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

/* 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 "mozilla/widget/nsAutoRollup.h"

namespace mozilla {

namespace widget {

/*static*/ uint32_t nsAutoRollup::sCount = 0;

/*static*/ StaticRefPtr<nsIContent> nsAutoRollup::sLastRollup;

nsAutoRollup::nsAutoRollup() {

  // remember if sLastRollup was null, and only clear it upon destruction

  // if so. This prevents recursive usage of nsAutoRollup from clearing

  // sLastRollup when it shouldn't.

  mWasClear = !sLastRollup;

  sCount++;

}

nsAutoRollup::nsAutoRollup(nsIContent* aRollup) {

  MOZ_ASSERT(!sLastRollup);

  mWasClear = true;

  sCount++;

  SetLastRollup(aRollup);

}

nsAutoRollup::~nsAutoRollup() {

  if (sLastRollup && mWasClear) {

    sLastRollup = nullptr;

  }

  sCount--;

}

/*static*/ void nsAutoRollup::SetLastRollup(nsIContent* aLastRollup) {

  // There must be at least one nsAutoRollup on the stack.

  MOZ_ASSERT(sCount);

  sLastRollup = aLastRollup;

}

/*static*/ nsIContent* nsAutoRollup::GetLastRollup() {

  return sLastRollup.get();

}

}  // namespace widget

}  // namespace mozilla