profuse/Cache/ConcreteBlockCache.h
2011-02-15 04:00:54 +00:00

71 lines
1.3 KiB
C++

#ifndef __CONCRETE_BLOCK_CACHE_H__
#define __CONCRETE_BLOCK_CACHE_H__
#include <vector>
#include <Cache/BlockCache.h>
namespace Device {
class ConcreteBlockCache : public BlockCache {
public:
ConcreteBlockCache(BlockDevice *device, unsigned size = 16);
virtual ~ConcreteBlockCache();
virtual void sync();
virtual void write(unsigned block, const void *vp);
virtual void *acquire(unsigned block);
virtual void release(unsigned block, int flags);
virtual void markDirty(unsigned block);
private:
struct Entry {
unsigned block;
unsigned count;
bool dirty;
struct Entry *next;
struct Entry *prev;
struct Entry *nextHash;
uint8_t buffer[512];
};
typedef std::vector<Entry *>::iterator EntryIter;
enum { HashTableSize = 23 };
std::vector<Entry *>_buffers;
Entry *_hashTable[HashTableSize];
Entry *_first;
Entry *_last;
unsigned hashFunction(unsigned block);
Entry *findEntry(unsigned block);
void removeEntry(unsigned block);
void addEntry(Entry *);
Entry *newEntry(unsigned block);
void pushEntry(Entry *);
void setLast(Entry *);
void setFirst(Entry *);
void incrementCount(Entry *);
void decrementCount(Entry *);
};
}
#endif