/* -*- 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_ipc_backgroundparent_h__

#define mozilla_ipc_backgroundparent_h__

#include "base/process.h"

#include "mozilla/Attributes.h"

#include "mozilla/ipc/Transport.h"

template <class> struct already_AddRefed;

namespace mozilla {

namespace dom {

class BlobImpl;

class ContentParent;

} // namespace dom

namespace ipc {

class PBackgroundParent;

template<class PFooSide> class Endpoint;

// This class is not designed for public consumption beyond the few static

// member functions.

class BackgroundParent final

{

  friend class mozilla::dom::ContentParent;

  typedef base::ProcessId ProcessId;

  typedef mozilla::dom::BlobImpl BlobImpl;

  typedef mozilla::dom::ContentParent ContentParent;

  typedef mozilla::ipc::Transport Transport;

public:

  // This function allows the caller to determine if the given parent actor

  // corresponds to a child actor from another process or a child actor from a

  // different thread in the same process.

  // This function may only be called on the background thread.

  static bool

  IsOtherProcessActor(PBackgroundParent* aBackgroundActor);

  // This function returns the ContentParent associated with the parent actor if

  // the parent actor corresponds to a child actor from another process. If the

  // parent actor corresponds to a child actor from a different thread in the

  // same process then this function returns null.

  // This function may only be called on the background thread. However,

  // ContentParent is not threadsafe and the returned pointer may not be used on

  // any thread other than the main thread. Callers must take care to use (and

  // release) the returned pointer appropriately.

  static already_AddRefed<ContentParent>

  GetContentParent(PBackgroundParent* aBackgroundActor);

  // Get a value that represents the ContentParent associated with the parent

  // actor for comparison. The value is not guaranteed to uniquely identify the

  // ContentParent after the ContentParent has died. This function may only be

  // called on the background thread.

  static intptr_t

  GetRawContentParentForComparison(PBackgroundParent* aBackgroundActor);

  static uint64_t

  GetChildID(PBackgroundParent* aBackgroundActor);

  static bool

  GetLiveActorArray(PBackgroundParent* aBackgroundActor,

                    nsTArray<PBackgroundParent*>& aLiveActorArray);

private:

  // Only called by ContentParent for cross-process actors.

  static bool

  Alloc(ContentParent* aContent,

        Endpoint<PBackgroundParent>&& aEndpoint);

};

// Implemented in BackgroundImpl.cpp.

bool

IsOnBackgroundThread();

#ifdef DEBUG

// Implemented in BackgroundImpl.cpp.

void

AssertIsOnBackgroundThread();

#else

inline void

AssertIsOnBackgroundThread()

{ }

#endif // DEBUG

inline void

AssertIsInMainProcess()

{

  MOZ_ASSERT(XRE_IsParentProcess());

}

} // namespace ipc

} // namespace mozilla

#endif // mozilla_ipc_backgroundparent_h__