Merge 143840

Source/WebCore/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 41 matching lines @@
 #include "TreeScopeAdopter.h"
 #include <wtf/Vector.h>
 #include <wtf/text/AtomicString.h>
 #include <wtf/text/CString.h>
 
 namespace WebCore {
 
 struct SameSizeAsTreeScope {
     virtual ~SameSizeAsTreeScope();
     void* pointers[8];
+    int ints[1];
 };
 
 COMPILE_ASSERT(sizeof(TreeScope) == sizeof(SameSizeAsTreeScope), treescope_should_stay_small);
 
 using namespace HTMLNames;
 
 TreeScope::TreeScope(ContainerNode* rootNode, Document* document)
     : m_rootNode(rootNode)
     , m_documentScope(document)
     , m_parentTreeScope(document)
+    , m_guardRefCount(0)
     , m_idTargetObserverRegistry(IdTargetObserverRegistry::create())
 {
     ASSERT(rootNode);
     ASSERT(document);
     ASSERT(rootNode != document);
+    m_parentTreeScope->guardRef();
+    m_rootNode->setTreeScope(this);
 }
 
 TreeScope::TreeScope(Document* document)
     : m_rootNode(document)
     , m_documentScope(document)
     , m_parentTreeScope(0)
+    , m_guardRefCount(0)
     , m_idTargetObserverRegistry(IdTargetObserverRegistry::create())
 {
     ASSERT(document);
+    m_rootNode->setTreeScope(this);
 }
 
 TreeScope::TreeScope()
     : m_rootNode(0)
     , m_documentScope(0)
     , m_parentTreeScope(0)
+    , m_guardRefCount(0)
 {
 }
 
 TreeScope::~TreeScope()
 {
+    ASSERT(!m_guardRefCount);
+    m_rootNode->setTreeScope(noDocumentInstance());
+
     if (m_selection) {
         m_selection->clearTreeScope();
         m_selection = 0;
     }
+
+    if (m_parentTreeScope)
+        m_parentTreeScope->guardDeref();
 }
 
 void TreeScope::destroyTreeScopeData()
 {
     m_elementsById.clear();
     m_imageMapsByName.clear();
     m_labelsByForAttribute.clear();
 }
 
 void TreeScope::clearDocumentScope()
 {
     ASSERT(rootNode()->isDocumentNode());
     m_documentScope = 0;
 }
 
 void TreeScope::setParentTreeScope(TreeScope* newParentScope)
 {
     // A document node cannot be re-parented.
     ASSERT(!rootNode()->isDocumentNode());
     // Every scope other than document needs a parent scope.
     ASSERT(newParentScope);
 
+    newParentScope->guardRef();
+    if (m_parentTreeScope)
+        m_parentTreeScope->guardDeref();
     m_parentTreeScope = newParentScope;
     setDocumentScope(newParentScope->documentScope());
 }
 
 Element* TreeScope::getElementById(const AtomicString& elementId) const
 {
     if (elementId.isEmpty())
         return 0;
     if (!m_elementsById)
         return 0;
@@ skipping 275 matching lines @@
     listTreeScopes(nodeB, treeScopesB);
 
     size_t indexA = treeScopesA.size();
     size_t indexB = treeScopesB.size();
 
     for (; indexA > 0 && indexB > 0 && treeScopesA[indexA - 1] == treeScopesB[indexB - 1]; --indexA, --indexB) { }
 
     return treeScopesA[indexA] == treeScopesB[indexB] ? treeScopesA[indexA] : 0;
 }
 
+#ifndef NDEBUG
+bool TreeScope::deletionHasBegun()
+{
+    return rootNode() && rootNode()->m_deletionHasBegun;
+}
+
+void TreeScope::beginDeletion()
+{
+    ASSERT(this != noDocumentInstance());
+    rootNode()->m_deletionHasBegun = true;
+}
+#endif
+
+int TreeScope::refCount() const
+{
+    if (Node* root = rootNode())
+        return root->refCount();
+    return 0;
+}
+
 } // namespace WebCore