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773 lines
28 KiB
C++
773 lines
28 KiB
C++
//
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// io_service.hpp
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// ~~~~~~~~~~~~~~
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//
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// Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com)
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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#ifndef BOOST_ASIO_IO_SERVICE_HPP
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#define BOOST_ASIO_IO_SERVICE_HPP
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#if defined(_MSC_VER) && (_MSC_VER >= 1200)
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# pragma once
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#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
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#include <boost/asio/detail/config.hpp>
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#include <cstddef>
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#include <stdexcept>
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#include <typeinfo>
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#include <boost/asio/async_result.hpp>
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#include <boost/asio/detail/noncopyable.hpp>
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#include <boost/asio/detail/wrapped_handler.hpp>
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#include <boost/system/error_code.hpp>
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#if defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
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# include <boost/asio/detail/winsock_init.hpp>
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#elif defined(__sun) || defined(__QNX__) || defined(__hpux) || defined(_AIX) \
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|| defined(__osf__)
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# include <boost/asio/detail/signal_init.hpp>
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#endif
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#include <boost/asio/detail/push_options.hpp>
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namespace boost {
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namespace asio {
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class io_service;
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template <typename Service> Service& use_service(io_service& ios);
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template <typename Service> void add_service(io_service& ios, Service* svc);
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template <typename Service> bool has_service(io_service& ios);
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namespace detail {
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#if defined(BOOST_ASIO_HAS_IOCP)
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typedef class win_iocp_io_service io_service_impl;
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class win_iocp_overlapped_ptr;
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#else
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typedef class task_io_service io_service_impl;
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#endif
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class service_registry;
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} // namespace detail
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/// Provides core I/O functionality.
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/**
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* The io_service class provides the core I/O functionality for users of the
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* asynchronous I/O objects, including:
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*
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* @li boost::asio::ip::tcp::socket
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* @li boost::asio::ip::tcp::acceptor
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* @li boost::asio::ip::udp::socket
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* @li boost::asio::deadline_timer.
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*
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* The io_service class also includes facilities intended for developers of
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* custom asynchronous services.
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*
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* @par Thread Safety
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* @e Distinct @e objects: Safe.@n
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* @e Shared @e objects: Safe, with the specific exceptions of the reset() and
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* notify_fork() functions. Calling reset() while there are unfinished run(),
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* run_one(), poll() or poll_one() calls results in undefined behaviour. The
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* notify_fork() function should not be called while any io_service function,
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* or any function on an I/O object that is associated with the io_service, is
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* being called in another thread.
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*
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* @par Concepts:
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* Dispatcher.
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*
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* @par Synchronous and asynchronous operations
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*
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* Synchronous operations on I/O objects implicitly run the io_service object
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* for an individual operation. The io_service functions run(), run_one(),
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* poll() or poll_one() must be called for the io_service to perform
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* asynchronous operations on behalf of a C++ program. Notification that an
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* asynchronous operation has completed is delivered by invocation of the
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* associated handler. Handlers are invoked only by a thread that is currently
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* calling any overload of run(), run_one(), poll() or poll_one() for the
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* io_service.
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*
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* @par Effect of exceptions thrown from handlers
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*
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* If an exception is thrown from a handler, the exception is allowed to
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* propagate through the throwing thread's invocation of run(), run_one(),
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* poll() or poll_one(). No other threads that are calling any of these
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* functions are affected. It is then the responsibility of the application to
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* catch the exception.
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*
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* After the exception has been caught, the run(), run_one(), poll() or
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* poll_one() call may be restarted @em without the need for an intervening
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* call to reset(). This allows the thread to rejoin the io_service object's
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* thread pool without impacting any other threads in the pool.
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*
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* For example:
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*
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* @code
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* boost::asio::io_service io_service;
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* ...
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* for (;;)
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* {
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* try
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* {
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* io_service.run();
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* break; // run() exited normally
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* }
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* catch (my_exception& e)
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* {
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* // Deal with exception as appropriate.
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* }
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* }
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* @endcode
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*
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* @par Stopping the io_service from running out of work
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*
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* Some applications may need to prevent an io_service object's run() call from
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* returning when there is no more work to do. For example, the io_service may
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* be being run in a background thread that is launched prior to the
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* application's asynchronous operations. The run() call may be kept running by
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* creating an object of type boost::asio::io_service::work:
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*
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* @code boost::asio::io_service io_service;
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* boost::asio::io_service::work work(io_service);
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* ... @endcode
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*
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* To effect a shutdown, the application will then need to call the io_service
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* object's stop() member function. This will cause the io_service run() call
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* to return as soon as possible, abandoning unfinished operations and without
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* permitting ready handlers to be dispatched.
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*
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* Alternatively, if the application requires that all operations and handlers
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* be allowed to finish normally, the work object may be explicitly destroyed.
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*
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* @code boost::asio::io_service io_service;
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* auto_ptr<boost::asio::io_service::work> work(
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* new boost::asio::io_service::work(io_service));
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* ...
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* work.reset(); // Allow run() to exit. @endcode
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*
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* @par The io_service class and I/O services
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*
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* Class io_service implements an extensible, type-safe, polymorphic set of I/O
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* services, indexed by service type. An object of class io_service must be
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* initialised before I/O objects such as sockets, resolvers and timers can be
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* used. These I/O objects are distinguished by having constructors that accept
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* an @c io_service& parameter.
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*
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* I/O services exist to manage the logical interface to the operating system on
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* behalf of the I/O objects. In particular, there are resources that are shared
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* across a class of I/O objects. For example, timers may be implemented in
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* terms of a single timer queue. The I/O services manage these shared
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* resources.
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*
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* Access to the services of an io_service is via three function templates,
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* use_service(), add_service() and has_service().
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*
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* In a call to @c use_service<Service>(), the type argument chooses a service,
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* making available all members of the named type. If @c Service is not present
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* in an io_service, an object of type @c Service is created and added to the
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* io_service. A C++ program can check if an io_service implements a
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* particular service with the function template @c has_service<Service>().
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*
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* Service objects may be explicitly added to an io_service using the function
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* template @c add_service<Service>(). If the @c Service is already present, the
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* service_already_exists exception is thrown. If the owner of the service is
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* not the same object as the io_service parameter, the invalid_service_owner
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* exception is thrown.
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*
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* Once a service reference is obtained from an io_service object by calling
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* use_service(), that reference remains usable as long as the owning io_service
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* object exists.
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*
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* All I/O service implementations have io_service::service as a public base
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* class. Custom I/O services may be implemented by deriving from this class and
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* then added to an io_service using the facilities described above.
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*/
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class io_service
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: private noncopyable
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{
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private:
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typedef detail::io_service_impl impl_type;
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#if defined(BOOST_ASIO_HAS_IOCP)
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friend class detail::win_iocp_overlapped_ptr;
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#endif
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public:
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class work;
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friend class work;
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class id;
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class service;
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class strand;
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/// Constructor.
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BOOST_ASIO_DECL io_service();
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/// Constructor.
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/**
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* Construct with a hint about the required level of concurrency.
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*
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* @param concurrency_hint A suggestion to the implementation on how many
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* threads it should allow to run simultaneously.
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*/
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BOOST_ASIO_DECL explicit io_service(std::size_t concurrency_hint);
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/// Destructor.
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/**
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* On destruction, the io_service performs the following sequence of
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* operations:
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*
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* @li For each service object @c svc in the io_service set, in reverse order
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* of the beginning of service object lifetime, performs
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* @c svc->shutdown_service().
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*
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* @li Uninvoked handler objects that were scheduled for deferred invocation
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* on the io_service, or any associated strand, are destroyed.
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*
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* @li For each service object @c svc in the io_service set, in reverse order
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* of the beginning of service object lifetime, performs
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* <tt>delete static_cast<io_service::service*>(svc)</tt>.
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*
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* @note The destruction sequence described above permits programs to
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* simplify their resource management by using @c shared_ptr<>. Where an
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* object's lifetime is tied to the lifetime of a connection (or some other
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* sequence of asynchronous operations), a @c shared_ptr to the object would
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* be bound into the handlers for all asynchronous operations associated with
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* it. This works as follows:
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*
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* @li When a single connection ends, all associated asynchronous operations
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* complete. The corresponding handler objects are destroyed, and all
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* @c shared_ptr references to the objects are destroyed.
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*
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* @li To shut down the whole program, the io_service function stop() is
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* called to terminate any run() calls as soon as possible. The io_service
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* destructor defined above destroys all handlers, causing all @c shared_ptr
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* references to all connection objects to be destroyed.
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*/
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BOOST_ASIO_DECL ~io_service();
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/// Run the io_service object's event processing loop.
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/**
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* The run() function blocks until all work has finished and there are no
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* more handlers to be dispatched, or until the io_service has been stopped.
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*
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* Multiple threads may call the run() function to set up a pool of threads
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* from which the io_service may execute handlers. All threads that are
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* waiting in the pool are equivalent and the io_service may choose any one
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* of them to invoke a handler.
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*
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* A normal exit from the run() function implies that the io_service object
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* is stopped (the stopped() function returns @c true). Subsequent calls to
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* run(), run_one(), poll() or poll_one() will return immediately unless there
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* is a prior call to reset().
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*
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* @return The number of handlers that were executed.
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*
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* @throws boost::system::system_error Thrown on failure.
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*
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* @note The run() function must not be called from a thread that is currently
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* calling one of run(), run_one(), poll() or poll_one() on the same
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* io_service object.
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*
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* The poll() function may also be used to dispatch ready handlers, but
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* without blocking.
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*/
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BOOST_ASIO_DECL std::size_t run();
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/// Run the io_service object's event processing loop.
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/**
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* The run() function blocks until all work has finished and there are no
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* more handlers to be dispatched, or until the io_service has been stopped.
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*
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* Multiple threads may call the run() function to set up a pool of threads
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* from which the io_service may execute handlers. All threads that are
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* waiting in the pool are equivalent and the io_service may choose any one
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* of them to invoke a handler.
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*
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* A normal exit from the run() function implies that the io_service object
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* is stopped (the stopped() function returns @c true). Subsequent calls to
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* run(), run_one(), poll() or poll_one() will return immediately unless there
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* is a prior call to reset().
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*
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* @param ec Set to indicate what error occurred, if any.
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*
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* @return The number of handlers that were executed.
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*
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* @note The run() function must not be called from a thread that is currently
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* calling one of run(), run_one(), poll() or poll_one() on the same
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* io_service object.
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*
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* The poll() function may also be used to dispatch ready handlers, but
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* without blocking.
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*/
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BOOST_ASIO_DECL std::size_t run(boost::system::error_code& ec);
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/// Run the io_service object's event processing loop to execute at most one
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/// handler.
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/**
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* The run_one() function blocks until one handler has been dispatched, or
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* until the io_service has been stopped.
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*
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* @return The number of handlers that were executed. A zero return value
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* implies that the io_service object is stopped (the stopped() function
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* returns @c true). Subsequent calls to run(), run_one(), poll() or
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* poll_one() will return immediately unless there is a prior call to
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* reset().
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*
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* @throws boost::system::system_error Thrown on failure.
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*/
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BOOST_ASIO_DECL std::size_t run_one();
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/// Run the io_service object's event processing loop to execute at most one
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/// handler.
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/**
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* The run_one() function blocks until one handler has been dispatched, or
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* until the io_service has been stopped.
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*
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* @return The number of handlers that were executed. A zero return value
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* implies that the io_service object is stopped (the stopped() function
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* returns @c true). Subsequent calls to run(), run_one(), poll() or
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* poll_one() will return immediately unless there is a prior call to
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* reset().
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*
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* @return The number of handlers that were executed.
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*/
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BOOST_ASIO_DECL std::size_t run_one(boost::system::error_code& ec);
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/// Run the io_service object's event processing loop to execute ready
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/// handlers.
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/**
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* The poll() function runs handlers that are ready to run, without blocking,
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* until the io_service has been stopped or there are no more ready handlers.
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*
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* @return The number of handlers that were executed.
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*
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* @throws boost::system::system_error Thrown on failure.
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*/
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BOOST_ASIO_DECL std::size_t poll();
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/// Run the io_service object's event processing loop to execute ready
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/// handlers.
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/**
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* The poll() function runs handlers that are ready to run, without blocking,
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* until the io_service has been stopped or there are no more ready handlers.
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*
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* @param ec Set to indicate what error occurred, if any.
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*
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* @return The number of handlers that were executed.
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*/
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BOOST_ASIO_DECL std::size_t poll(boost::system::error_code& ec);
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/// Run the io_service object's event processing loop to execute one ready
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/// handler.
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/**
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* The poll_one() function runs at most one handler that is ready to run,
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* without blocking.
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*
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* @return The number of handlers that were executed.
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*
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* @throws boost::system::system_error Thrown on failure.
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*/
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BOOST_ASIO_DECL std::size_t poll_one();
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/// Run the io_service object's event processing loop to execute one ready
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/// handler.
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/**
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* The poll_one() function runs at most one handler that is ready to run,
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* without blocking.
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*
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* @param ec Set to indicate what error occurred, if any.
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*
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* @return The number of handlers that were executed.
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*/
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BOOST_ASIO_DECL std::size_t poll_one(boost::system::error_code& ec);
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/// Stop the io_service object's event processing loop.
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/**
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* This function does not block, but instead simply signals the io_service to
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* stop. All invocations of its run() or run_one() member functions should
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* return as soon as possible. Subsequent calls to run(), run_one(), poll()
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* or poll_one() will return immediately until reset() is called.
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*/
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BOOST_ASIO_DECL void stop();
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/// Determine whether the io_service object has been stopped.
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/**
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* This function is used to determine whether an io_service object has been
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* stopped, either through an explicit call to stop(), or due to running out
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* of work. When an io_service object is stopped, calls to run(), run_one(),
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* poll() or poll_one() will return immediately without invoking any
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* handlers.
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*
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* @return @c true if the io_service object is stopped, otherwise @c false.
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*/
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BOOST_ASIO_DECL bool stopped() const;
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/// Reset the io_service in preparation for a subsequent run() invocation.
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/**
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* This function must be called prior to any second or later set of
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* invocations of the run(), run_one(), poll() or poll_one() functions when a
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* previous invocation of these functions returned due to the io_service
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* being stopped or running out of work. After a call to reset(), the
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* io_service object's stopped() function will return @c false.
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*
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* This function must not be called while there are any unfinished calls to
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* the run(), run_one(), poll() or poll_one() functions.
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*/
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BOOST_ASIO_DECL void reset();
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/// Request the io_service to invoke the given handler.
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/**
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* This function is used to ask the io_service to execute the given handler.
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*
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* The io_service guarantees that the handler will only be called in a thread
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* in which the run(), run_one(), poll() or poll_one() member functions is
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* currently being invoked. The handler may be executed inside this function
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* if the guarantee can be met.
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*
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* @param handler The handler to be called. The io_service will make
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* a copy of the handler object as required. The function signature of the
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* handler must be: @code void handler(); @endcode
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*
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* @note This function throws an exception only if:
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*
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* @li the handler's @c asio_handler_allocate function; or
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*
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* @li the handler's copy constructor
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*
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* throws an exception.
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*/
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template <typename CompletionHandler>
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BOOST_ASIO_INITFN_RESULT_TYPE(CompletionHandler, void ())
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dispatch(BOOST_ASIO_MOVE_ARG(CompletionHandler) handler);
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/// Request the io_service to invoke the given handler and return immediately.
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/**
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* This function is used to ask the io_service to execute the given handler,
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* but without allowing the io_service to call the handler from inside this
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* function.
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*
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* The io_service guarantees that the handler will only be called in a thread
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* in which the run(), run_one(), poll() or poll_one() member functions is
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* currently being invoked.
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*
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* @param handler The handler to be called. The io_service will make
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* a copy of the handler object as required. The function signature of the
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* handler must be: @code void handler(); @endcode
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*
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* @note This function throws an exception only if:
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*
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* @li the handler's @c asio_handler_allocate function; or
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*
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* @li the handler's copy constructor
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*
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* throws an exception.
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*/
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template <typename CompletionHandler>
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BOOST_ASIO_INITFN_RESULT_TYPE(CompletionHandler, void ())
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post(BOOST_ASIO_MOVE_ARG(CompletionHandler) handler);
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/// Create a new handler that automatically dispatches the wrapped handler
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/// on the io_service.
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/**
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* This function is used to create a new handler function object that, when
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* invoked, will automatically pass the wrapped handler to the io_service
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* object's dispatch function.
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*
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* @param handler The handler to be wrapped. The io_service will make a copy
|
|
* of the handler object as required. The function signature of the handler
|
|
* must be: @code void handler(A1 a1, ... An an); @endcode
|
|
*
|
|
* @return A function object that, when invoked, passes the wrapped handler to
|
|
* the io_service object's dispatch function. Given a function object with the
|
|
* signature:
|
|
* @code R f(A1 a1, ... An an); @endcode
|
|
* If this function object is passed to the wrap function like so:
|
|
* @code io_service.wrap(f); @endcode
|
|
* then the return value is a function object with the signature
|
|
* @code void g(A1 a1, ... An an); @endcode
|
|
* that, when invoked, executes code equivalent to:
|
|
* @code io_service.dispatch(boost::bind(f, a1, ... an)); @endcode
|
|
*/
|
|
template <typename Handler>
|
|
#if defined(GENERATING_DOCUMENTATION)
|
|
unspecified
|
|
#else
|
|
detail::wrapped_handler<io_service&, Handler>
|
|
#endif
|
|
wrap(Handler handler);
|
|
|
|
/// Fork-related event notifications.
|
|
enum fork_event
|
|
{
|
|
/// Notify the io_service that the process is about to fork.
|
|
fork_prepare,
|
|
|
|
/// Notify the io_service that the process has forked and is the parent.
|
|
fork_parent,
|
|
|
|
/// Notify the io_service that the process has forked and is the child.
|
|
fork_child
|
|
};
|
|
|
|
/// Notify the io_service of a fork-related event.
|
|
/**
|
|
* This function is used to inform the io_service that the process is about
|
|
* to fork, or has just forked. This allows the io_service, and the services
|
|
* it contains, to perform any necessary housekeeping to ensure correct
|
|
* operation following a fork.
|
|
*
|
|
* This function must not be called while any other io_service function, or
|
|
* any function on an I/O object associated with the io_service, is being
|
|
* called in another thread. It is, however, safe to call this function from
|
|
* within a completion handler, provided no other thread is accessing the
|
|
* io_service.
|
|
*
|
|
* @param event A fork-related event.
|
|
*
|
|
* @throws boost::system::system_error Thrown on failure. If the notification
|
|
* fails the io_service object should no longer be used and should be
|
|
* destroyed.
|
|
*
|
|
* @par Example
|
|
* The following code illustrates how to incorporate the notify_fork()
|
|
* function:
|
|
* @code my_io_service.notify_fork(boost::asio::io_service::fork_prepare);
|
|
* if (fork() == 0)
|
|
* {
|
|
* // This is the child process.
|
|
* my_io_service.notify_fork(boost::asio::io_service::fork_child);
|
|
* }
|
|
* else
|
|
* {
|
|
* // This is the parent process.
|
|
* my_io_service.notify_fork(boost::asio::io_service::fork_parent);
|
|
* } @endcode
|
|
*
|
|
* @note For each service object @c svc in the io_service set, performs
|
|
* <tt>svc->fork_service();</tt>. When processing the fork_prepare event,
|
|
* services are visited in reverse order of the beginning of service object
|
|
* lifetime. Otherwise, services are visited in order of the beginning of
|
|
* service object lifetime.
|
|
*/
|
|
BOOST_ASIO_DECL void notify_fork(boost::asio::io_service::fork_event event);
|
|
|
|
/// Obtain the service object corresponding to the given type.
|
|
/**
|
|
* This function is used to locate a service object that corresponds to
|
|
* the given service type. If there is no existing implementation of the
|
|
* service, then the io_service will create a new instance of the service.
|
|
*
|
|
* @param ios The io_service object that owns the service.
|
|
*
|
|
* @return The service interface implementing the specified service type.
|
|
* Ownership of the service interface is not transferred to the caller.
|
|
*/
|
|
template <typename Service>
|
|
friend Service& use_service(io_service& ios);
|
|
|
|
/// Add a service object to the io_service.
|
|
/**
|
|
* This function is used to add a service to the io_service.
|
|
*
|
|
* @param ios The io_service object that owns the service.
|
|
*
|
|
* @param svc The service object. On success, ownership of the service object
|
|
* is transferred to the io_service. When the io_service object is destroyed,
|
|
* it will destroy the service object by performing:
|
|
* @code delete static_cast<io_service::service*>(svc) @endcode
|
|
*
|
|
* @throws boost::asio::service_already_exists Thrown if a service of the
|
|
* given type is already present in the io_service.
|
|
*
|
|
* @throws boost::asio::invalid_service_owner Thrown if the service's owning
|
|
* io_service is not the io_service object specified by the ios parameter.
|
|
*/
|
|
template <typename Service>
|
|
friend void add_service(io_service& ios, Service* svc);
|
|
|
|
/// Determine if an io_service contains a specified service type.
|
|
/**
|
|
* This function is used to determine whether the io_service contains a
|
|
* service object corresponding to the given service type.
|
|
*
|
|
* @param ios The io_service object that owns the service.
|
|
*
|
|
* @return A boolean indicating whether the io_service contains the service.
|
|
*/
|
|
template <typename Service>
|
|
friend bool has_service(io_service& ios);
|
|
|
|
private:
|
|
#if defined(BOOST_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 service registry.
|
|
boost::asio::detail::service_registry* service_registry_;
|
|
|
|
// The implementation.
|
|
impl_type& impl_;
|
|
};
|
|
|
|
/// Class to inform the io_service when it has work to do.
|
|
/**
|
|
* The work class is used to inform the io_service when work starts and
|
|
* finishes. This ensures that the io_service object's run() function will not
|
|
* exit while work is underway, and that it does exit when there is no
|
|
* unfinished work remaining.
|
|
*
|
|
* The work class is copy-constructible so that it may be used as a data member
|
|
* in a handler class. It is not assignable.
|
|
*/
|
|
class io_service::work
|
|
{
|
|
public:
|
|
/// Constructor notifies the io_service that work is starting.
|
|
/**
|
|
* The constructor is used to inform the io_service that some work has begun.
|
|
* This ensures that the io_service object's run() function will not exit
|
|
* while the work is underway.
|
|
*/
|
|
explicit work(boost::asio::io_service& io_service);
|
|
|
|
/// Copy constructor notifies the io_service that work is starting.
|
|
/**
|
|
* The constructor is used to inform the io_service that some work has begun.
|
|
* This ensures that the io_service object's run() function will not exit
|
|
* while the work is underway.
|
|
*/
|
|
work(const work& other);
|
|
|
|
/// Destructor notifies the io_service that the work is complete.
|
|
/**
|
|
* The destructor is used to inform the io_service that some work has
|
|
* finished. Once the count of unfinished work reaches zero, the io_service
|
|
* object's run() function is permitted to exit.
|
|
*/
|
|
~work();
|
|
|
|
/// Get the io_service associated with the work.
|
|
boost::asio::io_service& get_io_service();
|
|
|
|
private:
|
|
// Prevent assignment.
|
|
void operator=(const work& other);
|
|
|
|
// The io_service implementation.
|
|
detail::io_service_impl& io_service_impl_;
|
|
};
|
|
|
|
/// Class used to uniquely identify a service.
|
|
class io_service::id
|
|
: private noncopyable
|
|
{
|
|
public:
|
|
/// Constructor.
|
|
id() {}
|
|
};
|
|
|
|
/// Base class for all io_service services.
|
|
class io_service::service
|
|
: private noncopyable
|
|
{
|
|
public:
|
|
/// Get the io_service object that owns the service.
|
|
boost::asio::io_service& get_io_service();
|
|
|
|
protected:
|
|
/// Constructor.
|
|
/**
|
|
* @param owner The io_service object that owns the service.
|
|
*/
|
|
BOOST_ASIO_DECL service(boost::asio::io_service& owner);
|
|
|
|
/// Destructor.
|
|
BOOST_ASIO_DECL virtual ~service();
|
|
|
|
private:
|
|
/// Destroy all user-defined handler objects owned by the service.
|
|
virtual void shutdown_service() = 0;
|
|
|
|
/// Handle notification of a fork-related event to perform any necessary
|
|
/// housekeeping.
|
|
/**
|
|
* This function is not a pure virtual so that services only have to
|
|
* implement it if necessary. The default implementation does nothing.
|
|
*/
|
|
BOOST_ASIO_DECL virtual void fork_service(
|
|
boost::asio::io_service::fork_event event);
|
|
|
|
friend class boost::asio::detail::service_registry;
|
|
struct key
|
|
{
|
|
key() : type_info_(0), id_(0) {}
|
|
const std::type_info* type_info_;
|
|
const boost::asio::io_service::id* id_;
|
|
} key_;
|
|
|
|
boost::asio::io_service& owner_;
|
|
service* next_;
|
|
};
|
|
|
|
/// Exception thrown when trying to add a duplicate service to an io_service.
|
|
class service_already_exists
|
|
: public std::logic_error
|
|
{
|
|
public:
|
|
BOOST_ASIO_DECL service_already_exists();
|
|
};
|
|
|
|
/// Exception thrown when trying to add a service object to an io_service where
|
|
/// the service has a different owner.
|
|
class invalid_service_owner
|
|
: public std::logic_error
|
|
{
|
|
public:
|
|
BOOST_ASIO_DECL invalid_service_owner();
|
|
};
|
|
|
|
namespace detail {
|
|
|
|
// Special derived service id type to keep classes header-file only.
|
|
template <typename Type>
|
|
class service_id
|
|
: public boost::asio::io_service::id
|
|
{
|
|
};
|
|
|
|
// Special service base class to keep classes header-file only.
|
|
template <typename Type>
|
|
class service_base
|
|
: public boost::asio::io_service::service
|
|
{
|
|
public:
|
|
static boost::asio::detail::service_id<Type> id;
|
|
|
|
// Constructor.
|
|
service_base(boost::asio::io_service& io_service)
|
|
: boost::asio::io_service::service(io_service)
|
|
{
|
|
}
|
|
};
|
|
|
|
template <typename Type>
|
|
boost::asio::detail::service_id<Type> service_base<Type>::id;
|
|
|
|
} // namespace detail
|
|
} // namespace asio
|
|
} // namespace boost
|
|
|
|
#include <boost/asio/detail/pop_options.hpp>
|
|
|
|
#include <boost/asio/impl/io_service.hpp>
|
|
#if defined(BOOST_ASIO_HEADER_ONLY)
|
|
# include <boost/asio/impl/io_service.ipp>
|
|
#endif // defined(BOOST_ASIO_HEADER_ONLY)
|
|
|
|
#endif // BOOST_ASIO_IO_SERVICE_HPP
|