Source/core/dom/DocumentOrderedMap.cpp

/*
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 *
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#include "config.h"
#include "core/dom/DocumentOrderedMap.h"

#include "core/HTMLNames.h"
#include "core/dom/Element.h"
#include "core/dom/ElementTraversal.h"
#include "core/dom/TreeScope.h"
#include "core/html/HTMLMapElement.h"

namespace WebCore {

using namespace HTMLNames;

inline bool keyMatchesId(StringImpl* key, Element& element)
{
    return element.getIdAttribute().impl() == key;
}

inline bool keyMatchesMapName(StringImpl* key, Element& element)
{
    return isHTMLMapElement(element) && toHTMLMapElement(element).getName().impl() == key;
}

inline bool keyMatchesLowercasedMapName(StringImpl* key, Element& element)
{
    return isHTMLMapElement(element) && toHTMLMapElement(element).getName().lower().impl() == key;
}

inline bool keyMatchesLabelForAttribute(StringImpl* key, Element& element)
{
    return isHTMLLabelElement(element) && element.getAttribute(forAttr).impl() == key;
}

void DocumentOrderedMap::add(StringImpl* key, Element* element)
{
    ASSERT(key);
    ASSERT(element);

    Map::AddResult addResult = m_map.add(key, adoptPtr(new MapEntry(element)));
    if (addResult.isNewEntry)
        return;

    OwnPtr<MapEntry>& entry = addResult.storedValue->value;
    ASSERT(entry->count);
    entry->element = 0;
    entry->count++;
    entry->orderedList.clear();
}

void DocumentOrderedMap::remove(StringImpl* key, Element* element)
{
    ASSERT(key);
    ASSERT(element);

    Map::iterator it = m_map.find(key);
    if (it == m_map.end())
        return;

    OwnPtr<MapEntry>& entry = it->value;
    ASSERT(entry->count);
    if (entry->count == 1) {
        ASSERT(!entry->element || entry->element == element);
        m_map.remove(it);
    } else {
        if (entry->element == element) {
            ASSERT(entry->orderedList.isEmpty() || entry->orderedList.first() == element);
            entry->element = entry->orderedList.size() > 1 ? entry->orderedList[1] : 0;
        }
        entry->count--;
        entry->orderedList.clear();
    }
}

template<bool keyMatches(StringImpl*, Element&)>
inline Element* DocumentOrderedMap::get(StringImpl* key, const TreeScope* scope) const
{
    ASSERT(key);
    ASSERT(scope);

    MapEntry* entry = m_map.get(key);
    if (!entry)
        return 0;

    ASSERT(entry->count);
    if (entry->element)
        return entry->element;

    // We know there's at least one node that matches; iterate to find the first one.
    for (Element* element = ElementTraversal::firstWithin(scope->rootNode()); element; element = ElementTraversal::next(*element)) {
        if (!keyMatches(key, *element))
            continue;
        entry->element = element;
        return element;
    }
    ASSERT_NOT_REACHED();
    return 0;
}

Element* DocumentOrderedMap::getElementById(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesId>(key, scope);
}

const Vector<Element*>& DocumentOrderedMap::getAllElementsById(StringImpl* key, const TreeScope* scope) const
{
    ASSERT(key);
    ASSERT(scope);
    DEFINE_STATIC_LOCAL(Vector<Element*>, emptyVector, ());

    Map::iterator it = m_map.find(key);
    if (it == m_map.end())
        return emptyVector;

    OwnPtr<MapEntry>& entry = it->value;
    ASSERT(entry->count);

    if (entry->orderedList.isEmpty()) {
        entry->orderedList.reserveCapacity(entry->count);
        for (Element* element = entry->element ? entry->element : ElementTraversal::firstWithin(scope->rootNode()); entry->orderedList.size() < entry->count; element = ElementTraversal::next(*element)) {
            ASSERT(element);
            if (!keyMatchesId(key, *element))
                continue;
            entry->orderedList.uncheckedAppend(element);
        }
        if (!entry->element)
            entry->element = entry->orderedList.first();
    }

    return entry->orderedList;
}

Element* DocumentOrderedMap::getElementByMapName(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesMapName>(key, scope);
}

Element* DocumentOrderedMap::getElementByLowercasedMapName(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesLowercasedMapName>(key, scope);
}

Element* DocumentOrderedMap::getElementByLabelForAttribute(StringImpl* key, const TreeScope* scope) const
{
    return get<keyMatchesLabelForAttribute>(key, scope);
}

} // namespace WebCore