virsystemd: Don't fail to start VM if DBus isn't available or compiled in

On hosts that don't have the DBus service running or installed the new
systemd cgroups code failed with hard error instead of falling back to
"manual" cgroup creation.

Use the new helper to check for the system bus and use the fallback code
in case it isn't available.

diff --git a/src/util/virsystemd.c b/src/util/virsystemd.c
index 251b8463ffd5d4a0e7e00df4a1c08ff1ee4fc527..3e69ef66790fd8de00e80f67556645463e3d6975 100644 (file)
--- a/src/util/virsystemd.c
+++ b/src/util/virsystemd.c
@@ -145,8 +145,10 @@ int virSystemdCreateMachine(const char *name,
     char *username = NULL;
     char *slicename = NULL;
 
-    if (!(conn = virDBusGetSystemBus()))
-        return -1;
+    if (!virDBusHasSystemBus())
+        return -2;
+
+    conn = virDBusGetSystemBus();
 
     if (privileged) {
         if (virAsprintf(&machinename, "%s-%s", drivername, name) < 0)