io_context.hpp

//
// io_context.hpp
// ~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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 ASIO_IO_CONTEXT_HPP
#define ASIO_IO_CONTEXT_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)

#include "asio/detail/config.hpp"
#include <cstddef>
#include <stdexcept>
#include <typeinfo>
#include "asio/async_result.hpp"
#include "asio/detail/wrapped_handler.hpp"
#include "asio/error_code.hpp"
#include "asio/execution.hpp"
#include "asio/execution_context.hpp"

#if defined(ASIO_HAS_CHRONO)
# include "asio/detail/chrono.hpp"
#endif // defined(ASIO_HAS_CHRONO)

#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
# include "asio/detail/winsock_init.hpp"
#elif defined(__sun) || defined(__QNX__) || defined(__hpux) || defined(_AIX) \
  || defined(__osf__)
# include "asio/detail/signal_init.hpp"
#endif

#if defined(ASIO_HAS_IOCP)
# include "asio/detail/win_iocp_io_context.hpp"
#else
# include "asio/detail/scheduler.hpp"
#endif

#include "asio/detail/push_options.hpp"

namespace asio {

namespace detail {
#if defined(ASIO_HAS_IOCP)
  typedef win_iocp_io_context io_context_impl;
  class win_iocp_overlapped_ptr;
#else
  typedef scheduler io_context_impl;
#endif

  struct io_context_bits
  {
    ASIO_STATIC_CONSTEXPR(unsigned int, blocking_never = 1);
    ASIO_STATIC_CONSTEXPR(unsigned int, relationship_continuation = 2);
    ASIO_STATIC_CONSTEXPR(unsigned int, outstanding_work_tracked = 4);
  };
} // namespace detail


class io_context
  : public execution_context
{
private:
  typedef detail::io_context_impl impl_type;
#if defined(ASIO_HAS_IOCP)
  friend class detail::win_iocp_overlapped_ptr;
#endif

public:
  template <typename Allocator, unsigned int Bits>
  class basic_executor_type;

  template <typename Allocator, unsigned int Bits>
  friend class basic_executor_type;

  typedef basic_executor_type<std::allocator<void>, 0> executor_type;

#if !defined(ASIO_NO_DEPRECATED)
  class work;
  friend class work;
#endif // !defined(ASIO_NO_DEPRECATED)

  class service;

#if !defined(ASIO_NO_EXTENSIONS) \
  && !defined(ASIO_NO_TS_EXECUTORS)
  class strand;
#endif // !defined(ASIO_NO_EXTENSIONS)
       //   && !defined(ASIO_NO_TS_EXECUTORS)

  typedef std::size_t count_type;

  ASIO_DECL io_context();


  ASIO_DECL explicit io_context(int concurrency_hint);


  ASIO_DECL ~io_context();

  executor_type get_executor() ASIO_NOEXCEPT;


  ASIO_DECL count_type run();

#if !defined(ASIO_NO_DEPRECATED)

  ASIO_DECL count_type run(asio::error_code& ec);
#endif // !defined(ASIO_NO_DEPRECATED)

#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)

  template <typename Rep, typename Period>
  std::size_t run_for(const chrono::duration<Rep, Period>& rel_time);


  template <typename Clock, typename Duration>
  std::size_t run_until(const chrono::time_point<Clock, Duration>& abs_time);
#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)


  ASIO_DECL count_type run_one();

#if !defined(ASIO_NO_DEPRECATED)

  ASIO_DECL count_type run_one(asio::error_code& ec);
#endif // !defined(ASIO_NO_DEPRECATED)

#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)

  template <typename Rep, typename Period>
  std::size_t run_one_for(const chrono::duration<Rep, Period>& rel_time);


  template <typename Clock, typename Duration>
  std::size_t run_one_until(
      const chrono::time_point<Clock, Duration>& abs_time);
#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)


  ASIO_DECL count_type poll();

#if !defined(ASIO_NO_DEPRECATED)

  ASIO_DECL count_type poll(asio::error_code& ec);
#endif // !defined(ASIO_NO_DEPRECATED)


  ASIO_DECL count_type poll_one();

#if !defined(ASIO_NO_DEPRECATED)

  ASIO_DECL count_type poll_one(asio::error_code& ec);
#endif // !defined(ASIO_NO_DEPRECATED)


  ASIO_DECL void stop();


  ASIO_DECL bool stopped() const;


  ASIO_DECL void restart();

#if !defined(ASIO_NO_DEPRECATED)

  void reset();


  template <typename LegacyCompletionHandler>
  ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
  dispatch(ASIO_MOVE_ARG(LegacyCompletionHandler) handler);


  template <typename LegacyCompletionHandler>
  ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
  post(ASIO_MOVE_ARG(LegacyCompletionHandler) handler);


  template <typename Handler>
#if defined(GENERATING_DOCUMENTATION)
  unspecified
#else
  detail::wrapped_handler<io_context&, Handler>
#endif
  wrap(Handler handler);
#endif // !defined(ASIO_NO_DEPRECATED)

private:
  io_context(const io_context&) ASIO_DELETED;
  io_context& operator=(const io_context&) ASIO_DELETED;

#if !defined(ASIO_NO_DEPRECATED)
  struct initiate_dispatch;
  struct initiate_post;
#endif // !defined(ASIO_NO_DEPRECATED)

  // Helper function to add the implementation.
  ASIO_DECL impl_type& add_impl(impl_type* impl);

  // Backwards compatible overload for use with services derived from
  // io_context::service.
  template <typename Service>
  friend Service& use_service(io_context& ioc);

#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
  detail::winsock_init<> init_;
#elif defined(__sun) || defined(__QNX__) || defined(__hpux) || defined(_AIX) \
  || defined(__osf__)
  detail::signal_init<> init_;
#endif

  // The implementation.
  impl_type& impl_;
};

namespace detail {

} // namespace detail

template <typename Allocator, unsigned int Bits>
class io_context::basic_executor_type : detail::io_context_bits
{
public:
  basic_executor_type(
      const basic_executor_type& other) ASIO_NOEXCEPT
    : io_context_(other.io_context_),
      allocator_(other.allocator_),
      bits_(other.bits_)
  {
    if (Bits & outstanding_work_tracked)
      if (io_context_)
        io_context_->impl_.work_started();
  }

#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
  basic_executor_type(basic_executor_type&& other) ASIO_NOEXCEPT
    : io_context_(other.io_context_),
      allocator_(ASIO_MOVE_CAST(Allocator)(other.allocator_)),
      bits_(other.bits_)
  {
    if (Bits & outstanding_work_tracked)
      other.io_context_ = 0;
  }
#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)

  ~basic_executor_type() ASIO_NOEXCEPT
  {
    if (Bits & outstanding_work_tracked)
      if (io_context_)
        io_context_->impl_.work_finished();
  }

  basic_executor_type& operator=(
      const basic_executor_type& other) ASIO_NOEXCEPT;

#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
  basic_executor_type& operator=(
      basic_executor_type&& other) ASIO_NOEXCEPT;
#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)


  ASIO_CONSTEXPR basic_executor_type require(
      execution::blocking_t::possibly_t) const
  {
    return basic_executor_type(io_context_,
        allocator_, bits_ & ~blocking_never);
  }


  ASIO_CONSTEXPR basic_executor_type require(
      execution::blocking_t::never_t) const
  {
    return basic_executor_type(io_context_,
        allocator_, bits_ | blocking_never);
  }


  ASIO_CONSTEXPR basic_executor_type require(
      execution::relationship_t::fork_t) const
  {
    return basic_executor_type(io_context_,
        allocator_, bits_ & ~relationship_continuation);
  }


  ASIO_CONSTEXPR basic_executor_type require(
      execution::relationship_t::continuation_t) const
  {
    return basic_executor_type(io_context_,
        allocator_, bits_ | relationship_continuation);
  }


  ASIO_CONSTEXPR basic_executor_type<Allocator,
      ASIO_UNSPECIFIED(Bits | outstanding_work_tracked)>
  require(execution::outstanding_work_t::tracked_t) const
  {
    return basic_executor_type<Allocator, Bits | outstanding_work_tracked>(
        io_context_, allocator_, bits_);
  }


  ASIO_CONSTEXPR basic_executor_type<Allocator,
      ASIO_UNSPECIFIED(Bits & ~outstanding_work_tracked)>
  require(execution::outstanding_work_t::untracked_t) const
  {
    return basic_executor_type<Allocator, Bits & ~outstanding_work_tracked>(
        io_context_, allocator_, bits_);
  }


  template <typename OtherAllocator>
  ASIO_CONSTEXPR basic_executor_type<OtherAllocator, Bits>
  require(execution::allocator_t<OtherAllocator> a) const
  {
    return basic_executor_type<OtherAllocator, Bits>(
        io_context_, a.value(), bits_);
  }


  ASIO_CONSTEXPR basic_executor_type<std::allocator<void>, Bits>
  require(execution::allocator_t<void>) const
  {
    return basic_executor_type<std::allocator<void>, Bits>(
        io_context_, std::allocator<void>(), bits_);
  }


  static ASIO_CONSTEXPR execution::mapping_t query(
      execution::mapping_t) ASIO_NOEXCEPT
  {
    return execution::mapping.thread;
  }


  io_context& query(execution::context_t) const ASIO_NOEXCEPT
  {
    return *io_context_;
  }


  ASIO_CONSTEXPR execution::blocking_t query(
      execution::blocking_t) const ASIO_NOEXCEPT
  {
    return (bits_ & blocking_never)
      ? execution::blocking_t(execution::blocking.never)
      : execution::blocking_t(execution::blocking.possibly);
  }


  ASIO_CONSTEXPR execution::relationship_t query(
      execution::relationship_t) const ASIO_NOEXCEPT
  {
    return (bits_ & relationship_continuation)
      ? execution::relationship_t(execution::relationship.continuation)
      : execution::relationship_t(execution::relationship.fork);
  }


  static ASIO_CONSTEXPR execution::outstanding_work_t query(
      execution::outstanding_work_t) ASIO_NOEXCEPT
  {
    return (Bits & outstanding_work_tracked)
      ? execution::outstanding_work_t(execution::outstanding_work.tracked)
      : execution::outstanding_work_t(execution::outstanding_work.untracked);
  }


  template <typename OtherAllocator>
  ASIO_CONSTEXPR Allocator query(
      execution::allocator_t<OtherAllocator>) const ASIO_NOEXCEPT
  {
    return allocator_;
  }


  ASIO_CONSTEXPR Allocator query(
      execution::allocator_t<void>) const ASIO_NOEXCEPT
  {
    return allocator_;
  }


  bool running_in_this_thread() const ASIO_NOEXCEPT;


  friend bool operator==(const basic_executor_type& a,
      const basic_executor_type& b) ASIO_NOEXCEPT
  {
    return a.io_context_ == b.io_context_
      && a.allocator_ == b.allocator_
      && a.bits_ == b.bits_;
  }


  friend bool operator!=(const basic_executor_type& a,
      const basic_executor_type& b) ASIO_NOEXCEPT
  {
    return a.io_context_ != b.io_context_
      || a.allocator_ != b.allocator_
      || a.bits_ != b.bits_;
  }


  template <typename Function>
  void execute(ASIO_MOVE_ARG(Function) f) const;

#if !defined(ASIO_NO_TS_EXECUTORS)
  io_context& context() const ASIO_NOEXCEPT;


  void on_work_started() const ASIO_NOEXCEPT;


  void on_work_finished() const ASIO_NOEXCEPT;


  template <typename Function, typename OtherAllocator>
  void dispatch(ASIO_MOVE_ARG(Function) f,
      const OtherAllocator& a) const;


  template <typename Function, typename OtherAllocator>
  void post(ASIO_MOVE_ARG(Function) f,
      const OtherAllocator& a) const;


  template <typename Function, typename OtherAllocator>
  void defer(ASIO_MOVE_ARG(Function) f,
      const OtherAllocator& a) const;
#endif // !defined(ASIO_NO_TS_EXECUTORS)

private:
  friend class io_context;
  template <typename, unsigned int> friend class basic_executor_type;

  // Constructor used by io_context::get_executor().
  explicit basic_executor_type(io_context& i) ASIO_NOEXCEPT
    : io_context_(&i),
      allocator_(),
      bits_(0)
  {
    if (Bits & outstanding_work_tracked)
      io_context_->impl_.work_started();
  }

  // Constructor used by require().
  basic_executor_type(io_context* i,
      const Allocator& a, unsigned int bits) ASIO_NOEXCEPT
    : io_context_(i),
      allocator_(a),
      bits_(bits)
  {
    if (Bits & outstanding_work_tracked)
      if (io_context_)
        io_context_->impl_.work_started();
  }

  // The underlying io_context.
  io_context* io_context_;

  // The allocator used for execution functions.
  Allocator allocator_;

  // The runtime-switched properties of the io_context executor.
  unsigned int bits_;
};

#if !defined(ASIO_NO_DEPRECATED)

class io_context::work
{
public:

  explicit work(asio::io_context& io_context);


  work(const work& other);


  ~work();

  asio::io_context& get_io_context();

private:
  // Prevent assignment.
  void operator=(const work& other);

  // The io_context implementation.
  detail::io_context_impl& io_context_impl_;
};
#endif // !defined(ASIO_NO_DEPRECATED)

class io_context::service
  : public execution_context::service
{
public:
  asio::io_context& get_io_context();

private:
  ASIO_DECL virtual void shutdown();

#if !defined(ASIO_NO_DEPRECATED)
  ASIO_DECL virtual void shutdown_service();
#endif // !defined(ASIO_NO_DEPRECATED)


  ASIO_DECL virtual void notify_fork(
      execution_context::fork_event event);

#if !defined(ASIO_NO_DEPRECATED)

  ASIO_DECL virtual void fork_service(
      execution_context::fork_event event);
#endif // !defined(ASIO_NO_DEPRECATED)

protected:

  ASIO_DECL service(asio::io_context& owner);

  ASIO_DECL virtual ~service();
};

namespace detail {

// Special service base class to keep classes header-file only.
template <typename Type>
class service_base
  : public asio::io_context::service
{
public:
  static asio::detail::service_id<Type> id;

  // Constructor.
  service_base(asio::io_context& io_context)
    : asio::io_context::service(io_context)
  {
  }
};

template <typename Type>
asio::detail::service_id<Type> service_base<Type>::id;

} // namespace detail

#if !defined(GENERATING_DOCUMENTATION)

namespace traits {

#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)

template <typename Allocator, unsigned int Bits>
struct equality_comparable<
    asio::io_context::basic_executor_type<Allocator, Bits>
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
};

#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)

template <typename Allocator, unsigned int Bits, typename Function>
struct execute_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    Function
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef void result_type;
};

#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::blocking_t::possibly_t
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      Allocator, Bits> result_type;
};

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::blocking_t::never_t
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      Allocator, Bits> result_type;
};

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::relationship_t::fork_t
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      Allocator, Bits> result_type;
};

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::relationship_t::continuation_t
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      Allocator, Bits> result_type;
};

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::outstanding_work_t::tracked_t
  > : asio::detail::io_context_bits
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      Allocator, Bits | outstanding_work_tracked> result_type;
};

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::outstanding_work_t::untracked_t
  > : asio::detail::io_context_bits
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      Allocator, Bits & ~outstanding_work_tracked> result_type;
};

template <typename Allocator, unsigned int Bits>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::allocator_t<void>
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      std::allocator<void>, Bits> result_type;
};

template <unsigned int Bits,
    typename Allocator, typename OtherAllocator>
struct require_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::allocator_t<OtherAllocator>
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
  typedef asio::io_context::basic_executor_type<
      OtherAllocator, Bits> result_type;
};

#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)

template <typename Allocator, unsigned int Bits, typename Property>
struct query_static_constexpr_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    Property,
    typename asio::enable_if<
      asio::is_convertible<
        Property,
        asio::execution::outstanding_work_t
      >::value
    >::type
  > : asio::detail::io_context_bits
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef asio::execution::outstanding_work_t result_type;

  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
  {
    return (Bits & outstanding_work_tracked)
      ? execution::outstanding_work_t(execution::outstanding_work.tracked)
      : execution::outstanding_work_t(execution::outstanding_work.untracked);
  }
};

template <typename Allocator, unsigned int Bits, typename Property>
struct query_static_constexpr_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    Property,
    typename asio::enable_if<
      asio::is_convertible<
        Property,
        asio::execution::mapping_t
      >::value
    >::type
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef asio::execution::mapping_t::thread_t result_type;

  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
  {
    return result_type();
  }
};

#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)

#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)

template <typename Allocator, unsigned int Bits, typename Property>
struct query_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    Property,
    typename asio::enable_if<
      asio::is_convertible<
        Property,
        asio::execution::blocking_t
      >::value
    >::type
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef asio::execution::blocking_t result_type;
};

template <typename Allocator, unsigned int Bits, typename Property>
struct query_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    Property,
    typename asio::enable_if<
      asio::is_convertible<
        Property,
        asio::execution::relationship_t
      >::value
    >::type
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef asio::execution::relationship_t result_type;
};

template <typename Allocator, unsigned int Bits>
struct query_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::context_t
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef asio::io_context& result_type;
};

template <typename Allocator, unsigned int Bits>
struct query_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::allocator_t<void>
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef Allocator result_type;
};

template <typename Allocator, unsigned int Bits, typename OtherAllocator>
struct query_member<
    asio::io_context::basic_executor_type<Allocator, Bits>,
    asio::execution::allocator_t<OtherAllocator>
  >
{
  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
  typedef Allocator result_type;
};

#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)

} // namespace traits

#endif // !defined(GENERATING_DOCUMENTATION)

} // namespace asio

#include "asio/detail/pop_options.hpp"

#include "asio/impl/io_context.hpp"
#if defined(ASIO_HEADER_ONLY)
# include "asio/impl/io_context.ipp"
#endif // defined(ASIO_HEADER_ONLY)

// If both io_context.hpp and strand.hpp have been included, automatically
// include the header file needed for the io_context::strand class.
#if !defined(ASIO_NO_EXTENSIONS)
# if defined(ASIO_STRAND_HPP)
#  include "asio/io_context_strand.hpp"
# endif // defined(ASIO_STRAND_HPP)
#endif // !defined(ASIO_NO_EXTENSIONS)

#endif // ASIO_IO_CONTEXT_HPP