window: Don't call drag_offer_handler if it's NULL

Reported by canbaby@21cn.com.

diff --git a/clients/window.c b/clients/window.c
index 3abc2b0..9ed96be 100644 (file)
--- a/clients/window.c
+++ b/clients/window.c
@@ -1330,8 +1330,10 @@ display_handle_global(struct wl_display *display, uint32_t id,
        } else if (strcmp(interface, "shm") == 0) {
                d->shm = wl_shm_create(display, id);
        } else if (strcmp(interface, "drag_offer") == 0) {
-               offer = wl_drag_offer_create(display, id);
-               d->drag_offer_handler(offer, d);
+               if (d->drag_offer_handler) {
+                       offer = wl_drag_offer_create(display, id);
+                       d->drag_offer_handler(offer, d);
+               }
        }
 }