+void session_prepare_vt(Session *s) {
+ int vt, r;
+ struct vt_mode mode = { 0 };
+ sigset_t mask;
+
+ vt = session_open_vt(s);
+ if (vt < 0)
+ return;
+
+ r = fchown(vt, s->user->uid, -1);
+ if (r < 0)
+ goto error;
+
+ r = ioctl(vt, KDSKBMODE, K_OFF);
+ if (r < 0)
+ goto error;
+
+ r = ioctl(vt, KDSETMODE, KD_GRAPHICS);
+ if (r < 0)
+ goto error;
+
+ sigemptyset(&mask);
+ sigaddset(&mask, SIGUSR1);
+ sigprocmask(SIG_BLOCK, &mask, NULL);
+
+ r = sd_event_add_signal(s->manager->event, &s->vt_source, SIGUSR1, session_vt_fn, s);
+ if (r < 0)
+ goto error;
+
+ /* Oh, thanks to the VT layer, VT_AUTO does not work with KD_GRAPHICS.
+ * So we need a dummy handler here which just acknowledges *all* VT
+ * switch requests. */
+ mode.mode = VT_PROCESS;
+ mode.relsig = SIGUSR1;
+ mode.acqsig = SIGUSR1;
+ r = ioctl(vt, VT_SETMODE, &mode);
+ if (r < 0)
+ goto error;
+
+ return;
+
+error:
+ log_error("cannot mute VT %u for session %s (%d/%d)", s->vtnr, s->id, r, errno);
+ session_restore_vt(s);
+}
+
+void session_restore_vt(Session *s) {
+ _cleanup_free_ char *utf8 = NULL;
+ int vt, kb = K_XLATE;
+ struct vt_mode mode = { 0 };
+
+ vt = session_open_vt(s);
+ if (vt < 0)
+ return;
+
+ s->vt_source = sd_event_source_unref(s->vt_source);
+
+ ioctl(vt, KDSETMODE, KD_TEXT);
+
+ if (read_one_line_file("/sys/module/vt/parameters/default_utf8", &utf8) >= 0 && *utf8 == '1')
+ kb = K_UNICODE;
+
+ ioctl(vt, KDSKBMODE, kb);
+
+ mode.mode = VT_AUTO;
+ ioctl(vt, VT_SETMODE, &mode);
+
+ fchown(vt, 0, -1);
+
+ s->vtfd = safe_close(s->vtfd);
+}
+
+bool session_is_controller(Session *s, const char *sender) {
+ assert(s);
+
+ return streq_ptr(s->controller, sender);
+}
+
+static void session_swap_controller(Session *s, char *name) {
+ SessionDevice *sd;
+
+ if (s->controller) {
+ manager_drop_busname(s->manager, s->controller);
+ free(s->controller);
+ s->controller = NULL;
+
+ /* Drop all devices as they're now unused. Do that after the
+ * controller is released to avoid sending out useles
+ * dbus signals. */
+ while ((sd = hashmap_first(s->devices)))
+ session_device_free(sd);
+
+ if (!name)
+ session_restore_vt(s);