OpenSceneGraph/include/OpenThreads/Block
2012-03-21 17:36:20 +00:00

178 lines
4.3 KiB
C++

/* -*-c++-*- OpenThreads - Copyright (C) 1998-2007 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library 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
* OpenSceneGraph Public License for more details.
*/
#ifndef _OPENTHREADS_BLOCK_
#define _OPENTHREADS_BLOCK_
#include <OpenThreads/Thread>
#include <OpenThreads/Barrier>
#include <OpenThreads/Condition>
#include <OpenThreads/ScopedLock>
namespace OpenThreads {
/** Block is a block that can be used to halt a thread that is waiting another thread to release it.*/
class Block
{
public:
Block():
_released(false) {}
~Block()
{
release();
}
inline bool block()
{
ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if( !_released )
{
return _cond.wait(&_mut)==0;
}
else
{
return true;
}
}
inline bool block(unsigned long timeout)
{
ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if( !_released )
{
return _cond.wait(&_mut, timeout)==0;
}
else
{
return true;
}
}
inline void release()
{
ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if (!_released)
{
_released = true;
_cond.broadcast();
}
}
inline void reset()
{
ScopedLock<OpenThreads::Mutex> mutlock(_mut);
_released = false;
}
inline void set(bool doRelease)
{
if (doRelease!=_released)
{
if (doRelease) release();
else reset();
}
}
protected:
Mutex _mut;
Condition _cond;
bool _released;
private:
Block(const Block&) {}
};
/** BlockCount is a block that can be used to halt a thread that is waiting for a specified number of operations to be completed.*/
class BlockCount
{
public:
BlockCount(unsigned int blockCount):
_blockCount(blockCount),
_currentCount(0) {}
~BlockCount()
{
_blockCount = 0;
release();
}
inline void completed()
{
OpenThreads::ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if (_currentCount>0)
{
--_currentCount;
if (_currentCount==0)
{
// osg::notify(osg::NOTICE)<<"Released"<<std::endl;
_cond.broadcast();
}
}
}
inline void block()
{
OpenThreads::ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if (_currentCount)
_cond.wait(&_mut);
}
inline void reset()
{
OpenThreads::ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if (_currentCount!=_blockCount)
{
if (_blockCount==0) _cond.broadcast();
_currentCount = _blockCount;
}
}
inline void release()
{
OpenThreads::ScopedLock<OpenThreads::Mutex> mutlock(_mut);
if (_currentCount)
{
_currentCount = 0;
_cond.broadcast();
}
}
inline void setBlockCount(unsigned int blockCount) { _blockCount = blockCount; }
inline unsigned int getBlockCount() const { return _blockCount; }
inline unsigned int getCurrentCount() const { return _currentCount; }
protected:
OpenThreads::Mutex _mut;
OpenThreads::Condition _cond;
unsigned int _blockCount;
unsigned int _currentCount;
private:
BlockCount(const BlockCount&) {}
};
}
#endif