From e95946831f8ef53d29590735a2df661385edb008 Mon Sep 17 00:00:00 2001 From: "Matthias P. Braendli" Date: Mon, 6 Aug 2018 10:35:22 +0200 Subject: Replace boost by the standalone asio library --- lib/asio/detail/impl/strand_service.hpp | 118 ++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 lib/asio/detail/impl/strand_service.hpp (limited to 'lib/asio/detail/impl/strand_service.hpp') diff --git a/lib/asio/detail/impl/strand_service.hpp b/lib/asio/detail/impl/strand_service.hpp new file mode 100644 index 0000000..da5b716 --- /dev/null +++ b/lib/asio/detail/impl/strand_service.hpp @@ -0,0 +1,118 @@ +// +// detail/impl/strand_service.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_DETAIL_IMPL_STRAND_SERVICE_HPP +#define ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP + +#if defined(_MSC_VER) && (_MSC_VER >= 1200) +# pragma once +#endif // defined(_MSC_VER) && (_MSC_VER >= 1200) + +#include "asio/detail/call_stack.hpp" +#include "asio/detail/completion_handler.hpp" +#include "asio/detail/fenced_block.hpp" +#include "asio/detail/handler_alloc_helpers.hpp" +#include "asio/detail/handler_invoke_helpers.hpp" +#include "asio/detail/memory.hpp" + +#include "asio/detail/push_options.hpp" + +namespace asio { +namespace detail { + +inline strand_service::strand_impl::strand_impl() + : operation(&strand_service::do_complete), + locked_(false) +{ +} + +struct strand_service::on_dispatch_exit +{ + io_context_impl* io_context_; + strand_impl* impl_; + + ~on_dispatch_exit() + { + impl_->mutex_.lock(); + impl_->ready_queue_.push(impl_->waiting_queue_); + bool more_handlers = impl_->locked_ = !impl_->ready_queue_.empty(); + impl_->mutex_.unlock(); + + if (more_handlers) + io_context_->post_immediate_completion(impl_, false); + } +}; + +template +void strand_service::dispatch(strand_service::implementation_type& impl, + Handler& handler) +{ + // If we are already in the strand then the handler can run immediately. + if (call_stack::contains(impl)) + { + fenced_block b(fenced_block::full); + asio_handler_invoke_helpers::invoke(handler, handler); + return; + } + + // Allocate and construct an operation to wrap the handler. + typedef completion_handler op; + typename op::ptr p = { asio::detail::addressof(handler), + op::ptr::allocate(handler), 0 }; + p.p = new (p.v) op(handler); + + ASIO_HANDLER_CREATION((this->context(), + *p.p, "strand", impl, 0, "dispatch")); + + bool dispatch_immediately = do_dispatch(impl, p.p); + operation* o = p.p; + p.v = p.p = 0; + + if (dispatch_immediately) + { + // Indicate that this strand is executing on the current thread. + call_stack::context ctx(impl); + + // Ensure the next handler, if any, is scheduled on block exit. + on_dispatch_exit on_exit = { &io_context_, impl }; + (void)on_exit; + + completion_handler::do_complete( + &io_context_, o, asio::error_code(), 0); + } +} + +// Request the io_context to invoke the given handler and return immediately. +template +void strand_service::post(strand_service::implementation_type& impl, + Handler& handler) +{ + bool is_continuation = + asio_handler_cont_helpers::is_continuation(handler); + + // Allocate and construct an operation to wrap the handler. + typedef completion_handler op; + typename op::ptr p = { asio::detail::addressof(handler), + op::ptr::allocate(handler), 0 }; + p.p = new (p.v) op(handler); + + ASIO_HANDLER_CREATION((this->context(), + *p.p, "strand", impl, 0, "post")); + + do_post(impl, p.p, is_continuation); + p.v = p.p = 0; +} + +} // namespace detail +} // namespace asio + +#include "asio/detail/pop_options.hpp" + +#endif // ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP -- cgit v1.2.3