text: //
  // detail/impl/win_iocp_io_context.hpp
  // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2022 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)
  //
  
  #ifndef BOOST_ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_HPP
  #define BOOST_ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include <boost/asio/detail/config.hpp>
  
  #if defined(BOOST_ASIO_HAS_IOCP)
  
  #include <boost/asio/detail/completion_handler.hpp>
  #include <boost/asio/detail/fenced_block.hpp>
  #include <boost/asio/detail/handler_alloc_helpers.hpp>
  #include <boost/asio/detail/handler_invoke_helpers.hpp>
  #include <boost/asio/detail/memory.hpp>
  
  #include <boost/asio/detail/push_options.hpp>
  
  namespace boost {
  namespace asio {
  namespace detail {
  
  template <typename Time_Traits>
  void win_iocp_io_context::add_timer_queue(
      timer_queue<Time_Traits>& queue)
  {
    do_add_timer_queue(queue);
  }
  
  template <typename Time_Traits>
  void win_iocp_io_context::remove_timer_queue(
      timer_queue<Time_Traits>& queue)
  {
    do_remove_timer_queue(queue);
  }
  
  template <typename Time_Traits>
  void win_iocp_io_context::schedule_timer(timer_queue<Time_Traits>& queue,
      const typename Time_Traits::time_type& time,
      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
  {
    // If the service has been shut down we silently discard the timer.
    if (::InterlockedExchangeAdd(&shutdown_, 0) != 0)
    {
      post_immediate_completion(op, false);
      return;
    }
  
    mutex::scoped_lock lock(dispatch_mutex_);
  
    bool earliest = queue.enqueue_timer(time, timer, op);
    work_started();
    if (earliest)
      update_timeout();
  }
  
  template <typename Time_Traits>
  std::size_t win_iocp_io_context::cancel_timer(timer_queue<Time_Traits>& queue,
      typename timer_queue<Time_Traits>::per_timer_data& timer,
      std::size_t max_cancelled)
  {
    // If the service has been shut down we silently ignore the cancellation.
    if (::InterlockedExchangeAdd(&shutdown_, 0) != 0)
      return 0;
  
    mutex::scoped_lock lock(dispatch_mutex_);
    op_queue<win_iocp_operation> ops;
    std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
    lock.unlock();
    post_deferred_completions(ops);
    return n;
  }
  
  template <typename Time_Traits>
  void win_iocp_io_context::cancel_timer_by_key(timer_queue<Time_Traits>& queue,
      typename timer_queue<Time_Traits>::per_timer_data* timer,
      void* cancellation_key)
  {
    // If the service has been shut down we silently ignore the cancellation.
    if (::InterlockedExchangeAdd(&shutdown_, 0) != 0)
      return;
  
    mutex::scoped_lock lock(dispatch_mutex_);
    op_queue<win_iocp_operation> ops;
    queue.cancel_timer_by_key(timer, ops, cancellation_key);
    lock.unlock();
    post_deferred_completions(ops);
  }
  
  template <typename Time_Traits>
  void win_iocp_io_context::move_timer(timer_queue<Time_Traits>& queue,
      typename timer_queue<Time_Traits>::per_timer_data& to,
      typename timer_queue<Time_Traits>::per_timer_data& from)
  {
    boost::asio::detail::mutex::scoped_lock lock(dispatch_mutex_);
    op_queue<operation> ops;
    queue.cancel_timer(to, ops);
    queue.move_timer(to, from);
    lock.unlock();
    post_deferred_completions(ops);
  }
  
  } // namespace detail
  } // namespace asio
  } // namespace boost
  
  #include <boost/asio/detail/pop_options.hpp>
  
  #endif // defined(BOOST_ASIO_HAS_IOCP)
  
  #endif // BOOST_ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_HPP
  