed files */
+ strlcpy(filename_failed, udev_root, sizeof(filename_failed));
+ strlcat(filename_failed, "/", sizeof(filename_failed));
+ start = strlcat(filename_failed, EVENT_FAILED_DIR, sizeof(filename_failed));
+ end = strlcat(filename_failed, msg->devpath, sizeof(filename_failed));
+ if (end > sizeof(filename_failed))
+ end = sizeof(filename_failed);
+
+ /* replace '/' to transform path into a filename */
+ for (i = start+1; i < end; i++)
+ if (filename_failed[i] == '/')
+ filename_failed[i] = PATH_TO_NAME_CHAR;
+
+ switch (state) {
+ case EVENT_QUEUED:
+ unlink(filename_failed);
+ delete_path(filename_failed);
+
+ strlcpy(target, sysfs_path, sizeof(target));
+ strlcat(target, msg->devpath, sizeof(target));
+ create_path(filename);
+ symlink(target, filename);
+ return;
+ case EVENT_FINISHED:
+ case EVENT_FAILED:
+ unlink(filename_failed);
+ delete_path(filename_failed);
+
+ /* don't remove, if events for the same path are still pending */
+ list_for_each_entry(loop_msg, &running_list, node)
+ if (loop_msg->devpath && strcmp(loop_msg->devpath, msg->devpath) == 0)
+ return;
+
+ list_for_each_entry(loop_msg, &exec_list, node)
+ if (loop_msg->devpath && strcmp(loop_msg->devpath, msg->devpath) == 0)
+ return;
+
+ /* move failed events to the failed directory */
+ if (state == EVENT_FAILED) {
+ create_path(filename_failed);
+ rename(filename, filename_failed);
+ } else {
+ unlink(filename);
+ }
- /* store timestamp of queuing */
- sysinfo(&info);
- msg->queue_time = info.uptime;
+ /* clean up the queue directory */
+ delete_path(filename);
+
+ return;
+ }
+}
- list_add(&msg->list, &loop_msg->list);
- dbg("queued message seq %llu", msg->seqnum);
+static void msg_queue_delete(struct uevent_msg *msg)
+{
+ list_del(&msg->node);
- /* run msg queue manager */
- run_msg_q = 1;
+ /* mark as failed, if add event returns non-zero */
+ if (msg->exitstatus && strcmp(msg->action, "add") == 0)
+ export_event_state(msg, EVENT_FAILED);
+ else
+ export_event_state(msg, EVENT_FINISHED);
- return ;
+ free(msg);
}
-/* forks event and removes event from run queue when finished */
-static void udev_run(struct hotplug_msg *msg)
+static void udev_event_run(struct uevent_msg *msg)
{
pid_t pid;
- char action[ACTION_SIZE];
- char devpath[DEVPATH_SIZE];
- char seqnum[SEQNUM_SIZE];
- char *env[] = { action, devpath, seqnum, NULL };
-
- snprintf(action, ACTION_SIZE-1, "ACTION=%s", msg->action);
- action[ACTION_SIZE-1] = '\0';
- snprintf(devpath, DEVPATH_SIZE-1, "DEVPATH=%s", msg->devpath);
- devpath[DEVPATH_SIZE-1] = '\0';
- sprintf(seqnum, "SEQNUM=%llu", msg->seqnum);
+ int retval;
pid = fork();
switch (pid) {
case 0:
/* child */
- execle(udev_bin, "udev", msg->subsystem, NULL, env);
- dbg("exec of child failed");
- exit(1);
- break;
+ close(uevent_netlink_sock);
+ close(udevd_sock);
+ if (inotify_fd > 0)
+ close(inotify_fd);
+ close(signal_pipe[READ_END]);
+ close(signal_pipe[WRITE_END]);
+ logging_close();
+
+ logging_init("udevd-event");
+ setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
+ retval = udev_event_process(msg);
+ info("seq %llu finished", msg->seqnum);
+
+ logging_close();
+ if (retval)
+ exit(1);
+ exit(0);
case -1:
- dbg("fork of child failed");
- run_queue_delete(msg);
- /* note: we never managed to run, so we had no impact on
- * running_with_devpath(), so don't bother setting run_exec_q
- */
+ err("fork of child failed: %s", strerror(errno));
+ msg_queue_delete(msg);
break;
default:
/* get SIGCHLD in main loop */
- dbg("==> exec seq %llu [%d] working at '%s'", msg->seqnum, pid, msg->devpath);
+ info("seq %llu forked, pid [%d], '%s' '%s', %ld seconds old",
+ msg->seqnum, pid, msg->action, msg->subsystem, time(NULL) - msg->queue_time);
msg->pid = pid;
}
}
-/* returns already running task with devpath */
-static struct hotplug_msg *running_with_devpath(struct hotplug_msg *msg)
+static void msg_queue_insert(struct uevent_msg *msg)
{
- struct hotplug_msg *loop_msg;
- list_for_each_entry(loop_msg, &running_list, list)
- if (strncmp(loop_msg->devpath, msg->devpath, sizeof(loop_msg->devpath)) == 0)
- return loop_msg;
- return NULL;
+ msg->queue_time = time(NULL);
+
+ export_event_state(msg, EVENT_QUEUED);
+
+ /* run all events with a timeout set immediately */
+ if (msg->timeout != 0) {
+ list_add_tail(&msg->node, &running_list);
+ udev_event_run(msg);
+ return;
+ }
+
+ list_add_tail(&msg->node, &exec_list);
+ run_exec_q = 1;
}
-/* exec queue management routine executes the events and delays events for the same devpath */
-static void exec_queue_manager()
+/* runs event and removes event from run queue when finished */
+static int running_processes(void)
{
- struct hotplug_msg *loop_msg;
- struct hotplug_msg *tmp_msg;
- struct hotplug_msg *msg;
-
- list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, list) {
- msg = running_with_devpath(loop_msg);
- if (!msg) {
- /* move event to run list */
- list_move_tail(&loop_msg->list, &running_list);
- udev_run(loop_msg);
- dbg("moved seq %llu to running list", loop_msg->seqnum);
- } else {
- dbg("delay seq %llu, cause seq %llu already working on '%s'",
- loop_msg->seqnum, msg->seqnum, msg->devpath);
- }
+ int f;
+ static char buf[4096];
+ int len;
+ int running;
+ const char *pos;
+
+ f = open("/proc/stat", O_RDONLY);
+ if (f == -1)
+ return -1;
+
+ len = read(f, buf, sizeof(buf)-1);
+ close(f);
+
+ if (len <= 0)
+ return -1;
+ else
+ buf[len] = '\0';
+
+ pos = strstr(buf, "procs_running ");
+ if (pos == NULL)
+ return -1;
+
+ if (sscanf(pos, "procs_running %u", &running) != 1)
+ return -1;
+
+ return running;
+}
+
+/* return the number of process es in our session, count only until limit */
+static int running_processes_in_session(pid_t session, int limit)
+{
+ DIR *dir;
+ struct dirent *dent;
+ int running = 0;
+
+ dir = opendir("/proc");
+ if (!dir)
+ return -1;
+
+ /* read process info from /proc */
+ for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+ int f;
+ char procdir[64];
+ char line[256];
+ const char *pos;
+ char state;
+ pid_t ppid, pgrp, sess;
+ int len;
+
+ if (!isdigit(dent->d_name[0]))
+ continue;
+
+ snprintf(procdir, sizeof(procdir), "/proc/%s/stat", dent->d_name);
+ procdir[sizeof(procdir)-1] = '\0';
+
+ f = open(procdir, O_RDONLY);
+ if (f == -1)
+ continue;
+
+ len = read(f, line, sizeof(line)-1);
+ close(f);
+
+ if (len <= 0)
+ continue;
+ else
+ line[len] = '\0';
+
+ /* skip ugly program name */
+ pos = strrchr(line, ')') + 2;
+ if (pos == NULL)
+ continue;
+
+ if (sscanf(pos, "%c %d %d %d ", &state, &ppid, &pgrp, &sess) != 4)
+ continue;
+
+ /* count only processes in our session */
+ if (sess != session)
+ continue;
+
+ /* count only running, no sleeping processes */
+ if (state != 'R')
+ continue;
+
+ running++;
+ if (limit > 0 && running >= limit)
+ break;
}
+ closedir(dir);
+
+ return running;
}
-static void msg_move_exec(struct hotplug_msg *msg)
+static int compare_devpath(const char *running, const char *waiting)
{
- list_move_tail(&msg->list, &exec_list);
- run_exec_q = 1;
- expected_seqnum = msg->seqnum+1;
- dbg("moved seq %llu to exec, next expected is %llu",
- msg->seqnum, expected_seqnum);
+ int i;
+
+ for (i = 0; i < PATH_SIZE; 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 */
+ if (running[i] != waiting[i])
+ break;
+ }
+
+ return 0;
}
-/* msg queue management routine handles the timeouts and dispatches the events */
-static void msg_queue_manager()
+/* returns still running task for the same device, its parent or its physical device */
+static int running_with_devpath(struct uevent_msg *msg, int limit)
{
- struct hotplug_msg *loop_msg;
- struct hotplug_msg *tmp_msg;
- struct sysinfo info;
- long msg_age = 0;
-
- dbg("msg queue manager, next expected is %llu", expected_seqnum);
-recheck:
- list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, list) {
- /* move event with expected sequence to the exec list */
- if (loop_msg->seqnum == expected_seqnum) {
- msg_move_exec(loop_msg);
- continue;
+ struct uevent_msg *loop_msg;
+ int childs_count = 0;
+
+ list_for_each_entry(loop_msg, &running_list, node) {
+ if (limit && childs_count++ > limit) {
+ dbg("%llu, maximum number (%i) of child reached", msg->seqnum, childs_count);
+ return 1;
}
- /* move event with expired timeout to the exec list */
- sysinfo(&info);
- msg_age = info.uptime - loop_msg->queue_time;
- dbg("seq %llu is %li seconds old", loop_msg->seqnum, msg_age);
- if (msg_age > EVENT_TIMEOUT_SEC-1) {
- msg_move_exec(loop_msg);
- goto recheck;
- } else {
- break;
+ /* return running parent/child device event */
+ if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
+ dbg("%llu, child device event still running %llu (%s)",
+ msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
+ return 2;
}
+
+ /* return running physical device event */
+ if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
+ if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0) {
+ dbg("%llu, physical device event still running %llu (%s)",
+ msg->seqnum, loop_msg->seqnum, loop_msg->devpath);
+ return 3;
+ }
}
- msg_dump_queue();
+ return 0;
+}
+
+/* exec queue management routine executes the events and serializes events in the same sequence */
+static void msg_queue_manager(void)
+{
+ struct uevent_msg *loop_msg;
+ struct uevent_msg *tmp_msg;
+ int running;
- /* set timeout for remaining queued events */
- if (list_empty(&msg_list) == 0) {
- struct itimerval itv = {{0, 0}, {EVENT_TIMEOUT_SEC - msg_age, 0}};
- dbg("next event expires in %li seconds", EVENT_TIMEOUT_SEC - msg_age);
- setitimer(ITIMER_REAL, &itv, 0);
+ if (list_empty(&exec_list))
+ return;
+
+ running = running_processes();
+ dbg("%d processes runnning on system", running);
+ if (running < 0)
+ running = max_childs_running;
+
+ list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, node) {
+ /* check running processes in our session and possibly throttle */
+ if (running >= max_childs_running) {
+ running = running_processes_in_session(sid, max_childs_running+10);
+ dbg("at least %d processes running in session", running);
+ if (running >= max_childs_running) {
+ dbg("delay seq %llu, too many processes already running", loop_msg->seqnum);
+ return;
+ }
+ }
+
+ /* don't run two processes for the same devpath and wait for the parent*/
+ if (running_with_devpath(loop_msg, max_childs)) {
+ dbg("delay seq %llu (%s)", loop_msg->seqnum, loop_msg->devpath);
+ continue;
+ }
+
+ /* move event to run list */
+ list_move_tail(&loop_msg->node, &running_list);
+ udev_event_run(loop_msg);
+ running++;
+ dbg("moved seq %llu to running list", loop_msg->seqnum);
}
}
-/* receive the msg, do some basic sanity checks, and queue it */
-static void handle_msg(int sock)
+static struct uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size)
{
- struct hotplug_msg *msg;
- int retval;
+ int bufpos;
+ int i;
+ struct uevent_msg *msg;
+ int major = 0;
+ int minor = 0;
+
+ msg = malloc(sizeof(struct uevent_msg) + buf_size);
+ if (msg == NULL)
+ return NULL;
+ memset(msg, 0x00, sizeof(struct uevent_msg) + buf_size);
+
+ /* copy environment buffer and reconstruct envp */
+ memcpy(msg->envbuf, buf, buf_size);
+ bufpos = 0;
+ for (i = 0; (bufpos < buf_size) && (i < UEVENT_NUM_ENVP-2); i++) {
+ int keylen;
+ char *key;
+
+ key = &msg->envbuf[bufpos];
+ keylen = strlen(key);
+ msg->envp[i] = key;
+ bufpos += keylen + 1;
+ dbg("add '%s' to msg.envp[%i]", msg->envp[i], i);
+
+ /* remember some keys for further processing */
+ if (strncmp(key, "ACTION=", 7) == 0)
+ msg->action = &key[7];
+ else if (strncmp(key, "DEVPATH=", 8) == 0)
+ msg->devpath = &key[8];
+ else if (strncmp(key, "SUBSYSTEM=", 10) == 0)
+ msg->subsystem = &key[10];
+ else if (strncmp(key, "SEQNUM=", 7) == 0)
+ msg->seqnum = strtoull(&key[7], NULL, 10);
+ else if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
+ msg->physdevpath = &key[12];
+ else if (strncmp(key, "MAJOR=", 6) == 0)
+ major = strtoull(&key[6], NULL, 10);
+ else if (strncmp(key, "MINOR=", 6) == 0)
+ minor = strtoull(&key[6], NULL, 10);
+ else if (strncmp(key, "TIMEOUT=", 8) == 0)
+ msg->timeout = strtoull(&key[8], NULL, 10);
+ }
+ msg->devt = makedev(major, minor);
+ msg->envp[i++] = "UDEVD_EVENT=1";
+ msg->envp[i] = NULL;
+
+ if (msg->devpath == NULL || msg->action == NULL) {
+ info("DEVPATH or ACTION missing, ignore message");
+ free(msg);
+ return NULL;
+ }
+ return msg;
+}
+
+/* receive the udevd message from userspace */
+static struct uevent_msg *get_udevd_msg(void)
+{
+ static struct udevd_msg usend_msg;
+ struct uevent_msg *msg;
+ ssize_t size;
struct msghdr smsg;
struct cmsghdr *cmsg;
struct iovec iov;
struct ucred *cred;
char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+ int envbuf_size;
+ int *intval;
- msg = msg_create();
- if (msg == NULL) {
- dbg("unable to store message");
- return;
- }
-
- iov.iov_base = msg;
- iov.iov_len = sizeof(struct hotplug_msg);
+ memset(&usend_msg, 0x00, sizeof(struct udevd_msg));
+ iov.iov_base = &usend_msg;
+ iov.iov_len = sizeof(struct udevd_msg);
memset(&smsg, 0x00, sizeof(struct msghdr));
smsg.msg_iov = &iov;
smsg.msg_control = cred_msg;
smsg.msg_controllen = sizeof(cred_msg);
- retval = recvmsg(sock, &smsg, 0);
- if (retval < 0) {
+ size = recvmsg(udevd_sock, &smsg, 0);
+ if (size < 0) {
if (errno != EINTR)
- dbg("unable to receive message");
- return;
+ err("unable to receive user udevd message: %s", strerror(errno));
+ return NULL;
}
cmsg = CMSG_FIRSTHDR(&smsg);
cred = (struct ucred *) CMSG_DATA(cmsg);
if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
- dbg("no sender credentials received, message ignored");
- goto skip;
+ err("no sender credentials received, message ignored");
+ return NULL;
}
if (cred->uid != 0) {
- dbg("sender uid=%i, message ignored", cred->uid);
- goto skip;
+ err("sender uid=%i, message ignored", cred->uid);
+ return NULL;
}
- if (strncmp(msg->magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
- dbg("message magic '%s' doesn't match, ignore it", msg->magic);
- goto skip;
+ if (strncmp(usend_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
+ err("message magic '%s' doesn't match, ignore it", usend_msg.magic);
+ return NULL;
}
- /* if no seqnum is given, we move straight to exec queue */
- if (msg->seqnum == 0) {
- list_add(&msg->list, &exec_list);
- run_exec_q = 1;
- } else {
- msg_queue_insert(msg);
+ switch (usend_msg.type) {
+ case UDEVD_UEVENT_UDEVSEND:
+ info("udevd event message received");
+ envbuf_size = size - offsetof(struct udevd_msg, envbuf);
+ dbg("envbuf_size=%i", envbuf_size);
+ msg = get_msg_from_envbuf(usend_msg.envbuf, envbuf_size);
+ if (msg == NULL)
+ return NULL;
+ msg->type = usend_msg.type;
+ return msg;
+ case UDEVD_STOP_EXEC_QUEUE:
+ info("udevd message (STOP_EXEC_QUEUE) received");
+ stop_exec_q = 1;
+ break;
+ case UDEVD_START_EXEC_QUEUE:
+ info("udevd message (START_EXEC_QUEUE) received");
+ stop_exec_q = 0;
+ msg_queue_manager();
+ break;
+ case UDEVD_SET_LOG_LEVEL:
+ intval = (int *) usend_msg.envbuf;
+ info("udevd message (SET_LOG_PRIORITY) received, udev_log_priority=%i", *intval);
+ udev_log_priority = *intval;
+ sprintf(udev_log, "UDEV_LOG=%i", udev_log_priority);
+ putenv(udev_log);
+ break;
+ case UDEVD_SET_MAX_CHILDS:
+ intval = (int *) usend_msg.envbuf;
+ info("udevd message (UDEVD_SET_MAX_CHILDS) received, max_childs=%i", *intval);
+ max_childs = *intval;
+ break;
+ case UDEVD_RELOAD_RULES:
+ info("udevd message (RELOAD_RULES) received");
+ reload_config = 1;
+ break;
+ default:
+ dbg("unknown message type");
}
- return;
-
-skip:
- free(msg);
- return;
+ return NULL;
}
-asmlinkage static void sig_handler(int signum)
+/* receive the kernel user event message and do some sanity checks */
+static struct uevent_msg *get_netlink_msg(void)
{
- int rc;
+ struct uevent_msg *msg;
+ int bufpos;
+ ssize_t size;
+ static char buffer[UEVENT_BUFFER_SIZE+512];
+ char *pos;
+
+ size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
+ if (size < 0) {
+ if (errno != EINTR)
+ err("unable to receive kernel netlink message: %s", strerror(errno));
+ return NULL;
+ }
+
+ if ((size_t)size > sizeof(buffer)-1)
+ size = sizeof(buffer)-1;
+ buffer[size] = '\0';
+ dbg("uevent_size=%zi", size);
+
+ /* start of event payload */
+ bufpos = strlen(buffer)+1;
+ msg = get_msg_from_envbuf(&buffer[bufpos], size-bufpos);
+ if (msg == NULL)
+ return NULL;
+ msg->type = UDEVD_UEVENT_NETLINK;
+
+ /* validate message */
+ pos = strchr(buffer, '@');
+ if (pos == NULL) {
+ err("invalid uevent '%s'", buffer);
+ free(msg);
+ return NULL;
+ }
+ pos[0] = '\0';
+ if (msg->action == NULL) {
+ info("no ACTION in payload found, skip event '%s'", buffer);
+ free(msg);
+ return NULL;
+ }
+
+ if (strcmp(msg->action, buffer) != 0) {
+ err("ACTION in payload does not match uevent, skip event '%s'", buffer);
+ free(msg);
+ return NULL;
+ }
+
+ return msg;
+}
+
+static void asmlinkage sig_handler(int signum)
+{
switch (signum) {
case SIGINT:
case SIGTERM:
- exit(20 + signum);
- break;
- case SIGALRM:
- /* set flag, then write to pipe if needed */
- run_msg_q = 1;
- goto do_write;
+ udev_exit = 1;
break;
case SIGCHLD:
/* set flag, then write to pipe if needed */
- children_waiting = 1;
- goto do_write;
+ sigchilds_waiting = 1;
+ break;
+ case SIGHUP:
+ reload_config = 1;
break;
- default:
- dbg("unhandled signal %d", signum);
- return;
- }
-
-do_write:
- /* if pipe is empty, write to pipe to force select to return
- * immediately when it gets called
- */
- if (!sig_flag) {
- rc = write(pipefds[1],&signum,sizeof(signum));
- if (rc < 0)
- dbg("unable to write to pipe");
- else
- sig_flag = 1;
}
+
+ /* write to pipe, which will wakeup select() in our mainloop */
+ write(signal_pipe[WRITE_END], "", 1);
}
-static void udev_done(int pid)
+static void udev_done(int pid, int exitstatus)
{
/* find msg associated with pid and delete it */
- struct hotplug_msg *msg;
+ struct uevent_msg *msg;
- list_for_each_entry(msg, &running_list, list) {
+ list_for_each_entry(msg, &running_list, node) {
if (msg->pid == pid) {
- dbg("<== exec seq %llu came back", msg->seqnum);
- run_queue_delete(msg);
+ info("seq %llu, pid [%d] exit with %i, %ld seconds old", msg->seqnum, msg->pid,
+ exitstatus, time(NULL) - msg->queue_time);
+ msg->exitstatus = exitstatus;
+ msg_queue_delete(msg);
- /* we want to run the exec queue manager since there may
- * be events waiting with the devpath of the one that
- * just finished
- */
+ /* there may be events waiting with the same devpath */
run_exec_q = 1;
return;
}
}
}
-static void reap_kids()
+static void reap_sigchilds(void)
{
- /* reap all dead children */
- while(1) {
- int pid = waitpid(-1, 0, WNOHANG);
- if ((pid == -1) || (pid == 0))
+ pid_t pid;
+ int status;
+
+ while (1) {
+ pid = waitpid(-1, &status, WNOHANG);
+ if (pid <= 0)
break;
- udev_done(pid);
+ if (WIFEXITED(status))
+ status = WEXITSTATUS(status);
+ else if (WIFSIGNALED(status))
+ status = WTERMSIG(status) + 128;
+ else
+ status = 0;
+ udev_done(pid, status);
}
}
-/* just read everything from the pipe and clear the flag,
- * the useful flags were set in the signal handler
- */
-static void user_sighandler()
+static int init_udevd_socket(void)
{
- int sig;
- while(1) {
- int rc = read(pipefds[0],&sig,sizeof(sig));
- if (rc < 0)
- break;
+ struct sockaddr_un saddr;
+ const int buffersize = 16 * 1024 * 1024;
+ socklen_t addrlen;
+ const int feature_on = 1;
+ int retval;
- sig_flag = 0;
+ memset(&saddr, 0x00, sizeof(saddr));
+ saddr.sun_family = AF_LOCAL;
+ /* use abstract namespace for socket path */
+ strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH);
+ addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1;
+
+ udevd_sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
+ if (udevd_sock == -1) {
+ err("error getting socket: %s", strerror(errno));
+ return -1;
}
+
+ /* set receive buffersize */
+ setsockopt(udevd_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
+
+ /* the bind takes care of ensuring only one copy running */
+ retval = bind(udevd_sock, (struct sockaddr *) &saddr, addrlen);
+ if (retval < 0) {
+ err("bind failed: %s", strerror(errno));
+ return -1;
+ }
+
+ /* enable receiving of the sender credentials */
+ setsockopt(udevd_sock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on));
+
+ return 0;
}
+static int init_uevent_netlink_sock(void)
+{
+ struct sockaddr_nl snl;
+ const int buffersize = 16 * 1024 * 1024;
+ int retval;
+
+ memset(&snl, 0x00, sizeof(struct sockaddr_nl));
+ snl.nl_family = AF_NETLINK;
+ snl.nl_pid = getpid();
+ snl.nl_groups = 0xffffffff;
+
+ uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
+ if (uevent_netlink_sock == -1) {
+ err("error getting socket: %s", strerror(errno));
+ return -1;
+ }
+
+ /* set receive buffersize */
+ setsockopt(uevent_netlink_sock, SOL_SOCKET, SO_RCVBUFFORCE, &buffersize, sizeof(buffersize));
+
+ retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
+ if (retval < 0) {
+ err("bind failed: %s", strerror(errno));
+ close(uevent_netlink_sock);
+ uevent_netlink_sock = -1;
+ return -1;
+ }
+ return 0;
+}
-int main(int argc, char *argv[])
+int main(int argc, char *argv[], char *envp[])
{
- int ssock, maxsockplus;
- struct sockaddr_un saddr;
- socklen_t addrlen;
- int retval, fd;
- const int on = 1;
+ int retval;
+ int fd;
struct sigaction act;
fd_set readfds;
+ const char *value;
+ int daemonize = 0;
+ int i;
+ int rc = 0;
+ int maxfd;
+
+ /* redirect std fd's, if the kernel forks us, we don't have them at all */
+ fd = open("/dev/null", O_RDWR);
+ if (fd >= 0) {
+ if (fd != STDIN_FILENO)
+ dup2(fd, STDIN_FILENO);
+ if (fd != STDOUT_FILENO)
+ dup2(fd, STDOUT_FILENO);
+ if (fd != STDERR_FILENO)
+ dup2(fd, STDERR_FILENO);
+ if (fd > STDERR_FILENO)
+ close(fd);
+ }
- init_logging("udevd");
+ logging_init("udevd");
+ if (fd < 0)
+ err("fatal, could not open /dev/null: %s", strerror(errno));
+
+ udev_config_init();
dbg("version %s", UDEV_VERSION);
if (getuid() != 0) {
- dbg("need to be root, exit");
- exit(1);
+ err("need to be root, exit");
+ goto exit;
}
- /* make sure we are at top of dir */
- chdir("/");
- umask( umask( 077 ) | 022 );
- /* Set fds to dev/null */
- fd = open( "/dev/null", O_RDWR );
- if ( fd < 0 ) {
- dbg("error opening /dev/null %s", strerror(errno));
- exit(1);
+
+ /* parse commandline options */
+ for (i = 1 ; i < argc; i++) {
+ char *arg = argv[i];
+ if (strcmp(arg, "--daemon") == 0 || strcmp(arg, "-d") == 0) {
+ info("will daemonize");
+ daemonize = 1;
+ }
+ if (strcmp(arg, "--stop-exec-queue") == 0) {
+ info("will not execute events until START_EXEC_QUEUE is received");
+ stop_exec_q = 1;
+ }
+ }
+
+ /* init sockets to receive events */
+ if (init_udevd_socket() < 0) {
+ if (errno == EADDRINUSE) {
+ err("another udevd running, exit");
+ rc = 1;
+ } else {
+ err("error initializing udevd socket: %s", strerror(errno));
+ rc = 2;
+ }
+ goto exit;
+ }
+
+ if (init_uevent_netlink_sock() < 0) {
+ err("uevent socket not available");
+ rc = 3;
+ goto exit;
+ }
+
+ /* parse the rules and keep it in memory */
+ sysfs_init();
+ udev_rules_init(&rules, 1);
+
+ if (daemonize) {
+ pid_t pid;
+
+ pid = fork();
+ switch (pid) {
+ case 0:
+ dbg("daemonized fork running");
+ break;
+ case -1:
+ err("fork of daemon failed: %s", strerror(errno));
+ rc = 4;
+ goto exit;
+ default:
+ dbg("child [%u] running, parent exits", pid);
+ goto exit;
+ }
}
- dup2(fd, 0);
- dup2(fd, 1);
- dup2(fd, 2);
- if (fd > 2)
+
+ /* set scheduling priority for the daemon */
+ setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
+
+ chdir("/");
+ umask(022);
+
+ /* become session leader */
+ sid = setsid();
+ dbg("our session is %d", sid);
+
+ /* OOM_DISABLE == -17 */
+ fd = open("/proc/self/oom_adj", O_RDWR);
+ if (fd < 0)
+ err("error disabling OOM: %s", strerror(errno));
+ else {
+ write(fd, "-17", 3);
close(fd);
- /* Get new session id so stray signals don't come our way. */
- setsid();
+ }
/* setup signal handler pipe */
- retval = pipe(pipefds);
+ retval = pipe(signal_pipe);
if (retval < 0) {
- dbg("error getting pipes: %s", strerror(errno));
- exit(1);
+ err("error getting pipes: %s", strerror(errno));
+ goto exit;
}
- retval = fcntl(pipefds[0], F_SETFL, O_NONBLOCK);
+ retval = fcntl(signal_pipe[READ_END], F_GETFL, 0);
if (retval < 0) {
- dbg("error fcntl on read pipe: %s", strerror(errno));
- exit(1);
+ err("error fcntl on read pipe: %s", strerror(errno));
+ goto exit;
}
- retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
+ retval = fcntl(signal_pipe[READ_END], F_SETFL, retval | O_NONBLOCK);
if (retval < 0) {
- dbg("error fcntl on read pipe: %s", strerror(errno));
- exit(1);
+ err("error fcntl on read pipe: %s", strerror(errno));
+ goto exit;
}
- retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK);
+ retval = fcntl(signal_pipe[WRITE_END], F_GETFL, 0);
if (retval < 0) {
- dbg("error fcntl on write pipe: %s", strerror(errno));
- exit(1);
+ err("error fcntl on write pipe: %s", strerror(errno));
+ goto exit;
}
- retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC);
+ retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
if (retval < 0) {
- dbg("error fcntl on write pipe: %s", strerror(errno));
- exit(1);
+ err("error fcntl on write pipe: %s", strerror(errno));
+ goto exit;
}
-
/* set signal handlers */
- act.sa_handler = sig_handler;
+ memset(&act, 0x00, sizeof(struct sigaction));
+ act.sa_handler = (void (*)(int)) sig_handler;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_RESTART;
sigaction(SIGINT, &act, NULL);
sigaction(SIGTERM, &act, NULL);
- sigaction(SIGALRM, &act, NULL);
sigaction(SIGCHLD, &act, NULL);
+ sigaction(SIGHUP, &act, NULL);
- memset(&saddr, 0x00, sizeof(saddr));
- saddr.sun_family = AF_LOCAL;
- /* use abstract namespace for socket path */
- strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH);
- addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1;
+ /* watch rules directory */
+ inotify_fd = inotify_init();
+ if (inotify_fd > 0)
+ inotify_add_watch(inotify_fd, udev_rules_filename, IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
- ssock = socket(AF_LOCAL, SOCK_DGRAM, 0);
- if (ssock == -1) {
- dbg("error getting socket, exit");
- exit(1);
- }
-
- /* the bind takes care of ensuring only one copy running */
- retval = bind(ssock, (struct sockaddr *) &saddr, addrlen);
- if (retval < 0) {
- dbg("bind failed, exit");
- goto exit;
- }
- retval = fcntl(ssock, F_SETFD, FD_CLOEXEC);
- if (retval < 0) {
- dbg("error fcntl on ssock: %s", strerror(errno));
- exit(1);
- }
-
- /* enable receiving of the sender credentials */
- setsockopt(ssock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
-
- /* possible override of udev binary, used for testing */
- udev_bin = getenv("UDEV_BIN");
- if (udev_bin != NULL)
- dbg("udev binary is set to '%s'", udev_bin);
+ /* maximum limit of forked childs */
+ value = getenv("UDEVD_MAX_CHILDS");
+ if (value)
+ max_childs = strtoul(value, NULL, 10);
else
- udev_bin = UDEV_BIN;
-
- FD_ZERO(&readfds);
- FD_SET(ssock, &readfds);
- FD_SET(pipefds[0], &readfds);
- maxsockplus = ssock+1;
- while (1) {
- fd_set workreadfds = readfds;
- retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL);
+ max_childs = UDEVD_MAX_CHILDS;
+ info("initialize max_childs to %u", max_childs);
- if (retval < 0) {
+ /* start to throttle forking if maximum number of _running_ childs is reached */
+ value = getenv("UDEVD_MAX_CHILDS_RUNNING");
+ if (value)
+ max_childs_running = strtoull(value, NULL, 10);
+ else
+ max_childs_running = UDEVD_MAX_CHILDS_RUNNING;
+ info("initialize max_childs_running to %u", max_childs_running);
+
+ /* clear environment for forked event processes */
+ clearenv();
+
+ /* export log_priority , as called programs may want to follow that setting */
+ sprintf(udev_log, "UDEV_LOG=%i", udev_log_priority);
+ putenv(udev_log);
+
+ maxfd = udevd_sock;
+ maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
+ maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
+ maxfd = UDEV_MAX(maxfd, inotify_fd);
+
+ while (!udev_exit) {
+ struct uevent_msg *msg;
+ int fdcount;
+
+ FD_ZERO(&readfds);
+ FD_SET(signal_pipe[READ_END], &readfds);
+ FD_SET(udevd_sock, &readfds);
+ FD_SET(uevent_netlink_sock, &readfds);
+ if (inotify_fd > 0)
+ FD_SET(inotify_fd, &readfds);
+
+ fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
+ if (fdcount < 0) {
if (errno != EINTR)
- dbg("error in select: %s", strerror(errno));
+ err("error in select: %s", strerror(errno));
continue;
}
- if (FD_ISSET(ssock, &workreadfds))
- handle_msg(ssock);
-
- if (FD_ISSET(pipefds[0], &workreadfds))
- user_sighandler();
+ /* get user socket message */
+ if (FD_ISSET(udevd_sock, &readfds)) {
+ msg = get_udevd_msg();
+ if (msg)
+ msg_queue_insert(msg);
+ }
- if (children_waiting) {
- children_waiting = 0;
- reap_kids();
+ /* get kernel netlink message */
+ if (FD_ISSET(uevent_netlink_sock, &readfds)) {
+ msg = get_netlink_msg();
+ if (msg)
+ msg_queue_insert(msg);
}
- if (run_msg_q) {
- run_msg_q = 0;
- msg_queue_manager();
+ /* received a signal, clear our notification pipe */
+ if (FD_ISSET(signal_pipe[READ_END], &readfds)) {
+ char buf[256];
+
+ read(signal_pipe[READ_END], &buf, sizeof(buf));
}
- if (run_exec_q) {
- /* this is tricky. exec_queue_manager() loops over exec_list, and
- * calls running_with_devpath(), which loops over running_list. This gives
- * O(N*M), which can get *nasty*. Clean up running_list before
- * calling exec_queue_manager().
- */
- if (children_waiting) {
- children_waiting = 0;
- reap_kids();
+ /* rules directory inotify watch */
+ if ((inotify_fd > 0) && FD_ISSET(inotify_fd, &readfds)) {
+ int nbytes;
+
+ /* discard all possible events, we can just reload the config */
+ if ((ioctl(inotify_fd, FIONREAD, &nbytes) == 0) && nbytes) {
+ char *buf;
+
+ reload_config = 1;
+ buf = malloc(nbytes);
+ if (!buf) {
+ err("error getting buffer for inotify, disable watching");
+ close(inotify_fd);
+ inotify_fd = -1;
+ }
+ read(inotify_fd, buf, nbytes);
+ free(buf);
}
+ }
+
+ /* rules changed, set by inotify or a signal*/
+ if (reload_config) {
+ reload_config = 0;
+ udev_rules_cleanup(&rules);
+ udev_rules_init(&rules, 1);
+ }
+ /* forked child has returned */
+ if (sigchilds_waiting) {
+ sigchilds_waiting = 0;
+ reap_sigchilds();
+ }
+
+ if (run_exec_q) {
run_exec_q = 0;
- exec_queue_manager();
+ if (!stop_exec_q)
+ msg_queue_manager();
}
}
+
exit:
- close(ssock);
- exit(1);
+ udev_rules_cleanup(&rules);
+ sysfs_cleanup();
+
+ if (signal_pipe[READ_END] > 0)
+ close(signal_pipe[READ_END]);
+ if (signal_pipe[WRITE_END] > 0)
+ close(signal_pipe[WRITE_END]);
+
+ if (udevd_sock > 0)
+ close(udevd_sock);
+ if (inotify_fd > 0)
+ close(inotify_fd);
+ if (uevent_netlink_sock > 0)
+ close(uevent_netlink_sock);
+
+ logging_close();
+
+ return rc;
}