add basic http server (using boost.asio example)

Change-Id: I02bbc161ec7f89ade999b92ed99ef71fec83af32
diff --git a/server/server.cpp b/server/server.cpp
new file mode 100644
index 0000000..5fcc5d9
--- /dev/null
+++ b/server/server.cpp
@@ -0,0 +1,94 @@
+//
+// server.cpp
+// ~~~~~~~~~~
+//
+// Copyright (c) 2003-2012 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include "server.hpp"
+#include <boost/bind.hpp>
+#include <signal.h>
+
+namespace http {
+namespace server {
+
+server::server(const std::string& address, const std::string& port,
+    const std::string& doc_root)
+  : io_service_(),
+    signals_(io_service_),
+    acceptor_(io_service_),
+    connection_manager_(),
+    new_connection_(),
+    request_handler_(doc_root)
+{
+  // Register to handle the signals that indicate when the server should exit.
+  // It is safe to register for the same signal multiple times in a program,
+  // provided all registration for the specified signal is made through Asio.
+  signals_.add(SIGINT);
+  signals_.add(SIGTERM);
+#if defined(SIGQUIT)
+  signals_.add(SIGQUIT);
+#endif // defined(SIGQUIT)
+  signals_.async_wait(boost::bind(&server::handle_stop, this));
+
+  // Open the acceptor with the option to reuse the address (i.e. SO_REUSEADDR).
+  boost::asio::ip::tcp::resolver resolver(io_service_);
+  boost::asio::ip::tcp::resolver::query query(address, port);
+  boost::asio::ip::tcp::endpoint endpoint = *resolver.resolve(query);
+  acceptor_.open(endpoint.protocol());
+  acceptor_.set_option(boost::asio::ip::tcp::acceptor::reuse_address(true));
+  acceptor_.bind(endpoint);
+  acceptor_.listen();
+
+  start_accept();
+}
+
+void server::run()
+{
+  // The io_service::run() call will block until all asynchronous operations
+  // have finished. While the server is running, there is always at least one
+  // asynchronous operation outstanding: the asynchronous accept call waiting
+  // for new incoming connections.
+  io_service_.run();
+}
+
+void server::start_accept()
+{
+  new_connection_.reset(new connection(io_service_,
+        connection_manager_, request_handler_));
+  acceptor_.async_accept(new_connection_->socket(),
+      boost::bind(&server::handle_accept, this,
+        boost::asio::placeholders::error));
+}
+
+void server::handle_accept(const boost::system::error_code& e)
+{
+  // Check whether the server was stopped by a signal before this completion
+  // handler had a chance to run.
+  if (!acceptor_.is_open())
+  {
+    return;
+  }
+
+  if (!e)
+  {
+    connection_manager_.start(new_connection_);
+  }
+
+  start_accept();
+}
+
+void server::handle_stop()
+{
+  // The server is stopped by cancelling all outstanding asynchronous
+  // operations. Once all operations have finished the io_service::run() call
+  // will exit.
+  acceptor_.close();
+  connection_manager_.stop_all();
+}
+
+} // namespace server
+} // namespace http