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//===------------------------- future.cpp ---------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "__config"
#ifndef _LIBCPP_HAS_NO_THREADS
#include "future"
#include "string"
_LIBCPP_BEGIN_NAMESPACE_STD
class _LIBCPP_HIDDEN __future_error_category
: public __do_message
{
public:
virtual const char* name() const _NOEXCEPT;
virtual string message(int ev) const;
};
const char*
__future_error_category::name() const _NOEXCEPT
{
return "future";
}
#if defined(__clang__)
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wswitch"
#elif defined(__GNUC__) || defined(__GNUG__)
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wswitch"
#endif
string
__future_error_category::message(int ev) const
{
switch (static_cast<future_errc>(ev))
{
case future_errc(0): // For backwards compatibility with C++11 (LWG 2056)
case future_errc::broken_promise:
return string("The associated promise has been destructed prior "
"to the associated state becoming ready.");
case future_errc::future_already_retrieved:
return string("The future has already been retrieved from "
"the promise or packaged_task.");
case future_errc::promise_already_satisfied:
return string("The state of the promise has already been set.");
case future_errc::no_state:
return string("Operation not permitted on an object without "
"an associated state.");
}
return string("unspecified future_errc value\n");
}
#if defined(__clang__)
#pragma clang diagnostic pop
#elif defined(__GNUC__) || defined(__GNUG__)
#pragma GCC diagnostic pop
#endif
const error_category&
future_category() _NOEXCEPT
{
static __future_error_category __f;
return __f;
}
future_error::future_error(error_code __ec)
: logic_error(__ec.message()),
__ec_(__ec)
{
}
future_error::~future_error() _NOEXCEPT
{
}
void
__assoc_sub_state::__on_zero_shared() _NOEXCEPT
{
delete this;
}
void
__assoc_sub_state::set_value()
{
unique_lock<mutex> __lk(__mut_);
if (__has_value())
__throw_future_error(future_errc::promise_already_satisfied);
__state_ |= __constructed | ready;
__cv_.notify_all();
}
void
__assoc_sub_state::set_value_at_thread_exit()
{
unique_lock<mutex> __lk(__mut_);
if (__has_value())
__throw_future_error(future_errc::promise_already_satisfied);
__state_ |= __constructed;
__thread_local_data()->__make_ready_at_thread_exit(this);
}
void
__assoc_sub_state::set_exception(exception_ptr __p)
{
unique_lock<mutex> __lk(__mut_);
if (__has_value())
__throw_future_error(future_errc::promise_already_satisfied);
__exception_ = __p;
__state_ |= ready;
__cv_.notify_all();
}
void
__assoc_sub_state::set_exception_at_thread_exit(exception_ptr __p)
{
unique_lock<mutex> __lk(__mut_);
if (__has_value())
__throw_future_error(future_errc::promise_already_satisfied);
__exception_ = __p;
__thread_local_data()->__make_ready_at_thread_exit(this);
}
void
__assoc_sub_state::__make_ready()
{
unique_lock<mutex> __lk(__mut_);
__state_ |= ready;
__cv_.notify_all();
}
void
__assoc_sub_state::copy()
{
unique_lock<mutex> __lk(__mut_);
__sub_wait(__lk);
if (__exception_ != nullptr)
rethrow_exception(__exception_);
}
void
__assoc_sub_state::wait()
{
unique_lock<mutex> __lk(__mut_);
__sub_wait(__lk);
}
void
__assoc_sub_state::__sub_wait(unique_lock<mutex>& __lk)
{
if (!__is_ready())
{
if (__state_ & static_cast<unsigned>(deferred))
{
__state_ &= ~static_cast<unsigned>(deferred);
__lk.unlock();
__execute();
}
else
while (!__is_ready())
__cv_.wait(__lk);
}
}
void
__assoc_sub_state::__execute()
{
__throw_future_error(future_errc::no_state);
}
future<void>::future(__assoc_sub_state* __state)
: __state_(__state)
{
__state_->__attach_future();
}
future<void>::~future()
{
if (__state_)
__state_->__release_shared();
}
void
future<void>::get()
{
unique_ptr<__shared_count, __release_shared_count> __(__state_);
__assoc_sub_state* __s = __state_;
__state_ = nullptr;
__s->copy();
}
promise<void>::promise()
: __state_(new __assoc_sub_state)
{
}
promise<void>::~promise()
{
if (__state_)
{
#ifndef _LIBCPP_NO_EXCEPTIONS
if (!__state_->__has_value() && __state_->use_count() > 1)
__state_->set_exception(make_exception_ptr(
future_error(make_error_code(future_errc::broken_promise))
));
#endif // _LIBCPP_NO_EXCEPTIONS
__state_->__release_shared();
}
}
future<void>
promise<void>::get_future()
{
if (__state_ == nullptr)
__throw_future_error(future_errc::no_state);
return future<void>(__state_);
}
void
promise<void>::set_value()
{
if (__state_ == nullptr)
__throw_future_error(future_errc::no_state);
__state_->set_value();
}
void
promise<void>::set_exception(exception_ptr __p)
{
if (__state_ == nullptr)
__throw_future_error(future_errc::no_state);
__state_->set_exception(__p);
}
void
promise<void>::set_value_at_thread_exit()
{
if (__state_ == nullptr)
__throw_future_error(future_errc::no_state);
__state_->set_value_at_thread_exit();
}
void
promise<void>::set_exception_at_thread_exit(exception_ptr __p)
{
if (__state_ == nullptr)
__throw_future_error(future_errc::no_state);
__state_->set_exception_at_thread_exit(__p);
}
shared_future<void>::~shared_future()
{
if (__state_)
__state_->__release_shared();
}
shared_future<void>&
shared_future<void>::operator=(const shared_future& __rhs)
{
if (__rhs.__state_)
__rhs.__state_->__add_shared();
if (__state_)
__state_->__release_shared();
__state_ = __rhs.__state_;
return *this;
}
_LIBCPP_END_NAMESPACE_STD
#endif // !_LIBCPP_HAS_NO_THREADS