* Copyright 2001-2010, Haiku Inc. All rights reserved.
* This file may be used under the terms of the MIT License.
*
* Authors:
* Janito V. Ferreira Filho
*/
#ifndef BITMAPBLOCK_H
#define BITMAPBLOCK_H
#include "CachedBlock.h"
class BitmapBlock : public CachedBlock {
public:
BitmapBlock(Volume* volume, uint32 numBits);
~BitmapBlock();
bool SetTo(off_t block);
bool SetToWritable(Transaction& transaction,
off_t block, bool empty = false);
bool CheckMarked(uint32 start, uint32 length);
bool CheckUnmarked(uint32 start, uint32 length);
bool Mark(uint32 start, uint32 length,
bool force = false);
bool Unmark(uint32 start, uint32 length,
bool force = false);
void FindNextMarked(uint32& pos);
void FindNextUnmarked(uint32& pos);
void FindPreviousMarked(uint32& pos);
void FindLargestUnmarkedRange(uint32& start,
uint32& length);
uint32 NumBits() const { return fNumBits; }
uint32 Checksum(uint32 unitsPerGroup) const;
private:
bool _Check(uint32 start, uint32 length, bool marked);
void _FindNext(uint32& pos, bool marked);
bool _Update(uint32 start, uint32 length, bool mark,
bool force);
Volume* fVolume;
uint32* fData;
const uint32* fReadOnlyData;
uint32 fNumBits;
uint32 fMaxIndex;
};
inline bool
BitmapBlock::CheckUnmarked(uint32 start, uint32 length)
{
return _Check(start, length, false);
}
inline bool
BitmapBlock::CheckMarked(uint32 start, uint32 length)
{
return _Check(start, length, true);
}
inline bool
BitmapBlock::Mark(uint32 start, uint32 length, bool force)
{
return _Update(start, length, true, force);
}
inline bool
BitmapBlock::Unmark(uint32 start, uint32 length, bool force)
{
return _Update(start, length, false, force);
}
inline void
BitmapBlock::FindNextMarked(uint32& pos)
{
_FindNext(pos, true);
}
inline void
BitmapBlock::FindNextUnmarked(uint32& pos)
{
_FindNext(pos, false);
}
#endif
