rib: ReadvertiseDestination availability

refs: #3818

Change-Id: Ifc2875ba38025595f3d6a8f8207f5ec126f93c90
diff --git a/rib/readvertise/readvertise-destination.cpp b/rib/readvertise/readvertise-destination.cpp
new file mode 100644
index 0000000..c064b23
--- /dev/null
+++ b/rib/readvertise/readvertise-destination.cpp
@@ -0,0 +1,41 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2017,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD 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.
+ *
+ * NFD 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
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "readvertise-destination.hpp"
+
+namespace nfd {
+namespace rib {
+
+void
+ReadvertiseDestination::setAvailability(bool isAvailable)
+{
+  if (m_isAvailable != isAvailable) {
+    m_isAvailable = isAvailable;
+    afterAvailabilityChange(isAvailable);
+  }
+}
+
+} // namespace rib
+} // namespace nfd