diff --git a/common.hpp b/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 NSL (NDN Signature Logger).
+ * See AUTHORS.md for complete list of NSL authors and contributors.
+ *
+ * NSL 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.
+ *
+ * NSL 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
+ * NSL, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * \author Yingdi Yu <yingdi@cs.ucla.edu>
+ */
+
+#ifndef NSL_COMMON_HPP
+#define NSL_COMMON_HPP
+
+#include "config.hpp"
+
+#ifdef WITH_TESTS
+#define VIRTUAL_WITH_TESTS virtual
+#define PUBLIC_WITH_TESTS_ELSE_PROTECTED public
+#define PUBLIC_WITH_TESTS_ELSE_PRIVATE public
+#define PROTECTED_WITH_TESTS_ELSE_PRIVATE protected
+#else
+#define VIRTUAL_WITH_TESTS
+#define PUBLIC_WITH_TESTS_ELSE_PROTECTED protected
+#define PUBLIC_WITH_TESTS_ELSE_PRIVATE private
+#define PROTECTED_WITH_TESTS_ELSE_PRIVATE private
+#endif
+
+#include <cstddef>
+#include <list>
+#include <set>
+#include <queue>
+#include <vector>
+
+#include <ndn-cxx/common.hpp>
+#include <ndn-cxx/interest.hpp>
+#include <ndn-cxx/data.hpp>
+
+#include <boost/algorithm/string.hpp>
+#include <boost/asio.hpp>
+#include <boost/assert.hpp>
+#include <boost/lexical_cast.hpp>
+#include <boost/noncopyable.hpp>
+#include <boost/property_tree/ptree.hpp>
+#include <boost/scoped_ptr.hpp>
+
+namespace nsl {
+
+using std::size_t;
+
+using boost::noncopyable;
+using boost::scoped_ptr;
+
+using ndn::shared_ptr;
+using ndn::weak_ptr;
+using ndn::enable_shared_from_this;
+using ndn::make_shared;
+using ndn::static_pointer_cast;
+using ndn::dynamic_pointer_cast;
+using ndn::const_pointer_cast;
+using ndn::function;
+using ndn::bind;
+using ndn::ref;
+using ndn::cref;
+
+using ndn::Interest;
+using ndn::Data;
+using ndn::Name;
+using ndn::Exclude;
+using ndn::Block;
+
+namespace tlv {
+using namespace ndn::Tlv;
+}
+
+namespace name = ndn::name;
+namespace time = ndn::time;
+
+} // namespace nsl
+
+#endif // NSL_COMMON_HPP