1 files changed, 170 insertions, 0 deletions
diff --git a/dom/base/nsIdentifierMapEntry.h b/dom/base/nsIdentifierMapEntry.h
new file mode 100644
index 000000000..fce506cef
--- /dev/null
+++ b/dom/base/nsIdentifierMapEntry.h
@@ -0,0 +1,170 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Base class for all our document implementations.
+ */
+
+#ifndef nsIdentifierMapEntry_h
+#define nsIdentifierMapEntry_h
+
+#include "PLDHashTable.h"
+
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/Move.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/net/ReferrerPolicy.h"
+
+#include "nsCOMArray.h"
+#include "nsCOMPtr.h"
+#include "nsContentList.h"
+#include "nsIAtom.h"
+#include "nsIDocument.h"
+#include "nsTArray.h"
+#include "nsTHashtable.h"
+
+class nsIContent;
+
+/**
+ * Right now our identifier map entries contain information for 'name'
+ * and 'id' mappings of a given string. This is so that
+ * nsHTMLDocument::ResolveName only has to do one hash lookup instead
+ * of two. It's not clear whether this still matters for performance.
+ *
+ * We also store the document.all result list here. This is mainly so that
+ * when all elements with the given ID are removed and we remove
+ * the ID's nsIdentifierMapEntry, the document.all result is released too.
+ * Perhaps the document.all results should have their own hashtable
+ * in nsHTMLDocument.
+ */
+class nsIdentifierMapEntry : public nsStringHashKey
+{
+public:
+  typedef mozilla::dom::Element Element;
+  typedef mozilla::net::ReferrerPolicy ReferrerPolicy;
+
+  explicit nsIdentifierMapEntry(const nsAString& aKey) :
+    nsStringHashKey(&aKey), mNameContentList(nullptr)
+  {
+  }
+  explicit nsIdentifierMapEntry(const nsAString* aKey) :
+    nsStringHashKey(aKey), mNameContentList(nullptr)
+  {
+  }
+  nsIdentifierMapEntry(const nsIdentifierMapEntry& aOther) :
+    nsStringHashKey(&aOther.GetKey())
+  {
+    NS_ERROR("Should never be called");
+  }
+  ~nsIdentifierMapEntry();
+
+  void AddNameElement(nsINode* aDocument, Element* aElement);
+  void RemoveNameElement(Element* aElement);
+  bool IsEmpty();
+  nsBaseContentList* GetNameContentList() {
+    return mNameContentList;
+  }
+  bool HasNameElement() const {
+    return mNameContentList && mNameContentList->Length() != 0;
+  }
+
+  /**
+   * Returns the element if we know the element associated with this
+   * id. Otherwise returns null.
+   */
+  Element* GetIdElement();
+  /**
+   * Returns the list of all elements associated with this id.
+   */
+  const nsTArray<Element*>& GetIdElements() const {
+    return mIdContentList;
+  }
+  /**
+   * If this entry has a non-null image element set (using SetImageElement),
+   * the image element will be returned, otherwise the same as GetIdElement().
+   */
+  Element* GetImageIdElement();
+  /**
+   * Append all the elements with this id to aElements
+   */
+  void AppendAllIdContent(nsCOMArray<nsIContent>* aElements);
+  /**
+   * This can fire ID change callbacks.
+   * @return true if the content could be added, false if we failed due
+   * to OOM.
+   */
+  bool AddIdElement(Element* aElement);
+  /**
+   * This can fire ID change callbacks.
+   */
+  void RemoveIdElement(Element* aElement);
+  /**
+   * Set the image element override for this ID. This will be returned by
+   * GetIdElement(true) if non-null.
+   */
+  void SetImageElement(Element* aElement);
+  bool HasIdElementExposedAsHTMLDocumentProperty();
+
+  bool HasContentChangeCallback() { return mChangeCallbacks != nullptr; }
+  void AddContentChangeCallback(nsIDocument::IDTargetObserver aCallback,
+                                void* aData, bool aForImage);
+  void RemoveContentChangeCallback(nsIDocument::IDTargetObserver aCallback,
+                                void* aData, bool aForImage);
+
+  /**
+   * Remove all elements and notify change listeners.
+   */
+  void ClearAndNotify();
+
+  void Traverse(nsCycleCollectionTraversalCallback* aCallback);
+
+  struct ChangeCallback {
+    nsIDocument::IDTargetObserver mCallback;
+    void* mData;
+    bool mForImage;
+  };
+
+  struct ChangeCallbackEntry : public PLDHashEntryHdr {
+    typedef const ChangeCallback KeyType;
+    typedef const ChangeCallback* KeyTypePointer;
+
+    explicit ChangeCallbackEntry(const ChangeCallback* aKey) :
+      mKey(*aKey) { }
+    ChangeCallbackEntry(const ChangeCallbackEntry& toCopy) :
+      mKey(toCopy.mKey) { }
+
+    KeyType GetKey() const { return mKey; }
+    bool KeyEquals(KeyTypePointer aKey) const {
+      return aKey->mCallback == mKey.mCallback &&
+             aKey->mData == mKey.mData &&
+             aKey->mForImage == mKey.mForImage;
+    }
+
+    static KeyTypePointer KeyToPointer(KeyType& aKey) { return &aKey; }
+    static PLDHashNumber HashKey(KeyTypePointer aKey)
+    {
+      return mozilla::HashGeneric(aKey->mCallback, aKey->mData);
+    }
+    enum { ALLOW_MEMMOVE = true };
+
+    ChangeCallback mKey;
+  };
+
+  size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;
+
+private:
+  void FireChangeCallbacks(Element* aOldElement, Element* aNewElement,
+                           bool aImageOnly = false);
+
+  // empty if there are no elements with this ID.
+  // The elements are stored as weak pointers.
+  nsTArray<Element*> mIdContentList;
+  RefPtr<nsBaseContentList> mNameContentList;
+  nsAutoPtr<nsTHashtable<ChangeCallbackEntry> > mChangeCallbacks;
+  RefPtr<Element> mImageElement;
+};
+
+#endif // #ifndef nsIdentifierMapEntry_h