kicad/include/core/spinlock.h

61 lines
1.4 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2021 KiCad Developers, see AUTHORS.txt for contributors.
*
* This program 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 of the License, or (at your
* option) any later version.
*
* This program 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.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __KICAD_SPINLOCK_H
#define __KICAD_SPINLOCK_H
#include <atomic>
/**
* A trivial spinlock implementation with no optimization. Don't use if congestion is expected!
*/
class KISPINLOCK
{
public:
KISPINLOCK() :
m_lock( false )
{}
void lock()
{
while( m_lock.exchange( true, std::memory_order_acquire ) );
}
bool try_lock()
{
return !m_lock.exchange( true, std::memory_order_acquire );
}
void unlock()
{
m_lock.store( false, std::memory_order_release );
}
bool test()
{
return m_lock.load( std::memory_order_acquire );
}
private:
std::atomic<bool> m_lock;
};
#endif