diff --git a/src/common.hpp b/src/common.hpp
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+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014, Regents of the University of California.
+ *
+ * This file is part of NDNS (Named Data Networking Domain Name Service).
+ * See AUTHORS.md for complete list of NDNS authors and contributors.
+ *
+ * NDNS is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NDNS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NDNS, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef COMMON_HPP
+#define COMMON_HPP
+
+#ifdef NDNS_HAVE_TESTS
+#define NDNS_VIRTUAL_WITH_TESTS virtual
+#define NDNS_PUBLIC_WITH_TESTS_ELSE_PROTECTED public
+#define NDNS_PUBLIC_WITH_TESTS_ELSE_PRIVATE public
+#define NDNS_PROTECTED_WITH_TESTS_ELSE_PRIVATE protected
+#else
+#define NDNS_VIRTUAL_WITH_TESTS
+#define NDNS_PUBLIC_WITH_TESTS_ELSE_PROTECTED protected
+#define NDNS_PUBLIC_WITH_TESTS_ELSE_PRIVATE private
+#define NDNS_PROTECTED_WITH_TESTS_ELSE_PRIVATE private
+#endif
+
+
+
+
+
+#endif // COMMON_HPP