public VirtualDiskStream(string vhdPath)
{
this.vhdFile = new VhdFileFactory().Create(vhdPath);
this.blockFactory = vhdFile.GetBlockFactory();
footerRange = this.blockFactory.GetFooterRange();
fileDataRange = IndexRange.FromLength(0, this.Length - footerRange.Length);
}
public IndexRange GetFooterRange()
{
long startIndex = this.vhdFile.DataReader.Size - VhdConstants.VHD_FOOTER_SIZE;
var logicalRange = IndexRange.FromLength(startIndex, VhdConstants.VHD_FOOTER_SIZE);
return(logicalRange);
}
public override Block Create(uint block)
{
if (!vhdFile.BlockAllocationTable.HasData(block))
{
if (cachedBlock == null || cachedBlock.BlockIndex != block)
{
cachedBlock = new Block(this)
{
BlockIndex = block,
VhdUniqueId = this.vhdFile.Footer.UniqueId,
LogicalRange = IndexRange.FromLength(block * GetBlockSize(), vhdFile.Header.BlockSize),
BitMap = null,
Empty = true
};
}
return(cachedBlock);
}
if (cachedBlock == null || cachedBlock.BlockIndex != block)
{
cachedBlock = new Block(this)
{
BlockIndex = block,
VhdUniqueId = this.vhdFile.Footer.UniqueId,
LogicalRange = IndexRange.FromLength(block * GetBlockSize(), vhdFile.Header.BlockSize),
BitMap = bitMapFactory.Create(block),
Empty = false
};
}
return(cachedBlock);
}
public override Block Create(uint block)
{
if (!vhdFile.BlockAllocationTable.HasData(block))
{
if (cachedBlock == null || cachedBlock.BlockIndex != block)
{
cachedBlock = parentBlockFactory.Create(block);
}
return(cachedBlock);
}
if (cachedBlock == null || cachedBlock.BlockIndex != block)
{
IndexRange logicalRange = IndexRange.FromLength(block * GetBlockSize(), this.GetBlockSize());
if (ExtraBlockIndex.HasValue && block == ExtraBlockIndex)
{
long startIndex = block * GetBlockSize();
long size = vhdFile.Footer.CurrentSize - startIndex;
logicalRange = IndexRange.FromLength(startIndex, size);
}
cachedBlock = new Block(this)
{
BlockIndex = block,
VhdUniqueId = this.vhdFile.Footer.UniqueId,
LogicalRange = logicalRange,
BitMap = bitMapFactory.Create(block),
Empty = false
};
}
return(cachedBlock);
}
public IEnumerable <IndexRange> GetEmptyRanges()
{
var blobRange = new List <IndexRange> {
IndexRange.FromLength(0, this.Length)
};
return(IndexRange.SubstractRanges(blobRange, GetPageRanges()));
}
/// <summary>
/// Reads the specified number of bytes from the current position.
/// </summary>
public override int Read(byte[] buffer, int offset, int count)
{
if (count <= 0)
{
return(0);
}
try
{
var rangeToRead = IndexRange.FromLength(this.position, count);
int writtenCount = 0;
if (fileDataRange.Intersection(rangeToRead) == null)
{
int readCountFromFooter;
if (TryReadFromFooter(rangeToRead, buffer, offset, out readCountFromFooter))
{
writtenCount += readCountFromFooter;
}
return(writtenCount);
}
rangeToRead = fileDataRange.Intersection(rangeToRead);
var startingBlock = ByteToBlock(rangeToRead.StartIndex);
var endingBlock = ByteToBlock(rangeToRead.EndIndex);
for (var blockIndex = startingBlock; blockIndex <= endingBlock; blockIndex++)
{
var currentBlock = blockFactory.Create(blockIndex);
var rangeToReadInBlock = currentBlock.LogicalRange.Intersection(rangeToRead);
var copyStartIndex = rangeToReadInBlock.StartIndex % blockFactory.GetBlockSize();
Buffer.BlockCopy(currentBlock.Data, (int)copyStartIndex, buffer, offset + writtenCount, (int)rangeToReadInBlock.Length);
writtenCount += (int)rangeToReadInBlock.Length;
}
this.position += writtenCount;
return(writtenCount);
}
catch (Exception e)
{
throw new VhdParsingException("Invalid or Corrupted VHD file", e);
}
}
public Block Create(uint block)
{
if (!this.HasData(block))
{
if (cachedBlock == null || cachedBlock.BlockIndex != block)
{
IndexRange logicalRange = IndexRange.FromLength(block * GetBlockSize(), this.GetBlockSize());
if (extraBlockIndex.HasValue && block == extraBlockIndex)
{
long startIndex = block * GetBlockSize();
long size = this.vhdFile.DataReader.Size - startIndex - VhdConstants.VHD_FOOTER_SIZE;
logicalRange = IndexRange.FromLength(startIndex, size);
}
cachedBlock = new Block(this)
{
BlockIndex = block,
VhdUniqueId = this.vhdFile.Footer.UniqueId,
LogicalRange = logicalRange,
BitMap = null,
Empty = true
};
}
return(cachedBlock);
}
if (cachedBlock == null || cachedBlock.BlockIndex != block)
{
IndexRange logicalRange = IndexRange.FromLength(block * GetBlockSize(), this.GetBlockSize());
if (extraBlockIndex.HasValue && block == extraBlockIndex)
{
long startIndex = block * GetBlockSize();
long size = this.vhdFile.DataReader.Size - startIndex - VhdConstants.VHD_FOOTER_SIZE;
logicalRange = IndexRange.FromLength(startIndex, size);
}
cachedBlock = new Block(this)
{
BlockIndex = block,
VhdUniqueId = this.vhdFile.Footer.UniqueId,
LogicalRange = logicalRange,
Empty = false
};
}
return(cachedBlock);
}
public IndexRange GetFooterRange()
{
return(IndexRange.FromLength(this.GetBlockSize() * this.BlockCount, VhdConstants.VHD_FOOTER_SIZE));
}
public IndexRange GetFooterRange()
{
return(IndexRange.FromLength(this.vhdFile.Footer.CurrentSize, VhdConstants.VHD_FOOTER_SIZE));
}
