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Diffstat (limited to 'lib/asio/basic_deadline_timer.hpp')
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diff --git a/lib/asio/basic_deadline_timer.hpp b/lib/asio/basic_deadline_timer.hpp new file mode 100644 index 0000000..5b20066 --- /dev/null +++ b/lib/asio/basic_deadline_timer.hpp @@ -0,0 +1,628 @@ +// +// basic_deadline_timer.hpp +// ~~~~~~~~~~~~~~~~~~~~~~~~ +// +// Copyright (c) 2003-2018 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_DEADLINE_TIMER_HPP +#define ASIO_BASIC_DEADLINE_TIMER_HPP + +#if defined(_MSC_VER) && (_MSC_VER >= 1200) +# pragma once +#endif // defined(_MSC_VER) && (_MSC_VER >= 1200) + +#include "asio/detail/config.hpp" + +#if defined(ASIO_HAS_BOOST_DATE_TIME) \ + || defined(GENERATING_DOCUMENTATION) + +#include <cstddef> +#include "asio/basic_io_object.hpp" +#include "asio/detail/handler_type_requirements.hpp" +#include "asio/detail/throw_error.hpp" +#include "asio/error.hpp" +#include "asio/time_traits.hpp" + +#if defined(ASIO_ENABLE_OLD_SERVICES) +# include "asio/deadline_timer_service.hpp" +#else // defined(ASIO_ENABLE_OLD_SERVICES) +# include "asio/detail/deadline_timer_service.hpp" +# define ASIO_SVC_T detail::deadline_timer_service<TimeTraits> +#endif // defined(ASIO_ENABLE_OLD_SERVICES) + +#include "asio/detail/push_options.hpp" + +namespace asio { + +/// Provides waitable timer functionality. +/** + * The basic_deadline_timer class template provides the ability to perform a + * blocking or asynchronous wait for a timer to expire. + * + * A deadline timer is always in one of two states: "expired" or "not expired". + * If the wait() or async_wait() function is called on an expired timer, the + * wait operation will complete immediately. + * + * Most applications will use the asio::deadline_timer typedef. + * + * @par Thread Safety + * @e Distinct @e objects: Safe.@n + * @e Shared @e objects: Unsafe. + * + * @par Examples + * Performing a blocking wait: + * @code + * // Construct a timer without setting an expiry time. + * asio::deadline_timer timer(io_context); + * + * // Set an expiry time relative to now. + * timer.expires_from_now(boost::posix_time::seconds(5)); + * + * // Wait for the timer to expire. + * timer.wait(); + * @endcode + * + * @par + * Performing an asynchronous wait: + * @code + * void handler(const asio::error_code& error) + * { + * if (!error) + * { + * // Timer expired. + * } + * } + * + * ... + * + * // Construct a timer with an absolute expiry time. + * asio::deadline_timer timer(io_context, + * boost::posix_time::time_from_string("2005-12-07 23:59:59.000")); + * + * // Start an asynchronous wait. + * timer.async_wait(handler); + * @endcode + * + * @par Changing an active deadline_timer's expiry time + * + * Changing the expiry time of a timer while there are pending asynchronous + * waits causes those wait operations to be cancelled. To ensure that the action + * associated with the timer is performed only once, use something like this: + * used: + * + * @code + * void on_some_event() + * { + * if (my_timer.expires_from_now(seconds(5)) > 0) + * { + * // We managed to cancel the timer. Start new asynchronous wait. + * my_timer.async_wait(on_timeout); + * } + * else + * { + * // Too late, timer has already expired! + * } + * } + * + * void on_timeout(const asio::error_code& e) + * { + * if (e != asio::error::operation_aborted) + * { + * // Timer was not cancelled, take necessary action. + * } + * } + * @endcode + * + * @li The asio::basic_deadline_timer::expires_from_now() function + * cancels any pending asynchronous waits, and returns the number of + * asynchronous waits that were cancelled. If it returns 0 then you were too + * late and the wait handler has already been executed, or will soon be + * executed. If it returns 1 then the wait handler was successfully cancelled. + * + * @li If a wait handler is cancelled, the asio::error_code passed to + * it contains the value asio::error::operation_aborted. + */ +template <typename Time, + typename TimeTraits = asio::time_traits<Time> + ASIO_SVC_TPARAM_DEF2(= deadline_timer_service<Time, TimeTraits>)> +class basic_deadline_timer + : ASIO_SVC_ACCESS basic_io_object<ASIO_SVC_T> +{ +public: + /// The type of the executor associated with the object. + typedef io_context::executor_type executor_type; + + /// The time traits type. + typedef TimeTraits traits_type; + + /// The time type. + typedef typename traits_type::time_type time_type; + + /// The duration type. + typedef typename traits_type::duration_type duration_type; + + /// Constructor. + /** + * This constructor creates a timer without setting an expiry time. The + * expires_at() or expires_from_now() functions must be called to set an + * expiry time before the timer can be waited on. + * + * @param io_context The io_context object that the timer will use to dispatch + * handlers for any asynchronous operations performed on the timer. + */ + explicit basic_deadline_timer(asio::io_context& io_context) + : basic_io_object<ASIO_SVC_T>(io_context) + { + } + + /// Constructor to set a particular expiry time as an absolute time. + /** + * This constructor creates a timer and sets the expiry time. + * + * @param io_context The io_context object that the timer will use to dispatch + * handlers for any asynchronous operations performed on the timer. + * + * @param expiry_time The expiry time to be used for the timer, expressed + * as an absolute time. + */ + basic_deadline_timer(asio::io_context& io_context, + const time_type& expiry_time) + : basic_io_object<ASIO_SVC_T>(io_context) + { + asio::error_code ec; + this->get_service().expires_at(this->get_implementation(), expiry_time, ec); + asio::detail::throw_error(ec, "expires_at"); + } + + /// Constructor to set a particular expiry time relative to now. + /** + * This constructor creates a timer and sets the expiry time. + * + * @param io_context The io_context object that the timer will use to dispatch + * handlers for any asynchronous operations performed on the timer. + * + * @param expiry_time The expiry time to be used for the timer, relative to + * now. + */ + basic_deadline_timer(asio::io_context& io_context, + const duration_type& expiry_time) + : basic_io_object<ASIO_SVC_T>(io_context) + { + asio::error_code ec; + this->get_service().expires_from_now( + this->get_implementation(), expiry_time, ec); + asio::detail::throw_error(ec, "expires_from_now"); + } + +#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION) + /// Move-construct a basic_deadline_timer from another. + /** + * This constructor moves a timer from one object to another. + * + * @param other The other basic_deadline_timer object from which the move will + * occur. + * + * @note Following the move, the moved-from object is in the same state as if + * constructed using the @c basic_deadline_timer(io_context&) constructor. + */ + basic_deadline_timer(basic_deadline_timer&& other) + : basic_io_object<ASIO_SVC_T>(std::move(other)) + { + } + + /// Move-assign a basic_deadline_timer from another. + /** + * This assignment operator moves a timer from one object to another. Cancels + * any outstanding asynchronous operations associated with the target object. + * + * @param other The other basic_deadline_timer object from which the move will + * occur. + * + * @note Following the move, the moved-from object is in the same state as if + * constructed using the @c basic_deadline_timer(io_context&) constructor. + */ + basic_deadline_timer& operator=(basic_deadline_timer&& other) + { + basic_io_object<ASIO_SVC_T>::operator=(std::move(other)); + return *this; + } +#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION) + + /// Destroys the timer. + /** + * This function destroys the timer, cancelling any outstanding asynchronous + * wait operations associated with the timer as if by calling @c cancel. + */ + ~basic_deadline_timer() + { + } + +#if defined(ASIO_ENABLE_OLD_SERVICES) + // These functions are provided by basic_io_object<>. +#else // defined(ASIO_ENABLE_OLD_SERVICES) +#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 basic_io_object<ASIO_SVC_T>::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 basic_io_object<ASIO_SVC_T>::get_io_service(); + } +#endif // !defined(ASIO_NO_DEPRECATED) + + /// Get the executor associated with the object. + executor_type get_executor() ASIO_NOEXCEPT + { + return basic_io_object<ASIO_SVC_T>::get_executor(); + } +#endif // defined(ASIO_ENABLE_OLD_SERVICES) + + /// Cancel any asynchronous operations that are waiting on the timer. + /** + * This function forces the completion of any pending asynchronous wait + * operations against the timer. The handler for each cancelled operation will + * be invoked with the asio::error::operation_aborted error code. + * + * Cancelling the timer does not change the expiry time. + * + * @return The number of asynchronous operations that were cancelled. + * + * @throws asio::system_error Thrown on failure. + * + * @note If the timer has already expired when cancel() is called, then the + * handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t cancel() + { + asio::error_code ec; + std::size_t s = this->get_service().cancel(this->get_implementation(), ec); + asio::detail::throw_error(ec, "cancel"); + return s; + } + + /// Cancel any asynchronous operations that are waiting on the timer. + /** + * This function forces the completion of any pending asynchronous wait + * operations against the timer. The handler for each cancelled operation will + * be invoked with the asio::error::operation_aborted error code. + * + * Cancelling the timer does not change the expiry time. + * + * @param ec Set to indicate what error occurred, if any. + * + * @return The number of asynchronous operations that were cancelled. + * + * @note If the timer has already expired when cancel() is called, then the + * handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t cancel(asio::error_code& ec) + { + return this->get_service().cancel(this->get_implementation(), ec); + } + + /// Cancels one asynchronous operation that is waiting on the timer. + /** + * This function forces the completion of one pending asynchronous wait + * operation against the timer. Handlers are cancelled in FIFO order. The + * handler for the cancelled operation will be invoked with the + * asio::error::operation_aborted error code. + * + * Cancelling the timer does not change the expiry time. + * + * @return The number of asynchronous operations that were cancelled. That is, + * either 0 or 1. + * + * @throws asio::system_error Thrown on failure. + * + * @note If the timer has already expired when cancel_one() is called, then + * the handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t cancel_one() + { + asio::error_code ec; + std::size_t s = this->get_service().cancel_one( + this->get_implementation(), ec); + asio::detail::throw_error(ec, "cancel_one"); + return s; + } + + /// Cancels one asynchronous operation that is waiting on the timer. + /** + * This function forces the completion of one pending asynchronous wait + * operation against the timer. Handlers are cancelled in FIFO order. The + * handler for the cancelled operation will be invoked with the + * asio::error::operation_aborted error code. + * + * Cancelling the timer does not change the expiry time. + * + * @param ec Set to indicate what error occurred, if any. + * + * @return The number of asynchronous operations that were cancelled. That is, + * either 0 or 1. + * + * @note If the timer has already expired when cancel_one() is called, then + * the handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t cancel_one(asio::error_code& ec) + { + return this->get_service().cancel_one(this->get_implementation(), ec); + } + + /// Get the timer's expiry time as an absolute time. + /** + * This function may be used to obtain the timer's current expiry time. + * Whether the timer has expired or not does not affect this value. + */ + time_type expires_at() const + { + return this->get_service().expires_at(this->get_implementation()); + } + + /// Set the timer's expiry time as an absolute time. + /** + * This function sets the expiry time. Any pending asynchronous wait + * operations will be cancelled. The handler for each cancelled operation will + * be invoked with the asio::error::operation_aborted error code. + * + * @param expiry_time The expiry time to be used for the timer. + * + * @return The number of asynchronous operations that were cancelled. + * + * @throws asio::system_error Thrown on failure. + * + * @note If the timer has already expired when expires_at() is called, then + * the handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t expires_at(const time_type& expiry_time) + { + asio::error_code ec; + std::size_t s = this->get_service().expires_at( + this->get_implementation(), expiry_time, ec); + asio::detail::throw_error(ec, "expires_at"); + return s; + } + + /// Set the timer's expiry time as an absolute time. + /** + * This function sets the expiry time. Any pending asynchronous wait + * operations will be cancelled. The handler for each cancelled operation will + * be invoked with the asio::error::operation_aborted error code. + * + * @param expiry_time The expiry time to be used for the timer. + * + * @param ec Set to indicate what error occurred, if any. + * + * @return The number of asynchronous operations that were cancelled. + * + * @note If the timer has already expired when expires_at() is called, then + * the handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t expires_at(const time_type& expiry_time, + asio::error_code& ec) + { + return this->get_service().expires_at( + this->get_implementation(), expiry_time, ec); + } + + /// Get the timer's expiry time relative to now. + /** + * This function may be used to obtain the timer's current expiry time. + * Whether the timer has expired or not does not affect this value. + */ + duration_type expires_from_now() const + { + return this->get_service().expires_from_now(this->get_implementation()); + } + + /// Set the timer's expiry time relative to now. + /** + * This function sets the expiry time. Any pending asynchronous wait + * operations will be cancelled. The handler for each cancelled operation will + * be invoked with the asio::error::operation_aborted error code. + * + * @param expiry_time The expiry time to be used for the timer. + * + * @return The number of asynchronous operations that were cancelled. + * + * @throws asio::system_error Thrown on failure. + * + * @note If the timer has already expired when expires_from_now() is called, + * then the handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t expires_from_now(const duration_type& expiry_time) + { + asio::error_code ec; + std::size_t s = this->get_service().expires_from_now( + this->get_implementation(), expiry_time, ec); + asio::detail::throw_error(ec, "expires_from_now"); + return s; + } + + /// Set the timer's expiry time relative to now. + /** + * This function sets the expiry time. Any pending asynchronous wait + * operations will be cancelled. The handler for each cancelled operation will + * be invoked with the asio::error::operation_aborted error code. + * + * @param expiry_time The expiry time to be used for the timer. + * + * @param ec Set to indicate what error occurred, if any. + * + * @return The number of asynchronous operations that were cancelled. + * + * @note If the timer has already expired when expires_from_now() is called, + * then the handlers for asynchronous wait operations will: + * + * @li have already been invoked; or + * + * @li have been queued for invocation in the near future. + * + * These handlers can no longer be cancelled, and therefore are passed an + * error code that indicates the successful completion of the wait operation. + */ + std::size_t expires_from_now(const duration_type& expiry_time, + asio::error_code& ec) + { + return this->get_service().expires_from_now( + this->get_implementation(), expiry_time, ec); + } + + /// Perform a blocking wait on the timer. + /** + * This function is used to wait for the timer to expire. This function + * blocks and does not return until the timer has expired. + * + * @throws asio::system_error Thrown on failure. + */ + void wait() + { + asio::error_code ec; + this->get_service().wait(this->get_implementation(), ec); + asio::detail::throw_error(ec, "wait"); + } + + /// Perform a blocking wait on the timer. + /** + * This function is used to wait for the timer to expire. This function + * blocks and does not return until the timer has expired. + * + * @param ec Set to indicate what error occurred, if any. + */ + void wait(asio::error_code& ec) + { + this->get_service().wait(this->get_implementation(), ec); + } + + /// Start an asynchronous wait on the timer. + /** + * This function may be used to initiate an asynchronous wait against the + * timer. It always returns immediately. + * + * For each call to async_wait(), the supplied handler will be called exactly + * once. The handler will be called when: + * + * @li The timer has expired. + * + * @li The timer was cancelled, in which case the handler is passed the error + * code asio::error::operation_aborted. + * + * @param handler The handler to be called when the timer expires. Copies + * will be made of the handler as required. The function signature of the + * handler must be: + * @code void handler( + * const asio::error_code& error // Result of operation. + * ); @endcode + * Regardless of whether the asynchronous operation completes immediately or + * not, the handler will not be invoked from within this function. Invocation + * of the handler will be performed in a manner equivalent to using + * asio::io_context::post(). + */ + template <typename WaitHandler> + ASIO_INITFN_RESULT_TYPE(WaitHandler, + void (asio::error_code)) + async_wait(ASIO_MOVE_ARG(WaitHandler) handler) + { + // If you get an error on the following line it means that your handler does + // not meet the documented type requirements for a WaitHandler. + ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check; + +#if defined(ASIO_ENABLE_OLD_SERVICES) + return this->get_service().async_wait(this->get_implementation(), + ASIO_MOVE_CAST(WaitHandler)(handler)); +#else // defined(ASIO_ENABLE_OLD_SERVICES) + async_completion<WaitHandler, + void (asio::error_code)> init(handler); + + this->get_service().async_wait(this->get_implementation(), + init.completion_handler); + + return init.result.get(); +#endif // defined(ASIO_ENABLE_OLD_SERVICES) + } +}; + +} // namespace asio + +#include "asio/detail/pop_options.hpp" + +#if !defined(ASIO_ENABLE_OLD_SERVICES) +# undef ASIO_SVC_T +#endif // !defined(ASIO_ENABLE_OLD_SERVICES) + +#endif // defined(ASIO_HAS_BOOST_DATE_TIME) + // || defined(GENERATING_DOCUMENTATION) + +#endif // ASIO_BASIC_DEADLINE_TIMER_HPP |