use spinlocks and other fixes

source/qjs_actor.c

@@ -166,16 +166,9 @@ JSC_CCALL(actor_on_exception,
 JSC_CCALL(actor_clock,
   if (!JS_IsFunction(js, argv[0]))
     return JS_ThrowReferenceError(js, "Argument must be a function.");
-
+    
   cell_rt *actor = JS_GetContextOpaque(js);
-  SDL_LockMutex(actor->msg_mutex);
-  letter l;
-  l.type = LETTER_CALLBACK;
-  l.callback = JS_DupValue(js, argv[0]);
-  arrput(actor->letters, l);
-  SDL_UnlockMutex(actor->msg_mutex);
-  printf("actor %s clocked\n", actor->id);
-  set_actor_state(actor);
+  actor_clock(actor, argv[0]);
 )
 
 static const JSCFunctionListEntry js_actor_funcs[] = {