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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 01:47:29 +0000 |
commit | 0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch) | |
tree | a31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /dom/base/TreeWalker.cpp | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream/115.8.0esr.tar.xz firefox-esr-upstream/115.8.0esr.zip |
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/base/TreeWalker.cpp')
-rw-r--r-- | dom/base/TreeWalker.cpp | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/dom/base/TreeWalker.cpp b/dom/base/TreeWalker.cpp new file mode 100644 index 0000000000..e7a39dff13 --- /dev/null +++ b/dom/base/TreeWalker.cpp @@ -0,0 +1,329 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=4 et sw=2 tw=80: */ +/* 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 TreeWalker + */ + +#include "mozilla/dom/TreeWalker.h" + +#include "nsIContent.h" +#include "nsError.h" +#include "nsINode.h" +#include "nsContentUtils.h" +#include "mozilla/dom/NodeFilterBinding.h" +#include "mozilla/dom/TreeWalkerBinding.h" + +namespace mozilla::dom { + +/* + * Factories, constructors and destructors + */ + +TreeWalker::TreeWalker(nsINode* aRoot, uint32_t aWhatToShow, + NodeFilter* aFilter) + : nsTraversal(aRoot, aWhatToShow, aFilter), mCurrentNode(aRoot) {} + +TreeWalker::~TreeWalker() { /* destructor code */ +} + +/* + * nsISupports and cycle collection stuff + */ + +NS_IMPL_CYCLE_COLLECTION(TreeWalker, mFilter, mCurrentNode, mRoot) + +// QueryInterface implementation for TreeWalker +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(TreeWalker) + NS_INTERFACE_MAP_ENTRY(nsISupports) +NS_INTERFACE_MAP_END + +// Have to pass in dom::TreeWalker because a11y has an a11y::TreeWalker that +// passes TreeWalker so refcount logging would get confused on the name +// collision. +NS_IMPL_CYCLE_COLLECTING_ADDREF(dom::TreeWalker) +NS_IMPL_CYCLE_COLLECTING_RELEASE(dom::TreeWalker) + +void TreeWalker::SetCurrentNode(nsINode& aNode, ErrorResult& aResult) { + aResult = nsContentUtils::CheckSameOrigin(mRoot, &aNode); + if (aResult.Failed()) { + return; + } + + mCurrentNode = &aNode; +} + +already_AddRefed<nsINode> TreeWalker::ParentNode(ErrorResult& aResult) { + nsCOMPtr<nsINode> node = mCurrentNode; + + while (node && node != mRoot) { + node = node->GetParentNode(); + + if (node) { + int16_t filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + mCurrentNode = node; + return node.forget(); + } + } + } + + return nullptr; +} + +already_AddRefed<nsINode> TreeWalker::FirstChild(ErrorResult& aResult) { + return FirstChildInternal(false, aResult); +} + +already_AddRefed<nsINode> TreeWalker::LastChild(ErrorResult& aResult) { + return FirstChildInternal(true, aResult); +} + +already_AddRefed<nsINode> TreeWalker::PreviousSibling(ErrorResult& aResult) { + return NextSiblingInternal(true, aResult); +} + +already_AddRefed<nsINode> TreeWalker::NextSibling(ErrorResult& aResult) { + return NextSiblingInternal(false, aResult); +} + +already_AddRefed<nsINode> TreeWalker::PreviousNode(ErrorResult& aResult) { + nsCOMPtr<nsINode> node = mCurrentNode; + + while (node != mRoot) { + while (nsINode* previousSibling = node->GetPreviousSibling()) { + node = previousSibling; + + int16_t filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + + nsINode* lastChild; + while (filtered != NodeFilter_Binding::FILTER_REJECT && + (lastChild = node->GetLastChild())) { + node = lastChild; + filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + } + + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + mCurrentNode = node; + return node.forget(); + } + } + + if (node == mRoot) { + break; + } + + node = node->GetParentNode(); + if (!node) { + break; + } + + int16_t filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + mCurrentNode = node; + return node.forget(); + } + } + + return nullptr; +} + +already_AddRefed<nsINode> TreeWalker::NextNode(ErrorResult& aResult) { + int16_t filtered = + NodeFilter_Binding::FILTER_ACCEPT; // pre-init for inner loop + + nsCOMPtr<nsINode> node = mCurrentNode; + + while (1) { + nsINode* firstChild; + while (filtered != NodeFilter_Binding::FILTER_REJECT && + (firstChild = node->GetFirstChild())) { + node = firstChild; + + filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + // Node found + mCurrentNode = node; + return node.forget(); + } + } + + nsINode* sibling = nullptr; + nsINode* temp = node; + do { + if (temp == mRoot) break; + + sibling = temp->GetNextSibling(); + if (sibling) break; + + temp = temp->GetParentNode(); + } while (temp); + + if (!sibling) break; + + node = sibling; + + // Found a sibling. Either ours or ancestor's + filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + // Node found + mCurrentNode = node; + return node.forget(); + } + } + + return nullptr; +} + +/* + * TreeWalker helper functions + */ + +/* + * Implements FirstChild and LastChild which only vary in which direction + * they search. + * @param aReversed Controls whether we search forwards or backwards + * @param aResult Whether we threw or not. + * @returns The desired node. Null if no child is found + */ +already_AddRefed<nsINode> TreeWalker::FirstChildInternal(bool aReversed, + ErrorResult& aResult) { + nsCOMPtr<nsINode> node = + aReversed ? mCurrentNode->GetLastChild() : mCurrentNode->GetFirstChild(); + + while (node) { + int16_t filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + + switch (filtered) { + case NodeFilter_Binding::FILTER_ACCEPT: + // Node found + mCurrentNode = node; + return node.forget(); + case NodeFilter_Binding::FILTER_SKIP: { + nsINode* child = + aReversed ? node->GetLastChild() : node->GetFirstChild(); + if (child) { + node = child; + continue; + } + break; + } + case NodeFilter_Binding::FILTER_REJECT: + // Keep searching + break; + } + + do { + nsINode* sibling = + aReversed ? node->GetPreviousSibling() : node->GetNextSibling(); + if (sibling) { + node = sibling; + break; + } + + nsINode* parent = node->GetParentNode(); + + if (!parent || parent == mRoot || parent == mCurrentNode) { + return nullptr; + } + + node = parent; + + } while (node); + } + + return nullptr; +} + +/* + * Implements NextSibling and PreviousSibling which only vary in which + * direction they search. + * @param aReversed Controls whether we search forwards or backwards + * @param aResult Whether we threw or not. + * @returns The desired node. Null if no child is found + */ +already_AddRefed<nsINode> TreeWalker::NextSiblingInternal( + bool aReversed, ErrorResult& aResult) { + nsCOMPtr<nsINode> node = mCurrentNode; + + if (node == mRoot) { + return nullptr; + } + + while (1) { + nsINode* sibling = + aReversed ? node->GetPreviousSibling() : node->GetNextSibling(); + + while (sibling) { + node = sibling; + + int16_t filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + // Node found + mCurrentNode = node; + return node.forget(); + } + + // If rejected or no children, try a sibling + if (filtered == NodeFilter_Binding::FILTER_REJECT || + !(sibling = + aReversed ? node->GetLastChild() : node->GetFirstChild())) { + sibling = + aReversed ? node->GetPreviousSibling() : node->GetNextSibling(); + } + } + + node = node->GetParentNode(); + + if (!node || node == mRoot) { + return nullptr; + } + + // Is parent transparent in filtered view? + int16_t filtered = TestNode(node, aResult); + if (aResult.Failed()) { + return nullptr; + } + if (filtered == NodeFilter_Binding::FILTER_ACCEPT) { + return nullptr; + } + } +} + +bool TreeWalker::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto, + JS::MutableHandle<JSObject*> aReflector) { + return TreeWalker_Binding::Wrap(aCx, this, aGivenProto, aReflector); +} + +} // namespace mozilla::dom |