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Diffstat (limited to 'boost/asio/detail/completion_handler.hpp')
-rw-r--r-- | boost/asio/detail/completion_handler.hpp | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/boost/asio/detail/completion_handler.hpp b/boost/asio/detail/completion_handler.hpp new file mode 100644 index 0000000000..19b4360c6a --- /dev/null +++ b/boost/asio/detail/completion_handler.hpp @@ -0,0 +1,82 @@ +// +// detail/completion_handler.hpp +// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +// +// Copyright (c) 2003-2012 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_COMPLETION_HANDLER_HPP +#define BOOST_ASIO_DETAIL_COMPLETION_HANDLER_HPP + +#if defined(_MSC_VER) && (_MSC_VER >= 1200) +# pragma once +#endif // defined(_MSC_VER) && (_MSC_VER >= 1200) + +#include <boost/asio/detail/config.hpp> +#include <boost/asio/detail/fenced_block.hpp> +#include <boost/asio/detail/handler_alloc_helpers.hpp> +#include <boost/asio/detail/handler_invoke_helpers.hpp> +#include <boost/asio/detail/operation.hpp> + +#include <boost/asio/detail/push_options.hpp> + +namespace boost { +namespace asio { +namespace detail { + +template <typename Handler> +class completion_handler : public operation +{ +public: + BOOST_ASIO_DEFINE_HANDLER_PTR(completion_handler); + + completion_handler(Handler& h) + : operation(&completion_handler::do_complete), + handler_(BOOST_ASIO_MOVE_CAST(Handler)(h)) + { + } + + static void do_complete(io_service_impl* owner, operation* base, + const boost::system::error_code& /*ec*/, + std::size_t /*bytes_transferred*/) + { + // Take ownership of the handler object. + completion_handler* h(static_cast<completion_handler*>(base)); + ptr p = { boost::addressof(h->handler_), h, h }; + + BOOST_ASIO_HANDLER_COMPLETION((h)); + + // Make a copy of the handler so that the memory can be deallocated before + // the upcall is made. Even if we're not about to make an upcall, a + // sub-object of the handler may be the true owner of the memory associated + // with the handler. Consequently, a local copy of the handler is required + // to ensure that any owning sub-object remains valid until after we have + // deallocated the memory here. + Handler handler(BOOST_ASIO_MOVE_CAST(Handler)(h->handler_)); + p.h = boost::addressof(handler); + p.reset(); + + // Make the upcall if required. + if (owner) + { + fenced_block b(fenced_block::half); + BOOST_ASIO_HANDLER_INVOCATION_BEGIN(()); + boost_asio_handler_invoke_helpers::invoke(handler, handler); + BOOST_ASIO_HANDLER_INVOCATION_END; + } + } + +private: + Handler handler_; +}; + +} // namespace detail +} // namespace asio +} // namespace boost + +#include <boost/asio/detail/pop_options.hpp> + +#endif // BOOST_ASIO_DETAIL_COMPLETION_HANDLER_HPP |