[systemd-devel] [RFC][PATCH 1/2] libsystemd: add sd-device library

Tom Gundersen teg at jklm.no
Wed Apr 1 16:10:38 PDT 2015


After discussing this with Kay, I went ahead and pushed this. Feedback
still welcome of course.

Cheers,

Tom

On Wed, Apr 1, 2015 at 3:00 PM, Tom Gundersen <teg at jklm.no> wrote:
> This provides equivalent functionality to libudev-device, but in the
> systemd style. The public API only caters to creating sd_device objects
> from for devices that already exist in /sys, there is no support for
> listening for monitoring uevents or creating devices received over
> the udev netlink protocol.
>
> The private API contains the necessary functionality to make sd-device
> a drop-in replacement for libudev-device, but which we will not export
> publicly.
> ---
>
> Hi guys,
>
> This is another step on the way of ripping out the bits of libudev that will
> still be useful once the udev netlink transport has been replaced by kdbus.
>
> Feedback welcome.
>
> Cheers,
>
> Tom
>
>  Makefile.am                                |    9 +-
>  src/libsystemd/sd-device/device-internal.h |  125 ++
>  src/libsystemd/sd-device/device-private.c  | 1101 +++++++++++++++++
>  src/libsystemd/sd-device/device-private.h  |   63 +
>  src/libsystemd/sd-device/device-util.h     |   48 +
>  src/libsystemd/sd-device/sd-device.c       | 1812 ++++++++++++++++++++++++++++
>  src/systemd/sd-device.h                    |   77 ++
>  7 files changed, 3234 insertions(+), 1 deletion(-)
>  create mode 100644 src/libsystemd/sd-device/device-internal.h
>  create mode 100644 src/libsystemd/sd-device/device-private.c
>  create mode 100644 src/libsystemd/sd-device/device-private.h
>  create mode 100644 src/libsystemd/sd-device/device-util.h
>  create mode 100644 src/libsystemd/sd-device/sd-device.c
>  create mode 100644 src/systemd/sd-device.h
>
> diff --git a/Makefile.am b/Makefile.am
> index 93fdbc2..9509247 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -231,6 +231,7 @@ AM_CPPFLAGS = \
>         -I $(top_srcdir)/src/libsystemd/sd-rtnl \
>         -I $(top_srcdir)/src/libsystemd/sd-network \
>         -I $(top_srcdir)/src/libsystemd/sd-hwdb \
> +       -I $(top_srcdir)/src/libsystemd/sd-device \
>         -I $(top_srcdir)/src/libsystemd-network \
>         -I $(top_srcdir)/src/libsystemd-terminal \
>         $(OUR_CPPFLAGS)
> @@ -2918,6 +2919,7 @@ libsystemd_internal_la_SOURCES = \
>         src/systemd/sd-path.h \
>         src/systemd/sd-network.h \
>         src/systemd/sd-hwdb.h \
> +       src/systemd/sd-device.h \
>         src/libsystemd/sd-bus/sd-bus.c \
>         src/libsystemd/sd-bus/bus-control.c \
>         src/libsystemd/sd-bus/bus-control.h \
> @@ -2981,7 +2983,12 @@ libsystemd_internal_la_SOURCES = \
>         src/libsystemd/sd-network/network-util.c \
>         src/libsystemd/sd-hwdb/sd-hwdb.c \
>         src/libsystemd/sd-hwdb/hwdb-util.h \
> -       src/libsystemd/sd-hwdb/hwdb-internal.h
> +       src/libsystemd/sd-hwdb/hwdb-intenal.h \
> +       src/libsystemd/sd-device/device-internal.h \
> +       src/libsystemd/sd-device/device-util.h \
> +       src/libsystemd/sd-device/sd-device.c \
> +       src/libsystemd/sd-device/device-private.c \
> +       src/libsystemd/sd-device/device-private.h
>
>  nodist_libsystemd_internal_la_SOURCES = \
>         src/libsystemd/libsystemd.sym
> diff --git a/src/libsystemd/sd-device/device-internal.h b/src/libsystemd/sd-device/device-internal.h
> new file mode 100644
> index 0000000..59ec1a6
> --- /dev/null
> +++ b/src/libsystemd/sd-device/device-internal.h
> @@ -0,0 +1,125 @@
> +/***
> +  This file is part of systemd.
> +
> +  Copyright 2008-2012 Kay Sievers <kay at vrfy.org>
> +  Copyright 2014 Tom Gundersen <teg at jklm.no>
> +
> +  systemd is free software; you can redistribute it and/or modify it
> +  under the terms of the GNU Lesser General Public License as published by
> +  the Free Software Foundation; either version 2.1 of the License, or
> +  (at your option) any later version.
> +
> +  systemd is distributed in the hope that it will be useful, but
> +  WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> +  Lesser General Public License for more details.
> +
> +  You should have received a copy of the GNU Lesser General Public License
> +  along with systemd; If not, see <http://www.gnu.org/licenses/>.
> +***/
> +
> +#pragma once
> +
> +#include "hashmap.h"
> +#include "set.h"
> +
> +struct sd_device {
> +        uint64_t n_ref;
> +
> +        sd_device *parent;
> +        bool parent_set; /* no need to try to reload parent */
> +
> +        OrderedHashmap *properties;
> +        Iterator properties_iterator;
> +        uint64_t properties_generation; /* changes whenever the properties are changed */
> +        uint64_t properties_iterator_generation; /* generation when iteration was started */
> +
> +        /* the subset of the properties that should be written to the db*/
> +        OrderedHashmap *properties_db;
> +
> +        Hashmap *sysattr_values; /* cached sysattr values */
> +
> +        Set *sysattrs; /* names of sysattrs */
> +        Iterator sysattrs_iterator;
> +        bool sysattrs_read; /* don't try to re-read sysattrs once read */
> +
> +        Set *tags;
> +        Iterator tags_iterator;
> +        uint64_t tags_generation; /* changes whenever the tags are changed */
> +        uint64_t tags_iterator_generation; /* generation when iteration was started */
> +        bool property_tags_outdated; /* need to update TAGS= property */
> +
> +        Set *devlinks;
> +        Iterator devlinks_iterator;
> +        uint64_t devlinks_generation; /* changes whenever the devlinks are changed */
> +        uint64_t devlinks_iterator_generation; /* generation when iteration was started */
> +        bool property_devlinks_outdated; /* need to update DEVLINKS= property */
> +        int devlink_priority;
> +
> +        char **properties_strv; /* the properties hashmap as a strv */
> +        uint8_t *properties_nulstr; /* the same as a nulstr */
> +        size_t properties_nulstr_len;
> +        bool properties_buf_outdated; /* need to reread hashmap */
> +
> +        int watch_handle;
> +
> +        char *syspath;
> +        const char *devpath;
> +        const char *sysnum;
> +        char *sysname;
> +        bool sysname_set; /* don't reread sysname */
> +
> +        char *devtype;
> +        int ifindex;
> +        char *devname;
> +        dev_t devnum;
> +
> +        char *subsystem;
> +        bool subsystem_set; /* don't reread subsystem */
> +        char *driver;
> +        bool driver_set; /* don't reread driver */
> +
> +        char *id_filename;
> +
> +        bool is_initialized;
> +        uint64_t usec_initialized;
> +
> +        mode_t devmode;
> +        uid_t devuid;
> +        gid_t devgid;
> +
> +        bool uevent_loaded; /* don't reread uevent */
> +        bool db_loaded; /* don't reread db */
> +
> +        bool sealed; /* don't read more information from uevent/db */
> +        bool db_persist; /* don't clean up the db when switching from initrd to real root */
> +};
> +
> +typedef enum DeviceAction {
> +        DEVICE_ACTION_ADD,
> +        DEVICE_ACTION_REMOVE,
> +        DEVICE_ACTION_CHANGE,
> +        DEVICE_ACTION_MOVE,
> +        DEVICE_ACTION_ONLINE,
> +        DEVICE_ACTION_OFFLINE,
> +        _DEVICE_ACTION_MAX,
> +        _DEVICE_ACTION_INVALID = -1,
> +} DeviceAction;
> +
> +int device_new_aux(sd_device **ret);
> +int device_add_property_aux(sd_device *device, const char *key, const char *value, bool db);
> +int device_add_property_internal(sd_device *device, const char *key, const char *value);
> +int device_read_uevent_file(sd_device *device);
> +
> +int device_set_syspath(sd_device *device, const char *_syspath, bool verify);
> +int device_set_ifindex(sd_device *device, const char *ifindex);
> +int device_set_devmode(sd_device *device, const char *devmode);
> +int device_set_devname(sd_device *device, const char *_devname);
> +int device_set_devtype(sd_device *device, const char *_devtype);
> +int device_set_devnum(sd_device *device, const char *major, const char *minor);
> +int device_set_subsystem(sd_device *device, const char *_subsystem);
> +int device_set_driver(sd_device *device, const char *_driver);
> +int device_set_usec_initialized(sd_device *device, const char *initialized);
> +
> +DeviceAction device_action_from_string(const char *s) _pure_;
> +const char *device_action_to_string(DeviceAction a) _const_;
> diff --git a/src/libsystemd/sd-device/device-private.c b/src/libsystemd/sd-device/device-private.c
> new file mode 100644
> index 0000000..56f6dd2
> --- /dev/null
> +++ b/src/libsystemd/sd-device/device-private.c
> @@ -0,0 +1,1101 @@
> +/***
> +  This file is part of systemd.
> +
> +  Copyright 2008-2012 Kay Sievers <kay at vrfy.org>
> +  Copyright 2014 Tom Gundersen <teg at jklm.no>
> +
> +  systemd is free software; you can redistribute it and/or modify it
> +  under the terms of the GNU Lesser General Public License as published by
> +  the Free Software Foundation; either version 2.1 of the License, or
> +  (at your option) any later version.
> +
> +  systemd is distributed in the hope that it will be useful, but
> +  WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> +  Lesser General Public License for more details.
> +
> +  You should have received a copy of the GNU Lesser General Public License
> +  along with systemd; If not, see <http://www.gnu.org/licenses/>.
> +***/
> +
> +#include <ctype.h>
> +#include <sys/types.h>
> +#include <net/if.h>
> +
> +#include "util.h"
> +#include "macro.h"
> +#include "refcnt.h"
> +#include "path-util.h"
> +#include "strxcpyx.h"
> +#include "fileio.h"
> +#include "hashmap.h"
> +#include "set.h"
> +#include "strv.h"
> +#include "mkdir.h"
> +
> +#include "sd-device.h"
> +
> +#include "device-util.h"
> +#include "device-internal.h"
> +#include "device-private.h"
> +
> +int device_add_property(sd_device *device, const char *key, const char *value) {
> +        int r;
> +
> +        assert(device);
> +        assert(key);
> +
> +        r = device_add_property_aux(device, key, value, false);
> +        if (r < 0)
> +                return r;
> +
> +        if (key[0] != '.') {
> +                r = device_add_property_aux(device, key, value, true);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        return 0;
> +}
> +
> +static int device_add_property_internal_from_string(sd_device *device, const char *str) {
> +        _cleanup_free_ char *key = NULL;
> +        char *value;
> +
> +        assert(device);
> +        assert(str);
> +
> +        key = strdup(str);
> +        if (!key)
> +                return -ENOMEM;
> +
> +        value = strchr(key, '=');
> +        if (!value)
> +                return -EINVAL;
> +
> +        *value = '\0';
> +
> +        if (isempty(++value))
> +                value = NULL;
> +
> +        return device_add_property_internal(device, key, value);
> +}
> +
> +static int handle_db_line(sd_device *device, char key, const char *value) {
> +        char *path;
> +        int r;
> +
> +        assert(device);
> +        assert(value);
> +
> +        switch (key) {
> +        case 'S':
> +                path = strjoina("/dev/", value);
> +                r = device_add_devlink(device, path);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'L':
> +                r = safe_atoi(value, &device->devlink_priority);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'E':
> +                r = device_add_property_internal_from_string(device, value);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'G':
> +                r = device_add_tag(device, value);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'W':
> +                r = safe_atoi(value, &device->watch_handle);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'I':
> +                r = device_set_usec_initialized(device, value);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        default:
> +                log_debug("device db: unknown key '%c'", key);
> +        }
> +
> +        return 0;
> +}
> +
> +void device_set_devlink_priority(sd_device *device, int priority) {
> +        assert(device);
> +
> +        device->devlink_priority = priority;
> +}
> +
> +void device_set_is_initialized(sd_device *device) {
> +        assert(device);
> +
> +        device->is_initialized = true;
> +}
> +
> +int device_ensure_usec_initialized(sd_device *device, sd_device *device_old) {
> +        char num[DECIMAL_STR_MAX(usec_t)];
> +        usec_t usec_initialized;
> +        int r;
> +
> +        assert(device);
> +
> +        if (device_old && device_old->usec_initialized > 0)
> +                usec_initialized = device_old->usec_initialized;
> +        else
> +                usec_initialized = now(CLOCK_MONOTONIC);
> +
> +        r = snprintf(num, sizeof(num), USEC_FMT, usec_initialized);
> +        if (r < 0)
> +                return -errno;
> +
> +        r = device_set_usec_initialized(device, num);
> +        if (r < 0)
> +                return r;
> +
> +        return 0;
> +}
> +
> +static int device_read_db(sd_device *device) {
> +        _cleanup_free_ char *db = NULL;
> +        char *path;
> +        const char *id, *value;
> +        char key;
> +        size_t db_len;
> +        unsigned i;
> +        int r;
> +
> +        enum {
> +                PRE_KEY,
> +                KEY,
> +                PRE_VALUE,
> +                VALUE,
> +                INVALID_LINE,
> +        } state = PRE_KEY;
> +
> +        assert(device);
> +
> +        if (device->db_loaded || device->sealed)
> +                return 0;
> +
> +        r = device_get_id_filename(device, &id);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina("/run/udev/data/", id);
> +
> +        r = read_full_file(path, &db, &db_len);
> +        if (r < 0) {
> +                if (r == -ENOENT)
> +                        return 0;
> +                else {
> +                        log_debug("sd-device: failed to read db '%s': %s", path, strerror(-r));
> +                        return r;
> +                }
> +        }
> +
> +        /* devices with a database entry are initialized */
> +        device_set_is_initialized(device);
> +
> +        for (i = 0; i < db_len; i++) {
> +                switch (state) {
> +                case PRE_KEY:
> +                        if (!strchr(NEWLINE, db[i])) {
> +                                key = db[i];
> +
> +                                state = KEY;
> +                        }
> +
> +                        break;
> +                case KEY:
> +                        if (db[i] != ':') {
> +                                log_debug("sd-device: ignoring invalid db entry with key '%c'", key);
> +
> +                                state = INVALID_LINE;
> +                        } else {
> +                                db[i] = '\0';
> +
> +                                state = PRE_VALUE;
> +                        }
> +
> +                        break;
> +                case PRE_VALUE:
> +                        value = &db[i];
> +
> +                        state = VALUE;
> +
> +                        break;
> +                case INVALID_LINE:
> +                        if (strchr(NEWLINE, db[i]))
> +                                state = PRE_KEY;
> +
> +                        break;
> +                case VALUE:
> +                        if (strchr(NEWLINE, db[i])) {
> +                                db[i] = '\0';
> +                                r = handle_db_line(device, key, value);
> +                                if (r < 0)
> +                                        log_debug("sd-device: failed to handle db entry '%c:%s': %s", key, value, strerror(-r));
> +
> +                                state = PRE_KEY;
> +                        }
> +
> +                        break;
> +                default:
> +                        assert_not_reached("invalid state when parsing db");
> +                }
> +        }
> +
> +        device->db_loaded = true;
> +
> +        return 0;
> +}
> +
> +uint64_t device_get_properties_generation(sd_device *device) {
> +        assert(device);
> +
> +        return device->properties_generation;
> +}
> +
> +uint64_t device_get_tags_generation(sd_device *device) {
> +        assert(device);
> +
> +        return device->tags_generation;
> +}
> +
> +uint64_t device_get_devlinks_generation(sd_device *device) {
> +        assert(device);
> +
> +        return device->devlinks_generation;
> +}
> +
> +int device_get_devnode_mode(sd_device *device, mode_t *mode) {
> +        int r;
> +
> +        assert(device);
> +        assert(mode);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        *mode = device->devmode;
> +
> +        return 0;
> +}
> +
> +int device_get_devnode_uid(sd_device *device, uid_t *uid) {
> +        int r;
> +
> +        assert(device);
> +        assert(uid);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        *uid = device->devuid;
> +
> +        return 0;
> +}
> +
> +static int device_set_devuid(sd_device *device, const char *uid) {
> +        unsigned u;
> +        int r;
> +
> +        assert(device);
> +        assert(uid);
> +
> +        r = safe_atou(uid, &u);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_add_property_internal(device, "DEVUID", uid);
> +        if (r < 0)
> +                return r;
> +
> +        device->devuid = u;
> +
> +        return 0;
> +}
> +
> +int device_get_devnode_gid(sd_device *device, gid_t *gid) {
> +        int r;
> +
> +        assert(device);
> +        assert(gid);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        *gid = device->devgid;
> +
> +        return 0;
> +}
> +
> +static int device_set_devgid(sd_device *device, const char *gid) {
> +        unsigned g;
> +        int r;
> +
> +        assert(device);
> +        assert(gid);
> +
> +        r = safe_atou(gid, &g);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_add_property_internal(device, "DEVGID", gid);
> +        if (r < 0)
> +                return r;
> +
> +        device->devgid = g;
> +
> +        return 0;
> +}
> +
> +static int device_ammend(sd_device *device, const char *key, const char *value) {
> +        int r;
> +
> +        assert(device);
> +        assert(key);
> +        assert(value);
> +
> +        if (streq(key, "DEVPATH")) {
> +                char *path;
> +
> +                path = strjoina("/sys", value);
> +
> +                /* the caller must verify or trust this data (e.g., if it comes from the kernel) */
> +                r = device_set_syspath(device, path, false);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set syspath to '%s': %m", path);
> +        } else if (streq(key, "SUBSYSTEM")) {
> +                r = device_set_subsystem(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set subsystem to '%s': %m", value);
> +        } else if (streq(key, "DEVTYPE")) {
> +                r = device_set_devtype(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devtype to '%s': %m", value);
> +        } else if (streq(key, "DEVNAME")) {
> +                r = device_set_devname(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devname to '%s': %m", value);
> +        } else if (streq(key, "USEC_INITIALIZED")) {
> +                r = device_set_usec_initialized(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set usec-initialized to '%s': %m", value);
> +        } else if (streq(key, "DRIVER")) {
> +                r = device_set_driver(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set driver to '%s': %m", value);
> +        } else if (streq(key, "IFINDEX")) {
> +                r = device_set_ifindex(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set ifindex to '%s': %m", value);
> +        } else if (streq(key, "DEVMODE")) {
> +                r = device_set_devmode(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devmode to '%s': %m", value);
> +        } else if (streq(key, "DEVUID")) {
> +                r = device_set_devuid(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devuid to '%s': %m", value);
> +        } else if (streq(key, "DEVGID")) {
> +                r = device_set_devgid(device, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devgid to '%s': %m", value);
> +        } else if (streq(key, "DEVLINKS")) {
> +                char *devlinks, *next;
> +
> +                devlinks = strdupa(value);
> +
> +                while ((next = strchr(devlinks, ' '))) {
> +                        next[0] = '\0';
> +
> +                        r = device_add_devlink(device, devlinks);
> +                        if (r < 0)
> +                                return log_debug_errno(r, "sd-device: could not add devlink '%s': %m", devlinks);
> +
> +                        devlinks = next + 1;
> +                }
> +        } else if (streq(key, "TAGS")) {
> +                char *tags, *next;
> +
> +                tags = strdupa(value);
> +
> +                while ((next = strchr(tags, ':'))) {
> +                        next[0] = '\0';
> +
> +                        r = device_add_tag(device, tags);
> +                        if (r < 0)
> +                                return log_debug_errno(r, "sd-device: could not add tag '%s': %m", tags);
> +
> +                        tags = next + 1;
> +                }
> +        } else {
> +                r = device_add_property_internal(device, key, value);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not add property '%s=%s': %m", key, value);
> +        }
> +
> +        return 0;
> +}
> +
> +static const char* const device_action_table[_DEVICE_ACTION_MAX] = {
> +        [DEVICE_ACTION_ADD] = "add",
> +        [DEVICE_ACTION_REMOVE] = "remove",
> +        [DEVICE_ACTION_CHANGE] = "change",
> +        [DEVICE_ACTION_MOVE] = "move",
> +        [DEVICE_ACTION_ONLINE] = "online",
> +        [DEVICE_ACTION_OFFLINE] = "offline",
> +};
> +
> +DEFINE_STRING_TABLE_LOOKUP(device_action, DeviceAction);
> +
> +static int device_append(sd_device *device, char *key, const char **_major, const char **_minor, uint64_t *_seqnum,
> +                         DeviceAction *_action) {
> +        DeviceAction action = _DEVICE_ACTION_INVALID;
> +        uint64_t seqnum;
> +        const char *major = NULL, *minor = NULL;
> +        char *value;
> +        int r;
> +
> +        assert(device);
> +        assert(key);
> +        assert(_major);
> +        assert(_minor);
> +        assert(_seqnum);
> +        assert(_action);
> +
> +        value = strchr(key, '=');
> +        if (!value) {
> +                log_debug("sd-device: not a key-value pair: '%s'", key);
> +                return -EINVAL;
> +        }
> +
> +        *value = '\0';
> +
> +        value++;
> +
> +        if (streq(key, "MAJOR"))
> +                major = value;
> +        else if (streq(key, "MINOR"))
> +                minor = value;
> +        else {
> +                if (streq(key, "ACTION")) {
> +                        action = device_action_from_string(value);
> +                        if (action == _DEVICE_ACTION_INVALID)
> +                                return -EINVAL;
> +                } else if (streq(key, "SEQNUM")) {
> +                        r = safe_atou64(value, &seqnum);
> +                        if (r < 0)
> +                                return r;
> +                        else if (seqnum == 0)
> +                                 /* kernel only sends seqnum > 0 */
> +                                return -EINVAL;
> +                }
> +
> +                r = device_ammend(device, key, value);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        if (major != 0)
> +                *_major = major;
> +
> +        if (minor != 0)
> +                *_minor = minor;
> +
> +        if (action != _DEVICE_ACTION_INVALID)
> +                *_action = action;
> +
> +        if (seqnum > 0)
> +                *_seqnum = seqnum;
> +
> +        return 0;
> +}
> +
> +void device_seal(sd_device *device) {
> +        assert(device);
> +
> +        device->sealed = true;
> +}
> +
> +static int device_verify(sd_device *device, DeviceAction action, uint64_t seqnum) {
> +        assert(device);
> +
> +        if (!device->devpath || !device->subsystem || action == _DEVICE_ACTION_INVALID || seqnum == 0) {
> +                log_debug("sd-device: device created from strv lacks devpath, subsystem, action or seqnum");
> +                return -EINVAL;
> +        }
> +
> +        device->sealed = true;
> +
> +        return 0;
> +}
> +
> +int device_new_from_strv(sd_device **ret, char **strv) {
> +        _cleanup_device_unref_ sd_device *device = NULL;
> +        char **key;
> +        const char *major = NULL, *minor = NULL;
> +        DeviceAction action = _DEVICE_ACTION_INVALID;
> +        uint64_t seqnum;
> +        int r;
> +
> +        assert(ret);
> +        assert(strv);
> +
> +        r = device_new_aux(&device);
> +        if (r < 0)
> +                return r;
> +
> +        STRV_FOREACH(key, strv) {
> +                r = device_append(device, *key, &major, &minor, &seqnum, &action);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        if (major) {
> +                r = device_set_devnum(device, major, minor);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devnum %s:%s: %m", major, minor);
> +        }
> +
> +        r = device_verify(device, action, seqnum);
> +        if (r < 0)
> +                return r;
> +
> +        *ret = device;
> +        device = NULL;
> +
> +        return 0;
> +}
> +
> +int device_new_from_nulstr(sd_device **ret, uint8_t *nulstr, size_t len) {
> +        _cleanup_device_unref_ sd_device *device = NULL;
> +        const char *major = NULL, *minor = NULL;
> +        DeviceAction action = _DEVICE_ACTION_INVALID;
> +        uint64_t seqnum;
> +        unsigned i = 0;
> +        int r;
> +
> +        assert(ret);
> +        assert(nulstr);
> +        assert(len);
> +
> +        r = device_new_aux(&device);
> +        if (r < 0)
> +                return r;
> +
> +        while (i < len) {
> +                char *key;
> +                const char *end;
> +
> +                key = (char*)&nulstr[i];
> +                end = memchr(key, '\0', len - i);
> +                if (!end) {
> +                        log_debug("sd-device: failed to parse nulstr");
> +                        return -EINVAL;
> +                }
> +                i += end - key + 1;
> +
> +                r = device_append(device, key, &major, &minor, &seqnum, &action);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        if (major) {
> +                r = device_set_devnum(device, major, minor);
> +                if (r < 0)
> +                        return log_debug_errno(r, "sd-device: could not set devnum %s:%s: %m", major, minor);
> +        }
> +
> +        r = device_verify(device, action, seqnum);
> +        if (r < 0)
> +                return r;
> +
> +        *ret = device;
> +        device = NULL;
> +
> +        return 0;
> +}
> +
> +static int device_update_properties_bufs(sd_device *device) {
> +        const char *val, *prop;
> +        char **buf_strv = NULL;
> +        uint8_t *buf_nulstr = NULL;
> +        size_t allocated_nulstr = 0, allocated_strv = 0;
> +        size_t nulstr_len = 0, strv_size = 0;
> +
> +        assert(device);
> +
> +        FOREACH_DEVICE_PROPERTY(device, prop, val) {
> +                size_t len = 0;
> +
> +                len = strlen(prop) + 1 + strlen(val);
> +
> +                buf_nulstr = GREEDY_REALLOC0(buf_nulstr, allocated_nulstr, nulstr_len + len + 2);
> +                if (!buf_nulstr)
> +                        return -ENOMEM;
> +
> +                buf_strv = GREEDY_REALLOC0(buf_strv, allocated_strv, strv_size + 2);
> +                if (!buf_strv)
> +                        return -ENOMEM;
> +
> +                buf_strv[++ strv_size] = (char *)&buf_nulstr[nulstr_len];
> +                strscpyl((char *)buf_nulstr + nulstr_len, len + 1, prop, "=", val, NULL);
> +                nulstr_len += len + 1;
> +        }
> +
> +        free(device->properties_nulstr);
> +        free(device->properties_strv);
> +        device->properties_nulstr = buf_nulstr;
> +        device->properties_nulstr_len = nulstr_len;
> +        device->properties_strv = buf_strv;
> +
> +        device->properties_buf_outdated = false;
> +
> +        return 0;
> +}
> +
> +int device_get_properties_nulstr(sd_device *device, const uint8_t **nulstr, size_t *len) {
> +        int r;
> +
> +        assert(device);
> +        assert(nulstr);
> +        assert(len);
> +
> +        if (device->properties_buf_outdated) {
> +                r = device_update_properties_bufs(device);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        *nulstr = device->properties_nulstr;
> +        *len = device->properties_nulstr_len;
> +
> +        return 0;
> +}
> +
> +int device_get_properties_strv(sd_device *device, char ***strv) {
> +        int r;
> +
> +        assert(device);
> +        assert(strv);
> +
> +        r = device_update_properties_bufs(device);
> +        if (r < 0)
> +                return r;
> +
> +        *strv = device->properties_strv;
> +
> +        return 0;
> +}
> +
> +int device_get_devlink_priority(sd_device *device, int *priority) {
> +        int r;
> +
> +        assert(device);
> +        assert(priority);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        *priority = device->devlink_priority;
> +
> +        return 0;
> +}
> +
> +int device_get_watch_handle(sd_device *device, int *handle) {
> +        int r;
> +
> +        assert(device);
> +        assert(handle);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        *handle = device->watch_handle;
> +
> +        return 0;
> +}
> +
> +void device_set_watch_handle(sd_device *device, int handle) {
> +        assert(device);
> +
> +        device->watch_handle = handle;
> +}
> +
> +int device_rename(sd_device *device, const char *name) {
> +        _cleanup_free_ char *dirname = NULL;
> +        char *new_syspath;
> +        const char *interface;
> +        int r;
> +
> +        assert(device);
> +        assert(name);
> +
> +        dirname = dirname_malloc(device->syspath);
> +        if (!dirname)
> +                return -ENOMEM;
> +
> +        new_syspath = strjoina(dirname, "/", name);
> +
> +        /* the user must trust that the new name is correct */
> +        r = device_set_syspath(device, new_syspath, false);
> +        if (r < 0)
> +                return r;
> +
> +        r = sd_device_get_property_value(device, "INTERFACE", &interface);
> +        if (r >= 0) {
> +                r = device_add_property_internal(device, "INTERFACE", name);
> +                if (r < 0)
> +                        return r;
> +
> +                /* like DEVPATH_OLD, INTERFACE_OLD is not saved to the db, but only stays around for the current event */
> +                r = device_add_property_internal(device, "INTERFACE_OLD", interface);
> +                if (r < 0)
> +                        return r;
> +        } else if (r != -ENOENT)
> +                return r;
> +
> +        return 0;
> +}
> +
> +int device_shallow_clone(sd_device *old_device, sd_device **new_device) {
> +        _cleanup_device_unref_ sd_device *ret = NULL;
> +        int r;
> +
> +        assert(old_device);
> +        assert(new_device);
> +
> +        r = device_new_aux(&ret);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_set_syspath(ret, old_device->syspath, false);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_set_subsystem(ret, old_device->subsystem);
> +        if (r < 0)
> +                return r;
> +
> +        ret->devnum = old_device->devnum;
> +
> +        *new_device = ret;
> +        ret = NULL;
> +
> +        return 0;
> +}
> +
> +int device_clone_with_db(sd_device *old_device, sd_device **new_device) {
> +        _cleanup_device_unref_ sd_device *ret = NULL;
> +        int r;
> +
> +        assert(old_device);
> +        assert(new_device);
> +
> +        r = device_shallow_clone(old_device, &ret);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_read_db(ret);
> +        if (r < 0)
> +                return r;
> +
> +        ret->sealed = true;
> +
> +        *new_device = ret;
> +        ret = NULL;
> +
> +        return 0;
> +}
> +
> +int device_new_from_synthetic_event(sd_device **new_device, const char *syspath, const char *action) {
> +        _cleanup_device_unref_ sd_device *ret = NULL;
> +        int r;
> +
> +        assert(new_device);
> +        assert(syspath);
> +        assert(action);
> +
> +        r = sd_device_new_from_syspath(&ret, syspath);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_read_uevent_file(ret);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_add_property_internal(ret, "ACTION", action);
> +        if (r < 0)
> +                return r;
> +
> +        *new_device = ret;
> +        ret = NULL;
> +
> +        return 0;
> +}
> +
> +int device_copy_properties(sd_device *device_dst, sd_device *device_src) {
> +        const char *property, *value;
> +        int r;
> +
> +        assert(device_dst);
> +        assert(device_src);
> +
> +        FOREACH_DEVICE_PROPERTY(device_src, property, value) {
> +                r = device_add_property(device_dst, property, value);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        return r;
> +}
> +
> +void device_cleanup_tags(sd_device *device) {
> +        assert(device);
> +
> +        set_free_free(device->tags);
> +        device->tags = NULL;
> +        device->property_tags_outdated = true;
> +        device->tags_generation ++;
> +}
> +
> +void device_cleanup_devlinks(sd_device *device) {
> +        assert(device);
> +
> +        set_free_free(device->devlinks);
> +        device->devlinks = NULL;
> +        device->property_devlinks_outdated = true;
> +        device->devlinks_generation ++;
> +}
> +
> +void device_remove_tag(sd_device *device, const char *tag) {
> +        assert(device);
> +        assert(tag);
> +
> +        free(set_remove(device->tags, tag));
> +        device->property_tags_outdated = true;
> +        device->tags_generation ++;
> +}
> +
> +static int device_tag(sd_device *device, const char *tag, bool add) {
> +        const char *id;
> +        char *path;
> +        int r;
> +
> +        assert(device);
> +        assert(tag);
> +
> +        r = device_get_id_filename(device, &id);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina("/run/udev/tags/", tag, "/", id);
> +
> +        if (add) {
> +                r = touch_file(path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, 0444);
> +                if (r < 0)
> +                        return r;
> +        } else {
> +                r = unlink(path);
> +                if (r < 0 && errno != ENOENT)
> +                        return -errno;
> +        }
> +
> +        return 0;
> +}
> +
> +int device_tag_index(sd_device *device, sd_device *device_old, bool add) {
> +        const char *tag;
> +        int r = 0, k;
> +
> +        if (add && device_old) {
> +                /* delete possible left-over tags */
> +                FOREACH_DEVICE_TAG(device_old, tag) {
> +                        if (!sd_device_has_tag(device, tag)) {
> +                                k = device_tag(device_old, tag, false);
> +                                if (r >= 0 && k < 0)
> +                                        r = k;
> +                        }
> +                }
> +        }
> +
> +        FOREACH_DEVICE_TAG(device, tag) {
> +                k = device_tag(device, tag, add);
> +                if (r >= 0 && k < 0)
> +                        r = k;
> +        }
> +
> +        return r;
> +}
> +
> +static bool device_has_info(sd_device *device) {
> +        assert(device);
> +
> +        if (!set_isempty(device->devlinks))
> +                return true;
> +
> +        if (device->devlink_priority != 0)
> +                return true;
> +
> +        if (!ordered_hashmap_isempty(device->properties_db))
> +                return true;
> +
> +        if (!set_isempty(device->tags))
> +                return true;
> +
> +        if (device->watch_handle >= 0)
> +                return true;
> +
> +        return false;
> +}
> +
> +void device_set_db_persist(sd_device *device) {
> +        assert(device);
> +
> +        device->db_persist = true;
> +}
> +
> +int device_update_db(sd_device *device) {
> +        const char *id;
> +        char *path;
> +        _cleanup_fclose_ FILE *f = NULL;
> +        _cleanup_free_ char *path_tmp = NULL;
> +        bool has_info;
> +        int r;
> +
> +        assert(device);
> +
> +        has_info = device_has_info(device);
> +
> +        r = device_get_id_filename(device, &id);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina("/run/udev/data/", id);
> +
> +        /* do not store anything for otherwise empty devices */
> +        if (!has_info && major(device->devnum) == 0 && device->ifindex == 0) {
> +                r = unlink(path);
> +                if (r < 0 && errno != ENOENT)
> +                        return -errno;
> +
> +                return 0;
> +        }
> +
> +        /* write a database file */
> +        r = mkdir_parents(path, 0755);
> +        if (r < 0)
> +                return r;
> +
> +        r = fopen_temporary(path, &f, &path_tmp);
> +        if (r < 0)
> +                return r;
> +
> +        /*
> +         * set 'sticky' bit to indicate that we should not clean the
> +         * database when we transition from initramfs to the real root
> +         */
> +        if (device->db_persist) {
> +                r = fchmod(fileno(f), 01644);
> +                if (r < 0) {
> +                        r = -errno;
> +                        goto fail;
> +                }
> +        } else {
> +                r = fchmod(fileno(f), 0644);
> +                if (r < 0) {
> +                        r = -errno;
> +                        goto fail;
> +                }
> +        }
> +
> +        if (has_info) {
> +                const char *property, *value, *tag;
> +                Iterator i;
> +
> +                if (major(device->devnum) > 0) {
> +                        const char *devlink;
> +
> +                        FOREACH_DEVICE_DEVLINK(device, devlink)
> +                                fprintf(f, "S:%s\n", devlink + strlen("/dev/"));
> +
> +                        if (device->devlink_priority != 0)
> +                                fprintf(f, "L:%i\n", device->devlink_priority);
> +
> +                        if (device->watch_handle >= 0)
> +                                fprintf(f, "W:%i\n", device->watch_handle);
> +                }
> +
> +                if (device->usec_initialized > 0)
> +                        fprintf(f, "I:"USEC_FMT"\n", device->usec_initialized);
> +
> +                ORDERED_HASHMAP_FOREACH_KEY(value, property, device->properties_db, i)
> +                        fprintf(f, "E:%s=%s\n", property, value);
> +
> +                FOREACH_DEVICE_TAG(device, tag)
> +                        fprintf(f, "G:%s\n", tag);
> +        }
> +
> +        r = fflush_and_check(f);
> +        if (r < 0)
> +                goto fail;
> +
> +        r = rename(path_tmp, path);
> +        if (r < 0) {
> +                r = -errno;
> +                goto fail;
> +        }
> +
> +        log_debug("created %s file '%s' for '%s'", has_info ? "db" : "empty",
> +                  path, device->devpath);
> +
> +        return 0;
> +
> +fail:
> +        log_error_errno(r, "failed to create %s file '%s' for '%s'", has_info ? "db" : "empty",
> +                        path, device->devpath);
> +        unlink(path);
> +        unlink(path_tmp);
> +
> +        return r;
> +}
> +
> +int device_delete_db(sd_device *device) {
> +        const char *id;
> +        char *path;
> +        int r;
> +
> +        assert(device);
> +
> +        r = device_get_id_filename(device, &id);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina("/run/udev/data/", id);
> +
> +        r = unlink(path);
> +        if (r < 0 && errno != ENOENT)
> +                return -errno;
> +
> +        return 0;
> +}
> diff --git a/src/libsystemd/sd-device/device-private.h b/src/libsystemd/sd-device/device-private.h
> new file mode 100644
> index 0000000..7c6219c
> --- /dev/null
> +++ b/src/libsystemd/sd-device/device-private.h
> @@ -0,0 +1,63 @@
> +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
> +
> +#pragma once
> +
> +/***
> +  This file is part of systemd.
> +
> +  Copyright 2014 Tom Gundersen <teg at jklm.no>
> +
> +  systemd is free software; you can redistribute it and/or modify it
> +  under the terms of the GNU Lesser General Public License as published by
> +  the Free Software Foundation; either version 2.1 of the License, or
> +  (at your option) any later version.
> +
> +  systemd is distributed in the hope that it will be useful, but
> +  WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> +  Lesser General Public License for more details.
> +
> +  You should have received a copy of the GNU Lesser General Public License
> +  along with systemd; If not, see <http://www.gnu.org/licenses/>.
> +***/
> +
> +int device_new_from_nulstr(sd_device **ret, uint8_t *nulstr, size_t len);
> +int device_new_from_strv(sd_device **ret, char **strv);
> +
> +int device_get_id_filename(sd_device *device, const char **ret);
> +
> +int device_get_devlink_priority(sd_device *device, int *priority);
> +int device_get_watch_handle(sd_device *device, int *handle);
> +int device_get_devnode_mode(sd_device *device, mode_t *mode);
> +int device_get_devnode_uid(sd_device *device, uid_t *uid);
> +int device_get_devnode_gid(sd_device *device, gid_t *gid);
> +
> +void device_seal(sd_device *device);
> +void device_set_is_initialized(sd_device *device);
> +void device_set_watch_handle(sd_device *device, int fd);
> +void device_set_db_persist(sd_device *device);
> +void device_set_devlink_priority(sd_device *device, int priority);
> +int device_ensure_usec_initialized(sd_device *devcie, sd_device *device_old);
> +int device_add_devlink(sd_device *device, const char *devlink);
> +int device_add_property(sd_device *device, const char *property, const char *value);
> +int device_add_tag(sd_device *device, const char *tag);
> +void device_remove_tag(sd_device *device, const char *tag);
> +void device_cleanup_tags(sd_device *device);
> +void device_cleanup_devlinks(sd_device *device);
> +
> +uint64_t device_get_properties_generation(sd_device *device);
> +uint64_t device_get_tags_generation(sd_device *device);
> +uint64_t device_get_devlinks_generation(sd_device *device);
> +
> +int device_get_properties_nulstr(sd_device *device, const uint8_t **nulstr, size_t *len);
> +int device_get_properties_strv(sd_device *device, char ***strv);
> +
> +int device_rename(sd_device *device, const char *name);
> +int device_shallow_clone(sd_device *old_device, sd_device **new_device);
> +int device_clone_with_db(sd_device *old_device, sd_device **new_device);
> +int device_copy_properties(sd_device *device_dst, sd_device *device_src);
> +int device_new_from_synthetic_event(sd_device **new_device, const char *syspath, const char *action);
> +
> +int device_tag_index(sd_device *dev, sd_device *dev_old, bool add);
> +int device_update_db(sd_device *device);
> +int device_delete_db(sd_device *device);
> diff --git a/src/libsystemd/sd-device/device-util.h b/src/libsystemd/sd-device/device-util.h
> new file mode 100644
> index 0000000..bfbb328
> --- /dev/null
> +++ b/src/libsystemd/sd-device/device-util.h
> @@ -0,0 +1,48 @@
> +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
> +
> +#pragma once
> +
> +/***
> +  This file is part of systemd.
> +
> +  Copyright 2014 Tom Gundersen <teg at jklm.no>
> +
> +  systemd is free software; you can redistribute it and/or modify it
> +  under the terms of the GNU Lesser General Public License as published by
> +  the Free Software Foundation; either version 2.1 of the License, or
> +  (at your option) any later version.
> +
> +  systemd is distributed in the hope that it will be useful, but
> +  WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> +  Lesser General Public License for more details.
> +
> +  You should have received a copy of the GNU Lesser General Public License
> +  along with systemd; If not, see <http://www.gnu.org/licenses/>.
> +***/
> +
> +#include "util.h"
> +
> +DEFINE_TRIVIAL_CLEANUP_FUNC(sd_device*, sd_device_unref);
> +
> +#define _cleanup_device_unref_ _cleanup_(sd_device_unrefp)
> +
> +#define FOREACH_DEVICE_PROPERTY(device, key, value)                \
> +        for (key = sd_device_get_property_first(device, &(value)); \
> +             key;                                                  \
> +             key = sd_device_get_property_next(device, &(value)))
> +
> +#define FOREACH_DEVICE_TAG(device, tag)             \
> +        for (tag = sd_device_get_tag_first(device); \
> +             tag;                                   \
> +             tag = sd_device_get_tag_next(device))
> +
> +#define FOREACH_DEVICE_SYSATTR(device, attr)             \
> +        for (attr = sd_device_get_sysattr_first(device); \
> +             attr;                                       \
> +             attr = sd_device_get_sysattr_next(device))
> +
> +#define FOREACH_DEVICE_DEVLINK(device, devlink)             \
> +        for (devlink = sd_device_get_devlink_first(device); \
> +             devlink;                                   \
> +             devlink = sd_device_get_devlink_next(device))
> diff --git a/src/libsystemd/sd-device/sd-device.c b/src/libsystemd/sd-device/sd-device.c
> new file mode 100644
> index 0000000..921adfd
> --- /dev/null
> +++ b/src/libsystemd/sd-device/sd-device.c
> @@ -0,0 +1,1812 @@
> +/***
> +  This file is part of systemd.
> +
> +  Copyright 2008-2012 Kay Sievers <kay at vrfy.org>
> +  Copyright 2014 Tom Gundersen <teg at jklm.no>
> +
> +  systemd is free software; you can redistribute it and/or modify it
> +  under the terms of the GNU Lesser General Public License as published by
> +  the Free Software Foundation; either version 2.1 of the License, or
> +  (at your option) any later version.
> +
> +  systemd is distributed in the hope that it will be useful, but
> +  WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> +  Lesser General Public License for more details.
> +
> +  You should have received a copy of the GNU Lesser General Public License
> +  along with systemd; If not, see <http://www.gnu.org/licenses/>.
> +***/
> +
> +#include <ctype.h>
> +#include <sys/types.h>
> +#include <net/if.h>
> +
> +#include "util.h"
> +#include "macro.h"
> +#include "path-util.h"
> +#include "strxcpyx.h"
> +#include "fileio.h"
> +#include "hashmap.h"
> +#include "set.h"
> +#include "strv.h"
> +
> +#include "sd-device.h"
> +
> +#include "device-util.h"
> +#include "device-private.h"
> +#include "device-internal.h"
> +
> +int device_new_aux(sd_device **ret) {
> +        _cleanup_device_unref_ sd_device *device = NULL;
> +
> +        assert(ret);
> +
> +        device = new0(sd_device, 1);
> +        if (!device)
> +                return -ENOMEM;
> +
> +        device->n_ref = 1;
> +        device->watch_handle = -1;
> +
> +        *ret = device;
> +        device = NULL;
> +
> +        return 0;
> +}
> +
> +_public_ sd_device *sd_device_ref(sd_device *device) {
> +        if (device)
> +                assert_se(++ device->n_ref >= 2);
> +
> +        return device;
> +}
> +
> +_public_ sd_device *sd_device_unref(sd_device *device) {
> +        if (device && -- device->n_ref == 0) {
> +                sd_device_unref(device->parent);
> +                free(device->syspath);
> +                free(device->sysname);
> +                free(device->devtype);
> +                free(device->devname);
> +                free(device->subsystem);
> +                free(device->driver);
> +                free(device->id_filename);
> +                free(device->properties_strv);
> +                free(device->properties_nulstr);
> +
> +                ordered_hashmap_free_free_free(device->properties);
> +                ordered_hashmap_free_free_free(device->properties_db);
> +                hashmap_free_free_free(device->sysattr_values);
> +                set_free_free(device->sysattrs);
> +                set_free_free(device->tags);
> +                set_free_free(device->devlinks);
> +
> +                free(device);
> +        }
> +
> +        return NULL;
> +}
> +
> +int device_add_property_aux(sd_device *device, const char *_key, const char *_value, bool db) {
> +        OrderedHashmap **properties;
> +
> +        assert(device);
> +        assert(_key);
> +
> +        if (db)
> +                properties = &device->properties_db;
> +        else
> +                properties = &device->properties;
> +
> +        if (_value) {
> +                _cleanup_free_ char *key = NULL, *value = NULL, *old_key = NULL, *old_value = NULL;
> +                int r;
> +
> +                r = ordered_hashmap_ensure_allocated(properties, &string_hash_ops);
> +                if (r < 0)
> +                        return r;
> +
> +                key = strdup(_key);
> +                if (!key)
> +                        return -ENOMEM;
> +
> +                value = strdup(_value);
> +                if (!value)
> +                        return -ENOMEM;
> +
> +                old_value = ordered_hashmap_get2(*properties, key, (void**) &old_key);
> +
> +                r = ordered_hashmap_replace(*properties, key, value);
> +                if (r < 0)
> +                        return r;
> +
> +                key = NULL;
> +                value = NULL;
> +        } else {
> +                _cleanup_free_ char *key = NULL;
> +                _cleanup_free_ char *value = NULL;
> +
> +                value = ordered_hashmap_remove2(*properties, _key, (void**) &key);
> +        }
> +
> +        if (!db) {
> +                device->properties_generation ++;
> +                device->properties_buf_outdated = true;
> +        }
> +
> +        return 0;
> +}
> +
> +int device_add_property_internal(sd_device *device, const char *key, const char *value) {
> +        return device_add_property_aux(device, key, value, false);
> +}
> +
> +int device_set_syspath(sd_device *device, const char *_syspath, bool verify) {
> +        _cleanup_free_ char *syspath = NULL;
> +        const char *devpath;
> +        int r;
> +
> +        assert(device);
> +        assert(_syspath);
> +
> +        /* must be a subdirectory of /sys */
> +        if (!path_startswith(_syspath, "/sys/")) {
> +                log_debug("sd-device: syspath '%s' is not a subdirectory of /sys", _syspath);
> +                return -EINVAL;
> +        }
> +
> +        if (verify) {
> +                r = readlink_and_canonicalize(_syspath, &syspath);
> +                if (r == -EINVAL) {
> +                        /* not a symlink */
> +                        syspath = canonicalize_file_name(_syspath);
> +                        if (!syspath) {
> +                                log_debug("sd-device: could not canonicalize '%s': %m", _syspath);
> +                                return -errno;
> +                        }
> +                /* ignore errors due to the link not being a symlink */
> +                } else if (r < 0 && r != -EINVAL) {
> +                        log_debug("sd-device: could not get target of '%s': %s", _syspath, strerror(-r));
> +                        return r;
> +                }
> +
> +                if (path_startswith(syspath,  "/sys/devices/")) {
> +                        char *path;
> +
> +                        /* all 'devices' require an 'uevent' file */
> +                        path = strjoina(syspath, "/uevent");
> +                        r = access(path, F_OK);
> +                        if (r < 0) {
> +                                log_debug("sd-device: %s does not have an uevent file: %m", syspath);
> +                                return -errno;
> +                        }
> +                } else {
> +                        /* everything else just just needs to be a directory */
> +                        if (!is_dir(syspath, false)) {
> +                                log_debug("sd-device: %s is not a directory", syspath);
> +                                return -EINVAL;
> +                        }
> +                }
> +        } else {
> +                syspath = strdup(_syspath);
> +                if (!syspath)
> +                        return -ENOMEM;
> +        }
> +
> +        devpath = syspath + strlen("/sys");
> +
> +        r = device_add_property_internal(device, "DEVPATH", devpath);
> +        if (r < 0)
> +                return r;
> +
> +        free(device->syspath);
> +        device->syspath = syspath;
> +        syspath = NULL;
> +
> +        device->devpath = devpath;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_new_from_syspath(sd_device **ret, const char *syspath) {
> +        _cleanup_device_unref_ sd_device *device = NULL;
> +        int r;
> +
> +        assert_return(ret, -EINVAL);
> +        assert_return(syspath, -EINVAL);
> +
> +        r = device_new_aux(&device);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_set_syspath(device, syspath, true);
> +        if (r < 0)
> +                return r;
> +
> +        *ret = device;
> +        device = NULL;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum) {
> +        char *syspath;
> +        char id[DECIMAL_STR_MAX(unsigned) * 2 + 1];
> +
> +        assert_return(ret, -EINVAL);
> +        assert_return(type == 'b' || type == 'c', -EINVAL);
> +
> +        /* use /sys/dev/{block,char}/<maj>:<min> link */
> +        snprintf(id, sizeof(id), "%u:%u", major(devnum), minor(devnum));
> +
> +        syspath = strjoina("/sys/dev/", (type == 'b' ? "block" : "char"), "/", id);
> +
> +        return sd_device_new_from_syspath(ret, syspath);
> +}
> +
> +_public_ int sd_device_new_from_subsystem_sysname(sd_device **ret, const char *subsystem, const char *sysname) {
> +        char *syspath;
> +
> +        assert_return(ret, -EINVAL);
> +        assert_return(subsystem, -EINVAL);
> +        assert_return(sysname, -EINVAL);
> +
> +        if (streq(subsystem, "subsystem")) {
> +                syspath = strjoina("/sys/subsystem/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +
> +                syspath = strjoina("/sys/bus/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +
> +                syspath = strjoina("/sys/class/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +        } else  if (streq(subsystem, "module")) {
> +                syspath = strjoina("/sys/module/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +        } else if (streq(subsystem, "drivers")) {
> +                char subsys[PATH_MAX];
> +                char *driver;
> +
> +                strscpy(subsys, sizeof(subsys), sysname);
> +                driver = strchr(subsys, ':');
> +                if (driver) {
> +                        driver[0] = '\0';
> +                        driver++;
> +
> +                        syspath = strjoina("/sys/subsystem/", subsys, "/drivers/", driver);
> +                        if (access(syspath, F_OK) >= 0)
> +                                return sd_device_new_from_syspath(ret, syspath);
> +
> +                        syspath = strjoina("/sys/bus/", subsys, "/drivers/", driver);
> +                        if (access(syspath, F_OK) >= 0)
> +                                return sd_device_new_from_syspath(ret, syspath);
> +                } else
> +                        return -EINVAL;
> +        } else {
> +                syspath = strjoina("/sys/subsystem/", subsystem, "/devices/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +
> +                syspath = strjoina("/sys/bus/", subsystem, "/devices/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +
> +                syspath = strjoina("/sys/class/", subsystem, "/", sysname);
> +                if (access(syspath, F_OK) >= 0)
> +                        return sd_device_new_from_syspath(ret, syspath);
> +        }
> +
> +        return -ENOENT;
> +}
> +
> +int device_set_devtype(sd_device *device, const char *_devtype) {
> +        _cleanup_free_ char *devtype = NULL;
> +        int r;
> +
> +        assert(device);
> +        assert(_devtype);
> +
> +        devtype = strdup(_devtype);
> +        if (!devtype)
> +                return -ENOMEM;
> +
> +        r = device_add_property_internal(device, "DEVTYPE", devtype);
> +        if (r < 0)
> +                return r;
> +
> +        free(device->devtype);
> +        device->devtype = devtype;
> +        devtype = NULL;
> +
> +        return 0;
> +}
> +
> +int device_set_ifindex(sd_device *device, const char *_ifindex) {
> +        int ifindex, r;
> +
> +        assert(device);
> +        assert(_ifindex);
> +
> +        r = safe_atoi(_ifindex, &ifindex);
> +        if (r < 0)
> +                return r;
> +
> +        if (ifindex <= 0)
> +                return -EINVAL;
> +
> +        r = device_add_property_internal(device, "IFINDEX", _ifindex);
> +        if (r < 0)
> +                return r;
> +
> +        device->ifindex = ifindex;
> +
> +        return 0;
> +}
> +
> +int device_set_devname(sd_device *device, const char *_devname) {
> +        _cleanup_free_ char *devname = NULL;
> +        int r;
> +
> +        assert(device);
> +        assert(_devname);
> +
> +        if (_devname[0] != '/') {
> +                r = asprintf(&devname, "/dev/%s", _devname);
> +                if (r < 0)
> +                        return -ENOMEM;
> +        } else {
> +                devname = strdup(_devname);
> +                if (!devname)
> +                        return -ENOMEM;
> +        }
> +
> +        r = device_add_property_internal(device, "DEVNAME", devname);
> +        if (r < 0)
> +                return r;
> +
> +        free(device->devname);
> +        device->devname = devname;
> +        devname = NULL;
> +
> +        return 0;
> +}
> +
> +int device_set_devmode(sd_device *device, const char *_devmode) {
> +        unsigned devmode;
> +        int r;
> +
> +        assert(device);
> +        assert(_devmode);
> +
> +        r = safe_atou(_devmode, &devmode);
> +        if (r < 0)
> +                return r;
> +
> +        if (devmode > 07777)
> +                return -EINVAL;
> +
> +        r = device_add_property_internal(device, "DEVMODE", _devmode);
> +        if (r < 0)
> +                return r;
> +
> +        device->devmode = devmode;
> +
> +        return 0;
> +}
> +
> +int device_set_devnum(sd_device *device, const char *major, const char *minor) {
> +        unsigned maj = 0, min = 0;
> +        int r;
> +
> +        assert(device);
> +        assert(major);
> +
> +        r = safe_atou(major, &maj);
> +        if (r < 0)
> +                return r;
> +        if (!maj)
> +                return 0;
> +
> +        if (minor) {
> +                r = safe_atou(minor, &min);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        r = device_add_property_internal(device, "MAJOR", major);
> +        if (r < 0)
> +                return r;
> +
> +        if (minor) {
> +                r = device_add_property_internal(device, "MINOR", minor);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        device->devnum = makedev(maj, min);
> +
> +        return 0;
> +}
> +
> +static int handle_uevent_line(sd_device *device, const char *key, const char *value, const char **major, const char **minor) {
> +        int r;
> +
> +        assert(device);
> +        assert(key);
> +        assert(value);
> +        assert(major);
> +        assert(minor);
> +
> +        if (streq(key, "DEVTYPE")) {
> +                r = device_set_devtype(device, value);
> +                if (r < 0)
> +                        return r;
> +        } else if (streq(key, "IFINDEX")) {
> +                r = device_set_ifindex(device, value);
> +                if (r < 0)
> +                        return r;
> +        } else if (streq(key, "DEVNAME")) {
> +                r = device_set_devname(device, value);
> +                if (r < 0)
> +                        return r;
> +        } else if (streq(key, "DEVMODE")) {
> +                r = device_set_devmode(device, value);
> +                if (r < 0)
> +                        return r;
> +        } else if (streq(key, "MAJOR"))
> +                *major = value;
> +        else if (streq(key, "MINOR"))
> +                *minor = value;
> +        else {
> +                r = device_add_property_internal(device, key, value);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        return 0;
> +}
> +
> +int device_read_uevent_file(sd_device *device) {
> +        _cleanup_free_ char *uevent = NULL;
> +        const char *syspath, *key, *value, *major = NULL, *minor = NULL;
> +        char *path;
> +        size_t uevent_len;
> +        unsigned i;
> +        int r;
> +
> +        enum {
> +                PRE_KEY,
> +                KEY,
> +                PRE_VALUE,
> +                VALUE,
> +                INVALID_LINE,
> +        } state = PRE_KEY;
> +
> +        assert(device);
> +
> +        if (device->uevent_loaded || device->sealed)
> +                return 0;
> +
> +        r = sd_device_get_syspath(device, &syspath);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina(syspath, "/uevent");
> +
> +        r = read_full_file(path, &uevent, &uevent_len);
> +        if (r < 0) {
> +                log_debug("sd-device: failed to read uevent file '%s': %s", path, strerror(-r));
> +                return r;
> +        }
> +
> +        for (i = 0; i < uevent_len; i++) {
> +                switch (state) {
> +                case PRE_KEY:
> +                        if (!strchr(NEWLINE, uevent[i])) {
> +                                key = &uevent[i];
> +
> +                                state = KEY;
> +                        }
> +
> +                        break;
> +                case KEY:
> +                        if (uevent[i] == '=') {
> +                                uevent[i] = '\0';
> +
> +                                state = PRE_VALUE;
> +                        } else if (strchr(NEWLINE, uevent[i])) {
> +                                uevent[i] = '\0';
> +                                log_debug("sd-device: ignoring invalid uevent line '%s'", key);
> +
> +                                state = PRE_KEY;
> +                        }
> +
> +                        break;
> +                case PRE_VALUE:
> +                        value = &uevent[i];
> +
> +                        state = VALUE;
> +
> +                        break;
> +                case VALUE:
> +                        if (strchr(NEWLINE, uevent[i])) {
> +                                uevent[i] = '\0';
> +
> +                                r = handle_uevent_line(device, key, value, &major, &minor);
> +                                if (r < 0)
> +                                        log_debug("sd-device: failed to handle uevent entry '%s=%s': %s", key, value, strerror(-r));
> +
> +                                state = PRE_KEY;
> +                        }
> +
> +                        break;
> +                default:
> +                        assert_not_reached("invalid state when parsing uevent file");
> +                }
> +        }
> +
> +        if (major) {
> +                r = device_set_devnum(device, major, minor);
> +                if (r < 0)
> +                        log_debug("sd-device: could not set 'MAJOR=%s' or 'MINOR=%s' from '%s': %s", major, minor, path, strerror(-r));
> +        }
> +
> +        device->uevent_loaded = true;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_ifindex(sd_device *device, int *ifindex) {
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(ifindex, -EINVAL);
> +
> +        r = device_read_uevent_file(device);
> +        if (r < 0)
> +                return r;
> +
> +        *ifindex = device->ifindex;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_new_from_device_id(sd_device **ret, const char *id) {
> +        int r;
> +
> +        assert_return(ret, -EINVAL);
> +        assert_return(id, -EINVAL);
> +
> +        switch (id[0]) {
> +        case 'b':
> +        case 'c':
> +        {
> +                char type;
> +                int maj, min;
> +
> +                r = sscanf(id, "%c%i:%i", &type, &maj, &min);
> +                if (r != 3)
> +                        return -EINVAL;
> +
> +                return sd_device_new_from_devnum(ret, type, makedev(maj, min));
> +        }
> +        case 'n':
> +        {
> +                _cleanup_device_unref_ sd_device *device = NULL;
> +                _cleanup_close_ int sk = -1;
> +                struct ifreq ifr = {};
> +                int ifindex;
> +
> +                r = safe_atoi(&id[1], &ifr.ifr_ifindex);
> +                if (r < 0)
> +                        return r;
> +                else if (ifr.ifr_ifindex <= 0)
> +                        return -EINVAL;
> +
> +                sk = socket(PF_INET, SOCK_DGRAM, 0);
> +                if (sk < 0)
> +                        return -errno;
> +
> +                r = ioctl(sk, SIOCGIFNAME, &ifr);
> +                if (r < 0)
> +                        return -errno;
> +
> +                r = sd_device_new_from_subsystem_sysname(&device, "net", ifr.ifr_name);
> +                if (r < 0)
> +                        return r;
> +
> +                r = sd_device_get_ifindex(device, &ifindex);
> +                if (r < 0)
> +                        return r;
> +
> +                /* this si racey, so we might end up with the wrong device */
> +                if (ifr.ifr_ifindex != ifindex)
> +                        return -ENODEV;
> +
> +                *ret = device;
> +                device = NULL;
> +
> +                return 0;
> +        }
> +        case '+':
> +        {
> +                char subsys[PATH_MAX];
> +                char *sysname;
> +
> +                (void)strscpy(subsys, sizeof(subsys), id + 1);
> +                sysname = strchr(subsys, ':');
> +                if (!sysname)
> +                        return -EINVAL;
> +
> +                sysname[0] = '\0';
> +                sysname ++;
> +
> +                return sd_device_new_from_subsystem_sysname(ret, subsys, sysname);
> +        }
> +        default:
> +                return -EINVAL;
> +        }
> +}
> +
> +_public_ int sd_device_get_syspath(sd_device *device, const char **ret) {
> +        assert_return(device, -EINVAL);
> +        assert_return(ret, -EINVAL);
> +
> +        assert(path_startswith(device->syspath, "/sys/"));
> +
> +        *ret = device->syspath;
> +
> +        return 0;
> +}
> +
> +static int device_new_from_child(sd_device **ret, sd_device *child) {
> +        _cleanup_free_ char *path = NULL;
> +        const char *subdir, *syspath;
> +        int r;
> +
> +        assert(ret);
> +        assert(child);
> +
> +        r = sd_device_get_syspath(child, &syspath);
> +        if (r < 0)
> +                return r;
> +
> +        path = strdup(syspath);
> +        if (!path)
> +                return -ENOMEM;
> +        subdir = path + strlen("/sys");
> +
> +        for (;;) {
> +                char *pos;
> +
> +                pos = strrchr(subdir, '/');
> +                if (!pos || pos < subdir + 2)
> +                        break;
> +
> +                *pos = '\0';
> +
> +                r = sd_device_new_from_syspath(ret, path);
> +                if (r < 0)
> +                        continue;
> +
> +                return 0;
> +        }
> +
> +        return -ENOENT;
> +}
> +
> +_public_ int sd_device_get_parent(sd_device *child, sd_device **ret) {
> +
> +        assert_return(ret, -EINVAL);
> +        assert_return(child, -EINVAL);
> +
> +        if (!child->parent_set) {
> +                child->parent_set = true;
> +
> +                (void)device_new_from_child(&child->parent, child);
> +        }
> +
> +        if (!child->parent)
> +                return -ENOENT;
> +
> +        *ret = child->parent;
> +
> +        return 0;
> +}
> +
> +int device_set_subsystem(sd_device *device, const char *_subsystem) {
> +        _cleanup_free_ char *subsystem = NULL;
> +        int r;
> +
> +        assert(device);
> +        assert(_subsystem);
> +
> +        subsystem = strdup(_subsystem);
> +        if (!subsystem)
> +                return -ENOMEM;
> +
> +        r = device_add_property_internal(device, "SUBSYSTEM", subsystem);
> +        if (r < 0)
> +                return r;
> +
> +        free(device->subsystem);
> +        device->subsystem = subsystem;
> +        subsystem = NULL;
> +
> +        device->subsystem_set = true;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_subsystem(sd_device *device, const char **ret) {
> +        assert_return(ret, -EINVAL);
> +        assert_return(device, -EINVAL);
> +
> +        if (!device->subsystem_set) {
> +                _cleanup_free_ char *subsystem = NULL;
> +                const char *syspath;
> +                char *path;
> +                int r;
> +
> +                /* read 'subsystem' link */
> +                r = sd_device_get_syspath(device, &syspath);
> +                if (r < 0)
> +                        return r;
> +
> +                path = strjoina(syspath, "/subsystem");
> +                r = readlink_value(path, &subsystem);
> +                if (r >= 0)
> +                        r = device_set_subsystem(device, subsystem);
> +                /* use implicit names */
> +                else if (path_startswith(device->devpath, "/module/"))
> +                        r = device_set_subsystem(device, "module");
> +                else if (strstr(device->devpath, "/drivers/"))
> +                        r = device_set_subsystem(device, "drivers");
> +                else if (path_startswith(device->devpath, "/subsystem/") ||
> +                         path_startswith(device->devpath, "/class/") ||
> +                         path_startswith(device->devpath, "/buss/"))
> +                        r = device_set_subsystem(device, "subsystem");
> +                if (r < 0)
> +                        return r;
> +
> +                device->subsystem_set = true;
> +        }
> +
> +        *ret = device->subsystem;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_devtype(sd_device *device, const char **devtype) {
> +        int r;
> +
> +        assert(devtype);
> +        assert(device);
> +
> +        r = device_read_uevent_file(device);
> +        if (r < 0)
> +                return r;
> +
> +        *devtype = device->devtype;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_parent_with_subsystem_devtype(sd_device *child, const char *subsystem, const char *devtype, sd_device **ret) {
> +        sd_device *parent = NULL;
> +        int r;
> +
> +        assert_return(child, -EINVAL);
> +        assert_return(subsystem, -EINVAL);
> +
> +        r = sd_device_get_parent(child, &parent);
> +        while (r >= 0) {
> +                const char *parent_subsystem;
> +                const char *parent_devtype;
> +
> +                (void)sd_device_get_subsystem(parent, &parent_subsystem);
> +                if (streq_ptr(parent_subsystem, subsystem)) {
> +                        if (!devtype)
> +                                break;
> +
> +                        (void)sd_device_get_devtype(parent, &parent_devtype);
> +                        if (streq_ptr(parent_devtype, devtype))
> +                                break;
> +                }
> +                r = sd_device_get_parent(parent, &parent);
> +        }
> +
> +        if (r < 0)
> +                return r;
> +
> +        *ret = parent;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_devnum(sd_device *device, dev_t *devnum) {
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(devnum, -EINVAL);
> +
> +        r = device_read_uevent_file(device);
> +        if (r < 0)
> +                return r;
> +
> +        *devnum = device->devnum;
> +
> +        return 0;
> +}
> +
> +int device_set_driver(sd_device *device, const char *_driver) {
> +        char *driver;
> +        int r;
> +
> +        assert(device);
> +        assert(_driver);
> +
> +        driver = strdup(_driver);
> +        if (!driver)
> +                return -ENOMEM;
> +
> +        r = device_add_property_internal(device, "DRIVER", driver);
> +        if (r < 0)
> +                return r;
> +
> +        free(device->driver);
> +        device->driver = driver;
> +
> +        device->driver_set = true;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_driver(sd_device *device, const char **ret) {
> +        assert_return(device, -EINVAL);
> +        assert_return(ret, -EINVAL);
> +
> +        if (!device->driver_set) {
> +                _cleanup_free_ char *driver = NULL;
> +                const char *syspath;
> +                char *path;
> +                int r;
> +
> +                r = sd_device_get_syspath(device, &syspath);
> +                if (r < 0)
> +                        return r;
> +
> +                path = strjoina(syspath, "/driver");
> +                r = readlink_value(path, &driver);
> +                if (r >= 0) {
> +                        r = device_set_driver(device, driver);
> +                        if (r < 0)
> +                                return r;
> +                }
> +        }
> +
> +        *ret = device->driver;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_devpath(sd_device *device, const char **devpath) {
> +        assert_return(device, -EINVAL);
> +        assert_return(devpath, -EINVAL);
> +
> +        assert(device->devpath);
> +        assert(device->devpath[0] == '/');
> +
> +        *devpath = device->devpath;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_devname(sd_device *device, const char **devname) {
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(devname, -EINVAL);
> +
> +        r = device_read_uevent_file(device);
> +        if (r < 0)
> +                return r;
> +
> +        if (!device->devname)
> +                return -ENOENT;
> +
> +        assert(path_startswith(device->devname, "/dev/"));
> +
> +        *devname = device->devname;
> +
> +        return 0;
> +}
> +
> +static int device_set_sysname(sd_device *device) {
> +        _cleanup_free_ char *sysname = NULL;
> +        const char *sysnum;
> +        const char *pos;
> +        size_t len = 0;
> +
> +        pos = strrchr(device->devpath, '/');
> +        if (!pos)
> +                return -EINVAL;
> +        pos ++;
> +
> +        /* devpath is not a root directory */
> +        if (*pos == '\0' || pos <= device->devpath)
> +                return -EINVAL;
> +
> +        sysname = strdup(pos);
> +        if (!sysname)
> +                return -ENOMEM;
> +
> +        /* some devices have '!' in their name, change that to '/' */
> +        while (sysname[len] != '\0') {
> +                if (sysname[len] == '!')
> +                        sysname[len] = '/';
> +
> +                len ++;
> +        }
> +
> +        /* trailing number */
> +        while (len > 0 && isdigit(sysname[--len]))
> +                sysnum = &sysname[len];
> +
> +        if (len == 0)
> +                sysnum = NULL;
> +
> +        free(device->sysname);
> +        device->sysname = sysname;
> +        sysname = NULL;
> +
> +        device->sysnum = sysnum;
> +
> +        device->sysname_set = true;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_sysname(sd_device *device, const char **ret) {
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(ret, -EINVAL);
> +
> +        if (!device->sysname_set) {
> +                r = device_set_sysname(device);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        *ret = device->sysname;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_sysnum(sd_device *device, const char **ret) {
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(ret, -EINVAL);
> +
> +        if (!device->sysname_set) {
> +                r = device_set_sysname(device);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        *ret = device->sysnum;
> +
> +        return 0;
> +}
> +
> +static bool is_valid_tag(const char *tag) {
> +        assert(tag);
> +
> +        return !strchr(tag, ':') && !strchr(tag, ' ');
> +}
> +
> +int device_add_tag(sd_device *device, const char *tag) {
> +        int r;
> +
> +        assert(device);
> +        assert(tag);
> +
> +        if (!is_valid_tag(tag))
> +                return -EINVAL;
> +
> +        r = set_ensure_allocated(&device->tags, &string_hash_ops);
> +        if (r < 0)
> +                return r;
> +
> +        r = set_put_strdup(device->tags, tag);
> +        if (r < 0)
> +                return r;
> +
> +        device->tags_generation ++;
> +        device->property_tags_outdated = true;
> +
> +        return 0;
> +}
> +
> +int device_add_devlink(sd_device *device, const char *devlink) {
> +        int r;
> +
> +        assert(device);
> +        assert(devlink);
> +
> +        r = set_ensure_allocated(&device->devlinks, &string_hash_ops);
> +        if (r < 0)
> +                return r;
> +
> +        r = set_put_strdup(device->devlinks, devlink);
> +        if (r < 0)
> +                return r;
> +
> +        device->devlinks_generation ++;
> +        device->property_devlinks_outdated = true;
> +
> +        return 0;
> +}
> +
> +static int device_add_property_internal_from_string(sd_device *device, const char *str) {
> +        _cleanup_free_ char *key = NULL;
> +        char *value;
> +
> +        assert(device);
> +        assert(str);
> +
> +        key = strdup(str);
> +        if (!key)
> +                return -ENOMEM;
> +
> +        value = strchr(key, '=');
> +        if (!value)
> +                return -EINVAL;
> +
> +        *value = '\0';
> +
> +        if (isempty(++value))
> +                value = NULL;
> +
> +        return device_add_property_internal(device, key, value);
> +}
> +
> +int device_set_usec_initialized(sd_device *device, const char *initialized) {
> +        uint64_t usec_initialized;
> +        int r;
> +
> +        assert(device);
> +        assert(initialized);
> +
> +        r = safe_atou64(initialized, &usec_initialized);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_add_property_internal(device, "USEC_INITIALIZED", initialized);
> +        if (r < 0)
> +                return r;
> +
> +        device->usec_initialized = usec_initialized;
> +
> +        return 0;
> +}
> +
> +static int handle_db_line(sd_device *device, char key, const char *value) {
> +        char *path;
> +        int r;
> +
> +        assert(device);
> +        assert(value);
> +
> +        switch (key) {
> +        case 'G':
> +                r = device_add_tag(device, value);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'S':
> +                path = strjoina("/dev/", value);
> +                r = device_add_devlink(device, path);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'E':
> +                r = device_add_property_internal_from_string(device, value);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'I':
> +                r = device_set_usec_initialized(device, value);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'L':
> +                r = safe_atoi(value, &device->devlink_priority);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        case 'W':
> +                r = safe_atoi(value, &device->watch_handle);
> +                if (r < 0)
> +                        return r;
> +
> +                break;
> +        default:
> +                log_debug("device db: unknown key '%c'", key);
> +        }
> +
> +        return 0;
> +}
> +
> +int device_get_id_filename(sd_device *device, const char **ret) {
> +        assert(device);
> +        assert(ret);
> +
> +        if (!device->id_filename) {
> +                _cleanup_free_ char *id = NULL;
> +                const char *subsystem;
> +                dev_t devnum;
> +                int ifindex, r;
> +
> +                r = sd_device_get_subsystem(device, &subsystem);
> +                if (r < 0)
> +                        return r;
> +
> +                r = sd_device_get_devnum(device, &devnum);
> +                if (r < 0)
> +                        return r;
> +
> +                r = sd_device_get_ifindex(device, &ifindex);
> +                if (r < 0)
> +                        return r;
> +
> +                if (major(devnum) > 0) {
> +                        /* use dev_t -- b259:131072, c254:0 */
> +                        r = asprintf(&id, "%c%u:%u",
> +                                     streq(subsystem, "block") ? 'b' : 'c',
> +                                     major(devnum), minor(devnum));
> +                        if (r < 0)
> +                                return -errno;
> +                } else if (ifindex > 0) {
> +                        /* use netdev ifindex -- n3 */
> +                        r = asprintf(&id, "n%u", ifindex);
> +                        if (r < 0)
> +                                return -errno;
> +                } else {
> +                        /* use $subsys:$sysname -- pci:0000:00:1f.2
> +                         * sysname() has '!' translated, get it from devpath
> +                         */
> +                        const char *sysname;
> +
> +                        sysname = basename(device->devpath);
> +                        if (!sysname)
> +                                return -EINVAL;
> +
> +                        r = asprintf(&id, "+%s:%s", subsystem, sysname);
> +                        if (r < 0)
> +                                return -errno;
> +                }
> +
> +                device->id_filename = id;
> +                id = NULL;
> +        }
> +
> +        *ret = device->id_filename;
> +
> +        return 0;
> +}
> +
> +static int device_read_db(sd_device *device) {
> +        _cleanup_free_ char *db = NULL;
> +        char *path;
> +        const char *id, *value;
> +        char key;
> +        size_t db_len;
> +        unsigned i;
> +        int r;
> +
> +        enum {
> +                PRE_KEY,
> +                KEY,
> +                PRE_VALUE,
> +                VALUE,
> +                INVALID_LINE,
> +        } state = PRE_KEY;
> +
> +        if (device->db_loaded || device->sealed)
> +                return 0;
> +
> +        r = device_get_id_filename(device, &id);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina("/run/udev/data/", id);
> +
> +        r = read_full_file(path, &db, &db_len);
> +        if (r < 0) {
> +                if (r == -ENOENT)
> +                        return 0;
> +                else {
> +                        log_debug("sd-device: failed to read db '%s': %s", path, strerror(-r));
> +                        return r;
> +                }
> +        }
> +
> +        /* devices with a database entry are initialized */
> +        device->is_initialized = true;;
> +
> +        for (i = 0; i < db_len; i++) {
> +                switch (state) {
> +                case PRE_KEY:
> +                        if (!strchr(NEWLINE, db[i])) {
> +                                key = db[i];
> +
> +                                state = KEY;
> +                        }
> +
> +                        break;
> +                case KEY:
> +                        if (db[i] != ':') {
> +                                log_debug("sd-device: ignoring invalid db entry with key '%c'", key);
> +
> +                                state = INVALID_LINE;
> +                        } else {
> +                                db[i] = '\0';
> +
> +                                state = PRE_VALUE;
> +                        }
> +
> +                        break;
> +                case PRE_VALUE:
> +                        value = &db[i];
> +
> +                        state = VALUE;
> +
> +                        break;
> +                case INVALID_LINE:
> +                        if (strchr(NEWLINE, db[i]))
> +                                state = PRE_KEY;
> +
> +                        break;
> +                case VALUE:
> +                        if (strchr(NEWLINE, db[i])) {
> +                                db[i] = '\0';
> +                                r = handle_db_line(device, key, value);
> +                                if (r < 0)
> +                                        log_debug("sd-device: failed to handle db entry '%c:%s': %s", key, value, strerror(-r));
> +
> +                                state = PRE_KEY;
> +                        }
> +
> +                        break;
> +                default:
> +                        assert_not_reached("invalid state when parsing db");
> +                }
> +        }
> +
> +        device->db_loaded = true;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_is_initialized(sd_device *device, int *initialized) {
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(initialized, -EINVAL);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        *initialized = device->is_initialized;
> +
> +        return 0;
> +}
> +
> +_public_ int sd_device_get_usec_since_initialized(sd_device *device, uint64_t *usec) {
> +        usec_t now_ts;
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(usec, -EINVAL);
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        if (!device->is_initialized)
> +                return -EBUSY;
> +
> +        if (!device->usec_initialized)
> +                return -ENODATA;
> +
> +        now_ts = now(clock_boottime_or_monotonic());
> +
> +        if (now_ts < device->usec_initialized)
> +                return -EIO;
> +
> +        *usec = now_ts - device->usec_initialized;
> +
> +        return 0;
> +}
> +
> +_public_ const char *sd_device_get_tag_first(sd_device *device) {
> +        assert_return(device, NULL);
> +
> +        (void) device_read_db(device);
> +
> +        device->tags_iterator_generation = device->tags_generation;
> +        device->tags_iterator = ITERATOR_FIRST;
> +
> +        return set_iterate(device->tags, &device->tags_iterator);
> +}
> +
> +_public_ const char *sd_device_get_tag_next(sd_device *device) {
> +        assert_return(device, NULL);
> +
> +        (void) device_read_db(device);
> +
> +        if (device->tags_iterator_generation != device->tags_generation)
> +                return NULL;
> +
> +        return set_iterate(device->tags, &device->tags_iterator);
> +}
> +
> +_public_ const char *sd_device_get_devlink_first(sd_device *device) {
> +        assert_return(device, NULL);
> +
> +        (void) device_read_db(device);
> +
> +        device->devlinks_iterator_generation = device->devlinks_generation;
> +        device->devlinks_iterator = ITERATOR_FIRST;
> +
> +        return set_iterate(device->devlinks, &device->devlinks_iterator);
> +}
> +
> +_public_ const char *sd_device_get_devlink_next(sd_device *device) {
> +        assert_return(device, NULL);
> +
> +        (void) device_read_db(device);
> +
> +        if (device->devlinks_iterator_generation != device->devlinks_generation)
> +                return NULL;
> +
> +        return set_iterate(device->devlinks, &device->devlinks_iterator);
> +}
> +
> +static int device_properties_prepare(sd_device *device) {
> +        int r;
> +
> +        assert(device);
> +
> +        r = device_read_uevent_file(device);
> +        if (r < 0)
> +                return r;
> +
> +        r = device_read_db(device);
> +        if (r < 0)
> +                return r;
> +
> +        if (device->property_devlinks_outdated) {
> +                char *devlinks = NULL;
> +                const char *devlink;
> +
> +                devlink = sd_device_get_devlink_first(device);
> +                if (devlink)
> +                        devlinks = strdupa(devlink);
> +
> +                while ((devlink = sd_device_get_devlink_next(device)))
> +                        devlinks = strjoina(devlinks, " ", devlink);
> +
> +                r = device_add_property_internal(device, "DEVLINKS", devlinks);
> +                if (r < 0)
> +                        return r;
> +
> +                device->property_devlinks_outdated = false;
> +        }
> +
> +        if (device->property_tags_outdated) {
> +                char *tags = NULL;
> +                const char *tag;
> +
> +                tag = sd_device_get_tag_first(device);
> +                if (tag)
> +                        tags = strjoina(":", tag);
> +
> +                while ((tag = sd_device_get_tag_next(device)))
> +                        tags = strjoina(tags, ":", tag);
> +
> +                tags = strjoina(tags, ":");
> +
> +                r = device_add_property_internal(device, "TAGS", tags);
> +                if (r < 0)
> +                        return r;
> +
> +                device->property_tags_outdated = false;
> +        }
> +
> +        return 0;
> +}
> +
> +_public_ const char *sd_device_get_property_first(sd_device *device, const char **_value) {
> +        const char *key;
> +        const char *value;
> +        int r;
> +
> +        assert_return(device, NULL);
> +
> +        r = device_properties_prepare(device);
> +        if (r < 0)
> +                return NULL;
> +
> +        device->properties_iterator_generation = device->properties_generation;
> +        device->properties_iterator = ITERATOR_FIRST;
> +
> +        value = ordered_hashmap_iterate(device->properties, &device->properties_iterator, (const void**)&key);
> +
> +        if (_value)
> +                *_value = value;
> +
> +        return key;
> +}
> +
> +_public_ const char *sd_device_get_property_next(sd_device *device, const char **_value) {
> +        const char *key;
> +        const char *value;
> +        int r;
> +
> +        assert_return(device, NULL);
> +
> +        r = device_properties_prepare(device);
> +        if (r < 0)
> +                return NULL;
> +
> +        if (device->properties_iterator_generation != device->properties_generation)
> +                return NULL;
> +
> +        value = ordered_hashmap_iterate(device->properties, &device->properties_iterator, (const void**)&key);
> +
> +        if (_value)
> +                *_value = value;
> +
> +        return key;
> +}
> +
> +static int device_sysattrs_read_all(sd_device *device) {
> +        _cleanup_closedir_ DIR *dir = NULL;
> +        const char *syspath;
> +        struct dirent *dent;
> +        int r;
> +
> +        assert(device);
> +
> +        if (device->sysattrs_read)
> +                return 0;
> +
> +        r = sd_device_get_syspath(device, &syspath);
> +        if (r < 0)
> +                return r;
> +
> +        dir = opendir(syspath);
> +        if (!dir)
> +                return -errno;
> +
> +        r = set_ensure_allocated(&device->sysattrs, &string_hash_ops);
> +        if (r < 0)
> +                return r;
> +
> +        for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
> +                _cleanup_free_ char *sysattr = NULL;
> +                char *path;
> +                struct stat statbuf;
> +
> +                /* only handle symlinks and regular files */
> +                if (dent->d_type != DT_LNK && dent->d_type != DT_REG)
> +                        continue;
> +
> +                path = strjoina(syspath, "/", dent->d_name);
> +
> +                if (lstat(path, &statbuf) != 0)
> +                        continue;
> +
> +                if (!(statbuf.st_mode & S_IRUSR))
> +                        continue;
> +
> +                r = set_put_strdup(device->sysattrs, dent->d_name);
> +                if (r < 0)
> +                        return r;
> +        }
> +
> +        device->sysattrs_read = true;
> +
> +        return 0;
> +}
> +
> +_public_ const char *sd_device_get_sysattr_first(sd_device *device) {
> +        int r;
> +
> +        assert_return(device, NULL);
> +
> +        if (!device->sysattrs_read) {
> +                r = device_sysattrs_read_all(device);
> +                if (r < 0) {
> +                        errno = -r;
> +                        return NULL;
> +                }
> +        }
> +
> +        device->sysattrs_iterator = ITERATOR_FIRST;
> +
> +        return set_iterate(device->sysattrs, &device->sysattrs_iterator);
> +}
> +
> +_public_ const char *sd_device_get_sysattr_next(sd_device *device) {
> +        assert_return(device, NULL);
> +
> +        if (!device->sysattrs_read)
> +                return NULL;
> +
> +        return set_iterate(device->sysattrs, &device->sysattrs_iterator);
> +}
> +
> +_public_ int sd_device_has_tag(sd_device *device, const char *tag) {
> +        assert_return(device, -EINVAL);
> +        assert_return(tag, -EINVAL);
> +
> +        (void) device_read_db(device);
> +
> +        return !!set_contains(device->tags, tag);
> +}
> +
> +_public_ int sd_device_get_property_value(sd_device *device, const char *key, const char **_value) {
> +        char *value;
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(key, -EINVAL);
> +        assert_return(_value, -EINVAL);
> +
> +        r = device_properties_prepare(device);
> +        if (r < 0)
> +                return r;
> +
> +        value = ordered_hashmap_get(device->properties, key);
> +        if (!value)
> +                return -ENOENT;
> +
> +        *_value = value;
> +
> +        return 0;
> +}
> +
> +/* replaces the value if it already exists */
> +static int device_add_sysattr_value(sd_device *device, const char *_key, const char *_value) {
> +        _cleanup_free_ char *key = NULL;
> +        _cleanup_free_ char *value = NULL;
> +        int r;
> +
> +        assert(device);
> +        assert(_key);
> +
> +        r = hashmap_ensure_allocated(&device->sysattr_values, &string_hash_ops);
> +        if (r < 0)
> +                return r;
> +
> +        value = hashmap_remove2(device->sysattr_values, _key, (void **)&key);
> +        if (!key) {
> +                key = strdup(_key);
> +                if (!key)
> +                        return -ENOMEM;
> +        }
> +
> +        free(value);
> +        value = NULL;
> +
> +        if (_value) {
> +                value = strdup(_value);
> +                if (!value)
> +                        return -ENOMEM;
> +        }
> +
> +        r = hashmap_put(device->sysattr_values, key, value);
> +        if (r < 0)
> +                return r;
> +
> +        key = NULL;
> +        value = NULL;
> +
> +        return 0;
> +}
> +
> +static int device_get_sysattr_value(sd_device *device, const char *_key, const char **_value) {
> +        const char *key = NULL, *value;
> +
> +        assert(device);
> +        assert(_key);
> +
> +        value = hashmap_get2(device->sysattr_values, _key, (void **) &key);
> +        if (!key)
> +                return -ENOENT;
> +
> +        if (_value)
> +                *_value = value;
> +
> +        return 0;
> +}
> +
> +/* We cache all sysattr lookups. If an attribute does not exist, it is stored
> + * with a NULL value in the cache, otherwise the returned string is stored */
> +_public_ int sd_device_get_sysattr_value(sd_device *device, const char *sysattr, const char **_value) {
> +        _cleanup_free_ char *value = NULL;
> +        const char *syspath, *cached_value = NULL;
> +        char *path;
> +        struct stat statbuf;
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(sysattr, -EINVAL);
> +
> +        /* look for possibly already cached result */
> +        r = device_get_sysattr_value(device, sysattr, &cached_value);
> +        if (r != -ENOENT) {
> +                if (r < 0)
> +                        return r;
> +
> +                if (!cached_value)
> +                        /* we looked up the sysattr before and it did not exist */
> +                        return -ENOENT;
> +
> +                if (_value)
> +                        *_value = cached_value;
> +
> +                return 0;
> +        }
> +
> +        r = sd_device_get_syspath(device, &syspath);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina(syspath, "/", sysattr);
> +        r = lstat(path, &statbuf);
> +        if (r < 0) {
> +                /* remember that we could not access the sysattr */
> +                r = device_add_sysattr_value(device, sysattr, NULL);
> +                if (r < 0)
> +                        return r;
> +
> +                return -ENOENT;
> +        } else if (S_ISLNK(statbuf.st_mode)) {
> +                /* Some core links return only the last element of the target path,
> +                 * these are just values, the paths should not be exposed. */
> +                if (STR_IN_SET(sysattr, "driver", "subsystem", "module")) {
> +                        r = readlink_value(path, &value);
> +                        if (r < 0)
> +                                return r;
> +                } else
> +                        return -EINVAL;
> +        } else if (S_ISDIR(statbuf.st_mode)) {
> +                /* skip directories */
> +                return -EINVAL;
> +        } else if (!(statbuf.st_mode & S_IRUSR)) {
> +                /* skip non-readable files */
> +                return -EPERM;
> +        } else {
> +                size_t size;
> +
> +                /* read attribute value */
> +                r = read_full_file(path, &value, &size);
> +                if (r < 0)
> +                        return r;
> +
> +                /* drop trailing newlines */
> +                while (size > 0 && value[--size] == '\n')
> +                        value[size] = '\0';
> +        }
> +
> +        r = device_add_sysattr_value(device, sysattr, value);
> +        if (r < 0)
> +                return r;
> +
> +        *_value = value;
> +        value = NULL;
> +
> +        return 0;
> +}
> +
> +static void device_remove_sysattr_value(sd_device *device, const char *_key) {
> +        _cleanup_free_ char *key = NULL;
> +        _cleanup_free_ char *value = NULL;
> +
> +        assert(device);
> +        assert(_key);
> +
> +        value = hashmap_remove2(device->sysattr_values, _key, (void **) &key);
> +
> +        return;
> +}
> +
> +/* set the attribute and save it in the cache. If a NULL value is passed the
> + * attribute is cleared from the cache */
> +_public_ int sd_device_set_sysattr_value(sd_device *device, const char *sysattr, char *value) {
> +        _cleanup_close_ int fd = -1;
> +        const char *syspath;
> +        char *path;
> +        struct stat statbuf;
> +        size_t value_len = 0;
> +        ssize_t size;
> +        int r;
> +
> +        assert_return(device, -EINVAL);
> +        assert_return(sysattr, -EINVAL);
> +
> +        if (!value) {
> +                device_remove_sysattr_value(device, sysattr);
> +
> +                return 0;
> +        }
> +
> +        r = sd_device_get_syspath(device, &syspath);
> +        if (r < 0)
> +                return r;
> +
> +        path = strjoina(syspath, "/", sysattr);
> +        r = lstat(path, &statbuf);
> +        if (r < 0) {
> +                r = device_add_sysattr_value(device, sysattr, "");
> +                if (r < 0)
> +                        return r;
> +
> +                return -ENXIO;
> +        }
> +
> +        if (S_ISLNK(statbuf.st_mode))
> +                return -EINVAL;
> +
> +        /* skip directories */
> +        if (S_ISDIR(statbuf.st_mode))
> +                return -EISDIR;
> +
> +        /* skip non-readable files */
> +        if ((statbuf.st_mode & S_IRUSR) == 0)
> +                return -EACCES;
> +
> +        value_len = strlen(value);
> +
> +        /* drop trailing newlines */
> +        while (value_len > 0 && value[--value_len] == '\n')
> +                value[value_len] = '\0';
> +
> +        /* value length is limited to 4k */
> +        if (value_len > 4096)
> +                return -EINVAL;
> +
> +        fd = open(path, O_WRONLY | O_CLOEXEC);
> +        if (fd < 0)
> +                return -errno;
> +
> +        size = write(fd, value, value_len);
> +        if (size < 0)
> +                return -errno;
> +
> +        if ((size_t)size != value_len)
> +                return -EIO;
> +
> +        r = device_add_sysattr_value(device, sysattr, value);
> +        if (r < 0)
> +                return r;
> +
> +        return 0;
> +}
> diff --git a/src/systemd/sd-device.h b/src/systemd/sd-device.h
> new file mode 100644
> index 0000000..d737753
> --- /dev/null
> +++ b/src/systemd/sd-device.h
> @@ -0,0 +1,77 @@
> +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
> +
> +#ifndef foosddevicehfoo
> +#define foosddevicehfoo
> +
> +/***
> +  This file is part of systemd.
> +
> +  Copyright 2008-2012 Kay Sievers <kay at vrfy.org>
> +  Copyright 2014 Tom Gundersen <teg at jklm.no>
> +
> +  systemd is free software; you can redistribute it and/or modify it
> +  under the terms of the GNU Lesser General Public License as published by
> +  the Free Software Foundation; either version 2.1 of the License, or
> +  (at your option) any later version.
> +
> +  systemd is distributed in the hope that it will be useful, but
> +  WITHOUT ANY WARRANTY; without even the implied warranty of
> +  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> +  Lesser General Public License for more details.
> +
> +  You should have received a copy of the GNU Lesser General Public License
> +  along with systemd; If not, see <http://www.gnu.org/licenses/>.
> +***/
> +
> +#include <sys/types.h>
> +#include <stdint.h>
> +
> +#include "_sd-common.h"
> +
> +_SD_BEGIN_DECLARATIONS;
> +
> +typedef struct sd_device sd_device;
> +
> +sd_device *sd_device_ref(sd_device *device);
> +sd_device *sd_device_unref(sd_device *device);
> +
> +int sd_device_new_from_syspath(sd_device **ret, const char *syspath);
> +int sd_device_new_from_devnum(sd_device **ret, char type, dev_t devnum);
> +int sd_device_new_from_subsystem_sysname(sd_device **ret, const char *subsystem, const char *sysname);
> +int sd_device_new_from_device_id(sd_device **ret, const char *id);
> +
> +int sd_device_get_parent(sd_device *child, sd_device **ret);
> +int sd_device_get_parent_with_subsystem_devtype(sd_device *child, const char *subsystem, const char *devtype, sd_device **ret);
> +
> +int sd_device_get_syspath(sd_device *device, const char **ret);
> +int sd_device_get_subsystem(sd_device *device, const char **ret);
> +int sd_device_get_devtype(sd_device *device, const char **ret);
> +int sd_device_get_devnum(sd_device *device, dev_t *devnum);
> +int sd_device_get_ifindex(sd_device *device, int *ifindex);
> +int sd_device_get_driver(sd_device *device, const char **ret);
> +int sd_device_get_devpath(sd_device *device, const char **ret);
> +int sd_device_get_devname(sd_device *device, const char **ret);
> +int sd_device_get_sysname(sd_device *device, const char **ret);
> +int sd_device_get_sysnum(sd_device *device, const char **ret);
> +
> +int sd_device_get_is_initialized(sd_device *device, int *initialized);
> +int sd_device_get_usec_since_initialized(sd_device *device, uint64_t *usec);
> +
> +const char *sd_device_get_tag_first(sd_device *device);
> +const char *sd_device_get_tag_next(sd_device *device);
> +const char *sd_device_get_devlink_first(sd_device *device);
> +const char *sd_device_get_devlink_next(sd_device *device);
> +const char *sd_device_get_property_first(sd_device *device, const char **value);
> +const char *sd_device_get_property_next(sd_device *device, const char **value);
> +const char *sd_device_get_sysattr_first(sd_device *device);
> +const char *sd_device_get_sysattr_next(sd_device *device);
> +
> +int sd_device_has_tag(sd_device *device, const char *tag);
> +int sd_device_get_property_value(sd_device *device, const char *key, const char **value);
> +int sd_device_get_sysattr_value(sd_device *device, const char *sysattr, const char **_value);
> +
> +int sd_device_set_sysattr_value(sd_device *device, const char *sysattr, char *value);
> +
> +_SD_END_DECLARATIONS;
> +
> +#endif
> --
> 2.3.4
>


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