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

   1 //
   2 // detail/io_uring_socket_recvmsg_op.hpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2022 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_IO_URING_SOCKET_RECVMSG_OP_HPP
  12 #define BOOST_ASIO_DETAIL_IO_URING_SOCKET_RECVMSG_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_HAS_IO_URING)
  21
  22 #include <boost/asio/detail/bind_handler.hpp>
  23 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
  24 #include <boost/asio/detail/socket_ops.hpp>
  25 #include <boost/asio/detail/fenced_block.hpp>
  26 #include <boost/asio/detail/handler_work.hpp>
  27 #include <boost/asio/detail/io_uring_operation.hpp>
  28 #include <boost/asio/detail/memory.hpp>
  29
  30 #include <boost/asio/detail/push_options.hpp>
  31
  32 namespace boost {
  33 namespace asio {
  34 namespace detail {
  35
  36 template <typename MutableBufferSequence>
  37 class io_uring_socket_recvmsg_op_base : public io_uring_operation
  38 {
  39 public:
  40   io_uring_socket_recvmsg_op_base(const boost::system::error_code& success_ec,
  41       socket_type socket, socket_ops::state_type state,
  42       const MutableBufferSequence& buffers, socket_base::message_flags in_flags,
  43       socket_base::message_flags& out_flags, func_type complete_func)
  44     : io_uring_operation(success_ec,
  45         &io_uring_socket_recvmsg_op_base::do_prepare,
  46         &io_uring_socket_recvmsg_op_base::do_perform, complete_func),
  47       socket_(socket),
  48       state_(state),
  49       buffers_(buffers),
  50       in_flags_(in_flags),
  51       out_flags_(out_flags),
  52       bufs_(buffers),
  53       msghdr_()
  54   {
  55     msghdr_.msg_iov = bufs_.buffers();
  56     msghdr_.msg_iovlen = static_cast<int>(bufs_.count());
  57   }
  58
  59   static void do_prepare(io_uring_operation* base, ::io_uring_sqe* sqe)
  60   {
  61     io_uring_socket_recvmsg_op_base* o(
  62         static_cast<io_uring_socket_recvmsg_op_base*>(base));
  63
  64     if ((o->state_ & socket_ops::internal_non_blocking) != 0)
  65     {
  66       bool except_op = (o->in_flags_ & socket_base::message_out_of_band) != 0;
  67       ::io_uring_prep_poll_add(sqe, o->socket_, except_op ? POLLPRI : POLLIN);
  68     }
  69     else
  70     {
  71       ::io_uring_prep_recvmsg(sqe, o->socket_, &o->msghdr_, o->in_flags_);
  72     }
  73   }
  74
  75   static bool do_perform(io_uring_operation* base, bool after_completion)
  76   {
  77     io_uring_socket_recvmsg_op_base* o(
  78         static_cast<io_uring_socket_recvmsg_op_base*>(base));
  79
  80     if ((o->state_ & socket_ops::internal_non_blocking) != 0)
  81     {
  82       bool except_op = (o->in_flags_ & socket_base::message_out_of_band) != 0;
  83       if (after_completion || !except_op)
  84       {
  85         return socket_ops::non_blocking_recvmsg(o->socket_,
  86             o->bufs_.buffers(), o->bufs_.count(), o->in_flags_,
  87             o->out_flags_, o->ec_, o->bytes_transferred_);
  88       }
  89     }
  90     else if (after_completion)
  91     {
  92       if (!o->ec_)
  93         o->out_flags_ = o->msghdr_.msg_flags;
  94       else
  95         o->out_flags_ = 0;
  96     }
  97
  98     if (o->ec_ && o->ec_ == boost::asio::error::would_block)
  99     {
 100       o->state_ |= socket_ops::internal_non_blocking;
 101       return false;
 102     }
 103
 104     return after_completion;
 105   }
 106
 107 private:
 108   socket_type socket_;
 109   socket_ops::state_type state_;
 110   MutableBufferSequence buffers_;
 111   socket_base::message_flags in_flags_;
 112   socket_base::message_flags& out_flags_;
 113   buffer_sequence_adapter<boost::asio::mutable_buffer,
 114       MutableBufferSequence> bufs_;
 115   msghdr msghdr_;
 116 };
 117
 118 template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
 119 class io_uring_socket_recvmsg_op
 120   : public io_uring_socket_recvmsg_op_base<MutableBufferSequence>
 121 {
 122 public:
 123   BOOST_ASIO_DEFINE_HANDLER_PTR(io_uring_socket_recvmsg_op);
 124
 125   io_uring_socket_recvmsg_op(const boost::system::error_code& success_ec,
 126       int socket, socket_ops::state_type state,
 127       const MutableBufferSequence& buffers,
 128       socket_base::message_flags in_flags,
 129       socket_base::message_flags& out_flags,
 130       Handler& handler, const IoExecutor& io_ex)
 131     : io_uring_socket_recvmsg_op_base<MutableBufferSequence>(success_ec,
 132         socket, state, buffers, in_flags, out_flags,
 133         &io_uring_socket_recvmsg_op::do_complete),
 134       handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)),
 135       work_(handler_, io_ex)
 136   {
 137   }
 138
 139   static void do_complete(void* owner, operation* base,
 140       const boost::system::error_code& /*ec*/,
 141       std::size_t /*bytes_transferred*/)
 142   {
 143     // Take ownership of the handler object.
 144     io_uring_socket_recvmsg_op* o
 145       (static_cast<io_uring_socket_recvmsg_op*>(base));
 146     ptr p = { boost::asio::detail::addressof(o->handler_), o, o };
 147
 148     BOOST_ASIO_HANDLER_COMPLETION((*o));
 149
 150     // Take ownership of the operation's outstanding work.
 151     handler_work<Handler, IoExecutor> w(
 152         BOOST_ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
 153           o->work_));
 154
 155     // Make a copy of the handler so that the memory can be deallocated before
 156     // the upcall is made. Even if we're not about to make an upcall, a
 157     // sub-object of the handler may be the true owner of the memory associated
 158     // with the handler. Consequently, a local copy of the handler is required
 159     // to ensure that any owning sub-object remains valid until after we have
 160     // deallocated the memory here.
 161     detail::binder2<Handler, boost::system::error_code, std::size_t>
 162       handler(o->handler_, o->ec_, o->bytes_transferred_);
 163     p.h = boost::asio::detail::addressof(handler.handler_);
 164     p.reset();
 165
 166     // Make the upcall if required.
 167     if (owner)
 168     {
 169       fenced_block b(fenced_block::half);
 170       BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
 171       w.complete(handler, handler.handler_);
 172       BOOST_ASIO_HANDLER_INVOCATION_END;
 173     }
 174   }
 175
 176 private:
 177   Handler handler_;
 178   handler_work<Handler, IoExecutor> work_;
 179 };
 180
 181 } // namespace detail
 182 } // namespace asio
 183 } // namespace boost
 184
 185 #include <boost/asio/detail/pop_options.hpp>
 186
 187 #endif // defined(BOOST_ASIO_HAS_IO_URING)
 188
 189 #endif // BOOST_ASIO_DETAIL_IO_URING_SOCKET_RECVMSG_OP_HPP