pingserver: refactor for separate responsibility

refs #2793

Change-Id: I39e1794fa276d168427eac0164d481109adc6cfe
diff --git a/tools/ping/server/tracer.hpp b/tools/ping/server/tracer.hpp
new file mode 100644
index 0000000..1971f50
--- /dev/null
+++ b/tools/ping/server/tracer.hpp
@@ -0,0 +1,56 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2015,  Arizona Board of Regents.
+ *
+ * This file is part of ndn-tools (Named Data Networking Essential Tools).
+ * See AUTHORS.md for complete list of ndn-tools authors and contributors.
+ *
+ * ndn-tools 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.
+ *
+ * ndn-tools 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
+ * ndn-tools, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @author Eric Newberry <enewberry@email.arizona.edu>
+ */
+
+#ifndef NDN_TOOLS_PING_SERVER_TRACER_HPP
+#define NDN_TOOLS_PING_SERVER_TRACER_HPP
+
+#include "core/common.hpp"
+
+#include "ping-server.hpp"
+
+namespace ndn {
+namespace ping {
+namespace server {
+
+/**
+ * @brief logs ping responses
+ */
+class Tracer : noncopyable
+{
+public:
+  Tracer(PingServer& pingServer, const Options& options);
+
+  /**
+   * Prints ping information when interest received
+   * @param name interest name received
+   */
+  void
+  onReceive(const Name& name);
+
+private:
+  const Options& m_options;
+};
+
+} // namespace server
+} // namespace ping
+} // namespace ndn
+
+#endif //NDN_TOOLS_PING_SERVER_TRACER_HPP
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