Forward-port of libudev.so.0 code from libudev-171

Add --enable-legacylib option to configure, allowing for build and
installation of libudev.so.0 shared library for supporting pre-udev-183
software.  Library is installed to rootlibdir.

Note that this legacy library will not be maintained, and should not be used
for anything other than supporting a working system until all software
on the system is migrated to use libudev.so.1

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>

11 files changed, 6287 insertions, 0 deletions

diff --git a/src/libudev-legacy/COPYING b/src/libudev-legacy/COPYING
new file mode 100644
index 0000000000..8add30ad59
--- /dev/null
+++ b/src/libudev-legacy/COPYING
@@ -0,0 +1,504 @@
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diff --git a/src/libudev-legacy/Makefile.am b/src/libudev-legacy/Makefile.am
new file mode 100644
index 0000000000..507282b38b
--- /dev/null
+++ b/src/libudev-legacy/Makefile.am
@@ -0,0 +1,40 @@
+ACLOCAL_AMFLAGS = -I m4 ${ACLOCAL_FLAGS}
+
+define move-legacylib
+	$(MKDIR_P) $(DESTDIR)$(rootlibdir) && \
+	mv $(DESTDIR)$(libdir)/$$libname $(DESTDIR)$(rootlibdir)/libudev.so.0
+endef
+
+AM_CPPFLAGS = \
+	-include $(top_builddir)/config.h \
+	-DUDEV_CONF_FILE=\"$(udevconffile)\"
+
+lib_LTLIBRARIES = \
+	libudev-legacy.la
+
+libudev_legacy_la_SOURCES =\
+	libudev.c \
+	libudev-list.c \
+	libudev-util.c \
+	libudev-device.c \
+	libudev-enumerate.c \
+	libudev-monitor.c \
+	libudev-queue.c
+
+libudev_legacy_la_CFLAGS =\
+	$(AM_CFLAGS) \
+	-shared
+
+noinst_HEADERS = \
+	libudev.h \
+	libudev-private.h
+
+libudev_legacy_la_LDFLAGS = \
+	$(AM_LDFLAGS) \
+	-avoid-version
+
+install-exec-hook:
+	libname=libudev-legacy.so && $(move-legacylib)
+
+EXTRA_DIST = \
+	COPYING
diff --git a/src/libudev-legacy/libudev-device.c b/src/libudev-legacy/libudev-device.c
new file mode 100644
index 0000000000..8289acf3a9
--- /dev/null
+++ b/src/libudev-legacy/libudev-device.c
@@ -0,0 +1,1775 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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 *knodename;
+	char *id_filename;
+	char **envp;
+	char *monitor_buf;
+	size_t monitor_buf_len;
+	struct udev_list_node devlinks_list;
+	struct udev_list_node properties_list;
+	struct udev_list_node sysattr_value_list;
+	struct udev_list_node sysattr_list;
+	struct udev_list_node tags_list;
+	unsigned long long int seqnum;
+	unsigned long long int usec_initialized;
+	int timeout;
+	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_devnum:
+ * @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.
+ **/
+UDEV_EXPORT 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
+ *
+ * Returns: the device major/minor number.
+ **/
+UDEV_EXPORT 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;
+}
+
+int udev_device_get_timeout(struct udev_device *udev_device)
+{
+	return udev_device->timeout;
+}
+
+static int udev_device_set_timeout(struct udev_device *udev_device, int timeout)
+{
+	char num[32];
+
+	udev_device->timeout = timeout;
+	snprintf(num, sizeof(num), "%u", timeout);
+	udev_device_add_property(udev_device, "TIMEOUT", num);
+	return 0;
+}
+
+const char *udev_device_get_knodename(struct udev_device *udev_device)
+{
+	return udev_device->knodename;
+}
+
+static int udev_device_set_knodename(struct udev_device *udev_device, const char *knodename)
+{
+	free(udev_device->knodename);
+	udev_device->knodename = strdup(knodename);
+	if (udev_device->knodename == NULL)
+		return -ENOMEM;
+	/* do not overwrite the udev property with the kernel property */
+	if (udev_device->devnode == NULL)
+		udev_device_add_property(udev_device, "DEVNAME", udev_device->knodename);
+	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
+ *
+ * Returns: the driver string, or #NULL if there is no driver attached.
+ **/
+UDEV_EXPORT 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_driver(udev_device->udev, 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
+ **/
+UDEV_EXPORT 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;
+}
+
+static 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
+ **/
+UDEV_EXPORT 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_subsystem(udev_device->udev, udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
+			udev_device_set_subsystem(udev_device, subsystem);
+			return udev_device->subsystem;
+		}
+		/* implicit names */
+		if (strncmp(udev_device->devpath, "/module/", 8) == 0) {
+			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 (strncmp(udev_device->devpath, "/subsystem/", 11) == 0 ||
+		    strncmp(udev_device->devpath, "/class/", 7) == 0 ||
+		    strncmp(udev_device->devpath, "/bus/", 5) == 0) {
+			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->udev, &udev_device->properties_list, key, value, UDEV_LIST_UNIQUE);
+}
+
+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 (strncmp(property, "DEVPATH=", 8) == 0) {
+		char path[UTIL_PATH_SIZE];
+
+		util_strscpyl(path, sizeof(path), udev_get_sys_path(udev_device->udev), &property[8], NULL);
+		udev_device_set_syspath(udev_device, path);
+	} else if (strncmp(property, "SUBSYSTEM=", 10) == 0) {
+		udev_device_set_subsystem(udev_device, &property[10]);
+	} else if (strncmp(property, "DEVTYPE=", 8) == 0) {
+		udev_device_set_devtype(udev_device, &property[8]);
+	} else if (strncmp(property, "DEVNAME=", 8) == 0) {
+		if (property[8] == '/')
+			udev_device_set_devnode(udev_device, &property[8]);
+		else
+			udev_device_set_knodename(udev_device, &property[8]);
+	} else if (strncmp(property, "DEVLINKS=", 9) == 0) {
+		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, 0);
+			slink = &next[1];
+			next = strchr(slink, ' ');
+		}
+		if (slink[0] != '\0')
+			udev_device_add_devlink(udev_device, slink, 0);
+	} else if (strncmp(property, "TAGS=", 5) == 0) {
+		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 (strncmp(property, "DRIVER=", 7) == 0) {
+		udev_device_set_driver(udev_device, &property[7]);
+	} else if (strncmp(property, "ACTION=", 7) == 0) {
+		udev_device_set_action(udev_device, &property[7]);
+	} else if (strncmp(property, "MAJOR=", 6) == 0) {
+		udev_device->maj = strtoull(&property[6], NULL, 10);
+	} else if (strncmp(property, "MINOR=", 6) == 0) {
+		udev_device->min = strtoull(&property[6], NULL, 10);
+	} else if (strncmp(property, "DEVPATH_OLD=", 12) == 0) {
+		udev_device_set_devpath_old(udev_device, &property[12]);
+	} else if (strncmp(property, "SEQNUM=", 7) == 0) {
+		udev_device_set_seqnum(udev_device, strtoull(&property[7], NULL, 10));
+	} else if (strncmp(property, "TIMEOUT=", 8) == 0) {
+		udev_device_set_timeout(udev_device, strtoull(&property[8], NULL, 10));
+	} else if (strncmp(property, "IFINDEX=", 8) == 0) {
+		udev_device_set_ifindex(udev_device, strtoull(&property[8], NULL, 10));
+	} else if (strncmp(property, "DEVMODE=", 8) == 0) {
+		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
+ *
+ * Returns: the value of a device property, or #NULL if there is no such property.
+ **/
+UDEV_EXPORT 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), udev_get_run_path(udev_device->udev), "/data/", id, NULL);
+		dbfile = filename;
+	}
+
+	f = fopen(dbfile, "re");
+	if (f == NULL) {
+		info(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 'N':
+			util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/", val, NULL);
+			udev_device_set_devnode(udev_device, filename);
+			break;
+		case 'S':
+			util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/", val, NULL);
+			udev_device_add_devlink(udev_device, filename, 0);
+			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);
+
+	info(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 (strncmp(line, "DEVTYPE=", 8) == 0)
+			udev_device_set_devtype(udev_device, &line[8]);
+		else if (strncmp(line, "MAJOR=", 6) == 0)
+			maj = strtoull(&line[6], NULL, 10);
+		else if (strncmp(line, "MINOR=", 6) == 0)
+			min = strtoull(&line[6], NULL, 10);
+		else if (strncmp(line, "IFINDEX=", 8) == 0)
+			udev_device_set_ifindex(udev_device, strtoull(&line[8], NULL, 10));
+		else if (strncmp(line, "DEVNAME=", 8) == 0)
+			udev_device_set_knodename(udev_device, &line[8]);
+		else if (strncmp(line, "DEVMODE=", 8) == 0)
+			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_device->devlinks_list);
+	udev_list_init(&udev_device->properties_list);
+	udev_list_init(&udev_device->sysattr_value_list);
+	udev_list_init(&udev_device->sysattr_list);
+	udev_list_init(&udev_device->tags_list);
+	udev_device->timeout = -1;
+	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));
+	dbg(udev_device->udev, "udev_device: %p created\n", udev_device);
+	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
+ **/
+UDEV_EXPORT struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
+{
+	size_t len;
+	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 */
+	len = strlen(udev_get_sys_path(udev));
+	if (strncmp(syspath, udev_get_sys_path(udev), len) != 0) {
+		info(udev, "not in sys :%s\n", syspath);
+		return NULL;
+	}
+
+	/* path is not a root directory */
+	subdir = &syspath[len+1];
+	pos = strrchr(subdir, '/');
+	if (pos == NULL || pos[1] == '\0' || pos < &subdir[2]) {
+		dbg(udev, "not a subdir :%s\n", syspath);
+		return NULL;
+	}
+
+	/* resolve possible symlink to real path */
+	util_strscpy(path, sizeof(path), syspath);
+	util_resolve_sys_link(udev, path, sizeof(path));
+
+	if (strncmp(&path[len], "/devices/", 9) == 0) {
+		char file[UTIL_PATH_SIZE];
+
+		/* all "devices" require a "uevent" file */
+		util_strscpyl(file, sizeof(file), path, "/uevent", NULL);
+		if (stat(file, &statbuf) != 0) {
+			dbg(udev, "not a device: %s\n", syspath);
+			return NULL;
+		}
+	} else {
+		/* everything else just needs to be a directory */
+		if (stat(path, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) {
+			dbg(udev, "directory not found: %s\n", syspath);
+			return NULL;
+		}
+	}
+
+	udev_device = udev_device_new(udev);
+	if (udev_device == NULL)
+		return NULL;
+
+	udev_device_set_syspath(udev_device, path);
+	info(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
+ **/
+UDEV_EXPORT 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), "%s/dev/%s/%u:%u",
+		 udev_get_sys_path(udev), type_str, major(devnum), minor(devnum));
+	return udev_device_new_from_syspath(udev, path);
+}
+
+struct udev_device *udev_device_new_from_id_filename(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
+ **/
+UDEV_EXPORT struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
+{
+	char path_full[UTIL_PATH_SIZE];
+	char *path;
+	size_t l;
+	struct stat statbuf;
+
+	path = path_full;
+	l = util_strpcpyl(&path, sizeof(path_full), udev_get_sys_path(udev), NULL);
+
+	if (strcmp(subsystem, "subsystem") == 0) {
+		util_strscpyl(path, l, "/subsystem/", sysname, NULL);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+
+		util_strscpyl(path, l, "/bus/", sysname, NULL);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+
+		util_strscpyl(path, l, "/class/", sysname, NULL);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+		goto out;
+	}
+
+	if (strcmp(subsystem, "module") == 0) {
+		util_strscpyl(path, l, "/module/", sysname, NULL);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+		goto out;
+	}
+
+	if (strcmp(subsystem, "drivers") == 0) {
+		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, l, "/subsystem/", subsys, "/drivers/", driver, NULL);
+			if (stat(path_full, &statbuf) == 0)
+				goto found;
+
+			util_strscpyl(path, l, "/bus/", subsys, "/drivers/", driver, NULL);
+			if (stat(path_full, &statbuf) == 0)
+				goto found;
+		}
+		goto out;
+	}
+
+	util_strscpyl(path, l, "/subsystem/", subsystem, "/devices/", sysname, NULL);
+	if (stat(path_full, &statbuf) == 0)
+		goto found;
+
+	util_strscpyl(path, l, "/bus/", subsystem, "/devices/", sysname, NULL);
+	if (stat(path_full, &statbuf) == 0)
+		goto found;
+
+	util_strscpyl(path, l, "/class/", subsystem, "/", sysname, NULL);
+	if (stat(path_full, &statbuf) == 0)
+		goto found;
+out:
+	return NULL;
+found:
+	return udev_device_new_from_syspath(udev, path_full);
+}
+
+/**
+ * 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
+ **/
+UDEV_EXPORT 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) {
+		info(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(udev_get_sys_path(udev_device->udev))+1];
+	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.
+ **/
+UDEV_EXPORT 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);
+	}
+	if (udev_device->parent_device != NULL)
+		dbg(udev_device->udev, "returning existing parent %p\n", udev_device->parent_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.
+ **/
+UDEV_EXPORT 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 && strcmp(parent_subsystem, subsystem) == 0) {
+			if (devtype == NULL)
+				break;
+			parent_devtype = udev_device_get_devtype(parent);
+			if (parent_devtype != NULL && strcmp(parent_devtype, devtype) == 0)
+				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
+ **/
+UDEV_EXPORT 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
+ **/
+UDEV_EXPORT 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.
+ *
+ **/
+UDEV_EXPORT void udev_device_unref(struct udev_device *udev_device)
+{
+	if (udev_device == NULL)
+		return;
+	udev_device->refcount--;
+	if (udev_device->refcount > 0)
+		return;
+	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_entries(udev_device->udev, &udev_device->devlinks_list);
+	udev_list_cleanup_entries(udev_device->udev, &udev_device->properties_list);
+	udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_value_list);
+	udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
+	udev_list_cleanup_entries(udev_device->udev, &udev_device->tags_list);
+	free(udev_device->action);
+	free(udev_device->driver);
+	free(udev_device->devpath_old);
+	free(udev_device->knodename);
+	free(udev_device->id_filename);
+	free(udev_device->envp);
+	free(udev_device->monitor_buf);
+	dbg(udev_device->udev, "udev_device: %p released\n", udev_device);
+	free(udev_device);
+}
+
+/**
+ * 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
+ **/
+UDEV_EXPORT 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
+ **/
+UDEV_EXPORT 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
+ *
+ * Returns: the sys name of the device device
+ **/
+UDEV_EXPORT 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
+ *
+ * Returns: the trailing number of of the device name
+ **/
+UDEV_EXPORT 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
+ **/
+UDEV_EXPORT const char *udev_device_get_devnode(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);
+	}
+
+	/* we might get called before we handled an event and have a db, use the kernel-provided name */
+	if (udev_device->devnode == NULL && udev_device_get_knodename(udev_device) != NULL) {
+		char filename[UTIL_NAME_SIZE];
+
+		util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/",
+			      udev_device_get_knodename(udev_device), NULL);
+		udev_device_set_devnode(udev_device, filename);
+		return udev_device->devnode;
+	}
+
+	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_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
+ **/
+UDEV_EXPORT 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_entries(udev_device->udev, &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_next(),
+ * which returns #NULL if no more entries exist. The property name
+ * can be retrieved from the list entry by udev_list_get_name(),
+ * the property value by udev_list_get_value().
+ *
+ * Returns: the first entry of the property list
+ **/
+UDEV_EXPORT 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.
+ **/
+UDEV_EXPORT 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.
+ **/
+UDEV_EXPORT unsigned long long int udev_device_get_usec_since_initialized(struct udev_device *udev_device)
+{
+	unsigned long long now;
+
+	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 = now_usec();
+	if (now == 0)
+		return 0;
+	return now - udev_device->usec_initialized;
+}
+
+unsigned long long 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, unsigned long long usec_initialized)
+{
+	udev_device->usec_initialized = usec_initialized;
+}
+
+/**
+ * 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.
+ **/
+UDEV_EXPORT 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 */
+	udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_device->sysattr_value_list)) {
+		if (strcmp(udev_list_entry_get_name(list_entry), sysattr) == 0) {
+			dbg(udev_device->udev, "got '%s' (%s) from cache\n",
+			    sysattr, udev_list_entry_get_value(list_entry));
+			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) {
+		dbg(udev_device->udev, "no attribute '%s', keep negative entry\n", path);
+		udev_list_entry_add(udev_device->udev, &udev_device->sysattr_value_list, sysattr, NULL, 0);
+		goto out;
+	}
+
+	if (S_ISLNK(statbuf.st_mode)) {
+		char target[UTIL_NAME_SIZE];
+		int len;
+		char *pos;
+
+		/* some core links return the last element of the target path */
+		if (strcmp(sysattr, "driver") != 0 &&
+		    strcmp(sysattr, "subsystem") != 0 &&
+		    strcmp(sysattr, "module") != 0)
+			goto out;
+
+		len = readlink(path, target, sizeof(target));
+		if (len <= 0 || len == sizeof(target))
+			goto out;
+		target[len] = '\0';
+
+		pos = strrchr(target, '/');
+		if (pos != NULL) {
+			pos = &pos[1];
+			dbg(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, pos);
+			list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_value_list, sysattr, pos, 0);
+			val = udev_list_entry_get_value(list_entry);
+		}
+
+		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) {
+		dbg(udev_device->udev, "attribute '%s' can not be opened\n", path);
+		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');
+	dbg(udev_device->udev, "'%s' has attribute value '%s'\n", path, value);
+	list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_value_list, sysattr, value, 0);
+	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) {
+		dbg(udev_device->udev, "sysfs dir '%s' can not be opened\n",
+				udev_device_get_syspath(udev_device));
+		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->udev, &udev_device->sysattr_list,
+				    dent->d_name, NULL, 0);
+		num++;
+	}
+
+	closedir(dir);
+	dbg(udev_device->udev, "found %d sysattrs for '%s'\n", num, udev_device_get_syspath(udev_device));
+	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
+ **/
+UDEV_EXPORT 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(udev_get_sys_path(udev_device->udev))];
+	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);
+	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, int unique)
+{
+	struct udev_list_entry *list_entry;
+
+	udev_device->devlinks_uptodate = false;
+	list_entry = udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, UDEV_LIST_UNIQUE);
+	if (list_entry == NULL)
+		return -ENOMEM;
+	if (unique)
+		udev_list_entry_set_num(list_entry, true);
+	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",
+				     strcmp(udev_device_get_subsystem(udev_device), "block") == 0 ? '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.
+ **/
+UDEV_EXPORT 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->udev, &udev_device->tags_list, tag, NULL, UDEV_LIST_UNIQUE) != NULL)
+		return 0;
+	return -ENOMEM;
+}
+
+void udev_device_cleanup_tags_list(struct udev_device *udev_device)
+{
+	udev_device->tags_uptodate = false;
+	udev_list_cleanup_entries(udev_device->udev, &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_next(),
+ * which returns #NULL if no more entries exist. The tag string
+ * can be retrieved from the list entry by udev_list_get_name().
+ *
+ * Returns: the first entry of the tag list
+ **/
+UDEV_EXPORT struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device)
+{
+	if (udev_device == NULL)
+		return NULL;
+	return udev_list_get_entry(&udev_device->tags_list);
+}
+
+int udev_device_has_tag(struct udev_device *udev_device, const char *tag)
+{
+	struct udev_list_entry *list_entry;
+
+	if (!udev_device->info_loaded)
+		udev_device_read_db(udev_device, NULL);
+	list_entry = udev_device_get_tags_list_entry(udev_device);
+	list_entry =  udev_list_entry_get_by_name(list_entry, tag);
+	if (list_entry != NULL)
+		return 1;
+	return 0;
+}
+
+#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;
+	dbg(udev_device->udev, "filled envp/monitor buffer, %u properties, %zu bytes\n",
+	    i, udev_device->monitor_buf_len);
+	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-legacy/libudev-enumerate.c b/src/libudev-legacy/libudev-enumerate.c
new file mode 100644
index 0000000000..6e51726f08
--- /dev/null
+++ b/src/libudev-legacy/libudev-enumerate.c
@@ -0,0 +1,831 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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_node sysattr_match_list;
+	struct udev_list_node sysattr_nomatch_list;
+	struct udev_list_node subsystem_match_list;
+	struct udev_list_node subsystem_nomatch_list;
+	struct udev_list_node sysname_match_list;
+	struct udev_list_node properties_match_list;
+	struct udev_list_node tags_match_list;
+	struct udev_list_node 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
+ *
+ * Returns: an enumeration context
+ **/
+UDEV_EXPORT 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_enumerate->sysattr_match_list);
+	udev_list_init(&udev_enumerate->sysattr_nomatch_list);
+	udev_list_init(&udev_enumerate->subsystem_match_list);
+	udev_list_init(&udev_enumerate->subsystem_nomatch_list);
+	udev_list_init(&udev_enumerate->sysname_match_list);
+	udev_list_init(&udev_enumerate->properties_match_list);
+	udev_list_init(&udev_enumerate->tags_match_list);
+	udev_list_init(&udev_enumerate->devices_list);
+	return udev_enumerate;
+}
+
+/**
+ * udev_enumerate_ref:
+ * @udev_enumerate: context
+ *
+ * Take a reference of a enumeration context.
+ *
+ * Returns: the passed enumeration context
+ **/
+UDEV_EXPORT 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.
+ **/
+UDEV_EXPORT void udev_enumerate_unref(struct udev_enumerate *udev_enumerate)
+{
+	unsigned int i;
+
+	if (udev_enumerate == NULL)
+		return;
+	udev_enumerate->refcount--;
+	if (udev_enumerate->refcount > 0)
+		return;
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysattr_match_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysattr_nomatch_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->subsystem_match_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->subsystem_nomatch_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysname_match_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->properties_match_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->tags_match_list);
+	udev_list_cleanup_entries(udev_enumerate->udev, &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);
+}
+
+/**
+ * udev_enumerate_get_udev:
+ * @udev_enumerate: context
+ *
+ * Returns: the udev library context.
+ */
+UDEV_EXPORT 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
+	};
+	size_t len;
+	int i;
+
+	len = strlen(udev_get_sys_path(udev));
+	for (i = 0; delay_device_list[i] != NULL; i++) {
+		if (strstr(&syspath[len], delay_device_list[i]) != NULL) {
+			dbg(udev, "delaying: %s\n", syspath);
+			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 (strncmp(c, "/controlC", 9) == 0)
+			return c - syspath + 1;
+	}
+
+	return 0;
+}
+
+/**
+ * udev_enumerate_get_list_entry:
+ * @udev_enumerate: context
+ *
+ * Returns: the first entry of the sorted list of device paths.
+ */
+UDEV_EXPORT 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_entries(udev_enumerate->udev, &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->udev, &udev_enumerate->devices_list,
+					    move_later->syspath, NULL, 0);
+				move_later = NULL;
+			}
+
+			udev_list_entry_add(udev_enumerate->udev, &udev_enumerate->devices_list,
+					    entry->syspath, NULL, 0);
+		}
+
+		if (move_later)
+			udev_list_entry_add(udev_enumerate->udev, &udev_enumerate->devices_list,
+					    move_later->syspath, NULL, 0);
+
+		/* 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->udev, &udev_enumerate->devices_list,
+					    entry->syspath, NULL, 0);
+			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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+				&udev_enumerate->subsystem_match_list, subsystem, NULL, UDEV_LIST_UNIQUE) == 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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+				&udev_enumerate->subsystem_nomatch_list, subsystem, NULL, UDEV_LIST_UNIQUE) == 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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+				&udev_enumerate->sysattr_match_list, sysattr, value, 0) == 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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+			   &udev_enumerate->sysattr_nomatch_list, sysattr, value, 0) == 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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+				&udev_enumerate->properties_match_list, property, value, 0) == 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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+				&udev_enumerate->tags_match_list, tag, NULL, UDEV_LIST_UNIQUE) == NULL)
+		return -ENOMEM;
+	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.
+ */
+UDEV_EXPORT 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
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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_get_udev(udev_enumerate),
+				&udev_enumerate->sysname_match_list, sysname, NULL, UDEV_LIST_UNIQUE) == 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_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)
+{
+	struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
+	char path[UTIL_PATH_SIZE];
+	size_t l;
+	char *s;
+	DIR *dir;
+	struct dirent *dent;
+
+	s = path;
+	l = util_strpcpyl(&s, sizeof(path), udev_get_sys_path(udev), "/", 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_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)
+{
+	struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
+
+	char path[UTIL_PATH_SIZE];
+	DIR *dir;
+	struct dirent *dent;
+
+	util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/", 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.
+ */
+UDEV_EXPORT 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;
+}
+
+/**
+ * udev_enumerate_scan_devices:
+ * @udev_enumerate: udev enumeration context
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ **/
+UDEV_EXPORT int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate)
+{
+	struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
+	char base[UTIL_PATH_SIZE];
+	struct stat statbuf;
+
+	if (udev_enumerate == NULL)
+		return -EINVAL;
+
+	if (udev_list_get_entry(&udev_enumerate->tags_match_list) != NULL) {
+		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), udev_get_run_path(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_id_filename(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_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);
+		}
+	} else {
+		util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
+		if (stat(base, &statbuf) == 0) {
+			/* we have /subsystem/, forget all the old stuff */
+			dbg(udev, "searching '/subsystem/*/devices/*' dir\n");
+			scan_dir(udev_enumerate, "subsystem", "devices", NULL);
+		} else {
+		dbg(udev, "searching '/bus/*/devices/*' dir\n");
+			scan_dir(udev_enumerate, "bus", "devices", NULL);
+			dbg(udev, "searching '/class/*' dir\n");
+			scan_dir(udev_enumerate, "class", NULL, NULL);
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * udev_enumerate_scan_subsystems:
+ * @udev_enumerate: udev enumeration context
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ **/
+UDEV_EXPORT int udev_enumerate_scan_subsystems(struct udev_enumerate *udev_enumerate)
+{
+	struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
+	char base[UTIL_PATH_SIZE];
+	struct stat statbuf;
+	const char *subsysdir;
+
+	if (udev_enumerate == NULL)
+		return -EINVAL;
+
+	util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
+	if (stat(base, &statbuf) == 0)
+		subsysdir = "subsystem";
+	else
+		subsysdir = "bus";
+	if (match_subsystem(udev_enumerate, "subsystem")) {
+		dbg(udev, "searching '%s/*' dir\n", subsysdir);
+		scan_dir_and_add_devices(udev_enumerate, subsysdir, NULL, NULL);
+	}
+	if (match_subsystem(udev_enumerate, "drivers")) {
+		dbg(udev, "searching '%s/*/drivers/*' dir\n", subsysdir);
+		scan_dir(udev_enumerate, subsysdir, "drivers", "drivers");
+	}
+	return 0;
+}
diff --git a/src/libudev-legacy/libudev-list.c b/src/libudev-legacy/libudev-list.c
new file mode 100644
index 0000000000..e828a4e4c6
--- /dev/null
+++ b/src/libudev-legacy/libudev-list.c
@@ -0,0 +1,278 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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 *udev;
+	struct udev_list_node *list;
+	char *name;
+	char *value;
+	int num;
+};
+
+/* the list's head points to itself if empty */
+void udev_list_init(struct udev_list_node *list)
+{
+	list->next = list;
+	list->prev = list;
+}
+
+int udev_list_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 struct udev_list_entry *list_node_to_entry(struct udev_list_node *node)
+{
+	char *list;
+
+	list = (char *)node;
+	list -= offsetof(struct udev_list_entry, node);
+	return (struct udev_list_entry *)list;
+}
+
+/* insert entry into a list as the last element  */
+void udev_list_entry_append(struct udev_list_entry *new, struct udev_list_node *list)
+{
+	/* inserting before the list head make the node the last node in the list */
+	udev_list_node_insert_between(&new->node, list->prev, list);
+	new->list = list;
+}
+
+/* remove entry from a list */
+void udev_list_entry_remove(struct udev_list_entry *entry)
+{
+	udev_list_node_remove(&entry->node);
+	entry->list = NULL;
+}
+
+/* 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;
+}
+
+struct udev_list_entry *udev_list_entry_add(struct udev *udev, struct udev_list_node *list,
+					    const char *name, const char *value,
+					    unsigned int flags)
+{
+	struct udev_list_entry *entry_loop = NULL;
+	struct udev_list_entry *entry_new;
+
+	if (flags & UDEV_LIST_UNIQUE) {
+		udev_list_entry_foreach(entry_loop, udev_list_get_entry(list)) {
+			if (strcmp(entry_loop->name, name) == 0) {
+				dbg(udev, "'%s' is already in the list\n", name);
+				free(entry_loop->value);
+				if (value == NULL) {
+					entry_loop->value = NULL;
+					dbg(udev, "'%s' value unset\n", name);
+					return entry_loop;
+				}
+				entry_loop->value = strdup(value);
+				if (entry_loop->value == NULL)
+					return NULL;
+				dbg(udev, "'%s' value replaced with '%s'\n", name, value);
+				return entry_loop;
+			}
+		}
+	}
+
+	if (flags & UDEV_LIST_SORT) {
+		udev_list_entry_foreach(entry_loop, udev_list_get_entry(list)) {
+			if (strcmp(entry_loop->name, name) > 0)
+				break;
+		}
+	}
+
+	entry_new = malloc(sizeof(struct udev_list_entry));
+	if (entry_new == NULL)
+		return NULL;
+	memset(entry_new, 0x00, sizeof(struct udev_list_entry));
+	entry_new->udev = udev;
+	entry_new->name = strdup(name);
+	if (entry_new->name == NULL) {
+		free(entry_new);
+		return NULL;
+	}
+
+	if (value != NULL) {
+		entry_new->value = strdup(value);
+		if (entry_new->value == NULL) {
+			free(entry_new->name);
+			free(entry_new);
+			return NULL;
+		}
+	}
+
+	if (entry_loop != NULL)
+		udev_list_entry_insert_before(entry_new, entry_loop);
+	else
+		udev_list_entry_append(entry_new, list);
+
+	dbg(udev, "'%s=%s' added\n", entry_new->name, entry_new->value);
+	return entry_new;
+}
+
+void udev_list_entry_delete(struct udev_list_entry *entry)
+{
+	udev_list_node_remove(&entry->node);
+	free(entry->name);
+	free(entry->value);
+	free(entry);
+}
+
+void udev_list_cleanup_entries(struct udev *udev, struct udev_list_node *list)
+{
+	struct udev_list_entry *entry_loop;
+	struct udev_list_entry *entry_tmp;
+
+	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_node *list)
+{
+	if (udev_list_is_empty(list))
+		return NULL;
+	return list_node_to_entry(list->next);
+}
+
+/**
+ * udev_list_entry_get_next:
+ * @list_entry: current entry
+ *
+ * Returns: the next entry from the list, #NULL is no more entries are found.
+ */
+UDEV_EXPORT 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)
+		return NULL;
+	return list_node_to_entry(next);
+}
+
+/**
+ * udev_list_entry_get_by_name:
+ * @list_entry: current entry
+ * @name: name string to match
+ *
+ * Returns: the entry where @name matched, #NULL if no matching entry is found.
+ */
+UDEV_EXPORT struct udev_list_entry *udev_list_entry_get_by_name(struct udev_list_entry *list_entry, const char *name)
+{
+	struct udev_list_entry *entry;
+
+	udev_list_entry_foreach(entry, list_entry) {
+		if (strcmp(udev_list_entry_get_name(entry), name) == 0) {
+			dbg(entry->udev, "found '%s=%s'\n", entry->name, entry->value);
+			return entry;
+		}
+	}
+	return NULL;
+}
+
+/**
+ * udev_list_entry_get_name:
+ * @list_entry: current entry
+ *
+ * Returns: the name string of this entry.
+ */
+UDEV_EXPORT 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
+ *
+ * Returns: the value string of this entry.
+ */
+UDEV_EXPORT 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-legacy/libudev-monitor.c b/src/libudev-legacy/libudev-monitor.c
new file mode 100644
index 0000000000..85ab23bdd4
--- /dev/null
+++ b/src/libudev-legacy/libudev-monitor.c
@@ -0,0 +1,876 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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"
+
+/**
+ * SECTION:libudev-monitor
+ * @short_description: device event source
+ *
+ * Connects to a device event source.
+ */
+
+/**
+ * udev_monitor:
+ *
+ * Opaque object handling one event source.
+ */
+struct udev_monitor {
+	struct udev *udev;
+	int refcount;
+	int sock;
+	struct sockaddr_nl snl;
+	struct sockaddr_nl snl_trusted_sender;
+	struct sockaddr_nl snl_destination;
+	struct sockaddr_un sun;
+	socklen_t addrlen;
+	struct udev_list_node filter_subsystem_list;
+	struct udev_list_node 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_monitor->filter_subsystem_list);
+	udev_list_init(&udev_monitor->filter_tag_list);
+	return udev_monitor;
+}
+
+/**
+ * udev_monitor_new_from_socket:
+ * @udev: udev library context
+ * @socket_path: unix socket path
+ *
+ * Create new udev monitor and connect to a specified socket. The
+ * path to a socket either points to an existing socket file, or if
+ * the socket path starts with a '@' character, an abstract namespace
+ * socket will be used.
+ *
+ * A socket file will not be created. If it does not already exist,
+ * it will fall-back and connect to an abstract namespace socket with
+ * the given path. The permissions adjustment of a socket file, as
+ * well as the later cleanup, needs to be done by the caller.
+ *
+ * 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
+ **/
+UDEV_EXPORT struct udev_monitor *udev_monitor_new_from_socket(struct udev *udev, const char *socket_path)
+{
+	struct udev_monitor *udev_monitor;
+	struct stat statbuf;
+
+	if (udev == NULL)
+		return NULL;
+	if (socket_path == NULL)
+		return NULL;
+	udev_monitor = udev_monitor_new(udev);
+	if (udev_monitor == NULL)
+		return NULL;
+
+	udev_monitor->sun.sun_family = AF_LOCAL;
+	if (socket_path[0] == '@') {
+		/* translate leading '@' to abstract namespace */
+		util_strscpy(udev_monitor->sun.sun_path, sizeof(udev_monitor->sun.sun_path), socket_path);
+		udev_monitor->sun.sun_path[0] = '\0';
+		udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path);
+	} else if (stat(socket_path, &statbuf) == 0 && S_ISSOCK(statbuf.st_mode)) {
+		/* existing socket file */
+		util_strscpy(udev_monitor->sun.sun_path, sizeof(udev_monitor->sun.sun_path), socket_path);
+		udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path);
+	} else {
+		/* no socket file, assume abstract namespace socket */
+		util_strscpy(&udev_monitor->sun.sun_path[1], sizeof(udev_monitor->sun.sun_path)-1, socket_path);
+		udev_monitor->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(socket_path)+1;
+	}
+	udev_monitor->sock = socket(AF_LOCAL, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0);
+	if (udev_monitor->sock == -1) {
+		err(udev, "error getting socket: %m\n");
+		free(udev_monitor);
+		return NULL;
+	}
+
+	dbg(udev, "monitor %p created with '%s'\n", udev_monitor, socket_path);
+	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) {
+			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_family = AF_NETLINK;
+	udev_monitor->snl.nl_groups = group;
+
+	/* default destination for sending */
+	udev_monitor->snl_destination.nl_family = AF_NETLINK;
+	udev_monitor->snl_destination.nl_groups = UDEV_MONITOR_UDEV;
+
+	dbg(udev, "monitor %p created with NETLINK_KOBJECT_UEVENT (%u)\n", udev_monitor, group);
+	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
+ **/
+UDEV_EXPORT 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 filter. This might only be needed, if the filter was removed or changed.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT 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 >= ARRAY_SIZE(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_pid = sender->snl.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.
+ */
+UDEV_EXPORT int udev_monitor_enable_receiving(struct udev_monitor *udev_monitor)
+{
+	int err = 0;
+	const int on = 1;
+
+	if (udev_monitor->sun.sun_family != 0) {
+		if (!udev_monitor->bound) {
+			err = bind(udev_monitor->sock,
+				   (struct sockaddr *)&udev_monitor->sun, udev_monitor->addrlen);
+			if (err == 0)
+				udev_monitor->bound = true;
+		}
+	} else if (udev_monitor->snl.nl_family != 0) {
+		udev_monitor_filter_update(udev_monitor);
+		if (!udev_monitor->bound) {
+			err = bind(udev_monitor->sock,
+				   (struct sockaddr *)&udev_monitor->snl, sizeof(struct sockaddr_nl));
+			if (err == 0)
+				udev_monitor->bound = true;
+		}
+		if (err == 0) {
+			struct sockaddr_nl 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, (struct sockaddr *)&snl, &addrlen);
+			if (err == 0)
+				udev_monitor->snl.nl_pid = snl.nl_pid;
+		}
+	} else {
+		return -EINVAL;
+	}
+
+	if (err < 0) {
+		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.
+ */
+UDEV_EXPORT 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
+ **/
+UDEV_EXPORT 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.
+ *
+ **/
+UDEV_EXPORT void udev_monitor_unref(struct udev_monitor *udev_monitor)
+{
+	if (udev_monitor == NULL)
+		return;
+	udev_monitor->refcount--;
+	if (udev_monitor->refcount > 0)
+		return;
+	if (udev_monitor->sock >= 0)
+		close(udev_monitor->sock);
+	udev_list_cleanup_entries(udev_monitor->udev, &udev_monitor->filter_subsystem_list);
+	udev_list_cleanup_entries(udev_monitor->udev, &udev_monitor->filter_tag_list);
+	dbg(udev_monitor->udev, "monitor %p released\n", udev_monitor);
+	free(udev_monitor);
+}
+
+/**
+ * udev_monitor_get_udev:
+ * @udev_monitor: udev monitor
+ *
+ * Retrieve the udev library context the monitor was created with.
+ *
+ * Returns: the udev library context
+ **/
+UDEV_EXPORT 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
+ **/
+UDEV_EXPORT 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 caller
+ * needs to make sure that there is data to read from the socket.
+ * The call will block until the socket becomes readable.
+ *
+ * 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
+ **/
+UDEV_EXPORT 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;
+	struct sockaddr_nl 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;
+	memset(buf, 0x00, sizeof(buf));
+	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_family != 0) {
+		smsg.msg_name = &snl;
+		smsg.msg_namelen = sizeof(snl);
+	}
+
+	buflen = recvmsg(udev_monitor->sock, &smsg, 0);
+	if (buflen < 0) {
+		if (errno != EINTR)
+			info(udev_monitor->udev, "unable to receive message\n");
+		return NULL;
+	}
+
+	if (buflen < 32 || (size_t)buflen >= sizeof(buf)) {
+		info(udev_monitor->udev, "invalid message length\n");
+		return NULL;
+	}
+
+	if (udev_monitor->snl.nl_family != 0) {
+		if (snl.nl_groups == 0) {
+			/* unicast message, check if we trust the sender */
+			if (udev_monitor->snl_trusted_sender.nl_pid == 0 ||
+			    snl.nl_pid != udev_monitor->snl_trusted_sender.nl_pid) {
+				info(udev_monitor->udev, "unicast netlink message ignored\n");
+				return NULL;
+			}
+		} else if (snl.nl_groups == UDEV_MONITOR_KERNEL) {
+			if (snl.nl_pid > 0) {
+				info(udev_monitor->udev, "multicast kernel netlink message from pid %d ignored\n",
+				     snl.nl_pid);
+				return NULL;
+			}
+		}
+	}
+
+	cmsg = CMSG_FIRSTHDR(&smsg);
+	if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
+		info(udev_monitor->udev, "no sender credentials received, message ignored\n");
+		return NULL;
+	}
+
+	cred = (struct ucred *)CMSG_DATA(cmsg);
+	if (cred->uid != 0) {
+		info(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)) {
+			err(udev_monitor->udev, "ignored a message from an invalid release of udevadm (%x != %x)\n",
+			    nlh->magic, htonl(UDEV_MONITOR_MAGIC));
+			return NULL;
+		}
+		if (nlh->properties_off+32 > 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) {
+			info(udev_monitor->udev, "invalid message length\n");
+			return NULL;
+		}
+
+		/* check message header */
+		if (strstr(buf, "@/") == NULL) {
+			info(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) {
+		info(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;
+
+	blen = udev_device_get_properties_monitor_buf(udev_device, &buf);
+	if (blen < 32)
+		return -EINVAL;
+
+	if (udev_monitor->sun.sun_family != 0) {
+		struct msghdr smsg;
+		struct iovec iov[2];
+		const char *action;
+		char header[2048];
+		char *s;
+
+		/* header <action>@<devpath> */
+		action = udev_device_get_action(udev_device);
+		if (action == NULL)
+			return -EINVAL;
+		s = header;
+		if (util_strpcpyl(&s, sizeof(header), action, "@", udev_device_get_devpath(udev_device), NULL) == 0)
+			return -EINVAL;
+		iov[0].iov_base = header;
+		iov[0].iov_len = (s - header)+1;
+
+		/* add properties list */
+		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;
+		smsg.msg_name = &udev_monitor->sun;
+		smsg.msg_namelen = udev_monitor->addrlen;
+		count = sendmsg(udev_monitor->sock, &smsg, 0);
+		info(udev_monitor->udev, "passed %zi bytes to socket monitor %p\n", count, udev_monitor);
+		return count;
+	}
+
+	if (udev_monitor->snl.nl_family != 0) {
+		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;
+
+		/* 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);
+		info(udev_monitor->udev, "passed %zi bytes to netlink monitor %p\n", count, udev_monitor);
+		return count;
+	}
+
+	return -EINVAL;
+}
+
+/**
+ * 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 filer 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.
+ */
+UDEV_EXPORT 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->udev,
+				&udev_monitor->filter_subsystem_list, subsystem, devtype, 0) == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+/**
+ * udev_monitor_filter_add_match_tag:
+ * @udev_monitor: the monitor
+ * @tag: the name of a tag
+ *
+ * This filer 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.
+ */
+UDEV_EXPORT 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->udev,
+				&udev_monitor->filter_tag_list, tag, NULL, 0) == 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.
+ */
+UDEV_EXPORT int udev_monitor_filter_remove(struct udev_monitor *udev_monitor)
+{
+	static struct sock_fprog filter = { 0, NULL };
+
+	udev_list_cleanup_entries(udev_monitor->udev, &udev_monitor->filter_subsystem_list);
+	return setsockopt(udev_monitor->sock, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter));
+}
diff --git a/src/libudev-legacy/libudev-private.h b/src/libudev-legacy/libudev-private.h
new file mode 100644
index 0000000000..315ca3d700
--- /dev/null
+++ b/src/libudev-legacy/libudev-private.h
@@ -0,0 +1,253 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#ifndef _LIBUDEV_PRIVATE_H_
+#define _LIBUDEV_PRIVATE_H_
+
+#include <syslog.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include "libudev.h"
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#define READ_END				0
+#define WRITE_END				1
+
+static inline void __attribute__((always_inline, format(printf, 2, 3)))
+udev_log_null(struct udev *udev, const char *format, ...) {}
+
+#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)
+
+#ifdef ENABLE_LOGGING
+#  ifdef ENABLE_DEBUG
+#    define dbg(udev, arg...) udev_log_cond(udev, LOG_DEBUG, ## arg)
+#  else
+#    define dbg(udev, arg...) udev_log_null(udev, ## arg)
+#  endif
+#  define info(udev, arg...) udev_log_cond(udev, LOG_INFO, ## arg)
+#  define err(udev, arg...) udev_log_cond(udev, LOG_ERR, ## arg)
+#else
+#  define dbg(udev, arg...) udev_log_null(udev, ## arg)
+#  define info(udev, arg...) udev_log_null(udev, ## arg)
+#  define err(udev, arg...) udev_log_null(udev, ## arg)
+#endif
+
+#define UDEV_EXPORT __attribute__ ((visibility("default")))
+
+static inline void udev_log_init(const char *program_name)
+{
+	openlog(program_name, LOG_PID | LOG_CONS, LOG_DAEMON);
+}
+
+static inline void udev_log_close(void)
+{
+	closelog();
+}
+
+/* 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)));
+const char *udev_get_rules_path(struct udev *udev);
+const char *udev_get_run_config_path(struct udev *udev);
+const char *udev_set_run_path(struct udev *udev, const char *path);
+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);
+struct udev_device *udev_device_new_from_id_filename(struct udev *udev, char *id);
+mode_t udev_device_get_devnode_mode(struct udev_device *udev_device);
+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, int unique);
+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_knodename(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);
+int udev_device_has_tag(struct udev_device *udev_device, const char *tag);
+int udev_device_get_timeout(struct udev_device *udev_device);
+unsigned long long udev_device_get_usec_initialized(struct udev_device *udev_device);
+void udev_device_set_usec_initialized(struct udev_device *udev_device, unsigned long long 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-ctrl.c - daemon runtime setup */
+struct udev_ctrl;
+struct udev_ctrl *udev_ctrl_new_from_socket(struct udev *udev, const char *socket_path);
+struct udev_ctrl *udev_ctrl_new_from_socket_fd(struct udev *udev, const char *socket_path, int fd);
+int udev_ctrl_enable_receiving(struct udev_ctrl *uctrl);
+struct udev_ctrl *udev_ctrl_ref(struct udev_ctrl *uctrl);
+struct udev_ctrl *udev_ctrl_unref(struct udev_ctrl *uctrl);
+struct udev *udev_ctrl_get_udev(struct udev_ctrl *uctrl);
+int udev_ctrl_get_fd(struct udev_ctrl *uctrl);
+int udev_ctrl_send_set_log_level(struct udev_ctrl *uctrl, int priority, int timeout);
+int udev_ctrl_send_stop_exec_queue(struct udev_ctrl *uctrl, int timeout);
+int udev_ctrl_send_start_exec_queue(struct udev_ctrl *uctrl, int timeout);
+int udev_ctrl_send_reload_rules(struct udev_ctrl *uctrl, int timeout);
+int udev_ctrl_send_ping(struct udev_ctrl *uctrl, int timeout);
+int udev_ctrl_send_exit(struct udev_ctrl *uctrl, int timeout);
+int udev_ctrl_send_set_env(struct udev_ctrl *uctrl, const char *key, int timeout);
+int udev_ctrl_send_set_children_max(struct udev_ctrl *uctrl, int count, int timeout);
+struct udev_ctrl_connection;
+struct udev_ctrl_connection *udev_ctrl_get_connection(struct udev_ctrl *uctrl);
+struct udev_ctrl_connection *udev_ctrl_connection_ref(struct udev_ctrl_connection *conn);
+struct udev_ctrl_connection *udev_ctrl_connection_unref(struct udev_ctrl_connection *conn);
+struct udev_ctrl_msg;
+struct udev_ctrl_msg *udev_ctrl_receive_msg(struct udev_ctrl_connection *conn);
+struct udev_ctrl_msg *udev_ctrl_msg_ref(struct udev_ctrl_msg *ctrl_msg);
+struct udev_ctrl_msg *udev_ctrl_msg_unref(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_set_log_level(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_stop_exec_queue(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_start_exec_queue(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_reload_rules(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_ping(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_exit(struct udev_ctrl_msg *ctrl_msg);
+const char *udev_ctrl_get_set_env(struct udev_ctrl_msg *ctrl_msg);
+int udev_ctrl_get_set_children_max(struct udev_ctrl_msg *ctrl_msg);
+
+/* libudev-list.c */
+enum udev_list_flags {
+	UDEV_LIST_NONE =        0,
+	UDEV_LIST_UNIQUE =      1,
+	UDEV_LIST_SORT =        1 << 1,
+};
+struct udev_list_node {
+	struct udev_list_node *next, *prev;
+};
+#define UDEV_LIST(list) struct udev_list_node list = { &(list), &(list) }
+void udev_list_init(struct udev_list_node *list);
+int udev_list_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)
+struct udev_list_entry *udev_list_entry_add(struct udev *udev, struct udev_list_node *list,
+						   const char *name, const char *value, unsigned int flags);
+void udev_list_entry_delete(struct udev_list_entry *entry);
+void udev_list_entry_remove(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_node *list);
+void udev_list_cleanup_entries(struct udev *udev, struct udev_list_node *name_list);
+struct udev_list_entry *udev_list_get_entry(struct udev_list_node *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);
+int udev_queue_export_device_failed(struct udev_queue_export *udev_queue_export, struct udev_device *udev_device);
+
+/* 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_subsystem(struct udev *udev, const char *syspath, char *subsystem, size_t size);
+ssize_t util_get_sys_driver(struct udev *udev, const char *syspath, char *driver, 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);
+size_t util_path_decode(char *s);
+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 udev_util_replace_whitespace(const char *str, char *to, size_t len);
+int udev_util_replace_chars(char *str, const char *white);
+int udev_util_encode_string(const char *str, char *str_enc, size_t len);
+unsigned int util_string_hash32(const char *key);
+uint64_t util_string_bloom64(const char *str);
+
+/* libudev-util-private.c */
+int util_create_path(struct udev *udev, const char *path);
+int util_create_path_selinux(struct udev *udev, const char *path);
+int util_delete_path(struct udev *udev, const char *path);
+int util_unlink_secure(struct udev *udev, const char *filename);
+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);
+unsigned long long now_usec(void);
+
+/* libudev-selinux-private.c */
+#ifndef WITH_SELINUX
+static inline void udev_selinux_init(struct udev *udev) {}
+static inline void udev_selinux_exit(struct udev *udev) {}
+static inline void udev_selinux_lsetfilecon(struct udev *udev, const char *file, unsigned int mode) {}
+static inline void udev_selinux_setfscreatecon(struct udev *udev, const char *file, unsigned int mode) {}
+static inline void udev_selinux_setfscreateconat(struct udev *udev, int dfd, const char *file, unsigned int mode) {}
+static inline void udev_selinux_resetfscreatecon(struct udev *udev) {}
+#else
+void udev_selinux_init(struct udev *udev);
+void udev_selinux_exit(struct udev *udev);
+void udev_selinux_lsetfilecon(struct udev *udev, const char *file, unsigned int mode);
+void udev_selinux_setfscreatecon(struct udev *udev, const char *file, unsigned int mode);
+void udev_selinux_setfscreateconat(struct udev *udev, int dfd, const char *file, unsigned int mode);
+void udev_selinux_resetfscreatecon(struct udev *udev);
+#endif
+
+#endif
diff --git a/src/libudev-legacy/libudev-queue.c b/src/libudev-legacy/libudev-queue.c
new file mode 100644
index 0000000000..73e7fb23aa
--- /dev/null
+++ b/src/libudev-legacy/libudev-queue.c
@@ -0,0 +1,515 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2009 Alan Jenkins <alan-jenkins@tuffmail.co.uk>
+ *
+ * This library 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.
+ */
+
+#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_node queue_list;
+	struct udev_list_node failed_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.
+ **/
+UDEV_EXPORT 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_queue->queue_list);
+	udev_list_init(&udev_queue->failed_list);
+	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.
+ **/
+UDEV_EXPORT 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.
+ **/
+UDEV_EXPORT void udev_queue_unref(struct udev_queue *udev_queue)
+{
+	if (udev_queue == NULL)
+		return;
+	udev_queue->refcount--;
+	if (udev_queue->refcount > 0)
+		return;
+	udev_list_cleanup_entries(udev_queue->udev, &udev_queue->queue_list);
+	udev_list_cleanup_entries(udev_queue->udev, &udev_queue->failed_list);
+	free(udev_queue);
+}
+
+/**
+ * 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.
+ **/
+UDEV_EXPORT 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)
+{
+	char filename[UTIL_PATH_SIZE];
+	unsigned long long int seqnum;
+	int fd;
+	char buf[32];
+	ssize_t len;
+
+	util_strscpyl(filename, sizeof(filename), udev_get_sys_path(udev), "/kernel/uevent_seqnum", NULL);
+	fd = open(filename, 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
+ *
+ * Returns: the current kernel event sequence number.
+ **/
+UDEV_EXPORT 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);
+	dbg(udev_queue->udev, "seqnum=%llu\n", seqnum);
+	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[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[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)
+{
+	char filename[UTIL_PATH_SIZE];
+	FILE *queue_file;
+
+	util_strscpyl(filename, sizeof(filename), udev_get_run_path(udev_queue->udev), "/queue.bin", NULL);
+	queue_file = fopen(filename, "re");
+	if (queue_file == NULL)
+		return NULL;
+
+	if (udev_queue_read_seqnum(queue_file, seqnum_start) < 0) {
+		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
+ *
+ * Returns: the last known udev event sequence number.
+ **/
+UDEV_EXPORT 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
+ *
+ * Returns: a flag indicating if udev is active.
+ **/
+UDEV_EXPORT 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
+ *
+ * Returns: a flag indicating if udev is currently handling events.
+ **/
+UDEV_EXPORT 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) {
+		dbg(udev_queue->udev, "queue is not empty\n");
+		goto out;
+	}
+
+	seqnum_kernel = udev_queue_get_kernel_seqnum(udev_queue);
+	if (seqnum_udev < seqnum_kernel) {
+		dbg(udev_queue->udev, "queue is empty but kernel events still pending [%llu]<->[%llu]\n",
+					seqnum_kernel, seqnum_udev);
+		goto out;
+	}
+
+	dbg(udev_queue->udev, "queue is empty\n");
+	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
+ *
+ * Returns: a flag indicating if any of the sequence numbers in the given range is currently active.
+ **/
+UDEV_EXPORT 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
+ *
+ * Returns: a flag indicating if the given sequence number is currently active.
+ **/
+UDEV_EXPORT 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;
+
+	dbg(udev_queue->udev, "seqnum: %llu finished\n", seqnum);
+	return 1;
+}
+
+/**
+ * udev_queue_get_queued_list_entry:
+ * @udev_queue: udev queue context
+ *
+ * Returns: the first entry of the list of queued events.
+ **/
+UDEV_EXPORT 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_entries(udev_queue->udev, &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_strpcpyl(&s, sizeof(syspath), udev_get_sys_path(udev_queue->udev), NULL);
+		len = udev_queue_read_devpath(queue_file, s, l);
+		if (len < 0)
+			break;
+
+		if (len > 0) {
+			udev_list_entry_add(udev_queue->udev, &udev_queue->queue_list, syspath, seqnum_str, 0);
+		} 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);
+}
+
+/**
+ * udev_queue_get_failed_list_entry:
+ * @udev_queue: udev queue context
+ *
+ * Returns: the first entry of the list of recorded failed events.
+ **/
+UDEV_EXPORT struct udev_list_entry *udev_queue_get_failed_list_entry(struct udev_queue *udev_queue)
+{
+	char path[UTIL_PATH_SIZE];
+	DIR *dir;
+	struct dirent *dent;
+
+	if (udev_queue == NULL)
+		return NULL;
+	udev_list_cleanup_entries(udev_queue->udev, &udev_queue->failed_list);
+	util_strscpyl(path, sizeof(path), udev_get_run_path(udev_queue->udev), "/failed", NULL);
+	dir = opendir(path);
+	if (dir == NULL)
+		return NULL;
+	for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+		char filename[UTIL_PATH_SIZE];
+		char syspath[UTIL_PATH_SIZE];
+		char *s;
+		size_t l;
+		ssize_t len;
+		struct stat statbuf;
+
+		if (dent->d_name[0] == '.')
+			continue;
+		s = syspath;
+		l = util_strpcpyl(&s, sizeof(syspath), udev_get_sys_path(udev_queue->udev), NULL);
+		len = readlinkat(dirfd(dir), dent->d_name, s, l);
+		if (len <= 0 || (size_t)len == l)
+			continue;
+		s[len] = '\0';
+		dbg(udev_queue->udev, "found '%s' [%s]\n", syspath, dent->d_name);
+		util_strscpyl(filename, sizeof(filename), syspath, "/uevent", NULL);
+		if (stat(filename, &statbuf) != 0)
+			continue;
+		udev_list_entry_add(udev_queue->udev, &udev_queue->failed_list, syspath, NULL, 0);
+	}
+	closedir(dir);
+	return udev_list_get_entry(&udev_queue->failed_list);
+}
diff --git a/src/libudev-legacy/libudev-util.c b/src/libudev-legacy/libudev-util.c
new file mode 100644
index 0000000000..48eea0b898
--- /dev/null
+++ b/src/libudev-legacy/libudev-util.c
@@ -0,0 +1,568 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2009 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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 <sys/stat.h>
+
+#include "libudev.h"
+#include "libudev-private.h"
+
+static ssize_t get_sys_link(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];
+	dbg(udev, "resolved link to: '%s'\n", pos);
+	return util_strscpy(value, size, pos);
+}
+
+ssize_t util_get_sys_subsystem(struct udev *udev, const char *syspath, char *subsystem, size_t size)
+{
+	return get_sys_link(udev, "subsystem", syspath, subsystem, size);
+}
+
+ssize_t util_get_sys_driver(struct udev *udev, const char *syspath, char *driver, size_t size)
+{
+	return get_sys_link(udev, "driver", syspath, driver, size);
+}
+
+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;
+
+	len = readlink(syspath, link_target, sizeof(link_target));
+	if (len <= 0 || len == (ssize_t)sizeof(link_target))
+		return -1;
+	link_target[len] = '\0';
+	dbg(udev, "path link '%s' points to '%s'\n", syspath, link_target);
+
+	for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
+		;
+	dbg(udev, "base '%s', tail '%s', back %i\n", syspath, &link_target[back * 3], back);
+	for (i = 0; i <= back; i++) {
+		base = strrchr(syspath, '/');
+		if (base == NULL)
+			return -1;
+		base[0] = '\0';
+	}
+	dbg(udev, "after moving back '%s'\n", syspath);
+	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 (strncmp(priority, "err", 3) == 0)
+		return LOG_ERR;
+	if (strncmp(priority, "info", 4) == 0)
+		return LOG_INFO;
+	if (strncmp(priority, "debug", 5) == 0)
+		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;
+}
+
+size_t util_path_decode(char *s)
+{
+	size_t i, j;
+
+	for (i = 0, j = 0; s[i] != '\0'; j++) {
+		if (memcmp(&s[i], "\\x2f", 4) == 0) {
+			s[j] = '/';
+			i += 4;
+		} else if (memcmp(&s[i], "\\x5c", 4) == 0) {
+			s[j] = '\\';
+			i += 4;
+		} else {
+			s[j] = s[i];
+			i++;
+		}
+	}
+	s[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 udev_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 udev_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;
+}
+
+/**
+ * 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 hex value prefixed by '\x'.
+ *
+ * Returns: 0 if the entire string was copied, non-zero otherwise.
+ **/
+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;
+}
+
+#define USEC_PER_SEC  1000000ULL
+#define NSEC_PER_USEC 1000ULL
+unsigned long long now_usec(void)
+{
+	struct timespec ts;
+
+	if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0)
+		return 0;
+	return (unsigned long long) ts.tv_sec * USEC_PER_SEC +
+	       (unsigned long long) ts.tv_nsec / NSEC_PER_USEC;
+}
diff --git a/src/libudev-legacy/libudev.c b/src/libudev-legacy/libudev.c
new file mode 100644
index 0000000000..e131d8cbec
--- /dev/null
+++ b/src/libudev-legacy/libudev.c
@@ -0,0 +1,467 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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 "libudev.h"
+#include "libudev-private.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;
+	char *sys_path;
+	char *dev_path;
+	char *rules_path;
+	char *run_config_path;
+	char *run_path;
+	struct udev_list_node 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
+ **/
+UDEV_EXPORT 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.
+ **/
+UDEV_EXPORT void udev_set_userdata(struct udev *udev, void *userdata)
+{
+	if (udev == NULL)
+		return;
+	udev->userdata = userdata;
+}
+
+static char *set_value(char **s, const char *v)
+{
+	free(*s);
+	*s = strdup(v);
+	util_remove_trailing_chars(*s, '/');
+	return *s;
+}
+
+/**
+ * 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
+ **/
+UDEV_EXPORT struct udev *udev_new(void)
+{
+	struct udev *udev;
+	const char *env;
+	char *config_file = NULL;
+	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->properties_list);
+
+	/* custom config file */
+	env = getenv("UDEV_CONFIG_FILE");
+	if (env != NULL) {
+		udev_add_property(udev, "UDEV_CONFIG_FILE", udev->dev_path);
+		if (set_value(&config_file, env) == NULL)
+			goto err;
+	}
+
+	/* default config file */
+	if (config_file == NULL)
+		config_file = strdup(UDEV_CONF_FILE);
+	if (config_file == NULL)
+		goto err;
+
+	f = fopen(config_file, "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) {
+				err(udev, "missing <key>=<value> in '%s'[%i], skip line\n", config_file, 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]) {
+					err(udev, "inconsistent quoting in '%s'[%i], skip line\n", config_file, line_nr);
+					continue;
+				}
+				val[len-1] = '\0';
+				val++;
+			}
+
+			if (strcmp(key, "udev_log") == 0) {
+				udev_set_log_priority(udev, util_log_priority(val));
+				continue;
+			}
+			if (strcmp(key, "udev_root") == 0) {
+				set_value(&udev->dev_path, val);
+				continue;
+			}
+			if (strcmp(key, "udev_run") == 0) {
+				set_value(&udev->run_config_path, val);
+				continue;
+			}
+			if (strcmp(key, "udev_rules") == 0) {
+				set_value(&udev->rules_path, val);
+				continue;
+			}
+		}
+		fclose(f);
+	}
+
+	/* environment overwrites config */
+	env = getenv("UDEV_LOG");
+	if (env != NULL)
+		udev_set_log_priority(udev, util_log_priority(env));
+
+	env = getenv("UDEV_ROOT");
+	if (env != NULL) {
+		set_value(&udev->dev_path, env);
+		udev_add_property(udev, "UDEV_ROOT", udev->dev_path);
+	}
+
+	env = getenv("SYSFS_PATH");
+	if (env != NULL) {
+		set_value(&udev->sys_path, env);
+		udev_add_property(udev, "SYSFS_PATH", udev->sys_path);
+	}
+
+	/* set defaults */
+	if (udev->dev_path == NULL)
+		if (set_value(&udev->dev_path, "/dev") == NULL)
+			goto err;
+
+	if (udev->sys_path == NULL)
+		if (set_value(&udev->sys_path, "/sys") == NULL)
+			goto err;
+
+	if (udev->run_config_path == NULL)
+		if (set_value(&udev->run_config_path, "/run/udev") == NULL)
+			goto err;
+
+	dbg(udev, "context %p created\n", udev);
+	dbg(udev, "log_priority=%d\n", udev->log_priority);
+	dbg(udev, "config_file='%s'\n", config_file);
+	dbg(udev, "dev_path='%s'\n", udev->dev_path);
+	dbg(udev, "sys_path='%s'\n", udev->sys_path);
+	dbg(udev, "run_path='%s'\n", udev->run_config_path);
+	if (udev->rules_path != NULL)
+		dbg(udev, "rules_path='%s'\n", udev->rules_path);
+	free(config_file);
+	return udev;
+err:
+	free(config_file);
+	err(udev, "context creation failed\n");
+	udev_unref(udev);
+	return NULL;
+}
+
+/**
+ * udev_ref:
+ * @udev: udev library context
+ *
+ * Take a reference of the udev library context.
+ *
+ * Returns: the passed udev library context
+ **/
+UDEV_EXPORT 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.
+ *
+ **/
+UDEV_EXPORT void udev_unref(struct udev *udev)
+{
+	if (udev == NULL)
+		return;
+	udev->refcount--;
+	if (udev->refcount > 0)
+		return;
+	udev_list_cleanup_entries(udev, &udev->properties_list);
+	free(udev->dev_path);
+	free(udev->sys_path);
+	free(udev->rules_path);
+	free(udev->run_path);
+	free(udev->run_config_path);
+	dbg(udev, "context %p released\n", udev);
+	free(udev);
+}
+
+/**
+ * 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.
+ *
+ **/
+UDEV_EXPORT 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;
+	info(udev, "custom logging function %p registered\n", udev);
+}
+
+/**
+ * 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
+ **/
+UDEV_EXPORT 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.
+ **/
+UDEV_EXPORT 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);
+}
+
+const char *udev_get_rules_path(struct udev *udev)
+{
+	return udev->rules_path;
+}
+
+/**
+ * udev_get_sys_path:
+ * @udev: udev library context
+ *
+ * Retrieve the sysfs mount point. The default is "/sys". For
+ * testing purposes, it can be overridden with the environment
+ * variable SYSFS_PATH.
+ *
+ * Returns: the sys mount point
+ **/
+UDEV_EXPORT const char *udev_get_sys_path(struct udev *udev)
+{
+	if (udev == NULL)
+		return NULL;
+	return udev->sys_path;
+}
+
+/**
+ * udev_get_dev_path:
+ * @udev: udev library context
+ *
+ * Retrieve the device directory path. The default value is "/dev",
+ * the actual value may be overridden in the udev configuration
+ * file.
+ *
+ * Returns: the device directory path
+ **/
+UDEV_EXPORT const char *udev_get_dev_path(struct udev *udev)
+{
+	if (udev == NULL)
+		return NULL;
+	return udev->dev_path;
+}
+
+const char *udev_get_run_config_path(struct udev *udev)
+{
+	return udev->run_config_path;
+}
+
+/**
+ * udev_get_run_path:
+ * @udev: udev library context
+ *
+ * Retrieve the udev runtime directory path. The default is "/run/udev".
+ *
+ * Returns: the runtime directory path
+ **/
+UDEV_EXPORT const char *udev_get_run_path(struct udev *udev)
+{
+	if (udev->run_path != NULL)
+		return udev->run_path;
+
+	/* check if configured path exists */
+	if (access(udev->run_config_path, F_OK) < 0) {
+		char filename[UTIL_PATH_SIZE];
+
+		/* fall back to /dev/.udev if that exists */
+		util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev", NULL);
+		if (access(filename, F_OK) >= 0)
+			if (set_value(&udev->run_path, filename) != NULL)
+				return udev->run_path;
+	}
+
+	/* use default path */
+	set_value(&udev->run_path, udev->run_config_path);
+	if (udev->run_path == NULL)
+		return udev->run_config_path;
+	return udev->run_path;
+}
+
+const char *udev_set_run_path(struct udev *udev, const char *path)
+{
+	return set_value(&udev->run_path, path);
+}
+
+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, &udev->properties_list, key, value, UDEV_LIST_UNIQUE);
+}
+
+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-legacy/libudev.h b/src/libudev-legacy/libudev.h
new file mode 100644
index 0000000000..021ef9e8c0
--- /dev/null
+++ b/src/libudev-legacy/libudev.h
@@ -0,0 +1,180 @@
+/*
+ * libudev - interface to udev device information
+ *
+ * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library 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.
+ */
+
+#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);
+void 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);
+const char *udev_get_sys_path(struct udev *udev);
+const char *udev_get_dev_path(struct udev *udev);
+const char *udev_get_run_path(struct udev *udev);
+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);
+void 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_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);
+
+/*
+ * udev_monitor
+ *
+ * access to kernel uevents and udev events
+ */
+struct udev_monitor;
+struct udev_monitor *udev_monitor_ref(struct udev_monitor *udev_monitor);
+void 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);
+/* custom socket (use netlink and filters instead) */
+struct udev_monitor *udev_monitor_new_from_socket(struct udev *udev, const char *socket_path);
+/* 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);
+void 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_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);
+void 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);
+struct udev_list_entry *udev_queue_get_failed_list_entry(struct udev_queue *udev_queue);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif