logind: implement GC

src/logind-seat.c

@@ -48,21 +48,23 @@ Seat *seat_new(Manager *m, const char *id) {
         }
 
         s->id = file_name_from_path(s->state_file);
+        s->manager = m;
 
         if (hashmap_put(m->seats, s->id, s) < 0) {
-                free(s->id);
+                free(s->state_file);
                 free(s);
                 return NULL;
         }
 
-        s->manager = m;
-
         return s;
 }
 
 void seat_free(Seat *s) {
         assert(s);
 
+        if (s->in_gc_queue)
+                LIST_REMOVE(Seat, gc_queue, s->manager->seat_gc_queue, s);
+
         while (s->sessions)
                 session_free(s->sessions);
 
@@ -73,25 +75,33 @@ void seat_free(Seat *s) {
 
         hashmap_remove(s->manager->seats, s->id);
 
-        free(s->state_file);
+        if (s->state_file) {
+                unlink(s->state_file);
+                free(s->state_file);
+        }
+
         free(s);
 }
 
 int seat_save(Seat *s) {
-        FILE *f;
         int r;
+        FILE *f;
+        char *temp_path;
 
         assert(s);
 
         r = safe_mkdir("/run/systemd/seat", 0755, 0, 0);
         if (r < 0)
-                return r;
+                goto finish;
 
-        f = fopen(s->state_file, "we");
+        r = fopen_temporary(s->state_file, &f, &temp_path);
-        if (!f)
+        if (r < 0)
-                return -errno;
+                goto finish;
+
+        fchmod(fileno(f), 0644);
 
         fprintf(f,
+                "# This is private data. Do not parse.\n"
                 "IS_VTCONSOLE=%i\n",
                 s->manager->vtconsole == s);
 
@@ -107,28 +117,45 @@ int seat_save(Seat *s) {
 
         if (s->sessions) {
                 Session *i;
-                fputs("OTHER_UIDS=", f);
 
+                fputs("OTHER=", f);
                 LIST_FOREACH(sessions_by_seat, i, s->sessions) {
-                        assert(i->user);
-
                         if (i == s->active)
                                 continue;
 
                         fprintf(f,
-                                "%s%lu",
+                                "%s%c",
-                                i == s->sessions ? "" : " ",
+                                i->id,
-                                (unsigned long) i->user->uid);
+                                i->sessions_by_seat_next ? ' ' : '\n');
+                }
+
+                fputs("OTHER_UIDS=", f);
+                LIST_FOREACH(sessions_by_seat, i, s->sessions) {
+                        if (i == s->active)
+                                continue;
+
+                        fprintf(f,
+                                "%lu%c",
+                                (unsigned long) i->user->uid,
+                                i->sessions_by_seat_next ? ' ' : '\n');
                 }
         }
 
         fflush(f);
-        if (ferror(f)) {
+
+        if (ferror(f) || rename(temp_path, s->state_file) < 0) {
                 r = -errno;
                 unlink(s->state_file);
+                unlink(temp_path);
         }
 
         fclose(f);
+        free(temp_path);
+
+finish:
+        if (r < 0)
+                log_error("Failed to save seat data for %s: %s", s->id, strerror(-r));
+
         return r;
 }
 
@@ -158,7 +185,7 @@ static int vt_allocate(int vtnr) {
         return r;
 }
 
-int seat_preallocate_vts(Seat *s) {
+static int seat_preallocate_vts(Seat *s) {
         int i, r = 0;
 
         assert(s);
@@ -174,8 +201,10 @@ int seat_preallocate_vts(Seat *s) {
                 int q;
 
                 q = vt_allocate(i);
-                if (r >= 0 && q < 0)
+                if (q < 0) {
+                        log_error("Failed to preallocate VT %i: %s", i, strerror(-q));
                         r = q;
+                }
         }
 
         return r;
@@ -199,44 +228,122 @@ int seat_apply_acls(Seat *s, Session *old_active) {
 }
 
 int seat_active_vt_changed(Seat *s, int vtnr) {
-        Session *i;
+        Session *i, *new_active = NULL, *old_active;
-        Session *old_active;
 
         assert(s);
         assert(vtnr >= 1);
-        assert(s->manager->vtconsole == s);
 
-        old_active = s->active;
+        if (s->manager->vtconsole != s)
-        s->active = NULL;
+                return -EINVAL;
+
+        log_debug("VT changed to %i", vtnr);
 
         LIST_FOREACH(sessions_by_seat, i, s->sessions)
                 if (i->vtnr == vtnr) {
-                        s->active = i;
+                        new_active = i;
                         break;
                 }
 
-        if (old_active == s->active)
+        if (new_active == s->active)
                 return 0;
 
+        old_active = s->active;
+        s->active = new_active;
+
         seat_apply_acls(s, old_active);
         manager_spawn_autovt(s->manager, vtnr);
 
         return 0;
 }
 
+int seat_read_active_vt(Seat *s) {
+        char t[64];
+        ssize_t k;
+        int r, vtnr;
+
+        assert(s);
+
+        if (s->manager->vtconsole != s)
+                return 0;
+
+        lseek(s->manager->console_active_fd, SEEK_SET, 0);
+
+        k = read(s->manager->console_active_fd, t, sizeof(t)-1);
+        if (k <= 0) {
+                log_error("Failed to read current console: %s", k < 0 ? strerror(-errno) : "EOF");
+                return k < 0 ? -errno : -EIO;
+        }
+
+        t[k] = 0;
+        truncate_nl(t);
+
+        if (!startswith(t, "tty")) {
+                log_error("Hm, /sys/class/tty/tty0/active is badly formatted.");
+                return -EIO;
+        }
+
+        r = safe_atoi(t+3, &vtnr);
+        if (r < 0) {
+                log_error("Failed to parse VT number %s", t+3);
+                return r;
+        }
+
+        if (vtnr <= 0) {
+                log_error("VT number invalid: %s", t+3);
+                return -EIO;
+        }
+
+        return seat_active_vt_changed(s, vtnr);
+}
+
+int seat_start(Seat *s) {
+        assert(s);
+
+        /* Initialize VT magic stuff */
+        seat_preallocate_vts(s);
+
+        /* Read current VT */
+        seat_read_active_vt(s);
+
+        /* Save seat data */
+        seat_save(s);
+
+        return 0;
+}
+
 int seat_stop(Seat *s) {
         Session *session;
-        int r = 0;
+        int r = 0, k;
 
         assert(s);
 
         LIST_FOREACH(sessions_by_seat, session, s->sessions) {
-                int k;
-
                 k = session_stop(session);
                 if (k < 0)
                         r = k;
         }
 
+        seat_save(s);
+        seat_add_to_gc_queue(s);
+
         return r;
 }
+
+int seat_check_gc(Seat *s) {
+        assert(s);
+
+        if (s->manager->vtconsole == s)
+                return 1;
+
+        return !!s->devices;
+}
+
+void seat_add_to_gc_queue(Seat *s) {
+        assert(s);
+
+        if (s->in_gc_queue)
+                return;
+
+        LIST_PREPEND(Seat, gc_queue, s->manager->seat_gc_queue, s);
+        s->in_gc_queue = true;
+}

src/logind-seat.h

@@ -40,15 +40,26 @@ struct Seat {
 
         Session *active;
         LIST_HEAD(Session, sessions);
+
+        bool in_gc_queue:1;
+
+        LIST_FIELDS(Seat, gc_queue);
 };
 
 Seat *seat_new(Manager *m, const char *id);
 void seat_free(Seat *s);
-int seat_preallocate_vts(Seat *s);
+
-int seat_active_vt_changed(Seat *s, int vtnr);
-int seat_apply_acls(Seat *s, Session *old_active);
-int seat_stop(Seat *s);
 int seat_save(Seat *s);
 int seat_load(Seat *s);
 
+int seat_apply_acls(Seat *s, Session *old_active);
+int seat_active_vt_changed(Seat *s, int vtnr);
+int seat_read_active_vt(Seat *s);
+
+int seat_start(Seat *s);
+int seat_stop(Seat *s);
+
+int seat_check_gc(Seat *s);
+void seat_add_to_gc_queue(Seat *s);
+
 #endif

src/logind-session.c

@@ -34,7 +34,7 @@ Session* session_new(Manager *m, User *u, const char *id) {
         assert(m);
         assert(id);
 
-        s = new(Session, 1);
+        s = new0(Session, 1);
         if (!s)
                 return NULL;
 
@@ -56,7 +56,7 @@ Session* session_new(Manager *m, User *u, const char *id) {
         s->pipe_fd = -1;
         s->user = u;
 
-        dual_timestamp_get(&s->timestamp);
+        LIST_PREPEND(Session, sessions_by_user, u->sessions, s);
 
         return s;
 }
@@ -64,6 +64,9 @@ Session* session_new(Manager *m, User *u, const char *id) {
 void session_free(Session *s) {
         assert(s);
 
+        if (s->in_gc_queue)
+                LIST_REMOVE(Session, gc_queue, s->manager->session_gc_queue, s);
+
         if (s->user) {
                 LIST_REMOVE(Session, sessions_by_user, s->user->sessions, s);
 
@@ -83,26 +86,33 @@ void session_free(Session *s) {
 
         hashmap_remove(s->manager->sessions, s->id);
 
-        free(s->state_file);
+        if (s->state_file) {
+                unlink(s->state_file);
+                free(s->state_file);
+        }
+
         free(s);
 }
 
 int session_save(Session *s) {
         FILE *f;
         int r = 0;
+        char *temp_path;
 
         assert(s);
 
         r = safe_mkdir("/run/systemd/session", 0755, 0, 0);
         if (r < 0)
-                return r;
+                goto finish;
 
-        f = fopen(s->state_file, "we");
+        r = fopen_temporary(s->state_file, &f, &temp_path);
-        if (!f)
+        if (r < 0)
-                return -errno;
+                goto finish;
 
         assert(s->user);
 
+        fchmod(fileno(f), 0644);
+
         fprintf(f,
                 "# This is private data. Do not parse.\n"
                 "UID=%lu\n"
@@ -157,12 +167,20 @@ int session_save(Session *s) {
                         (unsigned long long) s->audit_id);
 
         fflush(f);
-        if (ferror(f)) {
+
+        if (ferror(f) || rename(temp_path, s->state_file) < 0) {
                 r = -errno;
                 unlink(s->state_file);
+                unlink(temp_path);
         }
 
         fclose(f);
+        free(temp_path);
+
+finish:
+        if (r < 0)
+                log_error("Failed to save session data for %s: %s", s->id, strerror(-r));
+
         return r;
 }
 
@@ -196,10 +214,7 @@ int session_activate(Session *s) {
         old_active = s->seat->active;
         s->seat->active = s;
 
-        seat_apply_acls(s->seat, old_active);
+        return seat_apply_acls(s->seat, old_active);
-        manager_spawn_autovt(s->manager, s->vtnr);
-
-        return 0;
 }
 
 bool x11_display_is_local(const char *display) {
@@ -333,11 +348,6 @@ int session_start(Session *s) {
         assert(s);
         assert(s->user);
 
-        /* Create user first */
-        r = user_start(s->user);
-        if (r < 0)
-                return r;
-
         /* Create cgroup */
         r = session_create_cgroup(s);
         if (r < 0)
@@ -345,6 +355,12 @@ int session_start(Session *s) {
 
         /* Create X11 symlink */
         session_link_x11_socket(s);
+
+        /* Save session data */
+        session_save(s);
+
+        dual_timestamp_get(&s->timestamp);
+
         return 0;
 }
 
@@ -429,6 +445,8 @@ int session_stop(Session *s) {
         /* Remove X11 symlink */
         session_unlink_x11_socket(s);
 
+        session_save(s);
+
         return r;
 }
 
@@ -452,7 +470,7 @@ int session_check_gc(Session *s) {
                 if (r < 0)
                         return r;
 
-                if (r <= 0)
+                if (r == 0)
                         return 1;
         }
 
@@ -469,6 +487,16 @@ int session_check_gc(Session *s) {
         return 0;
 }
 
+void session_add_to_gc_queue(Session *s) {
+        assert(s);
+
+        if (s->in_gc_queue)
+                return;
+
+        LIST_PREPEND(Session, gc_queue, s->manager->session_gc_queue, s);
+        s->in_gc_queue = true;
+}
+
 static const char* const session_type_table[_SESSION_TYPE_MAX] = {
         [SESSION_TERMINAL] = "terminal",
         [SESSION_X11] = "x11"

src/logind-session.h

@@ -66,17 +66,21 @@ struct Session {
         char *cgroup_path;
         char **controllers, **reset_controllers;
 
-        bool kill_processes;
+        bool kill_processes:1;
+        bool in_gc_queue:1;
 
         LIST_FIELDS(Session, sessions_by_user);
         LIST_FIELDS(Session, sessions_by_seat);
+
+        LIST_FIELDS(Session, gc_queue);
 };
 
 Session *session_new(Manager *m, User *u, const char *id);
 void session_free(Session *s);
+int session_check_gc(Session *s);
+void session_add_to_gc_queue(Session *s);
 int session_activate(Session *s);
 bool session_is_active(Session *s);
-int session_check_gc(Session *s);
 int session_start(Session *s);
 int session_stop(Session *s);
 int session_save(Session *s);

src/logind-user.c

@@ -35,7 +35,7 @@ User* user_new(Manager *m, uid_t uid, gid_t gid, const char *name) {
         assert(m);
         assert(name);
 
-        u = new(User, 1);
+        u = new0(User, 1);
         if (!u)
                 return NULL;
 
@@ -68,6 +68,9 @@ User* user_new(Manager *m, uid_t uid, gid_t gid, const char *name) {
 void user_free(User *u) {
         assert(u);
 
+        if (u->in_gc_queue)
+                LIST_REMOVE(User, gc_queue, u->manager->user_gc_queue, u);
+
         while (u->sessions)
                 session_free(u->sessions);
 
@@ -79,26 +82,35 @@ void user_free(User *u) {
         hashmap_remove(u->manager->users, ULONG_TO_PTR((unsigned long) u->uid));
 
         free(u->name);
-        free(u->state_file);
+
+        if (u->state_file) {
+                unlink(u->state_file);
+                free(u->state_file);
+        }
+
         free(u);
 }
 
 int user_save(User *u) {
         FILE *f;
         int r;
+        char *temp_path;
 
         assert(u);
         assert(u->state_file);
 
         r = safe_mkdir("/run/systemd/user", 0755, 0, 0);
         if (r < 0)
-                return r;
+                goto finish;
 
-        f = fopen(u->state_file, "we");
+        r = fopen_temporary(u->state_file, &f, &temp_path);
-        if (!f)
+        if (r < 0)
-                return -errno;
+                goto finish;
+
+        fchmod(fileno(f), 0644);
 
         fprintf(f,
+                "# This is private data. Do not parse.\n"
                 "NAME=%s\n"
                 "STATE=%s\n",
                 u->name,
@@ -125,12 +137,20 @@ int user_save(User *u) {
                         u->display->id);
 
         fflush(f);
-        if (ferror(f)) {
+
+        if (ferror(f) || rename(temp_path, u->state_file) < 0) {
                 r = -errno;
                 unlink(u->state_file);
+                unlink(temp_path);
         }
 
         fclose(f);
+        free(temp_path);
+
+finish:
+        if (r < 0)
+                log_error("Failed to save user data for %s: %s", u->name, strerror(-r));
+
         return r;
 }
 
@@ -260,6 +280,9 @@ int user_start(User *u) {
         if (r < 0)
                 return r;
 
+        /* Save new user data */
+        user_save(u);
+
         dual_timestamp_get(&u->timestamp);
 
         return 0;
@@ -395,6 +418,16 @@ int user_check_gc(User *u) {
         return 0;
 }
 
+void user_add_to_gc_queue(User *u) {
+        assert(u);
+
+        if (u->in_gc_queue)
+                return;
+
+        LIST_PREPEND(User, gc_queue, u->manager->user_gc_queue, u);
+        u->in_gc_queue = true;
+}
+
 UserState user_get_state(User *u) {
         Session *i;
 

src/logind-user.h

@@ -54,14 +54,18 @@ struct User {
 
         dual_timestamp timestamp;
 
+        bool in_gc_queue:1;
+
         LIST_HEAD(Session, sessions);
+        LIST_FIELDS(User, gc_queue);
 };
 
 User* user_new(Manager *m, uid_t uid, gid_t gid, const char *name);
 void user_free(User *u);
+int user_check_gc(User *u);
+void user_add_to_gc_queue(User *u);
 int user_start(User *u);
 int user_stop(User *u);
-int user_check_gc(User *u);
 UserState user_get_state(User *u);
 int user_save(User *u);
 int user_load(User *u);

src/logind.c

@@ -200,7 +200,6 @@ int manager_add_session(Manager *m, User *u, const char *id, Session **_session)
 
 int manager_add_user(Manager *m, uid_t uid, gid_t gid, const char *name, User **_user) {
         User *u;
-        int r;
 
         assert(m);
         assert(name);
@@ -217,16 +216,10 @@ int manager_add_user(Manager *m, uid_t uid, gid_t gid, const char *name, User **
         if (!u)
                 return -ENOMEM;
 
-        r = user_start(u);
+        if (_user)
-        if (r < 0) {
+                *_user = u;
-                user_stop(u);
-                user_free(u);
-        } else {
-                if (_user)
-                        *_user = u;
-        }
 
-        return r;
+        return 0;
 }
 
 int manager_add_user_by_name(Manager *m, const char *name, User **_user) {
@@ -257,33 +250,53 @@ int manager_add_user_by_uid(Manager *m, uid_t uid, User **_user) {
 }
 
 int manager_process_device(Manager *m, struct udev_device *d) {
-        const char *sn;
-        Seat *seat;
         Device *device;
         int r;
 
         assert(m);
 
-        sn = udev_device_get_property_value(d, "SEAT");
+        if (streq_ptr(udev_device_get_action(d), "remove")) {
-        if (!sn)
-                sn = "seat0";
 
-        r = manager_add_device(m, udev_device_get_syspath(d), &device);
+                device = hashmap_get(m->devices, udev_device_get_syspath(d));
-        if (r < 0)
+                if (!device)
-                return r;
+                        return 0;
 
-        r = manager_add_seat(m, sn, &seat);
+                seat_add_to_gc_queue(device->seat);
-        if (r < 0)
+                device_free(device);
-                return r;
+
+        } else {
+                const char *sn;
+                Seat *seat;
+
+                sn = udev_device_get_property_value(d, "SEAT");
+                if (!sn)
+                        sn = "seat0";
+
+                if (!startswith(sn, "seat"))
+                        return -EINVAL;
+
+                r = manager_add_device(m, udev_device_get_syspath(d), &device);
+                if (r < 0)
+                        return r;
+
+                r = manager_add_seat(m, sn, &seat);
+                if (r < 0) {
+                        if (!device->seat)
+                                device_free(device);
+
+                        return r;
+                }
+
+                device_attach(device, seat);
+        }
 
-        device_attach(device, seat);
         return 0;
 }
 
 int manager_enumerate_devices(Manager *m) {
         struct udev_list_entry *item = NULL, *first = NULL;
         struct udev_enumerate *e;
-        int r = -ENOMEM;
+        int r;
 
         assert(m);
 
@@ -291,16 +304,21 @@ int manager_enumerate_devices(Manager *m) {
          * necessary */
 
         e = udev_enumerate_new(m->udev);
-        if (!e)
+        if (!e) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        r = udev_enumerate_add_match_subsystem(e, "graphics");
+        if (r < 0)
                 goto finish;
 
-        if (udev_enumerate_add_match_subsystem(e, "graphics") < 0)
+        r = udev_enumerate_add_match_tag(e, "seat");
+        if (r < 0)
                 goto finish;
 
-        if (udev_enumerate_add_match_tag(e, "seat") < 0)
+        r = udev_enumerate_scan_devices(e);
-                goto finish;
+        if (r < 0)
-
-        if (udev_enumerate_scan_devices(e) < 0)
                 goto finish;
 
         first = udev_enumerate_get_list_entry(e);
@@ -309,8 +327,10 @@ int manager_enumerate_devices(Manager *m) {
                 int k;
 
                 d = udev_device_new_from_syspath(m->udev, udev_list_entry_get_name(item));
-                if (!d)
+                if (!d) {
+                        r = -ENOMEM;
                         goto finish;
+                }
 
                 k = manager_process_device(m, d);
                 udev_device_unref(d);
@@ -353,6 +373,9 @@ int manager_enumerate_seats(Manager *m) {
                 if (!dirent_is_file(de))
                         continue;
 
+                if (!startswith(de->d_name, "seat"))
+                        continue;
+
                 s = hashmap_get(m->seats, de->d_name);
                 if (!s) {
                         unlinkat(dirfd(d), de->d_name, 0);
@@ -385,24 +408,61 @@ static int manager_enumerate_users_from_cgroup(Manager *m) {
 
         while ((r = cg_read_subgroup(d, &name)) > 0) {
                 User *user;
+                int k;
+
+                k = manager_add_user_by_name(m, name, &user);
+                if (k < 0) {
+                        free(name);
+                        r = k;
+                        continue;
+                }
+
+                user_add_to_gc_queue(user);
+
+                if (!user->cgroup_path)
+                        if (asprintf(&user->cgroup_path, "%s/%s", m->cgroup_path, name) < 0) {
+                                r = -ENOMEM;
+                                free(name);
+                                break;
+                        }
 
-                r = manager_add_user_by_name(m, name, &user);
                 free(name);
+        }
 
-                if (r < 0)
+        closedir(d);
-                        break;
 
-                if (user->cgroup_path)
+        return r;
+}
+
+
+static int manager_enumerate_linger_users(Manager *m) {
+        DIR *d;
+        struct dirent *de;
+        int r = 0;
+
+        d = opendir("/var/lib/systemd/linger");
+        if (!d) {
+                if (errno == ENOENT)
+                        return 0;
+
+                log_error("Failed to open /var/lib/systemd/linger/: %m");
+                return -errno;
+        }
+
+        while ((de = readdir(d))) {
+                int k;
+
+                if (!dirent_is_file(de))
                         continue;
 
-                if (asprintf(&user->cgroup_path, "%s/%s", m->cgroup_path, name) < 0) {
+                k = manager_add_user_by_name(m, de->d_name, NULL);
-                        r = -ENOMEM;
+                if (k < 0) {
-                        break;
+                        log_notice("Couldn't add lingering user %s: %s", de->d_name, strerror(-k));
+                        r = k;
                 }
         }
 
-        if (d)
+        closedir(d);
-                closedir(d);
 
         return r;
 }
@@ -410,12 +470,19 @@ static int manager_enumerate_users_from_cgroup(Manager *m) {
 int manager_enumerate_users(Manager *m) {
         DIR *d;
         struct dirent *de;
-        int r;
+        int r, k;
 
         assert(m);
 
+        /* First, enumerate user cgroups */
         r = manager_enumerate_users_from_cgroup(m);
 
+        /* Second, add lingering users on top */
+        k = manager_enumerate_linger_users(m);
+        if (k < 0)
+                r = k;
+
+        /* Third, read in user data stored on disk */
         d = opendir("/run/systemd/users");
         if (!d) {
                 if (errno == ENOENT)
@@ -428,7 +495,6 @@ int manager_enumerate_users(Manager *m) {
         while ((de = readdir(d))) {
                 unsigned long ul;
                 User *u;
-                int k;
 
                 if (!dirent_is_file(de))
                         continue;
@@ -465,6 +531,9 @@ static int manager_enumerate_sessions_from_cgroup(Manager *m) {
                 char *name;
                 int k;
 
+                if (!u->cgroup_path)
+                        continue;
+
                 k = cg_enumerate_subgroups(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, &d);
                 if (k < 0) {
                         if (k == -ENOENT)
@@ -479,18 +548,21 @@ static int manager_enumerate_sessions_from_cgroup(Manager *m) {
                         Session *session;
 
                         k = manager_add_session(m, u, name, &session);
-                        free(name);
+                        if (k < 0) {
-
+                                free(name);
-                        if (k < 0)
-                                break;
-
-                        if (session->cgroup_path)
-                                continue;
-
-                        if (asprintf(&session->cgroup_path, "%s/%s", u->cgroup_path, name) < 0) {
-                                k = -ENOMEM;
                                 break;
                         }
+
+                        session_add_to_gc_queue(session);
+
+                        if (!session->cgroup_path)
+                                if (asprintf(&session->cgroup_path, "%s/%s", u->cgroup_path, name) < 0) {
+                                        k = -ENOMEM;
+                                        free(name);
+                                        break;
+                                }
+
+                        free(name);
                 }
 
                 closedir(d);
@@ -509,8 +581,10 @@ int manager_enumerate_sessions(Manager *m) {
 
         assert(m);
 
+        /* First enumerate session cgroups */
         r = manager_enumerate_sessions_from_cgroup(m);
 
+        /* Second, read in session data stored on disk */
         d = opendir("/run/systemd/sessions");
         if (!d) {
                 if (errno == ENOENT)
@@ -543,38 +617,6 @@ int manager_enumerate_sessions(Manager *m) {
         return r;
 }
 
-int manager_start_linger_users(Manager *m) {
-        DIR *d;
-        struct dirent *de;
-        int r = 0;
-
-        d = opendir("/var/lib/systemd/linger");
-        if (!d) {
-                if (errno == ENOENT)
-                        return 0;
-
-                log_error("Failed to open /var/lib/systemd/linger/: %m");
-                return -errno;
-        }
-
-        while ((de = readdir(d))) {
-                int k;
-
-                if (!dirent_is_file(de))
-                        continue;
-
-                k = manager_add_user_by_name(m, de->d_name, NULL);
-                if (k < 0) {
-                        log_notice("Couldn't add lingering user %s: %s", de->d_name, strerror(-k));
-                        r = k;
-                }
-        }
-
-        closedir(d);
-
-        return r;
-}
-
 int manager_dispatch_udev(Manager *m) {
         struct udev_device *d;
         int r;
@@ -592,39 +634,10 @@ int manager_dispatch_udev(Manager *m) {
 }
 
 int manager_dispatch_console(Manager *m) {
-        char t[64];
-        ssize_t k;
-        int r, vtnr;
-
         assert(m);
 
-        lseek(m->console_active_fd, SEEK_SET, 0);
-
-        k = read(m->console_active_fd, t, sizeof(t)-1);
-        if (k <= 0) {
-                log_error("Failed to read current console: %s", k < 0 ? strerror(-errno) : "EOF");
-                return k < 0 ? -errno : -EIO;
-        }
-
-        t[k] = 0;
-        if (!startswith(t, "tty")) {
-                log_error("Hm, /sys/class/tty/tty0/active is badly formatted.");
-                return -EIO;
-        }
-
-        r = safe_atoi(t+3, &vtnr);
-        if (r < 0) {
-                log_error("Failed to parse VT number %s", t+3);
-                return r;
-        }
-
-        if (vtnr <= 0) {
-                log_error("VT number invalid: %s", t+3);
-                return -EIO;
-        }
-
         if (m->vtconsole)
-                seat_active_vt_changed(m->vtconsole, vtnr);
+                seat_read_active_vt(m->vtconsole);
 
         return 0;
 }
@@ -766,7 +779,7 @@ static int manager_connect_console(Manager *m) {
         }
 
         zero(ev);
-        ev.events = EPOLLIN;
+        ev.events = 0;
         ev.data.u32 = FD_CONSOLE;
 
         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->console_active_fd, &ev) < 0)
@@ -777,6 +790,7 @@ static int manager_connect_console(Manager *m) {
 
 static int manager_connect_udev(Manager *m) {
         struct epoll_event ev;
+        int r;
 
         assert(m);
         assert(!m->udev_monitor);
@@ -785,13 +799,17 @@ static int manager_connect_udev(Manager *m) {
         if (!m->udev_monitor)
                 return -ENOMEM;
 
-        udev_monitor_filter_add_match_tag(m->udev_monitor, "seat");
+        r = udev_monitor_filter_add_match_tag(m->udev_monitor, "seat");
+        if (r < 0)
+                return r;
 
-        if (udev_monitor_filter_add_match_subsystem_devtype(m->udev_monitor, "graphics", NULL) < 0)
+        r = udev_monitor_filter_add_match_subsystem_devtype(m->udev_monitor, "graphics", NULL);
-                return -ENOMEM;
+        if (r < 0)
+                return r;
 
-        if (udev_monitor_enable_receiving(m->udev_monitor) < 0)
+        r = udev_monitor_enable_receiving(m->udev_monitor);
-                return -ENOMEM;
+        if (r < 0)
+                return r;
 
         m->udev_fd = udev_monitor_get_fd(m->udev_monitor);
 
@@ -805,8 +823,50 @@ static int manager_connect_udev(Manager *m) {
         return 0;
 }
 
+void manager_gc(Manager *m) {
+        Seat *seat;
+        Session *session;
+        User *user;
+
+        assert(m);
+
+        while ((seat = m->seat_gc_queue)) {
+                LIST_REMOVE(Seat, gc_queue, m->seat_gc_queue, seat);
+                seat->in_gc_queue = false;
+
+                if (seat_check_gc(seat) == 0) {
+                        seat_stop(seat);
+                        seat_free(seat);
+                }
+        }
+
+        while ((session = m->session_gc_queue)) {
+                LIST_REMOVE(Session, gc_queue, m->session_gc_queue, session);
+                session->in_gc_queue = false;
+
+                if (session_check_gc(session) == 0) {
+                        session_stop(session);
+                        session_free(session);
+                }
+        }
+
+        while ((user = m->user_gc_queue)) {
+                LIST_REMOVE(User, gc_queue, m->user_gc_queue, user);
+                user->in_gc_queue = false;
+
+                if (user_check_gc(user) == 0) {
+                        user_stop(user);
+                        user_free(user);
+                }
+        }
+}
+
 int manager_startup(Manager *m) {
         int r;
+        Seat *seat;
+        Session *session;
+        User *user;
+        Iterator i;
 
         assert(m);
         assert(m->epoll_fd <= 0);
@@ -830,14 +890,29 @@ int manager_startup(Manager *m) {
         if (r < 0)
                 return r;
 
+        /* Instantiate magic seat 0 */
+        r = manager_add_seat(m, "seat0", &m->vtconsole);
+        if (r < 0)
+                return r;
+
         /* Deserialize state */
         manager_enumerate_devices(m);
         manager_enumerate_seats(m);
         manager_enumerate_users(m);
         manager_enumerate_sessions(m);
 
-        /* Spawn lingering users */
+        /* Get rid of objects that are no longer used */
-        manager_start_linger_users(m);
+        manager_gc(m);
+
+        /* And start everything */
+        HASHMAP_FOREACH(seat, m->seats, i)
+                seat_start(seat);
+
+        HASHMAP_FOREACH(user, m->users, i)
+                user_start(user);
+
+        HASHMAP_FOREACH(session, m->sessions, i)
+                session_start(session);
 
         return 0;
 }
@@ -849,6 +924,8 @@ int manager_run(Manager *m) {
                 struct epoll_event event;
                 int n;
 
+                manager_gc(m);
+
                 if (dbus_connection_dispatch(m->bus) != DBUS_DISPATCH_COMPLETE)
                         continue;
 

src/logind.h

@@ -59,6 +59,10 @@ struct Manager {
         Hashmap *sessions;
         Hashmap *users;
 
+        LIST_HEAD(Seat, seat_gc_queue);
+        LIST_HEAD(Session, session_gc_queue);
+        LIST_HEAD(User, user_gc_queue);
+
         struct udev *udev;
         struct udev_monitor *udev_monitor;
 
@@ -81,25 +85,29 @@ struct Manager {
 
 Manager *manager_new(void);
 void manager_free(Manager *m);
+
 int manager_add_device(Manager *m, const char *sysfs, Device **_device);
 int manager_add_seat(Manager *m, const char *id, Seat **_seat);
 int manager_add_session(Manager *m, User *u, const char *id, Session **_session);
 int manager_add_user(Manager *m, uid_t uid, gid_t gid, const char *name, User **_user);
 int manager_add_user_by_name(Manager *m, const char *name, User **_user);
 int manager_add_user_by_uid(Manager *m, uid_t uid, User **_user);
+
 int manager_process_device(Manager *m, struct udev_device *d);
 int manager_dispatch_udev(Manager *m);
 int manager_dispatch_console(Manager *m);
+
 int manager_enumerate_devices(Manager *m);
 int manager_enumerate_seats(Manager *m);
 int manager_enumerate_sessions(Manager *m);
 int manager_enumerate_users(Manager *m);
-int manager_start_one_linger_user(Manager *m, const char *user);
+
-int manager_start_linger_users(Manager *m);
 int manager_startup(Manager *m);
 int manager_run(Manager *m);
 int manager_spawn_autovt(Manager *m, int vtnr);
 
+void manager_gc(Manager *m);
+
 bool x11_display_is_local(const char *display);
 
 #endif

src/org.freedesktop.login1.conf

@@ -0,0 +1,28 @@
+<?xml version="1.0"?> <!--*-nxml-*-->
+<!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"
+        "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
+
+<!--
+  This file is part of systemd.
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+-->
+
+<busconfig>
+
+        <policy user="root">
+                <allow own="org.freedesktop.login1"/>
+                <allow send_destination="org.freedesktop.login1"/>
+                <allow receive_sender="org.freedesktop.login1"/>
+        </policy>
+
+        <policy context="default">
+                <allow own="org.freedesktop.login1"/>
+                <allow send_destination="org.freedesktop.login1"/>
+                <allow receive_sender="org.freedesktop.login1"/>
+        </policy>
+
+</busconfig>