editor/txmgr/TransactionStack.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef mozilla_TransactionStack_h
   7 #define mozilla_TransactionStack_h
   8
   9 #include "mozilla/AlreadyAddRefed.h"
  10 #include "nsDeque.h"
  11
  12 class nsCycleCollectionTraversalCallback;
  13
  14 namespace mozilla {
  15
  16 class TransactionItem;
  17
  18 class TransactionStack : private nsRefPtrDeque<TransactionItem> {
  19  public:
  20   enum Type { FOR_UNDO, FOR_REDO };
  21
  22   explicit TransactionStack(Type aType);
  23   ~TransactionStack();
  24
  25   void Push(TransactionItem* aTransactionItem);
  26   void Push(already_AddRefed<TransactionItem> aTransactionItem);
  27   already_AddRefed<TransactionItem> Pop();
  28   already_AddRefed<TransactionItem> PopBottom();
  29   already_AddRefed<TransactionItem> Peek() const;
  30   already_AddRefed<TransactionItem> GetItemAt(size_t aIndex) const;
  31   void Clear();
  32   size_t GetSize() const { return nsRefPtrDeque<TransactionItem>::GetSize(); }
  33   bool IsEmpty() const { return GetSize() == 0; }
  34
  35   void DoUnlink() { Clear(); }
  36   void DoTraverse(nsCycleCollectionTraversalCallback& cb);
  37
  38  private:
  39   const Type mType;
  40 };
  41
  42 }  // namespace mozilla
  43
  44 #endif  // mozilla_TransactionStack_h