xref: /titanic_41/usr/src/cmd/lms/SyncLib/Include/RWLock.h (revision ba7866cd2cbdf574f47d4e38a1301b90744dd677)
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30 
31 #ifndef _RW_LOCK_H_
32 #define _RW_LOCK_H_
33 
34 #include "Semaphore.h"
35 
36 class RWLock
37 {
38 public:
39 	enum RWMode {
40 		READ_ONLY,
41 		READ_WRITE
42 	};
43 
44 	RWLock();
45 	~RWLock() {}
46 
47 	void acquire(const RWMode mode_p = READ_ONLY);
48 	void release();
49 	void switch2RO();
50 
51 private:
52 	Semaphore _readSem;
53 	Semaphore _writeSem;
54 	Semaphore _countSem;
55 	unsigned int _counter;
56 };
57 
58 #endif //_RW_LOCK_H_
59