kicad/3d-viewer/openmp_mutex.h

82 lines
2.4 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2016 Mario Luzeiro <mrluzeiro@ua.pt>
* Copyright (C) 1992-2016 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 2
* 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, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
/**
* @file openmp_mutex.h
* @brief a mutex for openmp got from the website:
* http://bisqwit.iki.fi/story/howto/openmp/
* by Joel Yliluoma <bisqwit@iki.fi>
*/
#ifndef _OPENMP_MUTEX_H
#define _OPENMP_MUTEX_H
#ifdef _OPENMP
# include <omp.h>
struct MutexType
{
MutexType() { omp_init_lock( &lock ); }
~MutexType() { omp_destroy_lock( &lock ); }
void Lock() { omp_set_lock( &lock ); }
void Unlock() { omp_unset_lock( &lock ); }
MutexType( const MutexType& ) { omp_init_lock( &lock ); }
MutexType& operator= ( const MutexType& ) { return *this; }
public:
omp_lock_t lock;
};
#else
/// A dummy mutex that doesn't actually exclude anything,
/// but as there is no parallelism either, no worries.
struct MutexType
{
void Lock() {}
void Unlock() {}
};
#endif
/// An exception-safe scoped lock-keeper.
struct ScopedLock
{
explicit ScopedLock( MutexType& m ) : mut( m ), locked( true ) { mut.Lock(); }
~ScopedLock() { Unlock(); }
void Unlock() { if( !locked ) return; locked = false; mut.Unlock(); }
void LockAgain() { if( locked ) return; mut.Lock(); locked = true; }
private:
MutexType& mut;
bool locked;
private: // prevent copying the scoped lock.
void operator=(const ScopedLock&);
ScopedLock(const ScopedLock&);
};
#endif // _OPENMP_MUTEX_H