core: require $XDG_RUNTIME_DIR to be set for user instances

It seems that some places use /run otherwise, which isn't going to work.

diff --git a/src/core/main.c b/src/core/main.c
index b62234ed451bbe42276e5c69b2e020b73240f821..d161968bb39125c690f576af5c99dd69c7dbb6c6 100644 (file)
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -1383,6 +1383,12 @@ int main(int argc, char *argv[]) {
                 goto finish;
         }
 
+        if (arg_running_as == SYSTEMD_USER &&
+            !getenv("XDG_RUNTIME_DIR")) {
+                log_error("Trying to run as user instance, but \$XDG_RUNTIME_DIR is not set.");
+                goto finish;
+        }
+
         if (arg_running_as == SYSTEMD_SYSTEM &&
             arg_action == ACTION_RUN &&
             running_in_chroot() > 0) {