src/system/boot/loader/file_systems/fat/CachedBlock.h

   1 /*
   2  * Copyright 2008, Haiku, Inc.
   3  * Distributed under the terms of the MIT License.
   4  *
   5  * Authors:
   6  *              François Revol <revol@free.fr>
   7  */
   8 #ifndef CACHED_BLOCK_H
   9 #define CACHED_BLOCK_H
  10
  11
  12 #include "Volume.h"
  13
  14
  15 namespace FATFS {
  16
  17
  18 class CachedBlock {
  19         public:
  20                 enum {
  21                         READ    = 0x01,
  22                         CLEAR   = 0x02,
  23                         FORCE   = 0x04,
  24                 };
  25
  26         public:
  27                 CachedBlock(Volume &volume);
  28                 CachedBlock(Volume &volume, off_t block);
  29                 ~CachedBlock();
  30
  31                 uint8 *SetTo(off_t block);
  32                 status_t SetTo(off_t blockNumber, uint32 flags);
  33                 status_t Flush();
  34
  35                 void Unset();
  36
  37                 uint8 *Block() const { return fBlock; }
  38                 off_t BlockNumber() const { return fBlockNumber; }
  39                 uint32 BlockSize() const { return fVolume.BlockSize(); }
  40                 uint32 BlockShift() const { return fVolume.BlockShift(); }
  41
  42         private:
  43                 Volume  &fVolume;
  44                 off_t   fBlockNumber;
  45                 uint8   *fBlock;
  46 };
  47
  48
  49 inline void
  50 CachedBlock::Unset()
  51 {
  52         fBlockNumber = -1;
  53 }
  54
  55
  56 }       // namespace FATFS
  57
  58
  59 #endif  /* CACHED_BLOCK_H */