editor/txmgr/src/nsTransactionStack.cpp
author ted.mielczarek@gmail.com
Mon, 16 Jul 2007 14:00:26 -0700
changeset 3527 82217acf2a91b4c8076237352963a60278a6b61a
parent 1 9b2a99adc05e53cd4010de512f50118594756650
child 22573 cda0ae16a8a8ebf85d77dd807316e86552aa18ee
permissions -rw-r--r--
bug 388320 - package crashreporter xpt (+ rename airbag module to crashreporter). r=bsmedberg

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
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 *
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 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
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 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
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 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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 * the provisions above, a recipient may use your version of this file under
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#include "nsITransaction.h"
#include "nsTransactionItem.h"
#include "nsTransactionStack.h"
#include "nsCOMPtr.h"

nsTransactionStack::nsTransactionStack()
  : mQue(0)
{
  nsTransactionReleaseFunctor* theFunctor=new nsTransactionReleaseFunctor();
  mQue.SetDeallocator(theFunctor);
} 

nsTransactionStack::~nsTransactionStack()
{
  Clear();
}

nsresult
nsTransactionStack::Push(nsTransactionItem *aTransaction)
{
  if (!aTransaction)
    return NS_ERROR_NULL_POINTER;

  /* nsDeque's Push() method adds new items at the back
   * of the deque.
   */
  mQue.Push(aTransaction);

  return NS_OK;
}

nsresult
nsTransactionStack::Pop(nsTransactionItem **aTransaction)
{
  if (!aTransaction)
    return NS_ERROR_NULL_POINTER;

  /* nsDeque is a FIFO, so the top of our stack is actually
   * the back of the deque.
   */
  *aTransaction = (nsTransactionItem *)mQue.Pop();

  return NS_OK;
}

nsresult
nsTransactionStack::PopBottom(nsTransactionItem **aTransaction)
{
  if (!aTransaction)
    return NS_ERROR_NULL_POINTER;

  /* nsDeque is a FIFO, so the bottom of our stack is actually
   * the front of the deque.
   */
  *aTransaction = (nsTransactionItem *)mQue.PopFront();

  return NS_OK;
}

nsresult
nsTransactionStack::Peek(nsTransactionItem **aTransaction)
{
  if (!aTransaction)
    return NS_ERROR_NULL_POINTER;

  if (!mQue.GetSize()) {
    *aTransaction = 0;
    return NS_OK;
  }

  *aTransaction = (nsTransactionItem *)(mQue.Last());

  return NS_OK;
}

nsresult
nsTransactionStack::GetItem(PRInt32 aIndex, nsTransactionItem **aTransaction)
{
  if (!aTransaction)
    return NS_ERROR_NULL_POINTER;

  if (aIndex < 0 || aIndex >= mQue.GetSize())
    return NS_ERROR_FAILURE;

  *aTransaction = (nsTransactionItem *)(mQue.ObjectAt(aIndex));

  return NS_OK;
}

nsresult
nsTransactionStack::Clear(void)
{
  nsTransactionItem *tx = 0;
  nsresult result    = NS_OK;

  /* Pop all transactions off the stack and release them. */

  result = Pop(&tx);

  if (NS_FAILED(result))
    return result;

  while (tx) {
    delete tx;

    result = Pop(&tx);

    if (NS_FAILED(result))
      return result;
  }

  return NS_OK;
}

nsresult
nsTransactionStack::GetSize(PRInt32 *aStackSize)
{
  if (!aStackSize)
    return NS_ERROR_NULL_POINTER;

  *aStackSize = mQue.GetSize();

  return NS_OK;
}

nsTransactionRedoStack::~nsTransactionRedoStack()
{
  Clear();
}

nsresult
nsTransactionRedoStack::Clear(void)
{
  nsTransactionItem *tx = 0;
  nsresult result       = NS_OK;

  /* When clearing a Redo stack, we have to clear from the
   * bottom of the stack towards the top!
   */

  result = PopBottom(&tx);

  if (NS_FAILED(result))
    return result;

  while (tx) {
    delete tx;

    result = PopBottom(&tx);

    if (NS_FAILED(result))
      return result;
  }

  return NS_OK;
}

void *
nsTransactionReleaseFunctor::operator()(void *aObject)
{
  nsTransactionItem *item = (nsTransactionItem *)aObject;
  delete item;
  return 0;
}