/* -*- 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/. */

#include <windows.h>

#include "base/process_util.h"

#include "CrossProcessSemaphore.h"

#include "nsDebug.h"

#include "nsISupportsImpl.h"

#include "ProtocolUtils.h"

using base::GetCurrentProcessHandle;

using base::ProcessHandle;

namespace mozilla {

/* static */ CrossProcessSemaphore* CrossProcessSemaphore::Create(

    const char*, uint32_t aInitialValue) {

  // We explicitly share this using DuplicateHandle, we do -not- want this to

  // be inherited by child processes by default! So no security attributes are

  // given.

  HANDLE semaphore =

      ::CreateSemaphoreA(nullptr, aInitialValue, 0x7fffffff, nullptr);

  if (!semaphore) {

    return nullptr;

  }

  return new CrossProcessSemaphore(semaphore);

}

/* static */ CrossProcessSemaphore* CrossProcessSemaphore::Create(

    CrossProcessSemaphoreHandle aHandle) {

  DWORD flags;

  if (!::GetHandleInformation(aHandle, &flags)) {

    return nullptr;

  }

  return new CrossProcessSemaphore(aHandle);

}

CrossProcessSemaphore::CrossProcessSemaphore(HANDLE aSemaphore)

    : mSemaphore(aSemaphore) {

  MOZ_COUNT_CTOR(CrossProcessSemaphore);

}

CrossProcessSemaphore::~CrossProcessSemaphore() {

  MOZ_ASSERT(mSemaphore, "Improper construction of semaphore or double free.");

  ::CloseHandle(mSemaphore);

  MOZ_COUNT_DTOR(CrossProcessSemaphore);

}

bool CrossProcessSemaphore::Wait(const Maybe<TimeDuration>& aWaitTime) {

  MOZ_ASSERT(mSemaphore, "Improper construction of semaphore.");

  HRESULT hr = ::WaitForSingleObject(

      mSemaphore, aWaitTime.isSome() ? aWaitTime->ToMilliseconds() : INFINITE);

  return hr == WAIT_OBJECT_0;

}

void CrossProcessSemaphore::Signal() {

  MOZ_ASSERT(mSemaphore, "Improper construction of semaphore.");

  ::ReleaseSemaphore(mSemaphore, 1, nullptr);

}

CrossProcessSemaphoreHandle CrossProcessSemaphore::ShareToProcess(

    base::ProcessId aTargetPid) {

  HANDLE newHandle;

  bool succeeded = ipc::DuplicateHandle(mSemaphore, aTargetPid, &newHandle, 0,

                                        DUPLICATE_SAME_ACCESS);

  if (!succeeded) {

    return nullptr;

  }

  return newHandle;

}

void CrossProcessSemaphore::CloseHandle() {}

}  // namespace mozilla