diff --git a/src/system-update-generator/system-update-generator.c b/src/system-update-generator/system-update-generator.c
index 80f53cf34c..77e265d710 100644
--- a/src/system-update-generator/system-update-generator.c
+++ b/src/system-update-generator/system-update-generator.c
@@ -15,7 +15,7 @@
  * Implements the logic described in systemd.offline-updates(7).
  */
 
-static const char *arg_dest = "/tmp";
+static const char *arg_dest = NULL;
 
 static int generate_symlink(void) {
         const char *p = NULL;
@@ -51,26 +51,20 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
         return 0;
 }
 
-int main(int argc, char *argv[]) {
-        int r, k;
+static int run(const char *dest, const char *dest_early, const char *dest_late) {
+        int r;
 
-        log_setup_generator();
-
-        if (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return EXIT_FAILURE;
-        }
-
-        if (argc > 1)
-                arg_dest = argv[2];
+        assert_se(arg_dest = dest_early);
 
         r = generate_symlink();
+        if (r < 0)
+                return r;
 
-        if (r > 0) {
-                k = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
-                if (k < 0)
-                        log_warning_errno(k, "Failed to parse kernel command line, ignoring: %m");
-        }
+        r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
+        if (r < 0)
+                log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 
-        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+        return 0;
 }
+
+DEFINE_MAIN_GENERATOR_FUNCTION(run);