29 #ifndef _GLIBCXX_FUTURE
30 #define _GLIBCXX_FUTURE 1
32 #pragma GCC system_header
34 #if __cplusplus < 201103L
46 #include <bits/shared_ptr.h>
49 #include <bits/uses_allocator.h>
52 namespace std _GLIBCXX_VISIBILITY(default)
54 _GLIBCXX_BEGIN_NAMESPACE_VERSION
67 future_already_retrieved = 1,
68 promise_already_satisfied,
87 inline error_condition
106 what()
const noexcept;
109 code()
const noexcept {
return _M_code; }
114 :
logic_error(
"std::future_error: " + __ec.message()), _M_code(__ec)
117 friend void __throw_future_error(
int);
123 template<
typename _Res>
126 template<
typename _Res>
129 template<
typename _Signature>
132 template<
typename _Res>
144 return static_cast<launch>(
145 static_cast<int>(__x) & static_cast<int>(__y));
150 return static_cast<launch>(
151 static_cast<int>(__x) | static_cast<int>(__y));
156 return static_cast<launch>(
157 static_cast<int>(__x) ^ static_cast<int>(__y));
161 {
return static_cast<launch>(~static_cast<
int>(__x)); }
164 {
return __x = __x & __y; }
167 {
return __x = __x | __y; }
170 {
return __x = __x ^ __y; }
182 template<
typename _Fn,
typename... _Args>
183 using __async_result_of =
typename __invoke_result<
184 typename decay<_Fn>::type,
typename decay<_Args>::type...>::type;
186 template<
typename _Fn,
typename... _Args>
187 future<__async_result_of<_Fn, _Args...>>
188 async(
launch __policy, _Fn&& __fn, _Args&&... __args);
190 template<
typename _Fn,
typename... _Args>
191 future<__async_result_of<_Fn, _Args...>>
192 async(_Fn&& __fn, _Args&&... __args);
194 #if defined(_GLIBCXX_HAS_GTHREADS)
202 exception_ptr _M_error;
208 virtual void _M_destroy() = 0;
212 void operator()(
_Result_base* __fr)
const { __fr->_M_destroy(); }
221 template<
typename _Res>
225 template<
typename _Res>
229 __gnu_cxx::__aligned_buffer<_Res> _M_storage;
233 typedef _Res result_type;
235 _Result() noexcept : _M_initialized() { }
245 _M_value() noexcept {
return *_M_storage._M_ptr(); }
248 _M_set(
const _Res& __res)
250 ::new (_M_storage._M_addr()) _Res(__res);
251 _M_initialized =
true;
257 ::new (_M_storage._M_addr()) _Res(
std::move(__res));
258 _M_initialized =
true;
262 void _M_destroy() {
delete this; }
266 template<
typename _Res,
typename _Alloc>
269 using __allocator_type = __alloc_rebind<_Alloc, _Result_alloc>;
278 __allocator_type __a(*
this);
285 template<
typename _Res,
typename _Allocator>
287 _S_allocate_result(
const _Allocator& __a)
290 typename __result_type::__allocator_type __a2(__a);
292 __result_type* __p = ::new((
void*)__guard.get()) __result_type{__a};
294 return _Ptr<__result_type>(__p);
298 template<
typename _Res,
typename _Tp>
299 static _Ptr<_Result<_Res>>
302 return _Ptr<_Result<_Res>>(
new _Result<_Res>);
310 typedef _Ptr<_Result_base> _Ptr_type;
312 enum _Status :
unsigned {
318 __atomic_futex_unsigned<> _M_status;
319 atomic_flag _M_retrieved = ATOMIC_FLAG_INIT;
323 _State_baseV2() noexcept : _M_result(), _M_status(_Status::__not_ready)
325 _State_baseV2(
const _State_baseV2&) =
delete;
326 _State_baseV2&
operator=(
const _State_baseV2&) =
delete;
327 virtual ~_State_baseV2() =
default;
336 _M_status._M_load_when_equal(_Status::__ready, memory_order_acquire);
340 template<
typename _Rep,
typename _Period>
342 wait_for(
const chrono::duration<_Rep, _Period>& __rel)
346 if (_M_status._M_load(memory_order_acquire) == _Status::__ready)
347 return future_status::ready;
349 if (_M_is_deferred_future())
350 return future_status::deferred;
353 if (__rel > __rel.zero()
354 && _M_status._M_load_when_equal_for(_Status::__ready,
355 memory_order_acquire,
369 return future_status::ready;
371 return future_status::timeout;
374 template<
typename _Clock,
typename _Duration>
376 wait_until(
const chrono::time_point<_Clock, _Duration>& __abs)
378 #if __cplusplus > 201703L
379 static_assert(chrono::is_clock_v<_Clock>);
383 if (_M_status._M_load(memory_order_acquire) == _Status::__ready)
384 return future_status::ready;
386 if (_M_is_deferred_future())
387 return future_status::deferred;
389 if (_M_status._M_load_when_equal_until(_Status::__ready,
390 memory_order_acquire,
398 return future_status::ready;
400 return future_status::timeout;
406 _M_set_result(
function<_Ptr_type()> __res,
bool __ignore_failure =
false)
408 bool __did_set =
false;
411 call_once(_M_once, &_State_baseV2::_M_do_set,
this,
415 _M_status._M_store_notify_all(_Status::__ready,
416 memory_order_release);
417 else if (!__ignore_failure)
418 __throw_future_error(
int(future_errc::promise_already_satisfied));
425 _M_set_delayed_result(
function<_Ptr_type()> __res,
426 weak_ptr<_State_baseV2> __self)
428 bool __did_set =
false;
429 unique_ptr<_Make_ready> __mr{
new _Make_ready};
432 call_once(_M_once, &_State_baseV2::_M_do_set,
this,
435 __throw_future_error(
int(future_errc::promise_already_satisfied));
436 __mr->_M_shared_state =
std::move(__self);
443 _M_break_promise(_Ptr_type __res)
445 if (static_cast<bool>(__res))
453 _M_result.swap(__res);
455 _M_status._M_store_notify_all(_Status::__ready,
456 memory_order_release);
462 _M_set_retrieved_flag()
464 if (_M_retrieved.test_and_set())
465 __throw_future_error(
int(future_errc::future_already_retrieved));
468 template<
typename _Res,
typename _Arg>
472 template<
typename _Res,
typename _Arg>
473 struct _Setter<_Res, _Arg&>
477 static_assert(is_same<_Res, _Arg&>::value
478 || is_same<const _Res, _Arg>::value,
479 "Invalid specialisation");
482 typename promise<_Res>::_Ptr_type operator()()
const
484 _M_promise->_M_storage->_M_set(*_M_arg);
485 return std::move(_M_promise->_M_storage);
487 promise<_Res>* _M_promise;
492 template<
typename _Res>
493 struct _Setter<_Res, _Res&&>
496 typename promise<_Res>::_Ptr_type operator()()
const
498 _M_promise->_M_storage->_M_set(
std::move(*_M_arg));
499 return std::move(_M_promise->_M_storage);
501 promise<_Res>* _M_promise;
506 template<
typename _Res>
507 struct _Setter<_Res, void>
509 static_assert(is_void<_Res>::value,
"Only used for promise<void>");
511 typename promise<_Res>::_Ptr_type operator()()
const
512 {
return std::move(_M_promise->_M_storage); }
514 promise<_Res>* _M_promise;
517 struct __exception_ptr_tag { };
520 template<
typename _Res>
521 struct _Setter<_Res, __exception_ptr_tag>
524 typename promise<_Res>::_Ptr_type operator()()
const
526 _M_promise->_M_storage->_M_error = *_M_ex;
527 return std::move(_M_promise->_M_storage);
530 promise<_Res>* _M_promise;
531 exception_ptr* _M_ex;
534 template<
typename _Res,
typename _Arg>
535 __attribute__((__always_inline__))
536 static _Setter<_Res, _Arg&&>
537 __setter(promise<_Res>* __prom, _Arg&& __arg) noexcept
542 template<
typename _Res>
543 __attribute__((__always_inline__))
544 static _Setter<_Res, __exception_ptr_tag>
545 __setter(exception_ptr& __ex, promise<_Res>* __prom) noexcept
547 return _Setter<_Res, __exception_ptr_tag>{ __prom, &__ex };
550 template<
typename _Res>
551 __attribute__((__always_inline__))
552 static _Setter<_Res,
void>
553 __setter(promise<_Res>* __prom) noexcept
555 return _Setter<_Res, void>{ __prom };
558 template<
typename _Tp>
560 _S_check(
const shared_ptr<_Tp>& __p)
562 if (!static_cast<bool>(__p))
563 __throw_future_error((
int)future_errc::no_state);
569 _M_do_set(
function<_Ptr_type()>* __f,
bool* __did_set)
571 _Ptr_type __res = (*__f)();
576 _M_result.swap(__res);
580 virtual void _M_complete_async() { }
583 virtual bool _M_is_deferred_future()
const {
return false; }
585 struct _Make_ready final : __at_thread_exit_elt
587 weak_ptr<_State_baseV2> _M_shared_state;
588 static void _S_run(
void*);
593 #ifdef _GLIBCXX_ASYNC_ABI_COMPAT
595 class _Async_state_common;
597 using _State_base = _State_baseV2;
598 class _Async_state_commonV2;
601 template<
typename _BoundFn,
602 typename _Res = decltype(std::declval<_BoundFn&>()())>
603 class _Deferred_state;
605 template<
typename _BoundFn,
606 typename _Res = decltype(std::declval<_BoundFn&>()())>
607 class _Async_state_impl;
609 template<
typename _Signature>
610 class _Task_state_base;
612 template<
typename _Fn,
typename _Alloc,
typename _Signature>
615 template<
typename _Res_ptr,
typename _Fn,
616 typename _Res =
typename _Res_ptr::element_type::result_type>
619 template<
typename _Res_ptr,
typename _BoundFn>
620 static _Task_setter<_Res_ptr, _BoundFn>
621 _S_task_setter(_Res_ptr& __ptr, _BoundFn& __call)
628 template<
typename _Res>
631 typedef _Res& result_type;
633 _Result() noexcept : _M_value_ptr() { }
636 _M_set(_Res& __res) noexcept
639 _Res& _M_get() noexcept {
return *_M_value_ptr; }
644 void _M_destroy() {
delete this; }
651 typedef void result_type;
654 void _M_destroy() {
delete this; }
657 #ifndef _GLIBCXX_ASYNC_ABI_COMPAT
660 template<
typename _Res,
typename _Arg>
666 template<
typename _Res_ptr,
typename _Fn,
typename _Res>
672 template<
typename _Res>
688 valid()
const noexcept {
return static_cast<bool>(_M_state); }
693 _State_base::_S_check(_M_state);
697 template<
typename _Rep,
typename _Period>
701 _State_base::_S_check(_M_state);
702 return _M_state->wait_for(__rel);
705 template<
typename _Clock,
typename _Duration>
709 _State_base::_S_check(_M_state);
710 return _M_state->wait_until(__abs);
718 _State_base::_S_check(_M_state);
720 if (!(__res._M_error ==
nullptr))
727 _M_state.swap(__that._M_state);
732 __basic_future(
const __state_type& __state) : _M_state(__state)
734 _State_base::_S_check(_M_state);
735 _M_state->_M_set_retrieved_flag();
740 __basic_future(
const shared_future<_Res>&) noexcept;
744 __basic_future(shared_future<_Res>&&) noexcept;
748 __basic_future(future<_Res>&&) noexcept;
750 constexpr __basic_future() noexcept : _M_state() { }
754 explicit _Reset(__basic_future& __fut) noexcept : _M_fut(__fut) { }
755 ~_Reset() { _M_fut._M_state.reset(); }
756 __basic_future& _M_fut;
762 template<
typename _Res>
763 class future :
public __basic_future<_Res>
767 static_assert(!is_array<_Res>{},
"result type must not be an array");
768 static_assert(!is_function<_Res>{},
"result type must not be a function");
769 static_assert(is_destructible<_Res>{},
770 "result type must be destructible");
772 friend class promise<_Res>;
773 template<
typename>
friend class packaged_task;
774 template<
typename _Fn,
typename... _Args>
775 friend future<__async_result_of<_Fn, _Args...>>
778 typedef __basic_future<_Res> _Base_type;
779 typedef typename _Base_type::__state_type __state_type;
782 future(
const __state_type& __state) : _Base_type(__state) { }
785 constexpr future() noexcept : _Base_type() { }
804 typename _Base_type::_Reset __reset(*
this);
812 template<typename _Res>
816 template<
typename>
friend class packaged_task;
817 template<
typename _Fn,
typename... _Args>
818 friend future<__async_result_of<_Fn, _Args...>>
825 future(
const __state_type& __state) : _Base_type(__state) { }
828 constexpr
future() noexcept : _Base_type() { }
847 typename _Base_type::_Reset __reset(*
this);
859 template<
typename>
friend class packaged_task;
860 template<
typename _Fn,
typename... _Args>
861 friend future<__async_result_of<_Fn, _Args...>>
868 future(
const __state_type& __state) : _Base_type(__state) { }
871 constexpr
future() noexcept : _Base_type() { }
890 typename _Base_type::_Reset __reset(*
this);
899 template<typename _Res>
904 static_assert(!
is_array<_Res>{},
"result type must not be an array");
905 static_assert(!is_function<_Res>{},
"result type must not be a function");
906 static_assert(is_destructible<_Res>{},
907 "result type must be destructible");
909 typedef __basic_future<_Res> _Base_type;
912 constexpr shared_future() noexcept : _Base_type() { }
919 : _Base_type(std::
move(__uf))
924 : _Base_type(std::
move(__sf))
933 shared_future&
operator=(shared_future&& __sf) noexcept
935 shared_future(
std::move(__sf))._M_swap(*
this);
945 template<
typename _Res>
958 : _Base_type(std::
move(__uf))
963 : _Base_type(std::
move(__sf))
972 shared_future&
operator=(shared_future&& __sf) noexcept
974 shared_future(
std::move(__sf))._M_swap(*
this);
997 : _Base_type(std::
move(__uf))
1002 : _Base_type(std::
move(__sf))
1011 shared_future&
operator=(shared_future&& __sf) noexcept
1013 shared_future(
std::move(__sf))._M_swap(*
this);
1023 template<
typename _Res>
1024 inline __basic_future<_Res>::
1025 __basic_future(
const shared_future<_Res>& __sf) noexcept
1026 : _M_state(__sf._M_state)
1029 template<
typename _Res>
1030 inline __basic_future<_Res>::
1031 __basic_future(shared_future<_Res>&& __sf) noexcept
1032 : _M_state(std::
move(__sf._M_state))
1035 template<
typename _Res>
1036 inline __basic_future<_Res>::
1037 __basic_future(future<_Res>&& __uf) noexcept
1038 : _M_state(std::
move(__uf._M_state))
1043 template<
typename _Res>
1044 inline shared_future<_Res>
1045 future<_Res>::share() noexcept
1046 {
return shared_future<_Res>(
std::move(*
this)); }
1048 template<
typename _Res>
1049 inline shared_future<_Res&>
1050 future<_Res&>::share() noexcept
1051 {
return shared_future<_Res&>(
std::move(*
this)); }
1053 inline shared_future<void>
1054 future<void>::share() noexcept
1055 {
return shared_future<void>(
std::move(*
this)); }
1058 template<
typename _Res>
1063 static_assert(!is_array<_Res>{},
"result type must not be an array");
1064 static_assert(!is_function<_Res>{},
"result type must not be a function");
1065 static_assert(is_destructible<_Res>{},
1066 "result type must be destructible");
1068 typedef __future_base::_State_base _State;
1069 typedef __future_base::_Result<_Res> _Res_type;
1070 typedef __future_base::_Ptr<_Res_type> _Ptr_type;
1071 template<
typename,
typename>
friend struct _State::_Setter;
1074 shared_ptr<_State> _M_future;
1075 _Ptr_type _M_storage;
1079 : _M_future(std::make_shared<_State>()),
1080 _M_storage(new _Res_type())
1083 promise(promise&& __rhs) noexcept
1084 : _M_future(std::
move(__rhs._M_future)),
1085 _M_storage(std::
move(__rhs._M_storage))
1088 template<
typename _Allocator>
1089 promise(allocator_arg_t,
const _Allocator& __a)
1090 : _M_future(std::allocate_shared<_State>(__a)),
1091 _M_storage(__future_base::_S_allocate_result<_Res>(__a))
1094 template<
typename _Allocator>
1095 promise(allocator_arg_t,
const _Allocator&, promise&& __rhs)
1096 : _M_future(std::
move(__rhs._M_future)),
1097 _M_storage(std::
move(__rhs._M_storage))
1100 promise(
const promise&) =
delete;
1104 if (static_cast<bool>(_M_future) && !_M_future.unique())
1105 _M_future->_M_break_promise(
std::move(_M_storage));
1116 promise&
operator=(
const promise&) =
delete;
1119 swap(promise& __rhs) noexcept
1121 _M_future.swap(__rhs._M_future);
1122 _M_storage.swap(__rhs._M_storage);
1128 {
return future<_Res>(_M_future); }
1132 set_value(
const _Res& __r)
1133 { _M_state()._M_set_result(_State::__setter(
this, __r)); }
1136 set_value(_Res&& __r)
1137 { _M_state()._M_set_result(_State::__setter(
this,
std::move(__r))); }
1140 set_exception(exception_ptr __p)
1141 { _M_state()._M_set_result(_State::__setter(__p,
this)); }
1144 set_value_at_thread_exit(
const _Res& __r)
1146 _M_state()._M_set_delayed_result(_State::__setter(
this, __r),
1151 set_value_at_thread_exit(_Res&& __r)
1153 _M_state()._M_set_delayed_result(
1154 _State::__setter(
this,
std::move(__r)), _M_future);
1158 set_exception_at_thread_exit(exception_ptr __p)
1160 _M_state()._M_set_delayed_result(_State::__setter(__p,
this),
1168 __future_base::_State_base::_S_check(_M_future);
1173 template<
typename _Res>
1175 swap(promise<_Res>& __x, promise<_Res>& __y) noexcept
1178 template<
typename _Res,
typename _Alloc>
1179 struct uses_allocator<promise<_Res>, _Alloc>
1184 template<
typename _Res>
1187 typedef __future_base::_State_base _State;
1190 template<
typename,
typename>
friend struct _State::_Setter;
1194 _Ptr_type _M_storage;
1198 : _M_future(std::make_shared<_State>()),
1199 _M_storage(
new _Res_type())
1203 : _M_future(
std::move(__rhs._M_future)),
1207 template<
typename _Allocator>
1209 : _M_future(std::allocate_shared<_State>(__a)),
1210 _M_storage(__future_base::_S_allocate_result<_Res&>(__a))
1213 template<
typename _Allocator>
1215 : _M_future(
std::move(__rhs._M_future)),
1223 if (static_cast<bool>(_M_future) && !_M_future.unique())
1224 _M_future->_M_break_promise(
std::move(_M_storage));
1240 _M_future.swap(__rhs._M_future);
1241 _M_storage.
swap(__rhs._M_storage);
1251 set_value(_Res& __r)
1252 { _M_state()._M_set_result(_State::__setter(
this, __r)); }
1255 set_exception(exception_ptr __p)
1256 { _M_state()._M_set_result(_State::__setter(__p,
this)); }
1259 set_value_at_thread_exit(_Res& __r)
1261 _M_state()._M_set_delayed_result(_State::__setter(
this, __r),
1266 set_exception_at_thread_exit(exception_ptr __p)
1268 _M_state()._M_set_delayed_result(_State::__setter(__p,
this),
1276 __future_base::_State_base::_S_check(_M_future);
1285 typedef __future_base::_State_base _State;
1288 template<
typename,
typename>
friend struct _State::_Setter;
1296 : _M_future(std::make_shared<_State>()),
1301 : _M_future(
std::move(__rhs._M_future)),
1305 template<
typename _Allocator>
1307 : _M_future(std::allocate_shared<_State>(__a)),
1308 _M_storage(__future_base::_S_allocate_result<void>(__a))
1313 template<
typename _Allocator>
1315 : _M_future(
std::move(__rhs._M_future)),
1323 if (static_cast<bool>(_M_future) && !_M_future.unique())
1324 _M_future->_M_break_promise(
std::move(_M_storage));
1340 _M_future.swap(__rhs._M_future);
1341 _M_storage.swap(__rhs._M_storage);
1352 { _M_state()._M_set_result(_State::__setter(
this)); }
1355 set_exception(exception_ptr __p)
1356 { _M_state()._M_set_result(_State::__setter(__p,
this)); }
1359 set_value_at_thread_exit()
1360 { _M_state()._M_set_delayed_result(_State::__setter(
this), _M_future); }
1363 set_exception_at_thread_exit(exception_ptr __p)
1365 _M_state()._M_set_delayed_result(_State::__setter(__p,
this),
1373 __future_base::_State_base::_S_check(_M_future);
1378 template<
typename _Ptr_type,
typename _Fn,
typename _Res>
1379 struct __future_base::_Task_setter
1382 _Ptr_type operator()()
const
1386 (*_M_result)->_M_set((*_M_fn)());
1390 __throw_exception_again;
1398 _Ptr_type* _M_result;
1402 template<
typename _Ptr_type,
typename _Fn>
1403 struct __future_base::_Task_setter<_Ptr_type, _Fn, void>
1405 _Ptr_type operator()()
const
1413 __throw_exception_again;
1421 _Ptr_type* _M_result;
1426 template<
typename _Res,
typename... _Args>
1427 struct __future_base::_Task_state_base<_Res(_Args...)>
1428 : __future_base::_State_base
1430 typedef _Res _Res_type;
1432 template<
typename _Alloc>
1433 _Task_state_base(
const _Alloc& __a)
1434 : _M_result(_S_allocate_result<_Res>(__a))
1439 _M_run(_Args&&... __args) = 0;
1443 _M_run_delayed(_Args&&... __args, weak_ptr<_State_base>) = 0;
1445 virtual shared_ptr<_Task_state_base>
1448 typedef __future_base::_Ptr<_Result<_Res>> _Ptr_type;
1449 _Ptr_type _M_result;
1453 template<
typename _Fn,
typename _Alloc,
typename _Res,
typename... _Args>
1454 struct __future_base::_Task_state<_Fn, _Alloc, _Res(_Args...)> final
1455 : __future_base::_Task_state_base<_Res(_Args...)>
1457 template<
typename _Fn2>
1458 _Task_state(_Fn2&& __fn,
const _Alloc& __a)
1459 : _Task_state_base<_Res(_Args...)>(__a),
1460 _M_impl(std::
forward<_Fn2>(__fn), __a)
1465 _M_run(_Args&&... __args)
1467 auto __boundfn = [&] () -> _Res {
1468 return std::__invoke_r<_Res>(_M_impl._M_fn,
1469 std::forward<_Args>(__args)...);
1471 this->_M_set_result(_S_task_setter(this->_M_result, __boundfn));
1475 _M_run_delayed(_Args&&... __args, weak_ptr<_State_base> __self)
1477 auto __boundfn = [&] () -> _Res {
1478 return std::__invoke_r<_Res>(_M_impl._M_fn,
1479 std::forward<_Args>(__args)...);
1481 this->_M_set_delayed_result(_S_task_setter(this->_M_result, __boundfn),
1485 virtual shared_ptr<_Task_state_base<_Res(_Args...)>>
1488 struct _Impl : _Alloc
1490 template<
typename _Fn2>
1491 _Impl(_Fn2&& __fn,
const _Alloc& __a)
1492 : _Alloc(__a), _M_fn(std::
forward<_Fn2>(__fn)) { }
1497 template<
typename _Signature,
typename _Fn,
1499 static shared_ptr<__future_base::_Task_state_base<_Signature>>
1500 __create_task_state(_Fn&& __fn,
const _Alloc& __a = _Alloc())
1502 typedef typename decay<_Fn>::type _Fn2;
1503 typedef __future_base::_Task_state<_Fn2, _Alloc, _Signature> _State;
1504 return std::allocate_shared<_State>(__a, std::forward<_Fn>(__fn), __a);
1507 template<
typename _Fn,
typename _Alloc,
typename _Res,
typename... _Args>
1508 shared_ptr<__future_base::_Task_state_base<_Res(_Args...)>>
1509 __future_base::_Task_state<_Fn, _Alloc, _Res(_Args...)>::_M_reset()
1511 return __create_task_state<_Res(_Args...)>(
std::move(_M_impl._M_fn),
1512 static_cast<_Alloc&
>(_M_impl));
1516 template<
typename _Res,
typename... _ArgTypes>
1517 class packaged_task<_Res(_ArgTypes...)>
1519 typedef __future_base::_Task_state_base<_Res(_ArgTypes...)> _State_type;
1524 template<
typename _Fn,
typename _Fn2 = __remove_cvref_t<_Fn>>
1530 packaged_task() noexcept { }
1532 template<
typename _Fn,
typename = __not_same<_Fn>>
1534 packaged_task(_Fn&& __fn)
1536 __create_task_state<_Res(_ArgTypes...)>(std::forward<_Fn>(__fn)))
1539 #if __cplusplus < 201703L
1544 template<
typename _Fn,
typename _Alloc,
typename = __not_same<_Fn>>
1546 : _M_state(__create_task_state<_Res(_ArgTypes...)>(
1547 std::forward<_Fn>(__fn), __a))
1552 template<
typename _Allocator>
1556 template<
typename _Allocator>
1558 const packaged_task&) =
delete;
1560 template<
typename _Allocator>
1562 packaged_task&& __other) noexcept
1563 { this->swap(__other); }
1568 if (static_cast<bool>(_M_state) && !_M_state.unique())
1569 _M_state->_M_break_promise(
std::move(_M_state->_M_result));
1573 packaged_task(
const packaged_task&) =
delete;
1574 packaged_task&
operator=(
const packaged_task&) =
delete;
1577 packaged_task(packaged_task&& __other) noexcept
1578 { this->swap(__other); }
1580 packaged_task&
operator=(packaged_task&& __other) noexcept
1582 packaged_task(
std::move(__other)).swap(*
this);
1587 swap(packaged_task& __other) noexcept
1588 { _M_state.swap(__other._M_state); }
1591 valid()
const noexcept
1592 {
return static_cast<bool>(_M_state); }
1601 operator()(_ArgTypes... __args)
1603 __future_base::_State_base::_S_check(_M_state);
1604 _M_state->_M_run(std::forward<_ArgTypes>(__args)...);
1608 make_ready_at_thread_exit(_ArgTypes... __args)
1610 __future_base::_State_base::_S_check(_M_state);
1611 _M_state->_M_run_delayed(std::forward<_ArgTypes>(__args)..., _M_state);
1617 __future_base::_State_base::_S_check(_M_state);
1618 packaged_task __tmp;
1619 __tmp._M_state = _M_state;
1620 _M_state = _M_state->_M_reset();
1625 template<
typename _Res,
typename... _ArgTypes>
1627 swap(packaged_task<_Res(_ArgTypes...)>& __x,
1628 packaged_task<_Res(_ArgTypes...)>& __y) noexcept
1631 #if __cplusplus < 201703L
1634 template<
typename _Res,
typename _Alloc>
1635 struct uses_allocator<packaged_task<_Res>, _Alloc>
1641 template<
typename _BoundFn,
typename _Res>
1642 class __future_base::_Deferred_state final
1643 :
public __future_base::_State_base
1646 template<
typename... _Args>
1648 _Deferred_state(_Args&&... __args)
1649 : _M_result(new _Result<_Res>()),
1650 _M_fn{{std::forward<_Args>(__args)...}}
1654 typedef __future_base::_Ptr<_Result<_Res>> _Ptr_type;
1655 _Ptr_type _M_result;
1668 _M_set_result(_S_task_setter(_M_result, _M_fn),
true);
1673 virtual bool _M_is_deferred_future()
const {
return true; }
1677 class __future_base::_Async_state_commonV2
1678 :
public __future_base::_State_base
1681 ~_Async_state_commonV2() =
default;
1698 virtual void _M_complete_async() { _M_join(); }
1700 void _M_join() {
std::call_once(_M_once, &thread::join, &_M_thread); }
1708 template<
typename _BoundFn,
typename _Res>
1709 class __future_base::_Async_state_impl final
1710 :
public __future_base::_Async_state_commonV2
1713 template<
typename... _Args>
1715 _Async_state_impl(_Args&&... __args)
1716 : _M_result(new _Result<_Res>()),
1717 _M_fn{{std::forward<_Args>(__args)...}}
1719 _M_thread =
std::thread{&_Async_state_impl::_M_run,
this};
1725 ~_Async_state_impl()
1727 if (_M_thread.joinable())
1737 _M_set_result(_S_task_setter(_M_result, _M_fn));
1742 if (static_cast<bool>(_M_result))
1743 this->_M_break_promise(
std::move(_M_result));
1744 __throw_exception_again;
1748 typedef __future_base::_Ptr<_Result<_Res>> _Ptr_type;
1749 _Ptr_type _M_result;
1755 template<
typename _Fn,
typename... _Args>
1756 _GLIBCXX_NODISCARD future<__async_result_of<_Fn, _Args...>>
1759 using _Wr = std::thread::_Call_wrapper<_Fn, _Args...>;
1760 using _As = __future_base::_Async_state_impl<_Wr>;
1761 using _Ds = __future_base::_Deferred_state<_Wr>;
1764 if ((__policy & launch::async) == launch::async)
1768 __state = std::make_shared<_As>(std::forward<_Fn>(__fn),
1769 std::forward<_Args>(__args)...);
1771 #if __cpp_exceptions
1774 if (__e.code() != errc::resource_unavailable_try_again
1775 || (__policy & launch::deferred) != launch::deferred)
1782 __state = std::make_shared<_Ds>(std::forward<_Fn>(__fn),
1783 std::forward<_Args>(__args)...);
1789 template<
typename _Fn,
typename... _Args>
1790 _GLIBCXX_NODISCARD
inline future<__async_result_of<_Fn, _Args...>>
1793 return std::async(launch::async|launch::deferred,
1794 std::forward<_Fn>(__fn),
1795 std::forward<_Args>(__args)...);
1798 #endif // _GLIBCXX_ASYNC_ABI_COMPAT
1799 #endif // _GLIBCXX_HAS_GTHREADS
1802 _GLIBCXX_END_NAMESPACE_VERSION
1807 #endif // _GLIBCXX_FUTURE
One of two subclasses of exception.
shared_future(const shared_future &__sf)
Copy constructor.
Partial specialization for future<R&>
Thrown as part of forced unwinding.A magic placeholder class that can be caught by reference to recog...
future(future &&__uf) noexcept
Move constructor.
exception_ptr current_exception() noexcept
bitset< _Nb > operator&(const bitset< _Nb > &__x, const bitset< _Nb > &__y) noexcept
Global bitwise operations on bitsets.
constexpr std::remove_reference< _Tp >::type && move(_Tp &&__t) noexcept
Convert a value to an rvalue.
Explicit specialization for shared_future<void>
future< __async_result_of< _Fn, _Args...> > async(launch __policy, _Fn &&__fn, _Args &&...__args)
async
future(future &&__uf) noexcept
Move constructor.
__result_type _M_get_result() const
Wait for the state to be ready and rethrow any stored exception.
const error_category & future_category() noexcept
Points to a statically-allocated object derived from error_category.
exception_ptr make_exception_ptr(_Ex) noexcept
Obtain an exception_ptr pointing to a copy of the supplied object.
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
logic_error(const string &__arg) _GLIBCXX_TXN_SAFE
error_condition make_error_condition(future_errc __errc) noexcept
Overload for make_error_condition.
20.7.1.2 unique_ptr for single objects.
Primary template for promise.
An exception type that includes an error_code value.
Partial specialization for shared_future<R&>
void reset(element_type *__p=0)
Forcibly deletes the managed object.
A result object that has storage for an object of type _Res.
shared_future(future< void > &&__uf) noexcept
Construct from a future rvalue.
shared_future(shared_future &&__sf) noexcept
Construct from a shared_future rvalue.
A result object that uses an allocator.
Primary template for future.
__allocated_ptr< _Alloc > __allocate_guarded(_Alloc &__a)
Allocate space for a single object using __a.
Exception type thrown by futures.
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
constexpr _Tp * addressof(_Tp &__r) noexcept
Returns the actual address of the object or function referenced by r, even in the presence of an over...
virtual const char * what() const noexcept
void swap(unique_ptr &__u) noexcept
Exchange the pointer and deleter with another object.
void rethrow_exception(exception_ptr)
Throw the object pointed to by the exception_ptr.
The standard allocator, as per C++03 [20.4.1].
shared_future(const shared_future &__sf)
Copy constructor.
future_errc
Error code for futures.
Primary template for shared_future.
Common implementation for future and shared_future.
shared_future(future< _Res & > &&__uf) noexcept
Construct from a future rvalue.
Explicit specialization for future<void>
Define a member typedef type only if a boolean constant is true.
future< __async_result_of< _Fn, _Args...> > async(_Fn &&__fn, _Args &&...__args)
async, potential overload
Explicit specialization for void.
launch
Launch code for futures.
shared_future(const shared_future &__sf) noexcept
Copy constructor.
shared_future(shared_future &&__sf) noexcept
Construct from a shared_future rvalue.
shared_future(shared_future &&__sf) noexcept
Construct from a shared_future rvalue.
bitset< _Nb > operator^(const bitset< _Nb > &__x, const bitset< _Nb > &__y) noexcept
Global bitwise operations on bitsets.
Base class and enclosing scope.
bitset< _Nb > operator|(const bitset< _Nb > &__x, const bitset< _Nb > &__y) noexcept
Global bitwise operations on bitsets.
future_status
Status code for futures.
constexpr _Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
void call_once(once_flag &__once, _Callable &&__f, _Args &&...__args)
Invoke a callable and synchronize with other calls using the same flag.
shared_future(future< _Res > &&__uf) noexcept
Construct from a future rvalue.
future(future &&__uf) noexcept
Move constructor.
auto_ptr & operator=(auto_ptr &__a)
auto_ptr assignment operator.
Non-standard RAII type for managing pointers obtained from allocators.
Partial specialization for reference types.