| /* |
| * Copyright (C) 1999 Lars Knoll (knoll@kde.org) |
| * Copyright (C) 2000 Frederik Holljen (frederik.holljen@hig.no) |
| * Copyright (C) 2001 Peter Kelly (pmk@post.com) |
| * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com) |
| * Copyright (C) 2004, 2008 Apple Inc. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| * |
| */ |
| |
| #include "config.h" |
| #include "TreeWalker.h" |
| |
| #include "ContainerNode.h" |
| #include "NodeTraversal.h" |
| #include "ScriptWrappableInlines.h" |
| #include <wtf/TZoneMallocInlines.h> |
| |
| namespace WebCore { |
| |
| WTF_MAKE_TZONE_ALLOCATED_IMPL(TreeWalker); |
| |
| TreeWalker::TreeWalker(Node& rootNode, unsigned long whatToShow, RefPtr<NodeFilter>&& filter) |
| : NodeIteratorBase(rootNode, whatToShow, WTF::move(filter)) |
| , m_current(root()) |
| { |
| } |
| |
| void TreeWalker::setCurrentNode(Node& node) |
| { |
| m_current = node; |
| } |
| |
| inline Node* TreeWalker::setCurrent(Ref<Node>&& node) |
| { |
| m_current = WTF::move(node); |
| return m_current.ptr(); |
| } |
| |
| ExceptionOr<Node*> TreeWalker::parentNode() |
| { |
| RefPtr node = m_current.ptr(); |
| while (node != &root()) { |
| node = node->parentNode(); |
| if (!node) |
| return nullptr; |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| if (filterResult.returnValue() == NodeFilter::FILTER_ACCEPT) |
| return setCurrent(node.releaseNonNull()); |
| } |
| return nullptr; |
| } |
| |
| ExceptionOr<Node*> TreeWalker::firstChild() |
| { |
| for (RefPtr node = m_current->firstChild(); node; ) { |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| switch (filterResult.returnValue()) { |
| case NodeFilter::FILTER_ACCEPT: |
| m_current = node.releaseNonNull(); |
| return m_current.ptr(); |
| case NodeFilter::FILTER_SKIP: |
| if (node->firstChild()) { |
| node = node->firstChild(); |
| continue; |
| } |
| break; |
| case NodeFilter::FILTER_REJECT: |
| break; |
| } |
| do { |
| if (node->nextSibling()) { |
| node = node->nextSibling(); |
| break; |
| } |
| RefPtr parent = node->parentNode(); |
| if (!parent || parent == &root() || parent == m_current.ptr()) |
| return nullptr; |
| node = WTF::move(parent); |
| } while (node); |
| } |
| return nullptr; |
| } |
| |
| ExceptionOr<Node*> TreeWalker::lastChild() |
| { |
| for (RefPtr node = m_current->lastChild(); node; ) { |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| switch (filterResult.returnValue()) { |
| case NodeFilter::FILTER_ACCEPT: |
| m_current = node.releaseNonNull(); |
| return m_current.ptr(); |
| case NodeFilter::FILTER_SKIP: |
| if (node->lastChild()) { |
| node = node->lastChild(); |
| continue; |
| } |
| break; |
| case NodeFilter::FILTER_REJECT: |
| break; |
| } |
| do { |
| if (node->previousSibling()) { |
| node = node->previousSibling(); |
| break; |
| } |
| RefPtr parent = node->parentNode(); |
| if (!parent || parent == &root() || parent == m_current.ptr()) |
| return nullptr; |
| node = WTF::move(parent); |
| } while (node); |
| } |
| return nullptr; |
| } |
| |
| template<TreeWalker::SiblingTraversalType type> ExceptionOr<Node*> TreeWalker::traverseSiblings() |
| { |
| RefPtr node = m_current.ptr(); |
| if (node == &root()) |
| return nullptr; |
| |
| auto isNext = type == SiblingTraversalType::Next; |
| while (true) { |
| for (RefPtr sibling = isNext ? node->nextSibling() : node->previousSibling(); sibling; ) { |
| auto filterResult = acceptNode(*sibling); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| if (filterResult.returnValue() == NodeFilter::FILTER_ACCEPT) { |
| m_current = sibling.releaseNonNull(); |
| return m_current.ptr(); |
| } |
| node = sibling; |
| sibling = isNext ? sibling->firstChild() : sibling->lastChild(); |
| if (filterResult.returnValue() == NodeFilter::FILTER_REJECT || !sibling) |
| sibling = isNext ? node->nextSibling() : node->previousSibling(); |
| } |
| node = node->parentNode(); |
| if (!node || node == &root()) |
| return nullptr; |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| if (filterResult.returnValue() == NodeFilter::FILTER_ACCEPT) |
| return nullptr; |
| } |
| } |
| |
| ExceptionOr<Node*> TreeWalker::previousSibling() |
| { |
| return traverseSiblings<SiblingTraversalType::Previous>(); |
| } |
| |
| ExceptionOr<Node*> TreeWalker::nextSibling() |
| { |
| return traverseSiblings<SiblingTraversalType::Next>(); |
| } |
| |
| ExceptionOr<Node*> TreeWalker::previousNode() |
| { |
| if (!filter()) { |
| if (m_current.ptr() == &root()) |
| return nullptr; |
| for (RefPtr node = NodeTraversal::previous(m_current); node; node = NodeTraversal::previous(*node)) { |
| if (matchesWhatToShow(*node)) |
| return setCurrent(node.releaseNonNull()); |
| if (node == &root()) |
| break; |
| } |
| return nullptr; |
| } |
| RefPtr node = m_current.ptr(); |
| while (node != &root()) { |
| while (RefPtr previousSibling = node->previousSibling()) { |
| node = WTF::move(previousSibling); |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| auto acceptNodeResult = filterResult.returnValue(); |
| if (acceptNodeResult == NodeFilter::FILTER_REJECT) |
| continue; |
| while (RefPtr lastChild = node->lastChild()) { |
| node = WTF::move(lastChild); |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| acceptNodeResult = filterResult.returnValue(); |
| if (acceptNodeResult == NodeFilter::FILTER_REJECT) |
| break; |
| } |
| if (acceptNodeResult == NodeFilter::FILTER_ACCEPT) { |
| m_current = node.releaseNonNull(); |
| return m_current.ptr(); |
| } |
| } |
| if (node == &root()) |
| return nullptr; |
| RefPtr parent = node->parentNode(); |
| if (!parent) |
| return nullptr; |
| node = WTF::move(parent); |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| if (filterResult.returnValue() == NodeFilter::FILTER_ACCEPT) |
| return setCurrent(node.releaseNonNull()); |
| } |
| return nullptr; |
| } |
| |
| ExceptionOr<Node*> TreeWalker::nextNode() |
| { |
| if (!filter()) { |
| for (RefPtr node = NodeTraversal::next(m_current, &root()); node; node = NodeTraversal::next(*node, &root())) { |
| if (matchesWhatToShow(*node)) |
| return setCurrent(node.releaseNonNull()); |
| } |
| return nullptr; |
| } |
| RefPtr node = m_current.ptr(); |
| Children: |
| while (RefPtr firstChild = node->firstChild()) { |
| node = WTF::move(firstChild); |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| if (filterResult.returnValue() == NodeFilter::FILTER_ACCEPT) |
| return setCurrent(node.releaseNonNull()); |
| if (filterResult.returnValue() == NodeFilter::FILTER_REJECT) |
| break; |
| } |
| while (RefPtr nextSibling = NodeTraversal::nextSkippingChildren(*node, &root())) { |
| node = WTF::move(nextSibling); |
| |
| auto filterResult = acceptNode(*node); |
| if (filterResult.hasException()) |
| return filterResult.releaseException(); |
| |
| if (filterResult.returnValue() == NodeFilter::FILTER_ACCEPT) |
| return setCurrent(node.releaseNonNull()); |
| if (filterResult.returnValue() == NodeFilter::FILTER_SKIP) |
| goto Children; |
| } |
| return nullptr; |
| } |
| |
| } // namespace WebCore |
