mirror of
https://github.com/KolibriOS/kolibrios.git
synced 2024-12-16 11:52:34 +03:00
1554 lines
41 KiB
C++
1554 lines
41 KiB
C++
// <future> -*- C++ -*-
|
|
|
|
// Copyright (C) 2009-2013 Free Software Foundation, Inc.
|
|
//
|
|
// This file is part of the GNU ISO C++ Library. This library is free
|
|
// software; you can redistribute it and/or modify it under the
|
|
// terms of the GNU General Public License as published by the
|
|
// Free Software Foundation; either version 3, or (at your option)
|
|
// any later version.
|
|
|
|
// This library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// Under Section 7 of GPL version 3, you are granted additional
|
|
// permissions described in the GCC Runtime Library Exception, version
|
|
// 3.1, as published by the Free Software Foundation.
|
|
|
|
// You should have received a copy of the GNU General Public License and
|
|
// a copy of the GCC Runtime Library Exception along with this program;
|
|
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
// <http://www.gnu.org/licenses/>.
|
|
|
|
/** @file include/future
|
|
* This is a Standard C++ Library header.
|
|
*/
|
|
|
|
#ifndef _GLIBCXX_FUTURE
|
|
#define _GLIBCXX_FUTURE 1
|
|
|
|
#pragma GCC system_header
|
|
|
|
#if __cplusplus < 201103L
|
|
# include <bits/c++0x_warning.h>
|
|
#else
|
|
|
|
#include <functional>
|
|
#include <mutex>
|
|
#include <thread>
|
|
#include <condition_variable>
|
|
#include <system_error>
|
|
#include <atomic>
|
|
#include <bits/functexcept.h>
|
|
#include <bits/unique_ptr.h>
|
|
#include <bits/shared_ptr.h>
|
|
#include <bits/uses_allocator.h>
|
|
#include <bits/alloc_traits.h>
|
|
|
|
namespace std _GLIBCXX_VISIBILITY(default)
|
|
{
|
|
_GLIBCXX_BEGIN_NAMESPACE_VERSION
|
|
|
|
/**
|
|
* @defgroup futures Futures
|
|
* @ingroup concurrency
|
|
*
|
|
* Classes for futures support.
|
|
* @{
|
|
*/
|
|
|
|
/// Error code for futures
|
|
enum class future_errc
|
|
{
|
|
future_already_retrieved = 1,
|
|
promise_already_satisfied,
|
|
no_state,
|
|
broken_promise
|
|
};
|
|
|
|
/// Specialization.
|
|
template<>
|
|
struct is_error_code_enum<future_errc> : public true_type { };
|
|
|
|
/// Points to a statically-allocated object derived from error_category.
|
|
const error_category&
|
|
future_category() noexcept;
|
|
|
|
/// Overload for make_error_code.
|
|
inline error_code
|
|
make_error_code(future_errc __errc) noexcept
|
|
{ return error_code(static_cast<int>(__errc), future_category()); }
|
|
|
|
/// Overload for make_error_condition.
|
|
inline error_condition
|
|
make_error_condition(future_errc __errc) noexcept
|
|
{ return error_condition(static_cast<int>(__errc), future_category()); }
|
|
|
|
/**
|
|
* @brief Exception type thrown by futures.
|
|
* @ingroup exceptions
|
|
*/
|
|
class future_error : public logic_error
|
|
{
|
|
error_code _M_code;
|
|
|
|
public:
|
|
explicit future_error(error_code __ec)
|
|
: logic_error("std::future_error"), _M_code(__ec)
|
|
{ }
|
|
|
|
virtual ~future_error() noexcept;
|
|
|
|
virtual const char*
|
|
what() const noexcept;
|
|
|
|
const error_code&
|
|
code() const noexcept { return _M_code; }
|
|
};
|
|
|
|
// Forward declarations.
|
|
template<typename _Res>
|
|
class future;
|
|
|
|
template<typename _Res>
|
|
class shared_future;
|
|
|
|
template<typename _Signature>
|
|
class packaged_task;
|
|
|
|
template<typename _Res>
|
|
class promise;
|
|
|
|
/// Launch code for futures
|
|
enum class launch
|
|
{
|
|
async = 1,
|
|
deferred = 2
|
|
};
|
|
|
|
constexpr launch operator&(launch __x, launch __y)
|
|
{
|
|
return static_cast<launch>(
|
|
static_cast<int>(__x) & static_cast<int>(__y));
|
|
}
|
|
|
|
constexpr launch operator|(launch __x, launch __y)
|
|
{
|
|
return static_cast<launch>(
|
|
static_cast<int>(__x) | static_cast<int>(__y));
|
|
}
|
|
|
|
constexpr launch operator^(launch __x, launch __y)
|
|
{
|
|
return static_cast<launch>(
|
|
static_cast<int>(__x) ^ static_cast<int>(__y));
|
|
}
|
|
|
|
constexpr launch operator~(launch __x)
|
|
{ return static_cast<launch>(~static_cast<int>(__x)); }
|
|
|
|
inline launch& operator&=(launch& __x, launch __y)
|
|
{ return __x = __x & __y; }
|
|
|
|
inline launch& operator|=(launch& __x, launch __y)
|
|
{ return __x = __x | __y; }
|
|
|
|
inline launch& operator^=(launch& __x, launch __y)
|
|
{ return __x = __x ^ __y; }
|
|
|
|
/// Status code for futures
|
|
enum class future_status
|
|
{
|
|
ready,
|
|
timeout,
|
|
deferred
|
|
};
|
|
|
|
template<typename _Fn, typename... _Args>
|
|
future<typename result_of<_Fn(_Args...)>::type>
|
|
async(launch __policy, _Fn&& __fn, _Args&&... __args);
|
|
|
|
template<typename _Fn, typename... _Args>
|
|
future<typename result_of<_Fn(_Args...)>::type>
|
|
async(_Fn&& __fn, _Args&&... __args);
|
|
|
|
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) \
|
|
&& (ATOMIC_INT_LOCK_FREE > 1)
|
|
|
|
/// Base class and enclosing scope.
|
|
struct __future_base
|
|
{
|
|
/// Base class for results.
|
|
struct _Result_base
|
|
{
|
|
exception_ptr _M_error;
|
|
|
|
_Result_base(const _Result_base&) = delete;
|
|
_Result_base& operator=(const _Result_base&) = delete;
|
|
|
|
// _M_destroy() allows derived classes to control deallocation
|
|
virtual void _M_destroy() = 0;
|
|
|
|
struct _Deleter
|
|
{
|
|
void operator()(_Result_base* __fr) const { __fr->_M_destroy(); }
|
|
};
|
|
|
|
protected:
|
|
_Result_base();
|
|
virtual ~_Result_base();
|
|
};
|
|
|
|
/// Result.
|
|
template<typename _Res>
|
|
struct _Result : _Result_base
|
|
{
|
|
private:
|
|
typedef alignment_of<_Res> __a_of;
|
|
typedef aligned_storage<sizeof(_Res), __a_of::value> __align_storage;
|
|
typedef typename __align_storage::type __align_type;
|
|
|
|
__align_type _M_storage;
|
|
bool _M_initialized;
|
|
|
|
public:
|
|
typedef _Res result_type;
|
|
|
|
_Result() noexcept : _M_initialized() { }
|
|
|
|
~_Result()
|
|
{
|
|
if (_M_initialized)
|
|
_M_value().~_Res();
|
|
}
|
|
|
|
// Return lvalue, future will add const or rvalue-reference
|
|
_Res&
|
|
_M_value() noexcept { return *static_cast<_Res*>(_M_addr()); }
|
|
|
|
void
|
|
_M_set(const _Res& __res)
|
|
{
|
|
::new (_M_addr()) _Res(__res);
|
|
_M_initialized = true;
|
|
}
|
|
|
|
void
|
|
_M_set(_Res&& __res)
|
|
{
|
|
::new (_M_addr()) _Res(std::move(__res));
|
|
_M_initialized = true;
|
|
}
|
|
|
|
private:
|
|
void _M_destroy() { delete this; }
|
|
|
|
void* _M_addr() noexcept { return static_cast<void*>(&_M_storage); }
|
|
};
|
|
|
|
/// A unique_ptr based on the instantiating type.
|
|
template<typename _Res>
|
|
using _Ptr = unique_ptr<_Res, _Result_base::_Deleter>;
|
|
|
|
/// Result_alloc.
|
|
template<typename _Res, typename _Alloc>
|
|
struct _Result_alloc final : _Result<_Res>, _Alloc
|
|
{
|
|
typedef typename allocator_traits<_Alloc>::template
|
|
rebind_alloc<_Result_alloc> __allocator_type;
|
|
|
|
explicit
|
|
_Result_alloc(const _Alloc& __a) : _Result<_Res>(), _Alloc(__a)
|
|
{ }
|
|
|
|
private:
|
|
void _M_destroy()
|
|
{
|
|
typedef allocator_traits<__allocator_type> __traits;
|
|
__allocator_type __a(*this);
|
|
__traits::destroy(__a, this);
|
|
__traits::deallocate(__a, this, 1);
|
|
}
|
|
};
|
|
|
|
template<typename _Res, typename _Allocator>
|
|
static _Ptr<_Result_alloc<_Res, _Allocator>>
|
|
_S_allocate_result(const _Allocator& __a)
|
|
{
|
|
typedef _Result_alloc<_Res, _Allocator> __result_type;
|
|
typedef allocator_traits<typename __result_type::__allocator_type>
|
|
__traits;
|
|
typename __traits::allocator_type __a2(__a);
|
|
__result_type* __p = __traits::allocate(__a2, 1);
|
|
__try
|
|
{
|
|
__traits::construct(__a2, __p, __a);
|
|
}
|
|
__catch(...)
|
|
{
|
|
__traits::deallocate(__a2, __p, 1);
|
|
__throw_exception_again;
|
|
}
|
|
return _Ptr<__result_type>(__p);
|
|
}
|
|
|
|
template<typename _Res, typename _Tp>
|
|
static _Ptr<_Result<_Res>>
|
|
_S_allocate_result(const std::allocator<_Tp>& __a)
|
|
{
|
|
return _Ptr<_Result<_Res>>(new _Result<_Res>);
|
|
}
|
|
|
|
/// Base class for state between a promise and one or more
|
|
/// associated futures.
|
|
class _State_base
|
|
{
|
|
typedef _Ptr<_Result_base> _Ptr_type;
|
|
|
|
_Ptr_type _M_result;
|
|
mutex _M_mutex;
|
|
condition_variable _M_cond;
|
|
atomic_flag _M_retrieved;
|
|
once_flag _M_once;
|
|
|
|
public:
|
|
_State_base() noexcept : _M_result(), _M_retrieved(ATOMIC_FLAG_INIT) { }
|
|
_State_base(const _State_base&) = delete;
|
|
_State_base& operator=(const _State_base&) = delete;
|
|
virtual ~_State_base();
|
|
|
|
_Result_base&
|
|
wait()
|
|
{
|
|
_M_run_deferred();
|
|
unique_lock<mutex> __lock(_M_mutex);
|
|
_M_cond.wait(__lock, [&] { return _M_ready(); });
|
|
return *_M_result;
|
|
}
|
|
|
|
template<typename _Rep, typename _Period>
|
|
future_status
|
|
wait_for(const chrono::duration<_Rep, _Period>& __rel)
|
|
{
|
|
unique_lock<mutex> __lock(_M_mutex);
|
|
if (_M_cond.wait_for(__lock, __rel, [&] { return _M_ready(); }))
|
|
return future_status::ready;
|
|
return future_status::timeout;
|
|
}
|
|
|
|
template<typename _Clock, typename _Duration>
|
|
future_status
|
|
wait_until(const chrono::time_point<_Clock, _Duration>& __abs)
|
|
{
|
|
unique_lock<mutex> __lock(_M_mutex);
|
|
if (_M_cond.wait_until(__lock, __abs, [&] { return _M_ready(); }))
|
|
return future_status::ready;
|
|
return future_status::timeout;
|
|
}
|
|
|
|
void
|
|
_M_set_result(function<_Ptr_type()> __res, bool __ignore_failure = false)
|
|
{
|
|
bool __set = __ignore_failure;
|
|
// all calls to this function are serialized,
|
|
// side-effects of invoking __res only happen once
|
|
call_once(_M_once, &_State_base::_M_do_set, this, ref(__res),
|
|
ref(__set));
|
|
if (!__set)
|
|
__throw_future_error(int(future_errc::promise_already_satisfied));
|
|
}
|
|
|
|
void
|
|
_M_break_promise(_Ptr_type __res)
|
|
{
|
|
if (static_cast<bool>(__res))
|
|
{
|
|
error_code __ec(make_error_code(future_errc::broken_promise));
|
|
__res->_M_error = copy_exception(future_error(__ec));
|
|
{
|
|
lock_guard<mutex> __lock(_M_mutex);
|
|
_M_result.swap(__res);
|
|
}
|
|
_M_cond.notify_all();
|
|
}
|
|
}
|
|
|
|
// Called when this object is passed to a future.
|
|
void
|
|
_M_set_retrieved_flag()
|
|
{
|
|
if (_M_retrieved.test_and_set())
|
|
__throw_future_error(int(future_errc::future_already_retrieved));
|
|
}
|
|
|
|
template<typename _Res, typename _Arg>
|
|
struct _Setter;
|
|
|
|
// set lvalues
|
|
template<typename _Res, typename _Arg>
|
|
struct _Setter<_Res, _Arg&>
|
|
{
|
|
// check this is only used by promise<R>::set_value(const R&)
|
|
// or promise<R>::set_value(R&)
|
|
static_assert(is_same<_Res, _Arg&>::value // promise<R&>
|
|
|| is_same<const _Res, _Arg>::value, // promise<R>
|
|
"Invalid specialisation");
|
|
|
|
typename promise<_Res>::_Ptr_type operator()()
|
|
{
|
|
_State_base::_S_check(_M_promise->_M_future);
|
|
_M_promise->_M_storage->_M_set(_M_arg);
|
|
return std::move(_M_promise->_M_storage);
|
|
}
|
|
promise<_Res>* _M_promise;
|
|
_Arg& _M_arg;
|
|
};
|
|
|
|
// set rvalues
|
|
template<typename _Res>
|
|
struct _Setter<_Res, _Res&&>
|
|
{
|
|
typename promise<_Res>::_Ptr_type operator()()
|
|
{
|
|
_State_base::_S_check(_M_promise->_M_future);
|
|
_M_promise->_M_storage->_M_set(std::move(_M_arg));
|
|
return std::move(_M_promise->_M_storage);
|
|
}
|
|
promise<_Res>* _M_promise;
|
|
_Res& _M_arg;
|
|
};
|
|
|
|
struct __exception_ptr_tag { };
|
|
|
|
// set exceptions
|
|
template<typename _Res>
|
|
struct _Setter<_Res, __exception_ptr_tag>
|
|
{
|
|
typename promise<_Res>::_Ptr_type operator()()
|
|
{
|
|
_State_base::_S_check(_M_promise->_M_future);
|
|
_M_promise->_M_storage->_M_error = _M_ex;
|
|
return std::move(_M_promise->_M_storage);
|
|
}
|
|
|
|
promise<_Res>* _M_promise;
|
|
exception_ptr& _M_ex;
|
|
};
|
|
|
|
template<typename _Res, typename _Arg>
|
|
static _Setter<_Res, _Arg&&>
|
|
__setter(promise<_Res>* __prom, _Arg&& __arg)
|
|
{
|
|
return _Setter<_Res, _Arg&&>{ __prom, __arg };
|
|
}
|
|
|
|
template<typename _Res>
|
|
static _Setter<_Res, __exception_ptr_tag>
|
|
__setter(exception_ptr& __ex, promise<_Res>* __prom)
|
|
{
|
|
return _Setter<_Res, __exception_ptr_tag>{ __prom, __ex };
|
|
}
|
|
|
|
static _Setter<void, void>
|
|
__setter(promise<void>* __prom);
|
|
|
|
template<typename _Tp>
|
|
static void
|
|
_S_check(const shared_ptr<_Tp>& __p)
|
|
{
|
|
if (!static_cast<bool>(__p))
|
|
__throw_future_error((int)future_errc::no_state);
|
|
}
|
|
|
|
private:
|
|
void
|
|
_M_do_set(function<_Ptr_type()>& __f, bool& __set)
|
|
{
|
|
_Ptr_type __res = __f();
|
|
{
|
|
lock_guard<mutex> __lock(_M_mutex);
|
|
_M_result.swap(__res);
|
|
}
|
|
_M_cond.notify_all();
|
|
__set = true;
|
|
}
|
|
|
|
bool _M_ready() const noexcept { return static_cast<bool>(_M_result); }
|
|
|
|
// Misnamed: waits for completion of async function.
|
|
virtual void _M_run_deferred() { }
|
|
};
|
|
|
|
template<typename _BoundFn, typename = typename _BoundFn::result_type>
|
|
class _Deferred_state;
|
|
|
|
class _Async_state_common;
|
|
|
|
template<typename _BoundFn, typename = typename _BoundFn::result_type>
|
|
class _Async_state_impl;
|
|
|
|
template<typename _Signature>
|
|
class _Task_state_base;
|
|
|
|
template<typename _Fn, typename _Alloc, typename _Signature>
|
|
class _Task_state;
|
|
|
|
template<typename _BoundFn>
|
|
static std::shared_ptr<_State_base>
|
|
_S_make_deferred_state(_BoundFn&& __fn);
|
|
|
|
template<typename _BoundFn>
|
|
static std::shared_ptr<_State_base>
|
|
_S_make_async_state(_BoundFn&& __fn);
|
|
|
|
template<typename _Res_ptr,
|
|
typename _Res = typename _Res_ptr::element_type::result_type>
|
|
struct _Task_setter;
|
|
|
|
template<typename _Res_ptr, typename _BoundFn>
|
|
static _Task_setter<_Res_ptr>
|
|
_S_task_setter(_Res_ptr& __ptr, _BoundFn&& __call)
|
|
{
|
|
return _Task_setter<_Res_ptr>{ __ptr, std::ref(__call) };
|
|
}
|
|
};
|
|
|
|
/// Partial specialization for reference types.
|
|
template<typename _Res>
|
|
struct __future_base::_Result<_Res&> : __future_base::_Result_base
|
|
{
|
|
typedef _Res& result_type;
|
|
|
|
_Result() noexcept : _M_value_ptr() { }
|
|
|
|
void _M_set(_Res& __res) noexcept { _M_value_ptr = &__res; }
|
|
|
|
_Res& _M_get() noexcept { return *_M_value_ptr; }
|
|
|
|
private:
|
|
_Res* _M_value_ptr;
|
|
|
|
void _M_destroy() { delete this; }
|
|
};
|
|
|
|
/// Explicit specialization for void.
|
|
template<>
|
|
struct __future_base::_Result<void> : __future_base::_Result_base
|
|
{
|
|
typedef void result_type;
|
|
|
|
private:
|
|
void _M_destroy() { delete this; }
|
|
};
|
|
|
|
|
|
/// Common implementation for future and shared_future.
|
|
template<typename _Res>
|
|
class __basic_future : public __future_base
|
|
{
|
|
protected:
|
|
typedef shared_ptr<_State_base> __state_type;
|
|
typedef __future_base::_Result<_Res>& __result_type;
|
|
|
|
private:
|
|
__state_type _M_state;
|
|
|
|
public:
|
|
// Disable copying.
|
|
__basic_future(const __basic_future&) = delete;
|
|
__basic_future& operator=(const __basic_future&) = delete;
|
|
|
|
bool
|
|
valid() const noexcept { return static_cast<bool>(_M_state); }
|
|
|
|
void
|
|
wait() const
|
|
{
|
|
_State_base::_S_check(_M_state);
|
|
_M_state->wait();
|
|
}
|
|
|
|
template<typename _Rep, typename _Period>
|
|
future_status
|
|
wait_for(const chrono::duration<_Rep, _Period>& __rel) const
|
|
{
|
|
_State_base::_S_check(_M_state);
|
|
return _M_state->wait_for(__rel);
|
|
}
|
|
|
|
template<typename _Clock, typename _Duration>
|
|
future_status
|
|
wait_until(const chrono::time_point<_Clock, _Duration>& __abs) const
|
|
{
|
|
_State_base::_S_check(_M_state);
|
|
return _M_state->wait_until(__abs);
|
|
}
|
|
|
|
protected:
|
|
/// Wait for the state to be ready and rethrow any stored exception
|
|
__result_type
|
|
_M_get_result() const
|
|
{
|
|
_State_base::_S_check(_M_state);
|
|
_Result_base& __res = _M_state->wait();
|
|
if (!(__res._M_error == 0))
|
|
rethrow_exception(__res._M_error);
|
|
return static_cast<__result_type>(__res);
|
|
}
|
|
|
|
void _M_swap(__basic_future& __that) noexcept
|
|
{
|
|
_M_state.swap(__that._M_state);
|
|
}
|
|
|
|
// Construction of a future by promise::get_future()
|
|
explicit
|
|
__basic_future(const __state_type& __state) : _M_state(__state)
|
|
{
|
|
_State_base::_S_check(_M_state);
|
|
_M_state->_M_set_retrieved_flag();
|
|
}
|
|
|
|
// Copy construction from a shared_future
|
|
explicit
|
|
__basic_future(const shared_future<_Res>&) noexcept;
|
|
|
|
// Move construction from a shared_future
|
|
explicit
|
|
__basic_future(shared_future<_Res>&&) noexcept;
|
|
|
|
// Move construction from a future
|
|
explicit
|
|
__basic_future(future<_Res>&&) noexcept;
|
|
|
|
constexpr __basic_future() noexcept : _M_state() { }
|
|
|
|
struct _Reset
|
|
{
|
|
explicit _Reset(__basic_future& __fut) noexcept : _M_fut(__fut) { }
|
|
~_Reset() { _M_fut._M_state.reset(); }
|
|
__basic_future& _M_fut;
|
|
};
|
|
};
|
|
|
|
|
|
/// Primary template for future.
|
|
template<typename _Res>
|
|
class future : public __basic_future<_Res>
|
|
{
|
|
friend class promise<_Res>;
|
|
template<typename> friend class packaged_task;
|
|
template<typename _Fn, typename... _Args>
|
|
friend future<typename result_of<_Fn(_Args...)>::type>
|
|
async(launch, _Fn&&, _Args&&...);
|
|
|
|
typedef __basic_future<_Res> _Base_type;
|
|
typedef typename _Base_type::__state_type __state_type;
|
|
|
|
explicit
|
|
future(const __state_type& __state) : _Base_type(__state) { }
|
|
|
|
public:
|
|
constexpr future() noexcept : _Base_type() { }
|
|
|
|
/// Move constructor
|
|
future(future&& __uf) noexcept : _Base_type(std::move(__uf)) { }
|
|
|
|
// Disable copying
|
|
future(const future&) = delete;
|
|
future& operator=(const future&) = delete;
|
|
|
|
future& operator=(future&& __fut) noexcept
|
|
{
|
|
future(std::move(__fut))._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
/// Retrieving the value
|
|
_Res
|
|
get()
|
|
{
|
|
typename _Base_type::_Reset __reset(*this);
|
|
return std::move(this->_M_get_result()._M_value());
|
|
}
|
|
|
|
shared_future<_Res> share();
|
|
};
|
|
|
|
/// Partial specialization for future<R&>
|
|
template<typename _Res>
|
|
class future<_Res&> : public __basic_future<_Res&>
|
|
{
|
|
friend class promise<_Res&>;
|
|
template<typename> friend class packaged_task;
|
|
template<typename _Fn, typename... _Args>
|
|
friend future<typename result_of<_Fn(_Args...)>::type>
|
|
async(launch, _Fn&&, _Args&&...);
|
|
|
|
typedef __basic_future<_Res&> _Base_type;
|
|
typedef typename _Base_type::__state_type __state_type;
|
|
|
|
explicit
|
|
future(const __state_type& __state) : _Base_type(__state) { }
|
|
|
|
public:
|
|
constexpr future() noexcept : _Base_type() { }
|
|
|
|
/// Move constructor
|
|
future(future&& __uf) noexcept : _Base_type(std::move(__uf)) { }
|
|
|
|
// Disable copying
|
|
future(const future&) = delete;
|
|
future& operator=(const future&) = delete;
|
|
|
|
future& operator=(future&& __fut) noexcept
|
|
{
|
|
future(std::move(__fut))._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
/// Retrieving the value
|
|
_Res&
|
|
get()
|
|
{
|
|
typename _Base_type::_Reset __reset(*this);
|
|
return this->_M_get_result()._M_get();
|
|
}
|
|
|
|
shared_future<_Res&> share();
|
|
};
|
|
|
|
/// Explicit specialization for future<void>
|
|
template<>
|
|
class future<void> : public __basic_future<void>
|
|
{
|
|
friend class promise<void>;
|
|
template<typename> friend class packaged_task;
|
|
template<typename _Fn, typename... _Args>
|
|
friend future<typename result_of<_Fn(_Args...)>::type>
|
|
async(launch, _Fn&&, _Args&&...);
|
|
|
|
typedef __basic_future<void> _Base_type;
|
|
typedef typename _Base_type::__state_type __state_type;
|
|
|
|
explicit
|
|
future(const __state_type& __state) : _Base_type(__state) { }
|
|
|
|
public:
|
|
constexpr future() noexcept : _Base_type() { }
|
|
|
|
/// Move constructor
|
|
future(future&& __uf) noexcept : _Base_type(std::move(__uf)) { }
|
|
|
|
// Disable copying
|
|
future(const future&) = delete;
|
|
future& operator=(const future&) = delete;
|
|
|
|
future& operator=(future&& __fut) noexcept
|
|
{
|
|
future(std::move(__fut))._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
/// Retrieving the value
|
|
void
|
|
get()
|
|
{
|
|
typename _Base_type::_Reset __reset(*this);
|
|
this->_M_get_result();
|
|
}
|
|
|
|
shared_future<void> share();
|
|
};
|
|
|
|
|
|
/// Primary template for shared_future.
|
|
template<typename _Res>
|
|
class shared_future : public __basic_future<_Res>
|
|
{
|
|
typedef __basic_future<_Res> _Base_type;
|
|
|
|
public:
|
|
constexpr shared_future() noexcept : _Base_type() { }
|
|
|
|
/// Copy constructor
|
|
shared_future(const shared_future& __sf) : _Base_type(__sf) { }
|
|
|
|
/// Construct from a future rvalue
|
|
shared_future(future<_Res>&& __uf) noexcept
|
|
: _Base_type(std::move(__uf))
|
|
{ }
|
|
|
|
/// Construct from a shared_future rvalue
|
|
shared_future(shared_future&& __sf) noexcept
|
|
: _Base_type(std::move(__sf))
|
|
{ }
|
|
|
|
shared_future& operator=(const shared_future& __sf)
|
|
{
|
|
shared_future(__sf)._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
shared_future& operator=(shared_future&& __sf) noexcept
|
|
{
|
|
shared_future(std::move(__sf))._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
/// Retrieving the value
|
|
const _Res&
|
|
get() const { return this->_M_get_result()._M_value(); }
|
|
};
|
|
|
|
/// Partial specialization for shared_future<R&>
|
|
template<typename _Res>
|
|
class shared_future<_Res&> : public __basic_future<_Res&>
|
|
{
|
|
typedef __basic_future<_Res&> _Base_type;
|
|
|
|
public:
|
|
constexpr shared_future() noexcept : _Base_type() { }
|
|
|
|
/// Copy constructor
|
|
shared_future(const shared_future& __sf) : _Base_type(__sf) { }
|
|
|
|
/// Construct from a future rvalue
|
|
shared_future(future<_Res&>&& __uf) noexcept
|
|
: _Base_type(std::move(__uf))
|
|
{ }
|
|
|
|
/// Construct from a shared_future rvalue
|
|
shared_future(shared_future&& __sf) noexcept
|
|
: _Base_type(std::move(__sf))
|
|
{ }
|
|
|
|
shared_future& operator=(const shared_future& __sf)
|
|
{
|
|
shared_future(__sf)._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
shared_future& operator=(shared_future&& __sf) noexcept
|
|
{
|
|
shared_future(std::move(__sf))._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
/// Retrieving the value
|
|
_Res&
|
|
get() const { return this->_M_get_result()._M_get(); }
|
|
};
|
|
|
|
/// Explicit specialization for shared_future<void>
|
|
template<>
|
|
class shared_future<void> : public __basic_future<void>
|
|
{
|
|
typedef __basic_future<void> _Base_type;
|
|
|
|
public:
|
|
constexpr shared_future() noexcept : _Base_type() { }
|
|
|
|
/// Copy constructor
|
|
shared_future(const shared_future& __sf) : _Base_type(__sf) { }
|
|
|
|
/// Construct from a future rvalue
|
|
shared_future(future<void>&& __uf) noexcept
|
|
: _Base_type(std::move(__uf))
|
|
{ }
|
|
|
|
/// Construct from a shared_future rvalue
|
|
shared_future(shared_future&& __sf) noexcept
|
|
: _Base_type(std::move(__sf))
|
|
{ }
|
|
|
|
shared_future& operator=(const shared_future& __sf)
|
|
{
|
|
shared_future(__sf)._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
shared_future& operator=(shared_future&& __sf) noexcept
|
|
{
|
|
shared_future(std::move(__sf))._M_swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
// Retrieving the value
|
|
void
|
|
get() const { this->_M_get_result(); }
|
|
};
|
|
|
|
// Now we can define the protected __basic_future constructors.
|
|
template<typename _Res>
|
|
inline __basic_future<_Res>::
|
|
__basic_future(const shared_future<_Res>& __sf) noexcept
|
|
: _M_state(__sf._M_state)
|
|
{ }
|
|
|
|
template<typename _Res>
|
|
inline __basic_future<_Res>::
|
|
__basic_future(shared_future<_Res>&& __sf) noexcept
|
|
: _M_state(std::move(__sf._M_state))
|
|
{ }
|
|
|
|
template<typename _Res>
|
|
inline __basic_future<_Res>::
|
|
__basic_future(future<_Res>&& __uf) noexcept
|
|
: _M_state(std::move(__uf._M_state))
|
|
{ }
|
|
|
|
template<typename _Res>
|
|
inline shared_future<_Res>
|
|
future<_Res>::share()
|
|
{ return shared_future<_Res>(std::move(*this)); }
|
|
|
|
template<typename _Res>
|
|
inline shared_future<_Res&>
|
|
future<_Res&>::share()
|
|
{ return shared_future<_Res&>(std::move(*this)); }
|
|
|
|
inline shared_future<void>
|
|
future<void>::share()
|
|
{ return shared_future<void>(std::move(*this)); }
|
|
|
|
/// Primary template for promise
|
|
template<typename _Res>
|
|
class promise
|
|
{
|
|
typedef __future_base::_State_base _State;
|
|
typedef __future_base::_Result<_Res> _Res_type;
|
|
typedef __future_base::_Ptr<_Res_type> _Ptr_type;
|
|
template<typename, typename> friend class _State::_Setter;
|
|
|
|
shared_ptr<_State> _M_future;
|
|
_Ptr_type _M_storage;
|
|
|
|
public:
|
|
promise()
|
|
: _M_future(std::make_shared<_State>()),
|
|
_M_storage(new _Res_type())
|
|
{ }
|
|
|
|
promise(promise&& __rhs) noexcept
|
|
: _M_future(std::move(__rhs._M_future)),
|
|
_M_storage(std::move(__rhs._M_storage))
|
|
{ }
|
|
|
|
template<typename _Allocator>
|
|
promise(allocator_arg_t, const _Allocator& __a)
|
|
: _M_future(std::allocate_shared<_State>(__a)),
|
|
_M_storage(__future_base::_S_allocate_result<_Res>(__a))
|
|
{ }
|
|
|
|
template<typename _Allocator>
|
|
promise(allocator_arg_t, const _Allocator&, promise&& __rhs)
|
|
: _M_future(std::move(__rhs._M_future)),
|
|
_M_storage(std::move(__rhs._M_storage))
|
|
{ }
|
|
|
|
promise(const promise&) = delete;
|
|
|
|
~promise()
|
|
{
|
|
if (static_cast<bool>(_M_future) && !_M_future.unique())
|
|
_M_future->_M_break_promise(std::move(_M_storage));
|
|
}
|
|
|
|
// Assignment
|
|
promise&
|
|
operator=(promise&& __rhs) noexcept
|
|
{
|
|
promise(std::move(__rhs)).swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
promise& operator=(const promise&) = delete;
|
|
|
|
void
|
|
swap(promise& __rhs) noexcept
|
|
{
|
|
_M_future.swap(__rhs._M_future);
|
|
_M_storage.swap(__rhs._M_storage);
|
|
}
|
|
|
|
// Retrieving the result
|
|
future<_Res>
|
|
get_future()
|
|
{ return future<_Res>(_M_future); }
|
|
|
|
// Setting the result
|
|
void
|
|
set_value(const _Res& __r)
|
|
{
|
|
auto __setter = _State::__setter(this, __r);
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
|
|
void
|
|
set_value(_Res&& __r)
|
|
{
|
|
auto __setter = _State::__setter(this, std::move(__r));
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
|
|
void
|
|
set_exception(exception_ptr __p)
|
|
{
|
|
auto __setter = _State::__setter(__p, this);
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
};
|
|
|
|
template<typename _Res>
|
|
inline void
|
|
swap(promise<_Res>& __x, promise<_Res>& __y) noexcept
|
|
{ __x.swap(__y); }
|
|
|
|
template<typename _Res, typename _Alloc>
|
|
struct uses_allocator<promise<_Res>, _Alloc>
|
|
: public true_type { };
|
|
|
|
|
|
/// Partial specialization for promise<R&>
|
|
template<typename _Res>
|
|
class promise<_Res&>
|
|
{
|
|
typedef __future_base::_State_base _State;
|
|
typedef __future_base::_Result<_Res&> _Res_type;
|
|
typedef __future_base::_Ptr<_Res_type> _Ptr_type;
|
|
template<typename, typename> friend class _State::_Setter;
|
|
|
|
shared_ptr<_State> _M_future;
|
|
_Ptr_type _M_storage;
|
|
|
|
public:
|
|
promise()
|
|
: _M_future(std::make_shared<_State>()),
|
|
_M_storage(new _Res_type())
|
|
{ }
|
|
|
|
promise(promise&& __rhs) noexcept
|
|
: _M_future(std::move(__rhs._M_future)),
|
|
_M_storage(std::move(__rhs._M_storage))
|
|
{ }
|
|
|
|
template<typename _Allocator>
|
|
promise(allocator_arg_t, const _Allocator& __a)
|
|
: _M_future(std::allocate_shared<_State>(__a)),
|
|
_M_storage(__future_base::_S_allocate_result<_Res&>(__a))
|
|
{ }
|
|
|
|
template<typename _Allocator>
|
|
promise(allocator_arg_t, const _Allocator&, promise&& __rhs)
|
|
: _M_future(std::move(__rhs._M_future)),
|
|
_M_storage(std::move(__rhs._M_storage))
|
|
{ }
|
|
|
|
promise(const promise&) = delete;
|
|
|
|
~promise()
|
|
{
|
|
if (static_cast<bool>(_M_future) && !_M_future.unique())
|
|
_M_future->_M_break_promise(std::move(_M_storage));
|
|
}
|
|
|
|
// Assignment
|
|
promise&
|
|
operator=(promise&& __rhs) noexcept
|
|
{
|
|
promise(std::move(__rhs)).swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
promise& operator=(const promise&) = delete;
|
|
|
|
void
|
|
swap(promise& __rhs) noexcept
|
|
{
|
|
_M_future.swap(__rhs._M_future);
|
|
_M_storage.swap(__rhs._M_storage);
|
|
}
|
|
|
|
// Retrieving the result
|
|
future<_Res&>
|
|
get_future()
|
|
{ return future<_Res&>(_M_future); }
|
|
|
|
// Setting the result
|
|
void
|
|
set_value(_Res& __r)
|
|
{
|
|
auto __setter = _State::__setter(this, __r);
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
|
|
void
|
|
set_exception(exception_ptr __p)
|
|
{
|
|
auto __setter = _State::__setter(__p, this);
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
};
|
|
|
|
/// Explicit specialization for promise<void>
|
|
template<>
|
|
class promise<void>
|
|
{
|
|
typedef __future_base::_State_base _State;
|
|
typedef __future_base::_Result<void> _Res_type;
|
|
typedef __future_base::_Ptr<_Res_type> _Ptr_type;
|
|
template<typename, typename> friend class _State::_Setter;
|
|
|
|
shared_ptr<_State> _M_future;
|
|
_Ptr_type _M_storage;
|
|
|
|
public:
|
|
promise()
|
|
: _M_future(std::make_shared<_State>()),
|
|
_M_storage(new _Res_type())
|
|
{ }
|
|
|
|
promise(promise&& __rhs) noexcept
|
|
: _M_future(std::move(__rhs._M_future)),
|
|
_M_storage(std::move(__rhs._M_storage))
|
|
{ }
|
|
|
|
template<typename _Allocator>
|
|
promise(allocator_arg_t, const _Allocator& __a)
|
|
: _M_future(std::allocate_shared<_State>(__a)),
|
|
_M_storage(__future_base::_S_allocate_result<void>(__a))
|
|
{ }
|
|
|
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS
|
|
// 2095. missing constructors needed for uses-allocator construction
|
|
template<typename _Allocator>
|
|
promise(allocator_arg_t, const _Allocator&, promise&& __rhs)
|
|
: _M_future(std::move(__rhs._M_future)),
|
|
_M_storage(std::move(__rhs._M_storage))
|
|
{ }
|
|
|
|
promise(const promise&) = delete;
|
|
|
|
~promise()
|
|
{
|
|
if (static_cast<bool>(_M_future) && !_M_future.unique())
|
|
_M_future->_M_break_promise(std::move(_M_storage));
|
|
}
|
|
|
|
// Assignment
|
|
promise&
|
|
operator=(promise&& __rhs) noexcept
|
|
{
|
|
promise(std::move(__rhs)).swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
promise& operator=(const promise&) = delete;
|
|
|
|
void
|
|
swap(promise& __rhs) noexcept
|
|
{
|
|
_M_future.swap(__rhs._M_future);
|
|
_M_storage.swap(__rhs._M_storage);
|
|
}
|
|
|
|
// Retrieving the result
|
|
future<void>
|
|
get_future()
|
|
{ return future<void>(_M_future); }
|
|
|
|
// Setting the result
|
|
void set_value();
|
|
|
|
void
|
|
set_exception(exception_ptr __p)
|
|
{
|
|
auto __setter = _State::__setter(__p, this);
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
};
|
|
|
|
// set void
|
|
template<>
|
|
struct __future_base::_State_base::_Setter<void, void>
|
|
{
|
|
promise<void>::_Ptr_type operator()()
|
|
{
|
|
_State_base::_S_check(_M_promise->_M_future);
|
|
return std::move(_M_promise->_M_storage);
|
|
}
|
|
|
|
promise<void>* _M_promise;
|
|
};
|
|
|
|
inline __future_base::_State_base::_Setter<void, void>
|
|
__future_base::_State_base::__setter(promise<void>* __prom)
|
|
{
|
|
return _Setter<void, void>{ __prom };
|
|
}
|
|
|
|
inline void
|
|
promise<void>::set_value()
|
|
{
|
|
auto __setter = _State::__setter(this);
|
|
_M_future->_M_set_result(std::move(__setter));
|
|
}
|
|
|
|
|
|
template<typename _Ptr_type, typename _Res>
|
|
struct __future_base::_Task_setter
|
|
{
|
|
_Ptr_type operator()()
|
|
{
|
|
__try
|
|
{
|
|
_M_result->_M_set(_M_fn());
|
|
}
|
|
__catch(...)
|
|
{
|
|
_M_result->_M_error = current_exception();
|
|
}
|
|
return std::move(_M_result);
|
|
}
|
|
_Ptr_type& _M_result;
|
|
std::function<_Res()> _M_fn;
|
|
};
|
|
|
|
template<typename _Ptr_type>
|
|
struct __future_base::_Task_setter<_Ptr_type, void>
|
|
{
|
|
_Ptr_type operator()()
|
|
{
|
|
__try
|
|
{
|
|
_M_fn();
|
|
}
|
|
__catch(...)
|
|
{
|
|
_M_result->_M_error = current_exception();
|
|
}
|
|
return std::move(_M_result);
|
|
}
|
|
_Ptr_type& _M_result;
|
|
std::function<void()> _M_fn;
|
|
};
|
|
|
|
template<typename _Res, typename... _Args>
|
|
struct __future_base::_Task_state_base<_Res(_Args...)>
|
|
: __future_base::_State_base
|
|
{
|
|
typedef _Res _Res_type;
|
|
|
|
template<typename _Alloc>
|
|
_Task_state_base(const _Alloc& __a)
|
|
: _M_result(_S_allocate_result<_Res>(__a))
|
|
{ }
|
|
|
|
virtual void
|
|
_M_run(_Args... __args) = 0;
|
|
|
|
virtual shared_ptr<_Task_state_base>
|
|
_M_reset() = 0;
|
|
|
|
typedef __future_base::_Ptr<_Result<_Res>> _Ptr_type;
|
|
_Ptr_type _M_result;
|
|
};
|
|
|
|
template<typename _Fn, typename _Alloc, typename _Res, typename... _Args>
|
|
struct __future_base::_Task_state<_Fn, _Alloc, _Res(_Args...)> final
|
|
: __future_base::_Task_state_base<_Res(_Args...)>
|
|
{
|
|
_Task_state(_Fn&& __fn, const _Alloc& __a)
|
|
: _Task_state_base<_Res(_Args...)>(__a), _M_impl(std::move(__fn), __a)
|
|
{ }
|
|
|
|
private:
|
|
virtual void
|
|
_M_run(_Args... __args)
|
|
{
|
|
// bound arguments decay so wrap lvalue references
|
|
auto __boundfn = std::__bind_simple(std::ref(_M_impl._M_fn),
|
|
_S_maybe_wrap_ref(std::forward<_Args>(__args))...);
|
|
auto __setter = _S_task_setter(this->_M_result, std::move(__boundfn));
|
|
this->_M_set_result(std::move(__setter));
|
|
}
|
|
|
|
virtual shared_ptr<_Task_state_base<_Res(_Args...)>>
|
|
_M_reset();
|
|
|
|
template<typename _Tp>
|
|
static reference_wrapper<_Tp>
|
|
_S_maybe_wrap_ref(_Tp& __t)
|
|
{ return std::ref(__t); }
|
|
|
|
template<typename _Tp>
|
|
static
|
|
typename enable_if<!is_lvalue_reference<_Tp>::value, _Tp>::type&&
|
|
_S_maybe_wrap_ref(_Tp&& __t)
|
|
{ return std::forward<_Tp>(__t); }
|
|
|
|
struct _Impl : _Alloc
|
|
{
|
|
_Impl(_Fn&& __fn, const _Alloc& __a)
|
|
: _Alloc(__a), _M_fn(std::move(__fn)) { }
|
|
_Fn _M_fn;
|
|
} _M_impl;
|
|
};
|
|
|
|
template<typename _Signature, typename _Fn, typename _Alloc>
|
|
static shared_ptr<__future_base::_Task_state_base<_Signature>>
|
|
__create_task_state(_Fn&& __fn, const _Alloc& __a)
|
|
{
|
|
typedef __future_base::_Task_state<_Fn, _Alloc, _Signature> _State;
|
|
return std::allocate_shared<_State>(__a, std::move(__fn), __a);
|
|
}
|
|
|
|
template<typename _Fn, typename _Alloc, typename _Res, typename... _Args>
|
|
shared_ptr<__future_base::_Task_state_base<_Res(_Args...)>>
|
|
__future_base::_Task_state<_Fn, _Alloc, _Res(_Args...)>::_M_reset()
|
|
{
|
|
return __create_task_state<_Res(_Args...)>(std::move(_M_impl._M_fn),
|
|
static_cast<_Alloc&>(_M_impl));
|
|
}
|
|
|
|
template<typename _Task, typename _Fn, bool
|
|
= is_same<_Task, typename decay<_Fn>::type>::value>
|
|
struct __constrain_pkgdtask
|
|
{ typedef void __type; };
|
|
|
|
template<typename _Task, typename _Fn>
|
|
struct __constrain_pkgdtask<_Task, _Fn, true>
|
|
{ };
|
|
|
|
/// packaged_task
|
|
template<typename _Res, typename... _ArgTypes>
|
|
class packaged_task<_Res(_ArgTypes...)>
|
|
{
|
|
typedef __future_base::_Task_state_base<_Res(_ArgTypes...)> _State_type;
|
|
shared_ptr<_State_type> _M_state;
|
|
|
|
public:
|
|
// Construction and destruction
|
|
packaged_task() noexcept { }
|
|
|
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS
|
|
// 2095. missing constructors needed for uses-allocator construction
|
|
template<typename _Allocator>
|
|
packaged_task(allocator_arg_t, const _Allocator& __a) noexcept
|
|
{ }
|
|
|
|
template<typename _Fn, typename = typename
|
|
__constrain_pkgdtask<packaged_task, _Fn>::__type>
|
|
explicit
|
|
packaged_task(_Fn&& __fn)
|
|
: packaged_task(allocator_arg, std::allocator<int>(), std::move(__fn))
|
|
{ }
|
|
|
|
// _GLIBCXX_RESOLVE_LIB_DEFECTS
|
|
// 2097. packaged_task constructors should be constrained
|
|
template<typename _Fn, typename _Alloc, typename = typename
|
|
__constrain_pkgdtask<packaged_task, _Fn>::__type>
|
|
explicit
|
|
packaged_task(allocator_arg_t, const _Alloc& __a, _Fn&& __fn)
|
|
: _M_state(__create_task_state<_Res(_ArgTypes...)>(
|
|
std::forward<_Fn>(__fn), __a))
|
|
{ }
|
|
|
|
~packaged_task()
|
|
{
|
|
if (static_cast<bool>(_M_state) && !_M_state.unique())
|
|
_M_state->_M_break_promise(std::move(_M_state->_M_result));
|
|
}
|
|
|
|
// No copy
|
|
packaged_task(const packaged_task&) = delete;
|
|
packaged_task& operator=(const packaged_task&) = delete;
|
|
|
|
template<typename _Allocator>
|
|
packaged_task(allocator_arg_t, const _Allocator&,
|
|
const packaged_task&) = delete;
|
|
|
|
// Move support
|
|
packaged_task(packaged_task&& __other) noexcept
|
|
{ this->swap(__other); }
|
|
|
|
template<typename _Allocator>
|
|
packaged_task(allocator_arg_t, const _Allocator&,
|
|
packaged_task&& __other) noexcept
|
|
{ this->swap(__other); }
|
|
|
|
packaged_task& operator=(packaged_task&& __other) noexcept
|
|
{
|
|
packaged_task(std::move(__other)).swap(*this);
|
|
return *this;
|
|
}
|
|
|
|
void
|
|
swap(packaged_task& __other) noexcept
|
|
{ _M_state.swap(__other._M_state); }
|
|
|
|
bool
|
|
valid() const noexcept
|
|
{ return static_cast<bool>(_M_state); }
|
|
|
|
// Result retrieval
|
|
future<_Res>
|
|
get_future()
|
|
{ return future<_Res>(_M_state); }
|
|
|
|
// Execution
|
|
void
|
|
operator()(_ArgTypes... __args)
|
|
{
|
|
__future_base::_State_base::_S_check(_M_state);
|
|
_M_state->_M_run(std::forward<_ArgTypes>(__args)...);
|
|
}
|
|
|
|
void
|
|
reset()
|
|
{
|
|
__future_base::_State_base::_S_check(_M_state);
|
|
packaged_task __tmp;
|
|
__tmp._M_state = _M_state;
|
|
_M_state = _M_state->_M_reset();
|
|
}
|
|
};
|
|
|
|
/// swap
|
|
template<typename _Res, typename... _ArgTypes>
|
|
inline void
|
|
swap(packaged_task<_Res(_ArgTypes...)>& __x,
|
|
packaged_task<_Res(_ArgTypes...)>& __y) noexcept
|
|
{ __x.swap(__y); }
|
|
|
|
template<typename _Res, typename _Alloc>
|
|
struct uses_allocator<packaged_task<_Res>, _Alloc>
|
|
: public true_type { };
|
|
|
|
|
|
template<typename _BoundFn, typename _Res>
|
|
class __future_base::_Deferred_state final
|
|
: public __future_base::_State_base
|
|
{
|
|
public:
|
|
explicit
|
|
_Deferred_state(_BoundFn&& __fn)
|
|
: _M_result(new _Result<_Res>()), _M_fn(std::move(__fn))
|
|
{ }
|
|
|
|
private:
|
|
typedef __future_base::_Ptr<_Result<_Res>> _Ptr_type;
|
|
_Ptr_type _M_result;
|
|
_BoundFn _M_fn;
|
|
|
|
virtual void
|
|
_M_run_deferred()
|
|
{
|
|
// safe to call multiple times so ignore failure
|
|
_M_set_result(_S_task_setter(_M_result, _M_fn), true);
|
|
}
|
|
};
|
|
|
|
class __future_base::_Async_state_common : public __future_base::_State_base
|
|
{
|
|
protected:
|
|
#ifdef _GLIBCXX_ASYNC_ABI_COMPAT
|
|
~_Async_state_common();
|
|
#else
|
|
~_Async_state_common() = default;
|
|
#endif
|
|
|
|
// Allow non-timed waiting functions to block until the thread completes,
|
|
// as if joined.
|
|
virtual void _M_run_deferred() { _M_join(); }
|
|
|
|
void _M_join() { std::call_once(_M_once, &thread::join, ref(_M_thread)); }
|
|
|
|
thread _M_thread;
|
|
once_flag _M_once;
|
|
};
|
|
|
|
template<typename _BoundFn, typename _Res>
|
|
class __future_base::_Async_state_impl final
|
|
: public __future_base::_Async_state_common
|
|
{
|
|
public:
|
|
explicit
|
|
_Async_state_impl(_BoundFn&& __fn)
|
|
: _M_result(new _Result<_Res>()), _M_fn(std::move(__fn))
|
|
{
|
|
_M_thread = std::thread{ [this] {
|
|
_M_set_result(_S_task_setter(_M_result, _M_fn));
|
|
} };
|
|
}
|
|
|
|
~_Async_state_impl() { _M_join(); }
|
|
|
|
private:
|
|
typedef __future_base::_Ptr<_Result<_Res>> _Ptr_type;
|
|
_Ptr_type _M_result;
|
|
_BoundFn _M_fn;
|
|
};
|
|
|
|
template<typename _BoundFn>
|
|
inline std::shared_ptr<__future_base::_State_base>
|
|
__future_base::_S_make_deferred_state(_BoundFn&& __fn)
|
|
{
|
|
typedef typename remove_reference<_BoundFn>::type __fn_type;
|
|
typedef _Deferred_state<__fn_type> __state_type;
|
|
return std::make_shared<__state_type>(std::move(__fn));
|
|
}
|
|
|
|
template<typename _BoundFn>
|
|
inline std::shared_ptr<__future_base::_State_base>
|
|
__future_base::_S_make_async_state(_BoundFn&& __fn)
|
|
{
|
|
typedef typename remove_reference<_BoundFn>::type __fn_type;
|
|
typedef _Async_state_impl<__fn_type> __state_type;
|
|
return std::make_shared<__state_type>(std::move(__fn));
|
|
}
|
|
|
|
|
|
/// async
|
|
template<typename _Fn, typename... _Args>
|
|
future<typename result_of<_Fn(_Args...)>::type>
|
|
async(launch __policy, _Fn&& __fn, _Args&&... __args)
|
|
{
|
|
typedef typename result_of<_Fn(_Args...)>::type result_type;
|
|
std::shared_ptr<__future_base::_State_base> __state;
|
|
if ((__policy & (launch::async|launch::deferred)) == launch::async)
|
|
{
|
|
__state = __future_base::_S_make_async_state(std::__bind_simple(
|
|
std::forward<_Fn>(__fn), std::forward<_Args>(__args)...));
|
|
}
|
|
else
|
|
{
|
|
__state = __future_base::_S_make_deferred_state(std::__bind_simple(
|
|
std::forward<_Fn>(__fn), std::forward<_Args>(__args)...));
|
|
}
|
|
return future<result_type>(__state);
|
|
}
|
|
|
|
/// async, potential overload
|
|
template<typename _Fn, typename... _Args>
|
|
inline future<typename result_of<_Fn(_Args...)>::type>
|
|
async(_Fn&& __fn, _Args&&... __args)
|
|
{
|
|
return async(launch::async|launch::deferred, std::forward<_Fn>(__fn),
|
|
std::forward<_Args>(__args)...);
|
|
}
|
|
|
|
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
|
|
// && ATOMIC_INT_LOCK_FREE
|
|
|
|
// @} group futures
|
|
_GLIBCXX_END_NAMESPACE_VERSION
|
|
} // namespace
|
|
|
|
#endif // C++11
|
|
|
|
#endif // _GLIBCXX_FUTURE
|