/// <summary>
/// Unlinks the specified entry from this directory without actually
/// deleting it.
/// </summary>
/// <param name="entry">the entry to be unlinked</param>
/// <seealso cref="LinkEntry(FatLfnDirectoryEntry)"/>
internal void UnlinkEntry(FatLfnDirectoryEntry entry)
{
var sn = entry.RealEntry.GetShortName();
if (sn.Equals(ShortName.Dot) || sn.Equals(ShortName.DotDot))
{
throw
new ArgumentException(
"the dot entries can not be removed");
}
var lowerName = entry.GetName().ToLowerInvariant();
if (!longNameIndex.ContainsKey(lowerName))
{
throw new Exception();
}
longNameIndex.Remove(lowerName);
if (!shortNameIndex.ContainsKey(sn))
{
throw new Exception();
}
shortNameIndex.Remove(sn);
if (entry.IsFile())
{
entryToFile.Remove(entry.RealEntry);
}
else
{
entryToDirectory.Remove(entry.RealEntry);
}
}
/// <summary>
/// According to the FAT file system specification, leading and trailing
/// spaces in the name are ignored by this method.
/// </summary>
/// <param name="name"></param>
/// <returns></returns>
/// <exception cref="IOException"></exception>
public IFsDirectoryEntry AddDirectory(string name)
{
CheckWritable();
CheckUniqueName(name);
name = name.Trim();
var sn = MakeShortName(name, true);
var real = Dir.CreateSub(fat);
real.SetShortName(sn);
var e = new FatLfnDirectoryEntry(this, real, name);
try {
Dir.AddEntries(e.CompactForm());
}
catch (IOException ex) {
var cc = new ClusterChain(fat, real.GetStartCluster(), false);
cc.SetChainLength(0);
Dir.RemoveEntry(real);
throw ex;
}
shortNameIndex.Add(sn, e);
longNameIndex.Add(name.ToLowerInvariant(), e);
GetDirectory(real);
Flush();
return(e);
}
/// <summary>
/// Links the specified entry to this directory, updating the entrie's
/// short name.
/// </summary>
/// <param name="entry">the entry to be linked (added) to this directory</param>
/// <seealso cref="UnlinkEntry(FatLfnDirectoryEntry)"/>
internal void LinkEntry(FatLfnDirectoryEntry entry)
{
CheckUniqueName(entry.GetName());
ShortName name;
name = dbg.Generate83BufferNew(entry.GetName());
entry.RealEntry.SetShortName(name);
longNameIndex.Add(entry.GetName().ToLowerInvariant(), entry);
shortNameIndex.Add(entry.RealEntry.GetShortName(), entry);
UpdateLfn();
}
private void ParseLfn()
{
var i = 0;
var size = Dir.GetEntryCount();
while (i < size)
{
// jump over empty entries
while (i < size && Dir.GetEntry(i) == null)
{
i++;
}
if (i >= size)
{
break;
}
var offset = i; // beginning of the entry
// check when we reach a real entry
while (Dir.GetEntry(i).IsLfnEntry())
{
i++;
if (i >= size)
{
// This is a cutted entry, forgive it
break;
}
}
if (i >= size)
{
// This is a cutted entry, forgive it
break;
}
var current =
FatLfnDirectoryEntry.Extract(this, offset, ++i - offset);
if (!current.RealEntry.IsDeleted() && current.IsValid())
{
CheckUniqueName(current.GetName());
shortNameIndex.Add(current.RealEntry.GetShortName(), current);
longNameIndex.Add(current.GetName().ToLowerInvariant(), current);
}
}
}
/// <summary>
/// According to the FAT file system specification, leading and trailing
/// spaces in the name are ignored by this method.
/// </summary>
/// <param name="name"></param>
/// <returns></returns>
/// <exception cref="IOException"></exception>
public IFsDirectoryEntry AddFile(string name)
{
CheckWritable();
CheckUniqueName(name);
name = name.Trim();
var sn = MakeShortName(name, false);
var entry = new FatLfnDirectoryEntry(name, sn, this, false);
Dir.AddEntries(entry.CompactForm());
shortNameIndex.Add(sn, entry);
longNameIndex.Add(name.ToLowerInvariant(), entry);
GetFile(entry.RealEntry);
Dir.SetDirty();
return(entry);
}
