/// <summary>
/// Writes data to this cluster chain, possibly growing the chain so it
/// can store the additional data. When this method returns without throwing
/// an exception, the buffer's <see cref="MemoryStream.Position"/> will
/// equal it's <see cref="MemoryStream.Length"/>, and the length will not
/// have changed. This is not guaranteed if writing fails.
/// </summary>
/// <param name="offset">the offset where to write the first byte from the buffer</param>
/// <param name="srcBuf">the buffer to write to this <see cref="ClusterChain"/></param>
/// <exception cref="IOException">IOException on write error</exception>
public void WriteData(long offset, MemoryStream srcBuf)
{
var len = (int)(srcBuf.Length - srcBuf.Position);
if (len == 0)
{
return;
}
var minSize = offset + len;
if (GetLengthOnDisk() < minSize)
{
SetSize(minSize);
}
var chain = fat.GetChain(GetStartCluster());
var chainIdx = (int)(offset / clusterSize);
if (offset % clusterSize != 0)
{
var clusOfs = (int)(offset % clusterSize);
var size = Math.Min(len,
(int)(clusterSize - (offset % clusterSize)));
srcBuf.SetLength(srcBuf.Position + size);
device.Write(GetDevOffset(chain[chainIdx], clusOfs), srcBuf);
offset += size;
len -= size;
chainIdx++;
}
while (len > 0)
{
var size = Math.Min(clusterSize, len);
srcBuf.SetLength(srcBuf.Position + size);
device.Write(GetDevOffset(chain[chainIdx], 0), srcBuf);
len -= size;
chainIdx++;
}
}
/// <summary>
/// Writes a copy of this boot sector to the specified device, if a copy
/// is requested.
/// </summary>
/// <param name="device">the device to write the boot sector copy to</param>
/// <exception cref="System.IO.IOException">IOException on write error</exception>
/// <seealso cref="GetBootSectorCopySector"/>
public void WriteCopy(IBlockDevice device)
{
if (GetBootSectorCopySector() > 0)
{
long offset = GetBootSectorCopySector() * SIZE;
Buffer.Position = 0;
device.Write(offset, Buffer);
}
}
/// <summary>
/// Write the contents of this FAT to the given device at the given offset.
/// </summary>
/// <param name="offset">the device offset where to write the FAT copy</param>
/// <exception cref="IOException">IOException on write error</exception>
public void WriteCopy(long offset)
{
var data = new byte[sectorCount * sectorSize];
for (var index = 0; index < entries.Length; index++)
{
fatType.WriteEntry(data, index, entries[index]);
}
device.Write(offset, new MemoryStream(data));
}
public void Write()
{
if (!IsDirty())
{
return;
}
Buffer.Position = 0;
device.Write(offset, Buffer);
dirty = false;
}
protected override void Write(MemoryStream data)
{
device.Write(deviceOffset, data);
}