ceph/src/boost/boost/asio/experimental/detail/channel_operation.hpp

   1 //
   2 // experimental/detail/channel_operation.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_EXPERIMENTAL_DETAIL_CHANNEL_OPERATION_HPP
  12 #define BOOST_ASIO_EXPERIMENTAL_DETAIL_CHANNEL_OPERATION_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/associated_allocator.hpp>
  20 #include <boost/asio/associated_executor.hpp>
  21 #include <boost/asio/detail/op_queue.hpp>
  22 #include <boost/asio/execution/executor.hpp>
  23 #include <boost/asio/execution/outstanding_work.hpp>
  24 #include <boost/asio/executor_work_guard.hpp>
  25 #include <boost/asio/prefer.hpp>
  26
  27 #include <boost/asio/detail/push_options.hpp>
  28
  29 namespace boost {
  30 namespace asio {
  31 namespace experimental {
  32 namespace detail {
  33
  34 // Base class for all channel operations. A function pointer is used instead of
  35 // virtual functions to avoid the associated overhead.
  36 class channel_operation BOOST_ASIO_INHERIT_TRACKED_HANDLER
  37 {
  38 public:
  39   template <typename Executor, typename = void>
  40   class handler_work_base;
  41
  42   template <typename Handler, typename IoExecutor, typename = void>
  43   class handler_work;
  44
  45   void destroy()
  46   {
  47     func_(this, destroy_op, 0);
  48   }
  49
  50 protected:
  51   enum action
  52   {
  53     destroy_op = 0,
  54     complete_op = 1,
  55     cancel_op = 2,
  56     close_op = 3
  57   };
  58
  59   typedef void (*func_type)(channel_operation*, action, void*);
  60
  61   channel_operation(func_type func)
  62     : next_(0),
  63       func_(func),
  64       cancellation_key_(0)
  65   {
  66   }
  67
  68   // Prevents deletion through this type.
  69   ~channel_operation()
  70   {
  71   }
  72
  73   friend class boost::asio::detail::op_queue_access;
  74   channel_operation* next_;
  75   func_type func_;
  76
  77 public:
  78   // The operation key used for targeted cancellation.
  79   void* cancellation_key_;
  80 };
  81
  82 template <typename Executor, typename>
  83 class channel_operation::handler_work_base
  84 {
  85 public:
  86   handler_work_base(int, const Executor& ex)
  87     : executor_(boost::asio::prefer(ex, execution::outstanding_work.tracked))
  88   {
  89   }
  90
  91   template <typename Function, typename Handler>
  92   void post(Function& function, Handler& handler)
  93   {
  94     typename associated_allocator<Handler>::type allocator =
  95       (get_associated_allocator)(handler);
  96
  97     execution::execute(
  98         boost::asio::prefer(
  99           boost::asio::require(executor_, execution::blocking.never),
 100           execution::allocator(allocator)),
 101         BOOST_ASIO_MOVE_CAST(Function)(function));
 102   }
 103
 104 private:
 105   typename decay<
 106       typename prefer_result<Executor,
 107         execution::outstanding_work_t::tracked_t
 108       >::type
 109     >::type executor_;
 110 };
 111
 112 #if !defined(BOOST_ASIO_NO_TS_EXECUTORS)
 113
 114 template <typename Executor>
 115 class channel_operation::handler_work_base<Executor,
 116     typename enable_if<
 117       !execution::is_executor<Executor>::value
 118     >::type>
 119 {
 120 public:
 121   handler_work_base(int, const Executor& ex)
 122     : work_(ex)
 123   {
 124   }
 125
 126   template <typename Function, typename Handler>
 127   void post(Function& function, Handler& handler)
 128   {
 129     typename associated_allocator<Handler>::type allocator =
 130       (get_associated_allocator)(handler);
 131
 132     work_.get_executor().post(
 133         BOOST_ASIO_MOVE_CAST(Function)(function), allocator);
 134   }
 135
 136 private:
 137   executor_work_guard<Executor> work_;
 138 };
 139
 140 #endif // !defined(BOOST_ASIO_NO_TS_EXECUTORS)
 141
 142 template <typename Handler, typename IoExecutor, typename>
 143 class channel_operation::handler_work :
 144   channel_operation::handler_work_base<IoExecutor>,
 145   channel_operation::handler_work_base<
 146       typename associated_executor<Handler, IoExecutor>::type, IoExecutor>
 147 {
 148 public:
 149   typedef channel_operation::handler_work_base<IoExecutor> base1_type;
 150
 151   typedef channel_operation::handler_work_base<
 152       typename associated_executor<Handler, IoExecutor>::type, IoExecutor>
 153     base2_type;
 154
 155   handler_work(Handler& handler, const IoExecutor& io_ex) BOOST_ASIO_NOEXCEPT
 156     : base1_type(0, io_ex),
 157       base2_type(0, (get_associated_executor)(handler, io_ex))
 158   {
 159   }
 160
 161   template <typename Function>
 162   void complete(Function& function, Handler& handler)
 163   {
 164     base2_type::post(function, handler);
 165   }
 166 };
 167
 168 template <typename Handler, typename IoExecutor>
 169 class channel_operation::handler_work<
 170     Handler, IoExecutor,
 171     typename enable_if<
 172       is_same<
 173         typename associated_executor<Handler,
 174           IoExecutor>::asio_associated_executor_is_unspecialised,
 175         void
 176       >::value
 177     >::type> : handler_work_base<IoExecutor>
 178 {
 179 public:
 180   typedef channel_operation::handler_work_base<IoExecutor> base1_type;
 181
 182   handler_work(Handler&, const IoExecutor& io_ex) BOOST_ASIO_NOEXCEPT
 183     : base1_type(0, io_ex)
 184   {
 185   }
 186
 187   template <typename Function>
 188   void complete(Function& function, Handler& handler)
 189   {
 190     base1_type::post(function, handler);
 191   }
 192 };
 193
 194 } // namespace detail
 195 } // namespace experimental
 196 } // namespace asio
 197 } // namespace boost
 198
 199 #include <boost/asio/detail/pop_options.hpp>
 200
 201 #endif // BOOST_ASIO_EXPERIMENTAL_DETAIL_CHANNEL_OPERATION_HPP