dom/bindings/CallbackInterface.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/dom/CallbackInterface.h"
   8 #include "jsapi.h"
   9 #include "js/CallAndConstruct.h"  // JS::IsCallable
  10 #include "js/CharacterEncoding.h"
  11 #include "js/PropertyAndElement.h"  // JS_GetProperty, JS_GetPropertyById
  12 #include "mozilla/dom/BindingUtils.h"
  13 #include "nsPrintfCString.h"
  14
  15 namespace mozilla::dom {
  16
  17 bool CallbackInterface::GetCallableProperty(
  18     BindingCallContext& cx, JS::Handle<jsid> aPropId,
  19     JS::MutableHandle<JS::Value> aCallable) {
  20   JS::Rooted<JSObject*> obj(cx, CallbackKnownNotGray());
  21   if (!JS_GetPropertyById(cx, obj, aPropId, aCallable)) {
  22     return false;
  23   }
  24   if (!aCallable.isObject() || !JS::IsCallable(&aCallable.toObject())) {
  25     JS::Rooted<JSString*> propId(cx, aPropId.toString());
  26     JS::UniqueChars propName = JS_EncodeStringToUTF8(cx, propId);
  27     nsPrintfCString description("Property '%s'", propName.get());
  28     cx.ThrowErrorMessage<MSG_NOT_CALLABLE>(description.get());
  29     return false;
  30   }
  31
  32   return true;
  33 }
  34
  35 }  // namespace mozilla::dom