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

   1 //
   2 // detail/reactive_socket_recv_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_SOCKET_RECV_OP_HPP
  12 #define BOOST_ASIO_DETAIL_REACTIVE_SOCKET_RECV_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/bind_handler.hpp>
  20 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
  21 #include <boost/asio/detail/fenced_block.hpp>
  22 #include <boost/asio/detail/handler_alloc_helpers.hpp>
  23 #include <boost/asio/detail/handler_invoke_helpers.hpp>
  24 #include <boost/asio/detail/handler_work.hpp>
  25 #include <boost/asio/detail/memory.hpp>
  26 #include <boost/asio/detail/reactor_op.hpp>
  27 #include <boost/asio/detail/socket_ops.hpp>
  28
  29 #include <boost/asio/detail/push_options.hpp>
  30
  31 namespace boost {
  32 namespace asio {
  33 namespace detail {
  34
  35 template <typename MutableBufferSequence>
  36 class reactive_socket_recv_op_base : public reactor_op
  37 {
  38 public:
  39   reactive_socket_recv_op_base(const boost::system::error_code& success_ec,
  40       socket_type socket, socket_ops::state_type state,
  41       const MutableBufferSequence& buffers,
  42       socket_base::message_flags flags, func_type complete_func)
  43     : reactor_op(success_ec,
  44         &reactive_socket_recv_op_base::do_perform, complete_func),
  45       socket_(socket),
  46       state_(state),
  47       buffers_(buffers),
  48       flags_(flags)
  49   {
  50   }
  51
  52   static status do_perform(reactor_op* base)
  53   {
  54     reactive_socket_recv_op_base* o(
  55         static_cast<reactive_socket_recv_op_base*>(base));
  56
  57     typedef buffer_sequence_adapter<boost::asio::mutable_buffer,
  58         MutableBufferSequence> bufs_type;
  59
  60     status result;
  61     if (bufs_type::is_single_buffer)
  62     {
  63       result = socket_ops::non_blocking_recv1(o->socket_,
  64           bufs_type::first(o->buffers_).data(),
  65           bufs_type::first(o->buffers_).size(), o->flags_,
  66           (o->state_ & socket_ops::stream_oriented) != 0,
  67           o->ec_, o->bytes_transferred_) ? done : not_done;
  68     }
  69     else
  70     {
  71       bufs_type bufs(o->buffers_);
  72       result = socket_ops::non_blocking_recv(o->socket_,
  73           bufs.buffers(), bufs.count(), o->flags_,
  74           (o->state_ & socket_ops::stream_oriented) != 0,
  75           o->ec_, o->bytes_transferred_) ? done : not_done;
  76     }
  77
  78     if (result == done)
  79       if ((o->state_ & socket_ops::stream_oriented) != 0)
  80         if (o->bytes_transferred_ == 0)
  81           result = done_and_exhausted;
  82
  83     BOOST_ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_recv",
  84           o->ec_, o->bytes_transferred_));
  85
  86     return result;
  87   }
  88
  89 private:
  90   socket_type socket_;
  91   socket_ops::state_type state_;
  92   MutableBufferSequence buffers_;
  93   socket_base::message_flags flags_;
  94 };
  95
  96 template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
  97 class reactive_socket_recv_op :
  98   public reactive_socket_recv_op_base<MutableBufferSequence>
  99 {
 100 public:
 101   BOOST_ASIO_DEFINE_HANDLER_PTR(reactive_socket_recv_op);
 102
 103   reactive_socket_recv_op(const boost::system::error_code& success_ec,
 104       socket_type socket, socket_ops::state_type state,
 105       const MutableBufferSequence& buffers, socket_base::message_flags flags,
 106       Handler& handler, const IoExecutor& io_ex)
 107     : reactive_socket_recv_op_base<MutableBufferSequence>(success_ec, socket,
 108         state, buffers, flags, &reactive_socket_recv_op::do_complete),
 109       handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
 110       work_(handler_, io_ex)
 111   {
 112   }
 113
 114   static void do_complete(void* owner, operation* base,
 115       const boost::system::error_code& /*ec*/,
 116       std::size_t /*bytes_transferred*/)
 117   {
 118     // Take ownership of the handler object.
 119     reactive_socket_recv_op* o(static_cast<reactive_socket_recv_op*>(base));
 120     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
 121
 122     BOOST_ASIO_HANDLER_COMPLETION((*o));
 123
 124     // Take ownership of the operation's outstanding work.
 125     handler_work<Handler, IoExecutor> w(
 126         BOOST_ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
 127           o->work_));
 128
 129     // Make a copy of the handler so that the memory can be deallocated before
 130     // the upcall is made. Even if we're not about to make an upcall, a
 131     // sub-object of the handler may be the true owner of the memory associated
 132     // with the handler. Consequently, a local copy of the handler is required
 133     // to ensure that any owning sub-object remains valid until after we have
 134     // deallocated the memory here.
 135     detail::binder2<Handler, boost::system::error_code, std::size_t>
 136       handler(o->handler_, o->ec_, o->bytes_transferred_);
 137     p.h = boost::asio::detail::addressof(handler.handler_);
 138     p.reset();
 139
 140     // Make the upcall if required.
 141     if (owner)
 142     {
 143       fenced_block b(fenced_block::half);
 144       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
 145       w.complete(handler, handler.handler_);
 146       BOOST_ASIO_HANDLER_INVOCATION_END;
 147     }
 148   }
 149
 150 private:
 151   Handler handler_;
 152   handler_work<Handler, IoExecutor> work_;
 153 };
 154
 155 } // namespace detail
 156 } // namespace asio
 157 } // namespace boost
 158
 159 #include <boost/asio/detail/pop_options.hpp>
 160
 161 #endif // BOOST_ASIO_DETAIL_REACTIVE_SOCKET_RECV_OP_HPP