107 lines
2.3 KiB
C++
107 lines
2.3 KiB
C++
|
/*
|
||
|
|
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
|
||
|
|
*
|
||
|
|
* Use of this source code is governed by a BSD-style license
|
||
|
|
* that can be found in the LICENSE file in the root of the source
|
||
|
|
* tree. An additional intellectual property rights grant can be found
|
||
|
|
* in the file PATENTS. All contributing project authors may
|
||
|
|
* be found in the AUTHORS file in the root of the source tree.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "rw_lock_generic.h"
|
||
|
|
|
||
|
|
#include "condition_variable_wrapper.h"
|
||
|
|
#include "critical_section_wrapper.h"
|
||
|
|
|
||
|
|
namespace webrtc {
|
||
|
|
RWLockWrapperGeneric::RWLockWrapperGeneric()
|
||
|
|
: _readersActive(0),
|
||
|
|
_writerActive(false),
|
||
|
|
_readersWaiting(0),
|
||
|
|
_writersWaiting(0)
|
||
|
|
{
|
||
|
|
_critSectPtr = CriticalSectionWrapper::CreateCriticalSection();
|
||
|
|
_readCondPtr = ConditionVariableWrapper::CreateConditionVariable();
|
||
|
|
_writeCondPtr = ConditionVariableWrapper::CreateConditionVariable();
|
||
|
|
}
|
||
|
|
|
||
|
|
RWLockWrapperGeneric::~RWLockWrapperGeneric()
|
||
|
|
{
|
||
|
|
delete _writeCondPtr;
|
||
|
|
delete _readCondPtr;
|
||
|
|
delete _critSectPtr;
|
||
|
|
}
|
||
|
|
|
||
|
|
int RWLockWrapperGeneric::Init()
|
||
|
|
{
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void RWLockWrapperGeneric::AcquireLockExclusive()
|
||
|
|
{
|
||
|
|
_critSectPtr->Enter();
|
||
|
|
|
||
|
|
if (_writerActive || _readersActive > 0)
|
||
|
|
{
|
||
|
|
++_writersWaiting;
|
||
|
|
|
||
|
|
while (_writerActive || _readersActive > 0)
|
||
|
|
{
|
||
|
|
_writeCondPtr->SleepCS(*_critSectPtr);
|
||
|
|
}
|
||
|
|
|
||
|
|
--_writersWaiting;
|
||
|
|
}
|
||
|
|
_writerActive = true;
|
||
|
|
_critSectPtr->Leave();
|
||
|
|
}
|
||
|
|
|
||
|
|
void RWLockWrapperGeneric::ReleaseLockExclusive()
|
||
|
|
{
|
||
|
|
_critSectPtr->Enter();
|
||
|
|
|
||
|
|
_writerActive = false;
|
||
|
|
|
||
|
|
if (_writersWaiting > 0)
|
||
|
|
{
|
||
|
|
_writeCondPtr->Wake();
|
||
|
|
|
||
|
|
}else if (_readersWaiting > 0)
|
||
|
|
{
|
||
|
|
_readCondPtr->WakeAll();
|
||
|
|
}
|
||
|
|
_critSectPtr->Leave();
|
||
|
|
}
|
||
|
|
|
||
|
|
void RWLockWrapperGeneric::AcquireLockShared()
|
||
|
|
{
|
||
|
|
_critSectPtr->Enter();
|
||
|
|
|
||
|
|
if (_writerActive || _writersWaiting > 0)
|
||
|
|
{
|
||
|
|
++_readersWaiting;
|
||
|
|
|
||
|
|
while (_writerActive || _writersWaiting > 0)
|
||
|
|
{
|
||
|
|
_readCondPtr->SleepCS(*_critSectPtr);
|
||
|
|
}
|
||
|
|
--_readersWaiting;
|
||
|
|
}
|
||
|
|
++_readersActive;
|
||
|
|
_critSectPtr->Leave();
|
||
|
|
}
|
||
|
|
|
||
|
|
void RWLockWrapperGeneric::ReleaseLockShared()
|
||
|
|
{
|
||
|
|
_critSectPtr->Enter();
|
||
|
|
|
||
|
|
--_readersActive;
|
||
|
|
|
||
|
|
if (_readersActive == 0 && _writersWaiting > 0)
|
||
|
|
{
|
||
|
|
_writeCondPtr->Wake();
|
||
|
|
}
|
||
|
|
_critSectPtr->Leave();
|
||
|
|
}
|
||
|
|
} // namespace webrtc
|