src/udev: continue restoring needed deps

9 files changed, 1928 insertions, 26 deletions

diff --git a/src/shared/acl-util.h b/src/shared/acl-util.h
new file mode 100644
index 0000000000..31fbbcd510
--- /dev/null
+++ b/src/shared/acl-util.h
@@ -0,0 +1,24 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  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 acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry);
diff --git a/src/shared/logind-acl.h b/src/shared/logind-acl.h
new file mode 100644
index 0000000000..ec09843a78
--- /dev/null
+++ b/src/shared/logind-acl.h
@@ -0,0 +1,57 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  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 <stdbool.h>
+#include <libudev.h>
+
+#ifdef HAVE_ACL
+
+int devnode_acl(const char *path,
+                bool flush,
+                bool del, uid_t old_uid,
+                bool add, uid_t new_uid);
+
+int devnode_acl_all(struct udev *udev,
+                    const char *seat,
+                    bool flush,
+                    bool del, uid_t old_uid,
+                    bool add, uid_t new_uid);
+#else
+
+static inline int devnode_acl(const char *path,
+                bool flush,
+                bool del, uid_t old_uid,
+                bool add, uid_t new_uid) {
+        return 0;
+}
+
+static inline int devnode_acl_all(struct udev *udev,
+                                  const char *seat,
+                                  bool flush,
+                                  bool del, uid_t old_uid,
+                                  bool add, uid_t new_uid) {
+        return 0;
+}
+
+#endif
diff --git a/src/udev/sd-daemon.h b/src/shared/sd-daemon.h
index fb7456d50f..fb7456d50f 100644
--- a/src/udev/sd-daemon.h
+++ b/src/shared/sd-daemon.h
diff --git a/src/shared/sd-login.h b/src/shared/sd-login.h
new file mode 100644
index 0000000000..6bd1f2da4a
--- /dev/null
+++ b/src/shared/sd-login.h
@@ -0,0 +1,160 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#ifndef foosdloginhfoo
+#define foosdloginhfoo
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  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>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * A few points:
+ *
+ * Instead of returning an empty string array or empty uid array, we
+ * may return NULL.
+ *
+ * Free the data the library returns with libc free(). String arrays
+ * are NULL terminated and you need to free the array itself in
+ * addition to the strings contained.
+ *
+ * We return error codes as negative errno, kernel-style. 0 or
+ * positive on success.
+ *
+ * These functions access data in /proc, /sys/fs/cgroup and /run. All
+ * of these are virtual file systems, hence the accesses are
+ * relatively cheap.
+ *
+ * See sd-login(3) for more information.
+ */
+
+/* Get session from PID. Note that 'shared' processes of a user are
+ * not attached to a session, but only attached to a user. This will
+ * return an error for system processes and 'shared' processes of a
+ * user. */
+int sd_pid_get_session(pid_t pid, char **session);
+
+/* Get UID of the owner of the session of the PID (or in case the
+ * process is a 'shared' user process the UID of that user is
+ * returned). This will not return the UID of the process, but rather
+ * the UID of the owner of the cgroup the process is in. This will
+ * return an error for system processes. */
+int sd_pid_get_owner_uid(pid_t pid, uid_t *uid);
+
+/* Get systemd unit (i.e. service) name from PID. This will return an
+ * error for non-service processes. */
+int sd_pid_get_unit(pid_t, char **unit);
+
+/* Get state from uid. Possible states: offline, lingering, online, active, closing */
+int sd_uid_get_state(uid_t uid, char**state);
+
+/* Return 1 if uid has session on seat. If require_active is true will
+ * look for active sessions only. */
+int sd_uid_is_on_seat(uid_t uid, int require_active, const char *seat);
+
+/* Return sessions of user. If require_active is true will look for
+ * active sessions only. Returns number of sessions as return
+ * value. If sessions is NULL will just return number of sessions. */
+int sd_uid_get_sessions(uid_t uid, int require_active, char ***sessions);
+
+/* Return seats of user is on. If require_active is true will look for
+ * active seats only.  Returns number of seats. If seats is NULL will
+ * just return number of seats.*/
+int sd_uid_get_seats(uid_t uid, int require_active, char ***seats);
+
+/* Return 1 if the session is a active. */
+int sd_session_is_active(const char *session);
+
+/* Get state from session. Possible states: online, active, closing
+ * (This function is a more generic version of
+ * sd_session_is_active().) */
+int sd_session_get_state(const char *sessio, char **state);
+
+/* Determine user id of session */
+int sd_session_get_uid(const char *session, uid_t *uid);
+
+/* Determine seat of session */
+int sd_session_get_seat(const char *session, char **seat);
+
+/* Determine the (PAM) service name this session was registered by. */
+int sd_session_get_service(const char *session, char **service);
+
+/* Determine the type of this session, i.e. one of "tty", "x11" or "unspecified". */
+int sd_session_get_type(const char *session, char **type);
+
+/* Determine the class of this session, i.e. one of "user", "greeter" or "lock-screen". */
+int sd_session_get_class(const char *session, char **clazz);
+
+/* Determine the X11 display of this session. */
+int sd_session_get_display(const char *session, char **display);
+
+/* Return active session and user of seat */
+int sd_seat_get_active(const char *seat, char **session, uid_t *uid);
+
+/* Return sessions and users on seat. Returns number of sessions as
+ * return value. If sessions is NULL returns only the number of
+ * sessions. */
+int sd_seat_get_sessions(const char *seat, char ***sessions, uid_t **uid, unsigned *n_uids);
+
+/* Return whether the seat is multi-session capable */
+int sd_seat_can_multi_session(const char *seat);
+
+/* Return whether the seat is TTY capable, i.e. suitable for showing console UIs */
+int sd_seat_can_tty(const char *seat);
+
+/* Return whether the seat is graphics capable, i.e. suitable for showing graphical UIs */
+int sd_seat_can_graphical(const char *seat);
+
+/* Get all seats, store in *seats. Returns the number of seats. If
+ * seats is NULL only returns number of seats. */
+int sd_get_seats(char ***seats);
+
+/* Get all sessions, store in *sessions. Returns the number of
+ * sessions. If sessions is NULL only returns number of sessions. */
+int sd_get_sessions(char ***sessions);
+
+/* Get all logged in users, store in *users. Returns the number of
+ * users. If users is NULL only returns the number of users. */
+int sd_get_uids(uid_t **users);
+
+/* Monitor object */
+typedef struct sd_login_monitor sd_login_monitor;
+
+/* Create a new monitor. Category must be NULL, "seat", "session",
+ * "uid" to get monitor events for the specific category (or all). */
+int sd_login_monitor_new(const char *category, sd_login_monitor** ret);
+
+/* Destroys the passed monitor. Returns NULL. */
+sd_login_monitor* sd_login_monitor_unref(sd_login_monitor *m);
+
+/* Flushes the monitor */
+int sd_login_monitor_flush(sd_login_monitor *m);
+
+/* Get FD from monitor */
+int sd_login_monitor_get_fd(sd_login_monitor *m);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/udev/Makefile.am b/src/udev/Makefile.am
index a1e5e3e51a..16fbd42c03 100644
--- a/src/udev/Makefile.am
+++ b/src/udev/Makefile.am
@@ -17,20 +17,7 @@ sbin_PROGRAMS = \
 	udevadm
 
 udevd_SOURCES = \
-	udevd.c \
-	conf-files.c \
-	cgroup-util.c \
-	dev-setup.c \
-	exit-status.c \
-	hashmap.c \
-	label.c \
-	log.c \
-	mkdir.c \
-	path-util.c \
-	set.c \
-	strbuf.c \
-	strv.c \
-	util.c
+	udevd.c
 
 udevd_LDADD = \
 	libudev-core.la
@@ -68,12 +55,24 @@ libudev_core_la_SOURCES = \
 	udev-builtin-kmod.c \
 	udev-builtin-net_id.c \
 	udev-builtin-path_id.c \
-	udev-builtin-usb_id.c
-
-if HAVE_ACL
-libudev_core_la_SOURCES += \
-	udev-builtin-uaccess.c
-endif
+	udev-builtin-usb_id.c \
+	acl-util.c \
+	conf-files.c \
+	cgroup-util.c \
+	dev-setup.c \
+	exit-status.c \
+	hashmap.c \
+	label.c \
+	log.c \
+	logind-acl.c \
+	mkdir.c \
+	path-util.c \
+	sd-daemon.c \
+	sd-login.c \
+	set.c \
+	strbuf.c \
+	strv.c \
+	util.c
 
 libudev_core_la_CFLAGS = \
 	$(AM_CFLAGS) \
@@ -85,6 +84,15 @@ libudev_core_la_LIBADD = \
 	$(BLKID_LIBS) \
 	$(KMOD_LIBS)
 
+if HAVE_ACL
+libudev_core_la_SOURCES += \
+	udev-builtin-uaccess.c
+
+libudev_core_la_LIBADD += \
+        $(ACL_LIBS)
+endif
+
+
 libudev_core_la_CPPFLAGS = \
 	$(AM_CPPFLAGS) \
 	-DFIRMWARE_PATH="$(FIRMWARE_PATH)"
@@ -123,7 +131,8 @@ ata_id_ata_id_SOURCES = \
 	ata_id/ata_id.c
 
 ata_id_ata_id_LDADD = \
-	libudev-private.la
+	$(top_srcdir)/src/libudev/libudev-private.la \
+	libudev-core.la
 
 # ------------------------------------------------------------------------------
 
@@ -134,7 +143,8 @@ cdrom_id_cdrom_id_SOURCES = \
 	cdrom_id/cdrom_id.c
 
 cdrom_id_cdrom_id_LDADD = \
-	libudev.la
+	$(top_srcdir)/src/libudev/libudev-private.la \
+	libudev-core.la
 
 # ------------------------------------------------------------------------------
 
@@ -145,7 +155,8 @@ collect_collect_SOURCES = \
 	collect/collect.c
 
 collect_collect_LDADD = \
-	libudev-private.la
+	$(top_srcdir)/src/libudev/libudev-private.la \
+	libudev-core.la
 
 # ------------------------------------------------------------------------------
 
@@ -159,7 +170,8 @@ scsi_id_scsi_id_SOURCES =\
 	scsi_id/scsi_id.h
 
 scsi_id_scsi_id_LDADD = \
-	libudev-private.la
+	$(top_srcdir)/src/libudev/libudev-private.la \
+	libudev-core.la
 
 EXTRA_DIST += \
 	scsi_id/README
@@ -173,7 +185,8 @@ v4l_id_v4l_id_SOURCES = \
 	v4l_id/v4l_id.c
 
 v4l_id_v4l_id_LDADD = \
-	libudev.la
+	$(top_srcdir)/src/libudev/libudev-private.la \
+	libudev-core.la
 
 # ------------------------------------------------------------------------------
 
@@ -184,7 +197,9 @@ accelerometer_accelerometer_SOURCES = \
 	accelerometer/accelerometer.c
 
 accelerometer_accelerometer_LDADD = \
-	libudev.la -lm
+	$(top_srcdir)/src/libudev/libudev-private.la \
+	libudev-core.la \
+	-lm
 
 # ------------------------------------------------------------------------------
 
diff --git a/src/udev/acl-util.c b/src/udev/acl-util.c
new file mode 100644
index 0000000000..d1eb6f2268
--- /dev/null
+++ b/src/udev/acl-util.c
@@ -0,0 +1,68 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  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 <assert.h>
+#include <sys/acl.h>
+#include <acl/libacl.h>
+#include <errno.h>
+#include <stdbool.h>
+
+#include "acl-util.h"
+
+int acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry) {
+        acl_entry_t i;
+        int found;
+
+        assert(acl);
+        assert(entry);
+
+        for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
+             found > 0;
+             found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
+
+                acl_tag_t tag;
+                uid_t *u;
+                bool b;
+
+                if (acl_get_tag_type(i, &tag) < 0)
+                        return -errno;
+
+                if (tag != ACL_USER)
+                        continue;
+
+                u = acl_get_qualifier(i);
+                if (!u)
+                        return -errno;
+
+                b = *u == uid;
+                acl_free(u);
+
+                if (b) {
+                        *entry = i;
+                        return 1;
+                }
+        }
+
+        if (found < 0)
+                return -errno;
+
+        return 0;
+}
diff --git a/src/udev/logind-acl.c b/src/udev/logind-acl.c
new file mode 100644
index 0000000000..cb045a9928
--- /dev/null
+++ b/src/udev/logind-acl.c
@@ -0,0 +1,248 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  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 <assert.h>
+#include <sys/acl.h>
+#include <acl/libacl.h>
+#include <errno.h>
+#include <string.h>
+
+#include "logind-acl.h"
+#include "util.h"
+#include "acl-util.h"
+
+static int flush_acl(acl_t acl) {
+        acl_entry_t i;
+        int found;
+        bool changed = false;
+
+        assert(acl);
+
+        for (found = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);
+             found > 0;
+             found = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {
+
+                acl_tag_t tag;
+
+                if (acl_get_tag_type(i, &tag) < 0)
+                        return -errno;
+
+                if (tag != ACL_USER)
+                        continue;
+
+                if (acl_delete_entry(acl, i) < 0)
+                        return -errno;
+
+                changed = true;
+        }
+
+        if (found < 0)
+                return -errno;
+
+        return changed;
+}
+
+int devnode_acl(const char *path,
+                bool flush,
+                bool del, uid_t old_uid,
+                bool add, uid_t new_uid) {
+
+        acl_t acl;
+        int r = 0;
+        bool changed = false;
+
+        assert(path);
+
+        acl = acl_get_file(path, ACL_TYPE_ACCESS);
+        if (!acl)
+                return -errno;
+
+        if (flush) {
+
+                r = flush_acl(acl);
+                if (r < 0)
+                        goto finish;
+                if (r > 0)
+                        changed = true;
+
+        } else if (del && old_uid > 0) {
+                acl_entry_t entry;
+
+                r = acl_find_uid(acl, old_uid, &entry);
+                if (r < 0)
+                        goto finish;
+
+                if (r > 0) {
+                        if (acl_delete_entry(acl, entry) < 0) {
+                                r = -errno;
+                                goto finish;
+                        }
+
+                        changed = true;
+                }
+        }
+
+        if (add && new_uid > 0) {
+                acl_entry_t entry;
+                acl_permset_t permset;
+                int rd, wt;
+
+                r = acl_find_uid(acl, new_uid, &entry);
+                if (r < 0)
+                        goto finish;
+
+                if (r == 0) {
+                        if (acl_create_entry(&acl, &entry) < 0) {
+                                r = -errno;
+                                goto finish;
+                        }
+
+                        if (acl_set_tag_type(entry, ACL_USER) < 0 ||
+                            acl_set_qualifier(entry, &new_uid) < 0) {
+                                r = -errno;
+                                goto finish;
+                        }
+                }
+
+                if (acl_get_permset(entry, &permset) < 0) {
+                        r = -errno;
+                        goto finish;
+                }
+
+                rd = acl_get_perm(permset, ACL_READ);
+                if (rd < 0) {
+                        r = -errno;
+                        goto finish;
+                }
+
+                wt = acl_get_perm(permset, ACL_WRITE);
+                if (wt < 0) {
+                        r = -errno;
+                        goto finish;
+                }
+
+                if (!rd || !wt) {
+
+                        if (acl_add_perm(permset, ACL_READ|ACL_WRITE) < 0) {
+                                r = -errno;
+                                goto finish;
+                        }
+
+                        changed = true;
+                }
+        }
+
+        if (!changed)
+                goto finish;
+
+        if (acl_calc_mask(&acl) < 0) {
+                r = -errno;
+                goto finish;
+        }
+
+        if (acl_set_file(path, ACL_TYPE_ACCESS, acl) < 0) {
+                r = -errno;
+                goto finish;
+        }
+
+        r = 0;
+
+finish:
+        acl_free(acl);
+
+        return r;
+}
+
+int devnode_acl_all(struct udev *udev,
+                    const char *seat,
+                    bool flush,
+                    bool del, uid_t old_uid,
+                    bool add, uid_t new_uid) {
+
+        struct udev_list_entry *item = NULL, *first = NULL;
+        struct udev_enumerate *e;
+        int r;
+
+        assert(udev);
+
+        if (isempty(seat))
+                seat = "seat0";
+
+        e = udev_enumerate_new(udev);
+        if (!e)
+                return -ENOMEM;
+
+        /* We can only match by one tag in libudev. We choose
+         * "uaccess" for that. If we could match for two tags here we
+         * could add the seat name as second match tag, but this would
+         * be hardly optimizable in libudev, and hence checking the
+         * second tag manually in our loop is a good solution. */
+
+        r = udev_enumerate_add_match_tag(e, "uaccess");
+        if (r < 0)
+                goto finish;
+
+        r = udev_enumerate_scan_devices(e);
+        if (r < 0)
+                goto finish;
+
+        first = udev_enumerate_get_list_entry(e);
+        udev_list_entry_foreach(item, first) {
+                struct udev_device *d;
+                const char *node, *sn;
+
+                d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
+                if (!d) {
+                        r = -ENOMEM;
+                        goto finish;
+                }
+
+                sn = udev_device_get_property_value(d, "ID_SEAT");
+                if (isempty(sn))
+                        sn = "seat0";
+
+                if (!streq(seat, sn)) {
+                        udev_device_unref(d);
+                        continue;
+                }
+
+                node = udev_device_get_devnode(d);
+                if (!node) {
+                        /* In case people mistag devices with nodes, we need to ignore this */
+                        udev_device_unref(d);
+                        continue;
+                }
+
+                log_debug("Fixing up %s for seat %s...", node, sn);
+
+                r = devnode_acl(node, flush, del, old_uid, add, new_uid);
+                udev_device_unref(d);
+
+                if (r < 0)
+                        goto finish;
+        }
+
+finish:
+        if (e)
+                udev_enumerate_unref(e);
+
+        return r;
+}
diff --git a/src/udev/sd-daemon.c b/src/udev/sd-daemon.c
new file mode 100644
index 0000000000..4801d2cd18
--- /dev/null
+++ b/src/udev/sd-daemon.c
@@ -0,0 +1,536 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  Copyright 2010 Lennart Poettering
+
+  Permission is hereby granted, free of charge, to any person
+  obtaining a copy of this software and associated documentation files
+  (the "Software"), to deal in the Software without restriction,
+  including without limitation the rights to use, copy, modify, merge,
+  publish, distribute, sublicense, and/or sell copies of the Software,
+  and to permit persons to whom the Software is furnished to do so,
+  subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be
+  included in all copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+  BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+  ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+  SOFTWARE.
+***/
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#ifdef __BIONIC__
+#include <linux/fcntl.h>
+#else
+#include <sys/fcntl.h>
+#endif
+#include <netinet/in.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stddef.h>
+#include <limits.h>
+
+#if defined(__linux__)
+#include <mqueue.h>
+#endif
+
+#include "sd-daemon.h"
+
+#if (__GNUC__ >= 4)
+#ifdef SD_EXPORT_SYMBOLS
+/* Export symbols */
+#define _sd_export_ __attribute__ ((visibility("default")))
+#else
+/* Don't export the symbols */
+#define _sd_export_ __attribute__ ((visibility("hidden")))
+#endif
+#else
+#define _sd_export_
+#endif
+
+_sd_export_ int sd_listen_fds(int unset_environment) {
+
+#if defined(DISABLE_SYSTEMD) || !defined(__linux__)
+        return 0;
+#else
+        int r, fd;
+        const char *e;
+        char *p = NULL;
+        unsigned long l;
+
+        e = getenv("LISTEN_PID");
+        if (!e) {
+                r = 0;
+                goto finish;
+        }
+
+        errno = 0;
+        l = strtoul(e, &p, 10);
+
+        if (errno != 0) {
+                r = -errno;
+                goto finish;
+        }
+
+        if (!p || p == e || *p || l <= 0) {
+                r = -EINVAL;
+                goto finish;
+        }
+
+        /* Is this for us? */
+        if (getpid() != (pid_t) l) {
+                r = 0;
+                goto finish;
+        }
+
+        e = getenv("LISTEN_FDS");
+        if (!e) {
+                r = 0;
+                goto finish;
+        }
+
+        errno = 0;
+        l = strtoul(e, &p, 10);
+
+        if (errno != 0) {
+                r = -errno;
+                goto finish;
+        }
+
+        if (!p || p == e || *p) {
+                r = -EINVAL;
+                goto finish;
+        }
+
+        for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + (int) l; fd ++) {
+                int flags;
+
+                flags = fcntl(fd, F_GETFD);
+                if (flags < 0) {
+                        r = -errno;
+                        goto finish;
+                }
+
+                if (flags & FD_CLOEXEC)
+                        continue;
+
+                if (fcntl(fd, F_SETFD, flags | FD_CLOEXEC) < 0) {
+                        r = -errno;
+                        goto finish;
+                }
+        }
+
+        r = (int) l;
+
+finish:
+        if (unset_environment) {
+                unsetenv("LISTEN_PID");
+                unsetenv("LISTEN_FDS");
+        }
+
+        return r;
+#endif
+}
+
+_sd_export_ int sd_is_fifo(int fd, const char *path) {
+        struct stat st_fd;
+
+        if (fd < 0)
+                return -EINVAL;
+
+        if (fstat(fd, &st_fd) < 0)
+                return -errno;
+
+        if (!S_ISFIFO(st_fd.st_mode))
+                return 0;
+
+        if (path) {
+                struct stat st_path;
+
+                if (stat(path, &st_path) < 0) {
+
+                        if (errno == ENOENT || errno == ENOTDIR)
+                                return 0;
+
+                        return -errno;
+                }
+
+                return
+                        st_path.st_dev == st_fd.st_dev &&
+                        st_path.st_ino == st_fd.st_ino;
+        }
+
+        return 1;
+}
+
+_sd_export_ int sd_is_special(int fd, const char *path) {
+        struct stat st_fd;
+
+        if (fd < 0)
+                return -EINVAL;
+
+        if (fstat(fd, &st_fd) < 0)
+                return -errno;
+
+        if (!S_ISREG(st_fd.st_mode) && !S_ISCHR(st_fd.st_mode))
+                return 0;
+
+        if (path) {
+                struct stat st_path;
+
+                if (stat(path, &st_path) < 0) {
+
+                        if (errno == ENOENT || errno == ENOTDIR)
+                                return 0;
+
+                        return -errno;
+                }
+
+                if (S_ISREG(st_fd.st_mode) && S_ISREG(st_path.st_mode))
+                        return
+                                st_path.st_dev == st_fd.st_dev &&
+                                st_path.st_ino == st_fd.st_ino;
+                else if (S_ISCHR(st_fd.st_mode) && S_ISCHR(st_path.st_mode))
+                        return st_path.st_rdev == st_fd.st_rdev;
+                else
+                        return 0;
+        }
+
+        return 1;
+}
+
+static int sd_is_socket_internal(int fd, int type, int listening) {
+        struct stat st_fd;
+
+        if (fd < 0 || type < 0)
+                return -EINVAL;
+
+        if (fstat(fd, &st_fd) < 0)
+                return -errno;
+
+        if (!S_ISSOCK(st_fd.st_mode))
+                return 0;
+
+        if (type != 0) {
+                int other_type = 0;
+                socklen_t l = sizeof(other_type);
+
+                if (getsockopt(fd, SOL_SOCKET, SO_TYPE, &other_type, &l) < 0)
+                        return -errno;
+
+                if (l != sizeof(other_type))
+                        return -EINVAL;
+
+                if (other_type != type)
+                        return 0;
+        }
+
+        if (listening >= 0) {
+                int accepting = 0;
+                socklen_t l = sizeof(accepting);
+
+                if (getsockopt(fd, SOL_SOCKET, SO_ACCEPTCONN, &accepting, &l) < 0)
+                        return -errno;
+
+                if (l != sizeof(accepting))
+                        return -EINVAL;
+
+                if (!accepting != !listening)
+                        return 0;
+        }
+
+        return 1;
+}
+
+union sockaddr_union {
+        struct sockaddr sa;
+        struct sockaddr_in in4;
+        struct sockaddr_in6 in6;
+        struct sockaddr_un un;
+        struct sockaddr_storage storage;
+};
+
+_sd_export_ int sd_is_socket(int fd, int family, int type, int listening) {
+        int r;
+
+        if (family < 0)
+                return -EINVAL;
+
+        r = sd_is_socket_internal(fd, type, listening);
+        if (r <= 0)
+                return r;
+
+        if (family > 0) {
+                union sockaddr_union sockaddr;
+                socklen_t l;
+
+                memset(&sockaddr, 0, sizeof(sockaddr));
+                l = sizeof(sockaddr);
+
+                if (getsockname(fd, &sockaddr.sa, &l) < 0)
+                        return -errno;
+
+                if (l < sizeof(sa_family_t))
+                        return -EINVAL;
+
+                return sockaddr.sa.sa_family == family;
+        }
+
+        return 1;
+}
+
+_sd_export_ int sd_is_socket_inet(int fd, int family, int type, int listening, uint16_t port) {
+        union sockaddr_union sockaddr;
+        socklen_t l;
+        int r;
+
+        if (family != 0 && family != AF_INET && family != AF_INET6)
+                return -EINVAL;
+
+        r = sd_is_socket_internal(fd, type, listening);
+        if (r <= 0)
+                return r;
+
+        memset(&sockaddr, 0, sizeof(sockaddr));
+        l = sizeof(sockaddr);
+
+        if (getsockname(fd, &sockaddr.sa, &l) < 0)
+                return -errno;
+
+        if (l < sizeof(sa_family_t))
+                return -EINVAL;
+
+        if (sockaddr.sa.sa_family != AF_INET &&
+            sockaddr.sa.sa_family != AF_INET6)
+                return 0;
+
+        if (family > 0)
+                if (sockaddr.sa.sa_family != family)
+                        return 0;
+
+        if (port > 0) {
+                if (sockaddr.sa.sa_family == AF_INET) {
+                        if (l < sizeof(struct sockaddr_in))
+                                return -EINVAL;
+
+                        return htons(port) == sockaddr.in4.sin_port;
+                } else {
+                        if (l < sizeof(struct sockaddr_in6))
+                                return -EINVAL;
+
+                        return htons(port) == sockaddr.in6.sin6_port;
+                }
+        }
+
+        return 1;
+}
+
+_sd_export_ int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t length) {
+        union sockaddr_union sockaddr;
+        socklen_t l;
+        int r;
+
+        r = sd_is_socket_internal(fd, type, listening);
+        if (r <= 0)
+                return r;
+
+        memset(&sockaddr, 0, sizeof(sockaddr));
+        l = sizeof(sockaddr);
+
+        if (getsockname(fd, &sockaddr.sa, &l) < 0)
+                return -errno;
+
+        if (l < sizeof(sa_family_t))
+                return -EINVAL;
+
+        if (sockaddr.sa.sa_family != AF_UNIX)
+                return 0;
+
+        if (path) {
+                if (length <= 0)
+                        length = strlen(path);
+
+                if (length <= 0)
+                        /* Unnamed socket */
+                        return l == offsetof(struct sockaddr_un, sun_path);
+
+                if (path[0])
+                        /* Normal path socket */
+                        return
+                                (l >= offsetof(struct sockaddr_un, sun_path) + length + 1) &&
+                                memcmp(path, sockaddr.un.sun_path, length+1) == 0;
+                else
+                        /* Abstract namespace socket */
+                        return
+                                (l == offsetof(struct sockaddr_un, sun_path) + length) &&
+                                memcmp(path, sockaddr.un.sun_path, length) == 0;
+        }
+
+        return 1;
+}
+
+_sd_export_ int sd_is_mq(int fd, const char *path) {
+#if !defined(__linux__)
+        return 0;
+#else
+        struct mq_attr attr;
+
+        if (fd < 0)
+                return -EINVAL;
+
+        if (mq_getattr(fd, &attr) < 0)
+                return -errno;
+
+        if (path) {
+                char fpath[PATH_MAX];
+                struct stat a, b;
+
+                if (path[0] != '/')
+                        return -EINVAL;
+
+                if (fstat(fd, &a) < 0)
+                        return -errno;
+
+                strncpy(stpcpy(fpath, "/dev/mqueue"), path, sizeof(fpath) - 12);
+                fpath[sizeof(fpath)-1] = 0;
+
+                if (stat(fpath, &b) < 0)
+                        return -errno;
+
+                if (a.st_dev != b.st_dev ||
+                    a.st_ino != b.st_ino)
+                        return 0;
+        }
+
+        return 1;
+#endif
+}
+
+_sd_export_ int sd_notify(int unset_environment, const char *state) {
+#if defined(DISABLE_SYSTEMD) || !defined(__linux__) || !defined(SOCK_CLOEXEC)
+        return 0;
+#else
+        int fd = -1, r;
+        struct msghdr msghdr;
+        struct iovec iovec;
+        union sockaddr_union sockaddr;
+        const char *e;
+
+        if (!state) {
+                r = -EINVAL;
+                goto finish;
+        }
+
+        e = getenv("NOTIFY_SOCKET");
+        if (!e)
+                return 0;
+
+        /* Must be an abstract socket, or an absolute path */
+        if ((e[0] != '@' && e[0] != '/') || e[1] == 0) {
+                r = -EINVAL;
+                goto finish;
+        }
+
+        fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
+        if (fd < 0) {
+                r = -errno;
+                goto finish;
+        }
+
+        memset(&sockaddr, 0, sizeof(sockaddr));
+        sockaddr.sa.sa_family = AF_UNIX;
+        strncpy(sockaddr.un.sun_path, e, sizeof(sockaddr.un.sun_path));
+
+        if (sockaddr.un.sun_path[0] == '@')
+                sockaddr.un.sun_path[0] = 0;
+
+        memset(&iovec, 0, sizeof(iovec));
+        iovec.iov_base = (char*) state;
+        iovec.iov_len = strlen(state);
+
+        memset(&msghdr, 0, sizeof(msghdr));
+        msghdr.msg_name = &sockaddr;
+        msghdr.msg_namelen = offsetof(struct sockaddr_un, sun_path) + strlen(e);
+
+        if (msghdr.msg_namelen > sizeof(struct sockaddr_un))
+                msghdr.msg_namelen = sizeof(struct sockaddr_un);
+
+        msghdr.msg_iov = &iovec;
+        msghdr.msg_iovlen = 1;
+
+        if (sendmsg(fd, &msghdr, MSG_NOSIGNAL) < 0) {
+                r = -errno;
+                goto finish;
+        }
+
+        r = 1;
+
+finish:
+        if (unset_environment)
+                unsetenv("NOTIFY_SOCKET");
+
+        if (fd >= 0)
+                close(fd);
+
+        return r;
+#endif
+}
+
+_sd_export_ int sd_notifyf(int unset_environment, const char *format, ...) {
+#if defined(DISABLE_SYSTEMD) || !defined(__linux__)
+        return 0;
+#else
+        va_list ap;
+        char *p = NULL;
+        int r;
+
+        va_start(ap, format);
+        r = vasprintf(&p, format, ap);
+        va_end(ap);
+
+        if (r < 0 || !p)
+                return -ENOMEM;
+
+        r = sd_notify(unset_environment, p);
+        free(p);
+
+        return r;
+#endif
+}
+
+_sd_export_ int sd_booted(void) {
+#if defined(DISABLE_SYSTEMD) || !defined(__linux__)
+        return 0;
+#else
+
+        struct stat a, b;
+
+        /* We simply test whether the systemd cgroup hierarchy is
+         * mounted */
+
+        if (lstat("/sys/fs/cgroup", &a) < 0)
+                return 0;
+
+        if (lstat("/sys/fs/cgroup/systemd", &b) < 0)
+                return 0;
+
+        return a.st_dev != b.st_dev;
+#endif
+}
diff --git a/src/udev/sd-login.c b/src/udev/sd-login.c
new file mode 100644
index 0000000000..45e3bb8dcd
--- /dev/null
+++ b/src/udev/sd-login.c
@@ -0,0 +1,794 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2011 Lennart Poettering
+
+  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 <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/inotify.h>
+
+#include "util.h"
+#include "cgroup-util.h"
+#include "macro.h"
+#include "sd-login.h"
+#include "strv.h"
+
+_public_ int sd_pid_get_session(pid_t pid, char **session) {
+        int r;
+        char *cgroup, *p;
+
+        if (pid < 0)
+                return -EINVAL;
+
+        if (!session)
+                return -EINVAL;
+
+        r = cg_pid_get_cgroup(pid, NULL, &cgroup);
+        if (r < 0)
+                return r;
+
+        if (!startswith(cgroup, "/user/")) {
+                free(cgroup);
+                return -ENOENT;
+        }
+
+        p = strchr(cgroup + 6, '/');
+        if (!p) {
+                free(cgroup);
+                return -ENOENT;
+        }
+
+        p++;
+        if (startswith(p, "shared/") || streq(p, "shared")) {
+                free(cgroup);
+                return -ENOENT;
+        }
+
+        p = strndup(p, strcspn(p, "/"));
+        free(cgroup);
+
+        if (!p)
+                return -ENOMEM;
+
+        *session = p;
+        return 0;
+}
+
+_public_ int sd_pid_get_unit(pid_t pid, char **unit) {
+
+        if (pid < 0)
+                return -EINVAL;
+
+        if (!unit)
+                return -EINVAL;
+
+        return cg_pid_get_unit(pid, unit);
+}
+
+_public_ int sd_pid_get_owner_uid(pid_t pid, uid_t *uid) {
+        int r;
+        char *root, *cgroup, *p, *cc;
+        struct stat st;
+
+        if (pid < 0)
+                return -EINVAL;
+
+        if (!uid)
+                return -EINVAL;
+
+        r = cg_pid_get_cgroup(pid, &root, &cgroup);
+        if (r < 0)
+                return r;
+
+        if (!startswith(cgroup, "/user/")) {
+                free(cgroup);
+                free(root);
+                return -ENOENT;
+        }
+
+        p = strchr(cgroup + 6, '/');
+        if (!p) {
+                free(cgroup);
+                return -ENOENT;
+        }
+
+        p++;
+        p += strcspn(p, "/");
+        *p = 0;
+
+        r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, root, cgroup, &cc);
+        free(root);
+        free(cgroup);
+
+        if (r < 0)
+                return -ENOMEM;
+
+        r = lstat(cc, &st);
+        free(cc);
+
+        if (r < 0)
+                return -errno;
+
+        if (!S_ISDIR(st.st_mode))
+                return -ENOTDIR;
+
+        *uid = st.st_uid;
+        return 0;
+}
+
+_public_ int sd_uid_get_state(uid_t uid, char**state) {
+        char *p, *s = NULL;
+        int r;
+
+        if (!state)
+                return -EINVAL;
+
+        if (asprintf(&p, "/run/systemd/users/%lu", (unsigned long) uid) < 0)
+                return -ENOMEM;
+
+        r = parse_env_file(p, NEWLINE, "STATE", &s, NULL);
+        free(p);
+
+        if (r == -ENOENT) {
+                free(s);
+                s = strdup("offline");
+                if (!s)
+                        return -ENOMEM;
+
+                *state = s;
+                return 0;
+        } else if (r < 0) {
+                free(s);
+                return r;
+        } else if (!s)
+                return -EIO;
+
+        *state = s;
+        return 0;
+}
+
+_public_ int sd_uid_is_on_seat(uid_t uid, int require_active, const char *seat) {
+        char *p, *w, *t, *state, *s = NULL;
+        size_t l;
+        int r;
+        const char *variable;
+
+        if (!seat)
+                return -EINVAL;
+
+        variable = require_active ? "ACTIVE_UID" : "UIDS";
+
+        p = strappend("/run/systemd/seats/", seat);
+        if (!p)
+                return -ENOMEM;
+
+        r = parse_env_file(p, NEWLINE, variable, &s, NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        }
+
+        if (!s)
+                return -EIO;
+
+        if (asprintf(&t, "%lu", (unsigned long) uid) < 0) {
+                free(s);
+                return -ENOMEM;
+        }
+
+        FOREACH_WORD(w, l, s, state) {
+                if (strncmp(t, w, l) == 0) {
+                        free(s);
+                        free(t);
+
+                        return 1;
+                }
+        }
+
+        free(s);
+        free(t);
+
+        return 0;
+}
+
+static int uid_get_array(uid_t uid, const char *variable, char ***array) {
+        char *p, *s = NULL;
+        char **a;
+        int r;
+
+        if (asprintf(&p, "/run/systemd/users/%lu", (unsigned long) uid) < 0)
+                return -ENOMEM;
+
+        r = parse_env_file(p, NEWLINE,
+                           variable, &s,
+                           NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+
+                if (r == -ENOENT) {
+                        if (array)
+                                *array = NULL;
+                        return 0;
+                }
+
+                return r;
+        }
+
+        if (!s) {
+                if (array)
+                        *array = NULL;
+                return 0;
+        }
+
+        a = strv_split(s, " ");
+        free(s);
+
+        if (!a)
+                return -ENOMEM;
+
+        strv_uniq(a);
+        r = strv_length(a);
+
+        if (array)
+                *array = a;
+        else
+                strv_free(a);
+
+        return r;
+}
+
+_public_ int sd_uid_get_sessions(uid_t uid, int require_active, char ***sessions) {
+        return uid_get_array(
+                        uid,
+                        require_active == 0 ? "ONLINE_SESSIONS" :
+                        require_active > 0  ? "ACTIVE_SESSIONS" :
+                                              "SESSIONS",
+                        sessions);
+}
+
+_public_ int sd_uid_get_seats(uid_t uid, int require_active, char ***seats) {
+        return uid_get_array(
+                        uid,
+                        require_active == 0 ? "ONLINE_SEATS" :
+                        require_active > 0  ? "ACTIVE_SEATS" :
+                                              "SEATS",
+                        seats);
+}
+
+static int file_of_session(const char *session, char **_p) {
+        char *p;
+        int r;
+
+        assert(_p);
+
+        if (session)
+                p = strappend("/run/systemd/sessions/", session);
+        else {
+                char *buf;
+
+                r = sd_pid_get_session(0, &buf);
+                if (r < 0)
+                        return r;
+
+                p = strappend("/run/systemd/sessions/", buf);
+                free(buf);
+        }
+
+        if (!p)
+                return -ENOMEM;
+
+        *_p = p;
+        return 0;
+}
+
+_public_ int sd_session_is_active(const char *session) {
+        int r;
+        char *p, *s = NULL;
+
+        r = file_of_session(session, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE, "ACTIVE", &s, NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        }
+
+        if (!s)
+                return -EIO;
+
+        r = parse_boolean(s);
+        free(s);
+
+        return r;
+}
+
+_public_ int sd_session_get_state(const char *session, char **state) {
+        char *p, *s = NULL;
+        int r;
+
+        if (!state)
+                return -EINVAL;
+
+        r = file_of_session(session, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE, "STATE", &s, NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        } else if (!s)
+                return -EIO;
+
+        *state = s;
+        return 0;
+}
+
+_public_ int sd_session_get_uid(const char *session, uid_t *uid) {
+        int r;
+        char *p, *s = NULL;
+
+        if (!uid)
+                return -EINVAL;
+
+        r = file_of_session(session, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE, "UID", &s, NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        }
+
+        if (!s)
+                return -EIO;
+
+        r = parse_uid(s, uid);
+        free(s);
+
+        return r;
+}
+
+static int session_get_string(const char *session, const char *field, char **value) {
+        char *p, *s = NULL;
+        int r;
+
+        if (!value)
+                return -EINVAL;
+
+        r = file_of_session(session, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE, field, &s, NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        }
+
+        if (isempty(s))
+                return -ENOENT;
+
+        *value = s;
+        return 0;
+}
+
+_public_ int sd_session_get_seat(const char *session, char **seat) {
+        return session_get_string(session, "SEAT", seat);
+}
+
+_public_ int sd_session_get_service(const char *session, char **service) {
+        return session_get_string(session, "SERVICE", service);
+}
+
+_public_ int sd_session_get_type(const char *session, char **type) {
+        return session_get_string(session, "TYPE", type);
+}
+
+_public_ int sd_session_get_class(const char *session, char **class) {
+        return session_get_string(session, "CLASS", class);
+}
+
+_public_ int sd_session_get_display(const char *session, char **display) {
+        return session_get_string(session, "DISPLAY", display);
+}
+
+static int file_of_seat(const char *seat, char **_p) {
+        char *p;
+        int r;
+
+        assert(_p);
+
+        if (seat)
+                p = strappend("/run/systemd/seats/", seat);
+        else {
+                char *buf;
+
+                r = sd_session_get_seat(NULL, &buf);
+                if (r < 0)
+                        return r;
+
+                p = strappend("/run/systemd/seats/", buf);
+                free(buf);
+        }
+
+        if (!p)
+                return -ENOMEM;
+
+        *_p = p;
+        return 0;
+}
+
+_public_ int sd_seat_get_active(const char *seat, char **session, uid_t *uid) {
+        char *p, *s = NULL, *t = NULL;
+        int r;
+
+        if (!session && !uid)
+                return -EINVAL;
+
+        r = file_of_seat(seat, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE,
+                           "ACTIVE", &s,
+                           "ACTIVE_UID", &t,
+                           NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                free(t);
+                return r;
+        }
+
+        if (session && !s)  {
+                free(t);
+                return -ENOENT;
+        }
+
+        if (uid && !t) {
+                free(s);
+                return -ENOENT;
+        }
+
+        if (uid && t) {
+                r = parse_uid(t, uid);
+                if (r < 0) {
+                        free(t);
+                        free(s);
+                        return r;
+                }
+        }
+
+        free(t);
+
+        if (session && s)
+                *session = s;
+        else
+                free(s);
+
+        return 0;
+}
+
+_public_ int sd_seat_get_sessions(const char *seat, char ***sessions, uid_t **uids, unsigned *n_uids) {
+        char *p, *s = NULL, *t = NULL, **a = NULL;
+        uid_t *b = NULL;
+        unsigned n = 0;
+        int r;
+
+        r = file_of_seat(seat, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE,
+                           "SESSIONS", &s,
+                           "ACTIVE_SESSIONS", &t,
+                           NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                free(t);
+                return r;
+        }
+
+        if (s) {
+                a = strv_split(s, " ");
+                if (!a) {
+                        free(s);
+                        free(t);
+                        return -ENOMEM;
+                }
+        }
+
+        free(s);
+
+        if (uids && t) {
+                char *w, *state;
+                size_t l;
+
+                FOREACH_WORD(w, l, t, state)
+                        n++;
+
+                if (n == 0)
+                        b = NULL;
+                else {
+                        unsigned i = 0;
+
+                        b = new(uid_t, n);
+                        if (!b) {
+                                strv_free(a);
+                                return -ENOMEM;
+                        }
+
+                        FOREACH_WORD(w, l, t, state) {
+                                char *k;
+
+                                k = strndup(w, l);
+                                if (!k) {
+                                        free(t);
+                                        free(b);
+                                        strv_free(a);
+                                        return -ENOMEM;
+                                }
+
+                                r = parse_uid(k, b + i);
+                                free(k);
+                                if (r < 0)
+                                        continue;
+
+                                i++;
+                        }
+                }
+        }
+
+        free(t);
+
+        r = strv_length(a);
+
+        if (sessions)
+                *sessions = a;
+        else
+                strv_free(a);
+
+        if (uids)
+                *uids = b;
+
+        if (n_uids)
+                *n_uids = n;
+
+        return r;
+}
+
+static int seat_get_can(const char *seat, const char *variable) {
+        char *p, *s = NULL;
+        int r;
+
+        r = file_of_seat(seat, &p);
+        if (r < 0)
+                return r;
+
+        r = parse_env_file(p, NEWLINE,
+                           variable, &s,
+                           NULL);
+        free(p);
+
+        if (r < 0) {
+                free(s);
+                return r;
+        }
+
+        if (s) {
+                r = parse_boolean(s);
+                free(s);
+        } else
+                r = 0;
+
+        return r;
+}
+
+_public_ int sd_seat_can_multi_session(const char *seat) {
+        return seat_get_can(seat, "CAN_MULTI_SESSION");
+}
+
+_public_ int sd_seat_can_tty(const char *seat) {
+        return seat_get_can(seat, "CAN_TTY");
+}
+
+_public_ int sd_seat_can_graphical(const char *seat) {
+        return seat_get_can(seat, "CAN_GRAPHICAL");
+}
+
+_public_ int sd_get_seats(char ***seats) {
+        return get_files_in_directory("/run/systemd/seats/", seats);
+}
+
+_public_ int sd_get_sessions(char ***sessions) {
+        return get_files_in_directory("/run/systemd/sessions/", sessions);
+}
+
+_public_ int sd_get_uids(uid_t **users) {
+        DIR *d;
+        int r = 0;
+        unsigned n = 0;
+        uid_t *l = NULL;
+
+        d = opendir("/run/systemd/users/");
+        if (!d)
+                return -errno;
+
+        for (;;) {
+                struct dirent *de;
+                union dirent_storage buf;
+                int k;
+                uid_t uid;
+
+                k = readdir_r(d, &buf.de, &de);
+                if (k != 0) {
+                        r = -k;
+                        goto finish;
+                }
+
+                if (!de)
+                        break;
+
+                dirent_ensure_type(d, de);
+
+                if (!dirent_is_file(de))
+                        continue;
+
+                k = parse_uid(de->d_name, &uid);
+                if (k < 0)
+                        continue;
+
+                if (users) {
+                        if ((unsigned) r >= n) {
+                                uid_t *t;
+
+                                n = MAX(16, 2*r);
+                                t = realloc(l, sizeof(uid_t) * n);
+                                if (!t) {
+                                        r = -ENOMEM;
+                                        goto finish;
+                                }
+
+                                l = t;
+                        }
+
+                        assert((unsigned) r < n);
+                        l[r++] = uid;
+                } else
+                        r++;
+        }
+
+finish:
+        if (d)
+                closedir(d);
+
+        if (r >= 0) {
+                if (users)
+                        *users = l;
+        } else
+                free(l);
+
+        return r;
+}
+
+static inline int MONITOR_TO_FD(sd_login_monitor *m) {
+        return (int) (unsigned long) m - 1;
+}
+
+static inline sd_login_monitor* FD_TO_MONITOR(int fd) {
+        return (sd_login_monitor*) (unsigned long) (fd + 1);
+}
+
+_public_ int sd_login_monitor_new(const char *category, sd_login_monitor **m) {
+        int fd, k;
+        bool good = false;
+
+        if (!m)
+                return -EINVAL;
+
+        fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
+        if (fd < 0)
+                return errno;
+
+        if (!category || streq(category, "seat")) {
+                k = inotify_add_watch(fd, "/run/systemd/seats/", IN_MOVED_TO|IN_DELETE);
+                if (k < 0) {
+                        close_nointr_nofail(fd);
+                        return -errno;
+                }
+
+                good = true;
+        }
+
+        if (!category || streq(category, "session")) {
+                k = inotify_add_watch(fd, "/run/systemd/sessions/", IN_MOVED_TO|IN_DELETE);
+                if (k < 0) {
+                        close_nointr_nofail(fd);
+                        return -errno;
+                }
+
+                good = true;
+        }
+
+        if (!category || streq(category, "uid")) {
+                k = inotify_add_watch(fd, "/run/systemd/users/", IN_MOVED_TO|IN_DELETE);
+                if (k < 0) {
+                        close_nointr_nofail(fd);
+                        return -errno;
+                }
+
+                good = true;
+        }
+
+        if (!good) {
+                close_nointr(fd);
+                return -EINVAL;
+        }
+
+        *m = FD_TO_MONITOR(fd);
+        return 0;
+}
+
+_public_ sd_login_monitor* sd_login_monitor_unref(sd_login_monitor *m) {
+        int fd;
+
+        if (!m)
+                return NULL;
+
+        fd = MONITOR_TO_FD(m);
+        close_nointr(fd);
+
+        return NULL;
+}
+
+_public_ int sd_login_monitor_flush(sd_login_monitor *m) {
+
+        if (!m)
+                return -EINVAL;
+
+        return flush_fd(MONITOR_TO_FD(m));
+}
+
+_public_ int sd_login_monitor_get_fd(sd_login_monitor *m) {
+
+        if (!m)
+                return -EINVAL;
+
+        return MONITOR_TO_FD(m);
+}