61 lines
1.6 KiB
C
61 lines
1.6 KiB
C
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///////////////////////////////////////////////////////////////////////////////
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//
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// Copyright (c) 1998, Microsoft Corp. All rights reserved.
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//
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// FILE
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//
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// Perimeter.h
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//
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// SYNOPSIS
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//
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// This file describes the class Perimeter.
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//
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// MODIFICATION HISTORY
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//
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// 09/04/1997 Original version.
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//
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///////////////////////////////////////////////////////////////////////////////
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#ifndef _PERIMETER_H_
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#define _PERIMETER_H_
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///////////////////////////////////////////////////////////////////////////////
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//
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// CLASS
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//
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// Perimeter
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//
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// DESCRIPTION
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//
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// This class implements a Perimeter synchronization object. Threads
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// may request either exclusive or shared access to the protected area.
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//
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///////////////////////////////////////////////////////////////////////////////
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class Perimeter
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{
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public:
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Perimeter() throw ();
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~Perimeter() throw ();
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void Lock() throw ();
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void LockExclusive() throw ();
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void Unlock() throw ();
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protected:
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LONG sharing; // Number of threads sharing the perimiter.
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LONG waiting; // Number of threads waiting for shared access.
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PLONG count; // Pointer to either sharing or waiting depending
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// on the current state of the perimiter.
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CRITICAL_SECTION exclusive; // Synchronizes exclusive access.
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HANDLE sharedOK; // Wakes up threads waiting for shared.
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HANDLE exclusiveOK; // Wakes up threads waiting for exclusive.
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private:
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// Not implemented.
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Perimeter(const Perimeter&) throw ();
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Perimeter& operator=(const Perimeter&) throw ();
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};
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#endif // _PERIMETER_H_
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