ceph/src/boost/boost/asio/any_io_executor.hpp

   1 //
   2 // any_io_executor.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_ANY_IO_EXECUTOR_HPP
  12 #define BOOST_ASIO_ANY_IO_EXECUTOR_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 #if defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
  20 # include <boost/asio/executor.hpp>
  21 #else // defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
  22 # include <boost/asio/execution.hpp>
  23 # include <boost/asio/execution_context.hpp>
  24 #endif // defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
  25
  26 #include <boost/asio/detail/push_options.hpp>
  27
  28 namespace boost {
  29 namespace asio {
  30
  31 #if defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
  32
  33 typedef executor any_io_executor;
  34
  35 #else // defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
  36
  37 /// Polymorphic executor type for use with I/O objects.
  38 /**
  39  * The @c any_io_executor type is a polymorphic executor that supports the set
  40  * of properties required by I/O objects. It is defined as the
  41  * execution::any_executor class template parameterised as follows:
  42  * @code execution::any_executor<
  43  *   execution::context_as_t<execution_context&>,
  44  *   execution::blocking_t::never_t,
  45  *   execution::prefer_only<execution::blocking_t::possibly_t>,
  46  *   execution::prefer_only<execution::outstanding_work_t::tracked_t>,
  47  *   execution::prefer_only<execution::outstanding_work_t::untracked_t>,
  48  *   execution::prefer_only<execution::relationship_t::fork_t>,
  49  *   execution::prefer_only<execution::relationship_t::continuation_t>
  50  * > @endcode
  51  */
  52 class any_io_executor :
  53 #if defined(GENERATING_DOCUMENTATION)
  54   public execution::any_executor<...>
  55 #else // defined(GENERATING_DOCUMENTATION)
  56   public execution::any_executor<
  57       execution::context_as_t<execution_context&>,
  58       execution::blocking_t::never_t,
  59       execution::prefer_only<execution::blocking_t::possibly_t>,
  60       execution::prefer_only<execution::outstanding_work_t::tracked_t>,
  61       execution::prefer_only<execution::outstanding_work_t::untracked_t>,
  62       execution::prefer_only<execution::relationship_t::fork_t>,
  63       execution::prefer_only<execution::relationship_t::continuation_t>
  64     >
  65 #endif // defined(GENERATING_DOCUMENTATION)
  66 {
  67 public:
  68 #if !defined(GENERATING_DOCUMENTATION)
  69   typedef execution::any_executor<
  70       execution::context_as_t<execution_context&>,
  71       execution::blocking_t::never_t,
  72       execution::prefer_only<execution::blocking_t::possibly_t>,
  73       execution::prefer_only<execution::outstanding_work_t::tracked_t>,
  74       execution::prefer_only<execution::outstanding_work_t::untracked_t>,
  75       execution::prefer_only<execution::relationship_t::fork_t>,
  76       execution::prefer_only<execution::relationship_t::continuation_t>
  77     > base_type;
  78
  79   typedef void supportable_properties_type(
  80       execution::context_as_t<execution_context&>,
  81       execution::blocking_t::never_t,
  82       execution::prefer_only<execution::blocking_t::possibly_t>,
  83       execution::prefer_only<execution::outstanding_work_t::tracked_t>,
  84       execution::prefer_only<execution::outstanding_work_t::untracked_t>,
  85       execution::prefer_only<execution::relationship_t::fork_t>,
  86       execution::prefer_only<execution::relationship_t::continuation_t>
  87     );
  88 #endif // !defined(GENERATING_DOCUMENTATION)
  89
  90   /// Default constructor.
  91   BOOST_ASIO_DECL any_io_executor() BOOST_ASIO_NOEXCEPT;
  92
  93   /// Construct in an empty state. Equivalent effects to default constructor.
  94   BOOST_ASIO_DECL any_io_executor(nullptr_t) BOOST_ASIO_NOEXCEPT;
  95
  96   /// Copy constructor.
  97   BOOST_ASIO_DECL any_io_executor(const any_io_executor& e) BOOST_ASIO_NOEXCEPT;
  98
  99 #if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
 100   /// Move constructor.
 101   BOOST_ASIO_DECL any_io_executor(any_io_executor&& e) BOOST_ASIO_NOEXCEPT;
 102 #endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
 103
 104   /// Construct to point to the same target as another any_executor.
 105 #if defined(GENERATING_DOCUMENTATION)
 106   template <class... OtherSupportableProperties>
 107     any_io_executor(execution::any_executor<OtherSupportableProperties...> e);
 108 #else // defined(GENERATING_DOCUMENTATION)
 109   template <typename OtherAnyExecutor>
 110   any_io_executor(OtherAnyExecutor e,
 111       typename constraint<
 112         conditional<
 113           !is_same<OtherAnyExecutor, any_io_executor>::value
 114             && is_base_of<execution::detail::any_executor_base,
 115               OtherAnyExecutor>::value,
 116           typename execution::detail::supportable_properties<
 117             0, supportable_properties_type>::template
 118               is_valid_target<OtherAnyExecutor>,
 119           false_type
 120         >::type::value
 121       >::type = 0)
 122     : base_type(BOOST_ASIO_MOVE_CAST(OtherAnyExecutor)(e))
 123   {
 124   }
 125 #endif // defined(GENERATING_DOCUMENTATION)
 126
 127   /// Construct a polymorphic wrapper for the specified executor.
 128 #if defined(GENERATING_DOCUMENTATION)
 129   template <BOOST_ASIO_EXECUTION_EXECUTOR Executor>
 130   any_io_executor(Executor e);
 131 #else // defined(GENERATING_DOCUMENTATION)
 132   template <BOOST_ASIO_EXECUTION_EXECUTOR Executor>
 133   any_io_executor(Executor e,
 134       typename constraint<
 135         conditional<
 136           !is_same<Executor, any_io_executor>::value
 137             && !is_base_of<execution::detail::any_executor_base,
 138               Executor>::value,
 139           execution::detail::is_valid_target_executor<
 140             Executor, supportable_properties_type>,
 141           false_type
 142         >::type::value
 143       >::type = 0)
 144     : base_type(BOOST_ASIO_MOVE_CAST(Executor)(e))
 145   {
 146   }
 147 #endif // defined(GENERATING_DOCUMENTATION)
 148
 149   /// Assignment operator.
 150   BOOST_ASIO_DECL any_io_executor& operator=(
 151       const any_io_executor& e) BOOST_ASIO_NOEXCEPT;
 152
 153 #if defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
 154   /// Move assignment operator.
 155   BOOST_ASIO_DECL any_io_executor& operator=(
 156       any_io_executor&& e) BOOST_ASIO_NOEXCEPT;
 157 #endif // defined(BOOST_ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
 158
 159   /// Assignment operator that sets the polymorphic wrapper to the empty state.
 160   BOOST_ASIO_DECL any_io_executor& operator=(nullptr_t);
 161
 162   /// Destructor.
 163   BOOST_ASIO_DECL ~any_io_executor();
 164
 165   /// Swap targets with another polymorphic wrapper.
 166   BOOST_ASIO_DECL void swap(any_io_executor& other) BOOST_ASIO_NOEXCEPT;
 167
 168   /// Obtain a polymorphic wrapper with the specified property.
 169   /**
 170    * Do not call this function directly. It is intended for use with the
 171    * boost::asio::require and boost::asio::prefer customisation points.
 172    *
 173    * For example:
 174    * @code any_io_executor ex = ...;
 175    * auto ex2 = boost::asio::require(ex, execution::blocking.possibly); @endcode
 176    */
 177   template <typename Property>
 178   any_io_executor require(const Property& p,
 179       typename constraint<
 180         traits::require_member<const base_type&, const Property&>::is_valid
 181       >::type = 0) const
 182   {
 183     return static_cast<const base_type&>(*this).require(p);
 184   }
 185
 186   /// Obtain a polymorphic wrapper with the specified property.
 187   /**
 188    * Do not call this function directly. It is intended for use with the
 189    * boost::asio::prefer customisation point.
 190    *
 191    * For example:
 192    * @code any_io_executor ex = ...;
 193    * auto ex2 = boost::asio::prefer(ex, execution::blocking.possibly); @endcode
 194    */
 195   template <typename Property>
 196   any_io_executor prefer(const Property& p,
 197       typename constraint<
 198         traits::prefer_member<const base_type&, const Property&>::is_valid
 199       >::type = 0) const
 200   {
 201     return static_cast<const base_type&>(*this).prefer(p);
 202   }
 203 };
 204
 205 #if !defined(GENERATING_DOCUMENTATION)
 206
 207 template <>
 208 BOOST_ASIO_DECL any_io_executor any_io_executor::require(
 209     const execution::blocking_t::never_t&, int) const;
 210
 211 template <>
 212 BOOST_ASIO_DECL any_io_executor any_io_executor::prefer(
 213     const execution::blocking_t::possibly_t&, int) const;
 214
 215 template <>
 216 BOOST_ASIO_DECL any_io_executor any_io_executor::prefer(
 217     const execution::outstanding_work_t::tracked_t&, int) const;
 218
 219 template <>
 220 BOOST_ASIO_DECL any_io_executor any_io_executor::prefer(
 221     const execution::outstanding_work_t::untracked_t&, int) const;
 222
 223 template <>
 224 BOOST_ASIO_DECL any_io_executor any_io_executor::prefer(
 225     const execution::relationship_t::fork_t&, int) const;
 226
 227 template <>
 228 BOOST_ASIO_DECL any_io_executor any_io_executor::prefer(
 229     const execution::relationship_t::continuation_t&, int) const;
 230
 231 namespace traits {
 232
 233 #if !defined(BOOST_ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
 234
 235 template <>
 236 struct equality_comparable<any_io_executor>
 237 {
 238   static const bool is_valid = true;
 239   static const bool is_noexcept = true;
 240 };
 241
 242 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
 243
 244 #if !defined(BOOST_ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
 245
 246 template <typename F>
 247 struct execute_member<any_io_executor, F>
 248 {
 249   static const bool is_valid = true;
 250   static const bool is_noexcept = false;
 251   typedef void result_type;
 252 };
 253
 254 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
 255
 256 #if !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
 257
 258 template <typename Prop>
 259 struct query_member<any_io_executor, Prop> :
 260   query_member<any_io_executor::base_type, Prop>
 261 {
 262 };
 263
 264 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
 265
 266 #if !defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
 267
 268 template <typename Prop>
 269 struct require_member<any_io_executor, Prop> :
 270   require_member<any_io_executor::base_type, Prop>
 271 {
 272   typedef any_io_executor result_type;
 273 };
 274
 275 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
 276
 277 #if !defined(BOOST_ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
 278
 279 template <typename Prop>
 280 struct prefer_member<any_io_executor, Prop> :
 281   prefer_member<any_io_executor::base_type, Prop>
 282 {
 283   typedef any_io_executor result_type;
 284 };
 285
 286 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
 287
 288 } // namespace traits
 289
 290 #endif // !defined(GENERATING_DOCUMENTATION)
 291
 292 #endif // defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
 293
 294 } // namespace asio
 295 } // namespace boost
 296
 297 #include <boost/asio/detail/pop_options.hpp>
 298
 299 #if defined(BOOST_ASIO_HEADER_ONLY) \
 300   && !defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
 301 # include <boost/asio/impl/any_io_executor.ipp>
 302 #endif // defined(BOOST_ASIO_HEADER_ONLY)
 303        //   && !defined(BOOST_ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
 304
 305 #endif // BOOST_ASIO_ANY_IO_EXECUTOR_HPP