gecko-dev/dom/base/NodeIterator.h
Xidorn Quan 31f5ebf083 Bug 1287706 part 1 - Make CallbackObjectHolder movable (and actually move-only). r=smaug
So that we can avoid unnecessary refcount changes.

MozReview-Commit-ID: 4Mk9SJTj6AS

--HG--
extra : source : c35643f76ef33b6cdce115c8de0dfae8abccd644
2016-07-28 12:00:06 +10:00

123 lines
3.4 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* 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/. */
/*
* Implementation of DOM Traversal's nsIDOMNodeIterator
*/
#ifndef mozilla_dom_NodeIterator_h
#define mozilla_dom_NodeIterator_h
#include "nsIDOMNodeIterator.h"
#include "nsTraversal.h"
#include "nsCycleCollectionParticipant.h"
#include "nsStubMutationObserver.h"
class nsINode;
class nsIDOMNode;
namespace mozilla {
namespace dom {
class NodeIterator final : public nsIDOMNodeIterator,
public nsTraversal,
public nsStubMutationObserver
{
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_NSIDOMNODEITERATOR
NodeIterator(nsINode *aRoot,
uint32_t aWhatToShow,
NodeFilterHolder aFilter);
NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(NodeIterator, nsIDOMNodeIterator)
// WebIDL API
nsINode* Root() const
{
return mRoot;
}
nsINode* GetReferenceNode() const
{
return mPointer.mNode;
}
bool PointerBeforeReferenceNode() const
{
return mPointer.mBeforeNode;
}
uint32_t WhatToShow() const
{
return mWhatToShow;
}
already_AddRefed<NodeFilter> GetFilter()
{
return mFilter.ToWebIDLCallback();
}
already_AddRefed<nsINode> NextNode(ErrorResult& aResult)
{
return NextOrPrevNode(&NodePointer::MoveToNext, aResult);
}
already_AddRefed<nsINode> PreviousNode(ErrorResult& aResult)
{
return NextOrPrevNode(&NodePointer::MoveToPrevious, aResult);
}
// The XPCOM Detach() is fine for our purposes
bool WrapObject(JSContext *cx, JS::Handle<JSObject*> aGivenProto, JS::MutableHandle<JSObject*> aReflector);
private:
virtual ~NodeIterator();
struct NodePointer {
NodePointer() : mNode(nullptr) {}
NodePointer(nsINode *aNode, bool aBeforeNode);
typedef bool (NodePointer::*MoveToMethodType)(nsINode*);
bool MoveToNext(nsINode *aRoot);
bool MoveToPrevious(nsINode *aRoot);
bool MoveForward(nsINode *aRoot, nsINode *aNode);
void MoveBackward(nsINode *aParent, nsINode *aNode);
void AdjustAfterRemoval(nsINode *aRoot, nsINode *aContainer, nsIContent *aChild, nsIContent *aPreviousSibling);
void Clear() { mNode = nullptr; }
nsINode *mNode;
bool mBeforeNode;
};
// Implementation for some of our XPCOM getters
typedef already_AddRefed<nsINode> (NodeIterator::*NodeGetter)(ErrorResult&);
inline nsresult ImplNodeGetter(NodeGetter aGetter, nsIDOMNode** aRetval)
{
mozilla::ErrorResult rv;
nsCOMPtr<nsINode> node = (this->*aGetter)(rv);
if (rv.Failed()) {
return rv.StealNSResult();
}
*aRetval = node ? node.forget().take()->AsDOMNode() : nullptr;
return NS_OK;
}
// Have to return a strong ref, because the act of testing the node can
// remove it from the DOM so we're holding the only ref to it.
already_AddRefed<nsINode>
NextOrPrevNode(NodePointer::MoveToMethodType aMove, ErrorResult& aResult);
NodePointer mPointer;
NodePointer mWorkingPointer;
};
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_NodeIterator_h