libcruft-util/thread/flag_std.hpp
Danny Robson 01094611eb thread: add minimal thread primitives for win32
This allows us to get around the lack of these types under MinGW
2019-06-22 15:46:34 +10:00

41 lines
1.1 KiB
C++

/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* Copyright 2018 Danny Robson <danny@nerdcruft.net>
*/
#pragma once
#include "mutex.hpp"
#include "condition_variable.hpp"
#include <atomic>
namespace cruft::thread {
/// a fire-once event that users can wait upon. if already fired then
/// waiting will be a noop.
class flag {
public:
flag ();
/// blocks indefinitely until the flag has been set.
void wait (void);
/// wake one thread waiting on the flag.
///
/// it may be possible, through spurious wakeups, that more threads
/// are release than requested. though this should not be typical.
void notify_one (void);
/// wake all threads waiting on the flag
void notify_all (void);
private:
std::atomic<bool> fired;
::cruft::thread::mutex m_mutex;
::cruft::thread::condition_variable m_condition;
};
}