Fork of Original Code Base: anongit.freedesktop.org/systemd

This is the initial fork of the code base from freedsktop.org.
The code is provided here as a reference of the initial starting
point and for possible future checkouts after a large portion
of this code is removed.

Merge git://anongit.freedesktop.org/systemd/systemd

17 files changed, 6948 insertions, 0 deletions

diff --git a/src/libudev/.gitignore b/src/libudev/.gitignore
new file mode 100644
index 0000000000..0c8a5d5231
--- /dev/null
+++ b/src/libudev/.gitignore
@@ -0,0 +1 @@
+/libudev.pc
diff --git a/src/libudev/Makefile b/src/libudev/Makefile
new file mode 120000
index 0000000000..d0b0e8e008
--- /dev/null
+++ b/src/libudev/Makefile
@@ -0,0 +1 @@
+../Makefile
\ No newline at end of file
diff --git a/src/libudev/libudev-device-private.c b/src/libudev/libudev-device-private.c
new file mode 100644
index 0000000000..c123057907
--- /dev/null
+++ b/src/libudev/libudev-device-private.c
@@ -0,0 +1,192 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stddef.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+static void udev_device_tag(struct udev_device *dev, const char *tag, bool add)
+{
+        const char *id;
+        char filename[UTIL_PATH_SIZE];
+
+        id = udev_device_get_id_filename(dev);
+        if (id == NULL)
+                return;
+        util_strscpyl(filename, sizeof(filename), "/run/udev/tags/", tag, "/", id, NULL);
+
+        if (add) {
+                int fd;
+
+                mkdir_parents(filename, 0755);
+                fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
+                if (fd >= 0)
+                        close(fd);
+        } else {
+                unlink(filename);
+        }
+}
+
+int udev_device_tag_index(struct udev_device *dev, struct udev_device *dev_old, bool add)
+{
+        struct udev_list_entry *list_entry;
+        bool found;
+
+        if (add && dev_old != NULL) {
+                /* delete possible left-over tags */
+                udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(dev_old)) {
+                        const char *tag_old = udev_list_entry_get_name(list_entry);
+                        struct udev_list_entry *list_entry_current;
+
+                        found = false;
+                        udev_list_entry_foreach(list_entry_current, udev_device_get_tags_list_entry(dev)) {
+                                const char *tag = udev_list_entry_get_name(list_entry_current);
+
+                                if (streq(tag, tag_old)) {
+                                        found = true;
+                                        break;
+                                }
+                        }
+                        if (!found)
+                                udev_device_tag(dev_old, tag_old, false);
+                }
+        }
+
+        udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(dev))
+                udev_device_tag(dev, udev_list_entry_get_name(list_entry), add);
+
+        return 0;
+}
+
+static bool device_has_info(struct udev_device *udev_device)
+{
+        struct udev_list_entry *list_entry;
+
+        if (udev_device_get_devlinks_list_entry(udev_device) != NULL)
+                return true;
+        if (udev_device_get_devlink_priority(udev_device) != 0)
+                return true;
+        udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device))
+                if (udev_list_entry_get_num(list_entry))
+                        return true;
+        if (udev_device_get_tags_list_entry(udev_device) != NULL)
+                return true;
+        if (udev_device_get_watch_handle(udev_device) >= 0)
+                return true;
+        return false;
+}
+
+int udev_device_update_db(struct udev_device *udev_device)
+{
+        struct udev *udev = udev_device_get_udev(udev_device);
+        bool has_info;
+        const char *id;
+        char filename[UTIL_PATH_SIZE];
+        char filename_tmp[UTIL_PATH_SIZE];
+        FILE *f;
+        int r;
+
+        id = udev_device_get_id_filename(udev_device);
+        if (id == NULL)
+                return -1;
+
+        has_info = device_has_info(udev_device);
+        util_strscpyl(filename, sizeof(filename), "/run/udev/data/", id, NULL);
+
+        /* do not store anything for otherwise empty devices */
+        if (!has_info &&
+            major(udev_device_get_devnum(udev_device)) == 0 &&
+            udev_device_get_ifindex(udev_device) == 0) {
+                unlink(filename);
+                return 0;
+        }
+
+        /* write a database file */
+        util_strscpyl(filename_tmp, sizeof(filename_tmp), filename, ".tmp", NULL);
+        mkdir_parents(filename_tmp, 0755);
+        f = fopen(filename_tmp, "we");
+        if (f == NULL) {
+                udev_err(udev, "unable to create temporary db file '%s': %m\n", filename_tmp);
+                return -1;
+        }
+
+        /*
+         * set 'sticky' bit to indicate that we should not clean the
+         * database when we transition from initramfs to the real root
+         */
+        if (udev_device_get_db_persist(udev_device))
+                fchmod(fileno(f), 01644);
+
+        if (has_info) {
+                struct udev_list_entry *list_entry;
+
+                if (major(udev_device_get_devnum(udev_device)) > 0) {
+                        udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(udev_device))
+                                fprintf(f, "S:%s\n", udev_list_entry_get_name(list_entry) + strlen("/dev/"));
+                        if (udev_device_get_devlink_priority(udev_device) != 0)
+                                fprintf(f, "L:%i\n", udev_device_get_devlink_priority(udev_device));
+                        if (udev_device_get_watch_handle(udev_device) >= 0)
+                                fprintf(f, "W:%i\n", udev_device_get_watch_handle(udev_device));
+                }
+
+                if (udev_device_get_usec_initialized(udev_device) > 0)
+                        fprintf(f, "I:%llu\n", (unsigned long long)udev_device_get_usec_initialized(udev_device));
+
+                udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
+                        if (!udev_list_entry_get_num(list_entry))
+                                continue;
+                        fprintf(f, "E:%s=%s\n",
+                                udev_list_entry_get_name(list_entry),
+                                udev_list_entry_get_value(list_entry));
+                }
+
+                udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
+                        fprintf(f, "G:%s\n", udev_list_entry_get_name(list_entry));
+        }
+
+        fclose(f);
+        r = rename(filename_tmp, filename);
+        if (r < 0)
+                return -1;
+        udev_dbg(udev, "created %s file '%s' for '%s'\n", has_info ? "db" : "empty",
+             filename, udev_device_get_devpath(udev_device));
+        return 0;
+}
+
+int udev_device_delete_db(struct udev_device *udev_device)
+{
+        const char *id;
+        char filename[UTIL_PATH_SIZE];
+
+        id = udev_device_get_id_filename(udev_device);
+        if (id == NULL)
+                return -1;
+        util_strscpyl(filename, sizeof(filename), "/run/udev/data/", id, NULL);
+        unlink(filename);
+        return 0;
+}
diff --git a/src/libudev/libudev-device.c b/src/libudev/libudev-device.c
new file mode 100644
index 0000000000..acf8e24d15
--- /dev/null
+++ b/src/libudev/libudev-device.c
@@ -0,0 +1,1758 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <string.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <net/if.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <linux/sockios.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+/**
+ * SECTION:libudev-device
+ * @short_description: kernel sys devices
+ *
+ * Representation of kernel sys devices. Devices are uniquely identified
+ * by their syspath, every device has exactly one path in the kernel sys
+ * filesystem. Devices usually belong to a kernel subsystem, and and have
+ * a unique name inside that subsystem.
+ */
+
+/**
+ * udev_device:
+ *
+ * Opaque object representing one kernel sys device.
+ */
+struct udev_device {
+        struct udev *udev;
+        struct udev_device *parent_device;
+        char *syspath;
+        const char *devpath;
+        char *sysname;
+        const char *sysnum;
+        char *devnode;
+        mode_t devnode_mode;
+        char *subsystem;
+        char *devtype;
+        char *driver;
+        char *action;
+        char *devpath_old;
+        char *id_filename;
+        char **envp;
+        char *monitor_buf;
+        size_t monitor_buf_len;
+        struct udev_list devlinks_list;
+        struct udev_list properties_list;
+        struct udev_list sysattr_value_list;
+        struct udev_list sysattr_list;
+        struct udev_list tags_list;
+        unsigned long long int seqnum;
+        usec_t usec_initialized;
+        int devlink_priority;
+        int refcount;
+        dev_t devnum;
+        int ifindex;
+        int watch_handle;
+        int maj, min;
+        bool parent_set;
+        bool subsystem_set;
+        bool devtype_set;
+        bool devlinks_uptodate;
+        bool envp_uptodate;
+        bool tags_uptodate;
+        bool driver_set;
+        bool info_loaded;
+        bool db_loaded;
+        bool uevent_loaded;
+        bool is_initialized;
+        bool sysattr_list_read;
+        bool db_persist;
+};
+
+/**
+ * udev_device_get_seqnum:
+ * @udev_device: udev device
+ *
+ * This is only valid if the device was received through a monitor. Devices read from
+ * sys do not have a sequence number.
+ *
+ * Returns: the kernel event sequence number, or 0 if there is no sequence number available.
+ **/
+_public_ unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return 0;
+        return udev_device->seqnum;
+}
+
+static int udev_device_set_seqnum(struct udev_device *udev_device, unsigned long long int seqnum)
+{
+        char num[32];
+
+        udev_device->seqnum = seqnum;
+        snprintf(num, sizeof(num), "%llu", seqnum);
+        udev_device_add_property(udev_device, "SEQNUM", num);
+        return 0;
+}
+
+int udev_device_get_ifindex(struct udev_device *udev_device)
+{
+        if (!udev_device->info_loaded)
+                udev_device_read_uevent_file(udev_device);
+        return udev_device->ifindex;
+}
+
+static int udev_device_set_ifindex(struct udev_device *udev_device, int ifindex)
+{
+        char num[32];
+
+        udev_device->ifindex = ifindex;
+        snprintf(num, sizeof(num), "%u", ifindex);
+        udev_device_add_property(udev_device, "IFINDEX", num);
+        return 0;
+}
+
+/**
+ * udev_device_get_devnum:
+ * @udev_device: udev device
+ *
+ * Get the device major/minor number.
+ *
+ * Returns: the dev_t number.
+ **/
+_public_ dev_t udev_device_get_devnum(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return makedev(0, 0);
+        if (!udev_device->info_loaded)
+                udev_device_read_uevent_file(udev_device);
+        return udev_device->devnum;
+}
+
+static int udev_device_set_devnum(struct udev_device *udev_device, dev_t devnum)
+{
+        char num[32];
+
+        udev_device->devnum = devnum;
+
+        snprintf(num, sizeof(num), "%u", major(devnum));
+        udev_device_add_property(udev_device, "MAJOR", num);
+        snprintf(num, sizeof(num), "%u", minor(devnum));
+        udev_device_add_property(udev_device, "MINOR", num);
+        return 0;
+}
+
+const char *udev_device_get_devpath_old(struct udev_device *udev_device)
+{
+        return udev_device->devpath_old;
+}
+
+static int udev_device_set_devpath_old(struct udev_device *udev_device, const char *devpath_old)
+{
+        const char *pos;
+
+        free(udev_device->devpath_old);
+        udev_device->devpath_old = strdup(devpath_old);
+        if (udev_device->devpath_old == NULL)
+                return -ENOMEM;
+        udev_device_add_property(udev_device, "DEVPATH_OLD", udev_device->devpath_old);
+
+        pos = strrchr(udev_device->devpath_old, '/');
+        if (pos == NULL)
+                return -EINVAL;
+        return 0;
+}
+
+/**
+ * udev_device_get_driver:
+ * @udev_device: udev device
+ *
+ * Get the kernel driver name.
+ *
+ * Returns: the driver name string, or #NULL if there is no driver attached.
+ **/
+_public_ const char *udev_device_get_driver(struct udev_device *udev_device)
+{
+        char driver[UTIL_NAME_SIZE];
+
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->driver_set) {
+                udev_device->driver_set = true;
+                if (util_get_sys_core_link_value(udev_device->udev, "driver", udev_device->syspath, driver, sizeof(driver)) > 0)
+                        udev_device->driver = strdup(driver);
+        }
+        return udev_device->driver;
+}
+
+static int udev_device_set_driver(struct udev_device *udev_device, const char *driver)
+{
+        free(udev_device->driver);
+        udev_device->driver = strdup(driver);
+        if (udev_device->driver == NULL)
+                return -ENOMEM;
+        udev_device->driver_set = true;
+        udev_device_add_property(udev_device, "DRIVER", udev_device->driver);
+        return 0;
+}
+
+/**
+ * udev_device_get_devtype:
+ * @udev_device: udev device
+ *
+ * Retrieve the devtype string of the udev device.
+ *
+ * Returns: the devtype name of the udev device, or #NULL if it can not be determined
+ **/
+_public_ const char *udev_device_get_devtype(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->devtype_set) {
+                udev_device->devtype_set = true;
+                udev_device_read_uevent_file(udev_device);
+        }
+        return udev_device->devtype;
+}
+
+static int udev_device_set_devtype(struct udev_device *udev_device, const char *devtype)
+{
+        free(udev_device->devtype);
+        udev_device->devtype = strdup(devtype);
+        if (udev_device->devtype == NULL)
+                return -ENOMEM;
+        udev_device->devtype_set = true;
+        udev_device_add_property(udev_device, "DEVTYPE", udev_device->devtype);
+        return 0;
+}
+
+int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem)
+{
+        free(udev_device->subsystem);
+        udev_device->subsystem = strdup(subsystem);
+        if (udev_device->subsystem == NULL)
+                return -ENOMEM;
+        udev_device->subsystem_set = true;
+        udev_device_add_property(udev_device, "SUBSYSTEM", udev_device->subsystem);
+        return 0;
+}
+
+/**
+ * udev_device_get_subsystem:
+ * @udev_device: udev device
+ *
+ * Retrieve the subsystem string of the udev device. The string does not
+ * contain any "/".
+ *
+ * Returns: the subsystem name of the udev device, or #NULL if it can not be determined
+ **/
+_public_ const char *udev_device_get_subsystem(struct udev_device *udev_device)
+{
+        char subsystem[UTIL_NAME_SIZE];
+
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->subsystem_set) {
+                udev_device->subsystem_set = true;
+                /* read "subsystem" link */
+                if (util_get_sys_core_link_value(udev_device->udev, "subsystem", udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
+                        udev_device_set_subsystem(udev_device, subsystem);
+                        return udev_device->subsystem;
+                }
+                /* implicit names */
+                if (startswith(udev_device->devpath, "/module/")) {
+                        udev_device_set_subsystem(udev_device, "module");
+                        return udev_device->subsystem;
+                }
+                if (strstr(udev_device->devpath, "/drivers/") != NULL) {
+                        udev_device_set_subsystem(udev_device, "drivers");
+                        return udev_device->subsystem;
+                }
+                if (startswith(udev_device->devpath, "/subsystem/") ||
+                    startswith(udev_device->devpath, "/class/") ||
+                    startswith(udev_device->devpath, "/bus/")) {
+                        udev_device_set_subsystem(udev_device, "subsystem");
+                        return udev_device->subsystem;
+                }
+        }
+        return udev_device->subsystem;
+}
+
+mode_t udev_device_get_devnode_mode(struct udev_device *udev_device)
+{
+        if (!udev_device->info_loaded)
+                udev_device_read_uevent_file(udev_device);
+        return udev_device->devnode_mode;
+}
+
+static int udev_device_set_devnode_mode(struct udev_device *udev_device, mode_t mode)
+{
+        char num[32];
+
+        udev_device->devnode_mode = mode;
+        snprintf(num, sizeof(num), "%#o", mode);
+        udev_device_add_property(udev_device, "DEVMODE", num);
+        return 0;
+}
+
+struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
+{
+        udev_device->envp_uptodate = false;
+        if (value == NULL) {
+                struct udev_list_entry *list_entry;
+
+                list_entry = udev_device_get_properties_list_entry(udev_device);
+                list_entry = udev_list_entry_get_by_name(list_entry, key);
+                if (list_entry != NULL)
+                        udev_list_entry_delete(list_entry);
+                return NULL;
+        }
+        return udev_list_entry_add(&udev_device->properties_list, key, value);
+}
+
+static struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
+{
+        char name[UTIL_LINE_SIZE];
+        char *val;
+
+        util_strscpy(name, sizeof(name), property);
+        val = strchr(name, '=');
+        if (val == NULL)
+                return NULL;
+        val[0] = '\0';
+        val = &val[1];
+        if (val[0] == '\0')
+                val = NULL;
+        return udev_device_add_property(udev_device, name, val);
+}
+
+/*
+ * parse property string, and if needed, update internal values accordingly
+ *
+ * udev_device_add_property_from_string_parse_finish() needs to be
+ * called after adding properties, and its return value checked
+ *
+ * udev_device_set_info_loaded() needs to be set, to avoid trying
+ * to use a device without a DEVPATH set
+ */
+void udev_device_add_property_from_string_parse(struct udev_device *udev_device, const char *property)
+{
+        if (startswith(property, "DEVPATH=")) {
+                char path[UTIL_PATH_SIZE];
+
+                util_strscpyl(path, sizeof(path), "/sys", &property[8], NULL);
+                udev_device_set_syspath(udev_device, path);
+        } else if (startswith(property, "SUBSYSTEM=")) {
+                udev_device_set_subsystem(udev_device, &property[10]);
+        } else if (startswith(property, "DEVTYPE=")) {
+                udev_device_set_devtype(udev_device, &property[8]);
+        } else if (startswith(property, "DEVNAME=")) {
+                udev_device_set_devnode(udev_device, &property[8]);
+        } else if (startswith(property, "DEVLINKS=")) {
+                char devlinks[UTIL_PATH_SIZE];
+                char *slink;
+                char *next;
+
+                util_strscpy(devlinks, sizeof(devlinks), &property[9]);
+                slink = devlinks;
+                next = strchr(slink, ' ');
+                while (next != NULL) {
+                        next[0] = '\0';
+                        udev_device_add_devlink(udev_device, slink);
+                        slink = &next[1];
+                        next = strchr(slink, ' ');
+                }
+                if (slink[0] != '\0')
+                        udev_device_add_devlink(udev_device, slink);
+        } else if (startswith(property, "TAGS=")) {
+                char tags[UTIL_PATH_SIZE];
+                char *next;
+
+                util_strscpy(tags, sizeof(tags), &property[5]);
+                next = strchr(tags, ':');
+                if (next != NULL) {
+                        next++;
+                        while (next[0] != '\0') {
+                                char *tag;
+
+                                tag = next;
+                                next = strchr(tag, ':');
+                                if (next == NULL)
+                                        break;
+                                next[0] = '\0';
+                                next++;
+                                udev_device_add_tag(udev_device, tag);
+                        }
+                }
+        } else if (startswith(property, "USEC_INITIALIZED=")) {
+                udev_device_set_usec_initialized(udev_device, strtoull(&property[19], NULL, 10));
+        } else if (startswith(property, "DRIVER=")) {
+                udev_device_set_driver(udev_device, &property[7]);
+        } else if (startswith(property, "ACTION=")) {
+                udev_device_set_action(udev_device, &property[7]);
+        } else if (startswith(property, "MAJOR=")) {
+                udev_device->maj = strtoull(&property[6], NULL, 10);
+        } else if (startswith(property, "MINOR=")) {
+                udev_device->min = strtoull(&property[6], NULL, 10);
+        } else if (startswith(property, "DEVPATH_OLD=")) {
+                udev_device_set_devpath_old(udev_device, &property[12]);
+        } else if (startswith(property, "SEQNUM=")) {
+                udev_device_set_seqnum(udev_device, strtoull(&property[7], NULL, 10));
+        } else if (startswith(property, "IFINDEX=")) {
+                udev_device_set_ifindex(udev_device, strtoull(&property[8], NULL, 10));
+        } else if (startswith(property, "DEVMODE=")) {
+                udev_device_set_devnode_mode(udev_device, strtoul(&property[8], NULL, 8));
+        } else {
+                udev_device_add_property_from_string(udev_device, property);
+        }
+}
+
+int udev_device_add_property_from_string_parse_finish(struct udev_device *udev_device)
+{
+        if (udev_device->maj > 0)
+                udev_device_set_devnum(udev_device, makedev(udev_device->maj, udev_device->min));
+        udev_device->maj = 0;
+        udev_device->min = 0;
+
+        if (udev_device->devpath == NULL || udev_device->subsystem == NULL)
+                return -EINVAL;
+        return 0;
+}
+
+/**
+ * udev_device_get_property_value:
+ * @udev_device: udev device
+ * @key: property name
+ *
+ * Get the value of a given property.
+ *
+ * Returns: the property string, or #NULL if there is no such property.
+ **/
+_public_ const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key)
+{
+        struct udev_list_entry *list_entry;
+
+        if (udev_device == NULL)
+                return NULL;
+        if (key == NULL)
+                return NULL;
+
+        list_entry = udev_device_get_properties_list_entry(udev_device);
+        list_entry = udev_list_entry_get_by_name(list_entry, key);
+        return udev_list_entry_get_value(list_entry);
+}
+
+int udev_device_read_db(struct udev_device *udev_device, const char *dbfile)
+{
+        char filename[UTIL_PATH_SIZE];
+        char line[UTIL_LINE_SIZE];
+        FILE *f;
+
+        /* providing a database file will always force-load it */
+        if (dbfile == NULL) {
+                const char *id;
+
+                if (udev_device->db_loaded)
+                        return 0;
+                udev_device->db_loaded = true;
+
+                id = udev_device_get_id_filename(udev_device);
+                if (id == NULL)
+                        return -1;
+                util_strscpyl(filename, sizeof(filename), "/run/udev/data/", id, NULL);
+                dbfile = filename;
+        }
+
+        f = fopen(dbfile, "re");
+        if (f == NULL) {
+                udev_dbg(udev_device->udev, "no db file to read %s: %m\n", dbfile);
+                return -1;
+        }
+        udev_device->is_initialized = true;
+
+        while (fgets(line, sizeof(line), f)) {
+                ssize_t len;
+                const char *val;
+                struct udev_list_entry *entry;
+
+                len = strlen(line);
+                if (len < 4)
+                        break;
+                line[len-1] = '\0';
+                val = &line[2];
+                switch(line[0]) {
+                case 'S':
+                        util_strscpyl(filename, sizeof(filename), "/dev/", val, NULL);
+                        udev_device_add_devlink(udev_device, filename);
+                        break;
+                case 'L':
+                        udev_device_set_devlink_priority(udev_device, atoi(val));
+                        break;
+                case 'E':
+                        entry = udev_device_add_property_from_string(udev_device, val);
+                        udev_list_entry_set_num(entry, true);
+                        break;
+                case 'G':
+                        udev_device_add_tag(udev_device, val);
+                        break;
+                case 'W':
+                        udev_device_set_watch_handle(udev_device, atoi(val));
+                        break;
+                case 'I':
+                        udev_device_set_usec_initialized(udev_device, strtoull(val, NULL, 10));
+                        break;
+                }
+        }
+        fclose(f);
+
+        udev_dbg(udev_device->udev, "device %p filled with db file data\n", udev_device);
+        return 0;
+}
+
+int udev_device_read_uevent_file(struct udev_device *udev_device)
+{
+        char filename[UTIL_PATH_SIZE];
+        FILE *f;
+        char line[UTIL_LINE_SIZE];
+        int maj = 0;
+        int min = 0;
+
+        if (udev_device->uevent_loaded)
+                return 0;
+
+        util_strscpyl(filename, sizeof(filename), udev_device->syspath, "/uevent", NULL);
+        f = fopen(filename, "re");
+        if (f == NULL)
+                return -1;
+        udev_device->uevent_loaded = true;
+
+        while (fgets(line, sizeof(line), f)) {
+                char *pos;
+
+                pos = strchr(line, '\n');
+                if (pos == NULL)
+                        continue;
+                pos[0] = '\0';
+
+                if (startswith(line, "DEVTYPE=")) {
+                        udev_device_set_devtype(udev_device, &line[8]);
+                        continue;
+                }
+                if (startswith(line, "IFINDEX=")) {
+                        udev_device_set_ifindex(udev_device, strtoull(&line[8], NULL, 10));
+                        continue;
+                }
+                if (startswith(line, "DEVNAME=")) {
+                        udev_device_set_devnode(udev_device, &line[8]);
+                        continue;
+                }
+
+                if (startswith(line, "MAJOR="))
+                        maj = strtoull(&line[6], NULL, 10);
+                else if (startswith(line, "MINOR="))
+                        min = strtoull(&line[6], NULL, 10);
+                else if (startswith(line, "DEVMODE="))
+                        udev_device->devnode_mode = strtoul(&line[8], NULL, 8);
+
+                udev_device_add_property_from_string(udev_device, line);
+        }
+
+        udev_device->devnum = makedev(maj, min);
+        fclose(f);
+        return 0;
+}
+
+void udev_device_set_info_loaded(struct udev_device *device)
+{
+        device->info_loaded = true;
+}
+
+struct udev_device *udev_device_new(struct udev *udev)
+{
+        struct udev_device *udev_device;
+        struct udev_list_entry *list_entry;
+
+        if (udev == NULL)
+                return NULL;
+
+        udev_device = calloc(1, sizeof(struct udev_device));
+        if (udev_device == NULL)
+                return NULL;
+        udev_device->refcount = 1;
+        udev_device->udev = udev;
+        udev_list_init(udev, &udev_device->devlinks_list, true);
+        udev_list_init(udev, &udev_device->properties_list, true);
+        udev_list_init(udev, &udev_device->sysattr_value_list, true);
+        udev_list_init(udev, &udev_device->sysattr_list, false);
+        udev_list_init(udev, &udev_device->tags_list, true);
+        udev_device->watch_handle = -1;
+        /* copy global properties */
+        udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
+                udev_device_add_property(udev_device,
+                                         udev_list_entry_get_name(list_entry),
+                                         udev_list_entry_get_value(list_entry));
+        return udev_device;
+}
+
+/**
+ * udev_device_new_from_syspath:
+ * @udev: udev library context
+ * @syspath: sys device path including sys directory
+ *
+ * Create new udev device, and fill in information from the sys
+ * device and the udev database entry. The syspath is the absolute
+ * path to the device, including the sys mount point.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
+_public_ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
+{
+        const char *subdir;
+        char path[UTIL_PATH_SIZE];
+        char *pos;
+        struct stat statbuf;
+        struct udev_device *udev_device;
+
+        if (udev == NULL)
+                return NULL;
+        if (syspath == NULL)
+                return NULL;
+
+        /* path starts in sys */
+        if (!startswith(syspath, "/sys")) {
+                udev_dbg(udev, "not in sys :%s\n", syspath);
+                return NULL;
+        }
+
+        /* path is not a root directory */
+        subdir = syspath + strlen("/sys");
+        pos = strrchr(subdir, '/');
+        if (pos == NULL || pos[1] == '\0' || pos < &subdir[2])
+                return NULL;
+
+        /* resolve possible symlink to real path */
+        util_strscpy(path, sizeof(path), syspath);
+        util_resolve_sys_link(udev, path, sizeof(path));
+
+        if (startswith(path + strlen("/sys"), "/devices/")) {
+                char file[UTIL_PATH_SIZE];
+
+                /* all "devices" require a "uevent" file */
+                util_strscpyl(file, sizeof(file), path, "/uevent", NULL);
+                if (stat(file, &statbuf) != 0)
+                        return NULL;
+        } else {
+                /* everything else just needs to be a directory */
+                if (stat(path, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode))
+                        return NULL;
+        }
+
+        udev_device = udev_device_new(udev);
+        if (udev_device == NULL)
+                return NULL;
+
+        udev_device_set_syspath(udev_device, path);
+        udev_dbg(udev, "device %p has devpath '%s'\n", udev_device, udev_device_get_devpath(udev_device));
+
+        return udev_device;
+}
+
+/**
+ * udev_device_new_from_devnum:
+ * @udev: udev library context
+ * @type: char or block device
+ * @devnum: device major/minor number
+ *
+ * Create new udev device, and fill in information from the sys
+ * device and the udev database entry. The device is looked-up
+ * by its major/minor number and type. Character and block device
+ * numbers are not unique across the two types.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
+_public_ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
+{
+        char path[UTIL_PATH_SIZE];
+        const char *type_str;
+
+        if (type == 'b')
+                type_str = "block";
+        else if (type == 'c')
+                type_str = "char";
+        else
+                return NULL;
+
+        /* use /sys/dev/{block,char}/<maj>:<min> link */
+        snprintf(path, sizeof(path), "/sys/dev/%s/%u:%u",
+                 type_str, major(devnum), minor(devnum));
+        return udev_device_new_from_syspath(udev, path);
+}
+
+/**
+ * udev_device_new_from_device_id:
+ * @udev: udev library context
+ * @id: text string identifying a kernel device
+ *
+ * Create new udev device, and fill in information from the sys
+ * device and the udev database entry. The device is looked-up
+ * by a special string:
+ *   b8:2          - block device major:minor
+ *   c128:1        - char device major:minor
+ *   n3            - network device ifindex
+ *   +sound:card29 - kernel driver core subsystem:device name
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
+_public_ struct udev_device *udev_device_new_from_device_id(struct udev *udev, char *id)
+{
+        char type;
+        int maj, min;
+        char subsys[UTIL_PATH_SIZE];
+        char *sysname;
+
+        switch(id[0]) {
+        case 'b':
+        case 'c':
+                if (sscanf(id, "%c%i:%i", &type, &maj, &min) != 3)
+                        return NULL;
+                return udev_device_new_from_devnum(udev, type, makedev(maj, min));
+        case 'n': {
+                int sk;
+                struct ifreq ifr;
+                struct udev_device *dev;
+                int ifindex;
+
+                ifindex = strtoul(&id[1], NULL, 10);
+                if (ifindex <= 0)
+                        return NULL;
+
+                sk = socket(PF_INET, SOCK_DGRAM, 0);
+                if (sk < 0)
+                        return NULL;
+                memset(&ifr, 0x00, sizeof(struct ifreq));
+                ifr.ifr_ifindex = ifindex;
+                if (ioctl(sk, SIOCGIFNAME, &ifr) != 0) {
+                        close(sk);
+                        return NULL;
+                }
+                close(sk);
+
+                dev = udev_device_new_from_subsystem_sysname(udev, "net", ifr.ifr_name);
+                if (dev == NULL)
+                        return NULL;
+                if (udev_device_get_ifindex(dev) == ifindex)
+                        return dev;
+                udev_device_unref(dev);
+                return NULL;
+        }
+        case '+':
+                util_strscpy(subsys, sizeof(subsys), &id[1]);
+                sysname = strchr(subsys, ':');
+                if (sysname == NULL)
+                        return NULL;
+                sysname[0] = '\0';
+                sysname = &sysname[1];
+                return udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
+        default:
+                return NULL;
+        }
+}
+
+/**
+ * udev_device_new_from_subsystem_sysname:
+ * @udev: udev library context
+ * @subsystem: the subsystem of the device
+ * @sysname: the name of the device
+ *
+ * Create new udev device, and fill in information from the sys device
+ * and the udev database entry. The device is looked up by the subsystem
+ * and name string of the device, like "mem" / "zero", or "block" / "sda".
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
+_public_ struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
+{
+        char path[UTIL_PATH_SIZE];
+        struct stat statbuf;
+
+        if (streq(subsystem, "subsystem")) {
+                util_strscpyl(path, sizeof(path), "/sys/subsystem/", sysname, NULL);
+                if (stat(path, &statbuf) == 0)
+                        goto found;
+
+                util_strscpyl(path, sizeof(path), "/sys/bus/", sysname, NULL);
+                if (stat(path, &statbuf) == 0)
+                        goto found;
+
+                util_strscpyl(path, sizeof(path), "/sys/class/", sysname, NULL);
+                if (stat(path, &statbuf) == 0)
+                        goto found;
+                goto out;
+        }
+
+        if (streq(subsystem, "module")) {
+                util_strscpyl(path, sizeof(path), "/sys/module/", sysname, NULL);
+                if (stat(path, &statbuf) == 0)
+                        goto found;
+                goto out;
+        }
+
+        if (streq(subsystem, "drivers")) {
+                char subsys[UTIL_NAME_SIZE];
+                char *driver;
+
+                util_strscpy(subsys, sizeof(subsys), sysname);
+                driver = strchr(subsys, ':');
+                if (driver != NULL) {
+                        driver[0] = '\0';
+                        driver = &driver[1];
+
+                        util_strscpyl(path, sizeof(path), "/sys/subsystem/", subsys, "/drivers/", driver, NULL);
+                        if (stat(path, &statbuf) == 0)
+                                goto found;
+
+                        util_strscpyl(path, sizeof(path), "/sys/bus/", subsys, "/drivers/", driver, NULL);
+                        if (stat(path, &statbuf) == 0)
+                                goto found;
+                }
+                goto out;
+        }
+
+        util_strscpyl(path, sizeof(path), "/sys/subsystem/", subsystem, "/devices/", sysname, NULL);
+        if (stat(path, &statbuf) == 0)
+                goto found;
+
+        util_strscpyl(path, sizeof(path), "/sys/bus/", subsystem, "/devices/", sysname, NULL);
+        if (stat(path, &statbuf) == 0)
+                goto found;
+
+        util_strscpyl(path, sizeof(path), "/sys/class/", subsystem, "/", sysname, NULL);
+        if (stat(path, &statbuf) == 0)
+                goto found;
+out:
+        return NULL;
+found:
+        return udev_device_new_from_syspath(udev, path);
+}
+
+/**
+ * udev_device_new_from_environment
+ * @udev: udev library context
+ *
+ * Create new udev device, and fill in information from the
+ * current process environment. This only works reliable if
+ * the process is called from a udev rule. It is usually used
+ * for tools executed from IMPORT= rules.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
+_public_ struct udev_device *udev_device_new_from_environment(struct udev *udev)
+{
+        int i;
+        struct udev_device *udev_device;
+
+        udev_device = udev_device_new(udev);
+        if (udev_device == NULL)
+                return NULL;
+        udev_device_set_info_loaded(udev_device);
+
+        for (i = 0; environ[i] != NULL; i++)
+                udev_device_add_property_from_string_parse(udev_device, environ[i]);
+
+        if (udev_device_add_property_from_string_parse_finish(udev_device) < 0) {
+                udev_dbg(udev, "missing values, invalid device\n");
+                udev_device_unref(udev_device);
+                udev_device = NULL;
+        }
+
+        return udev_device;
+}
+
+static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
+{
+        struct udev_device *udev_device_parent = NULL;
+        char path[UTIL_PATH_SIZE];
+        const char *subdir;
+
+        util_strscpy(path, sizeof(path), udev_device->syspath);
+        subdir = path + strlen("/sys/");
+        for (;;) {
+                char *pos;
+
+                pos = strrchr(subdir, '/');
+                if (pos == NULL || pos < &subdir[2])
+                        break;
+                pos[0] = '\0';
+                udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
+                if (udev_device_parent != NULL)
+                        return udev_device_parent;
+        }
+        return NULL;
+}
+
+/**
+ * udev_device_get_parent:
+ * @udev_device: the device to start searching from
+ *
+ * Find the next parent device, and fill in information from the sys
+ * device and the udev database entry.
+ *
+ * The returned the device is not referenced. It is attached to the
+ * child device, and will be cleaned up when the child device
+ * is cleaned up.
+ *
+ * It is not necessarily just the upper level directory, empty or not
+ * recognized sys directories are ignored.
+ *
+ * It can be called as many times as needed, without caring about
+ * references.
+ *
+ * Returns: a new udev device, or #NULL, if it no parent exist.
+ **/
+_public_ struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->parent_set) {
+                udev_device->parent_set = true;
+                udev_device->parent_device = device_new_from_parent(udev_device);
+        }
+        return udev_device->parent_device;
+}
+
+/**
+ * udev_device_get_parent_with_subsystem_devtype:
+ * @udev_device: udev device to start searching from
+ * @subsystem: the subsystem of the device
+ * @devtype: the type (DEVTYPE) of the device
+ *
+ * Find the next parent device, with a matching subsystem and devtype
+ * value, and fill in information from the sys device and the udev
+ * database entry.
+ *
+ * If devtype is #NULL, only subsystem is checked, and any devtype will
+ * match.
+ *
+ * The returned the device is not referenced. It is attached to the
+ * child device, and will be cleaned up when the child device
+ * is cleaned up.
+ *
+ * It can be called as many times as needed, without caring about
+ * references.
+ *
+ * Returns: a new udev device, or #NULL if no matching parent exists.
+ **/
+_public_ struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device, const char *subsystem, const char *devtype)
+{
+        struct udev_device *parent;
+
+        if (subsystem == NULL)
+                return NULL;
+
+        parent = udev_device_get_parent(udev_device);
+        while (parent != NULL) {
+                const char *parent_subsystem;
+                const char *parent_devtype;
+
+                parent_subsystem = udev_device_get_subsystem(parent);
+                if (parent_subsystem != NULL && streq(parent_subsystem, subsystem)) {
+                        if (devtype == NULL)
+                                break;
+                        parent_devtype = udev_device_get_devtype(parent);
+                        if (parent_devtype != NULL && streq(parent_devtype, devtype))
+                                break;
+                }
+                parent = udev_device_get_parent(parent);
+        }
+        return parent;
+}
+
+/**
+ * udev_device_get_udev:
+ * @udev_device: udev device
+ *
+ * Retrieve the udev library context the device was created with.
+ *
+ * Returns: the udev library context
+ **/
+_public_ struct udev *udev_device_get_udev(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        return udev_device->udev;
+}
+
+/**
+ * udev_device_ref:
+ * @udev_device: udev device
+ *
+ * Take a reference of a udev device.
+ *
+ * Returns: the passed udev device
+ **/
+_public_ struct udev_device *udev_device_ref(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        udev_device->refcount++;
+        return udev_device;
+}
+
+/**
+ * udev_device_unref:
+ * @udev_device: udev device
+ *
+ * Drop a reference of a udev device. If the refcount reaches zero,
+ * the resources of the device will be released.
+ *
+ * Returns: the passed udev device if it has still an active reference, or #NULL otherwise.
+ **/
+_public_ struct udev_device *udev_device_unref(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        udev_device->refcount--;
+        if (udev_device->refcount > 0)
+                return udev_device;
+        if (udev_device->parent_device != NULL)
+                udev_device_unref(udev_device->parent_device);
+        free(udev_device->syspath);
+        free(udev_device->sysname);
+        free(udev_device->devnode);
+        free(udev_device->subsystem);
+        free(udev_device->devtype);
+        udev_list_cleanup(&udev_device->devlinks_list);
+        udev_list_cleanup(&udev_device->properties_list);
+        udev_list_cleanup(&udev_device->sysattr_value_list);
+        udev_list_cleanup(&udev_device->sysattr_list);
+        udev_list_cleanup(&udev_device->tags_list);
+        free(udev_device->action);
+        free(udev_device->driver);
+        free(udev_device->devpath_old);
+        free(udev_device->id_filename);
+        free(udev_device->envp);
+        free(udev_device->monitor_buf);
+        free(udev_device);
+        return NULL;
+}
+
+/**
+ * udev_device_get_devpath:
+ * @udev_device: udev device
+ *
+ * Retrieve the kernel devpath value of the udev device. The path
+ * does not contain the sys mount point, and starts with a '/'.
+ *
+ * Returns: the devpath of the udev device
+ **/
+_public_ const char *udev_device_get_devpath(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        return udev_device->devpath;
+}
+
+/**
+ * udev_device_get_syspath:
+ * @udev_device: udev device
+ *
+ * Retrieve the sys path of the udev device. The path is an
+ * absolute path and starts with the sys mount point.
+ *
+ * Returns: the sys path of the udev device
+ **/
+_public_ const char *udev_device_get_syspath(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        return udev_device->syspath;
+}
+
+/**
+ * udev_device_get_sysname:
+ * @udev_device: udev device
+ *
+ * Get the kernel device name in /sys.
+ *
+ * Returns: the name string of the device device
+ **/
+_public_ const char *udev_device_get_sysname(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        return udev_device->sysname;
+}
+
+/**
+ * udev_device_get_sysnum:
+ * @udev_device: udev device
+ *
+ * Get the instance number of the device.
+ *
+ * Returns: the trailing number string of the device name
+ **/
+_public_ const char *udev_device_get_sysnum(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        return udev_device->sysnum;
+}
+
+/**
+ * udev_device_get_devnode:
+ * @udev_device: udev device
+ *
+ * Retrieve the device node file name belonging to the udev device.
+ * The path is an absolute path, and starts with the device directory.
+ *
+ * Returns: the device node file name of the udev device, or #NULL if no device node exists
+ **/
+_public_ const char *udev_device_get_devnode(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        if (udev_device->devnode != NULL)
+                return udev_device->devnode;
+        if (!udev_device->info_loaded)
+                udev_device_read_uevent_file(udev_device);
+        return udev_device->devnode;
+}
+
+/**
+ * udev_device_get_devlinks_list_entry:
+ * @udev_device: udev device
+ *
+ * Retrieve the list of device links pointing to the device file of
+ * the udev device. The next list entry can be retrieved with
+ * udev_list_entry_get_next(), which returns #NULL if no more entries exist.
+ * The devlink path can be retrieved from the list entry by
+ * udev_list_entry_get_name(). The path is an absolute path, and starts with
+ * the device directory.
+ *
+ * Returns: the first entry of the device node link list
+ **/
+_public_ struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        return udev_list_get_entry(&udev_device->devlinks_list);
+}
+
+void udev_device_cleanup_devlinks_list(struct udev_device *udev_device)
+{
+        udev_device->devlinks_uptodate = false;
+        udev_list_cleanup(&udev_device->devlinks_list);
+}
+
+/**
+ * udev_device_get_properties_list_entry:
+ * @udev_device: udev device
+ *
+ * Retrieve the list of key/value device properties of the udev
+ * device. The next list entry can be retrieved with udev_list_entry_get_next(),
+ * which returns #NULL if no more entries exist. The property name
+ * can be retrieved from the list entry by udev_list_entry_get_name(),
+ * the property value by udev_list_entry_get_value().
+ *
+ * Returns: the first entry of the property list
+ **/
+_public_ struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->info_loaded) {
+                udev_device_read_uevent_file(udev_device);
+                udev_device_read_db(udev_device, NULL);
+        }
+        if (!udev_device->devlinks_uptodate) {
+                char symlinks[UTIL_PATH_SIZE];
+                struct udev_list_entry *list_entry;
+
+                udev_device->devlinks_uptodate = true;
+                list_entry = udev_device_get_devlinks_list_entry(udev_device);
+                if (list_entry != NULL) {
+                        char *s;
+                        size_t l;
+
+                        s = symlinks;
+                        l = util_strpcpyl(&s, sizeof(symlinks), udev_list_entry_get_name(list_entry), NULL);
+                        udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
+                                l = util_strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry), NULL);
+                        udev_device_add_property(udev_device, "DEVLINKS", symlinks);
+                }
+        }
+        if (!udev_device->tags_uptodate) {
+                udev_device->tags_uptodate = true;
+                if (udev_device_get_tags_list_entry(udev_device) != NULL) {
+                        char tags[UTIL_PATH_SIZE];
+                        struct udev_list_entry *list_entry;
+                        char *s;
+                        size_t l;
+
+                        s = tags;
+                        l = util_strpcpyl(&s, sizeof(tags), ":", NULL);
+                        udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
+                                l = util_strpcpyl(&s, l, udev_list_entry_get_name(list_entry), ":", NULL);
+                        udev_device_add_property(udev_device, "TAGS", tags);
+                }
+        }
+        return udev_list_get_entry(&udev_device->properties_list);
+}
+
+/**
+ * udev_device_get_action:
+ * @udev_device: udev device
+ *
+ * This is only valid if the device was received through a monitor. Devices read from
+ * sys do not have an action string. Usual actions are: add, remove, change, online,
+ * offline.
+ *
+ * Returns: the kernel action value, or #NULL if there is no action value available.
+ **/
+_public_ const char *udev_device_get_action(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        return udev_device->action;
+}
+
+/**
+ * udev_device_get_usec_since_initialized:
+ * @udev_device: udev device
+ *
+ * Return the number of microseconds passed since udev set up the
+ * device for the first time.
+ *
+ * This is only implemented for devices with need to store properties
+ * in the udev database. All other devices return 0 here.
+ *
+ * Returns: the number of microseconds since the device was first seen.
+ **/
+_public_ unsigned long long int udev_device_get_usec_since_initialized(struct udev_device *udev_device)
+{
+        usec_t now_ts;
+
+        if (udev_device == NULL)
+                return 0;
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        if (udev_device->usec_initialized == 0)
+                return 0;
+        now_ts = now(CLOCK_MONOTONIC);
+        if (now_ts == 0)
+                return 0;
+        return now_ts - udev_device->usec_initialized;
+}
+
+usec_t udev_device_get_usec_initialized(struct udev_device *udev_device)
+{
+        return udev_device->usec_initialized;
+}
+
+void udev_device_set_usec_initialized(struct udev_device *udev_device, usec_t usec_initialized)
+{
+        char num[32];
+
+        udev_device->usec_initialized = usec_initialized;
+        snprintf(num, sizeof(num), "%llu", (unsigned long long)usec_initialized);
+        udev_device_add_property(udev_device, "USEC_INITIALIZED", num);
+}
+
+/**
+ * udev_device_get_sysattr_value:
+ * @udev_device: udev device
+ * @sysattr: attribute name
+ *
+ * The retrieved value is cached in the device. Repeated calls will return the same
+ * value and not open the attribute again.
+ *
+ * Returns: the content of a sys attribute file, or #NULL if there is no sys attribute value.
+ **/
+_public_ const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
+{
+        struct udev_list_entry *list_entry;
+        char path[UTIL_PATH_SIZE];
+        char value[4096];
+        struct stat statbuf;
+        int fd;
+        ssize_t size;
+        const char *val = NULL;
+
+        if (udev_device == NULL)
+                return NULL;
+        if (sysattr == NULL)
+                return NULL;
+
+        /* look for possibly already cached result */
+        list_entry = udev_list_get_entry(&udev_device->sysattr_value_list);
+        list_entry = udev_list_entry_get_by_name(list_entry, sysattr);
+        if (list_entry != NULL)
+                return udev_list_entry_get_value(list_entry);
+
+        util_strscpyl(path, sizeof(path), udev_device_get_syspath(udev_device), "/", sysattr, NULL);
+        if (lstat(path, &statbuf) != 0) {
+                udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, NULL);
+                goto out;
+        }
+
+        if (S_ISLNK(statbuf.st_mode)) {
+                struct udev_device *dev;
+
+                /*
+                 * Some core links return only the last element of the target path,
+                 * these are just values, the paths should not be exposed.
+                 */
+                if (streq(sysattr, "driver") ||
+                    streq(sysattr, "subsystem") ||
+                    streq(sysattr, "module")) {
+                        if (util_get_sys_core_link_value(udev_device->udev, sysattr,
+                                                         udev_device->syspath, value, sizeof(value)) < 0)
+                                return NULL;
+                        list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, value);
+                        val = udev_list_entry_get_value(list_entry);
+                        goto out;
+                }
+
+                /* resolve link to a device and return its syspath */
+                util_strscpyl(path, sizeof(path), udev_device->syspath, "/", sysattr, NULL);
+                dev = udev_device_new_from_syspath(udev_device->udev, path);
+                if (dev != NULL) {
+                        list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr,
+                                                         udev_device_get_syspath(dev));
+                        val = udev_list_entry_get_value(list_entry);
+                        udev_device_unref(dev);
+                }
+
+                goto out;
+        }
+
+        /* skip directories */
+        if (S_ISDIR(statbuf.st_mode))
+                goto out;
+
+        /* skip non-readable files */
+        if ((statbuf.st_mode & S_IRUSR) == 0)
+                goto out;
+
+        /* read attribute value */
+        fd = open(path, O_RDONLY|O_CLOEXEC);
+        if (fd < 0)
+                goto out;
+        size = read(fd, value, sizeof(value));
+        close(fd);
+        if (size < 0)
+                goto out;
+        if (size == sizeof(value))
+                goto out;
+
+        /* got a valid value, store it in cache and return it */
+        value[size] = '\0';
+        util_remove_trailing_chars(value, '\n');
+        list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, value);
+        val = udev_list_entry_get_value(list_entry);
+out:
+        return val;
+}
+
+static int udev_device_sysattr_list_read(struct udev_device *udev_device)
+{
+        struct dirent *dent;
+        DIR *dir;
+        int num = 0;
+
+        if (udev_device == NULL)
+                return -1;
+        if (udev_device->sysattr_list_read)
+                return 0;
+
+        dir = opendir(udev_device_get_syspath(udev_device));
+        if (!dir)
+                return -1;
+
+        for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                char path[UTIL_PATH_SIZE];
+                struct stat statbuf;
+
+                /* only handle symlinks and regular files */
+                if (dent->d_type != DT_LNK && dent->d_type != DT_REG)
+                        continue;
+
+                util_strscpyl(path, sizeof(path), udev_device_get_syspath(udev_device), "/", dent->d_name, NULL);
+                if (lstat(path, &statbuf) != 0)
+                        continue;
+                if ((statbuf.st_mode & S_IRUSR) == 0)
+                        continue;
+
+                udev_list_entry_add(&udev_device->sysattr_list, dent->d_name, NULL);
+                num++;
+        }
+
+        closedir(dir);
+        udev_device->sysattr_list_read = true;
+
+        return num;
+}
+
+/**
+ * udev_device_get_sysattr_list_entry:
+ * @udev_device: udev device
+ *
+ * Retrieve the list of available sysattrs, with value being empty;
+ * This just return all available sysfs attributes for a particular
+ * device without reading their values.
+ *
+ * Returns: the first entry of the property list
+ **/
+_public_ struct udev_list_entry *udev_device_get_sysattr_list_entry(struct udev_device *udev_device)
+{
+        if (!udev_device->sysattr_list_read) {
+                int ret;
+                ret = udev_device_sysattr_list_read(udev_device);
+                if (0 > ret)
+                        return NULL;
+        }
+
+        return udev_list_get_entry(&udev_device->sysattr_list);
+}
+
+int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath)
+{
+        const char *pos;
+        size_t len;
+
+        free(udev_device->syspath);
+        udev_device->syspath = strdup(syspath);
+        if (udev_device->syspath ==  NULL)
+                return -ENOMEM;
+        udev_device->devpath = udev_device->syspath + strlen("/sys");
+        udev_device_add_property(udev_device, "DEVPATH", udev_device->devpath);
+
+        pos = strrchr(udev_device->syspath, '/');
+        if (pos == NULL)
+                return -EINVAL;
+        udev_device->sysname = strdup(&pos[1]);
+        if (udev_device->sysname == NULL)
+                return -ENOMEM;
+
+        /* some devices have '!' in their name, change that to '/' */
+        len = 0;
+        while (udev_device->sysname[len] != '\0') {
+                if (udev_device->sysname[len] == '!')
+                        udev_device->sysname[len] = '/';
+                len++;
+        }
+
+        /* trailing number */
+        while (len > 0 && isdigit(udev_device->sysname[--len]))
+                udev_device->sysnum = &udev_device->sysname[len];
+
+        /* sysname is completely numeric */
+        if (len == 0)
+                udev_device->sysnum = NULL;
+
+        return 0;
+}
+
+int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode)
+{
+        free(udev_device->devnode);
+        if (devnode[0] != '/') {
+                if (asprintf(&udev_device->devnode, "/dev/%s", devnode) < 0)
+                        udev_device->devnode = NULL;
+        } else {
+                udev_device->devnode = strdup(devnode);
+        }
+        if (udev_device->devnode == NULL)
+                return -ENOMEM;
+        udev_device_add_property(udev_device, "DEVNAME", udev_device->devnode);
+        return 0;
+}
+
+int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink)
+{
+        struct udev_list_entry *list_entry;
+
+        udev_device->devlinks_uptodate = false;
+        list_entry = udev_list_entry_add(&udev_device->devlinks_list, devlink, NULL);
+        if (list_entry == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+const char *udev_device_get_id_filename(struct udev_device *udev_device)
+{
+        if (udev_device->id_filename == NULL) {
+                if (udev_device_get_subsystem(udev_device) == NULL)
+                        return NULL;
+
+                if (major(udev_device_get_devnum(udev_device)) > 0) {
+                        /* use dev_t -- b259:131072, c254:0 */
+                        if (asprintf(&udev_device->id_filename, "%c%u:%u",
+                                     streq(udev_device_get_subsystem(udev_device), "block") ? 'b' : 'c',
+                                     major(udev_device_get_devnum(udev_device)),
+                                     minor(udev_device_get_devnum(udev_device))) < 0)
+                                udev_device->id_filename = NULL;
+                } else if (udev_device_get_ifindex(udev_device) > 0) {
+                        /* use netdev ifindex -- n3 */
+                        if (asprintf(&udev_device->id_filename, "n%u", udev_device_get_ifindex(udev_device)) < 0)
+                                udev_device->id_filename = NULL;
+                } else {
+                        /*
+                         * use $subsys:$syname -- pci:0000:00:1f.2
+                         * sysname() has '!' translated, get it from devpath
+                         */
+                        const char *sysname;
+                        sysname = strrchr(udev_device->devpath, '/');
+                        if (sysname == NULL)
+                                return NULL;
+                        sysname = &sysname[1];
+                        if (asprintf(&udev_device->id_filename, "+%s:%s", udev_device_get_subsystem(udev_device), sysname) < 0)
+                                udev_device->id_filename = NULL;
+                }
+        }
+        return udev_device->id_filename;
+}
+
+/**
+ * udev_device_get_is_initialized:
+ * @udev_device: udev device
+ *
+ * Check if udev has already handled the device and has set up
+ * device node permissions and context, or has renamed a network
+ * device.
+ *
+ * This is only implemented for devices with a device node
+ * or network interfaces. All other devices return 1 here.
+ *
+ * Returns: 1 if the device is set up. 0 otherwise.
+ **/
+_public_ int udev_device_get_is_initialized(struct udev_device *udev_device)
+{
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        return udev_device->is_initialized;
+}
+
+void udev_device_set_is_initialized(struct udev_device *udev_device)
+{
+        udev_device->is_initialized = true;
+}
+
+int udev_device_add_tag(struct udev_device *udev_device, const char *tag)
+{
+        if (strchr(tag, ':') != NULL || strchr(tag, ' ') != NULL)
+                return -EINVAL;
+        udev_device->tags_uptodate = false;
+        if (udev_list_entry_add(&udev_device->tags_list, tag, NULL) != NULL)
+                return 0;
+        return -ENOMEM;
+}
+
+void udev_device_cleanup_tags_list(struct udev_device *udev_device)
+{
+        udev_device->tags_uptodate = false;
+        udev_list_cleanup(&udev_device->tags_list);
+}
+
+/**
+ * udev_device_get_tags_list_entry:
+ * @udev_device: udev device
+ *
+ * Retrieve the list of tags attached to the udev device. The next
+ * list entry can be retrieved with udev_list_entry_get_next(),
+ * which returns #NULL if no more entries exist. The tag string
+ * can be retrieved from the list entry by udev_list_entry_get_name().
+ *
+ * Returns: the first entry of the tag list
+ **/
+_public_ struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device)
+{
+        if (udev_device == NULL)
+                return NULL;
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        return udev_list_get_entry(&udev_device->tags_list);
+}
+
+/**
+ * udev_device_has_tag:
+ * @udev_device: udev device
+ * @tag: tag name
+ *
+ * Check if a given device has a certain tag associated.
+ *
+ * Returns: 1 if the tag is found. 0 otherwise.
+ **/
+_public_ int udev_device_has_tag(struct udev_device *udev_device, const char *tag)
+{
+        struct udev_list_entry *list_entry;
+
+        if (udev_device == NULL)
+                return false;
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        list_entry = udev_device_get_tags_list_entry(udev_device);
+        if (udev_list_entry_get_by_name(list_entry, tag) != NULL)
+                return true;
+        return false;
+}
+
+#define ENVP_SIZE                        128
+#define MONITOR_BUF_SIZE                4096
+static int update_envp_monitor_buf(struct udev_device *udev_device)
+{
+        struct udev_list_entry *list_entry;
+        char *s;
+        size_t l;
+        unsigned int i;
+
+        /* monitor buffer of property strings */
+        free(udev_device->monitor_buf);
+        udev_device->monitor_buf_len = 0;
+        udev_device->monitor_buf = malloc(MONITOR_BUF_SIZE);
+        if (udev_device->monitor_buf == NULL)
+                return -ENOMEM;
+
+        /* envp array, strings will point into monitor buffer */
+        if (udev_device->envp == NULL)
+                udev_device->envp = malloc(sizeof(char *) * ENVP_SIZE);
+        if (udev_device->envp == NULL)
+                return -ENOMEM;
+
+        i = 0;
+        s = udev_device->monitor_buf;
+        l = MONITOR_BUF_SIZE;
+        udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
+                const char *key;
+
+                key = udev_list_entry_get_name(list_entry);
+                /* skip private variables */
+                if (key[0] == '.')
+                        continue;
+
+                /* add string to envp array */
+                udev_device->envp[i++] = s;
+                if (i+1 >= ENVP_SIZE)
+                        return -EINVAL;
+
+                /* add property string to monitor buffer */
+                l = util_strpcpyl(&s, l, key, "=", udev_list_entry_get_value(list_entry), NULL);
+                if (l == 0)
+                        return -EINVAL;
+                /* advance past the trailing '\0' that util_strpcpyl() guarantees */
+                s++;
+                l--;
+        }
+        udev_device->envp[i] = NULL;
+        udev_device->monitor_buf_len = s - udev_device->monitor_buf;
+        udev_device->envp_uptodate = true;
+        return 0;
+}
+
+char **udev_device_get_properties_envp(struct udev_device *udev_device)
+{
+        if (!udev_device->envp_uptodate)
+                if (update_envp_monitor_buf(udev_device) != 0)
+                        return NULL;
+        return udev_device->envp;
+}
+
+ssize_t udev_device_get_properties_monitor_buf(struct udev_device *udev_device, const char **buf)
+{
+        if (!udev_device->envp_uptodate)
+                if (update_envp_monitor_buf(udev_device) != 0)
+                        return -EINVAL;
+        *buf = udev_device->monitor_buf;
+        return udev_device->monitor_buf_len;
+}
+
+int udev_device_set_action(struct udev_device *udev_device, const char *action)
+{
+        free(udev_device->action);
+        udev_device->action = strdup(action);
+        if (udev_device->action == NULL)
+                return -ENOMEM;
+        udev_device_add_property(udev_device, "ACTION", udev_device->action);
+        return 0;
+}
+
+int udev_device_get_devlink_priority(struct udev_device *udev_device)
+{
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        return udev_device->devlink_priority;
+}
+
+int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio)
+{
+         udev_device->devlink_priority = prio;
+        return 0;
+}
+
+int udev_device_get_watch_handle(struct udev_device *udev_device)
+{
+        if (!udev_device->info_loaded)
+                udev_device_read_db(udev_device, NULL);
+        return udev_device->watch_handle;
+}
+
+int udev_device_set_watch_handle(struct udev_device *udev_device, int handle)
+{
+        udev_device->watch_handle = handle;
+        return 0;
+}
+
+bool udev_device_get_db_persist(struct udev_device *udev_device)
+{
+        return udev_device->db_persist;
+}
+
+void udev_device_set_db_persist(struct udev_device *udev_device)
+{
+        udev_device->db_persist = true;
+}
diff --git a/src/libudev/libudev-enumerate.c b/src/libudev/libudev-enumerate.c
new file mode 100644
index 0000000000..172965511b
--- /dev/null
+++ b/src/libudev/libudev-enumerate.c
@@ -0,0 +1,956 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <dirent.h>
+#include <fnmatch.h>
+#include <stdbool.h>
+#include <sys/stat.h>
+#include <sys/param.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+/**
+ * SECTION:libudev-enumerate
+ * @short_description: lookup and sort sys devices
+ *
+ * Lookup devices in the sys filesystem, filter devices by properties,
+ * and return a sorted list of devices.
+ */
+
+struct syspath {
+        char *syspath;
+        size_t len;
+};
+
+/**
+ * udev_enumerate:
+ *
+ * Opaque object representing one device lookup/sort context.
+ */
+struct udev_enumerate {
+        struct udev *udev;
+        int refcount;
+        struct udev_list sysattr_match_list;
+        struct udev_list sysattr_nomatch_list;
+        struct udev_list subsystem_match_list;
+        struct udev_list subsystem_nomatch_list;
+        struct udev_list sysname_match_list;
+        struct udev_list properties_match_list;
+        struct udev_list tags_match_list;
+        struct udev_device *parent_match;
+        struct udev_list devices_list;
+        struct syspath *devices;
+        unsigned int devices_cur;
+        unsigned int devices_max;
+        bool devices_uptodate:1;
+        bool match_is_initialized;
+};
+
+/**
+ * udev_enumerate_new:
+ * @udev: udev library context
+ *
+ * Create an enumeration context to scan /sys.
+ *
+ * Returns: an enumeration context.
+ **/
+_public_ struct udev_enumerate *udev_enumerate_new(struct udev *udev)
+{
+        struct udev_enumerate *udev_enumerate;
+
+        udev_enumerate = calloc(1, sizeof(struct udev_enumerate));
+        if (udev_enumerate == NULL)
+                return NULL;
+        udev_enumerate->refcount = 1;
+        udev_enumerate->udev = udev;
+        udev_list_init(udev, &udev_enumerate->sysattr_match_list, false);
+        udev_list_init(udev, &udev_enumerate->sysattr_nomatch_list, false);
+        udev_list_init(udev, &udev_enumerate->subsystem_match_list, true);
+        udev_list_init(udev, &udev_enumerate->subsystem_nomatch_list, true);
+        udev_list_init(udev, &udev_enumerate->sysname_match_list, true);
+        udev_list_init(udev, &udev_enumerate->properties_match_list, false);
+        udev_list_init(udev, &udev_enumerate->tags_match_list, true);
+        udev_list_init(udev, &udev_enumerate->devices_list, false);
+        return udev_enumerate;
+}
+
+/**
+ * udev_enumerate_ref:
+ * @udev_enumerate: context
+ *
+ * Take a reference of a enumeration context.
+ *
+ * Returns: the passed enumeration context
+ **/
+_public_ struct udev_enumerate *udev_enumerate_ref(struct udev_enumerate *udev_enumerate)
+{
+        if (udev_enumerate == NULL)
+                return NULL;
+        udev_enumerate->refcount++;
+        return udev_enumerate;
+}
+
+/**
+ * udev_enumerate_unref:
+ * @udev_enumerate: context
+ *
+ * Drop a reference of an enumeration context. If the refcount reaches zero,
+ * all resources of the enumeration context will be released.
+ *
+ * Returns: the passed enumeration context if it has still an active reference, or #NULL otherwise.
+ **/
+_public_ struct udev_enumerate *udev_enumerate_unref(struct udev_enumerate *udev_enumerate)
+{
+        unsigned int i;
+
+        if (udev_enumerate == NULL)
+                return NULL;
+        udev_enumerate->refcount--;
+        if (udev_enumerate->refcount > 0)
+                return udev_enumerate;
+        udev_list_cleanup(&udev_enumerate->sysattr_match_list);
+        udev_list_cleanup(&udev_enumerate->sysattr_nomatch_list);
+        udev_list_cleanup(&udev_enumerate->subsystem_match_list);
+        udev_list_cleanup(&udev_enumerate->subsystem_nomatch_list);
+        udev_list_cleanup(&udev_enumerate->sysname_match_list);
+        udev_list_cleanup(&udev_enumerate->properties_match_list);
+        udev_list_cleanup(&udev_enumerate->tags_match_list);
+        udev_device_unref(udev_enumerate->parent_match);
+        udev_list_cleanup(&udev_enumerate->devices_list);
+        for (i = 0; i < udev_enumerate->devices_cur; i++)
+                free(udev_enumerate->devices[i].syspath);
+        free(udev_enumerate->devices);
+        free(udev_enumerate);
+        return NULL;
+}
+
+/**
+ * udev_enumerate_get_udev:
+ * @udev_enumerate: context
+ *
+ * Get the udev library context.
+ *
+ * Returns: a pointer to the context.
+ */
+_public_ struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate)
+{
+        if (udev_enumerate == NULL)
+                return NULL;
+        return udev_enumerate->udev;
+}
+
+static int syspath_add(struct udev_enumerate *udev_enumerate, const char *syspath)
+{
+        char *path;
+        struct syspath *entry;
+
+        /* double array size if needed */
+        if (udev_enumerate->devices_cur >= udev_enumerate->devices_max) {
+                struct syspath *buf;
+                unsigned int add;
+
+                add = udev_enumerate->devices_max;
+                if (add < 1024)
+                        add = 1024;
+                buf = realloc(udev_enumerate->devices, (udev_enumerate->devices_max + add) * sizeof(struct syspath));
+                if (buf == NULL)
+                        return -ENOMEM;
+                udev_enumerate->devices = buf;
+                udev_enumerate->devices_max += add;
+        }
+
+        path = strdup(syspath);
+        if (path == NULL)
+                return -ENOMEM;
+        entry = &udev_enumerate->devices[udev_enumerate->devices_cur];
+        entry->syspath = path;
+        entry->len = strlen(path);
+        udev_enumerate->devices_cur++;
+        udev_enumerate->devices_uptodate = false;
+        return 0;
+}
+
+static int syspath_cmp(const void *p1, const void *p2)
+{
+        const struct syspath *path1 = p1;
+        const struct syspath *path2 = p2;
+        size_t len;
+        int ret;
+
+        len = MIN(path1->len, path2->len);
+        ret = memcmp(path1->syspath, path2->syspath, len);
+        if (ret == 0) {
+                if (path1->len < path2->len)
+                        ret = -1;
+                else if (path1->len > path2->len)
+                        ret = 1;
+        }
+        return ret;
+}
+
+/* For devices that should be moved to the absolute end of the list */
+static bool devices_delay_end(struct udev *udev, const char *syspath)
+{
+        static const char *delay_device_list[] = {
+                "/block/md",
+                "/block/dm-",
+                NULL
+        };
+        int i;
+
+        for (i = 0; delay_device_list[i] != NULL; i++) {
+                if (strstr(syspath + strlen("/sys"), delay_device_list[i]) != NULL)
+                        return true;
+        }
+        return false;
+}
+
+/* For devices that should just be moved a little bit later, just
+ * before the point where some common path prefix changes. Returns the
+ * number of characters that make up that common prefix */
+static size_t devices_delay_later(struct udev *udev, const char *syspath)
+{
+        const char *c;
+
+        /* For sound cards the control device must be enumerated last
+         * to make sure it's the final device node that gets ACLs
+         * applied. Applications rely on this fact and use ACL changes
+         * on the control node as an indicator that the ACL change of
+         * the entire sound card completed. The kernel makes this
+         * guarantee when creating those devices, and hence we should
+         * too when enumerating them. */
+
+        if ((c = strstr(syspath, "/sound/card"))) {
+                c += 11;
+                c += strcspn(c, "/");
+
+                if (startswith(c, "/controlC"))
+                        return c - syspath + 1;
+        }
+
+        return 0;
+}
+
+/**
+ * udev_enumerate_get_list_entry:
+ * @udev_enumerate: context
+ *
+ * Get the first entry of the sorted list of device paths.
+ *
+ * Returns: a udev_list_entry.
+ */
+_public_ struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate)
+{
+        if (udev_enumerate == NULL)
+                return NULL;
+        if (!udev_enumerate->devices_uptodate) {
+                unsigned int i;
+                unsigned int max;
+                struct syspath *prev = NULL, *move_later = NULL;
+                size_t move_later_prefix = 0;
+
+                udev_list_cleanup(&udev_enumerate->devices_list);
+                qsort(udev_enumerate->devices, udev_enumerate->devices_cur, sizeof(struct syspath), syspath_cmp);
+
+                max = udev_enumerate->devices_cur;
+                for (i = 0; i < max; i++) {
+                        struct syspath *entry = &udev_enumerate->devices[i];
+
+                        /* skip duplicated entries */
+                        if (prev != NULL &&
+                            entry->len == prev->len &&
+                            memcmp(entry->syspath, prev->syspath, entry->len) == 0)
+                                continue;
+                        prev = entry;
+
+                        /* skip to be delayed devices, and add them to the end of the list */
+                        if (devices_delay_end(udev_enumerate->udev, entry->syspath)) {
+                                syspath_add(udev_enumerate, entry->syspath);
+                                /* need to update prev here for the case realloc() gives a different address */
+                                prev = &udev_enumerate->devices[i];
+                                continue;
+                        }
+
+                        /* skip to be delayed devices, and move the to
+                         * the point where the prefix changes. We can
+                         * only move one item at a time. */
+                        if (!move_later) {
+                                move_later_prefix = devices_delay_later(udev_enumerate->udev, entry->syspath);
+
+                                if (move_later_prefix > 0) {
+                                        move_later = entry;
+                                        continue;
+                                }
+                        }
+
+                        if (move_later &&
+                            strncmp(entry->syspath, move_later->syspath, move_later_prefix) != 0) {
+
+                                udev_list_entry_add(&udev_enumerate->devices_list, move_later->syspath, NULL);
+                                move_later = NULL;
+                        }
+
+                        udev_list_entry_add(&udev_enumerate->devices_list, entry->syspath, NULL);
+                }
+
+                if (move_later)
+                        udev_list_entry_add(&udev_enumerate->devices_list, move_later->syspath, NULL);
+
+                /* add and cleanup delayed devices from end of list */
+                for (i = max; i < udev_enumerate->devices_cur; i++) {
+                        struct syspath *entry = &udev_enumerate->devices[i];
+
+                        udev_list_entry_add(&udev_enumerate->devices_list, entry->syspath, NULL);
+                        free(entry->syspath);
+                }
+                udev_enumerate->devices_cur = max;
+
+                udev_enumerate->devices_uptodate = true;
+        }
+        return udev_list_get_entry(&udev_enumerate->devices_list);
+}
+
+/**
+ * udev_enumerate_add_match_subsystem:
+ * @udev_enumerate: context
+ * @subsystem: filter for a subsystem of the device to include in the list
+ *
+ * Match only devices belonging to a certain kernel subsystem.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (subsystem == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->subsystem_match_list, subsystem, NULL) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_nomatch_subsystem:
+ * @udev_enumerate: context
+ * @subsystem: filter for a subsystem of the device to exclude from the list
+ *
+ * Match only devices not belonging to a certain kernel subsystem.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (subsystem == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->subsystem_nomatch_list, subsystem, NULL) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_match_sysattr:
+ * @udev_enumerate: context
+ * @sysattr: filter for a sys attribute at the device to include in the list
+ * @value: optional value of the sys attribute
+ *
+ * Match only devices with a certain /sys device attribute.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (sysattr == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->sysattr_match_list, sysattr, value) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_nomatch_sysattr:
+ * @udev_enumerate: context
+ * @sysattr: filter for a sys attribute at the device to exclude from the list
+ * @value: optional value of the sys attribute
+ *
+ * Match only devices not having a certain /sys device attribute.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (sysattr == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->sysattr_nomatch_list, sysattr, value) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+static int match_sysattr_value(struct udev_device *dev, const char *sysattr, const char *match_val)
+{
+        const char *val = NULL;
+        bool match = false;
+
+        val = udev_device_get_sysattr_value(dev, sysattr);
+        if (val == NULL)
+                goto exit;
+        if (match_val == NULL) {
+                match = true;
+                goto exit;
+        }
+        if (fnmatch(match_val, val, 0) == 0) {
+                match = true;
+                goto exit;
+        }
+exit:
+        return match;
+}
+
+/**
+ * udev_enumerate_add_match_property:
+ * @udev_enumerate: context
+ * @property: filter for a property of the device to include in the list
+ * @value: value of the property
+ *
+ * Match only devices with a certain property.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (property == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->properties_match_list, property, value) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_match_tag:
+ * @udev_enumerate: context
+ * @tag: filter for a tag of the device to include in the list
+ *
+ * Match only devices with a certain tag.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (tag == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->tags_match_list, tag, NULL) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_match_parent:
+ * @udev_enumerate: context
+ * @parent: parent device where to start searching
+ *
+ * Return the devices on the subtree of one given device. The parent
+ * itself is included in the list.
+ *
+ * A reference for the device is held until the udev_enumerate context
+ * is cleaned up.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (parent == NULL)
+                return 0;
+        if (udev_enumerate->parent_match != NULL)
+                udev_device_unref(udev_enumerate->parent_match);
+        udev_enumerate->parent_match = udev_device_ref(parent);
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_match_is_initialized:
+ * @udev_enumerate: context
+ *
+ * Match only devices which udev has set up already. This makes
+ * sure, that the device node permissions and context are properly set
+ * and that network devices are fully renamed.
+ *
+ * Usually, devices which are found in the kernel but not already
+ * handled by udev, have still pending events. Services should subscribe
+ * to monitor events and wait for these devices to become ready, instead
+ * of using uninitialized devices.
+ *
+ * For now, this will not affect devices which do not have a device node
+ * and are not network interfaces.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev_enumerate)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        udev_enumerate->match_is_initialized = true;
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_match_sysname:
+ * @udev_enumerate: context
+ * @sysname: filter for the name of the device to include in the list
+ *
+ * Match only devices with a given /sys device name.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (sysname == NULL)
+                return 0;
+        if (udev_list_entry_add(&udev_enumerate->sysname_match_list, sysname, NULL) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+static bool match_sysattr(struct udev_enumerate *udev_enumerate, struct udev_device *dev)
+{
+        struct udev_list_entry *list_entry;
+
+        /* skip list */
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysattr_nomatch_list)) {
+                if (match_sysattr_value(dev, udev_list_entry_get_name(list_entry),
+                                        udev_list_entry_get_value(list_entry)))
+                        return false;
+        }
+        /* include list */
+        if (udev_list_get_entry(&udev_enumerate->sysattr_match_list) != NULL) {
+                udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysattr_match_list)) {
+                        /* anything that does not match, will make it FALSE */
+                        if (!match_sysattr_value(dev, udev_list_entry_get_name(list_entry),
+                                                 udev_list_entry_get_value(list_entry)))
+                                return false;
+                }
+                return true;
+        }
+        return true;
+}
+
+static bool match_property(struct udev_enumerate *udev_enumerate, struct udev_device *dev)
+{
+        struct udev_list_entry *list_entry;
+        bool match = false;
+
+        /* no match always matches */
+        if (udev_list_get_entry(&udev_enumerate->properties_match_list) == NULL)
+                return true;
+
+        /* loop over matches */
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->properties_match_list)) {
+                const char *match_key = udev_list_entry_get_name(list_entry);
+                const char *match_value = udev_list_entry_get_value(list_entry);
+                struct udev_list_entry *property_entry;
+
+                /* loop over device properties */
+                udev_list_entry_foreach(property_entry, udev_device_get_properties_list_entry(dev)) {
+                        const char *dev_key = udev_list_entry_get_name(property_entry);
+                        const char *dev_value = udev_list_entry_get_value(property_entry);
+
+                        if (fnmatch(match_key, dev_key, 0) != 0)
+                                continue;
+                        if (match_value == NULL && dev_value == NULL) {
+                                match = true;
+                                goto out;
+                        }
+                        if (match_value == NULL || dev_value == NULL)
+                                continue;
+                        if (fnmatch(match_value, dev_value, 0) == 0) {
+                                match = true;
+                                goto out;
+                        }
+                }
+        }
+out:
+        return match;
+}
+
+static bool match_tag(struct udev_enumerate *udev_enumerate, struct udev_device *dev)
+{
+        struct udev_list_entry *list_entry;
+
+        /* no match always matches */
+        if (udev_list_get_entry(&udev_enumerate->tags_match_list) == NULL)
+                return true;
+
+        /* loop over matches */
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->tags_match_list))
+                if (!udev_device_has_tag(dev, udev_list_entry_get_name(list_entry)))
+                        return false;
+
+        return true;
+}
+
+static bool match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *dev)
+{
+        if (udev_enumerate->parent_match == NULL)
+                return true;
+
+        return startswith(udev_device_get_devpath(dev), udev_device_get_devpath(udev_enumerate->parent_match));
+}
+
+static bool match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname)
+{
+        struct udev_list_entry *list_entry;
+
+        if (udev_list_get_entry(&udev_enumerate->sysname_match_list) == NULL)
+                return true;
+
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->sysname_match_list)) {
+                if (fnmatch(udev_list_entry_get_name(list_entry), sysname, 0) != 0)
+                        continue;
+                return true;
+        }
+        return false;
+}
+
+static int scan_dir_and_add_devices(struct udev_enumerate *udev_enumerate,
+                                    const char *basedir, const char *subdir1, const char *subdir2)
+{
+        char path[UTIL_PATH_SIZE];
+        size_t l;
+        char *s;
+        DIR *dir;
+        struct dirent *dent;
+
+        s = path;
+        l = util_strpcpyl(&s, sizeof(path), "/sys/", basedir, NULL);
+        if (subdir1 != NULL)
+                l = util_strpcpyl(&s, l, "/", subdir1, NULL);
+        if (subdir2 != NULL)
+                util_strpcpyl(&s, l, "/", subdir2, NULL);
+        dir = opendir(path);
+        if (dir == NULL)
+                return -ENOENT;
+        for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                char syspath[UTIL_PATH_SIZE];
+                struct udev_device *dev;
+
+                if (dent->d_name[0] == '.')
+                        continue;
+
+                if (!match_sysname(udev_enumerate, dent->d_name))
+                        continue;
+
+                util_strscpyl(syspath, sizeof(syspath), path, "/", dent->d_name, NULL);
+                dev = udev_device_new_from_syspath(udev_enumerate->udev, syspath);
+                if (dev == NULL)
+                        continue;
+
+                if (udev_enumerate->match_is_initialized) {
+                        /*
+                         * All devices with a device node or network interfaces
+                         * possibly need udev to adjust the device node permission
+                         * or context, or rename the interface before it can be
+                         * reliably used from other processes.
+                         *
+                         * For now, we can only check these types of devices, we
+                         * might not store a database, and have no way to find out
+                         * for all other types of devices.
+                         */
+                        if (!udev_device_get_is_initialized(dev) &&
+                            (major(udev_device_get_devnum(dev)) > 0 || udev_device_get_ifindex(dev) > 0))
+                                goto nomatch;
+                }
+                if (!match_parent(udev_enumerate, dev))
+                        goto nomatch;
+                if (!match_tag(udev_enumerate, dev))
+                        goto nomatch;
+                if (!match_property(udev_enumerate, dev))
+                        goto nomatch;
+                if (!match_sysattr(udev_enumerate, dev))
+                        goto nomatch;
+
+                syspath_add(udev_enumerate, udev_device_get_syspath(dev));
+nomatch:
+                udev_device_unref(dev);
+        }
+        closedir(dir);
+        return 0;
+}
+
+static bool match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem)
+{
+        struct udev_list_entry *list_entry;
+
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_nomatch_list)) {
+                if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
+                        return false;
+        }
+        if (udev_list_get_entry(&udev_enumerate->subsystem_match_list) != NULL) {
+                udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->subsystem_match_list)) {
+                        if (fnmatch(udev_list_entry_get_name(list_entry), subsystem, 0) == 0)
+                                return true;
+                }
+                return false;
+        }
+        return true;
+}
+
+static int scan_dir(struct udev_enumerate *udev_enumerate, const char *basedir, const char *subdir, const char *subsystem)
+{
+        char path[UTIL_PATH_SIZE];
+        DIR *dir;
+        struct dirent *dent;
+
+        util_strscpyl(path, sizeof(path), "/sys/", basedir, NULL);
+        dir = opendir(path);
+        if (dir == NULL)
+                return -1;
+        for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                if (dent->d_name[0] == '.')
+                        continue;
+                if (!match_subsystem(udev_enumerate, subsystem != NULL ? subsystem : dent->d_name))
+                        continue;
+                scan_dir_and_add_devices(udev_enumerate, basedir, dent->d_name, subdir);
+        }
+        closedir(dir);
+        return 0;
+}
+
+/**
+ * udev_enumerate_add_syspath:
+ * @udev_enumerate: context
+ * @syspath: path of a device
+ *
+ * Add a device to the list of devices, to retrieve it back sorted in dependency order.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath)
+{
+        struct udev_device *udev_device;
+
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+        if (syspath == NULL)
+                return 0;
+        /* resolve to real syspath */
+        udev_device = udev_device_new_from_syspath(udev_enumerate->udev, syspath);
+        if (udev_device == NULL)
+                return -EINVAL;
+        syspath_add(udev_enumerate, udev_device_get_syspath(udev_device));
+        udev_device_unref(udev_device);
+        return 0;
+}
+
+static int scan_devices_tags(struct udev_enumerate *udev_enumerate)
+{
+        struct udev_list_entry *list_entry;
+
+        /* scan only tagged devices, use tags reverse-index, instead of searching all devices in /sys */
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->tags_match_list)) {
+                DIR *dir;
+                struct dirent *dent;
+                char path[UTIL_PATH_SIZE];
+
+                util_strscpyl(path, sizeof(path), "/run/udev/tags/", udev_list_entry_get_name(list_entry), NULL);
+                dir = opendir(path);
+                if (dir == NULL)
+                        continue;
+                for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                        struct udev_device *dev;
+
+                        if (dent->d_name[0] == '.')
+                                continue;
+
+                        dev = udev_device_new_from_device_id(udev_enumerate->udev, dent->d_name);
+                        if (dev == NULL)
+                                continue;
+
+                        if (!match_subsystem(udev_enumerate, udev_device_get_subsystem(dev)))
+                                goto nomatch;
+                        if (!match_sysname(udev_enumerate, udev_device_get_sysname(dev)))
+                                goto nomatch;
+                        if (!match_parent(udev_enumerate, dev))
+                                goto nomatch;
+                        if (!match_property(udev_enumerate, dev))
+                                goto nomatch;
+                        if (!match_sysattr(udev_enumerate, dev))
+                                goto nomatch;
+
+                        syspath_add(udev_enumerate, udev_device_get_syspath(dev));
+nomatch:
+                        udev_device_unref(dev);
+                }
+                closedir(dir);
+        }
+        return 0;
+}
+
+static int parent_add_child(struct udev_enumerate *enumerate, const char *path)
+{
+        struct udev_device *dev;
+
+        dev = udev_device_new_from_syspath(enumerate->udev, path);
+        if (dev == NULL)
+                return -ENODEV;
+
+        if (!match_subsystem(enumerate, udev_device_get_subsystem(dev)))
+                return 0;
+        if (!match_sysname(enumerate, udev_device_get_sysname(dev)))
+                return 0;
+        if (!match_property(enumerate, dev))
+                return 0;
+        if (!match_sysattr(enumerate, dev))
+                return 0;
+
+        syspath_add(enumerate, udev_device_get_syspath(dev));
+        udev_device_unref(dev);
+        return 1;
+}
+
+static int parent_crawl_children(struct udev_enumerate *enumerate, const char *path, int maxdepth)
+{
+        DIR *d;
+        struct dirent *dent;
+
+        d = opendir(path);
+        if (d == NULL)
+                return -errno;
+
+        for (dent = readdir(d); dent != NULL; dent = readdir(d)) {
+                char *child;
+
+                if (dent->d_name[0] == '.')
+                        continue;
+                if (dent->d_type != DT_DIR)
+                        continue;
+                if (asprintf(&child, "%s/%s", path, dent->d_name) < 0)
+                        continue;
+                parent_add_child(enumerate, child);
+                if (maxdepth > 0)
+                        parent_crawl_children(enumerate, child, maxdepth-1);
+                free(child);
+        }
+
+        closedir(d);
+        return 0;
+}
+
+static int scan_devices_children(struct udev_enumerate *enumerate)
+{
+        const char *path;
+
+        path = udev_device_get_syspath(enumerate->parent_match);
+        parent_add_child(enumerate, path);
+        return parent_crawl_children(enumerate, path, 256);
+}
+
+static int scan_devices_all(struct udev_enumerate *udev_enumerate)
+{
+        struct stat statbuf;
+
+        if (stat("/sys/subsystem", &statbuf) == 0) {
+                /* we have /subsystem/, forget all the old stuff */
+                scan_dir(udev_enumerate, "subsystem", "devices", NULL);
+        } else {
+                scan_dir(udev_enumerate, "bus", "devices", NULL);
+                scan_dir(udev_enumerate, "class", NULL, NULL);
+        }
+        return 0;
+}
+
+/**
+ * udev_enumerate_scan_devices:
+ * @udev_enumerate: udev enumeration context
+ *
+ * Scan /sys for all devices which match the given filters. No matches
+ * will return all currently available devices.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ **/
+_public_ int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate)
+{
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+
+        /* efficiently lookup tags only, we maintain a reverse-index */
+        if (udev_list_get_entry(&udev_enumerate->tags_match_list) != NULL)
+                return scan_devices_tags(udev_enumerate);
+
+        /* walk the subtree of one parent device only */
+        if (udev_enumerate->parent_match != NULL)
+                return scan_devices_children(udev_enumerate);
+
+        /* scan devices of all subsystems */
+        return scan_devices_all(udev_enumerate);
+}
+
+/**
+ * udev_enumerate_scan_subsystems:
+ * @udev_enumerate: udev enumeration context
+ *
+ * Scan /sys for all kernel subsystems, including buses, classes, drivers.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ **/
+_public_ int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate)
+{
+        struct stat statbuf;
+        const char *subsysdir;
+
+        if (udev_enumerate == NULL)
+                return -EINVAL;
+
+        /* all kernel modules */
+        if (match_subsystem(udev_enumerate, "module"))
+                scan_dir_and_add_devices(udev_enumerate, "module", NULL, NULL);
+
+        if (stat("/sys/subsystem", &statbuf) == 0)
+                subsysdir = "subsystem";
+        else
+                subsysdir = "bus";
+
+        /* all subsystems (only buses support coldplug) */
+        if (match_subsystem(udev_enumerate, "subsystem"))
+                scan_dir_and_add_devices(udev_enumerate, subsysdir, NULL, NULL);
+
+        /* all subsystem drivers */
+        if (match_subsystem(udev_enumerate, "drivers"))
+                scan_dir(udev_enumerate, subsysdir, "drivers", "drivers");
+        return 0;
+}
diff --git a/src/libudev/libudev-hwdb-def.h b/src/libudev/libudev-hwdb-def.h
new file mode 100644
index 0000000000..e167e2805b
--- /dev/null
+++ b/src/libudev/libudev-hwdb-def.h
@@ -0,0 +1,74 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifndef _LIBUDEV_HWDB_DEF_H_
+#define _LIBUDEV_HWDB_DEF_H_
+
+#include "sparse-endian.h"
+
+#define HWDB_SIG { 'K', 'S', 'L', 'P', 'H', 'H', 'R', 'H' }
+
+/* on-disk trie objects */
+_packed_ struct trie_header_f {
+        uint8_t signature[8];
+
+        /* version of tool which created the file */
+        le64_t tool_version;
+        le64_t file_size;
+
+        /* size of structures to allow them to grow */
+        le64_t header_size;
+        le64_t node_size;
+        le64_t child_entry_size;
+        le64_t value_entry_size;
+
+        /* offset of the root trie node */
+        le64_t nodes_root_off;
+
+        /* size of the nodes and string section */
+        le64_t nodes_len;
+        le64_t strings_len;
+};
+
+_packed_ struct trie_node_f {
+        /* prefix of lookup string, shared by all children  */
+        le64_t prefix_off;
+        /* size of children entry array appended to the node */
+        uint8_t children_count;
+        uint8_t padding[7];
+        /* size of value entry array appended to the node */
+        le64_t values_count;
+};
+
+/* array of child entries, follows directly the node record */
+_packed_ struct trie_child_entry_f {
+        /* index of the child node */
+        uint8_t c;
+        uint8_t padding[7];
+        /* offset of the child node */
+        le64_t child_off;
+};
+
+/* array of value entries, follows directly the node record/child array */
+_packed_ struct trie_value_entry_f {
+        le64_t key_off;
+        le64_t value_off;
+};
+
+#endif
diff --git a/src/libudev/libudev-hwdb.c b/src/libudev/libudev-hwdb.c
new file mode 100644
index 0000000000..751b34209e
--- /dev/null
+++ b/src/libudev/libudev-hwdb.c
@@ -0,0 +1,392 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2012 Kay Sievers <kay@vrfy.org>
+  Copyright 2008 Alan Jenkins <alan.christopher.jenkins@googlemail.com>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <inttypes.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <fnmatch.h>
+#include <getopt.h>
+#include <sys/mman.h>
+
+#include "libudev-private.h"
+#include "libudev-hwdb-def.h"
+
+/**
+ * SECTION:libudev-hwdb
+ * @short_description: retrieve properties from the hardware database
+ *
+ * Libudev hardware database interface.
+ */
+
+/**
+ * udev_hwdb:
+ *
+ * Opaque object representing the hardware database.
+ */
+struct udev_hwdb {
+        struct udev *udev;
+        int refcount;
+
+        FILE *f;
+        struct stat st;
+        union {
+                struct trie_header_f *head;
+                const char *map;
+        };
+
+        struct udev_list properties_list;
+};
+
+struct linebuf {
+        char bytes[LINE_MAX];
+        size_t size;
+        size_t len;
+};
+
+static void linebuf_init(struct linebuf *buf) {
+        buf->size = 0;
+        buf->len = 0;
+}
+
+static const char *linebuf_get(struct linebuf *buf) {
+        if (buf->len + 1 >= sizeof(buf->bytes))
+                return NULL;
+        buf->bytes[buf->len] = '\0';
+        return buf->bytes;
+}
+
+static bool linebuf_add(struct linebuf *buf, const char *s, size_t len) {
+        if (buf->len + len >= sizeof(buf->bytes))
+                return false;
+        memcpy(buf->bytes + buf->len, s, len);
+        buf->len += len;
+        return true;
+}
+
+static bool linebuf_add_char(struct linebuf *buf, char c)
+{
+        if (buf->len + 1 >= sizeof(buf->bytes))
+                return false;
+        buf->bytes[buf->len++] = c;
+        return true;
+}
+
+static void linebuf_rem(struct linebuf *buf, size_t count) {
+        assert(buf->len >= count);
+        buf->len -= count;
+}
+
+static void linebuf_rem_char(struct linebuf *buf) {
+        linebuf_rem(buf, 1);
+}
+
+static const struct trie_child_entry_f *trie_node_children(struct udev_hwdb *hwdb, const struct trie_node_f *node) {
+        return (const struct trie_child_entry_f *)((const char *)node + le64toh(hwdb->head->node_size));
+}
+
+static const struct trie_value_entry_f *trie_node_values(struct udev_hwdb *hwdb, const struct trie_node_f *node) {
+        const char *base = (const char *)node;
+
+        base += le64toh(hwdb->head->node_size);
+        base += node->children_count * le64toh(hwdb->head->child_entry_size);
+        return (const struct trie_value_entry_f *)base;
+}
+
+static const struct trie_node_f *trie_node_from_off(struct udev_hwdb *hwdb, le64_t off) {
+        return (const struct trie_node_f *)(hwdb->map + le64toh(off));
+}
+
+static const char *trie_string(struct udev_hwdb *hwdb, le64_t off) {
+        return hwdb->map + le64toh(off);
+}
+
+static int trie_children_cmp_f(const void *v1, const void *v2) {
+        const struct trie_child_entry_f *n1 = v1;
+        const struct trie_child_entry_f *n2 = v2;
+
+        return n1->c - n2->c;
+}
+
+static const struct trie_node_f *node_lookup_f(struct udev_hwdb *hwdb, const struct trie_node_f *node, uint8_t c) {
+        struct trie_child_entry_f *child;
+        struct trie_child_entry_f search;
+
+        search.c = c;
+        child = bsearch(&search, trie_node_children(hwdb, node), node->children_count,
+                        le64toh(hwdb->head->child_entry_size), trie_children_cmp_f);
+        if (child)
+                return trie_node_from_off(hwdb, child->child_off);
+        return NULL;
+}
+
+static int hwdb_add_property(struct udev_hwdb *hwdb, const char *key, const char *value) {
+        /* TODO: add sub-matches (+) against DMI data */
+        if (key[0] != ' ')
+                return 0;
+        if (udev_list_entry_add(&hwdb->properties_list, key+1, value) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+static int trie_fnmatch_f(struct udev_hwdb *hwdb, const struct trie_node_f *node, size_t p,
+                          struct linebuf *buf, const char *search) {
+        size_t len;
+        size_t i;
+        const char *prefix;
+        int err;
+
+        prefix = trie_string(hwdb, node->prefix_off);
+        len = strlen(prefix + p);
+        linebuf_add(buf, prefix + p, len);
+
+        for (i = 0; i < node->children_count; i++) {
+                const struct trie_child_entry_f *child = &trie_node_children(hwdb, node)[i];
+
+                linebuf_add_char(buf, child->c);
+                err = trie_fnmatch_f(hwdb, trie_node_from_off(hwdb, child->child_off), 0, buf, search);
+                if (err < 0)
+                        return err;
+                linebuf_rem_char(buf);
+        }
+
+        if (node->values_count && fnmatch(linebuf_get(buf), search, 0) == 0)
+                for (i = 0; i < node->values_count; i++) {
+                        err = hwdb_add_property(hwdb, trie_string(hwdb, trie_node_values(hwdb, node)[i].key_off),
+                                                trie_string(hwdb, trie_node_values(hwdb, node)[i].value_off));
+                        if (err < 0)
+                                return err;
+                }
+
+        linebuf_rem(buf, len);
+        return 0;
+}
+
+static int trie_search_f(struct udev_hwdb *hwdb, const char *search) {
+        struct linebuf buf;
+        const struct trie_node_f *node;
+        size_t i = 0;
+        int err;
+
+        linebuf_init(&buf);
+
+        node = trie_node_from_off(hwdb, hwdb->head->nodes_root_off);
+        while (node) {
+                const struct trie_node_f *child;
+                size_t p = 0;
+
+                if (node->prefix_off) {
+                        uint8_t c;
+
+                        for (; (c = trie_string(hwdb, node->prefix_off)[p]); p++) {
+                                if (c == '*' || c == '?' || c == '[')
+                                        return trie_fnmatch_f(hwdb, node, p, &buf, search + i + p);
+                                if (c != search[i + p])
+                                        return 0;
+                        }
+                        i += p;
+                }
+
+                child = node_lookup_f(hwdb, node, '*');
+                if (child) {
+                        linebuf_add_char(&buf, '*');
+                        err = trie_fnmatch_f(hwdb, child, 0, &buf, search + i);
+                        if (err < 0)
+                                return err;
+                        linebuf_rem_char(&buf);
+                }
+
+                child = node_lookup_f(hwdb, node, '?');
+                if (child) {
+                        linebuf_add_char(&buf, '?');
+                        err = trie_fnmatch_f(hwdb, child, 0, &buf, search + i);
+                        if (err < 0)
+                                return err;
+                        linebuf_rem_char(&buf);
+                }
+
+                child = node_lookup_f(hwdb, node, '[');
+                if (child) {
+                        linebuf_add_char(&buf, '[');
+                        err = trie_fnmatch_f(hwdb, child, 0, &buf, search + i);
+                        if (err < 0)
+                                return err;
+                        linebuf_rem_char(&buf);
+                }
+
+                if (search[i] == '\0') {
+                        size_t n;
+
+                        for (n = 0; n < node->values_count; n++) {
+                                err = hwdb_add_property(hwdb, trie_string(hwdb, trie_node_values(hwdb, node)[n].key_off),
+                                                        trie_string(hwdb, trie_node_values(hwdb, node)[n].value_off));
+                                if (err < 0)
+                                        return err;
+                        }
+                        return 0;
+                }
+
+                child = node_lookup_f(hwdb, node, search[i]);
+                node = child;
+                i++;
+        }
+        return 0;
+}
+
+/**
+ * udev_hwdb_new:
+ * @udev: udev library context
+ *
+ * Create a hardware database context to query properties for devices.
+ *
+ * Returns: a hwdb context.
+ **/
+_public_ struct udev_hwdb *udev_hwdb_new(struct udev *udev) {
+        struct udev_hwdb *hwdb;
+        const char sig[] = HWDB_SIG;
+
+        hwdb = new0(struct udev_hwdb, 1);
+        if (!hwdb)
+                return NULL;
+
+        hwdb->refcount = 1;
+        udev_list_init(udev, &hwdb->properties_list, true);
+
+        hwdb->f = fopen("/etc/udev/hwdb.bin", "re");
+        if (!hwdb->f) {
+                log_debug("error reading /etc/udev/hwdb.bin: %m");
+                udev_hwdb_unref(hwdb);
+                return NULL;
+        }
+
+        if (fstat(fileno(hwdb->f), &hwdb->st) < 0 ||
+            (size_t)hwdb->st.st_size < offsetof(struct trie_header_f, strings_len) + 8) {
+                log_debug("error reading /etc/udev/hwdb.bin: %m");
+                udev_hwdb_unref(hwdb);
+                return NULL;
+        }
+
+        hwdb->map = mmap(0, hwdb->st.st_size, PROT_READ, MAP_SHARED, fileno(hwdb->f), 0);
+        if (hwdb->map == MAP_FAILED) {
+                log_debug("error mapping /etc/udev/hwdb.bin: %m");
+                udev_hwdb_unref(hwdb);
+                return NULL;
+        }
+
+        if (memcmp(hwdb->map, sig, sizeof(hwdb->head->signature)) != 0 ||
+            (size_t)hwdb->st.st_size != le64toh(hwdb->head->file_size)) {
+                log_debug("error recognizing the format of /etc/udev/hwdb.bin");
+                udev_hwdb_unref(hwdb);
+                return NULL;
+        }
+
+        log_debug("=== trie on-disk ===\n");
+        log_debug("tool version:          %llu", (unsigned long long)le64toh(hwdb->head->tool_version));
+        log_debug("file size:        %8llu bytes\n", (unsigned long long)hwdb->st.st_size);
+        log_debug("header size       %8llu bytes\n", (unsigned long long)le64toh(hwdb->head->header_size));
+        log_debug("strings           %8llu bytes\n", (unsigned long long)le64toh(hwdb->head->strings_len));
+        log_debug("nodes             %8llu bytes\n", (unsigned long long)le64toh(hwdb->head->nodes_len));
+        return hwdb;
+}
+
+/**
+ * udev_hwdb_ref:
+ * @hwdb: context
+ *
+ * Take a reference of a hwdb context.
+ *
+ * Returns: the passed enumeration context
+ **/
+_public_ struct udev_hwdb *udev_hwdb_ref(struct udev_hwdb *hwdb) {
+        if (!hwdb)
+                return NULL;
+        hwdb->refcount++;
+        return hwdb;
+}
+
+/**
+ * udev_hwdb_unref:
+ * @hwdb: context
+ *
+ * Drop a reference of a hwdb context. If the refcount reaches zero,
+ * all resources of the hwdb context will be released.
+ *
+ * Returns: the passed hwdb context if it has still an active reference, or #NULL otherwise.
+ **/
+_public_ struct udev_hwdb *udev_hwdb_unref(struct udev_hwdb *hwdb) {
+        if (!hwdb)
+                return NULL;
+        hwdb->refcount--;
+        if (hwdb->refcount > 0)
+                return hwdb;
+        if (hwdb->map)
+                munmap((void *)hwdb->map, hwdb->st.st_size);
+        if (hwdb->f)
+                fclose(hwdb->f);
+        udev_list_cleanup(&hwdb->properties_list);
+        free(hwdb);
+        return NULL;
+}
+
+bool udev_hwdb_validate(struct udev_hwdb *hwdb) {
+        struct stat st;
+
+        if (!hwdb)
+                return false;
+        if (!hwdb->f)
+                return false;
+        if (fstat(fileno(hwdb->f), &st) < 0)
+                return true;
+        if (timespec_load(&hwdb->st.st_mtim) != timespec_load(&st.st_mtim))
+                return true;
+        return false;
+}
+
+/**
+ * udev_hwdb_get_properties_list_entry:
+ * @hwdb: context
+ * @modalias: modalias string
+ * @flags: (unused)
+ *
+ * Lookup a matching device in the hardware database. The lookup key is a
+ * modalias string, whose formats are defined for the Linux kernel modules.
+ * Examples are: pci:v00008086d00001C2D*, usb:v04F2pB221*. The first entry
+ * of a list of retrieved properties is returned.
+ *
+ * Returns: a udev_list_entry.
+ */
+_public_ struct udev_list_entry *udev_hwdb_get_properties_list_entry(struct udev_hwdb *hwdb, const char *modalias, unsigned int flags) {
+        int err;
+
+        if (!hwdb->f) {
+                errno = EINVAL;
+                return NULL;
+        }
+
+        udev_list_cleanup(&hwdb->properties_list);
+        err = trie_search_f(hwdb, modalias);
+        if (err < 0) {
+                errno = -err;
+                return NULL;
+        }
+        return udev_list_get_entry(&hwdb->properties_list);
+}
diff --git a/src/libudev/libudev-list.c b/src/libudev/libudev-list.c
new file mode 100644
index 0000000000..59ba69e279
--- /dev/null
+++ b/src/libudev/libudev-list.c
@@ -0,0 +1,355 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+/**
+ * SECTION:libudev-list
+ * @short_description: list operation
+ *
+ * Libudev list operations.
+ */
+
+/**
+ * udev_list_entry:
+ *
+ * Opaque object representing one entry in a list. An entry contains
+ * contains a name, and optionally a value.
+ */
+struct udev_list_entry {
+        struct udev_list_node node;
+        struct udev_list *list;
+        char *name;
+        char *value;
+        int num;
+};
+
+/* the list's head points to itself if empty */
+void udev_list_node_init(struct udev_list_node *list)
+{
+        list->next = list;
+        list->prev = list;
+}
+
+int udev_list_node_is_empty(struct udev_list_node *list)
+{
+        return list->next == list;
+}
+
+static void udev_list_node_insert_between(struct udev_list_node *new,
+                                          struct udev_list_node *prev,
+                                          struct udev_list_node *next)
+{
+        next->prev = new;
+        new->next = next;
+        new->prev = prev;
+        prev->next = new;
+}
+
+void udev_list_node_append(struct udev_list_node *new, struct udev_list_node *list)
+{
+        udev_list_node_insert_between(new, list->prev, list);
+}
+
+void udev_list_node_remove(struct udev_list_node *entry)
+{
+        struct udev_list_node *prev = entry->prev;
+        struct udev_list_node *next = entry->next;
+
+        next->prev = prev;
+        prev->next = next;
+
+        entry->prev = NULL;
+        entry->next = NULL;
+}
+
+/* return list entry which embeds this node */
+static inline struct udev_list_entry *list_node_to_entry(struct udev_list_node *node)
+{
+        return container_of(node, struct udev_list_entry, node);
+}
+
+void udev_list_init(struct udev *udev, struct udev_list *list, bool unique)
+{
+        memset(list, 0x00, sizeof(struct udev_list));
+        list->udev = udev;
+        list->unique = unique;
+        udev_list_node_init(&list->node);
+}
+
+/* insert entry into a list as the last element  */
+void udev_list_entry_append(struct udev_list_entry *new, struct udev_list *list)
+{
+        /* inserting before the list head make the node the last node in the list */
+        udev_list_node_insert_between(&new->node, list->node.prev, &list->node);
+        new->list = list;
+}
+
+/* insert entry into a list, before a given existing entry */
+void udev_list_entry_insert_before(struct udev_list_entry *new, struct udev_list_entry *entry)
+{
+        udev_list_node_insert_between(&new->node, entry->node.prev, &entry->node);
+        new->list = entry->list;
+}
+
+/* binary search in sorted array */
+static int list_search(struct udev_list *list, const char *name)
+{
+        unsigned int first, last;
+
+        first = 0;
+        last = list->entries_cur;
+        while (first < last) {
+                unsigned int i;
+                int cmp;
+
+                i = (first + last)/2;
+                cmp = strcmp(name, list->entries[i]->name);
+                if (cmp < 0)
+                        last = i;
+                else if (cmp > 0)
+                        first = i+1;
+                else
+                        return i;
+        }
+
+        /* not found, return negative insertion-index+1 */
+        return -(first+1);
+}
+
+struct udev_list_entry *udev_list_entry_add(struct udev_list *list, const char *name, const char *value)
+{
+        struct udev_list_entry *entry;
+        int i = 0;
+
+        if (list->unique) {
+                /* lookup existing name or insertion-index */
+                i = list_search(list, name);
+                if (i >= 0) {
+                        entry = list->entries[i];
+
+                        free(entry->value);
+                        if (value == NULL) {
+                                entry->value = NULL;
+                                return entry;
+                        }
+                        entry->value = strdup(value);
+                        if (entry->value == NULL)
+                                return NULL;
+                        return entry;
+                }
+        }
+
+        /* add new name */
+        entry = calloc(1, sizeof(struct udev_list_entry));
+        if (entry == NULL)
+                return NULL;
+        entry->name = strdup(name);
+        if (entry->name == NULL) {
+                free(entry);
+                return NULL;
+        }
+        if (value != NULL) {
+                entry->value = strdup(value);
+                if (entry->value == NULL) {
+                        free(entry->name);
+                        free(entry);
+                        return NULL;
+                }
+        }
+
+        if (list->unique) {
+                /* allocate or enlarge sorted array if needed */
+                if (list->entries_cur >= list->entries_max) {
+                        struct udev_list_entry **entries;
+                        unsigned int add;
+
+                        add = list->entries_max;
+                        if (add < 1)
+                                add = 64;
+                        entries = realloc(list->entries, (list->entries_max + add) * sizeof(struct udev_list_entry *));
+                        if (entries == NULL) {
+                                free(entry->name);
+                                free(entry->value);
+                                free(entry);
+                                return NULL;
+                        }
+                        list->entries = entries;
+                        list->entries_max += add;
+                }
+
+                /* the negative i returned the insertion index */
+                i = (-i)-1;
+
+                /* insert into sorted list */
+                if ((unsigned int)i < list->entries_cur)
+                        udev_list_entry_insert_before(entry, list->entries[i]);
+                else
+                        udev_list_entry_append(entry, list);
+
+                /* insert into sorted array */
+                memmove(&list->entries[i+1], &list->entries[i],
+                        (list->entries_cur - i) * sizeof(struct udev_list_entry *));
+                list->entries[i] = entry;
+                list->entries_cur++;
+        } else {
+                udev_list_entry_append(entry, list);
+        }
+
+        return entry;
+}
+
+void udev_list_entry_delete(struct udev_list_entry *entry)
+{
+        if (entry->list->entries != NULL) {
+                int i;
+                struct udev_list *list = entry->list;
+
+                /* remove entry from sorted array */
+                i = list_search(list, entry->name);
+                if (i >= 0) {
+                        memmove(&list->entries[i], &list->entries[i+1],
+                                ((list->entries_cur-1) - i) * sizeof(struct udev_list_entry *));
+                        list->entries_cur--;
+                }
+        }
+
+        udev_list_node_remove(&entry->node);
+        free(entry->name);
+        free(entry->value);
+        free(entry);
+}
+
+void udev_list_cleanup(struct udev_list *list)
+{
+        struct udev_list_entry *entry_loop;
+        struct udev_list_entry *entry_tmp;
+
+        free(list->entries);
+        list->entries = NULL;
+        list->entries_cur = 0;
+        list->entries_max = 0;
+        udev_list_entry_foreach_safe(entry_loop, entry_tmp, udev_list_get_entry(list))
+                udev_list_entry_delete(entry_loop);
+}
+
+struct udev_list_entry *udev_list_get_entry(struct udev_list *list)
+{
+        if (udev_list_node_is_empty(&list->node))
+                return NULL;
+        return list_node_to_entry(list->node.next);
+}
+
+/**
+ * udev_list_entry_get_next:
+ * @list_entry: current entry
+ *
+ * Get the next entry from the list.
+ *
+ * Returns: udev_list_entry, #NULL if no more entries are available.
+ */
+_public_ struct udev_list_entry *udev_list_entry_get_next(struct udev_list_entry *list_entry)
+{
+        struct udev_list_node *next;
+
+        if (list_entry == NULL)
+                return NULL;
+        next = list_entry->node.next;
+        /* empty list or no more entries */
+        if (next == &list_entry->list->node)
+                return NULL;
+        return list_node_to_entry(next);
+}
+
+/**
+ * udev_list_entry_get_by_name:
+ * @list_entry: current entry
+ * @name: name string to match
+ *
+ * Lookup an entry in the list with a certain name.
+ *
+ * Returns: udev_list_entry, #NULL if no matching entry is found.
+ */
+_public_ struct udev_list_entry *udev_list_entry_get_by_name(struct udev_list_entry *list_entry, const char *name)
+{
+        int i;
+
+        if (list_entry == NULL)
+                return NULL;
+
+        if (!list_entry->list->unique)
+                return NULL;
+
+        i = list_search(list_entry->list, name);
+        if (i < 0)
+                return NULL;
+        return list_entry->list->entries[i];
+}
+
+/**
+ * udev_list_entry_get_name:
+ * @list_entry: current entry
+ *
+ * Get the name of a list entry.
+ *
+ * Returns: the name string of this entry.
+ */
+_public_ const char *udev_list_entry_get_name(struct udev_list_entry *list_entry)
+{
+        if (list_entry == NULL)
+                return NULL;
+        return list_entry->name;
+}
+
+/**
+ * udev_list_entry_get_value:
+ * @list_entry: current entry
+ *
+ * Get the value of list entry.
+ *
+ * Returns: the value string of this entry.
+ */
+_public_ const char *udev_list_entry_get_value(struct udev_list_entry *list_entry)
+{
+        if (list_entry == NULL)
+                return NULL;
+        return list_entry->value;
+}
+
+int udev_list_entry_get_num(struct udev_list_entry *list_entry)
+{
+        if (list_entry == NULL)
+                return -EINVAL;
+        return list_entry->num;
+}
+
+void udev_list_entry_set_num(struct udev_list_entry *list_entry, int num)
+{
+        if (list_entry == NULL)
+                return;
+        list_entry->num = num;
+}
diff --git a/src/libudev/libudev-monitor.c b/src/libudev/libudev-monitor.c
new file mode 100644
index 0000000000..b02ea8808c
--- /dev/null
+++ b/src/libudev/libudev-monitor.c
@@ -0,0 +1,782 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <dirent.h>
+#include <sys/poll.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <arpa/inet.h>
+#include <linux/netlink.h>
+#include <linux/filter.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+#include "socket-util.h"
+
+/**
+ * SECTION:libudev-monitor
+ * @short_description: device event source
+ *
+ * Connects to a device event source.
+ */
+
+/**
+ * udev_monitor:
+ *
+ * Opaque object handling an event source.
+ */
+struct udev_monitor {
+        struct udev *udev;
+        int refcount;
+        int sock;
+        union sockaddr_union snl;
+        union sockaddr_union snl_trusted_sender;
+        union sockaddr_union snl_destination;
+        socklen_t addrlen;
+        struct udev_list filter_subsystem_list;
+        struct udev_list filter_tag_list;
+        bool bound;
+};
+
+enum udev_monitor_netlink_group {
+        UDEV_MONITOR_NONE,
+        UDEV_MONITOR_KERNEL,
+        UDEV_MONITOR_UDEV,
+};
+
+#define UDEV_MONITOR_MAGIC                0xfeedcafe
+struct udev_monitor_netlink_header {
+        /* "libudev" prefix to distinguish libudev and kernel messages */
+        char prefix[8];
+        /*
+         * magic to protect against daemon <-> library message format mismatch
+         * used in the kernel from socket filter rules; needs to be stored in network order
+         */
+        unsigned int magic;
+        /* total length of header structure known to the sender */
+        unsigned int header_size;
+        /* properties string buffer */
+        unsigned int properties_off;
+        unsigned int properties_len;
+        /*
+         * hashes of primary device properties strings, to let libudev subscribers
+         * use in-kernel socket filters; values need to be stored in network order
+         */
+        unsigned int filter_subsystem_hash;
+        unsigned int filter_devtype_hash;
+        unsigned int filter_tag_bloom_hi;
+        unsigned int filter_tag_bloom_lo;
+};
+
+static struct udev_monitor *udev_monitor_new(struct udev *udev)
+{
+        struct udev_monitor *udev_monitor;
+
+        udev_monitor = calloc(1, sizeof(struct udev_monitor));
+        if (udev_monitor == NULL)
+                return NULL;
+        udev_monitor->refcount = 1;
+        udev_monitor->udev = udev;
+        udev_list_init(udev, &udev_monitor->filter_subsystem_list, false);
+        udev_list_init(udev, &udev_monitor->filter_tag_list, true);
+        return udev_monitor;
+}
+
+struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const char *name, int fd)
+{
+        struct udev_monitor *udev_monitor;
+        unsigned int group;
+
+        if (udev == NULL)
+                return NULL;
+
+        if (name == NULL)
+                group = UDEV_MONITOR_NONE;
+        else if (strcmp(name, "udev") == 0)
+                group = UDEV_MONITOR_UDEV;
+        else if (strcmp(name, "kernel") == 0)
+                group = UDEV_MONITOR_KERNEL;
+        else
+                return NULL;
+
+        udev_monitor = udev_monitor_new(udev);
+        if (udev_monitor == NULL)
+                return NULL;
+
+        if (fd < 0) {
+                udev_monitor->sock = socket(PF_NETLINK, SOCK_RAW|SOCK_CLOEXEC|SOCK_NONBLOCK, NETLINK_KOBJECT_UEVENT);
+                if (udev_monitor->sock == -1) {
+                        udev_err(udev, "error getting socket: %m\n");
+                        free(udev_monitor);
+                        return NULL;
+                }
+        } else {
+                udev_monitor->bound = true;
+                udev_monitor->sock = fd;
+        }
+
+        udev_monitor->snl.nl.nl_family = AF_NETLINK;
+        udev_monitor->snl.nl.nl_groups = group;
+
+        /* default destination for sending */
+        udev_monitor->snl_destination.nl.nl_family = AF_NETLINK;
+        udev_monitor->snl_destination.nl.nl_groups = UDEV_MONITOR_UDEV;
+
+        return udev_monitor;
+}
+
+/**
+ * udev_monitor_new_from_netlink:
+ * @udev: udev library context
+ * @name: name of event source
+ *
+ * Create new udev monitor and connect to a specified event
+ * source. Valid sources identifiers are "udev" and "kernel".
+ *
+ * Applications should usually not connect directly to the
+ * "kernel" events, because the devices might not be useable
+ * at that time, before udev has configured them, and created
+ * device nodes. Accessing devices at the same time as udev,
+ * might result in unpredictable behavior. The "udev" events
+ * are sent out after udev has finished its event processing,
+ * all rules have been processed, and needed device nodes are
+ * created.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev monitor.
+ *
+ * Returns: a new udev monitor, or #NULL, in case of an error
+ **/
+_public_ struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev, const char *name)
+{
+        return udev_monitor_new_from_netlink_fd(udev, name, -1);
+}
+
+static inline void bpf_stmt(struct sock_filter *inss, unsigned int *i,
+                            unsigned short code, unsigned int data)
+{
+        struct sock_filter *ins = &inss[*i];
+
+        ins->code = code;
+        ins->k = data;
+        (*i)++;
+}
+
+static inline void bpf_jmp(struct sock_filter *inss, unsigned int *i,
+                           unsigned short code, unsigned int data,
+                           unsigned short jt, unsigned short jf)
+{
+        struct sock_filter *ins = &inss[*i];
+
+        ins->code = code;
+        ins->jt = jt;
+        ins->jf = jf;
+        ins->k = data;
+        (*i)++;
+}
+
+/**
+ * udev_monitor_filter_update:
+ * @udev_monitor: monitor
+ *
+ * Update the installed socket filter. This is only needed,
+ * if the filter was removed or changed.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_monitor_filter_update(struct udev_monitor *udev_monitor)
+{
+        struct sock_filter ins[512];
+        struct sock_fprog filter;
+        unsigned int i;
+        struct udev_list_entry *list_entry;
+        int err;
+
+        if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) == NULL &&
+            udev_list_get_entry(&udev_monitor->filter_tag_list) == NULL)
+                return 0;
+
+        memset(ins, 0x00, sizeof(ins));
+        i = 0;
+
+        /* load magic in A */
+        bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, magic));
+        /* jump if magic matches */
+        bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, UDEV_MONITOR_MAGIC, 1, 0);
+        /* wrong magic, pass packet */
+        bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff);
+
+        if (udev_list_get_entry(&udev_monitor->filter_tag_list) != NULL) {
+                int tag_matches;
+
+                /* count tag matches, to calculate end of tag match block */
+                tag_matches = 0;
+                udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list))
+                        tag_matches++;
+
+                /* add all tags matches */
+                udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) {
+                        uint64_t tag_bloom_bits = util_string_bloom64(udev_list_entry_get_name(list_entry));
+                        uint32_t tag_bloom_hi = tag_bloom_bits >> 32;
+                        uint32_t tag_bloom_lo = tag_bloom_bits & 0xffffffff;
+
+                        /* load device bloom bits in A */
+                        bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_tag_bloom_hi));
+                        /* clear bits (tag bits & bloom bits) */
+                        bpf_stmt(ins, &i, BPF_ALU|BPF_AND|BPF_K, tag_bloom_hi);
+                        /* jump to next tag if it does not match */
+                        bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, tag_bloom_hi, 0, 3);
+
+                        /* load device bloom bits in A */
+                        bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_tag_bloom_lo));
+                        /* clear bits (tag bits & bloom bits) */
+                        bpf_stmt(ins, &i, BPF_ALU|BPF_AND|BPF_K, tag_bloom_lo);
+                        /* jump behind end of tag match block if tag matches */
+                        tag_matches--;
+                        bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, tag_bloom_lo, 1 + (tag_matches * 6), 0);
+                }
+
+                /* nothing matched, drop packet */
+                bpf_stmt(ins, &i, BPF_RET|BPF_K, 0);
+        }
+
+        /* add all subsystem matches */
+        if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) != NULL) {
+                udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_subsystem_list)) {
+                        unsigned int hash = util_string_hash32(udev_list_entry_get_name(list_entry));
+
+                        /* load device subsystem value in A */
+                        bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_subsystem_hash));
+                        if (udev_list_entry_get_value(list_entry) == NULL) {
+                                /* jump if subsystem does not match */
+                                bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 1);
+                        } else {
+                                /* jump if subsystem does not match */
+                                bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 3);
+
+                                /* load device devtype value in A */
+                                bpf_stmt(ins, &i, BPF_LD|BPF_W|BPF_ABS, offsetof(struct udev_monitor_netlink_header, filter_devtype_hash));
+                                /* jump if value does not match */
+                                hash = util_string_hash32(udev_list_entry_get_value(list_entry));
+                                bpf_jmp(ins, &i, BPF_JMP|BPF_JEQ|BPF_K, hash, 0, 1);
+                        }
+
+                        /* matched, pass packet */
+                        bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff);
+
+                        if (i+1 >= ELEMENTSOF(ins))
+                                return -1;
+                }
+
+                /* nothing matched, drop packet */
+                bpf_stmt(ins, &i, BPF_RET|BPF_K, 0);
+        }
+
+        /* matched, pass packet */
+        bpf_stmt(ins, &i, BPF_RET|BPF_K, 0xffffffff);
+
+        /* install filter */
+        memset(&filter, 0x00, sizeof(filter));
+        filter.len = i;
+        filter.filter = ins;
+        err = setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));
+        return err;
+}
+
+int udev_monitor_allow_unicast_sender(struct udev_monitor *udev_monitor, struct udev_monitor *sender)
+{
+        udev_monitor->snl_trusted_sender.nl.nl_pid = sender->snl.nl.nl_pid;
+        return 0;
+}
+/**
+ * udev_monitor_enable_receiving:
+ * @udev_monitor: the monitor which should receive events
+ *
+ * Binds the @udev_monitor socket to the event source.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor)
+{
+        int err = 0;
+        const int on = 1;
+
+        if (udev_monitor->snl.nl.nl_family == 0)
+                return -EINVAL;
+
+        udev_monitor_filter_update(udev_monitor);
+
+        if (!udev_monitor->bound) {
+                err = bind(udev_monitor->sock,
+                           &udev_monitor->snl.sa, sizeof(struct sockaddr_nl));
+                if (err == 0)
+                        udev_monitor->bound = true;
+        }
+
+        if (err >= 0) {
+                union sockaddr_union snl;
+                socklen_t addrlen;
+
+                /*
+                 * get the address the kernel has assigned us
+                 * it is usually, but not necessarily the pid
+                 */
+                addrlen = sizeof(struct sockaddr_nl);
+                err = getsockname(udev_monitor->sock, &snl.sa, &addrlen);
+                if (err == 0)
+                        udev_monitor->snl.nl.nl_pid = snl.nl.nl_pid;
+        } else {
+                udev_err(udev_monitor->udev, "bind failed: %m\n");
+                return err;
+        }
+
+        /* enable receiving of sender credentials */
+        setsockopt(udev_monitor->sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
+        return 0;
+}
+
+/**
+ * udev_monitor_set_receive_buffer_size:
+ * @udev_monitor: the monitor which should receive events
+ * @size: the size in bytes
+ *
+ * Set the size of the kernel socket buffer. This call needs the
+ * appropriate privileges to succeed.
+ *
+ * Returns: 0 on success, otherwise -1 on error.
+ */
+_public_ int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size)
+{
+        if (udev_monitor == NULL)
+                return -1;
+        return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size));
+}
+
+int udev_monitor_disconnect(struct udev_monitor *udev_monitor)
+{
+        int err;
+
+        err = close(udev_monitor->sock);
+        udev_monitor->sock = -1;
+        return err;
+}
+
+/**
+ * udev_monitor_ref:
+ * @udev_monitor: udev monitor
+ *
+ * Take a reference of a udev monitor.
+ *
+ * Returns: the passed udev monitor
+ **/
+_public_ struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_monitor)
+{
+        if (udev_monitor == NULL)
+                return NULL;
+        udev_monitor->refcount++;
+        return udev_monitor;
+}
+
+/**
+ * udev_monitor_unref:
+ * @udev_monitor: udev monitor
+ *
+ * Drop a reference of a udev monitor. If the refcount reaches zero,
+ * the bound socket will be closed, and the resources of the monitor
+ * will be released.
+ *
+ * Returns: the passed udev monitor if it has still an active reference, or #NULL otherwise.
+ **/
+_public_ struct udev_monitor *udev_monitor_unref(struct udev_monitor *udev_monitor)
+{
+        if (udev_monitor == NULL)
+                return NULL;
+        udev_monitor->refcount--;
+        if (udev_monitor->refcount > 0)
+                return udev_monitor;
+        if (udev_monitor->sock >= 0)
+                close(udev_monitor->sock);
+        udev_list_cleanup(&udev_monitor->filter_subsystem_list);
+        udev_list_cleanup(&udev_monitor->filter_tag_list);
+        free(udev_monitor);
+        return NULL;
+}
+
+/**
+ * udev_monitor_get_udev:
+ * @udev_monitor: udev monitor
+ *
+ * Retrieve the udev library context the monitor was created with.
+ *
+ * Returns: the udev library context
+ **/
+_public_ struct udev *udev_monitor_get_udev(struct udev_monitor *udev_monitor)
+{
+        if (udev_monitor == NULL)
+                return NULL;
+        return udev_monitor->udev;
+}
+
+/**
+ * udev_monitor_get_fd:
+ * @udev_monitor: udev monitor
+ *
+ * Retrieve the socket file descriptor associated with the monitor.
+ *
+ * Returns: the socket file descriptor
+ **/
+_public_ int udev_monitor_get_fd(struct udev_monitor *udev_monitor)
+{
+        if (udev_monitor == NULL)
+                return -1;
+        return udev_monitor->sock;
+}
+
+static int passes_filter(struct udev_monitor *udev_monitor, struct udev_device *udev_device)
+{
+        struct udev_list_entry *list_entry;
+
+        if (udev_list_get_entry(&udev_monitor->filter_subsystem_list) == NULL)
+                goto tag;
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_subsystem_list)) {
+                const char *subsys = udev_list_entry_get_name(list_entry);
+                const char *dsubsys = udev_device_get_subsystem(udev_device);
+                const char *devtype;
+                const char *ddevtype;
+
+                if (strcmp(dsubsys, subsys) != 0)
+                        continue;
+
+                devtype = udev_list_entry_get_value(list_entry);
+                if (devtype == NULL)
+                        goto tag;
+                ddevtype = udev_device_get_devtype(udev_device);
+                if (ddevtype == NULL)
+                        continue;
+                if (strcmp(ddevtype, devtype) == 0)
+                        goto tag;
+        }
+        return 0;
+
+tag:
+        if (udev_list_get_entry(&udev_monitor->filter_tag_list) == NULL)
+                return 1;
+        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_monitor->filter_tag_list)) {
+                const char *tag = udev_list_entry_get_name(list_entry);
+
+                if (udev_device_has_tag(udev_device, tag))
+                        return 1;
+        }
+        return 0;
+}
+
+/**
+ * udev_monitor_receive_device:
+ * @udev_monitor: udev monitor
+ *
+ * Receive data from the udev monitor socket, allocate a new udev
+ * device, fill in the received data, and return the device.
+ *
+ * Only socket connections with uid=0 are accepted.
+ *
+ * The monitor socket is by default set to NONBLOCK. A variant of poll() on
+ * the file descriptor returned by udev_monitor_get_fd() should to be used to
+ * wake up when new devices arrive, or alternatively the file descriptor
+ * switched into blocking mode.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, in case of an error
+ **/
+_public_ struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monitor)
+{
+        struct udev_device *udev_device;
+        struct msghdr smsg;
+        struct iovec iov;
+        char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+        struct cmsghdr *cmsg;
+        union sockaddr_union snl;
+        struct ucred *cred;
+        char buf[8192];
+        ssize_t buflen;
+        ssize_t bufpos;
+        struct udev_monitor_netlink_header *nlh;
+
+retry:
+        if (udev_monitor == NULL)
+                return NULL;
+        iov.iov_base = &buf;
+        iov.iov_len = sizeof(buf);
+        memset (&smsg, 0x00, sizeof(struct msghdr));
+        smsg.msg_iov = &iov;
+        smsg.msg_iovlen = 1;
+        smsg.msg_control = cred_msg;
+        smsg.msg_controllen = sizeof(cred_msg);
+
+        if (udev_monitor->snl.nl.nl_family != 0) {
+                smsg.msg_name = &snl;
+                smsg.msg_namelen = sizeof(snl);
+        }
+
+        buflen = recvmsg(udev_monitor->sock, &smsg, 0);
+        if (buflen < 0) {
+                if (errno != EINTR)
+                        udev_dbg(udev_monitor->udev, "unable to receive message\n");
+                return NULL;
+        }
+
+        if (buflen < 32 || (size_t)buflen >= sizeof(buf)) {
+                udev_dbg(udev_monitor->udev, "invalid message length\n");
+                return NULL;
+        }
+
+        if (udev_monitor->snl.nl.nl_family != 0) {
+                if (snl.nl.nl_groups == 0) {
+                        /* unicast message, check if we trust the sender */
+                        if (udev_monitor->snl_trusted_sender.nl.nl_pid == 0 ||
+                            snl.nl.nl_pid != udev_monitor->snl_trusted_sender.nl.nl_pid) {
+                                udev_dbg(udev_monitor->udev, "unicast netlink message ignored\n");
+                                return NULL;
+                        }
+                } else if (snl.nl.nl_groups == UDEV_MONITOR_KERNEL) {
+                        if (snl.nl.nl_pid > 0) {
+                                udev_dbg(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n",
+                                     snl.nl.nl_pid);
+                                return NULL;
+                        }
+                }
+        }
+
+        cmsg = CMSG_FIRSTHDR(&smsg);
+        if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
+                udev_dbg(udev_monitor->udev, "no sender credentials received, message ignored\n");
+                return NULL;
+        }
+
+        cred = (struct ucred *)CMSG_DATA(cmsg);
+        if (cred->uid != 0) {
+                udev_dbg(udev_monitor->udev, "sender uid=%d, message ignored\n", cred->uid);
+                return NULL;
+        }
+
+        if (memcmp(buf, "libudev", 8) == 0) {
+                /* udev message needs proper version magic */
+                nlh = (struct udev_monitor_netlink_header *) buf;
+                if (nlh->magic != htonl(UDEV_MONITOR_MAGIC)) {
+                        udev_err(udev_monitor->udev, "unrecognized message signature (%x != %x)\n",
+                            nlh->magic, htonl(UDEV_MONITOR_MAGIC));
+                        return NULL;
+                }
+                if (nlh->properties_off+32 > (size_t)buflen)
+                        return NULL;
+                bufpos = nlh->properties_off;
+        } else {
+                /* kernel message with header */
+                bufpos = strlen(buf) + 1;
+                if ((size_t)bufpos < sizeof("a@/d") || bufpos >= buflen) {
+                        udev_dbg(udev_monitor->udev, "invalid message length\n");
+                        return NULL;
+                }
+
+                /* check message header */
+                if (strstr(buf, "@/") == NULL) {
+                        udev_dbg(udev_monitor->udev, "unrecognized message header\n");
+                        return NULL;
+                }
+        }
+
+        udev_device = udev_device_new(udev_monitor->udev);
+        if (udev_device == NULL)
+                return NULL;
+        udev_device_set_info_loaded(udev_device);
+
+        while (bufpos < buflen) {
+                char *key;
+                size_t keylen;
+
+                key = &buf[bufpos];
+                keylen = strlen(key);
+                if (keylen == 0)
+                        break;
+                bufpos += keylen + 1;
+                udev_device_add_property_from_string_parse(udev_device, key);
+        }
+
+        if (udev_device_add_property_from_string_parse_finish(udev_device) < 0) {
+                udev_dbg(udev_monitor->udev, "missing values, invalid device\n");
+                udev_device_unref(udev_device);
+                return NULL;
+        }
+
+        /* skip device, if it does not pass the current filter */
+        if (!passes_filter(udev_monitor, udev_device)) {
+                struct pollfd pfd[1];
+                int rc;
+
+                udev_device_unref(udev_device);
+
+                /* if something is queued, get next device */
+                pfd[0].fd = udev_monitor->sock;
+                pfd[0].events = POLLIN;
+                rc = poll(pfd, 1, 0);
+                if (rc > 0)
+                        goto retry;
+                return NULL;
+        }
+
+        return udev_device;
+}
+
+int udev_monitor_send_device(struct udev_monitor *udev_monitor,
+                             struct udev_monitor *destination, struct udev_device *udev_device)
+{
+        const char *buf;
+        ssize_t blen;
+        ssize_t count;
+        struct msghdr smsg;
+        struct iovec iov[2];
+        const char *val;
+        struct udev_monitor_netlink_header nlh;
+        struct udev_list_entry *list_entry;
+        uint64_t tag_bloom_bits;
+
+        if (udev_monitor->snl.nl.nl_family == 0)
+                return -EINVAL;
+
+        blen = udev_device_get_properties_monitor_buf(udev_device, &buf);
+        if (blen < 32)
+                return -EINVAL;
+
+        /* add versioned header */
+        memset(&nlh, 0x00, sizeof(struct udev_monitor_netlink_header));
+        memcpy(nlh.prefix, "libudev", 8);
+        nlh.magic = htonl(UDEV_MONITOR_MAGIC);
+        nlh.header_size = sizeof(struct udev_monitor_netlink_header);
+        val = udev_device_get_subsystem(udev_device);
+        nlh.filter_subsystem_hash = htonl(util_string_hash32(val));
+        val = udev_device_get_devtype(udev_device);
+        if (val != NULL)
+                nlh.filter_devtype_hash = htonl(util_string_hash32(val));
+        iov[0].iov_base = &nlh;
+        iov[0].iov_len = sizeof(struct udev_monitor_netlink_header);
+
+        /* add tag bloom filter */
+        tag_bloom_bits = 0;
+        udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
+                tag_bloom_bits |= util_string_bloom64(udev_list_entry_get_name(list_entry));
+        if (tag_bloom_bits > 0) {
+                nlh.filter_tag_bloom_hi = htonl(tag_bloom_bits >> 32);
+                nlh.filter_tag_bloom_lo = htonl(tag_bloom_bits & 0xffffffff);
+        }
+
+        /* add properties list */
+        nlh.properties_off = iov[0].iov_len;
+        nlh.properties_len = blen;
+        iov[1].iov_base = (char *)buf;
+        iov[1].iov_len = blen;
+
+        memset(&smsg, 0x00, sizeof(struct msghdr));
+        smsg.msg_iov = iov;
+        smsg.msg_iovlen = 2;
+        /*
+         * Use custom address for target, or the default one.
+         *
+         * If we send to a multicast group, we will get
+         * ECONNREFUSED, which is expected.
+         */
+        if (destination != NULL)
+                smsg.msg_name = &destination->snl;
+        else
+                smsg.msg_name = &udev_monitor->snl_destination;
+        smsg.msg_namelen = sizeof(struct sockaddr_nl);
+        count = sendmsg(udev_monitor->sock, &smsg, 0);
+        udev_dbg(udev_monitor->udev, "passed %zi bytes to netlink monitor %p\n", count, udev_monitor);
+        return count;
+}
+
+/**
+ * udev_monitor_filter_add_match_subsystem_devtype:
+ * @udev_monitor: the monitor
+ * @subsystem: the subsystem value to match the incoming devices against
+ * @devtype: the devtype value to match the incoming devices against
+ *
+ * This filter is efficiently executed inside the kernel, and libudev subscribers
+ * will usually not be woken up for devices which do not match.
+ *
+ * The filter must be installed before the monitor is switched to listening mode.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_monitor_filter_add_match_subsystem_devtype(struct udev_monitor *udev_monitor, const char *subsystem, const char *devtype)
+{
+        if (udev_monitor == NULL)
+                return -EINVAL;
+        if (subsystem == NULL)
+                return -EINVAL;
+        if (udev_list_entry_add(&udev_monitor->filter_subsystem_list, subsystem, devtype) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_monitor_filter_add_match_tag:
+ * @udev_monitor: the monitor
+ * @tag: the name of a tag
+ *
+ * This filter is efficiently executed inside the kernel, and libudev subscribers
+ * will usually not be woken up for devices which do not match.
+ *
+ * The filter must be installed before the monitor is switched to listening mode.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_monitor_filter_add_match_tag(struct udev_monitor *udev_monitor, const char *tag)
+{
+        if (udev_monitor == NULL)
+                return -EINVAL;
+        if (tag == NULL)
+                return -EINVAL;
+        if (udev_list_entry_add(&udev_monitor->filter_tag_list, tag, NULL) == NULL)
+                return -ENOMEM;
+        return 0;
+}
+
+/**
+ * udev_monitor_filter_remove:
+ * @udev_monitor: monitor
+ *
+ * Remove all filters from monitor.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+_public_ int udev_monitor_filter_remove(struct udev_monitor *udev_monitor)
+{
+        static struct sock_fprog filter = { 0, NULL };
+
+        udev_list_cleanup(&udev_monitor->filter_subsystem_list);
+        return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));
+}
diff --git a/src/libudev/libudev-private.h b/src/libudev/libudev-private.h
new file mode 100644
index 0000000000..ff1cc8cefd
--- /dev/null
+++ b/src/libudev/libudev-private.h
@@ -0,0 +1,180 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifndef _LIBUDEV_PRIVATE_H_
+#define _LIBUDEV_PRIVATE_H_
+
+#include <syslog.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "libudev.h"
+#include "macro.h"
+#include "util.h"
+#include "mkdir.h"
+
+#define READ_END  0
+#define WRITE_END 1
+
+/* avoid (sometimes expensive) calculations of parameters for debug output */
+#define udev_log_cond(udev, prio, arg...) \
+  do { \
+    if (udev_get_log_priority(udev) >= prio) \
+      udev_log(udev, prio, __FILE__, __LINE__, __FUNCTION__, ## arg); \
+  } while (0)
+
+#define udev_dbg(udev, arg...) udev_log_cond(udev, LOG_DEBUG, ## arg)
+#define udev_info(udev, arg...) udev_log_cond(udev, LOG_INFO, ## arg)
+#define udev_err(udev, arg...) udev_log_cond(udev, LOG_ERR, ## arg)
+
+/* libudev.c */
+void udev_log(struct udev *udev,
+              int priority, const char *file, int line, const char *fn,
+              const char *format, ...)
+              __attribute__((format(printf, 6, 7)));
+int udev_get_rules_path(struct udev *udev, char **path[], usec_t *ts_usec[]);
+struct udev_list_entry *udev_add_property(struct udev *udev, const char *key, const char *value);
+struct udev_list_entry *udev_get_properties_list_entry(struct udev *udev);
+
+/* libudev-device.c */
+struct udev_device *udev_device_new(struct udev *udev);
+mode_t udev_device_get_devnode_mode(struct udev_device *udev_device);
+int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem);
+int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath);
+int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode);
+int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink);
+void udev_device_cleanup_devlinks_list(struct udev_device *udev_device);
+struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value);
+void udev_device_add_property_from_string_parse(struct udev_device *udev_device, const char *property);
+int udev_device_add_property_from_string_parse_finish(struct udev_device *udev_device);
+char **udev_device_get_properties_envp(struct udev_device *udev_device);
+ssize_t udev_device_get_properties_monitor_buf(struct udev_device *udev_device, const char **buf);
+int udev_device_read_db(struct udev_device *udev_device, const char *dbfile);
+int udev_device_read_uevent_file(struct udev_device *udev_device);
+int udev_device_set_action(struct udev_device *udev_device, const char *action);
+const char *udev_device_get_devpath_old(struct udev_device *udev_device);
+const char *udev_device_get_id_filename(struct udev_device *udev_device);
+void udev_device_set_is_initialized(struct udev_device *udev_device);
+int udev_device_add_tag(struct udev_device *udev_device, const char *tag);
+void udev_device_cleanup_tags_list(struct udev_device *udev_device);
+usec_t udev_device_get_usec_initialized(struct udev_device *udev_device);
+void udev_device_set_usec_initialized(struct udev_device *udev_device, usec_t usec_initialized);
+int udev_device_get_devlink_priority(struct udev_device *udev_device);
+int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio);
+int udev_device_get_watch_handle(struct udev_device *udev_device);
+int udev_device_set_watch_handle(struct udev_device *udev_device, int handle);
+int udev_device_get_ifindex(struct udev_device *udev_device);
+void udev_device_set_info_loaded(struct udev_device *device);
+bool udev_device_get_db_persist(struct udev_device *udev_device);
+void udev_device_set_db_persist(struct udev_device *udev_device);
+
+/* libudev-device-private.c */
+int udev_device_update_db(struct udev_device *udev_device);
+int udev_device_delete_db(struct udev_device *udev_device);
+int udev_device_tag_index(struct udev_device *dev, struct udev_device *dev_old, bool add);
+
+/* libudev-monitor.c - netlink/unix socket communication  */
+int udev_monitor_disconnect(struct udev_monitor *udev_monitor);
+int udev_monitor_allow_unicast_sender(struct udev_monitor *udev_monitor, struct udev_monitor *sender);
+int udev_monitor_send_device(struct udev_monitor *udev_monitor,
+                             struct udev_monitor *destination, struct udev_device *udev_device);
+struct udev_monitor *udev_monitor_new_from_netlink_fd(struct udev *udev, const char *name, int fd);
+
+/* libudev-list.c */
+struct udev_list_node {
+        struct udev_list_node *next, *prev;
+};
+struct udev_list {
+        struct udev *udev;
+        struct udev_list_node node;
+        struct udev_list_entry **entries;
+        unsigned int entries_cur;
+        unsigned int entries_max;
+        bool unique;
+};
+#define UDEV_LIST(list) struct udev_list_node list = { &(list), &(list) }
+void udev_list_node_init(struct udev_list_node *list);
+int udev_list_node_is_empty(struct udev_list_node *list);
+void udev_list_node_append(struct udev_list_node *new, struct udev_list_node *list);
+void udev_list_node_remove(struct udev_list_node *entry);
+#define udev_list_node_foreach(node, list) \
+        for (node = (list)->next; \
+             node != list; \
+             node = (node)->next)
+#define udev_list_node_foreach_safe(node, tmp, list) \
+        for (node = (list)->next, tmp = (node)->next; \
+             node != list; \
+             node = tmp, tmp = (tmp)->next)
+void udev_list_init(struct udev *udev, struct udev_list *list, bool unique);
+void udev_list_cleanup(struct udev_list *list);
+struct udev_list_entry *udev_list_get_entry(struct udev_list *list);
+struct udev_list_entry *udev_list_entry_add(struct udev_list *list, const char *name, const char *value);
+void udev_list_entry_delete(struct udev_list_entry *entry);
+void udev_list_entry_insert_before(struct udev_list_entry *new, struct udev_list_entry *entry);
+void udev_list_entry_append(struct udev_list_entry *new, struct udev_list *list);
+int udev_list_entry_get_num(struct udev_list_entry *list_entry);
+void udev_list_entry_set_num(struct udev_list_entry *list_entry, int num);
+#define udev_list_entry_foreach_safe(entry, tmp, first) \
+        for (entry = first, tmp = udev_list_entry_get_next(entry); \
+             entry != NULL; \
+             entry = tmp, tmp = udev_list_entry_get_next(tmp))
+
+/* libudev-queue.c */
+unsigned long long int udev_get_kernel_seqnum(struct udev *udev);
+int udev_queue_read_seqnum(FILE *queue_file, unsigned long long int *seqnum);
+ssize_t udev_queue_read_devpath(FILE *queue_file, char *devpath, size_t size);
+ssize_t udev_queue_skip_devpath(FILE *queue_file);
+
+/* libudev-queue-private.c */
+struct udev_queue_export *udev_queue_export_new(struct udev *udev);
+struct udev_queue_export *udev_queue_export_unref(struct udev_queue_export *udev_queue_export);
+void udev_queue_export_cleanup(struct udev_queue_export *udev_queue_export);
+int udev_queue_export_device_queued(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device);
+int udev_queue_export_device_finished(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device);
+
+/* libudev-hwdb.c */
+bool udev_hwdb_validate(struct udev_hwdb *hwdb);
+
+/* libudev-util.c */
+#define UTIL_PATH_SIZE                      1024
+#define UTIL_NAME_SIZE                       512
+#define UTIL_LINE_SIZE                     16384
+#define UDEV_ALLOWED_CHARS_INPUT        "/ $%?,"
+ssize_t util_get_sys_core_link_value(struct udev *udev, const char *slink, const char *syspath, char *value, size_t size);
+int util_resolve_sys_link(struct udev *udev, char *syspath, size_t size);
+int util_log_priority(const char *priority);
+size_t util_path_encode(const char *src, char *dest, size_t size);
+void util_remove_trailing_chars(char *path, char c);
+size_t util_strpcpy(char **dest, size_t size, const char *src);
+size_t util_strpcpyl(char **dest, size_t size, const char *src, ...) __attribute__((sentinel));
+size_t util_strscpy(char *dest, size_t size, const char *src);
+size_t util_strscpyl(char *dest, size_t size, const char *src, ...) __attribute__((sentinel));
+int util_replace_whitespace(const char *str, char *to, size_t len);
+int util_replace_chars(char *str, const char *white);
+unsigned int util_string_hash32(const char *key);
+uint64_t util_string_bloom64(const char *str);
+
+/* libudev-util-private.c */
+int util_delete_path(struct udev *udev, const char *path);
+uid_t util_lookup_user(struct udev *udev, const char *user);
+gid_t util_lookup_group(struct udev *udev, const char *group);
+int util_resolve_subsys_kernel(struct udev *udev, const char *string, char *result, size_t maxsize, int read_value);
+ssize_t print_kmsg(const char *fmt, ...) __attribute__((format(printf, 1, 2)));
+#endif
diff --git a/src/libudev/libudev-queue-private.c b/src/libudev/libudev-queue-private.c
new file mode 100644
index 0000000000..80d7ceef2b
--- /dev/null
+++ b/src/libudev/libudev-queue-private.c
@@ -0,0 +1,406 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+  Copyright 2009 Alan Jenkins <alan-jenkins@tuffmail.co.uk>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+/*
+ * DISCLAIMER - The file format mentioned here is private to udev/libudev,
+ *              and may be changed without notice.
+ *
+ * The udev event queue is exported as a binary log file.
+ * Each log record consists of a sequence number followed by the device path.
+ *
+ * When a new event is queued, its details are appended to the log.
+ * When the event finishes, a second record is appended to the log
+ * with the same sequence number but a devpath len of 0.
+ *
+ * Example:
+ *        { 0x0000000000000001 }
+ *        { 0x0000000000000001, 0x0019, "/devices/virtual/mem/null" },
+ *        { 0x0000000000000002, 0x001b, "/devices/virtual/mem/random" },
+ *        { 0x0000000000000001, 0x0000 },
+ *        { 0x0000000000000003, 0x0019, "/devices/virtual/mem/zero" },
+ *
+ * Events 2 and 3 are still queued, but event 1 has finished.
+ *
+ * The queue does not grow indefinitely. It is periodically re-created
+ * to remove finished events. Atomic rename() makes this transparent to readers.
+ *
+ * The queue file starts with a single sequence number which specifies the
+ * minimum sequence number in the log that follows. Any events prior to this
+ * sequence number have already finished.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <limits.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+static int rebuild_queue_file(struct udev_queue_export *udev_queue_export);
+
+struct udev_queue_export {
+        struct udev *udev;
+        int queued_count;        /* number of unfinished events exported in queue file */
+        FILE *queue_file;
+        unsigned long long int seqnum_max;        /* earliest sequence number in queue file */
+        unsigned long long int seqnum_min;        /* latest sequence number in queue file */
+        int waste_bytes;                        /* queue file bytes wasted on finished events */
+};
+
+struct udev_queue_export *udev_queue_export_new(struct udev *udev)
+{
+        struct udev_queue_export *udev_queue_export;
+        unsigned long long int initial_seqnum;
+
+        if (udev == NULL)
+                return NULL;
+
+        udev_queue_export = calloc(1, sizeof(struct udev_queue_export));
+        if (udev_queue_export == NULL)
+                return NULL;
+        udev_queue_export->udev = udev;
+
+        initial_seqnum = udev_get_kernel_seqnum(udev);
+        udev_queue_export->seqnum_min = initial_seqnum;
+        udev_queue_export->seqnum_max = initial_seqnum;
+
+        udev_queue_export_cleanup(udev_queue_export);
+        if (rebuild_queue_file(udev_queue_export) != 0) {
+                free(udev_queue_export);
+                return NULL;
+        }
+
+        return udev_queue_export;
+}
+
+struct udev_queue_export *udev_queue_export_unref(struct udev_queue_export *udev_queue_export)
+{
+        if (udev_queue_export == NULL)
+                return NULL;
+        if (udev_queue_export->queue_file != NULL)
+                fclose(udev_queue_export->queue_file);
+        free(udev_queue_export);
+        return NULL;
+}
+
+void udev_queue_export_cleanup(struct udev_queue_export *udev_queue_export)
+{
+        if (udev_queue_export == NULL)
+                return;
+        unlink("/run/udev/queue.tmp");
+        unlink("/run/udev/queue.bin");
+}
+
+static int skip_to(FILE *file, long offset)
+{
+        long old_offset;
+
+        /* fseek may drop buffered data, avoid it for small seeks */
+        old_offset = ftell(file);
+        if (offset > old_offset && offset - old_offset <= BUFSIZ) {
+                size_t skip_bytes = offset - old_offset;
+                char *buf = alloca(skip_bytes);
+
+                if (fread(buf, skip_bytes, 1, file) != skip_bytes)
+                        return -1;
+        }
+
+        return fseek(file, offset, SEEK_SET);
+}
+
+struct queue_devpaths {
+        unsigned int devpaths_first;        /* index of first queued event */
+        unsigned int devpaths_size;
+        long devpaths[];                /* seqnum -> offset of devpath in queue file (or 0) */
+};
+
+/*
+ * Returns a table mapping seqnum to devpath file offset for currently queued events.
+ * devpaths[i] represents the event with seqnum = i + udev_queue_export->seqnum_min.
+ */
+static struct queue_devpaths *build_index(struct udev_queue_export *udev_queue_export)
+{
+        struct queue_devpaths *devpaths;
+        unsigned long long int range;
+        long devpath_offset;
+        ssize_t devpath_len;
+        unsigned long long int seqnum;
+        unsigned long long int n;
+        unsigned int i;
+
+        /* seek to the first event in the file */
+        rewind(udev_queue_export->queue_file);
+        udev_queue_read_seqnum(udev_queue_export->queue_file, &seqnum);
+
+        /* allocate the table */
+        range = udev_queue_export->seqnum_min - udev_queue_export->seqnum_max;
+        if (range - 1 > INT_MAX) {
+                udev_err(udev_queue_export->udev, "queue file overflow\n");
+                return NULL;
+        }
+        devpaths = calloc(1, sizeof(struct queue_devpaths) + (range + 1) * sizeof(long));
+        if (devpaths == NULL)
+                return NULL;
+        devpaths->devpaths_size = range + 1;
+
+        /* read all records and populate the table */
+        for (;;) {
+                if (udev_queue_read_seqnum(udev_queue_export->queue_file, &seqnum) < 0)
+                        break;
+                n = seqnum - udev_queue_export->seqnum_max;
+                if (n >= devpaths->devpaths_size)
+                        goto read_error;
+
+                devpath_offset = ftell(udev_queue_export->queue_file);
+                devpath_len = udev_queue_skip_devpath(udev_queue_export->queue_file);
+                if (devpath_len < 0)
+                        goto read_error;
+
+                if (devpath_len > 0)
+                        devpaths->devpaths[n] = devpath_offset;
+                else
+                        devpaths->devpaths[n] = 0;
+        }
+
+        /* find first queued event */
+        for (i = 0; i < devpaths->devpaths_size; i++) {
+                if (devpaths->devpaths[i] != 0)
+                        break;
+        }
+        devpaths->devpaths_first = i;
+
+        return devpaths;
+
+read_error:
+        udev_err(udev_queue_export->udev, "queue file corrupted\n");
+        free(devpaths);
+        return NULL;
+}
+
+static int rebuild_queue_file(struct udev_queue_export *udev_queue_export)
+{
+        unsigned long long int seqnum;
+        struct queue_devpaths *devpaths = NULL;
+        FILE *new_queue_file = NULL;
+        unsigned int i;
+
+        /* read old queue file */
+        if (udev_queue_export->queue_file != NULL) {
+                devpaths = build_index(udev_queue_export);
+                if (devpaths != NULL)
+                        udev_queue_export->seqnum_max += devpaths->devpaths_first;
+        }
+        if (devpaths == NULL) {
+                udev_queue_export->queued_count = 0;
+                udev_queue_export->seqnum_max = udev_queue_export->seqnum_min;
+        }
+
+        /* create new queue file */
+        new_queue_file = fopen("/run/udev/queue.tmp", "w+e");
+        if (new_queue_file == NULL)
+                goto error;
+        seqnum = udev_queue_export->seqnum_max;
+        fwrite(&seqnum, 1, sizeof(unsigned long long int), new_queue_file);
+
+        /* copy unfinished events only to the new file */
+        if (devpaths != NULL) {
+                for (i = devpaths->devpaths_first; i < devpaths->devpaths_size; i++) {
+                        char devpath[UTIL_PATH_SIZE];
+                        int err;
+                        unsigned short devpath_len;
+
+                        if (devpaths->devpaths[i] != 0)
+                        {
+                                skip_to(udev_queue_export->queue_file, devpaths->devpaths[i]);
+                                err = udev_queue_read_devpath(udev_queue_export->queue_file, devpath, sizeof(devpath));
+                                devpath_len = err;
+
+                                fwrite(&seqnum, sizeof(unsigned long long int), 1, new_queue_file);
+                                fwrite(&devpath_len, sizeof(unsigned short), 1, new_queue_file);
+                                fwrite(devpath, 1, devpath_len, new_queue_file);
+                        }
+                        seqnum++;
+                }
+                free(devpaths);
+                devpaths = NULL;
+        }
+        fflush(new_queue_file);
+        if (ferror(new_queue_file))
+                goto error;
+
+        /* rename the new file on top of the old one */
+        if (rename("/run/udev/queue.tmp", "/run/udev/queue.bin") != 0)
+                goto error;
+
+        if (udev_queue_export->queue_file != NULL)
+                fclose(udev_queue_export->queue_file);
+        udev_queue_export->queue_file = new_queue_file;
+        udev_queue_export->waste_bytes = 0;
+
+        return 0;
+
+error:
+        udev_err(udev_queue_export->udev, "failed to create queue file: %m\n");
+        udev_queue_export_cleanup(udev_queue_export);
+
+        if (udev_queue_export->queue_file != NULL) {
+                fclose(udev_queue_export->queue_file);
+                udev_queue_export->queue_file = NULL;
+        }
+        if (new_queue_file != NULL)
+                fclose(new_queue_file);
+
+        if (devpaths != NULL)
+                free(devpaths);
+        udev_queue_export->queued_count = 0;
+        udev_queue_export->waste_bytes = 0;
+        udev_queue_export->seqnum_max = udev_queue_export->seqnum_min;
+
+        return -1;
+}
+
+static int write_queue_record(struct udev_queue_export *udev_queue_export,
+                              unsigned long long int seqnum, const char *devpath, size_t devpath_len)
+{
+        unsigned short len;
+
+        if (udev_queue_export->queue_file == NULL)
+                return -1;
+
+        if (fwrite(&seqnum, sizeof(unsigned long long int), 1, udev_queue_export->queue_file) != 1)
+                goto write_error;
+
+        len = (devpath_len < USHRT_MAX) ? devpath_len : USHRT_MAX;
+        if (fwrite(&len, sizeof(unsigned short), 1, udev_queue_export->queue_file) != 1)
+                goto write_error;
+        if (len > 0) {
+                if (fwrite(devpath, 1, len, udev_queue_export->queue_file) != len)
+                        goto write_error;
+        }
+
+        /* *must* flush output; caller may fork */
+        if (fflush(udev_queue_export->queue_file) != 0)
+                goto write_error;
+
+        return 0;
+
+write_error:
+        /* if we failed half way through writing a record to a file,
+           we should not try to write any further records to it. */
+        udev_err(udev_queue_export->udev, "error writing to queue file: %m\n");
+        fclose(udev_queue_export->queue_file);
+        udev_queue_export->queue_file = NULL;
+
+        return -1;
+}
+
+enum device_state {
+        DEVICE_QUEUED,
+        DEVICE_FINISHED,
+};
+
+static inline size_t queue_record_size(size_t devpath_len)
+{
+        return sizeof(unsigned long long int) + sizeof(unsigned short int) + devpath_len;
+}
+
+static int update_queue(struct udev_queue_export *udev_queue_export,
+                         struct udev_device *udev_device, enum device_state state)
+{
+        unsigned long long int seqnum = udev_device_get_seqnum(udev_device);
+        const char *devpath = NULL;
+        size_t devpath_len = 0;
+        int bytes;
+        int err;
+
+        /* FINISHED records have a zero length devpath */
+        if (state == DEVICE_QUEUED) {
+                devpath = udev_device_get_devpath(udev_device);
+                devpath_len = strlen(devpath);
+        }
+
+        /* recover from an earlier failed rebuild */
+        if (udev_queue_export->queue_file == NULL) {
+                if (rebuild_queue_file(udev_queue_export) != 0)
+                        return -1;
+        }
+
+        /* if we're removing the last event from the queue, that's the best time to rebuild it */
+        if (state != DEVICE_QUEUED && udev_queue_export->queued_count == 1) {
+                /* we don't need to read the old queue file */
+                fclose(udev_queue_export->queue_file);
+                udev_queue_export->queue_file = NULL;
+                rebuild_queue_file(udev_queue_export);
+                return 0;
+        }
+
+        /* try to rebuild the queue files before they grow larger than one page. */
+        bytes = ftell(udev_queue_export->queue_file) + queue_record_size(devpath_len);
+        if ((udev_queue_export->waste_bytes > bytes / 2) && bytes > 4096)
+                rebuild_queue_file(udev_queue_export);
+
+        /* don't record a finished event, if we already dropped the event in a failed rebuild */
+        if (seqnum < udev_queue_export->seqnum_max)
+                return 0;
+
+        /* now write to the queue */
+        if (state == DEVICE_QUEUED) {
+                udev_queue_export->queued_count++;
+                udev_queue_export->seqnum_min = seqnum;
+        } else {
+                udev_queue_export->waste_bytes += queue_record_size(devpath_len) + queue_record_size(0);
+                udev_queue_export->queued_count--;
+        }
+        err = write_queue_record(udev_queue_export, seqnum, devpath, devpath_len);
+
+        /* try to handle ENOSPC */
+        if (err != 0 && udev_queue_export->queued_count == 0) {
+                udev_queue_export_cleanup(udev_queue_export);
+                err = rebuild_queue_file(udev_queue_export);
+        }
+
+        return err;
+}
+
+static int update(struct udev_queue_export *udev_queue_export,
+                  struct udev_device *udev_device, enum device_state state)
+{
+        if (update_queue(udev_queue_export, udev_device, state) != 0)
+                return -1;
+
+        return 0;
+}
+
+int udev_queue_export_device_queued(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device)
+{
+        return update(udev_queue_export, udev_device, DEVICE_QUEUED);
+}
+
+int udev_queue_export_device_finished(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device)
+{
+        return update(udev_queue_export, udev_device, DEVICE_FINISHED);
+}
diff --git a/src/libudev/libudev-queue.c b/src/libudev/libudev-queue.c
new file mode 100644
index 0000000000..08d52ab1f1
--- /dev/null
+++ b/src/libudev/libudev-queue.c
@@ -0,0 +1,480 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+  Copyright 2009 Alan Jenkins <alan-jenkins@tuffmail.co.uk>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <sys/stat.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+/**
+ * SECTION:libudev-queue
+ * @short_description: access to currently active events
+ *
+ * The udev daemon processes events asynchronously. All events which do not have
+ * interdependencies run in parallel. This exports the current state of the
+ * event processing queue, and the current event sequence numbers from the kernel
+ * and the udev daemon.
+ */
+
+/**
+ * udev_queue:
+ *
+ * Opaque object representing the current event queue in the udev daemon.
+ */
+struct udev_queue {
+        struct udev *udev;
+        int refcount;
+        struct udev_list queue_list;
+};
+
+/**
+ * udev_queue_new:
+ * @udev: udev library context
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev queue context.
+ *
+ * Returns: the udev queue context, or #NULL on error.
+ **/
+_public_ struct udev_queue *udev_queue_new(struct udev *udev)
+{
+        struct udev_queue *udev_queue;
+
+        if (udev == NULL)
+                return NULL;
+
+        udev_queue = calloc(1, sizeof(struct udev_queue));
+        if (udev_queue == NULL)
+                return NULL;
+        udev_queue->refcount = 1;
+        udev_queue->udev = udev;
+        udev_list_init(udev, &udev_queue->queue_list, false);
+        return udev_queue;
+}
+
+/**
+ * udev_queue_ref:
+ * @udev_queue: udev queue context
+ *
+ * Take a reference of a udev queue context.
+ *
+ * Returns: the same udev queue context.
+ **/
+_public_ struct udev_queue *udev_queue_ref(struct udev_queue *udev_queue)
+{
+        if (udev_queue == NULL)
+                return NULL;
+        udev_queue->refcount++;
+        return udev_queue;
+}
+
+/**
+ * udev_queue_unref:
+ * @udev_queue: udev queue context
+ *
+ * Drop a reference of a udev queue context. If the refcount reaches zero,
+ * the resources of the queue context will be released.
+ *
+ * Returns: the passed queue context if it has still an active reference, or #NULL otherwise.
+ **/
+_public_ struct udev_queue *udev_queue_unref(struct udev_queue *udev_queue)
+{
+        if (udev_queue == NULL)
+                return NULL;
+        udev_queue->refcount--;
+        if (udev_queue->refcount > 0)
+                return udev_queue;
+        udev_list_cleanup(&udev_queue->queue_list);
+        free(udev_queue);
+        return NULL;
+}
+
+/**
+ * udev_queue_get_udev:
+ * @udev_queue: udev queue context
+ *
+ * Retrieve the udev library context the queue context was created with.
+ *
+ * Returns: the udev library context.
+ **/
+_public_ struct udev *udev_queue_get_udev(struct udev_queue *udev_queue)
+{
+        if (udev_queue == NULL)
+                return NULL;
+        return udev_queue->udev;
+}
+
+unsigned long long int udev_get_kernel_seqnum(struct udev *udev)
+{
+        unsigned long long int seqnum;
+        int fd;
+        char buf[32];
+        ssize_t len;
+
+        fd = open("/sys/kernel/uevent_seqnum", O_RDONLY|O_CLOEXEC);
+        if (fd < 0)
+                return 0;
+        len = read(fd, buf, sizeof(buf));
+        close(fd);
+        if (len <= 2)
+                return 0;
+        buf[len-1] = '\0';
+        seqnum = strtoull(buf, NULL, 10);
+        return seqnum;
+}
+
+/**
+ * udev_queue_get_kernel_seqnum:
+ * @udev_queue: udev queue context
+ *
+ * Get the current kernel event sequence number.
+ *
+ * Returns: the sequence number.
+ **/
+_public_ unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queue)
+{
+        unsigned long long int seqnum;
+
+        if (udev_queue == NULL)
+                return -EINVAL;
+
+        seqnum = udev_get_kernel_seqnum(udev_queue->udev);
+        return seqnum;
+}
+
+int udev_queue_read_seqnum(FILE *queue_file, unsigned long long int *seqnum)
+{
+        if (fread(seqnum, sizeof(unsigned long long int), 1, queue_file) != 1)
+                return -1;
+
+        return 0;
+}
+
+ssize_t udev_queue_skip_devpath(FILE *queue_file)
+{
+        unsigned short int len;
+
+        if (fread(&len, sizeof(unsigned short int), 1, queue_file) == 1) {
+                char *devpath = alloca(len);
+
+                /* use fread to skip, fseek might drop buffered data */
+                if (fread(devpath, 1, len, queue_file) == len)
+                        return len;
+        }
+
+        return -1;
+}
+
+ssize_t udev_queue_read_devpath(FILE *queue_file, char *devpath, size_t size)
+{
+        unsigned short int read_bytes = 0;
+        unsigned short int len;
+
+        if (fread(&len, sizeof(unsigned short int), 1, queue_file) != 1)
+                return -1;
+
+        read_bytes = (len < size - 1) ? len : size - 1;
+        if (fread(devpath, 1, read_bytes, queue_file) != read_bytes)
+                return -1;
+        devpath[read_bytes] = '\0';
+
+        /* if devpath was too long, skip unread characters */
+        if (read_bytes != len) {
+                unsigned short int skip_bytes = len - read_bytes;
+                char *buf = alloca(skip_bytes);
+
+                if (fread(buf, 1, skip_bytes, queue_file) != skip_bytes)
+                        return -1;
+        }
+
+        return read_bytes;
+}
+
+static FILE *open_queue_file(struct udev_queue *udev_queue, unsigned long long int *seqnum_start)
+{
+        FILE *queue_file;
+
+        queue_file = fopen("/run/udev/queue.bin", "re");
+        if (queue_file == NULL)
+                return NULL;
+
+        if (udev_queue_read_seqnum(queue_file, seqnum_start) < 0) {
+                udev_err(udev_queue->udev, "corrupt queue file\n");
+                fclose(queue_file);
+                return NULL;
+        }
+
+        return queue_file;
+}
+
+/**
+ * udev_queue_get_udev_seqnum:
+ * @udev_queue: udev queue context
+ *
+ * Get the last known udev event sequence number.
+ *
+ * Returns: the sequence number.
+ **/
+_public_ unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue)
+{
+        unsigned long long int seqnum_udev;
+        FILE *queue_file;
+
+        queue_file = open_queue_file(udev_queue, &seqnum_udev);
+        if (queue_file == NULL)
+                return 0;
+
+        for (;;) {
+                unsigned long long int seqnum;
+                ssize_t devpath_len;
+
+                if (udev_queue_read_seqnum(queue_file, &seqnum) < 0)
+                        break;
+                devpath_len = udev_queue_skip_devpath(queue_file);
+                if (devpath_len < 0)
+                        break;
+                if (devpath_len > 0)
+                        seqnum_udev = seqnum;
+        }
+
+        fclose(queue_file);
+        return seqnum_udev;
+}
+
+/**
+ * udev_queue_get_udev_is_active:
+ * @udev_queue: udev queue context
+ *
+ * Check if udev is active on the system.
+ *
+ * Returns: a flag indicating if udev is active.
+ **/
+_public_ int udev_queue_get_udev_is_active(struct udev_queue *udev_queue)
+{
+        unsigned long long int seqnum_start;
+        FILE *queue_file;
+
+        queue_file = open_queue_file(udev_queue, &seqnum_start);
+        if (queue_file == NULL)
+                return 0;
+
+        fclose(queue_file);
+        return 1;
+}
+
+/**
+ * udev_queue_get_queue_is_empty:
+ * @udev_queue: udev queue context
+ *
+ * Check if udev is currently processing any events.
+ *
+ * Returns: a flag indicating if udev is currently handling events.
+ **/
+_public_ int udev_queue_get_queue_is_empty(struct udev_queue *udev_queue)
+{
+        unsigned long long int seqnum_kernel;
+        unsigned long long int seqnum_udev = 0;
+        int queued = 0;
+        int is_empty = 0;
+        FILE *queue_file;
+
+        if (udev_queue == NULL)
+                return -EINVAL;
+        queue_file = open_queue_file(udev_queue, &seqnum_udev);
+        if (queue_file == NULL)
+                return 1;
+
+        for (;;) {
+                unsigned long long int seqnum;
+                ssize_t devpath_len;
+
+                if (udev_queue_read_seqnum(queue_file, &seqnum) < 0)
+                        break;
+                devpath_len = udev_queue_skip_devpath(queue_file);
+                if (devpath_len < 0)
+                        break;
+
+                if (devpath_len > 0) {
+                        queued++;
+                        seqnum_udev = seqnum;
+                } else {
+                        queued--;
+                }
+        }
+
+        if (queued > 0)
+                goto out;
+
+        seqnum_kernel = udev_queue_get_kernel_seqnum(udev_queue);
+        if (seqnum_udev < seqnum_kernel)
+                goto out;
+
+        is_empty = 1;
+
+out:
+        fclose(queue_file);
+        return is_empty;
+}
+
+/**
+ * udev_queue_get_seqnum_sequence_is_finished:
+ * @udev_queue: udev queue context
+ * @start: first event sequence number
+ * @end: last event sequence number
+ *
+ * Check if udev is currently processing any events in a given sequence number range.
+ *
+ * Returns: a flag indicating if any of the sequence numbers in the given range is currently active.
+ **/
+_public_ int udev_queue_get_seqnum_sequence_is_finished(struct udev_queue *udev_queue,
+                                               unsigned long long int start, unsigned long long int end)
+{
+        unsigned long long int seqnum;
+        ssize_t devpath_len;
+        int unfinished;
+        FILE *queue_file;
+
+        if (udev_queue == NULL)
+                return -EINVAL;
+        queue_file = open_queue_file(udev_queue, &seqnum);
+        if (queue_file == NULL)
+                return 1;
+        if (start < seqnum)
+                start = seqnum;
+        if (start > end) {
+                fclose(queue_file);
+                return 1;
+        }
+        if (end - start > INT_MAX - 1) {
+                fclose(queue_file);
+                return -EOVERFLOW;
+        }
+
+        /*
+         * we might start with 0, and handle the initial seqnum
+         * only when we find an entry in the queue file
+         **/
+        unfinished = end - start;
+
+        do {
+                if (udev_queue_read_seqnum(queue_file, &seqnum) < 0)
+                        break;
+                devpath_len = udev_queue_skip_devpath(queue_file);
+                if (devpath_len < 0)
+                        break;
+
+                /*
+                 * we might start with an empty or re-build queue file, where
+                 * the initial seqnum is not recorded as finished
+                 */
+                if (start == seqnum && devpath_len > 0)
+                        unfinished++;
+
+                if (devpath_len == 0) {
+                        if (seqnum >= start && seqnum <= end)
+                                unfinished--;
+                }
+        } while (unfinished > 0);
+
+        fclose(queue_file);
+
+        return (unfinished == 0);
+}
+
+/**
+ * udev_queue_get_seqnum_is_finished:
+ * @udev_queue: udev queue context
+ * @seqnum: sequence number
+ *
+ * Check if udev is currently processing a given sequence number.
+ *
+ * Returns: a flag indicating if the given sequence number is currently active.
+ **/
+_public_ int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum)
+{
+        if (!udev_queue_get_seqnum_sequence_is_finished(udev_queue, seqnum, seqnum))
+                return 0;
+
+        return 1;
+}
+
+/**
+ * udev_queue_get_queued_list_entry:
+ * @udev_queue: udev queue context
+ *
+ * Get the first entry of the list of queued events.
+ *
+ * Returns: a udev_list_entry.
+ **/
+_public_ struct udev_list_entry *udev_queue_get_queued_list_entry(struct udev_queue *udev_queue)
+{
+        unsigned long long int seqnum;
+        FILE *queue_file;
+
+        if (udev_queue == NULL)
+                return NULL;
+        udev_list_cleanup(&udev_queue->queue_list);
+
+        queue_file = open_queue_file(udev_queue, &seqnum);
+        if (queue_file == NULL)
+                return NULL;
+
+        for (;;) {
+                char syspath[UTIL_PATH_SIZE];
+                char *s;
+                size_t l;
+                ssize_t len;
+                char seqnum_str[32];
+                struct udev_list_entry *list_entry;
+
+                if (udev_queue_read_seqnum(queue_file, &seqnum) < 0)
+                        break;
+                snprintf(seqnum_str, sizeof(seqnum_str), "%llu", seqnum);
+
+                s = syspath;
+                l = util_strpcpy(&s, sizeof(syspath), "/sys");
+                len = udev_queue_read_devpath(queue_file, s, l);
+                if (len < 0)
+                        break;
+
+                if (len > 0) {
+                        udev_list_entry_add(&udev_queue->queue_list, syspath, seqnum_str);
+                } else {
+                        udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_queue->queue_list)) {
+                                if (strcmp(seqnum_str, udev_list_entry_get_value(list_entry)) == 0) {
+                                        udev_list_entry_delete(list_entry);
+                                        break;
+                                }
+                        }
+                }
+        }
+        fclose(queue_file);
+
+        return udev_list_get_entry(&udev_queue->queue_list);
+}
diff --git a/src/libudev/libudev-util.c b/src/libudev/libudev-util.c
new file mode 100644
index 0000000000..cb9ed9c84b
--- /dev/null
+++ b/src/libudev/libudev-util.c
@@ -0,0 +1,725 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <dirent.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <time.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/stat.h>
+#include <sys/param.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+/**
+ * SECTION:libudev-util
+ * @short_description: utils
+ *
+ * Utilities useful when dealing with devices and device node names.
+ */
+
+int util_delete_path(struct udev *udev, const char *path)
+{
+        char p[UTIL_PATH_SIZE];
+        char *pos;
+        int err = 0;
+
+        if (path[0] == '/')
+                while(path[1] == '/')
+                        path++;
+        util_strscpy(p, sizeof(p), path);
+        pos = strrchr(p, '/');
+        if (pos == p || pos == NULL)
+                return 0;
+
+        for (;;) {
+                *pos = '\0';
+                pos = strrchr(p, '/');
+
+                /* don't remove the last one */
+                if ((pos == p) || (pos == NULL))
+                        break;
+
+                err = rmdir(p);
+                if (err < 0) {
+                        if (errno == ENOENT)
+                                err = 0;
+                        break;
+                }
+        }
+        return err;
+}
+
+uid_t util_lookup_user(struct udev *udev, const char *user)
+{
+        char *endptr;
+        struct passwd pwbuf;
+        struct passwd *pw;
+        uid_t uid;
+        size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+        char *buf = alloca(buflen);
+
+        if (strcmp(user, "root") == 0)
+                return 0;
+        uid = strtoul(user, &endptr, 10);
+        if (endptr[0] == '\0')
+                return uid;
+
+        errno = getpwnam_r(user, &pwbuf, buf, buflen, &pw);
+        if (pw != NULL)
+                return pw->pw_uid;
+        if (errno == 0 || errno == ENOENT || errno == ESRCH)
+                udev_err(udev, "specified user '%s' unknown\n", user);
+        else
+                udev_err(udev, "error resolving user '%s': %m\n", user);
+        return 0;
+}
+
+gid_t util_lookup_group(struct udev *udev, const char *group)
+{
+        char *endptr;
+        struct group grbuf;
+        struct group *gr;
+        gid_t gid = 0;
+        size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+        char *buf = NULL;
+
+        if (strcmp(group, "root") == 0)
+                return 0;
+        gid = strtoul(group, &endptr, 10);
+        if (endptr[0] == '\0')
+                return gid;
+        gid = 0;
+        for (;;) {
+                char *newbuf;
+
+                newbuf = realloc(buf, buflen);
+                if (!newbuf)
+                        break;
+                buf = newbuf;
+                errno = getgrnam_r(group, &grbuf, buf, buflen, &gr);
+                if (gr != NULL) {
+                        gid = gr->gr_gid;
+                } else if (errno == ERANGE) {
+                        buflen *= 2;
+                        continue;
+                } else if (errno == 0 || errno == ENOENT || errno == ESRCH) {
+                        udev_err(udev, "specified group '%s' unknown\n", group);
+                } else {
+                        udev_err(udev, "error resolving group '%s': %m\n", group);
+                }
+                break;
+        }
+        free(buf);
+        return gid;
+}
+
+/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
+int util_resolve_subsys_kernel(struct udev *udev, const char *string,
+                               char *result, size_t maxsize, int read_value)
+{
+        char temp[UTIL_PATH_SIZE];
+        char *subsys;
+        char *sysname;
+        struct udev_device *dev;
+        char *attr;
+
+        if (string[0] != '[')
+                return -1;
+
+        util_strscpy(temp, sizeof(temp), string);
+
+        subsys = &temp[1];
+
+        sysname = strchr(subsys, '/');
+        if (sysname == NULL)
+                return -1;
+        sysname[0] = '\0';
+        sysname = &sysname[1];
+
+        attr = strchr(sysname, ']');
+        if (attr == NULL)
+                return -1;
+        attr[0] = '\0';
+        attr = &attr[1];
+        if (attr[0] == '/')
+                attr = &attr[1];
+        if (attr[0] == '\0')
+                attr = NULL;
+
+        if (read_value && attr == NULL)
+                return -1;
+
+        dev = udev_device_new_from_subsystem_sysname(udev, subsys, sysname);
+        if (dev == NULL)
+                return -1;
+
+        if (read_value) {
+                const char *val;
+
+                val = udev_device_get_sysattr_value(dev, attr);
+                if (val != NULL)
+                        util_strscpy(result, maxsize, val);
+                else
+                        result[0] = '\0';
+                udev_dbg(udev, "value '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
+        } else {
+                size_t l;
+                char *s;
+
+                s = result;
+                l = util_strpcpyl(&s, maxsize, udev_device_get_syspath(dev), NULL);
+                if (attr != NULL)
+                        util_strpcpyl(&s, l, "/", attr, NULL);
+                udev_dbg(udev, "path '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result);
+        }
+        udev_device_unref(dev);
+        return 0;
+}
+ssize_t util_get_sys_core_link_value(struct udev *udev, const char *slink, const char *syspath, char *value, size_t size)
+{
+        char path[UTIL_PATH_SIZE];
+        char target[UTIL_PATH_SIZE];
+        ssize_t len;
+        const char *pos;
+
+        util_strscpyl(path, sizeof(path), syspath, "/", slink, NULL);
+        len = readlink(path, target, sizeof(target));
+        if (len <= 0 || len == (ssize_t)sizeof(target))
+                return -1;
+        target[len] = '\0';
+        pos = strrchr(target, '/');
+        if (pos == NULL)
+                return -1;
+        pos = &pos[1];
+        return util_strscpy(value, size, pos);
+}
+
+int util_resolve_sys_link(struct udev *udev, char *syspath, size_t size)
+{
+        char link_target[UTIL_PATH_SIZE];
+
+        ssize_t len;
+        int i;
+        int back;
+        char *base = NULL;
+
+        len = readlink(syspath, link_target, sizeof(link_target));
+        if (len <= 0 || len == (ssize_t)sizeof(link_target))
+                return -1;
+        link_target[len] = '\0';
+
+        for (back = 0; startswith(&link_target[back * 3], "../"); back++)
+                ;
+        for (i = 0; i <= back; i++) {
+                base = strrchr(syspath, '/');
+                if (base == NULL)
+                        return -EINVAL;
+                base[0] = '\0';
+        }
+        if (base == NULL)
+                return -EINVAL;
+        util_strscpyl(base, size - (base - syspath), "/", &link_target[back * 3], NULL);
+        return 0;
+}
+
+int util_log_priority(const char *priority)
+{
+        char *endptr;
+        int prio;
+
+        prio = strtol(priority, &endptr, 10);
+        if (endptr[0] == '\0' || isspace(endptr[0]))
+                return prio;
+        if (startswith(priority, "err"))
+                return LOG_ERR;
+        if (startswith(priority, "info"))
+                return LOG_INFO;
+        if (startswith(priority, "debug"))
+                return LOG_DEBUG;
+        return 0;
+}
+
+size_t util_path_encode(const char *src, char *dest, size_t size)
+{
+        size_t i, j;
+
+        for (i = 0, j = 0; src[i] != '\0'; i++) {
+                if (src[i] == '/') {
+                        if (j+4 >= size) {
+                                j = 0;
+                                break;
+                        }
+                        memcpy(&dest[j], "\\x2f", 4);
+                        j += 4;
+                } else if (src[i] == '\\') {
+                        if (j+4 >= size) {
+                                j = 0;
+                                break;
+                        }
+                        memcpy(&dest[j], "\\x5c", 4);
+                        j += 4;
+                } else {
+                        if (j+1 >= size) {
+                                j = 0;
+                                break;
+                        }
+                        dest[j] = src[i];
+                        j++;
+                }
+        }
+        dest[j] = '\0';
+        return j;
+}
+
+void util_remove_trailing_chars(char *path, char c)
+{
+        size_t len;
+
+        if (path == NULL)
+                return;
+        len = strlen(path);
+        while (len > 0 && path[len-1] == c)
+                path[--len] = '\0';
+}
+
+/*
+ * Concatenates strings. In any case, terminates in _all_ cases with '\0'
+ * and moves the @dest pointer forward to the added '\0'. Returns the
+ * remaining size, and 0 if the string was truncated.
+ */
+size_t util_strpcpy(char **dest, size_t size, const char *src)
+{
+        size_t len;
+
+        len = strlen(src);
+        if (len >= size) {
+                if (size > 1)
+                        *dest = mempcpy(*dest, src, size-1);
+                size = 0;
+                *dest[0] = '\0';
+        } else {
+                if (len > 0) {
+                        *dest = mempcpy(*dest, src, len);
+                        size -= len;
+                }
+                *dest[0] = '\0';
+        }
+        return size;
+}
+
+/* concatenates list of strings, moves dest forward */
+size_t util_strpcpyl(char **dest, size_t size, const char *src, ...)
+{
+        va_list va;
+
+        va_start(va, src);
+        do {
+                size = util_strpcpy(dest, size, src);
+                src = va_arg(va, char *);
+        } while (src != NULL);
+        va_end(va);
+
+        return size;
+}
+
+/* copies string */
+size_t util_strscpy(char *dest, size_t size, const char *src)
+{
+        char *s;
+
+        s = dest;
+        return util_strpcpy(&s, size, src);
+}
+
+/* concatenates list of strings */
+size_t util_strscpyl(char *dest, size_t size, const char *src, ...)
+{
+        va_list va;
+        char *s;
+
+        va_start(va, src);
+        s = dest;
+        do {
+                size = util_strpcpy(&s, size, src);
+                src = va_arg(va, char *);
+        } while (src != NULL);
+        va_end(va);
+
+        return size;
+}
+
+/* count of characters used to encode one unicode char */
+static int utf8_encoded_expected_len(const char *str)
+{
+        unsigned char c = (unsigned char)str[0];
+
+        if (c < 0x80)
+                return 1;
+        if ((c & 0xe0) == 0xc0)
+                return 2;
+        if ((c & 0xf0) == 0xe0)
+                return 3;
+        if ((c & 0xf8) == 0xf0)
+                return 4;
+        if ((c & 0xfc) == 0xf8)
+                return 5;
+        if ((c & 0xfe) == 0xfc)
+                return 6;
+        return 0;
+}
+
+/* decode one unicode char */
+static int utf8_encoded_to_unichar(const char *str)
+{
+        int unichar;
+        int len;
+        int i;
+
+        len = utf8_encoded_expected_len(str);
+        switch (len) {
+        case 1:
+                return (int)str[0];
+        case 2:
+                unichar = str[0] & 0x1f;
+                break;
+        case 3:
+                unichar = (int)str[0] & 0x0f;
+                break;
+        case 4:
+                unichar = (int)str[0] & 0x07;
+                break;
+        case 5:
+                unichar = (int)str[0] & 0x03;
+                break;
+        case 6:
+                unichar = (int)str[0] & 0x01;
+                break;
+        default:
+                return -1;
+        }
+
+        for (i = 1; i < len; i++) {
+                if (((int)str[i] & 0xc0) != 0x80)
+                        return -1;
+                unichar <<= 6;
+                unichar |= (int)str[i] & 0x3f;
+        }
+
+        return unichar;
+}
+
+/* expected size used to encode one unicode char */
+static int utf8_unichar_to_encoded_len(int unichar)
+{
+        if (unichar < 0x80)
+                return 1;
+        if (unichar < 0x800)
+                return 2;
+        if (unichar < 0x10000)
+                return 3;
+        if (unichar < 0x200000)
+                return 4;
+        if (unichar < 0x4000000)
+                return 5;
+        return 6;
+}
+
+/* check if unicode char has a valid numeric range */
+static int utf8_unichar_valid_range(int unichar)
+{
+        if (unichar > 0x10ffff)
+                return 0;
+        if ((unichar & 0xfffff800) == 0xd800)
+                return 0;
+        if ((unichar > 0xfdcf) && (unichar < 0xfdf0))
+                return 0;
+        if ((unichar & 0xffff) == 0xffff)
+                return 0;
+        return 1;
+}
+
+/* validate one encoded unicode char and return its length */
+static int utf8_encoded_valid_unichar(const char *str)
+{
+        int len;
+        int unichar;
+        int i;
+
+        len = utf8_encoded_expected_len(str);
+        if (len == 0)
+                return -1;
+
+        /* ascii is valid */
+        if (len == 1)
+                return 1;
+
+        /* check if expected encoded chars are available */
+        for (i = 0; i < len; i++)
+                if ((str[i] & 0x80) != 0x80)
+                        return -1;
+
+        unichar = utf8_encoded_to_unichar(str);
+
+        /* check if encoded length matches encoded value */
+        if (utf8_unichar_to_encoded_len(unichar) != len)
+                return -1;
+
+        /* check if value has valid range */
+        if (!utf8_unichar_valid_range(unichar))
+                return -1;
+
+        return len;
+}
+
+int util_replace_whitespace(const char *str, char *to, size_t len)
+{
+        size_t i, j;
+
+        /* strip trailing whitespace */
+        len = strnlen(str, len);
+        while (len && isspace(str[len-1]))
+                len--;
+
+        /* strip leading whitespace */
+        i = 0;
+        while (isspace(str[i]) && (i < len))
+                i++;
+
+        j = 0;
+        while (i < len) {
+                /* substitute multiple whitespace with a single '_' */
+                if (isspace(str[i])) {
+                        while (isspace(str[i]))
+                                i++;
+                        to[j++] = '_';
+                }
+                to[j++] = str[i++];
+        }
+        to[j] = '\0';
+        return 0;
+}
+
+static int is_whitelisted(char c, const char *white)
+{
+        if ((c >= '0' && c <= '9') ||
+            (c >= 'A' && c <= 'Z') ||
+            (c >= 'a' && c <= 'z') ||
+            strchr("#+-.:=@_", c) != NULL ||
+            (white != NULL && strchr(white, c) != NULL))
+                return 1;
+        return 0;
+}
+
+/* allow chars in whitelist, plain ascii, hex-escaping and valid utf8 */
+int util_replace_chars(char *str, const char *white)
+{
+        size_t i = 0;
+        int replaced = 0;
+
+        while (str[i] != '\0') {
+                int len;
+
+                if (is_whitelisted(str[i], white)) {
+                        i++;
+                        continue;
+                }
+
+                /* accept hex encoding */
+                if (str[i] == '\\' && str[i+1] == 'x') {
+                        i += 2;
+                        continue;
+                }
+
+                /* accept valid utf8 */
+                len = utf8_encoded_valid_unichar(&str[i]);
+                if (len > 1) {
+                        i += len;
+                        continue;
+                }
+
+                /* if space is allowed, replace whitespace with ordinary space */
+                if (isspace(str[i]) && white != NULL && strchr(white, ' ') != NULL) {
+                        str[i] = ' ';
+                        i++;
+                        replaced++;
+                        continue;
+                }
+
+                /* everything else is replaced with '_' */
+                str[i] = '_';
+                i++;
+                replaced++;
+        }
+        return replaced;
+}
+
+/**
+ * udev_util_encode_string:
+ * @str: input string to be encoded
+ * @str_enc: output string to store the encoded input string
+ * @len: maximum size of the output string, which may be
+ *       four times as long as the input string
+ *
+ * Encode all potentially unsafe characters of a string to the
+ * corresponding 2 char hex value prefixed by '\x'.
+ *
+ * Returns: 0 if the entire string was copied, non-zero otherwise.
+ **/
+_public_ int udev_util_encode_string(const char *str, char *str_enc, size_t len)
+{
+        size_t i, j;
+
+        if (str == NULL || str_enc == NULL)
+                return -1;
+
+        for (i = 0, j = 0; str[i] != '\0'; i++) {
+                int seqlen;
+
+                seqlen = utf8_encoded_valid_unichar(&str[i]);
+                if (seqlen > 1) {
+                        if (len-j < (size_t)seqlen)
+                                goto err;
+                        memcpy(&str_enc[j], &str[i], seqlen);
+                        j += seqlen;
+                        i += (seqlen-1);
+                } else if (str[i] == '\\' || !is_whitelisted(str[i], NULL)) {
+                        if (len-j < 4)
+                                goto err;
+                        sprintf(&str_enc[j], "\\x%02x", (unsigned char) str[i]);
+                        j += 4;
+                } else {
+                        if (len-j < 1)
+                                goto err;
+                        str_enc[j] = str[i];
+                        j++;
+                }
+        }
+        if (len-j < 1)
+                goto err;
+        str_enc[j] = '\0';
+        return 0;
+err:
+        return -1;
+}
+
+/*
+ * http://sites.google.com/site/murmurhash/
+ *
+ * All code is released to the public domain. For business purposes,
+ * Murmurhash is under the MIT license.
+ *
+ */
+static unsigned int murmur_hash2(const char *key, int len, unsigned int seed)
+{
+        /*
+         *  'm' and 'r' are mixing constants generated offline.
+         *  They're not really 'magic', they just happen to work well.
+         */
+        const unsigned int m = 0x5bd1e995;
+        const int r = 24;
+
+        /* initialize the hash to a 'random' value */
+        unsigned int h = seed ^ len;
+
+        /* mix 4 bytes at a time into the hash */
+        const unsigned char * data = (const unsigned char *)key;
+
+        while(len >= 4) {
+                unsigned int k = *(unsigned int *)data;
+
+                k *= m;
+                k ^= k >> r;
+                k *= m;
+                h *= m;
+                h ^= k;
+
+                data += 4;
+                len -= 4;
+        }
+
+        /* handle the last few bytes of the input array */
+        switch(len) {
+        case 3:
+                h ^= data[2] << 16;
+        case 2:
+                h ^= data[1] << 8;
+        case 1:
+                h ^= data[0];
+                h *= m;
+        };
+
+        /* do a few final mixes of the hash to ensure the last few bytes are well-incorporated */
+        h ^= h >> 13;
+        h *= m;
+        h ^= h >> 15;
+
+        return h;
+}
+
+unsigned int util_string_hash32(const char *str)
+{
+        return murmur_hash2(str, strlen(str), 0);
+}
+
+/* get a bunch of bit numbers out of the hash, and set the bits in our bit field */
+uint64_t util_string_bloom64(const char *str)
+{
+        uint64_t bits = 0;
+        unsigned int hash = util_string_hash32(str);
+
+        bits |= 1LLU << (hash & 63);
+        bits |= 1LLU << ((hash >> 6) & 63);
+        bits |= 1LLU << ((hash >> 12) & 63);
+        bits |= 1LLU << ((hash >> 18) & 63);
+        return bits;
+}
+
+ssize_t print_kmsg(const char *fmt, ...)
+{
+        int fd;
+        va_list ap;
+        char text[1024];
+        ssize_t len;
+        ssize_t ret;
+
+        fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                return -errno;
+
+        len = snprintf(text, sizeof(text), "<30>systemd-udevd[%u]: ", getpid());
+
+        va_start(ap, fmt);
+        len += vsnprintf(text + len, sizeof(text) - len, fmt, ap);
+        va_end(ap);
+
+        ret = write(fd, text, len);
+        if (ret < 0)
+                ret = -errno;
+        close(fd);
+        return ret;
+}
diff --git a/src/libudev/libudev.c b/src/libudev/libudev.c
new file mode 100644
index 0000000000..d860ebc080
--- /dev/null
+++ b/src/libudev/libudev.c
@@ -0,0 +1,314 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <ctype.h>
+#include <time.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+#include "missing.h"
+
+/**
+ * SECTION:libudev
+ * @short_description: libudev context
+ *
+ * The context contains the default values read from the udev config file,
+ * and is passed to all library operations.
+ */
+
+/**
+ * udev:
+ *
+ * Opaque object representing the library context.
+ */
+struct udev {
+        int refcount;
+        void (*log_fn)(struct udev *udev,
+                       int priority, const char *file, int line, const char *fn,
+                       const char *format, va_list args);
+        void *userdata;
+        struct udev_list properties_list;
+        int log_priority;
+};
+
+void udev_log(struct udev *udev,
+              int priority, const char *file, int line, const char *fn,
+              const char *format, ...)
+{
+        va_list args;
+
+        va_start(args, format);
+        udev->log_fn(udev, priority, file, line, fn, format, args);
+        va_end(args);
+}
+
+static void log_stderr(struct udev *udev,
+                       int priority, const char *file, int line, const char *fn,
+                       const char *format, va_list args)
+{
+        fprintf(stderr, "libudev: %s: ", fn);
+        vfprintf(stderr, format, args);
+}
+
+/**
+ * udev_get_userdata:
+ * @udev: udev library context
+ *
+ * Retrieve stored data pointer from library context. This might be useful
+ * to access from callbacks like a custom logging function.
+ *
+ * Returns: stored userdata
+ **/
+_public_ void *udev_get_userdata(struct udev *udev)
+{
+        if (udev == NULL)
+                return NULL;
+        return udev->userdata;
+}
+
+/**
+ * udev_set_userdata:
+ * @udev: udev library context
+ * @userdata: data pointer
+ *
+ * Store custom @userdata in the library context.
+ **/
+_public_ void udev_set_userdata(struct udev *udev, void *userdata)
+{
+        if (udev == NULL)
+                return;
+        udev->userdata = userdata;
+}
+
+/**
+ * udev_new:
+ *
+ * Create udev library context. This reads the udev configuration
+ * file, and fills in the default values.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev library context.
+ *
+ * Returns: a new udev library context
+ **/
+_public_ struct udev *udev_new(void)
+{
+        struct udev *udev;
+        const char *env;
+        FILE *f;
+
+        udev = calloc(1, sizeof(struct udev));
+        if (udev == NULL)
+                return NULL;
+        udev->refcount = 1;
+        udev->log_fn = log_stderr;
+        udev->log_priority = LOG_ERR;
+        udev_list_init(udev, &udev->properties_list, true);
+
+        f = fopen("/etc/udev/udev.conf", "re");
+        if (f != NULL) {
+                char line[UTIL_LINE_SIZE];
+                int line_nr = 0;
+
+                while (fgets(line, sizeof(line), f)) {
+                        size_t len;
+                        char *key;
+                        char *val;
+
+                        line_nr++;
+
+                        /* find key */
+                        key = line;
+                        while (isspace(key[0]))
+                                key++;
+
+                        /* comment or empty line */
+                        if (key[0] == '#' || key[0] == '\0')
+                                continue;
+
+                        /* split key/value */
+                        val = strchr(key, '=');
+                        if (val == NULL) {
+                                udev_err(udev, "missing <key>=<value> in /etc/udev/udev.conf[%i]; skip line\n", line_nr);
+                                continue;
+                        }
+                        val[0] = '\0';
+                        val++;
+
+                        /* find value */
+                        while (isspace(val[0]))
+                                val++;
+
+                        /* terminate key */
+                        len = strlen(key);
+                        if (len == 0)
+                                continue;
+                        while (isspace(key[len-1]))
+                                len--;
+                        key[len] = '\0';
+
+                        /* terminate value */
+                        len = strlen(val);
+                        if (len == 0)
+                                continue;
+                        while (isspace(val[len-1]))
+                                len--;
+                        val[len] = '\0';
+
+                        if (len == 0)
+                                continue;
+
+                        /* unquote */
+                        if (val[0] == '"' || val[0] == '\'') {
+                                if (val[len-1] != val[0]) {
+                                        udev_err(udev, "inconsistent quoting in /etc/udev/udev.conf[%i]; skip line\n", line_nr);
+                                        continue;
+                                }
+                                val[len-1] = '\0';
+                                val++;
+                        }
+
+                        if (strcmp(key, "udev_log") == 0) {
+                                udev_set_log_priority(udev, util_log_priority(val));
+                                continue;
+                        }
+                }
+                fclose(f);
+        }
+
+        /* environment overrides config */
+        env = secure_getenv("UDEV_LOG");
+        if (env != NULL)
+                udev_set_log_priority(udev, util_log_priority(env));
+
+        return udev;
+}
+
+/**
+ * udev_ref:
+ * @udev: udev library context
+ *
+ * Take a reference of the udev library context.
+ *
+ * Returns: the passed udev library context
+ **/
+_public_ struct udev *udev_ref(struct udev *udev)
+{
+        if (udev == NULL)
+                return NULL;
+        udev->refcount++;
+        return udev;
+}
+
+/**
+ * udev_unref:
+ * @udev: udev library context
+ *
+ * Drop a reference of the udev library context. If the refcount
+ * reaches zero, the resources of the context will be released.
+ *
+ * Returns: the passed udev library context if it has still an active reference, or #NULL otherwise.
+ **/
+_public_ struct udev *udev_unref(struct udev *udev)
+{
+        if (udev == NULL)
+                return NULL;
+        udev->refcount--;
+        if (udev->refcount > 0)
+                return udev;
+        udev_list_cleanup(&udev->properties_list);
+        free(udev);
+        return NULL;
+}
+
+/**
+ * udev_set_log_fn:
+ * @udev: udev library context
+ * @log_fn: function to be called for logging messages
+ *
+ * The built-in logging writes to stderr. It can be
+ * overridden by a custom function, to plug log messages
+ * into the users' logging functionality.
+ *
+ **/
+_public_ void udev_set_log_fn(struct udev *udev,
+                     void (*log_fn)(struct udev *udev,
+                                    int priority, const char *file, int line, const char *fn,
+                                    const char *format, va_list args))
+{
+        udev->log_fn = log_fn;
+        udev_dbg(udev, "custom logging function %p registered\n", log_fn);
+}
+
+/**
+ * udev_get_log_priority:
+ * @udev: udev library context
+ *
+ * The initial logging priority is read from the udev config file
+ * at startup.
+ *
+ * Returns: the current logging priority
+ **/
+_public_ int udev_get_log_priority(struct udev *udev)
+{
+        return udev->log_priority;
+}
+
+/**
+ * udev_set_log_priority:
+ * @udev: udev library context
+ * @priority: the new logging priority
+ *
+ * Set the current logging priority. The value controls which messages
+ * are logged.
+ **/
+_public_ void udev_set_log_priority(struct udev *udev, int priority)
+{
+        char num[32];
+
+        udev->log_priority = priority;
+        snprintf(num, sizeof(num), "%u", udev->log_priority);
+        udev_add_property(udev, "UDEV_LOG", num);
+}
+
+struct udev_list_entry *udev_add_property(struct udev *udev, const char *key, const char *value)
+{
+        if (value == NULL) {
+                struct udev_list_entry *list_entry;
+
+                list_entry = udev_get_properties_list_entry(udev);
+                list_entry = udev_list_entry_get_by_name(list_entry, key);
+                if (list_entry != NULL)
+                        udev_list_entry_delete(list_entry);
+                return NULL;
+        }
+        return udev_list_entry_add(&udev->properties_list, key, value);
+}
+
+struct udev_list_entry *udev_get_properties_list_entry(struct udev *udev)
+{
+        return udev_list_get_entry(&udev->properties_list);
+}
diff --git a/src/libudev/libudev.h b/src/libudev/libudev.h
new file mode 100644
index 0000000000..bb41532a21
--- /dev/null
+++ b/src/libudev/libudev.h
@@ -0,0 +1,204 @@
+/***
+  This file is part of systemd.
+
+  Copyright 2008-2012 Kay Sievers <kay@vrfy.org>
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifndef _LIBUDEV_H_
+#define _LIBUDEV_H_
+
+#include <stdarg.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * udev - library context
+ *
+ * reads the udev config and system environment
+ * allows custom logging
+ */
+struct udev;
+struct udev *udev_ref(struct udev *udev);
+struct udev *udev_unref(struct udev *udev);
+struct udev *udev_new(void);
+void udev_set_log_fn(struct udev *udev,
+                            void (*log_fn)(struct udev *udev,
+                                           int priority, const char *file, int line, const char *fn,
+                                           const char *format, va_list args));
+int udev_get_log_priority(struct udev *udev);
+void udev_set_log_priority(struct udev *udev, int priority);
+void *udev_get_userdata(struct udev *udev);
+void udev_set_userdata(struct udev *udev, void *userdata);
+
+/*
+ * udev_list
+ *
+ * access to libudev generated lists
+ */
+struct udev_list_entry;
+struct udev_list_entry *udev_list_entry_get_next(struct udev_list_entry *list_entry);
+struct udev_list_entry *udev_list_entry_get_by_name(struct udev_list_entry *list_entry, const char *name);
+const char *udev_list_entry_get_name(struct udev_list_entry *list_entry);
+const char *udev_list_entry_get_value(struct udev_list_entry *list_entry);
+/**
+ * udev_list_entry_foreach:
+ * @list_entry: entry to store the current position
+ * @first_entry: first entry to start with
+ *
+ * Helper to iterate over all entries of a list.
+ */
+#define udev_list_entry_foreach(list_entry, first_entry) \
+        for (list_entry = first_entry; \
+             list_entry != NULL; \
+             list_entry = udev_list_entry_get_next(list_entry))
+
+/*
+ * udev_device
+ *
+ * access to sysfs/kernel devices
+ */
+struct udev_device;
+struct udev_device *udev_device_ref(struct udev_device *udev_device);
+struct udev_device *udev_device_unref(struct udev_device *udev_device);
+struct udev *udev_device_get_udev(struct udev_device *udev_device);
+struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath);
+struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum);
+struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname);
+struct udev_device *udev_device_new_from_device_id(struct udev *udev, char *id);
+struct udev_device *udev_device_new_from_environment(struct udev *udev);
+/* udev_device_get_parent_*() does not take a reference on the returned device, it is automatically unref'd with the parent */
+struct udev_device *udev_device_get_parent(struct udev_device *udev_device);
+struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device,
+                                                                  const char *subsystem, const char *devtype);
+/* retrieve device properties */
+const char *udev_device_get_devpath(struct udev_device *udev_device);
+const char *udev_device_get_subsystem(struct udev_device *udev_device);
+const char *udev_device_get_devtype(struct udev_device *udev_device);
+const char *udev_device_get_syspath(struct udev_device *udev_device);
+const char *udev_device_get_sysname(struct udev_device *udev_device);
+const char *udev_device_get_sysnum(struct udev_device *udev_device);
+const char *udev_device_get_devnode(struct udev_device *udev_device);
+int udev_device_get_is_initialized(struct udev_device *udev_device);
+struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device);
+struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device);
+struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device);
+struct udev_list_entry *udev_device_get_sysattr_list_entry(struct udev_device *udev_device);
+const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key);
+const char *udev_device_get_driver(struct udev_device *udev_device);
+dev_t udev_device_get_devnum(struct udev_device *udev_device);
+const char *udev_device_get_action(struct udev_device *udev_device);
+unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device);
+unsigned long long int udev_device_get_usec_since_initialized(struct udev_device *udev_device);
+const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr);
+int udev_device_has_tag(struct udev_device *udev_device, const char *tag);
+
+/*
+ * udev_monitor
+ *
+ * access to kernel uevents and udev events
+ */
+struct udev_monitor;
+struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_monitor);
+struct udev_monitor *udev_monitor_unref(struct udev_monitor *udev_monitor);
+struct udev *udev_monitor_get_udev(struct udev_monitor *udev_monitor);
+/* kernel and udev generated events over netlink */
+struct udev_monitor *udev_monitor_new_from_netlink(struct udev *udev, const char *name);
+/* bind socket */
+int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor);
+int udev_monitor_set_receive_buffer_size(struct udev_monitor *udev_monitor, int size);
+int udev_monitor_get_fd(struct udev_monitor *udev_monitor);
+struct udev_device *udev_monitor_receive_device(struct udev_monitor *udev_monitor);
+/* in-kernel socket filters to select messages that get delivered to a listener */
+int udev_monitor_filter_add_match_subsystem_devtype(struct udev_monitor *udev_monitor,
+                                                    const char *subsystem, const char *devtype);
+int udev_monitor_filter_add_match_tag(struct udev_monitor *udev_monitor, const char *tag);
+int udev_monitor_filter_update(struct udev_monitor *udev_monitor);
+int udev_monitor_filter_remove(struct udev_monitor *udev_monitor);
+
+/*
+ * udev_enumerate
+ *
+ * search sysfs for specific devices and provide a sorted list
+ */
+struct udev_enumerate;
+struct udev_enumerate *udev_enumerate_ref(struct udev_enumerate *udev_enumerate);
+struct udev_enumerate *udev_enumerate_unref(struct udev_enumerate *udev_enumerate);
+struct udev *udev_enumerate_get_udev(struct udev_enumerate *udev_enumerate);
+struct udev_enumerate *udev_enumerate_new(struct udev *udev);
+/* device properties filter */
+int udev_enumerate_add_match_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem);
+int udev_enumerate_add_nomatch_subsystem(struct udev_enumerate *udev_enumerate, const char *subsystem);
+int udev_enumerate_add_match_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value);
+int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, const char *sysattr, const char *value);
+int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value);
+int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname);
+int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag);
+int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent);
+int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev_enumerate);
+int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath);
+/* run enumeration with active filters */
+int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate);
+int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate);
+/* return device list */
+struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enumerate *udev_enumerate);
+
+/*
+ * udev_queue
+ *
+ * access to the currently running udev events
+ */
+struct udev_queue;
+struct udev_queue *udev_queue_ref(struct udev_queue *udev_queue);
+struct udev_queue *udev_queue_unref(struct udev_queue *udev_queue);
+struct udev *udev_queue_get_udev(struct udev_queue *udev_queue);
+struct udev_queue *udev_queue_new(struct udev *udev);
+unsigned long long int udev_queue_get_kernel_seqnum(struct udev_queue *udev_queue);
+unsigned long long int udev_queue_get_udev_seqnum(struct udev_queue *udev_queue);
+int udev_queue_get_udev_is_active(struct udev_queue *udev_queue);
+int udev_queue_get_queue_is_empty(struct udev_queue *udev_queue);
+int udev_queue_get_seqnum_is_finished(struct udev_queue *udev_queue, unsigned long long int seqnum);
+int udev_queue_get_seqnum_sequence_is_finished(struct udev_queue *udev_queue,
+                                               unsigned long long int start, unsigned long long int end);
+struct udev_list_entry *udev_queue_get_queued_list_entry(struct udev_queue *udev_queue);
+
+/*
+ *  udev_hwdb
+ *
+ *  access to the static hardware properties database
+ */
+struct udev_hwdb;
+struct udev_hwdb *udev_hwdb_new(struct udev *udev);
+struct udev_hwdb *udev_hwdb_ref(struct udev_hwdb *hwdb);
+struct udev_hwdb *udev_hwdb_unref(struct udev_hwdb *hwdb);
+struct udev_list_entry *udev_hwdb_get_properties_list_entry(struct udev_hwdb *hwdb, const char *modalias, unsigned int flags);
+
+/*
+ * udev_util
+ *
+ * udev specific utilities
+ */
+int udev_util_encode_string(const char *str, char *str_enc, size_t len);
+
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif
diff --git a/src/libudev/libudev.pc.in b/src/libudev/libudev.pc.in
new file mode 100644
index 0000000000..dad7139c85
--- /dev/null
+++ b/src/libudev/libudev.pc.in
@@ -0,0 +1,18 @@
+#  This file is part of systemd.
+#
+#  systemd is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU Lesser General Public License as published by
+#  the Free Software Foundation; either version 2.1 of the License, or
+#  (at your option) any later version.
+
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@includedir@
+
+Name: libudev
+Description: Library to access udev device information
+Version: @VERSION@
+Libs: -L${libdir} -ludev -lrt
+Libs.private:
+Cflags: -I${includedir}
diff --git a/src/libudev/libudev.sym b/src/libudev/libudev.sym
new file mode 100644
index 0000000000..df6a1aeddf
--- /dev/null
+++ b/src/libudev/libudev.sym
@@ -0,0 +1,110 @@
+/***
+  This file is part of systemd.
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+***/
+
+LIBUDEV_183 {
+global:
+        udev_device_get_action;
+        udev_device_get_devlinks_list_entry;
+        udev_device_get_devnode;
+        udev_device_get_devnum;
+        udev_device_get_devpath;
+        udev_device_get_devtype;
+        udev_device_get_driver;
+        udev_device_get_is_initialized;
+        udev_device_get_parent;
+        udev_device_get_parent_with_subsystem_devtype;
+        udev_device_get_properties_list_entry;
+        udev_device_get_property_value;
+        udev_device_get_seqnum;
+        udev_device_get_subsystem;
+        udev_device_get_sysattr_list_entry;
+        udev_device_get_sysattr_value;
+        udev_device_get_sysname;
+        udev_device_get_sysnum;
+        udev_device_get_syspath;
+        udev_device_get_tags_list_entry;
+        udev_device_get_udev;
+        udev_device_get_usec_since_initialized;
+        udev_device_has_tag;
+        udev_device_new_from_devnum;
+        udev_device_new_from_environment;
+        udev_device_new_from_subsystem_sysname;
+        udev_device_new_from_syspath;
+        udev_device_ref;
+        udev_device_unref;
+        udev_enumerate_add_match_is_initialized;
+        udev_enumerate_add_match_parent;
+        udev_enumerate_add_match_property;
+        udev_enumerate_add_match_subsystem;
+        udev_enumerate_add_match_sysattr;
+        udev_enumerate_add_match_sysname;
+        udev_enumerate_add_match_tag;
+        udev_enumerate_add_nomatch_subsystem;
+        udev_enumerate_add_nomatch_sysattr;
+        udev_enumerate_add_syspath;
+        udev_enumerate_get_list_entry;
+        udev_enumerate_get_udev;
+        udev_enumerate_new;
+        udev_enumerate_ref;
+        udev_enumerate_scan_devices;
+        udev_enumerate_scan_subsystems;
+        udev_enumerate_unref;
+        udev_get_log_priority;
+        udev_get_userdata;
+        udev_list_entry_get_by_name;
+        udev_list_entry_get_name;
+        udev_list_entry_get_next;
+        udev_list_entry_get_value;
+        udev_monitor_enable_receiving;
+        udev_monitor_filter_add_match_subsystem_devtype;
+        udev_monitor_filter_add_match_tag;
+        udev_monitor_filter_remove;
+        udev_monitor_filter_update;
+        udev_monitor_get_fd;
+        udev_monitor_get_udev;
+        udev_monitor_new_from_netlink;
+        udev_monitor_new_from_socket;
+        udev_monitor_receive_device;
+        udev_monitor_ref;
+        udev_monitor_set_receive_buffer_size;
+        udev_monitor_unref;
+        udev_new;
+        udev_queue_get_kernel_seqnum;
+        udev_queue_get_queue_is_empty;
+        udev_queue_get_queued_list_entry;
+        udev_queue_get_seqnum_is_finished;
+        udev_queue_get_seqnum_sequence_is_finished;
+        udev_queue_get_udev;
+        udev_queue_get_udev_is_active;
+        udev_queue_get_udev_seqnum;
+        udev_queue_new;
+        udev_queue_ref;
+        udev_queue_unref;
+        udev_ref;
+        udev_set_log_fn;
+        udev_set_log_priority;
+        udev_set_userdata;
+        udev_unref;
+        udev_util_encode_string;
+local:
+        *;
+};
+
+LIBUDEV_189 {
+global:
+        udev_device_new_from_device_id;
+} LIBUDEV_183;
+
+LIBUDEV_196 {
+global:
+        udev_hwdb_new;
+        udev_hwdb_ref;
+        udev_hwdb_unref;
+        udev_hwdb_get_properties_list_entry;
+} LIBUDEV_189;