chiark / gitweb /
libudev: udev_device_get_sysattr_value() return syspath of custom links
[elogind.git] / libudev / libudev-device.c
index 9965972b3288c5c1a58b5273e0d7347f86a6b822..991398c76d4df2c22a9267c3b515658feee8395e 100644 (file)
@@ -1,7 +1,7 @@
 /*
  * libudev - interface to udev device information
  *
- * Copyright (C) 2008-2009 Kay Sievers <kay.sievers@vrfy.org>
+ * 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
 #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"
@@ -30,7 +35,7 @@
  * 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 subsytem.
+ * a unique name inside that subsystem.
  */
 
 /**
@@ -46,105 +51,482 @@ struct udev_device {
        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_list;
+       struct udev_list devlinks_list;
+       struct udev_list properties_list;
+       struct udev_list sysattr_value_list;
+       struct udev_list sysattr_list;
+       struct udev_list tags_list;
        unsigned long long int seqnum;
-       int event_timeout;
+       unsigned long long int usec_initialized;
        int timeout;
-       int num_fake_partitions;
        int devlink_priority;
        int refcount;
        dev_t devnum;
+       int ifindex;
        int watch_handle;
-       unsigned int parent_set:1;
-       unsigned int subsystem_set:1;
-       unsigned int devtype_set:1;
-       unsigned int devlinks_uptodate:1;
-       unsigned int envp_uptodate:1;
-       unsigned int driver_set:1;
-       unsigned int info_loaded:1;
-       unsigned int ignore_remove:1;
+       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;
 };
 
-static size_t devpath_to_db_path(struct udev *udev, const char *devpath, char *filename, size_t len)
+/**
+ * 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)
 {
-       char *s;
-       size_t l;
+       if (udev_device == NULL)
+               return 0;
+       return udev_device->seqnum;
+}
 
-       s = filename;
-       l = util_strpcpyl(&s, len, udev_get_dev_path(udev), "/.udev/db/", NULL);
-       return util_path_encode(devpath, s, l);
+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_read_db(struct udev_device *udev_device)
+int udev_device_get_ifindex(struct udev_device *udev_device)
 {
-       struct stat stats;
-       char filename[UTIL_PATH_SIZE];
-       char line[UTIL_LINE_SIZE];
-       FILE *f;
+       if (!udev_device->info_loaded)
+               udev_device_read_uevent_file(udev_device);
+       return udev_device->ifindex;
+}
 
-       devpath_to_db_path(udev_device->udev, udev_device->devpath, filename, sizeof(filename));
+static int udev_device_set_ifindex(struct udev_device *udev_device, int ifindex)
+{
+       char num[32];
 
-       if (lstat(filename, &stats) != 0) {
-               dbg(udev_device->udev, "no db file to read %s: %m\n", filename);
-               return -1;
+       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_core_link_value(udev_device->udev, "driver", udev_device->syspath, driver, sizeof(driver)) > 0)
+                       udev_device->driver = strdup(driver);
        }
-       if ((stats.st_mode & S_IFMT) == S_IFLNK) {
-               char target[UTIL_PATH_SIZE];
-               char devnode[UTIL_PATH_SIZE];
-               int target_len;
-               char *next;
+       return udev_device->driver;
+}
 
-               target_len = readlink(filename, target, sizeof(target));
-               if (target_len > 0)
-                       target[target_len] = '\0';
-               else {
-                       dbg(udev_device->udev, "error reading db link %s: %m\n", filename);
-                       return -1;
+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_core_link_value(udev_device->udev, "subsystem", udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
+                       udev_device_set_subsystem(udev_device, subsystem);
+                       return udev_device->subsystem;
+               }
+               /* implicit names */
+               if (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;
+}
 
-               next = strchr(target, ' ');
-               if (next != NULL) {
+mode_t udev_device_get_devnode_mode(struct udev_device *udev_device)
+{
+       if (!udev_device->info_loaded)
+               udev_device_read_uevent_file(udev_device);
+       return udev_device->devnode_mode;
+}
+
+static int udev_device_set_devnode_mode(struct udev_device *udev_device, mode_t mode)
+{
+       char num[32];
+
+       udev_device->devnode_mode = mode;
+       snprintf(num, sizeof(num), "%#o", mode);
+       udev_device_add_property(udev_device, "DEVMODE", num);
+       return 0;
+}
+
+struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
+{
+       udev_device->envp_uptodate = false;
+       if (value == NULL) {
+               struct udev_list_entry *list_entry;
+
+               list_entry = udev_device_get_properties_list_entry(udev_device);
+               list_entry = udev_list_entry_get_by_name(list_entry, key);
+               if (list_entry != NULL)
+                       udev_list_entry_delete(list_entry);
+               return NULL;
+       }
+       return udev_list_entry_add(&udev_device->properties_list, key, value);
+}
+
+static struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
+{
+       char name[UTIL_LINE_SIZE];
+       char *val;
+
+       util_strscpy(name, sizeof(name), property);
+       val = strchr(name, '=');
+       if (val == NULL)
+               return NULL;
+       val[0] = '\0';
+       val = &val[1];
+       if (val[0] == '\0')
+               val = NULL;
+       return udev_device_add_property(udev_device, name, val);
+}
+
+/*
+ * parse property string, and if needed, update internal values accordingly
+ *
+ * udev_device_add_property_from_string_parse_finish() needs to be
+ * called after adding properties, and its return value checked
+ *
+ * udev_device_set_info_loaded() needs to be set, to avoid trying
+ * to use a device without a DEVPATH set
+ */
+void udev_device_add_property_from_string_parse(struct udev_device *udev_device, const char *property)
+{
+       if (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';
-                       next = &next[1];
+                       udev_device_add_devlink(udev_device, slink, 0);
+                       slink = &next[1];
+                       next = strchr(slink, ' ');
                }
-               util_strscpyl(devnode, sizeof(devnode), udev_get_dev_path(udev_device->udev), "/", target, NULL);
-               udev_device_set_devnode(udev_device, devnode);
-               while (next != NULL) {
-                       char devlink[UTIL_PATH_SIZE];
-                       const char *lnk;
+               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;
 
-                       lnk = next;
-                       next = strchr(next, ' ');
-                       if (next != NULL) {
+               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 = &next[1];
+                               next++;
+                               udev_device_add_tag(udev_device, tag);
                        }
-                       util_strscpyl(devlink, sizeof(devlink), udev_get_dev_path(udev_device->udev), "/", lnk, NULL);
-                       udev_device_add_devlink(udev_device, devlink);
                }
-               info(udev_device->udev, "device %p filled with db symlink data '%s'\n", udev_device, udev_device->devnode);
-               return 0;
+       } else if (strncmp(property, "USEC_INITIALIZED=", 19) == 0) {
+               udev_device_set_usec_initialized(udev_device, strtoull(&property[19], NULL, 10));
+       } 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;
 
-       f = fopen(filename, "r");
+       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) {
-               dbg(udev_device->udev, "error reading db file %s: %m\n", filename);
+               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)
@@ -158,26 +540,24 @@ int udev_device_read_db(struct udev_device *udev_device)
                        break;
                case 'S':
                        util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/", val, NULL);
-                       udev_device_add_devlink(udev_device, filename);
+                       udev_device_add_devlink(udev_device, filename, 0);
                        break;
                case 'L':
                        udev_device_set_devlink_priority(udev_device, atoi(val));
                        break;
-               case 'T':
-                       udev_device_set_event_timeout(udev_device, atoi(val));
-                       break;
-               case 'A':
-                       udev_device_set_num_fake_partitions(udev_device, atoi(val));
-                       break;
-               case 'R':
-                       udev_device_set_ignore_remove(udev_device, atoi(val));
-                       break;
                case 'E':
-                       udev_device_add_property_from_string(udev_device, val);
+                       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);
@@ -194,10 +574,14 @@ int udev_device_read_uevent_file(struct udev_device *udev_device)
        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, "r");
+       f = fopen(filename, "re");
        if (f == NULL)
                return -1;
+       udev_device->uevent_loaded = true;
 
        while (fgets(line, sizeof(line), f)) {
                char *pos;
@@ -213,28 +597,24 @@ int udev_device_read_uevent_file(struct udev_device *udev_device)
                        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;
 }
 
-static void device_load_info(struct udev_device *device)
-{
-       device->info_loaded = 1;
-       udev_device_read_uevent_file(device);
-       udev_device_read_db(device);
-}
-
 void udev_device_set_info_loaded(struct udev_device *device)
 {
-       device->info_loaded = 1;
+       device->info_loaded = true;
 }
 
 struct udev_device *udev_device_new(struct udev *udev)
@@ -250,10 +630,12 @@ struct udev_device *udev_device_new(struct udev *udev)
                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_list);
-       udev_device->event_timeout = -1;
+       udev_list_init(udev, &udev_device->devlinks_list, true);
+       udev_list_init(udev, &udev_device->properties_list, true);
+       udev_list_init(udev, &udev_device->sysattr_value_list, true);
+       udev_list_init(udev, &udev_device->sysattr_list, false);
+       udev_list_init(udev, &udev_device->tags_list, true);
+       udev_device->timeout = -1;
        udev_device->watch_handle = -1;
        /* copy global properties */
        udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
@@ -270,7 +652,7 @@ struct udev_device *udev_device_new(struct udev *udev)
  * @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 sypath is the absolute
+ * 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
@@ -278,7 +660,7 @@ struct udev_device *udev_device_new(struct udev *udev)
  *
  * Returns: a new udev device, or #NULL, if it does not exist
  **/
-struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
+UDEV_EXPORT struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
 {
        size_t len;
        const char *subdir;
@@ -311,25 +693,7 @@ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *
        util_strscpy(path, sizeof(path), syspath);
        util_resolve_sys_link(udev, path, sizeof(path));
 
-       /* try to resolve the silly block layout if needed */
-       if (strncmp(&path[len], "/block/", 7) == 0) {
-               char block[UTIL_PATH_SIZE];
-               char part[UTIL_PATH_SIZE];
-
-               util_strscpy(block, sizeof(block), path);
-               pos = strrchr(block, '/');
-               if (pos == NULL)
-                       return NULL;
-               util_strscpy(part, sizeof(part), pos);
-               pos[0] = '\0';
-               if (util_resolve_sys_link(udev, block, sizeof(block)) == 0)
-                       util_strscpyl(path, sizeof(path), block, part, NULL);
-       }
-
-       /* path exists in sys */
-       if (strncmp(&syspath[len], "/devices/", 9) == 0 ||
-           strncmp(&syspath[len], "/class/", 7) == 0 ||
-           strncmp(&syspath[len], "/block/", 7) == 0) {
+       if (strncmp(&path[len], "/devices/", 9) == 0) {
                char file[UTIL_PATH_SIZE];
 
                /* all "devices" require a "uevent" file */
@@ -363,23 +727,19 @@ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *
  * @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. Character and block device numbers
- * are not unique across the two types, they do not share the same
- * range of numbers.
+ * 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
  **/
-struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
+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;
-       struct udev_enumerate *udev_enumerate;
-       struct udev_list_entry *list_entry;
-       struct udev_device *device = NULL;
 
        if (type == 'b')
                type_str = "block";
@@ -388,59 +748,83 @@ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, de
        else
                return NULL;
 
-       /* /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));
-       if (util_resolve_sys_link(udev, path, sizeof(path)) == 0)
-               return udev_device_new_from_syspath(udev, path);
+       /* 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);
+}
 
-       udev_enumerate = udev_enumerate_new(udev);
-       if (udev_enumerate == NULL)
-               return NULL;
+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;
 
-       /* fallback to search sys devices for the major/minor */
-       if (type == 'b')
-               udev_enumerate_add_match_subsystem(udev_enumerate, "block");
-       else if (type == 'c')
-               udev_enumerate_add_nomatch_subsystem(udev_enumerate, "block");
-       udev_enumerate_scan_devices(udev_enumerate);
-       udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
-               struct udev_device *device_loop;
-
-               device_loop = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
-               if (device_loop != NULL) {
-                       if (udev_device_get_devnum(device_loop) == devnum) {
-                               if (type == 'b' && strcmp(udev_device_get_subsystem(device_loop), "block") != 0)
-                                       continue;
-                               if (type == 'c' && strcmp(udev_device_get_subsystem(device_loop), "block") == 0)
-                                       continue;
-                               device = device_loop;
-                               break;
-                       }
-                       udev_device_unref(device_loop);
+       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_enumerate_unref(udev_enumerate);
-       return device;
 }
 
 /**
  * udev_device_new_from_subsystem_sysname:
  * @udev: udev library context
- * @subsystem: the subsytem of the device
+ * @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 subsytem and name string of the device, like "mem",
- * "zero", or "block", "sda".
+ * 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
  **/
-struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
+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;
@@ -510,26 +894,51 @@ 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;
 
-       /* follow "device" link in deprecated sys layout */
-       if (strncmp(udev_device->devpath, "/class/", 7) == 0 ||
-           strncmp(udev_device->devpath, "/block/", 7) == 0) {
-               util_strscpyl(path, sizeof(path), udev_device->syspath, "/device", NULL);
-               if (util_resolve_sys_link(udev_device->udev, path, sizeof(path)) == 0) {
-                       udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
-                       if (udev_device_parent != NULL)
-                               return udev_device_parent;
-               }
-       }
-
        util_strscpy(path, sizeof(path), udev_device->syspath);
        subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
-       while (1) {
+       for (;;) {
                char *pos;
 
                pos = strrchr(subdir, '/');
@@ -554,7 +963,7 @@ static struct udev_device *device_new_from_parent(struct udev_device *udev_devic
  * child device, and will be cleaned up when the child device
  * is cleaned up.
  *
- * It is not neccessarily just the upper level directory, empty or not
+ * 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
@@ -562,12 +971,12 @@ static struct udev_device *device_new_from_parent(struct udev_device *udev_devic
  *
  * Returns: a new udev device, or #NULL, if it no parent exist.
  **/
-struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
+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 = 1;
+               udev_device->parent_set = true;
                udev_device->parent_device = device_new_from_parent(udev_device);
        }
        if (udev_device->parent_device != NULL)
@@ -578,13 +987,16 @@ struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
 /**
  * udev_device_get_parent_with_subsystem_devtype:
  * @udev_device: udev device to start searching from
- * @subsystem: the subsytem of the device
+ * @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.
@@ -592,9 +1004,9 @@ struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
  * 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.
+ * Returns: a new udev device, or #NULL if no matching parent exists.
  **/
-struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device, const char *subsystem, const char *devtype)
+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;
 
@@ -627,7 +1039,7 @@ struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_de
  *
  * Returns: the udev library context
  **/
-struct udev *udev_device_get_udev(struct udev_device *udev_device)
+UDEV_EXPORT struct udev *udev_device_get_udev(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -642,7 +1054,7 @@ struct udev *udev_device_get_udev(struct udev_device *udev_device)
  *
  * Returns: the passed udev device
  **/
-struct udev_device *udev_device_ref(struct udev_device *udev_device)
+UDEV_EXPORT struct udev_device *udev_device_ref(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -658,7 +1070,7 @@ struct udev_device *udev_device_ref(struct udev_device *udev_device)
  * the resources of the device will be released.
  *
  **/
-void udev_device_unref(struct udev_device *udev_device)
+UDEV_EXPORT void udev_device_unref(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return;
@@ -672,13 +1084,16 @@ void udev_device_unref(struct udev_device *udev_device)
        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(&udev_device->devlinks_list);
+       udev_list_cleanup(&udev_device->properties_list);
+       udev_list_cleanup(&udev_device->sysattr_value_list);
+       udev_list_cleanup(&udev_device->sysattr_list);
+       udev_list_cleanup(&udev_device->tags_list);
        free(udev_device->action);
        free(udev_device->driver);
        free(udev_device->devpath_old);
        free(udev_device->knodename);
-       udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
+       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);
@@ -694,7 +1109,7 @@ void udev_device_unref(struct udev_device *udev_device)
  *
  * Returns: the devpath of the udev device
  **/
-const char *udev_device_get_devpath(struct udev_device *udev_device)
+UDEV_EXPORT const char *udev_device_get_devpath(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -710,7 +1125,7 @@ const char *udev_device_get_devpath(struct udev_device *udev_device)
  *
  * Returns: the sys path of the udev device
  **/
-const char *udev_device_get_syspath(struct udev_device *udev_device)
+UDEV_EXPORT const char *udev_device_get_syspath(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -723,7 +1138,7 @@ const char *udev_device_get_syspath(struct udev_device *udev_device)
  *
  * Returns: the sys name of the device device
  **/
-const char *udev_device_get_sysname(struct udev_device *udev_device)
+UDEV_EXPORT const char *udev_device_get_sysname(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -736,7 +1151,7 @@ const char *udev_device_get_sysname(struct udev_device *udev_device)
  *
  * Returns: the trailing number of of the device name
  **/
-const char *udev_device_get_sysnum(struct udev_device *udev_device)
+UDEV_EXPORT const char *udev_device_get_sysnum(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -752,74 +1167,26 @@ const char *udev_device_get_sysnum(struct udev_device *udev_device)
  *
  * Returns: the device node file name of the udev device, or #NULL if no device node exists
  **/
-const char *udev_device_get_devnode(struct udev_device *udev_device)
+UDEV_EXPORT const char *udev_device_get_devnode(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
-       if (!udev_device->info_loaded)
-               device_load_info(udev_device);
-       return udev_device->devnode;
-}
+       if (!udev_device->info_loaded) {
+               udev_device_read_uevent_file(udev_device);
+               udev_device_read_db(udev_device, NULL);
+       }
 
-/**
- * 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
- **/
-const char *udev_device_get_subsystem(struct udev_device *udev_device)
-{
-       char subsystem[UTIL_NAME_SIZE];
+       /* 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];
 
-       if (udev_device == NULL)
-               return NULL;
-       if (!udev_device->subsystem_set) {
-               udev_device->subsystem_set = 1;
-               /* read "subsytem" 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;
-               }
+               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->subsystem;
-}
 
-/**
- * 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
- **/
-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 = 1;
-               if (!udev_device->info_loaded)
-                       udev_device_read_uevent_file(udev_device);
-       }
-       return udev_device->devtype;
+       return udev_device->devnode;
 }
 
 /**
@@ -835,19 +1202,19 @@ const char *udev_device_get_devtype(struct udev_device *udev_device)
  *
  * Returns: the first entry of the device node link list
  **/
-struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device)
+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)
-               device_load_info(udev_device);
+               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 = 0;
-       udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
+       udev_device->devlinks_uptodate = false;
+       udev_list_cleanup(&udev_device->devlinks_list);
 }
 
 /**
@@ -856,71 +1223,53 @@ void udev_device_cleanup_devlinks_list(struct 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
- **/
-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)
-               device_load_info(udev_device);
-       if (!udev_device->devlinks_uptodate) {
-               char symlinks[UTIL_PATH_SIZE];
-               struct udev_list_entry *list_entry;
-
-               udev_device->devlinks_uptodate = 1;
-               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);
-               }
-       }
-       return udev_list_get_entry(&udev_device->properties_list);
-}
-
-/**
- * udev_device_get_driver:
- * @udev_device: udev device
- *
- * Returns: the driver string, or #NULL if there is no driver attached.
- **/
-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 = 1;
-               if (util_get_sys_driver(udev_device->udev, udev_device->syspath, driver, sizeof(driver)) > 0)
-                       udev_device->driver = strdup(driver);
-       }
-       return udev_device->driver;
-}
-
-/**
- * udev_device_get_devnum:
- * @udev_device: udev device
+ * 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 device major/minor number.
+ * Returns: the first entry of the property list
  **/
-dev_t udev_device_get_devnum(struct udev_device *udev_device)
+UDEV_EXPORT struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
-               return makedev(0, 0);
-       if (!udev_device->info_loaded)
-               device_load_info(udev_device);
-       return udev_device->devnum;
+               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);
 }
 
 /**
@@ -933,7 +1282,7 @@ dev_t udev_device_get_devnum(struct udev_device *udev_device)
  *
  * Returns: the kernel action value, or #NULL if there is no action value available.
  **/
-const char *udev_device_get_action(struct udev_device *udev_device)
+UDEV_EXPORT const char *udev_device_get_action(struct udev_device *udev_device)
 {
        if (udev_device == NULL)
                return NULL;
@@ -941,19 +1290,45 @@ const char *udev_device_get_action(struct udev_device *udev_device)
 }
 
 /**
- * udev_device_get_devnum:
+ * udev_device_get_usec_since_initialized:
  * @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.
+ * Return the number of microseconds passed since udev set up the
+ * device for the first time.
  *
- * Returns: the kernel event sequence number, or 0 if there is no sequence number available.
+ * 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.
  **/
-unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
+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;
-       return udev_device->seqnum;
+       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)
+{
+       char num[32];
+
+       udev_device->usec_initialized = usec_initialized;
+       snprintf(num, sizeof(num), "%llu", usec_initialized);
+       udev_device_add_property(udev_device, "USEC_INITIALIZED", num);
 }
 
 /**
@@ -961,12 +1336,12 @@ unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
  * @udev_device: udev device
  * @sysattr: attribute name
  *
- * The retrieved value is cached in the device. Repeated reads will return the same
+ * 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.
  **/
-const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
+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];
@@ -982,43 +1357,50 @@ const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const
                return NULL;
 
        /* look for possibly already cached result */
-       udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_device->sysattr_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);
-               }
+       list_entry = udev_list_get_entry(&udev_device->sysattr_value_list);
+       list_entry = udev_list_entry_get_by_name(list_entry, sysattr);
+       if (list_entry != NULL) {
+               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_list, sysattr, NULL, 0, 0);
+               udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, NULL);
                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)
+               struct udev_device *dev;
+
+               /*
+                * Some core links return only the last element of the target path,
+                * these are just values, the paths should not be exposed.
+                */
+               if (strcmp(sysattr, "driver") == 0 ||
+                   strcmp(sysattr, "subsystem") == 0 ||
+                   strcmp(sysattr, "module") == 0) {
+                       if (util_get_sys_core_link_value(udev_device->udev, sysattr,
+                                                        udev_device->syspath, value, sizeof(value)) < 0)
+                               return NULL;
+                       dbg(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, value);
+                       list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, value);
+                       val = udev_list_entry_get_value(list_entry);
                        goto out;
+               }
 
-               len = readlink(path, target, sizeof(target));
-               if (len > 0) {
-                       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_list, sysattr, pos, 0, 0);
-                               val = udev_list_entry_get_value(list_entry);
-                       }
+               /* resolve link to a device and return its syspath */
+               util_strscpyl(path, sizeof(path), udev_device->syspath, "/", sysattr, NULL);
+               dev = udev_device_new_from_syspath(udev_device->udev, path);
+               if (dev != NULL) {
+                       list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr,
+                                                        udev_device_get_syspath(dev));
+                       val = udev_list_entry_get_value(list_entry);
+                       udev_device_unref(dev);
                }
+
                goto out;
        }
 
@@ -1031,7 +1413,7 @@ const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const
                goto out;
 
        /* read attribute value */
-       fd = open(path, O_RDONLY);
+       fd = open(path, O_RDONLY|O_CLOEXEC);
        if (fd < 0) {
                dbg(udev_device->udev, "attribute '%s' can not be opened\n", path);
                goto out;
@@ -1047,12 +1429,77 @@ const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const
        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_list, sysattr, value, 0, 0);
+       list_entry = udev_list_entry_add(&udev_device->sysattr_value_list, sysattr, value);
        val = udev_list_entry_get_value(list_entry);
 out:
        return val;
 }
 
+static int udev_device_sysattr_list_read(struct udev_device *udev_device)
+{
+       struct dirent *dent;
+       DIR *dir;
+       int num = 0;
+
+       if (udev_device == NULL)
+               return -1;
+       if (udev_device->sysattr_list_read)
+               return 0;
+
+       dir = opendir(udev_device_get_syspath(udev_device));
+       if (!dir) {
+               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->sysattr_list, dent->d_name, NULL);
+               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;
@@ -1091,98 +1538,136 @@ int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath
        return 0;
 }
 
-int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem)
-{
-       free(udev_device->subsystem);
-       udev_device->subsystem = strdup(subsystem);
-       if (udev_device->subsystem == NULL)
-               return -ENOMEM;
-       udev_device->subsystem_set = 1;
-       udev_device_add_property(udev_device, "SUBSYSTEM", udev_device->subsystem);
-       return 0;
-}
-
-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 = 1;
-       udev_device_add_property(udev_device, "DEVTYPE", udev_device->devtype);
-       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 (devnode == NULL)
-               return 0;
        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 udev_device_add_devlink(struct udev_device *udev_device, const char *devlink, int unique)
 {
-       udev_device->devlinks_uptodate = 0;
-       if (udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, 1, 0) == NULL)
+       struct udev_list_entry *list_entry;
+
+       udev_device->devlinks_uptodate = false;
+       list_entry = udev_list_entry_add(&udev_device->devlinks_list, devlink, NULL);
+       if (list_entry == NULL)
                return -ENOMEM;
+       if (unique)
+               udev_list_entry_set_num(list_entry, true);
        return 0;
 }
 
-struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
+const char *udev_device_get_id_filename(struct udev_device *udev_device)
 {
-       udev_device->envp_uptodate = 0;
-       if (value == NULL) {
-               struct udev_list_entry *list_entry;
+       if (udev_device->id_filename == NULL) {
+               if (udev_device_get_subsystem(udev_device) == NULL)
+                       return NULL;
 
-               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;
+               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_list_entry_add(udev_device->udev, &udev_device->properties_list, key, value, 1, 0);
+       return udev_device->id_filename;
 }
 
-struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
+/**
+ * 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)
 {
-       char name[UTIL_PATH_SIZE];
-       char *val;
+       if (!udev_device->info_loaded)
+               udev_device_read_db(udev_device, NULL);
+       return udev_device->is_initialized;
+}
 
-       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);
+void udev_device_set_is_initialized(struct udev_device *udev_device)
+{
+       udev_device->is_initialized = true;
+}
+
+int udev_device_add_tag(struct udev_device *udev_device, const char *tag)
+{
+       if (strchr(tag, ':') != NULL || strchr(tag, ' ') != NULL)
+               return -EINVAL;
+       udev_device->tags_uptodate = false;
+       if (udev_list_entry_add(&udev_device->tags_list, tag, NULL) != NULL)
+               return 0;
+       return -ENOMEM;
+}
+
+void udev_device_cleanup_tags_list(struct udev_device *udev_device)
+{
+       udev_device->tags_uptodate = false;
+       udev_list_cleanup(&udev_device->tags_list);
 }
 
 /**
- * udev_device_get_property_value:
+ * udev_device_get_tags_list_entry:
  * @udev_device: udev device
- * @key: property name
  *
- * Returns: the value of a device property, or #NULL if there is no such property.
+ * 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
  **/
-const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key)
+UDEV_EXPORT struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device)
 {
-       struct udev_list_entry *list_entry;
-
        if (udev_device == NULL)
                return NULL;
-       if (key == NULL)
-               return NULL;
+       if (!udev_device->info_loaded)
+               udev_device_read_db(udev_device, NULL);
+       return udev_list_get_entry(&udev_device->tags_list);
+}
 
-       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);
+UDEV_EXPORT int udev_device_has_tag(struct udev_device *udev_device, const char *tag)
+{
+       struct udev_list_entry *list_entry;
+
+       if (udev_device == NULL)
+               return false;
+       if (!udev_device->info_loaded)
+               udev_device_read_db(udev_device, NULL);
+       list_entry = udev_device_get_tags_list_entry(udev_device);
+       if (udev_list_entry_get_by_name(list_entry, tag) != NULL)
+               return true;
+       return false;
 }
 
 #define ENVP_SIZE                      128
@@ -1211,21 +1696,29 @@ static int update_envp_monitor_buf(struct udev_device *udev_device)
        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, udev_list_entry_get_name(list_entry), "=",
-                                 udev_list_entry_get_value(list_entry), NULL);
+               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 = 1;
+       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;
@@ -1258,107 +1751,10 @@ int udev_device_set_action(struct udev_device *udev_device, const char *action)
        return 0;
 }
 
-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 = 1;
-       udev_device_add_property(udev_device, "DRIVER", udev_device->driver);
-       return 0;
-}
-
-const char *udev_device_get_devpath_old(struct udev_device *udev_device)
-{
-       return udev_device->devpath_old;
-}
-
-int udev_device_set_devpath_old(struct udev_device *udev_device, const char *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);
-       return 0;
-}
-
-const char *udev_device_get_knodename(struct udev_device *udev_device)
-{
-       return udev_device->knodename;
-}
-
-int udev_device_set_knodename(struct udev_device *udev_device, const char *knodename)
-{
-       udev_device->knodename = strdup(knodename);
-       if (udev_device->knodename == NULL)
-               return -ENOMEM;
-       return 0;
-}
-
-int udev_device_get_timeout(struct udev_device *udev_device)
-{
-       return udev_device->timeout;
-}
-
-int udev_device_set_timeout(struct udev_device *udev_device, int timeout)
-{
-       udev_device->timeout = timeout;
-       return 0;
-}
-int udev_device_get_event_timeout(struct udev_device *udev_device)
-{
-       if (!udev_device->info_loaded)
-               device_load_info(udev_device);
-       return udev_device->event_timeout;
-}
-
-int udev_device_set_event_timeout(struct udev_device *udev_device, int event_timeout)
-{
-       udev_device->event_timeout = event_timeout;
-       return 0;
-}
-
-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_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_num_fake_partitions(struct udev_device *udev_device)
-{
-       if (!udev_device->info_loaded)
-               device_load_info(udev_device);
-       return udev_device->num_fake_partitions;
-}
-
-int udev_device_set_num_fake_partitions(struct udev_device *udev_device, int num)
-{
-       udev_device->num_fake_partitions = num;
-       return 0;
-}
-
 int udev_device_get_devlink_priority(struct udev_device *udev_device)
 {
        if (!udev_device->info_loaded)
-               device_load_info(udev_device);
+               udev_device_read_db(udev_device, NULL);
        return udev_device->devlink_priority;
 }
 
@@ -1368,28 +1764,25 @@ int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio)
        return 0;
 }
 
-int udev_device_get_ignore_remove(struct udev_device *udev_device)
+int udev_device_get_watch_handle(struct udev_device *udev_device)
 {
        if (!udev_device->info_loaded)
-               device_load_info(udev_device);
-       return udev_device->ignore_remove;
+               udev_device_read_db(udev_device, NULL);
+       return udev_device->watch_handle;
 }
 
-int udev_device_set_ignore_remove(struct udev_device *udev_device, int ignore)
+int udev_device_set_watch_handle(struct udev_device *udev_device, int handle)
 {
-       udev_device->ignore_remove = ignore;
+       udev_device->watch_handle = handle;
        return 0;
 }
 
-int udev_device_get_watch_handle(struct udev_device *udev_device)
+bool udev_device_get_db_persist(struct udev_device *udev_device)
 {
-       if (!udev_device->info_loaded)
-               device_load_info(udev_device);
-       return udev_device->watch_handle;
+       return udev_device->db_persist;
 }
 
-int udev_device_set_watch_handle(struct udev_device *udev_device, int handle)
+void udev_device_set_db_persist(struct udev_device *udev_device)
 {
-       udev_device->watch_handle = handle;
-       return 0;
+       udev_device->db_persist = true;
 }