+static int callback(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
+ return 1;
+}
+
+static void destroy_callback(void *userdata) {
+ int *n_called = userdata;
+
+ (*n_called) ++;
+}
+
+static void test_destroy_callback(void) {
+ _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
+ sd_bus_slot *slot = NULL;
+ sd_bus_destroy_t t;
+
+ int r, n_called = 0;
+
+ log_info("/* %s */", __func__);
+
+ r = bus_open_system_watch_bind_with_description(&bus, "test-bus");
+ if (r < 0) {
+ log_error_errno(r, "Failed to connect to bus: %m");
+ return;
+ }
+
+ r = sd_bus_request_name_async(bus, &slot, "org.freedesktop.elogind.test-bus-util", 0, callback, &n_called);
+ assert(r == 1);
+
+ assert_se(sd_bus_slot_get_destroy_callback(slot, NULL) == 0);
+ assert_se(sd_bus_slot_get_destroy_callback(slot, &t) == 0);
+
+ assert_se(sd_bus_slot_set_destroy_callback(slot, destroy_callback) == 0);
+ assert_se(sd_bus_slot_get_destroy_callback(slot, NULL) == 1);
+ assert_se(sd_bus_slot_get_destroy_callback(slot, &t) == 1);
+ assert_se(t == destroy_callback);
+
+ /* Force cleanup so we can look at n_called */
+ assert(n_called == 0);
+ sd_bus_slot_unref(slot);
+ assert(n_called == 1);
+}
+