public byte[] ReadMap(out int bitmapSizeInBits)
{
byte[] firstBlockBytes = _disk.ReadAllBytesFromBlock(_freeSpaceMapStartingBlock);
var stream = new MemoryStream(firstBlockBytes);
var binaryReader = new BinaryReader(stream);
int freeSpaceLengthInBits = binaryReader.ReadInt32();
int freeSpaceLengthInBytes = SpaceRequirementsCalculator.GetNumberOfChunksNeededToStoreData(
freeSpaceLengthInBits, Constants.NumberOfBitsInByte);
ReadOnlyCollection <BucketDistribution> numberOfBytesToReadFromEachBlock = ItemDistributor.Distribute(freeSpaceLengthInBytes,
_disk.BlockSizeInBytes - Constants.BlockReferenceSizeInBytes,
_disk.BlockSizeInBytes);
var freeSpaceMap = new byte[freeSpaceLengthInBytes];
int numberOfCurrentBlock = _freeSpaceMapStartingBlock;
int initialArrayPosition = 0;
foreach (BucketDistribution distribution in numberOfBytesToReadFromEachBlock)
{
byte[] newArray = _disk.ReadBytesFromBlock(numberOfCurrentBlock + distribution.BucketIndex, distribution.IndexOfFirstItemTheBucketGot,
distribution.NumberOfItemsDistributed);
Array.Copy(newArray, 0, freeSpaceMap, initialArrayPosition, distribution.NumberOfItemsDistributed);
initialArrayPosition += distribution.NumberOfItemsDistributed;
}
bitmapSizeInBits = freeSpaceLengthInBits;
return(freeSpaceMap);
}
public byte[] ReadAll()
{
byte[] bytesRead = _disk.ReadBytesFromBlock(BlockIndex, 0, this.OccupiedSpaceInBytes);
return(bytesRead);
}
