1 files changed, 76 insertions, 0 deletions
diff --git a/dom/xslt/xpath/txResultRecycler.h b/dom/xslt/xpath/txResultRecycler.h
new file mode 100644
index 0000000000..f90687b70b
--- /dev/null
+++ b/dom/xslt/xpath/txResultRecycler.h
@@ -0,0 +1,76 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 txResultRecycler_h__
+#define txResultRecycler_h__
+
+#include "nsCOMPtr.h"
+#include "txStack.h"
+
+class txAExprResult;
+class StringResult;
+class txNodeSet;
+class txXPathNode;
+class NumberResult;
+class BooleanResult;
+
+class txResultRecycler {
+ public:
+  txResultRecycler();
+  ~txResultRecycler();
+
+  void AddRef() {
+    ++mRefCnt;
+    NS_LOG_ADDREF(this, mRefCnt, "txResultRecycler", sizeof(*this));
+  }
+  void Release() {
+    --mRefCnt;
+    NS_LOG_RELEASE(this, mRefCnt, "txResultRecycler");
+    if (mRefCnt == 0) {
+      mRefCnt = 1;  // stabilize
+      delete this;
+    }
+  }
+
+  /**
+   * Returns an txAExprResult to this recycler for reuse.
+   * @param aResult  result to recycle
+   */
+  void recycle(txAExprResult* aResult);
+
+  /**
+   * Functions to return results that will be fully used by the caller.
+   * Returns nullptr on out-of-memory and an inited result otherwise.
+   */
+  nsresult getStringResult(StringResult** aResult);
+  nsresult getStringResult(const nsAString& aValue, txAExprResult** aResult);
+  nsresult getNodeSet(txNodeSet** aResult);
+  nsresult getNodeSet(txNodeSet* aNodeSet, txNodeSet** aResult);
+  nsresult getNodeSet(const txXPathNode& aNode, txAExprResult** aResult);
+  nsresult getNumberResult(double aValue, txAExprResult** aResult);
+
+  /**
+   * Functions to return a txAExprResult that is shared across several
+   * clients and must not be modified. Never returns nullptr.
+   */
+  void getEmptyStringResult(txAExprResult** aResult);
+  void getBoolResult(bool aValue, txAExprResult** aResult);
+
+  /**
+   * Functions that return non-shared resultsobjects
+   */
+  nsresult getNonSharedNodeSet(txNodeSet* aNodeSet, txNodeSet** aResult);
+
+ private:
+  nsAutoRefCnt mRefCnt;
+  txStack mStringResults;
+  txStack mNodeSetResults;
+  txStack mNumberResults;
+  RefPtr<StringResult> mEmptyStringResult;
+  RefPtr<BooleanResult> mTrueResult;
+  RefPtr<BooleanResult> mFalseResult;
+};
+
+#endif  // txResultRecycler_h__