C++ HTMLStackItem::token方法代码示例

void HTMLFormattingElementList::tryToEnsureNoahsArkConditionQuickly(HTMLStackItem* newItem, Vector<HTMLStackItem*>& remainingCandidates)
{
    ASSERT(remainingCandidates.isEmpty());

    if (m_entries.size() < kNoahsArkCapacity)
        return;

    // Use a vector with inline capacity to avoid a malloc in the common case
    // of a quickly ensuring the condition.
    Vector<HTMLStackItem*, 10> candidates;

    size_t newItemAttributeCount = attributeCount(newItem->token());

    for (size_t i = m_entries.size(); i; ) {
        --i;
        Entry& entry = m_entries[i];
        if (entry.isMarker())
            break;

        // Quickly reject obviously non-matching candidates.
        HTMLStackItem* candidate = entry.stackItem().get();
        if (newItem->localName() != candidate->localName() || newItem->namespaceURI() != candidate->namespaceURI())
            continue;
        if (attributeCount(candidate->token()) != newItemAttributeCount)
            continue;

        candidates.append(candidate);
    }

    if (candidates.size() < kNoahsArkCapacity)
        return; // There's room for the new element in the ark. There's no need to copy out the remainingCandidates.

    remainingCandidates.append(candidates);
}

void HTMLFormattingElementList::ensureNoahsArkCondition(HTMLStackItem* newItem)
{
    Vector<HTMLStackItem*> candidates;
    tryToEnsureNoahsArkConditionQuickly(newItem, candidates);
    if (candidates.isEmpty())
        return;

    // We pre-allocate and re-use this second vector to save one malloc per
    // attribute that we verify.
    Vector<HTMLStackItem*> remainingCandidates;
    remainingCandidates.reserveInitialCapacity(candidates.size());

    const Vector<Attribute>& attributes = newItem->token()->attributes();
    for (size_t i = 0; i < attributes.size(); ++i) {
        const Attribute& attribute = attributes[i];

        for (size_t j = 0; j < candidates.size(); ++j) {
            HTMLStackItem* candidate = candidates[j];

            // These properties should already have been checked by tryToEnsureNoahsArkConditionQuickly.
            ASSERT(attributeCount(newItem->token()) == attributeCount(candidate->token()));
            ASSERT(newItem->localName() == candidate->localName() && newItem->namespaceURI() == candidate->namespaceURI());

            Attribute* candidateAttribute = candidate->token()->getAttributeItem(attribute.name());
            if (candidateAttribute && candidateAttribute->value() == attribute.value())
                remainingCandidates.append(candidate);
        }

        if (remainingCandidates.size() < kNoahsArkCapacity)
            return;

        candidates.swap(remainingCandidates);
        remainingCandidates.shrink(0);
    }

    // Inductively, we shouldn't spin this loop very many times. It's possible,
    // however, that we wil spin the loop more than once because of how the
    // formatting element list gets permuted.
    for (size_t i = kNoahsArkCapacity - 1; i < candidates.size(); ++i)
        remove(candidates[i]->element());
}