// // detail/epoll_reactor.hpp // ~~~~~~~~~~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2014 Christopher M. Kohlhoff (chris at kohlhoff dot com) // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) // #ifndef BOOST_ASIO_DETAIL_EPOLL_REACTOR_HPP #define BOOST_ASIO_DETAIL_EPOLL_REACTOR_HPP #if defined(_MSC_VER) && (_MSC_VER >= 1200) # pragma once #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) #include <boost/asio/detail/config.hpp> #if defined(BOOST_ASIO_HAS_EPOLL) #include <boost/asio/io_service.hpp> #include <boost/asio/detail/atomic_count.hpp> #include <boost/asio/detail/limits.hpp> #include <boost/asio/detail/mutex.hpp> #include <boost/asio/detail/object_pool.hpp> #include <boost/asio/detail/op_queue.hpp> #include <boost/asio/detail/reactor_op.hpp> #include <boost/asio/detail/select_interrupter.hpp> #include <boost/asio/detail/socket_types.hpp> #include <boost/asio/detail/timer_queue_base.hpp> #include <boost/asio/detail/timer_queue_set.hpp> #include <boost/asio/detail/wait_op.hpp> #include <boost/asio/detail/push_options.hpp> namespace boost { namespace asio { namespace detail { class epoll_reactor : public boost::asio::detail::service_base<epoll_reactor> { public: enum op_types { read_op = 0, write_op = 1, connect_op = 1, except_op = 2, max_ops = 3 }; // Per-descriptor queues. class descriptor_state : operation { friend class epoll_reactor; friend class object_pool_access; descriptor_state* next_; descriptor_state* prev_; mutex mutex_; epoll_reactor* reactor_; int descriptor_; uint32_t registered_events_; op_queue<reactor_op> op_queue_[max_ops]; bool shutdown_; BOOST_ASIO_DECL descriptor_state(); void set_ready_events(uint32_t events) { task_result_ = events; } BOOST_ASIO_DECL operation* perform_io(uint32_t events); BOOST_ASIO_DECL static void do_complete( io_service_impl* owner, operation* base, const boost::system::error_code& ec, std::size_t bytes_transferred); }; // Per-descriptor data. typedef descriptor_state* per_descriptor_data; // Constructor. BOOST_ASIO_DECL epoll_reactor(boost::asio::io_service& io_service); // Destructor. BOOST_ASIO_DECL ~epoll_reactor(); // Destroy all user-defined handler objects owned by the service. BOOST_ASIO_DECL void shutdown_service(); // Recreate internal descriptors following a fork. BOOST_ASIO_DECL void fork_service( boost::asio::io_service::fork_event fork_ev); // Initialise the task. BOOST_ASIO_DECL void init_task(); // Register a socket with the reactor. Returns 0 on success, system error // code on failure. BOOST_ASIO_DECL int register_descriptor(socket_type descriptor, per_descriptor_data& descriptor_data); // Register a descriptor with an associated single operation. Returns 0 on // success, system error code on failure. BOOST_ASIO_DECL int register_internal_descriptor( int op_type, socket_type descriptor, per_descriptor_data& descriptor_data, reactor_op* op); // Move descriptor registration from one descriptor_data object to another. BOOST_ASIO_DECL void move_descriptor(socket_type descriptor, per_descriptor_data& target_descriptor_data, per_descriptor_data& source_descriptor_data); // Post a reactor operation for immediate completion. void post_immediate_completion(reactor_op* op, bool is_continuation) { io_service_.post_immediate_completion(op, is_continuation); } // Start a new operation. The reactor operation will be performed when the // given descriptor is flagged as ready, or an error has occurred. BOOST_ASIO_DECL void start_op(int op_type, socket_type descriptor, per_descriptor_data& descriptor_data, reactor_op* op, bool is_continuation, bool allow_speculative); // Cancel all operations associated with the given descriptor. The // handlers associated with the descriptor will be invoked with the // operation_aborted error. BOOST_ASIO_DECL void cancel_ops(socket_type descriptor, per_descriptor_data& descriptor_data); // Cancel any operations that are running against the descriptor and remove // its registration from the reactor. BOOST_ASIO_DECL void deregister_descriptor(socket_type descriptor, per_descriptor_data& descriptor_data, bool closing); // Remote the descriptor's registration from the reactor. BOOST_ASIO_DECL void deregister_internal_descriptor( socket_type descriptor, per_descriptor_data& descriptor_data); // Add a new timer queue to the reactor. template <typename Time_Traits> void add_timer_queue(timer_queue<Time_Traits>& timer_queue); // Remove a timer queue from the reactor. template <typename Time_Traits> void remove_timer_queue(timer_queue<Time_Traits>& timer_queue); // Schedule a new operation in the given timer queue to expire at the // specified absolute time. template <typename Time_Traits> void schedule_timer(timer_queue<Time_Traits>& queue, const typename Time_Traits::time_type& time, typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op); // Cancel the timer operations associated with the given token. Returns the // number of operations that have been posted or dispatched. template <typename Time_Traits> std::size_t cancel_timer(timer_queue<Time_Traits>& queue, typename timer_queue<Time_Traits>::per_timer_data& timer, std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)()); // Run epoll once until interrupted or events are ready to be dispatched. BOOST_ASIO_DECL void run(bool block, op_queue<operation>& ops); // Interrupt the select loop. BOOST_ASIO_DECL void interrupt(); private: // The hint to pass to epoll_create to size its data structures. enum { epoll_size = 20000 }; // Create the epoll file descriptor. Throws an exception if the descriptor // cannot be created. BOOST_ASIO_DECL static int do_epoll_create(); // Create the timerfd file descriptor. Does not throw. BOOST_ASIO_DECL static int do_timerfd_create(); // Allocate a new descriptor state object. BOOST_ASIO_DECL descriptor_state* allocate_descriptor_state(); // Free an existing descriptor state object. BOOST_ASIO_DECL void free_descriptor_state(descriptor_state* s); // Helper function to add a new timer queue. BOOST_ASIO_DECL void do_add_timer_queue(timer_queue_base& queue); // Helper function to remove a timer queue. BOOST_ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue); // Called to recalculate and update the timeout. BOOST_ASIO_DECL void update_timeout(); // Get the timeout value for the epoll_wait call. The timeout value is // returned as a number of milliseconds. A return value of -1 indicates // that epoll_wait should block indefinitely. BOOST_ASIO_DECL int get_timeout(); #if defined(BOOST_ASIO_HAS_TIMERFD) // Get the timeout value for the timer descriptor. The return value is the // flag argument to be used when calling timerfd_settime. BOOST_ASIO_DECL int get_timeout(itimerspec& ts); #endif // defined(BOOST_ASIO_HAS_TIMERFD) // The io_service implementation used to post completions. io_service_impl& io_service_; // Mutex to protect access to internal data. mutex mutex_; // The interrupter is used to break a blocking epoll_wait call. select_interrupter interrupter_; // The epoll file descriptor. int epoll_fd_; // The timer file descriptor. int timer_fd_; // The timer queues. timer_queue_set timer_queues_; // Whether the service has been shut down. bool shutdown_; // Mutex to protect access to the registered descriptors. mutex registered_descriptors_mutex_; // Keep track of all registered descriptors. object_pool<descriptor_state> registered_descriptors_; // Helper class to do post-perform_io cleanup. struct perform_io_cleanup_on_block_exit; friend struct perform_io_cleanup_on_block_exit; }; } // namespace detail } // namespace asio } // namespace boost #include <boost/asio/detail/pop_options.hpp> #include <boost/asio/detail/impl/epoll_reactor.hpp> #if defined(BOOST_ASIO_HEADER_ONLY) # include <boost/asio/detail/impl/epoll_reactor.ipp> #endif // defined(BOOST_ASIO_HEADER_ONLY) #endif // defined(BOOST_ASIO_HAS_EPOLL) #endif // BOOST_ASIO_DETAIL_EPOLL_REACTOR_HPP