| // |
| // detail/epoll_reactor.hpp |
| // ~~~~~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2016 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_DETAIL_EPOLL_REACTOR_HPP |
| #define ASIO_DETAIL_EPOLL_REACTOR_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_EPOLL) |
| |
| #include "asio/detail/atomic_count.hpp" |
| #include "asio/detail/conditionally_enabled_mutex.hpp" |
| #include "asio/detail/limits.hpp" |
| #include "asio/detail/object_pool.hpp" |
| #include "asio/detail/op_queue.hpp" |
| #include "asio/detail/reactor_op.hpp" |
| #include "asio/detail/select_interrupter.hpp" |
| #include "asio/detail/socket_types.hpp" |
| #include "asio/detail/timer_queue_base.hpp" |
| #include "asio/detail/timer_queue_set.hpp" |
| #include "asio/detail/wait_op.hpp" |
| #include "asio/execution_context.hpp" |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| namespace detail { |
| |
| class epoll_reactor |
| : public execution_context_service_base<epoll_reactor> |
| { |
| private: |
| // The mutex type used by this reactor. |
| typedef conditionally_enabled_mutex mutex; |
| |
| 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 try_speculative_[max_ops]; |
| bool shutdown_; |
| |
| ASIO_DECL descriptor_state(bool locking); |
| void set_ready_events(uint32_t events) { task_result_ = events; } |
| ASIO_DECL operation* perform_io(uint32_t events); |
| ASIO_DECL static void do_complete( |
| void* owner, operation* base, |
| const asio::error_code& ec, std::size_t bytes_transferred); |
| }; |
| |
| // Per-descriptor data. |
| typedef descriptor_state* per_descriptor_data; |
| |
| // Constructor. |
| ASIO_DECL epoll_reactor(asio::execution_context& ctx); |
| |
| // Destructor. |
| ASIO_DECL ~epoll_reactor(); |
| |
| // Destroy all user-defined handler objects owned by the service. |
| ASIO_DECL void shutdown(); |
| |
| // Recreate internal descriptors following a fork. |
| ASIO_DECL void notify_fork( |
| asio::execution_context::fork_event fork_ev); |
| |
| // Initialise the task. |
| ASIO_DECL void init_task(); |
| |
| // Register a socket with the reactor. Returns 0 on success, system error |
| // code on failure. |
| 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. |
| 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. |
| 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) |
| { |
| scheduler_.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. |
| 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. |
| 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. |
| ASIO_DECL void deregister_descriptor(socket_type descriptor, |
| per_descriptor_data& descriptor_data, bool closing); |
| |
| // Remote the descriptor's registration from the reactor. |
| 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)()); |
| |
| // Move the timer operations associated with the given timer. |
| template <typename Time_Traits> |
| void move_timer(timer_queue<Time_Traits>& queue, |
| typename timer_queue<Time_Traits>::per_timer_data& target, |
| typename timer_queue<Time_Traits>::per_timer_data& source); |
| |
| // Run epoll once until interrupted or events are ready to be dispatched. |
| ASIO_DECL void run(long usec, op_queue<operation>& ops); |
| |
| // Interrupt the select loop. |
| 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. |
| ASIO_DECL static int do_epoll_create(); |
| |
| // Create the timerfd file descriptor. Does not throw. |
| ASIO_DECL static int do_timerfd_create(); |
| |
| // Allocate a new descriptor state object. |
| ASIO_DECL descriptor_state* allocate_descriptor_state(); |
| |
| // Free an existing descriptor state object. |
| ASIO_DECL void free_descriptor_state(descriptor_state* s); |
| |
| // Helper function to add a new timer queue. |
| ASIO_DECL void do_add_timer_queue(timer_queue_base& queue); |
| |
| // Helper function to remove a timer queue. |
| ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue); |
| |
| // Called to recalculate and update the timeout. |
| 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. |
| ASIO_DECL int get_timeout(int msec); |
| |
| #if defined(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. |
| ASIO_DECL int get_timeout(itimerspec& ts); |
| #endif // defined(ASIO_HAS_TIMERFD) |
| |
| // The scheduler implementation used to post completions. |
| scheduler& scheduler_; |
| |
| // 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 |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #include "asio/detail/impl/epoll_reactor.hpp" |
| #if defined(ASIO_HEADER_ONLY) |
| # include "asio/detail/impl/epoll_reactor.ipp" |
| #endif // defined(ASIO_HEADER_ONLY) |
| |
| #endif // defined(ASIO_HAS_EPOLL) |
| |
| #endif // ASIO_DETAIL_EPOLL_REACTOR_HPP |