/// <summary>
/// Displays the pass associated with <paramref name="item"/> in the editing controls.
/// </summary>
/// <param name="item">The <see cref="ListViewItem"/> containing the pass to edit.</param>
private void DisplayPass(ListViewItem item)
{
currentPass = item;
ErasureMethodPass pass = (ErasureMethodPass)item.Tag;
passEditor.PassData = (byte[])pass.OpaqueValue;
passEditor.PassType = pass.Function == PassBasedErasureMethod.WriteRandom ?
CustomMethodPassEditorPassType.Random :
CustomMethodPassEditorPassType.Text;
}
private void passesDuplicateBtn_Click(object sender, EventArgs e)
{
//Save the current pass to prevent data loss
SavePass(currentPass);
foreach (ListViewItem item in passesLv.SelectedItems)
{
ErasureMethodPass oldPass = (ErasureMethodPass)item.Tag;
ErasureMethodPass pass = new ErasureMethodPass(
oldPass.Function, oldPass.OpaqueValue);
AddPass(pass);
}
}
protected CustomErasureMethod(SerializationInfo info, StreamingContext context)
{
Name = info.GetString("Name");
Guid = (Guid)info.GetValue("GUID", Guid.GetType());
RandomizePasses = info.GetBoolean("RandomizePasses");
List <PassData> passes = (List <PassData>)
info.GetValue("Passes", typeof(List <PassData>));
Passes = new ErasureMethodPass[passes.Count];
for (int i = 0; i != passes.Count; ++i)
{
Passes[i] = passes[i];
}
}
/// <summary>
/// Saves the currently edited pass details to memory.
/// </summary>
private void SavePass(ListViewItem item)
{
ErasureMethodPass pass = (ErasureMethodPass)item.Tag;
if (passEditor.PassType == CustomMethodPassEditorPassType.Random)
{
pass.Function = PassBasedErasureMethod.WriteRandom;
pass.OpaqueValue = null;
item.SubItems[1].Text = S._("Random Data");
}
else
{
pass.Function = PassBasedErasureMethod.WriteConstant;
pass.OpaqueValue = passEditor.PassData;
item.SubItems[1].Text = S._("Constant ({0} bytes)", passEditor.PassData.Length);
}
}
public PassData(ErasureMethodPass pass)
{
if (pass.Function == PassBasedErasureMethod.WriteConstant)
{
Random = false;
OpaqueValue = pass.OpaqueValue;
}
else if (pass.Function == PassBasedErasureMethod.WriteRandom)
{
Random = true;
}
else
{
throw new ArgumentException(S._("The custom erasure method can only comprise " +
"passes containing constant or random passes"));
}
}
/// <summary>
/// Adds the given pass to the displayed list of passes.
/// </summary>
/// <param name="pass">The pass to add.</param>
/// <returns>The item added to the list view.</returns>
private ListViewItem AddPass(ErasureMethodPass pass)
{
ListViewItem item = new ListViewItem((passesLv.Items.Count + 1).ToString(
CultureInfo.CurrentCulture));
item.Tag = pass;
if (pass.Function == PassBasedErasureMethod.WriteRandom)
{
item.SubItems.Add(S._("Random Data"));
}
else
{
item.SubItems.Add(S._("Constant ({0} bytes)", ((byte[])pass.OpaqueValue).Length));
}
passesLv.Items.Add(item);
return(item);
}
/// <summary>
/// Shuffles the passes in the input array, effectively randomizing the
/// order or rewrites.
/// </summary>
/// <param name="passes">The input set of passes.</param>
/// <returns>The shuffled set of passes.</returns>
protected static ErasureMethodPass[] ShufflePasses(ErasureMethodPass[] passes)
{
//Make a copy.
ErasureMethodPass[] result = new ErasureMethodPass[passes.Length];
passes.CopyTo(result, 0);
//Randomize.
IPrng rand = Host.Instance.Prngs.ActivePrng;
for (int i = 0; i < result.Length; ++i)
{
int val = rand.Next(result.Length - 1);
ErasureMethodPass tmpPass = result[val];
result[val] = result[i];
result[i] = tmpPass;
}
return(result);
}
private void passesAddBtn_Click(object sender, EventArgs e)
{
//Save the current pass being edited
if (currentPass != null)
{
SavePass(currentPass);
}
//Then create a new, random pass, adding it to the list
ErasureMethodPass pass = new ErasureMethodPass(PassBasedErasureMethod.WriteRandom, null);
ListViewItem item = AddPass(pass);
//If a pass is currently selected, insert the pass after the currently selected one.
if (passesLv.SelectedIndices.Count > 0)
{
item.Remove();
passesLv.Items.Insert(passesLv.SelectedIndices[passesLv.SelectedIndices.Count - 1] + 1,
item);
RenumberPasses();
}
}
