private void EraseUnusedSpace(VolumeInfo volInfo, DirectoryInfo info, IFileSystem fsInfo,
IErasureMethod method)
{
ProgressManager mainProgress = new ProgressManager();
Progress.Steps.Add(new SteppedProgressManagerStep(mainProgress,
EraseClusterTips ? 0.8f : 0.9f, S._("Erasing unused space...")));
//Continue creating files while there is free space.
while (volInfo.AvailableFreeSpace > 0)
{
//Generate a non-existant file name
string currFile = FileSystemBase.GenerateRandomFileName(info, 18);
//Create the stream
FileStream stream = new FileStream(currFile, FileMode.CreateNew,
FileAccess.Write, FileShare.None, 8, FileOptions.WriteThrough);
try
{
//Set the length of the file to be the amount of free space left
//or the maximum size of one of these dumps.
mainProgress.Total = mainProgress.Completed +
method.CalculateEraseDataSize(null, volInfo.AvailableFreeSpace);
long streamLength = Math.Min(PassBasedErasureMethod.FreeSpaceFileUnit,
volInfo.AvailableFreeSpace);
//Handle IO exceptions gracefully, because the filesystem
//may require more space than demanded by us for file allocation.
while (true)
{
try
{
stream.SetLength(streamLength);
break;
}
catch (IOException)
{
if (streamLength > volInfo.ClusterSize)
{
streamLength -= volInfo.ClusterSize;
}
else
{
throw;
}
}
}
//Then run the erase task
method.Erase(stream, long.MaxValue, Host.Instance.Prngs.ActivePrng,
delegate(long lastWritten, long totalData, int currentPass)
{
mainProgress.Completed += lastWritten;
mainProgress.Tag = new int[] { currentPass, method.Passes };
if (Task.Canceled)
{
throw new OperationCanceledException(S._("The task was cancelled."));
}
}
);
}
finally
{
stream.Close();
fsInfo.ResetFileTimes(new FileInfo(currFile));
}
}
//Mark the main bulk of the progress as complete
mainProgress.MarkComplete();
}
public override void Execute()
{
//Check for sufficient privileges to run the unused space erasure.
if (!Security.IsAdministrator())
{
if (Environment.OSVersion.Platform == PlatformID.Win32NT &&
Environment.OSVersion.Version >= new Version(6, 0))
{
Logger.Log(S._("The program does not have the required permissions to erase " +
"the unused space on disk. Run the program as an administrator and retry " +
"the operation."), LogLevel.Error);
}
else
{
Logger.Log(S._("The program does not have the required permissions to erase " +
"the unused space on disk."), LogLevel.Error);
}
return;
}
//Check whether System Restore has any available checkpoints.
if (SystemRestore.GetInstances().Count != 0)
{
Logger.Log(S._("This computer has had System Restore or Volume Shadow Copies " +
"enabled. This may allow copies of files stored on the disk to be recovered " +
"and pose a security concern.", Drive), LogLevel.Warning);
}
//If the user is under disk quotas, log a warning message
if (VolumeInfo.FromMountPoint(Drive).HasQuota)
{
Logger.Log(S._("The drive {0} has disk quotas active. This will prevent the " +
"complete erasure of unused space and may pose a security concern.",
Drive), LogLevel.Warning);
}
//Get the erasure method if the user specified he wants the default.
IErasureMethod method = EffectiveMethod;
//Make a folder to dump our temporary files in
DirectoryInfo info = new DirectoryInfo(Drive);
VolumeInfo volInfo = VolumeInfo.FromMountPoint(Drive);
IFileSystem fsManager = Host.Instance.FileSystems[volInfo];
//Start sampling the speed of the task.
Progress = new SteppedProgressManager();
//Erase the cluster tips of every file on the drive.
if (EraseClusterTips)
{
//Define the callback handlers
ProgressManager tipSearch = new ProgressManager();
tipSearch.MarkIndeterminate();
Progress.Steps.Add(new SteppedProgressManagerStep(tipSearch,
0.0f, S._("Searching for files' cluster tips...")));
ClusterTipsSearchProgress searchProgress = delegate(string path)
{
if (Task.Canceled)
{
throw new OperationCanceledException(S._("The task was cancelled."));
}
tipSearch.Tag = path;
};
ProgressManager tipProgress = new ProgressManager();
Progress.Steps.Add(new SteppedProgressManagerStep(tipProgress, 0.1f,
S._("Erasing cluster tips...")));
ClusterTipsEraseProgress eraseProgress =
delegate(int currentFile, int totalFiles, string currentFilePath)
{
tipSearch.MarkComplete();
tipProgress.Total = totalFiles;
tipProgress.Completed = currentFile;
tipProgress.Tag = currentFilePath;
if (Task.Canceled)
{
throw new OperationCanceledException(S._("The task was cancelled."));
}
};
//Start counting statistics
fsManager.EraseClusterTips(VolumeInfo.FromMountPoint(Drive),
method, searchProgress, eraseProgress);
tipProgress.MarkComplete();
}
bool lowDiskSpaceNotifications = Shell.LowDiskSpaceNotificationsEnabled;
info = info.CreateSubdirectory(Path.GetFileName(
FileSystemBase.GenerateRandomFileName(info, 18)));
try
{
//Set the folder's compression flag off since we want to use as much
//space as possible
if (info.IsCompressed())
{
info.Uncompress();
}
//Disable the low disk space notifications
Shell.LowDiskSpaceNotificationsEnabled = false;
//Fill the disk
EraseUnusedSpace(volInfo, info, fsManager, method);
//Erase old resident file system table files
ProgressManager residentProgress = new ProgressManager();
Progress.Steps.Add(new SteppedProgressManagerStep(residentProgress,
0.05f, S._("Old resident file system table files")));
fsManager.EraseOldFileSystemResidentFiles(volInfo, info, method,
delegate(int currentFile, int totalFiles)
{
residentProgress.Completed = currentFile;
residentProgress.Total = totalFiles;
if (Task.Canceled)
{
throw new OperationCanceledException(S._("The task was cancelled."));
}
}
);
residentProgress.MarkComplete();
}
finally
{
//Remove the folder holding all our temporary files.
ProgressManager tempFiles = new ProgressManager();
Progress.Steps.Add(new SteppedProgressManagerStep(tempFiles,
0.0f, S._("Removing temporary files...")));
fsManager.DeleteFolder(info, true);
tempFiles.MarkComplete();
//Reset the low disk space notifications
Shell.LowDiskSpaceNotificationsEnabled = lowDiskSpaceNotifications;
}
//Then clean the old file system entries
ProgressManager structureProgress = new ProgressManager();
Progress.Steps.Add(new SteppedProgressManagerStep(structureProgress,
0.05f, S._("Erasing unused directory structures...")));
fsManager.EraseDirectoryStructures(volInfo,
delegate(int currentFile, int totalFiles)
{
if (Task.Canceled)
{
throw new OperationCanceledException(S._("The task was cancelled."));
}
//Compute the progress
structureProgress.Total = totalFiles;
structureProgress.Completed = currentFile;
}
);
structureProgress.MarkComplete();
Progress = null;
}