xref: /onnv-gate/usr/src/cmd/lms/SyncLib/Include/RWLock.h (revision 9203:3ebffd0a1b10)

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#ifndef _RW_LOCK_H_
#define _RW_LOCK_H_

#include "Semaphore.h"

class RWLock
{
public:
	enum RWMode {
		READ_ONLY,
		READ_WRITE
	};

	RWLock();
	~RWLock() {}

	void acquire(const RWMode mode_p = READ_ONLY);
	void release();
	void switch2RO();

private:
	Semaphore _readSem;
	Semaphore _writeSem;
	Semaphore _countSem;
	unsigned int _counter;
};

#endif //_RW_LOCK_H_