terminal-util: also protect from empty /sys/class/tty/tty0/active

(cherry picked from commit 48c1393bfb026e114aed56f1c2b8564662039c9b)
(cherry picked from commit 279c0be61c0ac6e4708416fb397d4b22ca084c1e)
(cherry picked from commit 06271db1805c1de913fce9f7a33241de86c47af9)

diff --git a/src/basic/terminal-util.c b/src/basic/terminal-util.c
index 02df893b1965ec7ef9cb4a674e297607399169ab..de039226b0471a69afdbd055c9af8a4a42a00578 100644 (file)
--- a/src/basic/terminal-util.c
+++ b/src/basic/terminal-util.c
@@ -816,6 +816,8 @@ int resolve_dev_console(char **ret) {
                 r = read_one_line_file("/sys/class/tty/tty0/active", &active);
                 if (r < 0)
                         return r;
+                if (r == 0)
+                        return -ENXIO;
 
                 tty = active;
         }
@@ -859,6 +861,10 @@ int get_kernel_consoles(char ***ret) {
                         r = read_one_line_file("/sys/class/tty/tty0/active", &tty);
                         if (r < 0)
                                 return r;
+                        if (r == 0) {
+                                log_debug("No VT active, skipping /dev/tty0.");
+                                continue;
+                        }
                 }
 
                 path = path_join("/dev", tty);