HTMLFormattingElementList.cpp [plain text]
#include "config.h"
#include "HTMLFormattingElementList.h"
#ifndef NDEBUG
#include <stdio.h>
#endif
namespace WebCore {
static const size_t kNoahsArkCapacity = 3;
HTMLFormattingElementList::HTMLFormattingElementList()
{
}
HTMLFormattingElementList::~HTMLFormattingElementList()
{
}
Element* HTMLFormattingElementList::closestElementInScopeWithName(const AtomicString& targetName)
{
for (unsigned i = 1; i <= m_entries.size(); ++i) {
const Entry& entry = m_entries[m_entries.size() - i];
if (entry.isMarker())
return nullptr;
if (entry.stackItem()->matchesHTMLTag(targetName))
return &entry.element();
}
return nullptr;
}
bool HTMLFormattingElementList::contains(Element& element)
{
return !!find(element);
}
auto HTMLFormattingElementList::find(Element& element) -> Entry*
{
size_t index = m_entries.reverseFind(&element);
if (index != notFound) {
return &m_entries[index];
}
return nullptr;
}
auto HTMLFormattingElementList::bookmarkFor(Element& element) -> Bookmark
{
size_t index = m_entries.reverseFind(&element);
ASSERT(index != notFound);
return Bookmark(at(index));
}
void HTMLFormattingElementList::swapTo(Element& oldElement, Ref<HTMLStackItem>&& newItem, const Bookmark& bookmark)
{
ASSERT(contains(oldElement));
ASSERT(!contains(newItem->element()));
if (!bookmark.hasBeenMoved()) {
ASSERT(&bookmark.mark().element() == &oldElement);
bookmark.mark().replaceElement(newItem.copyRef());
return;
}
size_t index = &bookmark.mark() - &first();
ASSERT_WITH_SECURITY_IMPLICATION(index < size());
m_entries.insert(index + 1, WTFMove(newItem));
remove(oldElement);
}
void HTMLFormattingElementList::append(Ref<HTMLStackItem>&& item)
{
ensureNoahsArkCondition(item);
m_entries.append(WTFMove(item));
}
void HTMLFormattingElementList::remove(Element& element)
{
size_t index = m_entries.reverseFind(&element);
if (index != notFound)
m_entries.remove(index);
}
void HTMLFormattingElementList::appendMarker()
{
m_entries.append(Entry::MarkerEntry);
}
void HTMLFormattingElementList::clearToLastMarker()
{
while (m_entries.size()) {
bool shouldStop = m_entries.last().isMarker();
m_entries.removeLast();
if (shouldStop)
break;
}
}
void HTMLFormattingElementList::tryToEnsureNoahsArkConditionQuickly(HTMLStackItem& newItem, Vector<HTMLStackItem*>& remainingCandidates)
{
ASSERT(remainingCandidates.isEmpty());
if (m_entries.size() < kNoahsArkCapacity)
return;
Vector<HTMLStackItem*, 10> candidates;
size_t newItemAttributeCount = newItem.attributes().size();
for (size_t i = m_entries.size(); i; ) {
--i;
Entry& entry = m_entries[i];
if (entry.isMarker())
break;
HTMLStackItem* candidate = entry.stackItem();
if (newItem.localName() != candidate->localName() || newItem.namespaceURI() != candidate->namespaceURI())
continue;
if (candidate->attributes().size() != newItemAttributeCount)
continue;
candidates.append(candidate);
}
if (candidates.size() < kNoahsArkCapacity)
return;
remainingCandidates.appendVector(candidates);
}
void HTMLFormattingElementList::ensureNoahsArkCondition(HTMLStackItem& newItem)
{
Vector<HTMLStackItem*> candidates;
tryToEnsureNoahsArkConditionQuickly(newItem, candidates);
if (candidates.isEmpty())
return;
Vector<HTMLStackItem*> remainingCandidates;
remainingCandidates.reserveInitialCapacity(candidates.size());
for (auto& attribute : newItem.attributes()) {
for (auto& candidate : candidates) {
ASSERT(newItem.attributes().size() == candidate->attributes().size());
ASSERT(newItem.localName() == candidate->localName() && newItem.namespaceURI() == candidate->namespaceURI());
auto* candidateAttribute = candidate->findAttribute(attribute.name());
if (candidateAttribute && candidateAttribute->value() == attribute.value())
remainingCandidates.uncheckedAppend(candidate);
}
if (remainingCandidates.size() < kNoahsArkCapacity)
return;
candidates.swap(remainingCandidates);
remainingCandidates.shrink(0);
}
for (size_t i = kNoahsArkCapacity - 1; i < candidates.size(); ++i)
remove(candidates[i]->element());
}
#if ENABLE(TREE_DEBUGGING)
void HTMLFormattingElementList::show()
{
for (unsigned i = 1; i <= m_entries.size(); ++i) {
const Entry& entry = m_entries[m_entries.size() - i];
if (entry.isMarker())
fprintf(stderr, "marker\n");
else
entry.element().showNode();
}
}
#endif
}