1 files changed, 130 insertions, 0 deletions
diff --git a/dom/xul/templates/nsRDFQuery.h b/dom/xul/templates/nsRDFQuery.h
new file mode 100644
index 000000000..572cce4d3
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+++ b/dom/xul/templates/nsRDFQuery.h
@@ -0,0 +1,130 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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/. */
+
+#ifndef nsRDFQuery_h__
+#define nsRDFQuery_h__
+
+#include "nsISimpleEnumerator.h"
+#include "nsCycleCollectionParticipant.h"
+#include "mozilla/Attributes.h"
+
+#define NS_ITEMPLATERDFQUERY_IID \
+  {0x8929ff60, 0x1c9c, 0x4d87, \
+    { 0xac, 0x02, 0x09, 0x14, 0x15, 0x3b, 0x48, 0xc4 }}
+
+class nsXULTemplateQueryProcessorRDF;
+
+/**
+ * A compiled query in the RDF query processor. This interface should not be
+ * used directly outside of the RDF query processor.
+ */
+class nsITemplateRDFQuery : public nsISupports
+{
+public:
+    NS_DECLARE_STATIC_IID_ACCESSOR(NS_ITEMPLATERDFQUERY_IID)
+
+    // return the processor the query was created from
+    virtual nsXULTemplateQueryProcessorRDF* Processor() = 0;  // not addrefed
+
+    // return the member variable for the query
+    virtual nsIAtom* GetMemberVariable() = 0; // not addrefed
+
+    // return the <query> node the query was compiled from
+    virtual void GetQueryNode(nsIDOMNode** aQueryNode) = 0;
+
+    // remove any results that are cached by the query
+    virtual void ClearCachedResults() = 0;
+};
+
+class nsRDFQuery final : public nsITemplateRDFQuery
+{
+    ~nsRDFQuery() { Finish(); }
+
+public:
+
+    explicit nsRDFQuery(nsXULTemplateQueryProcessorRDF* aProcessor)
+      : mProcessor(aProcessor),
+        mSimple(false),
+        mRoot(nullptr),
+        mCachedResults(nullptr)
+    { }
+
+    NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+    NS_DECL_CYCLE_COLLECTION_CLASS(nsRDFQuery)
+
+    /**
+     * Retrieve the root node in the rule network
+     * @return the root node in the rule network
+     */
+    TestNode* GetRoot() { return mRoot; }
+
+    void SetRoot(TestNode* aRoot) { mRoot = aRoot; }
+
+    void GetQueryNode(nsIDOMNode** aQueryNode) override
+    {
+       *aQueryNode = mQueryNode;
+       NS_IF_ADDREF(*aQueryNode);
+    }
+
+    void SetQueryNode(nsIDOMNode* aQueryNode)
+    {
+       mQueryNode = aQueryNode;
+    }
+
+    // an optimization is used when several queries all use the simple query
+    // syntax. Since simple queries can only generate one possible set of
+    // results, they only need to be calculated once and reused for every
+    // simple query. The results may be cached in the query for this purpose.
+    // If successful, this method takes ownership of aInstantiations.
+    nsresult SetCachedResults(nsXULTemplateQueryProcessorRDF* aProcessor,
+                              const InstantiationSet& aInstantiations);
+
+    // grab the cached results, if any, causing the caller to take ownership
+    // of them. This also has the effect of setting the cached results in this
+    // nsRDFQuery to null.
+    void UseCachedResults(nsISimpleEnumerator** aResults);
+
+    // clear the cached results
+    void ClearCachedResults() override
+    {
+        mCachedResults = nullptr;
+    }
+
+    nsXULTemplateQueryProcessorRDF* Processor() override { return mProcessor; }
+
+    nsIAtom* GetMemberVariable() override { return mMemberVariable; }
+
+    bool IsSimple() { return mSimple; }
+
+    void SetSimple() { mSimple = true; }
+
+    // the reference and member variables for the query
+    nsCOMPtr<nsIAtom> mRefVariable;
+    nsCOMPtr<nsIAtom> mMemberVariable;
+
+protected:
+
+    nsXULTemplateQueryProcessorRDF* mProcessor;
+
+    // true if the query is a simple rule (one with a default query)
+    bool mSimple;
+
+    /**
+     * The root node in the network for this query
+     */
+    TestNode *mRoot;
+
+    // the <query> node
+    nsCOMPtr<nsIDOMNode> mQueryNode;
+
+    // used for simple rules since their results are all determined in one step
+    nsCOMPtr<nsISimpleEnumerator> mCachedResults;
+
+    void Finish();
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsITemplateRDFQuery, NS_ITEMPLATERDFQUERY_IID)
+
+#endif // nsRDFQuery_h__