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- //
- // basic_io_object.hpp
- // ~~~~~~~~~~~~~~~~~~~
- //
- // Copyright (c) 2003-2019 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_BASIC_IO_OBJECT_HPP
- #define ASIO_BASIC_IO_OBJECT_HPP
-
- #if defined(_MSC_VER) && (_MSC_VER >= 1200)
- # pragma once
- #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
- #include "asio/detail/config.hpp"
- #include "asio/io_context.hpp"
-
- #include "asio/detail/push_options.hpp"
-
- namespace asio {
-
- #if defined(ASIO_HAS_MOVE)
- namespace detail
- {
- // Type trait used to determine whether a service supports move.
- template <typename IoObjectService>
- class service_has_move
- {
- private:
- typedef IoObjectService service_type;
- typedef typename service_type::implementation_type implementation_type;
-
- template <typename T, typename U>
- static auto asio_service_has_move_eval(T* t, U* u)
- -> decltype(t->move_construct(*u, *u), char());
- static char (&asio_service_has_move_eval(...))[2];
-
- public:
- static const bool value =
- sizeof(asio_service_has_move_eval(
- static_cast<service_type*>(0),
- static_cast<implementation_type*>(0))) == 1;
- };
- }
- #endif // defined(ASIO_HAS_MOVE)
-
- /// Base class for all I/O objects.
- /**
- * @note All I/O objects are non-copyable. However, when using C++0x, certain
- * I/O objects do support move construction and move assignment.
- */
- #if !defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
- template <typename IoObjectService>
- #else
- template <typename IoObjectService,
- bool Movable = detail::service_has_move<IoObjectService>::value>
- #endif
- class basic_io_object
- {
- public:
- /// The type of the service that will be used to provide I/O operations.
- typedef IoObjectService service_type;
-
- /// The underlying implementation type of I/O object.
- typedef typename service_type::implementation_type implementation_type;
-
- #if !defined(ASIO_NO_DEPRECATED)
- /// (Deprecated: Use get_executor().) Get the io_context associated with the
- /// object.
- /**
- * This function may be used to obtain the io_context object that the I/O
- * object uses to dispatch handlers for asynchronous operations.
- *
- * @return A reference to the io_context object that the I/O object will use
- * to dispatch handlers. Ownership is not transferred to the caller.
- */
- asio::io_context& get_io_context()
- {
- return service_.get_io_context();
- }
-
- /// (Deprecated: Use get_executor().) Get the io_context associated with the
- /// object.
- /**
- * This function may be used to obtain the io_context object that the I/O
- * object uses to dispatch handlers for asynchronous operations.
- *
- * @return A reference to the io_context object that the I/O object will use
- * to dispatch handlers. Ownership is not transferred to the caller.
- */
- asio::io_context& get_io_service()
- {
- return service_.get_io_context();
- }
- #endif // !defined(ASIO_NO_DEPRECATED)
-
- /// The type of the executor associated with the object.
- typedef asio::io_context::executor_type executor_type;
-
- /// Get the executor associated with the object.
- executor_type get_executor() ASIO_NOEXCEPT
- {
- return service_.get_io_context().get_executor();
- }
-
- protected:
- /// Construct a basic_io_object.
- /**
- * Performs:
- * @code get_service().construct(get_implementation()); @endcode
- */
- explicit basic_io_object(asio::io_context& io_context)
- : service_(asio::use_service<IoObjectService>(io_context))
- {
- service_.construct(implementation_);
- }
-
- #if defined(GENERATING_DOCUMENTATION)
- /// Move-construct a basic_io_object.
- /**
- * Performs:
- * @code get_service().move_construct(
- * get_implementation(), other.get_implementation()); @endcode
- *
- * @note Available only for services that support movability,
- */
- basic_io_object(basic_io_object&& other);
-
- /// Move-assign a basic_io_object.
- /**
- * Performs:
- * @code get_service().move_assign(get_implementation(),
- * other.get_service(), other.get_implementation()); @endcode
- *
- * @note Available only for services that support movability,
- */
- basic_io_object& operator=(basic_io_object&& other);
-
- /// Perform a converting move-construction of a basic_io_object.
- template <typename IoObjectService1>
- basic_io_object(IoObjectService1& other_service,
- typename IoObjectService1::implementation_type& other_implementation);
- #endif // defined(GENERATING_DOCUMENTATION)
-
- /// Protected destructor to prevent deletion through this type.
- /**
- * Performs:
- * @code get_service().destroy(get_implementation()); @endcode
- */
- ~basic_io_object()
- {
- service_.destroy(implementation_);
- }
-
- /// Get the service associated with the I/O object.
- service_type& get_service()
- {
- return service_;
- }
-
- /// Get the service associated with the I/O object.
- const service_type& get_service() const
- {
- return service_;
- }
-
- /// Get the underlying implementation of the I/O object.
- implementation_type& get_implementation()
- {
- return implementation_;
- }
-
- /// Get the underlying implementation of the I/O object.
- const implementation_type& get_implementation() const
- {
- return implementation_;
- }
-
- private:
- basic_io_object(const basic_io_object&);
- basic_io_object& operator=(const basic_io_object&);
-
- // The service associated with the I/O object.
- service_type& service_;
-
- /// The underlying implementation of the I/O object.
- implementation_type implementation_;
- };
-
- #if defined(ASIO_HAS_MOVE)
- // Specialisation for movable objects.
- template <typename IoObjectService>
- class basic_io_object<IoObjectService, true>
- {
- public:
- typedef IoObjectService service_type;
- typedef typename service_type::implementation_type implementation_type;
-
- #if !defined(ASIO_NO_DEPRECATED)
- asio::io_context& get_io_context()
- {
- return service_->get_io_context();
- }
-
- asio::io_context& get_io_service()
- {
- return service_->get_io_context();
- }
- #endif // !defined(ASIO_NO_DEPRECATED)
-
- typedef asio::io_context::executor_type executor_type;
-
- executor_type get_executor() ASIO_NOEXCEPT
- {
- return service_->get_io_context().get_executor();
- }
-
- protected:
- explicit basic_io_object(asio::io_context& io_context)
- : service_(&asio::use_service<IoObjectService>(io_context))
- {
- service_->construct(implementation_);
- }
-
- basic_io_object(basic_io_object&& other)
- : service_(&other.get_service())
- {
- service_->move_construct(implementation_, other.implementation_);
- }
-
- template <typename IoObjectService1>
- basic_io_object(IoObjectService1& other_service,
- typename IoObjectService1::implementation_type& other_implementation)
- : service_(&asio::use_service<IoObjectService>(
- other_service.get_io_context()))
- {
- service_->converting_move_construct(implementation_,
- other_service, other_implementation);
- }
-
- ~basic_io_object()
- {
- service_->destroy(implementation_);
- }
-
- basic_io_object& operator=(basic_io_object&& other)
- {
- service_->move_assign(implementation_,
- *other.service_, other.implementation_);
- service_ = other.service_;
- return *this;
- }
-
- service_type& get_service()
- {
- return *service_;
- }
-
- const service_type& get_service() const
- {
- return *service_;
- }
-
- implementation_type& get_implementation()
- {
- return implementation_;
- }
-
- const implementation_type& get_implementation() const
- {
- return implementation_;
- }
-
- private:
- basic_io_object(const basic_io_object&);
- void operator=(const basic_io_object&);
-
- IoObjectService* service_;
- implementation_type implementation_;
- };
- #endif // defined(ASIO_HAS_MOVE)
-
- } // namespace asio
-
- #include "asio/detail/pop_options.hpp"
-
- #endif // ASIO_BASIC_IO_OBJECT_HPP
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