editor/txmgr/TransactionStack.h
author Nicolas Silva <nsilva@mozilla.com>
Thu, 14 Feb 2019 13:40:51 +0000
changeset 459125 e23608ddeac0b5e92b728965031796ded09dc8f2
parent 448947 6f3709b3878117466168c40affa7bca0b60cf75b
child 518013 22be6018155b9ab81ea4e29288d6d5a7a32b21cf
permissions -rw-r--r--
Bug 1527884 - WebRender version 0.60.0. r=emilio Differential Revision: https://phabricator.services.mozilla.com/D19780

/* -*- 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/. */

#ifndef mozilla_TransactionStack_h
#define mozilla_TransactionStack_h

#include "nsDeque.h"

class nsCycleCollectionTraversalCallback;

namespace mozilla {

class TransactionItem;

class TransactionStack : private nsDeque {
 public:
  enum Type { FOR_UNDO, FOR_REDO };

  explicit TransactionStack(Type aType);
  ~TransactionStack();

  void Push(TransactionItem* aTransactionItem);
  void Push(already_AddRefed<TransactionItem> aTransactionItem);
  already_AddRefed<TransactionItem> Pop();
  already_AddRefed<TransactionItem> PopBottom();
  already_AddRefed<TransactionItem> Peek();
  already_AddRefed<TransactionItem> GetItem(int32_t aIndex);
  void Clear();
  int32_t GetSize() const { return static_cast<int32_t>(nsDeque::GetSize()); }
  bool IsEmpty() const { return GetSize() == 0; }

  void DoUnlink() { Clear(); }
  void DoTraverse(nsCycleCollectionTraversalCallback& cb);

 private:
  const Type mType;
};

}  // namespace mozilla

#endif  // mozilla_TransactionStack_h