|  | // Copyright 2013 The Chromium Authors. All rights reserved. | 
|  | // Use of this source code is governed by a BSD-style license that can be | 
|  | // found in the LICENSE file. | 
|  |  | 
|  | #include "gin/function_template.h" | 
|  |  | 
|  | namespace gin { | 
|  |  | 
|  | namespace internal { | 
|  |  | 
|  | CallbackHolderBase::CallbackHolderBase(v8::Isolate* isolate) | 
|  | : v8_ref_(isolate, v8::External::New(isolate, this)) { | 
|  | v8_ref_.SetWeak(this, &CallbackHolderBase::FirstWeakCallback, | 
|  | v8::WeakCallbackType::kParameter); | 
|  | } | 
|  |  | 
|  | CallbackHolderBase::~CallbackHolderBase() { | 
|  | DCHECK(v8_ref_.IsEmpty()); | 
|  | } | 
|  |  | 
|  | v8::Local<v8::External> CallbackHolderBase::GetHandle(v8::Isolate* isolate) { | 
|  | return v8::Local<v8::External>::New(isolate, v8_ref_); | 
|  | } | 
|  |  | 
|  | // static | 
|  | void CallbackHolderBase::FirstWeakCallback( | 
|  | const v8::WeakCallbackInfo<CallbackHolderBase>& data) { | 
|  | data.GetParameter()->v8_ref_.Reset(); | 
|  | data.SetSecondPassCallback(SecondWeakCallback); | 
|  | } | 
|  |  | 
|  | // static | 
|  | void CallbackHolderBase::SecondWeakCallback( | 
|  | const v8::WeakCallbackInfo<CallbackHolderBase>& data) { | 
|  | delete data.GetParameter(); | 
|  | } | 
|  |  | 
|  | }  // namespace internal | 
|  |  | 
|  | }  // namespace gin |