tools: refactor nfd-status

refs #3658

Change-Id: Ia347074bea802eba5f539208e276e849a60db8a4
diff --git a/tools/nfd-status/main.cpp b/tools/nfd-status/main.cpp
new file mode 100644
index 0000000..a3033a6
--- /dev/null
+++ b/tools/nfd-status/main.cpp
@@ -0,0 +1,199 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2016,  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 "version.hpp"
+#include <ndn-cxx/security/validator-null.hpp>
+
+#include <boost/program_options/options_description.hpp>
+#include <boost/program_options/variables_map.hpp>
+#include <boost/program_options/parsers.hpp>
+
+#include "status-report.hpp"
+#include "forwarder-general-module.hpp"
+#include "channel-module.hpp"
+#include "face-module.hpp"
+#include "fib-module.hpp"
+#include "rib-module.hpp"
+#include "strategy-choice-module.hpp"
+
+namespace nfd {
+namespace tools {
+namespace nfd_status {
+
+enum class OutputFormat
+{
+  XML = 1,
+  TEXT = 2
+};
+
+struct Options
+{
+  OutputFormat output = OutputFormat::TEXT;
+  bool wantForwarderGeneral = false;
+  bool wantChannels = false;
+  bool wantFaces = false;
+  bool wantFib = false;
+  bool wantRib = false;
+  bool wantStrategyChoice = false;
+};
+
+static void
+showUsage(std::ostream& os, const boost::program_options::options_description& cmdOptions)
+{
+  os << "Usage: nfd-status [options]\n\n"
+     << "Show NFD version and status information.\n\n"
+     << cmdOptions;
+}
+
+/** \brief parse command line, and show usage if necessary
+ *  \return if first item is -1, caller should retrieve and display StatusReport;
+ *          otherwise, caller should immediately exit with the specified exit code
+ */
+static std::tuple<int, Options>
+parseCommandLine(int argc, const char* const* argv)
+{
+  Options options;
+
+  namespace po = boost::program_options;
+  po::options_description cmdOptions("Options");
+  cmdOptions.add_options()
+    ("help,h", "print this help message")
+    ("version,V", "show program version")
+    ("general,v", po::bool_switch(&options.wantForwarderGeneral), "show general status")
+    ("channels,c", po::bool_switch(&options.wantChannels), "show channels")
+    ("faces,f", po::bool_switch(&options.wantFaces), "show faces")
+    ("fib,b", po::bool_switch(&options.wantFib), "show FIB entries")
+    ("rib,r", po::bool_switch(&options.wantRib), "show RIB routes")
+    ("sc,s", po::bool_switch(&options.wantStrategyChoice), "show strategy choice entries")
+    ("xml,x", "output as XML instead of text (implies -vcfbrs)");
+  po::variables_map vm;
+  try {
+    po::store(po::parse_command_line(argc, argv, cmdOptions), vm);
+  }
+  catch (const po::error& e) {
+    std::cerr << e.what() << "\n";
+    showUsage(std::cerr, cmdOptions);
+    return std::make_tuple(2, options);
+  }
+  po::notify(vm);
+
+  if (vm.count("help") > 0) {
+    showUsage(std::cout, cmdOptions);
+    return std::make_tuple(0, options);
+  }
+  if (vm.count("version") > 0) {
+    std::cout << "nfd-status " << NFD_VERSION_BUILD_STRING << "\n";
+    return std::make_tuple(0, options);
+  }
+
+  if (vm.count("xml") > 0) {
+    options.output = OutputFormat::XML;
+  }
+  if (options.output == OutputFormat::XML ||
+      (!options.wantForwarderGeneral && !options.wantChannels && !options.wantFaces &&
+       !options.wantFib && !options.wantRib && !options.wantStrategyChoice)) {
+    options.wantForwarderGeneral = options.wantChannels = options.wantFaces =
+      options.wantFib = options.wantRib = options.wantStrategyChoice = true;
+  }
+
+  return std::make_tuple(-1, options);
+}
+
+static int
+main(int argc, char** argv)
+{
+  int exitCode = -1;
+  Options options;
+  std::tie(exitCode, options) = parseCommandLine(argc, argv);
+  if (exitCode >= 0) {
+    return exitCode;
+  }
+
+  Face face;
+  KeyChain keyChain;
+  unique_ptr<Validator> validator = make_unique<ndn::ValidatorNull>();
+  CommandOptions ctrlOptions;
+
+  StatusReport report;
+
+  if (options.wantForwarderGeneral) {
+    auto nfdIdCollector = make_unique<NfdIdCollector>(std::move(validator));
+    auto forwarderGeneralModule = make_unique<ForwarderGeneralModule>();
+    forwarderGeneralModule->setNfdIdCollector(*nfdIdCollector);
+    report.sections.push_back(std::move(forwarderGeneralModule));
+    validator = std::move(nfdIdCollector);
+  }
+
+  if (options.wantChannels) {
+    report.sections.push_back(make_unique<ChannelModule>());
+  }
+
+  if (options.wantFaces) {
+    report.sections.push_back(make_unique<FaceModule>());
+  }
+
+  if (options.wantFib) {
+    report.sections.push_back(make_unique<FibModule>());
+  }
+
+  if (options.wantRib) {
+    report.sections.push_back(make_unique<RibModule>());
+  }
+
+  if (options.wantStrategyChoice) {
+    report.sections.push_back(make_unique<StrategyChoiceModule>());
+  }
+
+  uint32_t code = report.collect(face, keyChain, *validator, ctrlOptions);
+  if (code != 0) {
+    // Give a simple error code for end user.
+    // Technical support personnel:
+    // 1. get the exact command from end user
+    // 2. code div 1000000 is zero-based section index
+    // 3. code mod 1000000 is a Controller.fetch error code
+    std::cerr << "Error while collecting status report (" << code << ").\n";
+    return 1;
+  }
+
+  switch (options.output) {
+    case OutputFormat::XML:
+      report.formatXml(std::cout);
+      break;
+    case OutputFormat::TEXT:
+      report.formatText(std::cout);
+      break;
+  }
+  return 0;
+}
+
+} // namespace nfd_status
+} // namespace tools
+} // namespace nfd
+
+int
+main(int argc, char** argv)
+{
+  return nfd::tools::nfd_status::main(argc, argv);
+}