Edit: /usr/include/boost/asio/system_executor.hpp (22529B)
//
// system_executor.hpp
// ~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#ifndef BOOST_ASIO_SYSTEM_EXECUTOR_HPP
#define BOOST_ASIO_SYSTEM_EXECUTOR_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include
#include
#include
#include
namespace boost {
namespace asio {
class system_context;
/// An executor that uses arbitrary threads.
/**
* The system executor represents an execution context where functions are
* permitted to run on arbitrary threads. When the blocking.never property is
* established, the system executor will schedule the function to run on an
* unspecified system thread pool. When either blocking.possibly or
* blocking.always is established, the executor invokes the function
* immediately.
*/
template
class basic_system_executor
{
public:
/// Default constructor.
basic_system_executor() BOOST_ASIO_NOEXCEPT
: allocator_(Allocator())
{
}
/// Obtain an executor with the @c blocking.possibly property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::blocking.possibly); @endcode
*/
basic_system_executor
require(execution::blocking_t::possibly_t) const
{
return basic_system_executor(allocator_);
}
/// Obtain an executor with the @c blocking.always property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::blocking.always); @endcode
*/
basic_system_executor
require(execution::blocking_t::always_t) const
{
return basic_system_executor(allocator_);
}
/// Obtain an executor with the @c blocking.never property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::blocking.never); @endcode
*/
basic_system_executor
require(execution::blocking_t::never_t) const
{
return basic_system_executor(allocator_);
}
/// Obtain an executor with the @c relationship.continuation property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::relationship.continuation); @endcode
*/
basic_system_executor
require(execution::relationship_t::continuation_t) const
{
return basic_system_executor(allocator_);
}
/// Obtain an executor with the @c relationship.fork property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::relationship.fork); @endcode
*/
basic_system_executor
require(execution::relationship_t::fork_t) const
{
return basic_system_executor(allocator_);
}
/// Obtain an executor with the specified @c allocator property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::allocator(my_allocator)); @endcode
*/
template
basic_system_executor
require(execution::allocator_t a) const
{
return basic_system_executor(a.value());
}
/// Obtain an executor with the default @c allocator property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::require customisation point.
*
* For example:
* @code boost::asio::system_executor ex1;
* auto ex2 = boost::asio::require(ex1,
* boost::asio::execution::allocator); @endcode
*/
basic_system_executor >
require(execution::allocator_t) const
{
return basic_system_executor >();
}
/// Query the current value of the @c mapping property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* if (boost::asio::query(ex, boost::asio::execution::mapping)
* == boost::asio::execution::mapping.thread)
* ... @endcode
*/
static BOOST_ASIO_CONSTEXPR execution::mapping_t query(
execution::mapping_t) BOOST_ASIO_NOEXCEPT
{
return execution::mapping.thread;
}
/// Query the current value of the @c context property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* boost::asio::system_context& pool = boost::asio::query(
* ex, boost::asio::execution::context); @endcode
*/
static system_context& query(execution::context_t) BOOST_ASIO_NOEXCEPT;
/// Query the current value of the @c blocking property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* if (boost::asio::query(ex, boost::asio::execution::blocking)
* == boost::asio::execution::blocking.always)
* ... @endcode
*/
static BOOST_ASIO_CONSTEXPR execution::blocking_t query(
execution::blocking_t) BOOST_ASIO_NOEXCEPT
{
return Blocking();
}
/// Query the current value of the @c relationship property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* if (boost::asio::query(ex, boost::asio::execution::relationship)
* == boost::asio::execution::relationship.continuation)
* ... @endcode
*/
static BOOST_ASIO_CONSTEXPR execution::relationship_t query(
execution::relationship_t) BOOST_ASIO_NOEXCEPT
{
return Relationship();
}
/// Query the current value of the @c allocator property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* auto alloc = boost::asio::query(ex,
* boost::asio::execution::allocator); @endcode
*/
template
BOOST_ASIO_CONSTEXPR Allocator query(
execution::allocator_t) const BOOST_ASIO_NOEXCEPT
{
return allocator_;
}
/// Query the current value of the @c allocator property.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* auto alloc = boost::asio::query(ex,
* boost::asio::execution::allocator); @endcode
*/
BOOST_ASIO_CONSTEXPR Allocator query(
execution::allocator_t) const BOOST_ASIO_NOEXCEPT
{
return allocator_;
}
/// Query the occupancy (recommended number of work items) for the system
/// context.
/**
* Do not call this function directly. It is intended for use with the
* boost::asio::query customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* std::size_t occupancy = boost::asio::query(
* ex, boost::asio::execution::occupancy); @endcode
*/
std::size_t query(execution::occupancy_t) const BOOST_ASIO_NOEXCEPT;
/// Compare two executors for equality.
/**
* Two executors are equal if they refer to the same underlying io_context.
*/
friend bool operator==(const basic_system_executor&,
const basic_system_executor&) BOOST_ASIO_NOEXCEPT
{
return true;
}
/// Compare two executors for inequality.
/**
* Two executors are equal if they refer to the same underlying io_context.
*/
friend bool operator!=(const basic_system_executor&,
const basic_system_executor&) BOOST_ASIO_NOEXCEPT
{
return false;
}
/// Execution function.
/**
* Do not call this function directly. It is intended for use with the
* execution::execute customisation point.
*
* For example:
* @code boost::asio::system_executor ex;
* execution::execute(ex, my_function_object); @endcode
*/
template
void execute(BOOST_ASIO_MOVE_ARG(Function) f) const
{
this->do_execute(BOOST_ASIO_MOVE_CAST(Function)(f), Blocking());
}
#if !defined(BOOST_ASIO_NO_TS_EXECUTORS)
/// Obtain the underlying execution context.
system_context& context() const BOOST_ASIO_NOEXCEPT;
/// Inform the executor that it has some outstanding work to do.
/**
* For the system executor, this is a no-op.
*/
void on_work_started() const BOOST_ASIO_NOEXCEPT
{
}
/// Inform the executor that some work is no longer outstanding.
/**
* For the system executor, this is a no-op.
*/
void on_work_finished() const BOOST_ASIO_NOEXCEPT
{
}
/// Request the system executor to invoke the given function object.
/**
* This function is used to ask the executor to execute the given function
* object. The function object will always be executed inside this function.
*
* @param f The function object to be called. The executor will make
* a copy of the handler object as required. The function signature of the
* function object must be: @code void function(); @endcode
*
* @param a An allocator that may be used by the executor to allocate the
* internal storage needed for function invocation.
*/
template
void dispatch(BOOST_ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const;
/// Request the system executor to invoke the given function object.
/**
* This function is used to ask the executor to execute the given function
* object. The function object will never be executed inside this function.
* Instead, it will be scheduled to run on an unspecified system thread pool.
*
* @param f The function object to be called. The executor will make
* a copy of the handler object as required. The function signature of the
* function object must be: @code void function(); @endcode
*
* @param a An allocator that may be used by the executor to allocate the
* internal storage needed for function invocation.
*/
template
void post(BOOST_ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const;
/// Request the system executor to invoke the given function object.
/**
* This function is used to ask the executor to execute the given function
* object. The function object will never be executed inside this function.
* Instead, it will be scheduled to run on an unspecified system thread pool.
*
* @param f The function object to be called. The executor will make
* a copy of the handler object as required. The function signature of the
* function object must be: @code void function(); @endcode
*
* @param a An allocator that may be used by the executor to allocate the
* internal storage needed for function invocation.
*/
template
void defer(BOOST_ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const;
#endif // !defined(BOOST_ASIO_NO_TS_EXECUTORS)
private:
template friend class basic_system_executor;
// Constructor used by require().
basic_system_executor(const Allocator& a)
: allocator_(a)
{
}
/// Execution helper implementation for the possibly blocking property.
template
void do_execute(BOOST_ASIO_MOVE_ARG(Function) f,
execution::blocking_t::possibly_t) const;
/// Execution helper implementation for the always blocking property.
template
void do_execute(BOOST_ASIO_MOVE_ARG(Function) f,
execution::blocking_t::always_t) const;
/// Execution helper implementation for the never blocking property.
template
void do_execute(BOOST_ASIO_MOVE_ARG(Function) f,
execution::blocking_t::never_t) const;
// The allocator used for execution functions.
Allocator allocator_;
};
/// An executor that uses arbitrary threads.
/**
* The system executor represents an execution context where functions are
* permitted to run on arbitrary threads. When the blocking.never property is
* established, the system executor will schedule the function to run on an
* unspecified system thread pool. When either blocking.possibly or
* blocking.always is established, the executor invokes the function
* immediately.
*/
typedef basic_system_executor >
system_executor;
#if !defined(GENERATING_DOCUMENTATION)
namespace traits {
#if !defined(BOOST_ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
template
struct equality_comparable<
boost::asio::basic_system_executor
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
};
#endif // !defined(BOOST_ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
#if !defined(BOOST_ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
template
struct execute_member<
boost::asio::basic_system_executor,
Function
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef void result_type;
};
#endif // !defined(BOOST_ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
#if !defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::blocking_t::possibly_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor<
boost::asio::execution::blocking_t::possibly_t,
Relationship, Allocator> result_type;
};
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::blocking_t::always_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor<
boost::asio::execution::blocking_t::always_t,
Relationship, Allocator> result_type;
};
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::blocking_t::never_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor<
boost::asio::execution::blocking_t::never_t,
Relationship, Allocator> result_type;
};
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::relationship_t::fork_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor result_type;
};
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::relationship_t::continuation_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor result_type;
};
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::allocator_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor > result_type;
};
template
struct require_member<
boost::asio::basic_system_executor,
boost::asio::execution::allocator_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
typedef boost::asio::basic_system_executor result_type;
};
#endif // !defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
#if !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
template
struct query_static_constexpr_member<
boost::asio::basic_system_executor,
Property,
typename boost::asio::enable_if<
boost::asio::is_convertible<
Property,
boost::asio::execution::mapping_t
>::value
>::type
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
typedef boost::asio::execution::mapping_t::thread_t result_type;
static BOOST_ASIO_CONSTEXPR result_type value() BOOST_ASIO_NOEXCEPT
{
return result_type();
}
};
#endif // !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
#if !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
template
struct query_member<
boost::asio::basic_system_executor,
Property,
typename boost::asio::enable_if<
boost::asio::is_convertible<
Property,
boost::asio::execution::blocking_t
>::value
>::type
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
typedef boost::asio::execution::blocking_t result_type;
};
template
struct query_member<
boost::asio::basic_system_executor,
Property,
typename boost::asio::enable_if<
boost::asio::is_convertible<
Property,
boost::asio::execution::relationship_t
>::value
>::type
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
typedef boost::asio::execution::relationship_t result_type;
};
template
struct query_member<
boost::asio::basic_system_executor,
boost::asio::execution::context_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
typedef boost::asio::system_context& result_type;
};
template
struct query_member<
boost::asio::basic_system_executor,
boost::asio::execution::allocator_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
typedef Allocator result_type;
};
template
struct query_member<
boost::asio::basic_system_executor,
boost::asio::execution::allocator_t
>
{
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
typedef Allocator result_type;
};
#endif // !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
} // namespace traits
#endif // !defined(GENERATING_DOCUMENTATION)
} // namespace asio
} // namespace boost
#include
#include
#endif // BOOST_ASIO_SYSTEM_EXECUTOR_HPP