1 files changed, 104 insertions, 0 deletions
diff --git a/chromium/third_party/WebKit/Source/core/dom/WeakNodeMap.cpp b/chromium/third_party/WebKit/Source/core/dom/WeakNodeMap.cpp
new file mode 100644
index 00000000000..34296c004b7
--- /dev/null
+++ b/chromium/third_party/WebKit/Source/core/dom/WeakNodeMap.cpp
@@ -0,0 +1,104 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "core/dom/WeakNodeMap.h"
+
+#include "core/dom/Node.h"
+
+namespace WebCore {
+
+class NodeToWeakNodeMaps {
+public:
+    bool addedToMap(Node*, WeakNodeMap*);
+    bool removedFromMap(Node*, WeakNodeMap*);
+    void nodeDestroyed(Node*);
+
+    static NodeToWeakNodeMaps& instance()
+    {
+        DEFINE_STATIC_LOCAL(NodeToWeakNodeMaps, self, ());
+        return self;
+    }
+
+private:
+    typedef Vector<WeakNodeMap*, 1> MapList;
+    typedef HashMap<Node*, OwnPtr<MapList> > NodeToMapList;
+    NodeToMapList m_nodeToMapList;
+};
+
+bool NodeToWeakNodeMaps::addedToMap(Node* node, WeakNodeMap* map)
+{
+    NodeToMapList::AddResult result = m_nodeToMapList.add(node, nullptr);
+    if (result.isNewEntry)
+        result.storedValue->value = adoptPtr(new MapList());
+    result.storedValue->value->append(map);
+    return result.isNewEntry;
+}
+
+bool NodeToWeakNodeMaps::removedFromMap(Node* node, WeakNodeMap* map)
+{
+    NodeToMapList::iterator it = m_nodeToMapList.find(node);
+    ASSERT(it != m_nodeToMapList.end());
+    MapList* mapList = it->value.get();
+    size_t position = mapList->find(map);
+    ASSERT(position != kNotFound);
+    mapList->remove(position);
+    if (mapList->size() == 0) {
+        m_nodeToMapList.remove(it);
+        return true;
+    }
+    return false;
+}
+
+void NodeToWeakNodeMaps::nodeDestroyed(Node* node)
+{
+    OwnPtr<NodeToWeakNodeMaps::MapList> maps = m_nodeToMapList.take(node);
+    for (size_t i = 0; i < maps->size(); i++)
+        (*maps)[i]->nodeDestroyed(node);
+}
+
+WeakNodeMap::~WeakNodeMap()
+{
+    NodeToWeakNodeMaps& allMaps = NodeToWeakNodeMaps::instance();
+    for (NodeToValue::iterator it = m_nodeToValue.begin(); it != m_nodeToValue.end(); ++it) {
+        Node* node = it->key;
+        if (allMaps.removedFromMap(node, this))
+            node->clearFlag(Node::HasWeakReferencesFlag);
+    }
+}
+
+void WeakNodeMap::put(Node* node, int value)
+{
+    ASSERT(!m_nodeToValue.contains(node));
+    m_nodeToValue.set(node, value);
+    m_valueToNode.set(value, node);
+
+    NodeToWeakNodeMaps& maps = NodeToWeakNodeMaps::instance();
+    if (maps.addedToMap(node, this))
+        node->setFlag(Node::HasWeakReferencesFlag);
+}
+
+int WeakNodeMap::value(Node* node)
+{
+    return m_nodeToValue.get(node);
+}
+
+Node* WeakNodeMap::node(int value)
+{
+    return m_valueToNode.get(value);
+}
+
+void WeakNodeMap::nodeDestroyed(Node* node)
+{
+    int value = m_nodeToValue.take(node);
+    ASSERT(value);
+    m_valueToNode.remove(value);
+}
+
+void WeakNodeMap::notifyNodeDestroyed(Node* node)
+{
+    NodeToWeakNodeMaps::instance().nodeDestroyed(node);
+}
+
+}