| // |
| // detail/resolve_op.hpp |
| // ~~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2010 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_RESOLVE_OP_HPP |
| #define BOOST_ASIO_DETAIL_RESOLVE_OP_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/utility/addressof.hpp> |
| #include <boost/asio/error.hpp> |
| #include <boost/asio/io_service.hpp> |
| #include <boost/asio/ip/basic_resolver_iterator.hpp> |
| #include <boost/asio/ip/basic_resolver_query.hpp> |
| #include <boost/asio/detail/bind_handler.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/socket_ops.hpp> |
| |
| #include <boost/asio/detail/push_options.hpp> |
| |
| namespace boost { |
| namespace asio { |
| namespace detail { |
| |
| template <typename Protocol, typename Handler> |
| class resolve_op : public operation |
| { |
| public: |
| BOOST_ASIO_DEFINE_HANDLER_PTR(resolve_op); |
| |
| typedef boost::asio::ip::basic_resolver_query<Protocol> query_type; |
| typedef boost::asio::ip::basic_resolver_iterator<Protocol> iterator_type; |
| |
| resolve_op(socket_ops::weak_cancel_token_type cancel_token, |
| const query_type& query, io_service_impl& ios, Handler handler) |
| : operation(&resolve_op::do_complete), |
| cancel_token_(cancel_token), |
| query_(query), |
| io_service_impl_(ios), |
| handler_(handler), |
| addrinfo_(0) |
| { |
| } |
| |
| ~resolve_op() |
| { |
| if (addrinfo_) |
| socket_ops::freeaddrinfo(addrinfo_); |
| } |
| |
| static void do_complete(io_service_impl* owner, operation* base, |
| boost::system::error_code /*ec*/, std::size_t /*bytes_transferred*/) |
| { |
| // Take ownership of the operation object. |
| resolve_op* o(static_cast<resolve_op*>(base)); |
| ptr p = { boost::addressof(o->handler_), o, o }; |
| |
| if (owner && owner != &o->io_service_impl_) |
| { |
| // The operation is being run on the worker io_service. Time to perform |
| // the resolver operation. |
| |
| // Perform the blocking host resolution operation. |
| socket_ops::background_getaddrinfo(o->cancel_token_, |
| o->query_.host_name().c_str(), o->query_.service_name().c_str(), |
| o->query_.hints(), &o->addrinfo_, o->ec_); |
| |
| // Pass operation back to main io_service for completion. |
| o->io_service_impl_.post_deferred_completion(o); |
| p.v = p.p = 0; |
| } |
| else |
| { |
| // The operation has been returned to the main io_service. The completion |
| // handler is ready to be delivered. |
| |
| // 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. |
| detail::binder2<Handler, boost::system::error_code, iterator_type> |
| handler(o->handler_, o->ec_, iterator_type()); |
| p.h = boost::addressof(handler.handler_); |
| if (o->addrinfo_) |
| { |
| handler.arg2_ = iterator_type::create(o->addrinfo_, |
| o->query_.host_name(), o->query_.service_name()); |
| } |
| p.reset(); |
| |
| if (owner) |
| { |
| boost::asio::detail::fenced_block b; |
| boost_asio_handler_invoke_helpers::invoke(handler, handler.handler_); |
| } |
| } |
| } |
| |
| private: |
| socket_ops::weak_cancel_token_type cancel_token_; |
| query_type query_; |
| io_service_impl& io_service_impl_; |
| Handler handler_; |
| boost::system::error_code ec_; |
| boost::asio::detail::addrinfo_type* addrinfo_; |
| }; |
| |
| } // namespace detail |
| } // namespace asio |
| } // namespace boost |
| |
| #include <boost/asio/detail/pop_options.hpp> |
| |
| #endif // BOOST_ASIO_DETAIL_RESOLVE_OP_HPP |