| // |
| // detail/resolver_service_base.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_DETAIL_RESOLVER_SERVICE_BASE_HPP |
| #define ASIO_DETAIL_RESOLVER_SERVICE_BASE_HPP |
| |
| #if defined(_MSC_VER) && (_MSC_VER >= 1200) |
| # pragma once |
| #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) |
| |
| #include "asio/detail/config.hpp" |
| #include "asio/error.hpp" |
| #include "asio/execution_context.hpp" |
| #include "asio/detail/mutex.hpp" |
| #include "asio/detail/noncopyable.hpp" |
| #include "asio/detail/resolve_op.hpp" |
| #include "asio/detail/socket_ops.hpp" |
| #include "asio/detail/socket_types.hpp" |
| #include "asio/detail/scoped_ptr.hpp" |
| #include "asio/detail/thread.hpp" |
| |
| #if defined(ASIO_HAS_IOCP) |
| # include "asio/detail/win_iocp_io_context.hpp" |
| #else // defined(ASIO_HAS_IOCP) |
| # include "asio/detail/scheduler.hpp" |
| #endif // defined(ASIO_HAS_IOCP) |
| |
| #include "asio/detail/push_options.hpp" |
| |
| namespace asio { |
| namespace detail { |
| |
| class resolver_service_base |
| { |
| public: |
| // The implementation type of the resolver. A cancellation token is used to |
| // indicate to the background thread that the operation has been cancelled. |
| typedef socket_ops::shared_cancel_token_type implementation_type; |
| |
| // Constructor. |
| ASIO_DECL resolver_service_base(execution_context& context); |
| |
| // Destructor. |
| ASIO_DECL ~resolver_service_base(); |
| |
| // Destroy all user-defined handler objects owned by the service. |
| ASIO_DECL void base_shutdown(); |
| |
| // Perform any fork-related housekeeping. |
| ASIO_DECL void base_notify_fork( |
| execution_context::fork_event fork_ev); |
| |
| // Construct a new resolver implementation. |
| ASIO_DECL void construct(implementation_type& impl); |
| |
| // Destroy a resolver implementation. |
| ASIO_DECL void destroy(implementation_type&); |
| |
| // Move-construct a new resolver implementation. |
| ASIO_DECL void move_construct(implementation_type& impl, |
| implementation_type& other_impl); |
| |
| // Move-assign from another resolver implementation. |
| ASIO_DECL void move_assign(implementation_type& impl, |
| resolver_service_base& other_service, |
| implementation_type& other_impl); |
| |
| // Cancel pending asynchronous operations. |
| ASIO_DECL void cancel(implementation_type& impl); |
| |
| protected: |
| // Helper function to start an asynchronous resolve operation. |
| ASIO_DECL void start_resolve_op(resolve_op* op); |
| |
| #if !defined(ASIO_WINDOWS_RUNTIME) |
| // Helper class to perform exception-safe cleanup of addrinfo objects. |
| class auto_addrinfo |
| : private asio::detail::noncopyable |
| { |
| public: |
| explicit auto_addrinfo(asio::detail::addrinfo_type* ai) |
| : ai_(ai) |
| { |
| } |
| |
| ~auto_addrinfo() |
| { |
| if (ai_) |
| socket_ops::freeaddrinfo(ai_); |
| } |
| |
| operator asio::detail::addrinfo_type*() |
| { |
| return ai_; |
| } |
| |
| private: |
| asio::detail::addrinfo_type* ai_; |
| }; |
| #endif // !defined(ASIO_WINDOWS_RUNTIME) |
| |
| // Helper class to run the work scheduler in a thread. |
| class work_scheduler_runner; |
| |
| // Start the work scheduler if it's not already running. |
| ASIO_DECL void start_work_thread(); |
| |
| // The scheduler implementation used to post completions. |
| #if defined(ASIO_HAS_IOCP) |
| typedef class win_iocp_io_context scheduler_impl; |
| #else |
| typedef class scheduler scheduler_impl; |
| #endif |
| scheduler_impl& scheduler_; |
| |
| private: |
| // Mutex to protect access to internal data. |
| asio::detail::mutex mutex_; |
| |
| // Private scheduler used for performing asynchronous host resolution. |
| asio::detail::scoped_ptr<scheduler_impl> work_scheduler_; |
| |
| // Thread used for running the work io_context's run loop. |
| asio::detail::scoped_ptr<asio::detail::thread> work_thread_; |
| }; |
| |
| } // namespace detail |
| } // namespace asio |
| |
| #include "asio/detail/pop_options.hpp" |
| |
| #if defined(ASIO_HEADER_ONLY) |
| # include "asio/detail/impl/resolver_service_base.ipp" |
| #endif // defined(ASIO_HEADER_ONLY) |
| |
| #endif // ASIO_DETAIL_RESOLVER_SERVICE_BASE_HPP |