michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsAutoPtr.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsCycleCollectionParticipant.h"
michael@0: #include "nsISupportsUtils.h"
michael@0: #include "nsTransactionItem.h"
michael@0: #include "nsTransactionStack.h"
michael@0: #include "nscore.h"
michael@0: 
michael@0: nsTransactionStack::nsTransactionStack(nsTransactionStack::Type aType)
michael@0:   : mType(aType)
michael@0: {
michael@0: }
michael@0: 
michael@0: nsTransactionStack::~nsTransactionStack()
michael@0: {
michael@0:   Clear();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsTransactionStack::Push(nsTransactionItem *aTransaction)
michael@0: {
michael@0:   if (!aTransaction) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   // The stack's bottom is the front of the deque, and the top is the back.
michael@0:   mDeque.push_back(aTransaction);
michael@0: }
michael@0: 
michael@0: already_AddRefed<nsTransactionItem>
michael@0: nsTransactionStack::Pop()
michael@0: {
michael@0:   if (mDeque.empty()) {
michael@0:     return nullptr;
michael@0:   }
michael@0:   nsRefPtr<nsTransactionItem> ret = mDeque.back().forget();
michael@0:   mDeque.pop_back();
michael@0:   return ret.forget();
michael@0: }
michael@0: 
michael@0: already_AddRefed<nsTransactionItem>
michael@0: nsTransactionStack::PopBottom()
michael@0: {
michael@0:   if (mDeque.empty()) {
michael@0:     return nullptr;
michael@0:   }
michael@0:   nsRefPtr<nsTransactionItem> ret = mDeque.front().forget();
michael@0:   mDeque.pop_front();
michael@0:   return ret.forget();
michael@0: }
michael@0: 
michael@0: already_AddRefed<nsTransactionItem>
michael@0: nsTransactionStack::Peek()
michael@0: {
michael@0:   if (mDeque.empty()) {
michael@0:     return nullptr;
michael@0:   }
michael@0:   nsRefPtr<nsTransactionItem> ret = mDeque.back();
michael@0:   return ret.forget();
michael@0: }
michael@0: 
michael@0: already_AddRefed<nsTransactionItem>
michael@0: nsTransactionStack::GetItem(int32_t aIndex)
michael@0: {
michael@0:   if (aIndex < 0 || aIndex >= static_cast<int32_t>(mDeque.size())) {
michael@0:     return nullptr;
michael@0:   }
michael@0:   nsRefPtr<nsTransactionItem> ret = mDeque[aIndex];
michael@0:   return ret.forget();
michael@0: }
michael@0: 
michael@0: void
michael@0: nsTransactionStack::Clear()
michael@0: {
michael@0:   while (!mDeque.empty()) {
michael@0:     nsRefPtr<nsTransactionItem> tx = mType == FOR_UNDO ? Pop() : PopBottom();
michael@0:   };
michael@0: }
michael@0: 
michael@0: void
michael@0: nsTransactionStack::DoTraverse(nsCycleCollectionTraversalCallback &cb)
michael@0: {
michael@0:   int32_t size = mDeque.size();
michael@0:   for (int32_t i = 0; i < size; ++i) {
michael@0:     nsTransactionItem* item = mDeque[i];
michael@0:     if (item) {
michael@0:       NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "transaction stack mDeque[i]");
michael@0:       cb.NoteNativeChild(item, NS_CYCLE_COLLECTION_PARTICIPANT(nsTransactionItem));
michael@0:     }
michael@0:   }
michael@0: }