third_party/WebKit/Source/platform/bindings/ScriptState.cpp

// Copyright 2014 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 "platform/bindings/ScriptState.h"

#include "platform/bindings/V8Binding.h"

namespace blink {

RefPtr<ScriptState> ScriptState::Create(v8::Local<v8::Context> context,
                                        RefPtr<DOMWrapperWorld> world) {
  RefPtr<ScriptState> script_state =
      WTF::AdoptRef(new ScriptState(context, std::move(world)));
  // This ref() is for keeping this ScriptState alive as long as the v8::Context
  // is alive.  This is deref()ed in the weak callback of the v8::Context.
  script_state->Ref();
  return script_state;
}

static void DerefCallback(const v8::WeakCallbackInfo<ScriptState>& data) {
  data.GetParameter()->Deref();
}

static void ContextCollectedCallback(
    const v8::WeakCallbackInfo<ScriptState>& data) {
  data.GetParameter()->ClearContext();
  data.SetSecondPassCallback(DerefCallback);
}

ScriptState::ScriptState(v8::Local<v8::Context> context,
                         RefPtr<DOMWrapperWorld> world)
    : isolate_(context->GetIsolate()),
      context_(isolate_, context),
      world_(std::move(world)),
      per_context_data_(V8PerContextData::Create(context)) {
  DCHECK(world_);
  context_.SetWeak(this, &ContextCollectedCallback);
  context->SetAlignedPointerInEmbedderData(kV8ContextPerContextDataIndex, this);
}

ScriptState::~ScriptState() {
  DCHECK(!per_context_data_);
  DCHECK(context_.IsEmpty());
}

void ScriptState::DetachGlobalObject() {
  DCHECK(!context_.IsEmpty());
  GetContext()->DetachGlobal();
}

void ScriptState::DisposePerContextData() {
  per_context_data_ = nullptr;
}

}  // namespace blink