face: use NetworkMonitor::listNetworkInterfaces() in tests

refs #4021

Change-Id: I6daccc3872a0c6b2e2e49390bc5881c796503926
diff --git a/tests/daemon/face/test-netif-ip.cpp b/tests/daemon/face/test-netif-ip.cpp
new file mode 100644
index 0000000..3471ba3
--- /dev/null
+++ b/tests/daemon/face/test-netif-ip.cpp
@@ -0,0 +1,122 @@
+/* -*- 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 "test-netif-ip.hpp"
+#include "core/global-io.hpp"
+#include <ndn-cxx/net/network-monitor.hpp>
+
+namespace nfd {
+namespace tests {
+
+std::vector<shared_ptr<const NetworkInterface>>
+collectNetworkInterfaces(bool allowCached)
+{
+  using ndn::net::NetworkMonitor;
+
+  static std::vector<shared_ptr<const NetworkInterface>> cached;
+  // cached.empty() indicates there's no cached list of netifs.
+  // Although it could also mean a system without any network interface, this situation is rare
+  // because the loopback interface is present on almost all systems.
+
+  if (!allowCached || cached.empty()) {
+    NetworkMonitor netmon(getGlobalIoService());
+    if ((netmon.getCapabilities() & NetworkMonitor::CAP_ENUM) == 0) {
+      BOOST_THROW_EXCEPTION(NetworkMonitor::Error("NetworkMonitor::CAP_ENUM is unavailable"));
+    }
+
+    netmon.onEnumerationCompleted.connect([] { getGlobalIoService().stop(); });
+    getGlobalIoService().run();
+    getGlobalIoService().reset();
+
+    cached = netmon.listNetworkInterfaces();
+  }
+
+  return cached;
+}
+
+namespace {
+
+template<typename E>
+bool
+matchTristate(E e, bool b)
+{
+  return (e == E::DontCare) ||
+         (e == E::Yes && b) ||
+         (e == E::No && !b);
+}
+
+template<AddressFamily AF>
+typename IpAddressFromFamily<AF>::type
+fromIpAddress(const boost::asio::ip::address& a);
+
+template<>
+IpAddressFromFamily<AddressFamily::V4>::type
+fromIpAddress<AddressFamily::V4>(const boost::asio::ip::address& a)
+{
+  return a.to_v4();
+}
+
+template<>
+IpAddressFromFamily<AddressFamily::V6>::type
+fromIpAddress<AddressFamily::V6>(const boost::asio::ip::address& a)
+{
+  return a.to_v6();
+}
+
+} // unnamed namespace
+
+template<AddressFamily AF>
+typename IpAddressFromFamily<AF>::type
+getTestIp(LoopbackAddress loopback, MulticastInterface mcast)
+{
+  for (const auto& interface : collectNetworkInterfaces()) {
+    if (!interface->isUp() ||
+        !matchTristate(loopback, interface->isLoopback()) ||
+        !matchTristate(mcast, interface->canMulticast())) {
+      continue;
+    }
+    for (const auto& address : interface->getNetworkAddresses()) {
+      if (isAddressFamily<AF>(address) &&
+          !address.getIp().is_unspecified() &&
+          address.getScope() != ndn::net::AddressScope::NOWHERE &&
+          address.getScope() != ndn::net::AddressScope::LINK && // link-local addresses are not supported yet (#1428)
+          matchTristate(loopback, address.getIp().is_loopback())) {
+        return fromIpAddress<AF>(address.getIp());
+      }
+    }
+  }
+  return {};
+}
+
+template
+IpAddressFromFamily<AddressFamily::V4>::type
+getTestIp<AddressFamily::V4>(LoopbackAddress loopback, MulticastInterface mcast);
+
+template
+IpAddressFromFamily<AddressFamily::V6>::type
+getTestIp<AddressFamily::V6>(LoopbackAddress loopback, MulticastInterface mcast);
+
+} // namespace tests
+} // namespace nfd