ping: Code refactoring

Change-Id: I8b4e2c9dd3ba3adfae8d296a5635b048b35cf593
Refs: #3137
diff --git a/tools/ping/server/ndn-ping-server.cpp b/tools/ping/server/ndn-ping-server.cpp
index 0a02805..2b9db41 100644
--- a/tools/ping/server/ndn-ping-server.cpp
+++ b/tools/ping/server/ndn-ping-server.cpp
@@ -30,6 +30,69 @@
 namespace ping {
 namespace server {
 
+class Runner : noncopyable
+{
+public:
+  explicit
+  Runner(const Options& options)
+    : m_options(options)
+    , m_pingServer(m_face, m_keyChain, options)
+    , m_tracer(m_pingServer, options)
+    , m_signalSetInt(m_face.getIoService(), SIGINT)
+  {
+    m_signalSetInt.async_wait(bind(&Runner::afterIntSignal, this, _1));
+
+    m_pingServer.afterFinish.connect([this] {
+        this->cancel();
+      });
+  }
+
+  int
+  run()
+  {
+    try {
+      m_pingServer.start();
+      m_face.processEvents();
+    }
+    catch (std::exception& e) {
+      std::cerr << "ERROR: " << e.what() << std::endl;
+      return 1;
+    }
+
+    std::cout << "\n--- ping server " << m_options.prefix << " ---" << std::endl;
+    std::cout << m_pingServer.getNPings() << " packets processed" << std::endl;
+
+    return 0;
+  }
+
+private:
+  void
+  cancel()
+  {
+    m_signalSetInt.cancel();
+    m_pingServer.stop();
+  }
+
+  void
+  afterIntSignal(const boost::system::error_code& errorCode)
+  {
+    if (errorCode == boost::asio::error::operation_aborted) {
+      return;
+    }
+
+    cancel();
+  }
+
+private:
+  const Options& m_options;
+  Face m_face;
+  KeyChain m_keyChain;
+  PingServer m_pingServer;
+  Tracer m_tracer;
+
+  boost::asio::signal_set m_signalSetInt;
+};
+
 static time::milliseconds
 getMinimumFreshnessPeriod()
 {
@@ -48,36 +111,6 @@
   exit(2);
 }
 
-static void
-printStatistics(PingServer& pingServer, Options& options)
-{
-  std::cout << "\n--- ping server " << options.prefix << " ---" << std::endl;
-  std::cout << pingServer.getNPings() << " packets processed" << std::endl;
-}
-
-/**
- * @brief SIGINT handler: exits
- * @param pingServer pingServer instance
- * @param options options
- */
-static void
-onSigInt(PingServer& pingServer, Options& options, Face& face)
-{
-  printStatistics(pingServer, options);
-  face.shutdown();
-  face.getIoService().stop();
-  exit(1);
-}
-
-/**
- * @brief outputs errors to cerr
- */
-static void
-onError(std::string msg)
-{
-  std::cerr << "ERROR: " << msg << std::endl;
-}
-
 int
 main(int argc, char* argv[])
 {
@@ -169,30 +202,8 @@
     usage(visibleOptDesc);
   }
 
-  boost::asio::io_service ioService;
-  Face face(ioService);
-  PingServer pingServer(face, options);
-  Tracer tracer(pingServer, options);
-
-  boost::asio::signal_set signalSetInt(face.getIoService(), SIGINT);
-  signalSetInt.async_wait(bind(&onSigInt, ref(pingServer), ref(options), ref(face)));
-
   std::cout << "PING SERVER " << options.prefix << std::endl;
-
-  try {
-    pingServer.run();
-  }
-  catch (std::exception& e) {
-    onError(e.what());
-    face.getIoService().stop();
-    return 1;
-  }
-
-  printStatistics(pingServer, options);
-  face.shutdown();
-  face.getIoService().stop();
-
-  return 0;
+  return Runner(options).run();
 }
 
 } // namespace server
@@ -203,4 +214,4 @@
 main(int argc, char** argv)
 {
   return ndn::ping::server::main(argc, argv);
-}
\ No newline at end of file
+}
diff --git a/tools/ping/server/ping-server.cpp b/tools/ping/server/ping-server.cpp
index 799fa8d..08d17bf 100644
--- a/tools/ping/server/ping-server.cpp
+++ b/tools/ping/server/ping-server.cpp
@@ -26,11 +26,13 @@
 namespace ping {
 namespace server {
 
-PingServer::PingServer(Face& face, const Options& options)
+PingServer::PingServer(Face& face, KeyChain& keyChain, const Options& options)
   : m_options(options)
+  , m_keyChain(keyChain)
   , m_name(options.prefix)
   , m_nPings(0)
   , m_face(face)
+  , m_registeredPrefixId(nullptr)
 {
   shared_ptr<Buffer> b = make_shared<Buffer>();
   b->assign(m_options.payloadSize, 'a');
@@ -38,22 +40,22 @@
 }
 
 void
-PingServer::run()
-{
-  start();
-
-  m_face.getIoService().run();
-}
-
-void
 PingServer::start()
 {
   m_name.append("ping");
-  m_face.setInterestFilter(m_name,
-                           bind(&PingServer::onInterest,
-                                this, _2),
-                           bind(&PingServer::onRegisterFailed,
-                                this, _2));
+  m_registeredPrefixId = m_face.setInterestFilter(m_name,
+                                                  bind(&PingServer::onInterest,
+                                                       this, _2),
+                                                  bind(&PingServer::onRegisterFailed,
+                                                       this, _2));
+}
+
+void
+PingServer::stop()
+{
+  if (m_registeredPrefixId != nullptr) {
+    m_face.unsetInterestFilter(m_registeredPrefixId);
+  }
 }
 
 int
@@ -77,8 +79,7 @@
 
   ++m_nPings;
   if (m_options.shouldLimitSatisfied && m_options.nMaxPings > 0 && m_options.nMaxPings == m_nPings) {
-    m_face.shutdown();
-    m_face.getIoService().stop();
+    afterFinish();
   }
 }
 
@@ -90,4 +91,4 @@
 
 } // namespace server
 } // namespace ping
-} // namespace ndn
\ No newline at end of file
+} // namespace ndn
diff --git a/tools/ping/server/ping-server.hpp b/tools/ping/server/ping-server.hpp
index 242a54a..ff8e1c7 100644
--- a/tools/ping/server/ping-server.hpp
+++ b/tools/ping/server/ping-server.hpp
@@ -48,14 +48,20 @@
 class PingServer : noncopyable
 {
 public:
-  PingServer(Face& face, const Options& options);
+  PingServer(Face& face, KeyChain& keyChain, const Options& options);
 
   /**
-   * Signals when Interest received
+   * @brief Signals when Interest received
+   *
    * @param name incoming interest name
    */
   signal::Signal<PingServer, Name> afterReceive;
 
+  /**
+   * @brief Signals when finished pinging
+   */
+  signal::Signal<PingServer> afterFinish;
+
   /** @brief starts ping server
    *
    *  If options.shouldLimitSatisfied is false, this method does not return unless there's an error.
@@ -66,11 +72,19 @@
 
   /**
    * @brief starts the Interest filter
+   *
+   * @note This method is non-blocking and caller need to call face.processEvents()
    */
   void
   start();
 
   /**
+   * @brief Unregister set interest filter
+   */
+  void
+  stop();
+
+  /**
    * @brief gets the number of pings received
    */
   int
@@ -78,14 +92,16 @@
 
 private:
   /**
-   * Called when interest received
+   * @brief Called when interest received
+   *
    * @param interest incoming interest
    */
   void
   onInterest(const Interest& interest);
 
   /**
-   * Called when prefix registration failed
+   * @brief Called when prefix registration failed
+   *
    * @param reason reason for failure
    */
   void
@@ -93,15 +109,17 @@
 
 private:
   const Options& m_options;
+  KeyChain& m_keyChain;
   Name m_name;
-  KeyChain m_keyChain;
   int m_nPings;
   Face& m_face;
   Block m_payload;
+
+  const RegisteredPrefixId* m_registeredPrefixId;
 };
 
 } // namespace server
 } // namespace ping
 } // namespace ndn
 
-#endif //NDN_TOOLS_PING_SERVER_PING_SERVER_HPP
\ No newline at end of file
+#endif //NDN_TOOLS_PING_SERVER_PING_SERVER_HPP
diff --git a/tools/ping/server/tracer.cpp b/tools/ping/server/tracer.cpp
index fa4e2c8..305fc5d 100644
--- a/tools/ping/server/tracer.cpp
+++ b/tools/ping/server/tracer.cpp
@@ -43,4 +43,4 @@
 
 } // namespace server
 } // namespace ping
-} // namespace ndn
\ No newline at end of file
+} // namespace ndn
diff --git a/tools/ping/server/tracer.hpp b/tools/ping/server/tracer.hpp
index 1971f50..b8b6952 100644
--- a/tools/ping/server/tracer.hpp
+++ b/tools/ping/server/tracer.hpp
@@ -39,7 +39,7 @@
   Tracer(PingServer& pingServer, const Options& options);
 
   /**
-   * Prints ping information when interest received
+   * @brief Prints ping information when interest received
    * @param name interest name received
    */
   void
@@ -53,4 +53,4 @@
 } // namespace ping
 } // namespace ndn
 
-#endif //NDN_TOOLS_PING_SERVER_TRACER_HPP
\ No newline at end of file
+#endif // NDN_TOOLS_PING_SERVER_TRACER_HPP