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

   1 //
   2 // detail/descriptor_write_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_DESCRIPTOR_WRITE_OP_HPP
  12 #define BOOST_ASIO_DETAIL_DESCRIPTOR_WRITE_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
  20 #if !defined(BOOST_ASIO_WINDOWS) && !defined(__CYGWIN__)
  21
  22 #include <boost/asio/detail/bind_handler.hpp>
  23 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
  24 #include <boost/asio/detail/descriptor_ops.hpp>
  25 #include <boost/asio/detail/fenced_block.hpp>
  26 #include <boost/asio/detail/handler_work.hpp>
  27 #include <boost/asio/detail/memory.hpp>
  28 #include <boost/asio/detail/reactor_op.hpp>
  29
  30 #include <boost/asio/detail/push_options.hpp>
  31
  32 namespace boost {
  33 namespace asio {
  34 namespace detail {
  35
  36 template <typename ConstBufferSequence>
  37 class descriptor_write_op_base : public reactor_op
  38 {
  39 public:
  40   descriptor_write_op_base(const boost::system::error_code& success_ec,
  41       int descriptor, const ConstBufferSequence& buffers,
  42       func_type complete_func)
  43     : reactor_op(success_ec,
  44         &descriptor_write_op_base::do_perform, complete_func),
  45       descriptor_(descriptor),
  46       buffers_(buffers)
  47   {
  48   }
  49
  50   static status do_perform(reactor_op* base)
  51   {
  52     descriptor_write_op_base* o(static_cast<descriptor_write_op_base*>(base));
  53
  54     typedef buffer_sequence_adapter<boost::asio::const_buffer,
  55         ConstBufferSequence> bufs_type;
  56
  57     status result;
  58     if (bufs_type::is_single_buffer)
  59     {
  60       result = descriptor_ops::non_blocking_write1(o->descriptor_,
  61           bufs_type::first(o->buffers_).data(),
  62           bufs_type::first(o->buffers_).size(),
  63           o->ec_, o->bytes_transferred_) ? done : not_done;
  64     }
  65     else
  66     {
  67       bufs_type bufs(o->buffers_);
  68       result = descriptor_ops::non_blocking_write(o->descriptor_,
  69           bufs.buffers(), bufs.count(), o->ec_, o->bytes_transferred_)
  70         ? done : not_done;
  71     }
  72
  73     BOOST_ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_write",
  74           o->ec_, o->bytes_transferred_));
  75
  76     return result;
  77   }
  78
  79 private:
  80   int descriptor_;
  81   ConstBufferSequence buffers_;
  82 };
  83
  84 template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
  85 class descriptor_write_op
  86   : public descriptor_write_op_base<ConstBufferSequence>
  87 {
  88 public:
  89   BOOST_ASIO_DEFINE_HANDLER_PTR(descriptor_write_op);
  90
  91   descriptor_write_op(const boost::system::error_code& success_ec,
  92       int descriptor, const ConstBufferSequence& buffers,
  93       Handler& handler, const IoExecutor& io_ex)
  94     : descriptor_write_op_base<ConstBufferSequence>(success_ec,
  95         descriptor, buffers, &descriptor_write_op::do_complete),
  96       handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
  97       work_(handler_, io_ex)
  98   {
  99   }
 100
 101   static void do_complete(void* owner, operation* base,
 102       const boost::system::error_code& /*ec*/,
 103       std::size_t /*bytes_transferred*/)
 104   {
 105     // Take ownership of the handler object.
 106     descriptor_write_op* o(static_cast<descriptor_write_op*>(base));
 107     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
 108
 109     BOOST_ASIO_HANDLER_COMPLETION((*o));
 110
 111     // Take ownership of the operation's outstanding work.
 112     handler_work<Handler, IoExecutor> w(
 113         BOOST_ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
 114           o->work_));
 115
 116     // Make a copy of the handler so that the memory can be deallocated before
 117     // the upcall is made. Even if we're not about to make an upcall, a
 118     // sub-object of the handler may be the true owner of the memory associated
 119     // with the handler. Consequently, a local copy of the handler is required
 120     // to ensure that any owning sub-object remains valid until after we have
 121     // deallocated the memory here.
 122     detail::binder2<Handler, boost::system::error_code, std::size_t>
 123       handler(o->handler_, o->ec_, o->bytes_transferred_);
 124     p.h = boost::asio::detail::addressof(handler.handler_);
 125     p.reset();
 126
 127     // Make the upcall if required.
 128     if (owner)
 129     {
 130       fenced_block b(fenced_block::half);
 131       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
 132       w.complete(handler, handler.handler_);
 133       BOOST_ASIO_HANDLER_INVOCATION_END;
 134     }
 135   }
 136
 137 private:
 138   Handler handler_;
 139   handler_work<Handler, IoExecutor> work_;
 140 };
 141
 142 } // namespace detail
 143 } // namespace asio
 144 } // namespace boost
 145
 146 #include <boost/asio/detail/pop_options.hpp>
 147
 148 #endif // !defined(BOOST_ASIO_WINDOWS) && !defined(__CYGWIN__)
 149
 150 #endif // BOOST_ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP