SyncLib/Include/Lock.h

	Lock.h revision 617e2443dfc17fe44fd44c0675d6aad2ffc9df42
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//////////////////////////////////////////////////////////////////////////
// Lock.h
//
// This file contains the definition and implementation of the Lock class
// and the TryLock class
//////////////////////////////////////////////////////////////////////////
#ifndef _LAD_LOCK_H
#define _LAD_LOCK_H
#include "RWLock.h"

#ifndef NULL
#define NULL 0
#endif

class Lock
{
public:
    Lock(Semaphore &sem) : _sem(&sem), _rw_lock(NULL)
    {
        _sem->acquire();
    }

    Lock(RWLock &rw_lock, RWLock::RWMode mode = RWLock::READ_ONLY) :
    _sem(NULL), _rw_lock(&rw_lock)
    {
        _rw_lock->acquire(mode);
    }

    ~Lock()
    {
        if (_sem) {
            _sem->release();
        }
        if (_rw_lock) {
            _rw_lock->release();
        }

    }

private:
    Semaphore *_sem;
    RWLock *_rw_lock;
};

class TryLock
{
public:
    TryLock(Semaphore &sem, bool &is_locked) : _sem(&sem)
    {
        _locked = _sem->acquireTry();
        is_locked = _locked;
    }

    ~TryLock()
    {
        if (_locked) {
            _sem->release();
        }
    }

private:
    bool _locked;
    Semaphore *_sem;
};

#endif //_LAD_LOCK_H