1 files changed, 303 insertions, 0 deletions
diff --git a/dom/base/NodeInfo.h b/dom/base/NodeInfo.h
new file mode 100644
index 000000000..bdf0074e7
--- /dev/null
+++ b/dom/base/NodeInfo.h
@@ -0,0 +1,303 @@
+/* -*- 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/. */
+
+/*
+ * Class that represents a prefix/namespace/localName triple; a single
+ * nodeinfo is shared by all elements in a document that have that
+ * prefix, namespace, and localName.
+ *
+ * nsNodeInfoManagers are internal objects that manage a list of
+ * NodeInfos, every document object should hold a strong reference to
+ * a nsNodeInfoManager and every NodeInfo also holds a strong reference
+ * to their owning manager. When a NodeInfo is no longer used it will
+ * automatically remove itself from its owner manager, and when all
+ * NodeInfos have been removed from a nsNodeInfoManager and all external
+ * references are released the nsNodeInfoManager deletes itself.
+ */
+
+#ifndef mozilla_dom_NodeInfo_h___
+#define mozilla_dom_NodeInfo_h___
+
+#include "nsCycleCollectionParticipant.h"
+#include "mozilla/dom/NameSpaceConstants.h"
+#include "nsStringGlue.h"
+#include "mozilla/Attributes.h"
+#include "nsIAtom.h"
+
+class nsIDocument;
+class nsNodeInfoManager;
+
+namespace mozilla {
+namespace dom {
+
+class NodeInfo final
+{
+public:
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(NodeInfo)
+  NS_DECL_CYCLE_COLLECTION_SKIPPABLE_NATIVE_CLASS_WITH_CUSTOM_DELETE(NodeInfo)
+
+  /*
+   * Get the name from this node as a string, this does not include the prefix.
+   *
+   * For the HTML element "<body>" this will return "body" and for the XML
+   * element "<html:body>" this will return "body".
+   */
+  void GetName(nsAString& aName) const;
+
+  /*
+   * Get the name from this node as an atom, this does not include the prefix.
+   * This function never returns a null atom.
+   *
+   * For the HTML element "<body>" this will return the "body" atom and for
+   * the XML element "<html:body>" this will return the "body" atom.
+   */
+  nsIAtom* NameAtom() const
+  {
+    return mInner.mName;
+  }
+
+  /*
+   * Get the qualified name from this node as a string, the qualified name
+   * includes the prefix, if one exists.
+   *
+   * For the HTML element "<body>" this will return "body" and for the XML
+   * element "<html:body>" this will return "html:body".
+   */
+  const nsString& QualifiedName() const {
+    return mQualifiedName;
+  }
+
+  /*
+   * Returns the node's nodeName as defined in DOM Core
+   */
+  const nsString& NodeName() const {
+    return mNodeName;
+  }
+
+  /*
+   * Returns the node's localName as defined in DOM Core
+   */
+  const nsString& LocalName() const {
+    return mLocalName;
+  }
+
+  /*
+   * Get the prefix from this node as a string.
+   *
+   * For the HTML element "<body>" this will return a null string and for
+   * the XML element "<html:body>" this will return the string "html".
+   */
+  void GetPrefix(nsAString& aPrefix) const;
+
+  /*
+   * Get the prefix from this node as an atom.
+   *
+   * For the HTML element "<body>" this will return a null atom and for
+   * the XML element "<html:body>" this will return the "html" atom.
+   */
+  nsIAtom* GetPrefixAtom() const
+  {
+    return mInner.mPrefix;
+  }
+
+  /*
+   * Get the namespace URI for a node, if the node has a namespace URI.
+   */
+  void GetNamespaceURI(nsAString& aNameSpaceURI) const;
+
+  /*
+   * Get the namespace ID for a node if the node has a namespace, if not this
+   * returns kNameSpaceID_None.
+   */
+  int32_t NamespaceID() const
+  {
+    return mInner.mNamespaceID;
+  }
+
+  /*
+   * Get the nodetype for the node. Returns the values specified in nsIDOMNode
+   * for nsIDOMNode.nodeType
+   */
+  uint16_t NodeType() const
+  {
+    return mInner.mNodeType;
+  }
+
+  /*
+   * Get the extra name, used by PIs and DocTypes, for the node.
+   */
+  nsIAtom* GetExtraName() const
+  {
+    return mInner.mExtraName;
+  }
+
+  /**
+   * Get the owning node info manager. Only to be used inside Gecko, you can't
+   * really do anything with the pointer outside Gecko anyway.
+   */
+  nsNodeInfoManager* NodeInfoManager() const
+  {
+    return mOwnerManager;
+  }
+
+  /*
+   * Utility functions that can be used to check if a nodeinfo holds a specific
+   * name, name and prefix, name and prefix and namespace ID, or just
+   * namespace ID.
+   */
+  inline bool Equals(NodeInfo* aNodeInfo) const;
+
+  bool NameAndNamespaceEquals(NodeInfo* aNodeInfo) const;
+
+  bool Equals(nsIAtom* aNameAtom) const
+  {
+    return mInner.mName == aNameAtom;
+  }
+
+  bool Equals(nsIAtom* aNameAtom, nsIAtom* aPrefixAtom) const
+  {
+    return (mInner.mName == aNameAtom) && (mInner.mPrefix == aPrefixAtom);
+  }
+
+  bool Equals(nsIAtom* aNameAtom, int32_t aNamespaceID) const
+  {
+    return ((mInner.mName == aNameAtom) &&
+            (mInner.mNamespaceID == aNamespaceID));
+  }
+
+  bool Equals(nsIAtom* aNameAtom, nsIAtom* aPrefixAtom, int32_t aNamespaceID) const
+  {
+    return ((mInner.mName == aNameAtom) &&
+            (mInner.mPrefix == aPrefixAtom) &&
+            (mInner.mNamespaceID == aNamespaceID));
+  }
+
+  bool NamespaceEquals(int32_t aNamespaceID) const
+  {
+    return mInner.mNamespaceID == aNamespaceID;
+  }
+
+  inline bool Equals(const nsAString& aName) const;
+
+  inline bool Equals(const nsAString& aName, const nsAString& aPrefix) const;
+
+  inline bool Equals(const nsAString& aName, int32_t aNamespaceID) const;
+
+  inline bool Equals(const nsAString& aName, const nsAString& aPrefix, int32_t aNamespaceID) const;
+
+  bool NamespaceEquals(const nsAString& aNamespaceURI) const;
+
+  inline bool QualifiedNameEquals(nsIAtom* aNameAtom) const;
+
+  bool QualifiedNameEquals(const nsAString& aQualifiedName) const
+  {
+    return mQualifiedName == aQualifiedName;
+  }
+
+  /*
+   * Retrieve a pointer to the document that owns this node info.
+   */
+  nsIDocument* GetDocument() const
+  {
+    return mDocument;
+  }
+
+private:
+  NodeInfo() = delete; 
+  NodeInfo(const NodeInfo& aOther) = delete;
+
+  // NodeInfo is only constructed by nsNodeInfoManager which is a friend class.
+  // aName and aOwnerManager may not be null.
+  NodeInfo(nsIAtom* aName, nsIAtom* aPrefix, int32_t aNamespaceID,
+           uint16_t aNodeType, nsIAtom* aExtraName,
+           nsNodeInfoManager* aOwnerManager);
+
+  ~NodeInfo();
+
+public:
+  bool CanSkip();
+
+  /**
+   * This method gets called by the cycle collector when it's time to delete
+   * this object.
+   */
+  void DeleteCycleCollectable();
+
+protected:
+  /*
+   * NodeInfoInner is used for two things:
+   *
+   *   1. as a member in nsNodeInfo for holding the name, prefix and
+   *      namespace ID
+   *   2. as the hash key in the hash table in nsNodeInfoManager
+   *
+   * NodeInfoInner does not do any kind of reference counting,
+   * that's up to the user of this class. Since NodeInfoInner is
+   * typically used as a member of NodeInfo, the hash table doesn't
+   * need to delete the keys. When the value (NodeInfo) is deleted
+   * the key is automatically deleted.
+   */
+
+  class NodeInfoInner
+  {
+  public:
+    NodeInfoInner()
+      : mName(nullptr), mPrefix(nullptr), mNamespaceID(kNameSpaceID_Unknown),
+        mNodeType(0), mNameString(nullptr), mExtraName(nullptr)
+    {
+    }
+    NodeInfoInner(nsIAtom *aName, nsIAtom *aPrefix, int32_t aNamespaceID,
+                    uint16_t aNodeType, nsIAtom* aExtraName)
+      : mName(aName), mPrefix(aPrefix), mNamespaceID(aNamespaceID),
+        mNodeType(aNodeType), mNameString(nullptr), mExtraName(aExtraName)
+    {
+    }
+    NodeInfoInner(const nsAString& aTmpName, nsIAtom *aPrefix,
+                    int32_t aNamespaceID, uint16_t aNodeType)
+      : mName(nullptr), mPrefix(aPrefix), mNamespaceID(aNamespaceID),
+        mNodeType(aNodeType), mNameString(&aTmpName), mExtraName(nullptr)
+    {
+    }
+
+    nsCOMPtr<nsIAtom> mName;
+    nsCOMPtr<nsIAtom> mPrefix;
+    int32_t             mNamespaceID;
+    uint16_t            mNodeType; // As defined by nsIDOMNode.nodeType
+    const nsAString*    mNameString;
+    nsCOMPtr<nsIAtom> mExtraName; // Only used by PIs and DocTypes
+  };
+
+  // nsNodeInfoManager needs to pass mInner to the hash table.
+  friend class ::nsNodeInfoManager;
+
+  // This is a non-owning reference, but it's safe since it's set to nullptr
+  // by nsNodeInfoManager::DropDocumentReference when the document is destroyed.
+  nsIDocument* MOZ_NON_OWNING_REF mDocument; // Cache of mOwnerManager->mDocument
+
+  NodeInfoInner mInner;
+
+  RefPtr<nsNodeInfoManager> mOwnerManager;
+
+  /*
+   * Members for various functions of mName+mPrefix that we can be
+   * asked to compute.
+   */
+
+  // Qualified name
+  nsString mQualifiedName;
+
+  // nodeName for the node.
+  nsString mNodeName;
+
+  // localName for the node. This is either equal to mInner.mName, or a
+  // void string, depending on mInner.mNodeType.
+  nsString mLocalName;
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif /* mozilla_dom_NodeInfo_h___ */