public void Truncate(ulong newLengthInBytes)
{
long clustersToKeep = (long)Math.Ceiling((double)newLengthInBytes / m_volume.BytesPerCluster);
if (clustersToKeep < ClusterCount)
{
KeyValuePairList <long, long> clustersToDeallocate = m_attributeRecord.DataRunSequence.TranslateToLCN(clustersToKeep, ClusterCount - clustersToKeep);
m_attributeRecord.DataRunSequence.Truncate(clustersToKeep);
m_attributeRecord.HighestVCN = clustersToKeep - 1;
m_attributeRecord.AllocatedLength = (ulong)(clustersToKeep * m_volume.BytesPerCluster);
foreach (KeyValuePair <long, long> runToDeallocate in clustersToDeallocate)
{
m_volume.DeallocateClusters(runToDeallocate.Key, runToDeallocate.Value);
}
}
m_attributeRecord.FileSize = newLengthInBytes;
if (m_attributeRecord.ValidDataLength > newLengthInBytes)
{
m_attributeRecord.ValidDataLength = newLengthInBytes;
}
if (m_fileRecord != null)
{
m_volume.UpdateFileRecord(m_fileRecord);
}
}
public void Truncate(ulong newLengthInBytes)
{
long clustersToKeep = (long)Math.Ceiling((double)newLengthInBytes / m_volume.BytesPerCluster);
if (clustersToKeep < ClusterCount)
{
KeyValuePairList <long, long> clustersToDeallocate = m_attributeRecord.DataRunSequence.TranslateToLCN(clustersToKeep, ClusterCount - clustersToKeep);
m_attributeRecord.DataRunSequence.Truncate(clustersToKeep);
m_attributeRecord.HighestVCN = clustersToKeep - 1;
m_attributeRecord.AllocatedLength = (ulong)(clustersToKeep * m_volume.BytesPerCluster);
foreach (KeyValuePair <long, long> runToDeallocate in clustersToDeallocate)
{
m_volume.DeallocateClusters(runToDeallocate.Key, runToDeallocate.Value);
}
}
m_attributeRecord.FileSize = newLengthInBytes;
if (m_attributeRecord.ValidDataLength > newLengthInBytes)
{
m_attributeRecord.ValidDataLength = newLengthInBytes;
}
if (m_fileRecord != null)
{
if (m_attributeRecord.AttributeType == AttributeType.Data && m_attributeRecord.Name == String.Empty)
{
// Windows NTFS v5.1 driver updates the value of the AllocatedLength field but does not usually update the value of
// the FileSize field belonging to the FileNameRecords that are stored in the FileRecord, which is likely to be 0.
List <FileNameRecord> fileNameRecords = m_fileRecord.FileNameRecords;
foreach (FileNameRecord fileNameRecord in fileNameRecords)
{
fileNameRecord.AllocatedLength = m_attributeRecord.AllocatedLength;
}
}
m_volume.UpdateFileRecord(m_fileRecord);
}
}
