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30
31//////////////////////////////////////////////////////////////////////////
32// Lock.h
33//
34// This file contains the definition and implementation of the Lock class
35// and the TryLock class
36//////////////////////////////////////////////////////////////////////////
37#ifndef _LAD_LOCK_H
38#define _LAD_LOCK_H
39#include "RWLock.h"
40
41#ifndef NULL
42#define NULL 0
43#endif
44
45class Lock
46{
47public:
48	Lock(Semaphore &sem) : _sem(&sem), _rw_lock(NULL)
49	{
50		_sem->acquire();
51	}
52
53	Lock(RWLock &rw_lock, RWLock::RWMode mode = RWLock::READ_ONLY) :
54	_sem(NULL), _rw_lock(&rw_lock)
55	{
56		_rw_lock->acquire(mode);
57	}
58
59	~Lock()
60	{
61		if (_sem) {
62			_sem->release();
63		}
64		if (_rw_lock) {
65			_rw_lock->release();
66		}
67
68	}
69
70private:
71	Semaphore *_sem;
72	RWLock *_rw_lock;
73};
74
75class TryLock
76{
77public:
78	TryLock(Semaphore &sem, bool &is_locked) : _sem(&sem)
79	{
80		_locked = _sem->acquireTry();
81		is_locked = _locked;
82	}
83
84	~TryLock()
85	{
86		if (_locked) {
87			_sem->release();
88		}
89	}
90
91private:
92	bool _locked;
93	Semaphore *_sem;
94};
95
96#endif //_LAD_LOCK_H
97
98