chiark / gitweb /
path_id: prepare for new sysfs layout
[elogind.git] / udevd.c
diff --git a/udevd.c b/udevd.c
index 6fb0bd9..02c4887 100644 (file)
--- a/udevd.c
+++ b/udevd.c
@@ -1,5 +1,5 @@
 /*
- * udevd.c - hotplug event serializer
+ * udevd.c - event listener and serializer
  *
  * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
  * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
 #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/time.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/un.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_libc_wrapper.h"
 #include "udev.h"
-#include "udev_version.h"
-#include "udev_utils.h"
+#include "udev_rules.h"
 #include "udevd.h"
-#include "logging.h"
 
-/* global variables*/
+static struct udev_rules rules;
 static int udevd_sock;
-static int uevent_nl_sock;
+static int uevent_netlink_sock;
+static int inotify_fd;
 static pid_t sid;
 
-static int pipefds[2];
+static int signal_pipe[2] = {-1, -1};
 static volatile int sigchilds_waiting;
-static volatile int run_msg_q;
-static volatile int sig_flag;
-static int init_phase = 1;
+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_sigchilds(void);
-
-static char *udev_bin;
-static unsigned long long expected_seqnum;
-static int event_timeout;
-static int max_childs;
-static int max_childs_running;
-
 
 #ifdef USE_LOG
-void log_message (int priority, const char *format, ...)
+void log_message(int priority, const char *format, ...)
 {
        va_list args;
 
@@ -91,111 +80,236 @@ void log_message (int priority, const char *format, ...)
 }
 #endif
 
-static void msg_dump_queue(void)
+static void asmlinkage udev_event_sig_handler(int signum)
 {
-#ifdef DEBUG
-       struct uevent_msg *msg;
-
-       list_for_each_entry(msg, &msg_list, node)
-               dbg("sequence %llu in queue", msg->seqnum);
-#endif
+       if (signum == SIGALRM)
+               exit(1);
 }
 
-static void run_queue_delete(struct uevent_msg *msg)
+static int udev_event_process(struct uevent_msg *msg)
 {
-       list_del(&msg->node);
-       free(msg);
+       struct sigaction act;
+       struct udevice *udev;
+       int i;
+       int retval;
+
+       /* 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);
+
+       /* 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:")], udev->dev->devpath, udev->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 uevent_msg *msg)
+enum event_state {
+       EVENT_QUEUED,
+       EVENT_FINISHED,
+       EVENT_FAILED,
+};
+
+static void export_event_state(struct uevent_msg *msg, enum event_state state)
 {
+       char filename[PATH_SIZE];
+       char filename_failed[PATH_SIZE];
+       char target[PATH_SIZE];
+       size_t start, end, i;
        struct uevent_msg *loop_msg;
-       struct sysinfo info;
 
-       if (msg->seqnum == 0) {
-               dbg("no SEQNUM, move straight to the exec queue");
-               list_add(&msg->node, &exec_list);
-               run_exec_q = 1;
+       /* 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;
 
-       /* store timestamp of queuing */
-       sysinfo(&info);
-       msg->queue_time = info.uptime;
+               list_for_each_entry(loop_msg, &exec_list, node)
+                       if (loop_msg->devpath && strcmp(loop_msg->devpath, msg->devpath) == 0)
+                               return;
 
-       /* with the first event we provide a phase of shorter timeout */
-       if (init_phase) {
-               static long init_time;
+               /* move failed events to the failed directory */
+               if (state == EVENT_FAILED) {
+                       create_path(filename_failed);
+                       rename(filename, filename_failed);
+               } else {
+                       unlink(filename);
+               }
 
-               if (init_time == 0)
-                       init_time = info.uptime;
-               if (info.uptime - init_time >= UDEVD_INIT_TIME)
-                       init_phase = 0;
-       }
+               /* clean up the queue directory */
+               delete_path(filename);
 
-       /* don't delay messages with timeout set */
-       if (msg->timeout) {
-               dbg("move seq %llu with timeout %u to exec queue", msg->seqnum, msg->timeout);
-               list_add(&msg->node, &exec_list);
-               run_exec_q = 1;
                return;
        }
+}
 
-       /* sort message by sequence number into list */
-       list_for_each_entry_reverse(loop_msg, &msg_list, node) {
-               if (loop_msg->seqnum < msg->seqnum)
-                       break;
-
-               if (loop_msg->seqnum == msg->seqnum) {
-                       dbg("ignoring duplicate message seq %llu", msg->seqnum);
-                       free(msg);
-                       return;
-               }
-       }
-       list_add(&msg->node, &loop_msg->node);
-       info("seq %llu queued, devpath '%s'", msg->seqnum, msg->devpath);
+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 execute_udev(struct uevent_msg *msg)
+static void udev_event_run(struct uevent_msg *msg)
 {
-       char *const argv[] = { "udev", msg->subsystem, NULL };
        pid_t pid;
-       struct sysinfo info;
+       int retval;
 
        pid = fork();
        switch (pid) {
        case 0:
                /* child */
-               if (uevent_nl_sock != -1)
-                       close(uevent_nl_sock);
+               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);
-               execve(udev_bin, argv, msg->envp);
-               err("exec of child failed");
-               _exit(1);
-               break;
+               retval = udev_event_process(msg);
+               info("seq %llu finished", msg->seqnum);
+
+               logging_close();
+               if (retval)
+                       exit(1);
+               exit(0);
        case -1:
-               err("fork of child failed");
-               run_queue_delete(msg);
+               err("fork of child failed: %s", strerror(errno));
+               msg_queue_delete(msg);
                break;
        default:
                /* get SIGCHLD in main loop */
-               sysinfo(&info);
-               info("seq %llu forked, pid %d, %ld seconds old",
-                    msg->seqnum, pid, info.uptime - msg->queue_time);
+               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;
        }
 }
 
+static void msg_queue_insert(struct uevent_msg *msg)
+{
+       char filename[PATH_SIZE];
+       int fd;
+
+       msg->queue_time = time(NULL);
+
+       strlcpy(filename, udev_root, sizeof(filename));
+       strlcat(filename, "/" EVENT_SEQNUM, sizeof(filename));
+       fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
+       if (fd >= 0) {
+               char str[32];
+               int len;
+
+               len = sprintf(str, "%llu\n", msg->seqnum);
+               write(fd, str, len);
+               close(fd);
+       }
+
+       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;
+}
+
+/* runs event and removes event from run queue when finished */
 static int running_processes(void)
 {
        int f;
@@ -208,7 +322,7 @@ static int running_processes(void)
        if (f == -1)
                return -1;
 
-       len = read(f, buf, sizeof(buf));
+       len = read(f, buf, sizeof(buf)-1);
        close(f);
 
        if (len <= 0)
@@ -257,7 +371,7 @@ static int running_processes_in_session(pid_t session, int limit)
                if (f == -1)
                        continue;
 
-               len = read(f, line, sizeof(line));
+               len = read(f, line, sizeof(line)-1);
                close(f);
 
                if (len <= 0)
@@ -321,20 +435,11 @@ static int running_with_devpath(struct uevent_msg *msg, int limit)
        struct uevent_msg *loop_msg;
        int childs_count = 0;
 
-       if (msg->devpath == NULL)
-               return 0;
-
-       /* skip any events with a timeout set */
-       if (msg->timeout != 0)
-               return 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;
                }
-               if (loop_msg->devpath == NULL)
-                       continue;
 
                /* return running parent/child device event */
                if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
@@ -356,12 +461,15 @@ static int running_with_devpath(struct uevent_msg *msg, int limit)
 }
 
 /* exec queue management routine executes the events and serializes events in the same sequence */
-static void exec_queue_manager(void)
+static void msg_queue_manager(void)
 {
        struct uevent_msg *loop_msg;
        struct uevent_msg *tmp_msg;
        int running;
 
+       if (list_empty(&exec_list))
+               return;
+
        running = running_processes();
        dbg("%d processes runnning on system", running);
        if (running < 0)
@@ -373,75 +481,22 @@ static void exec_queue_manager(void)
                        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, cause too many processes already running",
-                                   loop_msg->seqnum);
+                               dbg("delay seq %llu, too many processes already running", loop_msg->seqnum);
                                return;
                        }
                }
 
-               if (running_with_devpath(loop_msg, max_childs) == 0) {
-                       /* move event to run list */
-                       list_move_tail(&loop_msg->node, &running_list);
-                       execute_udev(loop_msg);
-                       running++;
-                       dbg("moved seq %llu to running list", loop_msg->seqnum);
-               } else
+               /* 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);
-       }
-}
-
-static void msg_move_exec(struct uevent_msg *msg)
-{
-       list_move_tail(&msg->node, &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);
-}
-
-/* msg queue management routine handles the timeouts and dispatches the events */
-static void msg_queue_manager(void)
-{
-       struct uevent_msg *loop_msg;
-       struct uevent_msg *tmp_msg;
-       struct sysinfo info;
-       long msg_age = 0;
-       int timeout = event_timeout;
-
-       dbg("msg queue manager, next expected is %llu", expected_seqnum);
-recheck:
-       sysinfo(&info);
-       list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, node) {
-               /* move event with expected sequence to the exec list */
-               if (loop_msg->seqnum == expected_seqnum) {
-                       msg_move_exec(loop_msg);
                        continue;
                }
 
-               /* limit timeout during initialization phase */
-               if (init_phase) {
-                       timeout = UDEVD_INIT_EVENT_TIMEOUT;
-                       dbg("initialization phase, limit timeout to %i seconds", UDEVD_INIT_EVENT_TIMEOUT);
-               }
-
-               /* move event with expired timeout to the exec list */
-               msg_age = info.uptime - loop_msg->queue_time;
-               dbg("seq %llu is %li seconds old", loop_msg->seqnum, msg_age);
-               if (msg_age >= timeout) {
-                       msg_move_exec(loop_msg);
-                       goto recheck;
-               } else {
-                       break;
-               }
-       }
-
-       msg_dump_queue();
-
-       /* set timeout for remaining queued events */
-       if (list_empty(&msg_list) == 0) {
-               struct itimerval itv = {{0, 0}, {timeout - msg_age, 0}};
-               dbg("next event expires in %li seconds", timeout - msg_age);
-               setitimer(ITIMER_REAL, &itv, NULL);
+               /* 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);
        }
 }
 
@@ -450,6 +505,8 @@ static struct uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size)
        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)
@@ -472,43 +529,47 @@ static struct uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size)
                /* remember some keys for further processing */
                if (strncmp(key, "ACTION=", 7) == 0)
                        msg->action = &key[7];
-
-               if (strncmp(key, "DEVPATH=", 8) == 0)
+               else if (strncmp(key, "DEVPATH=", 8) == 0)
                        msg->devpath = &key[8];
-
-               if (strncmp(key, "SUBSYSTEM=", 10) == 0)
+               else if (strncmp(key, "SUBSYSTEM=", 10) == 0)
                        msg->subsystem = &key[10];
-
-               if (strncmp(key, "SEQNUM=", 7) == 0)
+               else if (strncmp(key, "SEQNUM=", 7) == 0)
                        msg->seqnum = strtoull(&key[7], NULL, 10);
-
-               if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
+               else if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
                        msg->physdevpath = &key[12];
-
-               if (strncmp(key, "TIMEOUT=", 8) == 0)
+               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;
+       static struct udevd_msg ctrl_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;
 
-       memset(&usend_msg, 0x00, sizeof(struct udevd_msg));
-       iov.iov_base = &usend_msg;
+       memset(&ctrl_msg, 0x00, sizeof(struct udevd_msg));
+       iov.iov_base = &ctrl_msg;
        iov.iov_len = sizeof(struct udevd_msg);
 
        memset(&smsg, 0x00, sizeof(struct msghdr));
@@ -520,44 +581,52 @@ static struct uevent_msg *get_udevd_msg(void)
        size = recvmsg(udevd_sock, &smsg, 0);
        if (size <  0) {
                if (errno != EINTR)
-                       dbg("unable to receive udevd message");
+                       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) {
-               info("no sender credentials received, message ignored");
+               err("no sender credentials received, message ignored");
                return NULL;
        }
 
        if (cred->uid != 0) {
-               info("sender uid=%i, message ignored", cred->uid);
+               err("sender uid=%i, message ignored", cred->uid);
                return NULL;
        }
 
-       if (strncmp(usend_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
-               info("message magic '%s' doesn't match, ignore it", usend_msg.magic);
+       if (strncmp(ctrl_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
+               err("message magic '%s' doesn't match, ignore it", ctrl_msg.magic);
                return NULL;
        }
 
-switch (usend_msg.type) {
-       case UDEVD_UEVENT:
-               dbg("udevd message (UEVENT) 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;
-               return msg;
+       switch (ctrl_msg.type) {
        case UDEVD_STOP_EXEC_QUEUE:
-               dbg("udevd message (STOP_EXEC_QUEUE) received");
+               info("udevd message (STOP_EXEC_QUEUE) received");
                stop_exec_q = 1;
                break;
        case UDEVD_START_EXEC_QUEUE:
-               dbg("udevd message (START_EXEC_QUEUE) received");
+               info("udevd message (START_EXEC_QUEUE) received");
                stop_exec_q = 0;
-               exec_queue_manager();
+               msg_queue_manager();
+               break;
+       case UDEVD_SET_LOG_LEVEL:
+               intval = (int *) ctrl_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 *) ctrl_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");
@@ -566,49 +635,50 @@ switch (usend_msg.type) {
 }
 
 /* receive the kernel user event message and do some sanity checks */
-static struct uevent_msg *get_uevent_msg(void)
+static struct uevent_msg *get_netlink_msg(void)
 {
        struct uevent_msg *msg;
        int bufpos;
        ssize_t size;
-       static char buffer[UEVENT_BUFFER_SIZE + 512];
+       static char buffer[UEVENT_BUFFER_SIZE+512];
        char *pos;
 
-       size = recv(uevent_nl_sock, &buffer, sizeof(buffer), 0);
+       size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
        if (size <  0) {
                if (errno != EINTR)
-                       dbg("unable to receive udevd message");
+                       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=%i", size);
+       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) {
-               dbg("invalid uevent '%s'", buffer);
+               err("invalid uevent '%s'", buffer);
                free(msg);
                return NULL;
        }
        pos[0] = '\0';
 
        if (msg->action == NULL) {
-               dbg("no ACTION in payload found, skip event '%s'", buffer);
+               info("no ACTION in payload found, skip event '%s'", buffer);
                free(msg);
                return NULL;
        }
 
        if (strcmp(msg->action, buffer) != 0) {
-               dbg("ACTION in payload does not match uevent, skip event '%s'", buffer);
+               err("ACTION in payload does not match uevent, skip event '%s'", buffer);
                free(msg);
                return NULL;
        }
@@ -618,52 +688,37 @@ static struct uevent_msg *get_uevent_msg(void)
 
 static void asmlinkage sig_handler(int signum)
 {
-       int rc;
-
        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 */
                        sigchilds_waiting = 1;
-                       goto do_write;
+                       break;
+               case SIGHUP:
+                       reload_config = 1;
                        break;
        }
 
-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)
-                       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 uevent_msg *msg;
-       struct sysinfo info;
 
        list_for_each_entry(msg, &running_list, node) {
                if (msg->pid == pid) {
-                       sysinfo(&info);
-                       info("seq %llu exit, %ld sec old", msg->seqnum, info.uptime - msg->queue_time);
-                       run_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
-                        */
+                       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);
+
+                       /* there may be events waiting with the same devpath */
                        run_exec_q = 1;
                        return;
                }
@@ -672,33 +727,27 @@ static void udev_done(int pid)
 
 static void reap_sigchilds(void)
 {
-       while(1) {
-               int pid = waitpid(-1, NULL, WNOHANG);
-               if ((pid == -1) || (pid == 0))
-                       break;
-               udev_done(pid);
-       }
-}
-
-/* just read everything from the pipe and clear the flag,
- * the flags was set in the signal handler
- */
-static void user_sighandler(void)
-{
-       int sig;
+       pid_t pid;
+       int status;
 
-       while(1) {
-               int rc = read(pipefds[0], &sig, sizeof(sig));
-               if (rc < 0)
+       while (1) {
+               pid = waitpid(-1, &status, WNOHANG);
+               if (pid <= 0)
                        break;
-
-               sig_flag = 0;
+               if (WIFEXITED(status))
+                       status = WEXITSTATUS(status);
+               else if (WIFSIGNALED(status))
+                       status = WTERMSIG(status) + 128;
+               else
+                       status = 0;
+               udev_done(pid, status);
        }
 }
 
 static int init_udevd_socket(void)
 {
        struct sockaddr_un saddr;
+       const int buffersize = 16 * 1024 * 1024;
        socklen_t addrlen;
        const int feature_on = 1;
        int retval;
@@ -711,15 +760,17 @@ static int init_udevd_socket(void)
 
        udevd_sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
        if (udevd_sock == -1) {
-               err("error getting socket, %s", strerror(errno));
+               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));
-               close(udevd_sock);
+               err("bind failed: %s", strerror(errno));
                return -1;
        }
 
@@ -729,9 +780,10 @@ static int init_udevd_socket(void)
        return 0;
 }
 
-static int init_uevent_nl_sock(void)
+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));
@@ -739,38 +791,83 @@ static int init_uevent_nl_sock(void)
        snl.nl_pid = getpid();
        snl.nl_groups = 0xffffffff;
 
-       uevent_nl_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
-       if (uevent_nl_sock == -1) {
-               dbg("error getting socket, %s", strerror(errno));
+       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;
        }
 
-       retval = bind(uevent_nl_sock, (struct sockaddr *) &snl,
-                     sizeof(struct sockaddr_nl));
+       /* 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) {
-               dbg("bind failed, %s", strerror(errno));
-               close(uevent_nl_sock);
-               uevent_nl_sock = -1;
+               err("bind failed: %s", strerror(errno));
+               close(uevent_netlink_sock);
+               uevent_netlink_sock = -1;
                return -1;
        }
-
        return 0;
 }
 
+static void export_initial_seqnum(void)
+{
+       char filename[PATH_SIZE];
+       int fd;
+       char seqnum[32];
+       ssize_t len = 0;
+
+       strlcpy(filename, sysfs_path, sizeof(filename));
+       strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename));
+       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;
+       }
+       strlcpy(filename, udev_root, sizeof(filename));
+       strlcat(filename, "/" EVENT_SEQNUM, sizeof(filename));
+       create_path(filename);
+       fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644);
+       if (fd >= 0) {
+               write(fd, seqnum, len);
+               close(fd);
+       }
+}
+
 int main(int argc, char *argv[], char *envp[])
 {
-       int maxsockplus;
        int retval;
        int fd;
        struct sigaction act;
        fd_set readfds;
        const char *value;
-       int uevent_nl_active = 0;
        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);
+       }
 
        logging_init("udevd");
-       udev_init_config();
+       if (fd < 0)
+               err("fatal, could not open /dev/null: %s", strerror(errno));
+
+       udev_config_init();
        dbg("version %s", UDEV_VERSION);
 
        if (getuid() != 0) {
@@ -778,6 +875,7 @@ int main(int argc, char *argv[], char *envp[])
                goto exit;
        }
 
+       /* parse commandline options */
        for (i = 1 ; i < argc; i++) {
                char *arg = argv[i];
                if (strcmp(arg, "--daemon") == 0 || strcmp(arg, "-d") == 0) {
@@ -785,72 +883,100 @@ int main(int argc, char *argv[], char *envp[])
                        daemonize = 1;
                }
                if (strcmp(arg, "--stop-exec-queue") == 0) {
-                       info("will not execute event until START_EXEC_QUEUE is received");
+                       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);
+
+       export_initial_seqnum();
+
        if (daemonize) {
                pid_t pid;
 
                pid = fork();
                switch (pid) {
                case 0:
-                       dbg("damonized fork running");
+                       dbg("daemonized fork running");
                        break;
                case -1:
-                       err("fork of daemon failed");
+                       err("fork of daemon failed: %s", strerror(errno));
+                       rc = 4;
                        goto exit;
                default:
-                       logging_close();
-                       exit(0);
+                       dbg("child [%u] running, parent exits", pid);
+                       goto exit;
                }
        }
 
-       /* become session leader */
-       sid = setsid();
-       dbg("our session is %d", sid);
+       /* set scheduling priority for the daemon */
+       setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
 
        chdir("/");
-       umask(umask(077) | 022);
+       umask(022);
 
-       /*set a reasonable scheduling priority for the daemon */
-       setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
+       /* become session leader */
+       sid = setsid();
+       dbg("our session is %d", sid);
 
-       /* Set fds to dev/null */
-       fd = open( "/dev/null", O_RDWR );
-       if (fd >= 0)  {
-               dup2(fd, 0);
-               dup2(fd, 1);
-               dup2(fd, 2);
-               if (fd > 2)
-                       close(fd);
-       } else
-               err("error opening /dev/null %s", strerror(errno));
+       /* 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);
+       }
 
        /* setup signal handler pipe */
-       retval = pipe(pipefds);
+       retval = pipe(signal_pipe);
        if (retval < 0) {
                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) {
                err("error fcntl on read pipe: %s", strerror(errno));
                goto exit;
        }
-       retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
-       if (retval < 0)
+       retval = fcntl(signal_pipe[READ_END], F_SETFL, retval | O_NONBLOCK);
+       if (retval < 0) {
                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) {
                err("error fcntl on write pipe: %s", strerror(errno));
                goto exit;
        }
-       retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC);
-       if (retval < 0)
+       retval = fcntl(signal_pipe[WRITE_END], F_SETFL, retval | O_NONBLOCK);
+       if (retval < 0) {
                err("error fcntl on write pipe: %s", strerror(errno));
+               goto exit;
+       }
 
        /* set signal handlers */
        memset(&act, 0x00, sizeof(struct sigaction));
@@ -859,43 +985,17 @@ int main(int argc, char *argv[], char *envp[])
        act.sa_flags = SA_RESTART;
        sigaction(SIGINT, &act, NULL);
        sigaction(SIGTERM, &act, NULL);
-       sigaction(SIGALRM, &act, NULL);
        sigaction(SIGCHLD, &act, NULL);
-
-       if (init_uevent_nl_sock() < 0) {
-               dbg("uevent socket not available");
-       }
-
-       if (init_udevd_socket() < 0) {
-               if (errno == EADDRINUSE)
-                       dbg("another udevd running, exit");
-               else
-                       dbg("error initialising udevd socket: %s", strerror(errno));
-
-               goto exit;
-       }
-
-       /* override of forked udev binary, used for testing */
-       udev_bin = getenv("UDEV_BIN");
-       if (udev_bin != NULL)
-               info("udev binary is set to '%s'", udev_bin);
-       else
-               udev_bin = UDEV_BIN;
-
-       /* init of expected_seqnum value */
-       value = getenv("UDEVD_EXPECTED_SEQNUM");
-       if (value) {
-               expected_seqnum = strtoull(value, NULL, 10);
-               info("initialize expected_seqnum to %llu", expected_seqnum);
-       }
-
-       /* timeout to wait for missing events */
-       value = getenv("UDEVD_EVENT_TIMEOUT");
-       if (value)
-               event_timeout = strtoul(value, NULL, 10);
+       sigaction(SIGHUP, &act, NULL);
+
+       /* 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);
+       else if (errno == ENOSYS)
+               err("the kernel does not support inotify, udevd can't monitor configuration file changes");
        else
-               event_timeout = UDEVD_EVENT_TIMEOUT;
-       info("initialize event_timeout to %u", event_timeout);
+               err("inotify_init failed: %s", strerror(errno));
 
        /* maximum limit of forked childs */
        value = getenv("UDEVD_MAX_CHILDS");
@@ -913,76 +1013,114 @@ int main(int argc, char *argv[], char *envp[])
                max_childs_running = UDEVD_MAX_CHILDS_RUNNING;
        info("initialize max_childs_running to %u", max_childs_running);
 
-       FD_ZERO(&readfds);
-       FD_SET(udevd_sock, &readfds);
-       if (uevent_nl_sock != -1)
-               FD_SET(uevent_nl_sock, &readfds);
-       FD_SET(pipefds[0], &readfds);
-       maxsockplus = udevd_sock+1;
-       while (1) {
+       /* 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_set workreadfds = readfds;
-               retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL);
+               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);
 
-               if (retval < 0) {
+               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(udevd_sock, &workreadfds)) {
+               /* get user socket message */
+               if (FD_ISSET(udevd_sock, &readfds)) {
                        msg = get_udevd_msg();
-                       if (msg) {
-                               /* discard kernel messages if netlink is active */
-                               if (uevent_nl_active && msg->seqnum != 0) {
-                                       dbg("skip uevent_helper message, netlink is active");
-                                       free(msg);
-                                       continue;
-                               }
+                       if (msg)
                                msg_queue_insert(msg);
-                       }
                }
 
-               if (FD_ISSET(uevent_nl_sock, &workreadfds)) {
-                       msg = get_uevent_msg();
-                       if (msg) {
+               /* get kernel netlink message */
+               if (FD_ISSET(uevent_netlink_sock, &readfds)) {
+                       msg = get_netlink_msg();
+                       if (msg)
                                msg_queue_insert(msg);
-                               /* disable kernel uevent_helper with first netlink message */
-                               if (!uevent_nl_active) {
-                                       info("uevent_nl message received, disable uevent_helper messages");
-                                       uevent_nl_active = 1;
+               }
+
+               /* 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));
+               }
+
+               /* 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);
                        }
                }
 
-               if (FD_ISSET(pipefds[0], &workreadfds))
-                       user_sighandler();
+               /* 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_msg_q) {
-                       run_msg_q = 0;
-                       msg_queue_manager();
-               }
-
                if (run_exec_q) {
-                        /* clean up running_list before calling exec_queue_manager() */
-                       if (sigchilds_waiting) {
-                               sigchilds_waiting = 0;
-                               reap_sigchilds();
-                       }
-
                        run_exec_q = 0;
                        if (!stop_exec_q)
-                               exec_queue_manager();
+                               msg_queue_manager();
                }
        }
 
 exit:
+       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 1;
+
+       return rc;
 }