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#ifndef VISUAL_VCACHE_H
#define VISUAL_VCACHE_H
// Copyright (c) 2000, 2001, 2002, 2003 by David Scherer and others.
// See the file license.txt for complete license terms.
// See the file authors.txt for a complete list of contributors.
#include "platform.h"
namespace visual {
class Cache
{
public:
typedef lock<mutex> read_lock;
typedef counted_lock<mutex> write_lock;
mutex mtx;
Cache();
Cache( const Cache& other);
virtual ~Cache();
void updateCache();
// Called to ensure that the cache is up to date.
// The caller should hold a read_lock or write_lock first!
int lastChange();
// returns a number that increases when write_lock is taken.
protected:
virtual void refreshCache() = 0;
// Called by updateCache() when the cache needs to be refreshed.
// Returns true if the object should remain in its container, and false
// otherwise.
int lastRefresh; // lastChange() when refreshCache() was last called
};
} // !namespace visual
#endif // !VISUAL_VCACHE_H
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