From a77803467601cebc60ecc1c56105960a1aeb1a50 Mon Sep 17 00:00:00 2001
From: Ray Strode <rstrode@redhat.com>
Date: Fri, 31 Aug 2018 15:20:39 -0400
Subject: [PATCH 18/48] session-worker: fix current vt detection short-circuit
 logic

commit 8169cd4 attempts to avoid changing VTs if the active VT
is the same as the VT getting jumped to.

It fails to work, however, because accidentally treats a 0 return
code to the VT_GETSTATE ioctl as failure.

this commit fixes that.
---
 daemon/gdm-session-worker.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/daemon/gdm-session-worker.c b/daemon/gdm-session-worker.c
index fd6470bab..391969d96 100644
--- a/daemon/gdm-session-worker.c
+++ b/daemon/gdm-session-worker.c
@@ -963,61 +963,61 @@ jump_to_vt (GdmSessionWorker  *worker,
 {
         int fd;
         int active_vt_tty_fd;
         int active_vt = -1;
         struct vt_stat vt_state = { 0 };
 
         g_debug ("GdmSessionWorker: jumping to VT %d", vt_number);
         active_vt_tty_fd = open ("/dev/tty0", O_RDWR | O_NOCTTY);
 
         if (worker->priv->session_tty_fd != -1) {
                 fd = worker->priv->session_tty_fd;
 
                 g_debug ("GdmSessionWorker: first setting graphics mode to prevent flicker");
                 if (ioctl (fd, KDSETMODE, KD_GRAPHICS) < 0) {
                         g_debug ("GdmSessionWorker: couldn't set graphics mode: %m");
                 }
 
                 /* It's possible that the current VT was left in a broken
                  * combination of states (KD_GRAPHICS with VT_AUTO), that
                  * can't be switched away from.  This call makes sure things
                  * are set in a way that VT_ACTIVATE should work and
                  * VT_WAITACTIVE shouldn't hang.
                  */
                 fix_terminal_vt_mode (worker, active_vt_tty_fd);
         } else {
                 fd = active_vt_tty_fd;
         }
 
         handle_terminal_vt_switches (worker, fd);
 
-        if (ioctl (fd, VT_GETSTATE, &vt_state) <= 0) {
+        if (ioctl (fd, VT_GETSTATE, &vt_state) < 0) {
                 g_debug ("GdmSessionWorker: couldn't get current VT: %m");
         } else {
                 active_vt = vt_state.v_active;
         }
 
         if (active_vt != vt_number) {
                 if (ioctl (fd, VT_ACTIVATE, vt_number) < 0) {
                         g_debug ("GdmSessionWorker: couldn't initiate jump to VT %d: %m",
                                  vt_number);
                 } else if (ioctl (fd, VT_WAITACTIVE, vt_number) < 0) {
                         g_debug ("GdmSessionWorker: couldn't finalize jump to VT %d: %m",
                                  vt_number);
                 }
         }
 
         close (active_vt_tty_fd);
 }
 
 static void
 gdm_session_worker_set_state (GdmSessionWorker      *worker,
                               GdmSessionWorkerState  state)
 {
         if (worker->priv->state == state)
                 return;
 
         worker->priv->state = state;
         g_object_notify (G_OBJECT (worker), "state");
 }
 
 static void
-- 
2.26.0