ceph/src/boost/boost/asio/detail/reactive_wait_op.hpp

   1 //
   2 // detail/reactive_wait_op.hpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2020 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #ifndef BOOST_ASIO_DETAIL_REACTIVE_WAIT_OP_HPP
  12 #define BOOST_ASIO_DETAIL_REACTIVE_WAIT_OP_HPP
  13
  14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  15 # pragma once
  16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  17
  18 #include <boost/asio/detail/config.hpp>
  19 #include <boost/asio/detail/fenced_block.hpp>
  20 #include <boost/asio/detail/handler_alloc_helpers.hpp>
  21 #include <boost/asio/detail/handler_invoke_helpers.hpp>
  22 #include <boost/asio/detail/memory.hpp>
  23 #include <boost/asio/detail/reactor_op.hpp>
  24
  25 #include <boost/asio/detail/push_options.hpp>
  26
  27 namespace boost {
  28 namespace asio {
  29 namespace detail {
  30
  31 template <typename Handler, typename IoExecutor>
  32 class reactive_wait_op : public reactor_op
  33 {
  34 public:
  35   BOOST_ASIO_DEFINE_HANDLER_PTR(reactive_wait_op);
  36
  37   reactive_wait_op(Handler& handler, const IoExecutor& io_ex)
  38     : reactor_op(&reactive_wait_op::do_perform,
  39         &reactive_wait_op::do_complete),
  40       handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
  41       io_executor_(io_ex)
  42   {
  43     handler_work<Handler, IoExecutor>::start(handler_, io_executor_);
  44   }
  45
  46   static status do_perform(reactor_op*)
  47   {
  48     return done;
  49   }
  50
  51   static void do_complete(void* owner, operation* base,
  52       const boost::system::error_code& /*ec*/,
  53       std::size_t /*bytes_transferred*/)
  54   {
  55     // Take ownership of the handler object.
  56     reactive_wait_op* o(static_cast<reactive_wait_op*>(base));
  57     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
  58     handler_work<Handler, IoExecutor> w(o->handler_, o->io_executor_);
  59
  60     BOOST_ASIO_HANDLER_COMPLETION((*o));
  61
  62     // Make a copy of the handler so that the memory can be deallocated before
  63     // the upcall is made. Even if we're not about to make an upcall, a
  64     // sub-object of the handler may be the true owner of the memory associated
  65     // with the handler. Consequently, a local copy of the handler is required
  66     // to ensure that any owning sub-object remains valid until after we have
  67     // deallocated the memory here.
  68     detail::binder1<Handler, boost::system::error_code>
  69       handler(o->handler_, o->ec_);
  70     p.h = boost::asio::detail::addressof(handler.handler_);
  71     p.reset();
  72
  73     // Make the upcall if required.
  74     if (owner)
  75     {
  76       fenced_block b(fenced_block::half);
  77       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
  78       w.complete(handler, handler.handler_);
  79       BOOST_ASIO_HANDLER_INVOCATION_END;
  80     }
  81   }
  82
  83 private:
  84   Handler handler_;
  85   IoExecutor io_executor_;
  86 };
  87
  88 } // namespace detail
  89 } // namespace asio
  90 } // namespace boost
  91
  92 #include <boost/asio/detail/pop_options.hpp>
  93
  94 #endif // BOOST_ASIO_DETAIL_REACTIVE_WAIT_OP_HPP