osx: Implement auto-upgrade function using Sparkle

During the upgrade, NFD and ndn-autoupdate will be stopped (and, if
enabled, automatically started with new versions).

Change-Id: I010ae4a8aa6f99a0039d58065ab7eb0c9189a979
diff --git a/src/osx-auto-update-sparkle.hpp b/src/osx-auto-update-sparkle.hpp
new file mode 100644
index 0000000..716f1dc
--- /dev/null
+++ b/src/osx-auto-update-sparkle.hpp
@@ -0,0 +1,53 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2017, Regents of the University of California.
+ *
+ * This file is part of NFD Control Center.  See AUTHORS.md for complete list of NFD
+ * authors and contributors.
+ *
+ * NFD Control Center 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 Control Center 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
+ * Control Center, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef NCC_OSX_AUTO_UPDATE_SPARKLE_HPP
+#define NCC_OSX_AUTO_UPDATE_SPARKLE_HPP
+
+#include "config.hpp"
+
+#ifndef OSX_BUILD
+#error "Cannot be included for non-OSX build"
+#endif // OSX_BUILD
+
+#include <string>
+#include <ndn-cxx/util/backports.hpp>
+
+namespace ndn {
+namespace ncc {
+
+class OsxAutoUpdateSparkle
+{
+public:
+  OsxAutoUpdateSparkle(const std::string& updateUrl);
+
+  ~OsxAutoUpdateSparkle();
+
+  void
+  checkForUpdates();
+
+private:
+  class Impl;
+  unique_ptr<Impl> m_impl;
+};
+
+} // namespace ncc
+} // namespace ndn
+
+#endif // NCC_OSX_AUTO_UPDATE_SPARKLE_HPP