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doc/html/boost_asio/example/cpp11/http/server2/connection.cpp

//
// connection.cpp
// ~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2024 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 "connection.hpp"
#include <utility>
#include "request_handler.hpp"

namespace http {
namespace server2 {

connection::connection(boost::asio::ip::tcp::socket socket,
    request_handler& handler)
  : socket_(std::move(socket)),
    request_handler_(handler)
{
}

void connection::start()
{
  do_read();
}

void connection::do_read()
{
  auto self(shared_from_this());
  socket_.async_read_some(boost::asio::buffer(buffer_),
      [this, self](boost::system::error_code ec, std::size_t bytes_transferred)
      {
        if (!ec)
        {
          request_parser::result_type result;
          std::tie(result, std::ignore) = request_parser_.parse(
              request_, buffer_.data(), buffer_.data() + bytes_transferred);

          if (result == request_parser::good)
          {
            request_handler_.handle_request(request_, reply_);
            do_write();
          }
          else if (result == request_parser::bad)
          {
            reply_ = reply::stock_reply(reply::bad_request);
            do_write();
          }
          else
          {
            do_read();
          }
        }

        // If an error occurs then no new asynchronous operations are
        // started. This means that all shared_ptr references to the
        // connection object will disappear and the object will be
        // destroyed automatically after this handler returns. The
        // connection class's destructor closes the socket.
      });
}

void connection::do_write()
{
  auto self(shared_from_this());
  boost::asio::async_write(socket_, reply_.to_buffers(),
      [this, self](boost::system::error_code ec, std::size_t)
      {
        if (!ec)
        {
          // Initiate graceful connection closure.
          boost::system::error_code ignored_ec;
          socket_.shutdown(boost::asio::ip::tcp::socket::shutdown_both,
            ignored_ec);
        }

        // No new asynchronous operations are started. This means that
        // all shared_ptr references to the connection object will
        // disappear and the object will be destroyed automatically after
        // this handler returns. The connection class's destructor closes
        // the socket.
      });
}

} // namespace server2
} // namespace http