/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef MOZILLA_LAYERS_IPDLACTOR_H

#define MOZILLA_LAYERS_IPDLACTOR_H

#include "mozilla/ipc/ProtocolUtils.h"

#include "mozilla/layers/CompositableForwarder.h"

#include "mozilla/Unused.h"

#include "gfxPlatform.h"

namespace mozilla {

namespace layers {

/// A base class to facilitate the deallocation of IPDL actors.

///

/// Implements the parent side of the simple deallocation handshake.

/// Override the Destroy method rather than the ActorDestroy method.

template<typename Protocol>

class ParentActor : public Protocol

{

public:

  ParentActor() : mDestroyed(false) {}

  ~ParentActor() { MOZ_ASSERT(mDestroyed); }

  bool CanSend() const { return !mDestroyed; }

  // Override this rather than ActorDestroy

  virtual void Destroy() {}

  virtual mozilla::ipc::IPCResult RecvDestroy() override

  {

    DestroyIfNeeded();

    Unused << Protocol::Send__delete__(this);

    return IPC_OK();

  }

  typedef ipc::IProtocol::ActorDestroyReason Why;

  virtual void ActorDestroy(Why) override {

    DestroyIfNeeded();

  }

protected:

  void DestroyIfNeeded() {

    if (!mDestroyed) {

      Destroy();

      mDestroyed = true;

    }

  }

private:

  bool mDestroyed;

};

} // namespace

} // namespace

#endif