public static void CreateJunction(string junctionPoint, string targetDir, bool overwrite)
{
targetDir = Path.GetFullPath(targetDir);
if (!Directory.Exists(targetDir))
{
Directory.CreateDirectory(targetDir);
}
if (Directory.Exists(junctionPoint))
{
if (!overwrite)
{
throw new IOException("Directory already exists and overwrite parameter is false.");
}
}
else
{
Directory.CreateDirectory(junctionPoint);
}
using (SafeFileHandle handle = NativeMethods.OpenReparsePoint(junctionPoint, NativeMethods.EFileAccess.GenericWrite))
{
byte[] targetDirBytes = Encoding.Unicode.GetBytes(NonInterpretedPathPrefix + Path.GetFullPath(targetDir));
NativeMethods.REPARSE_DATA_BUFFER reparseDataBuffer = new NativeMethods.REPARSE_DATA_BUFFER();
reparseDataBuffer.ReparseTag = NativeMethods.IO_REPARSE_TAG_MOUNT_POINT;
reparseDataBuffer.ReparseDataLength = (ushort)(targetDirBytes.Length + 12);
reparseDataBuffer.SubstituteNameOffset = 0;
reparseDataBuffer.SubstituteNameLength = (ushort)targetDirBytes.Length;
reparseDataBuffer.PrintNameOffset = (ushort)(targetDirBytes.Length + 2);
reparseDataBuffer.PrintNameLength = 0;
reparseDataBuffer.PathBuffer = new byte[0x3ff0];
Array.Copy(targetDirBytes, reparseDataBuffer.PathBuffer, targetDirBytes.Length);
int inBufferSize = Marshal.SizeOf(reparseDataBuffer);
IntPtr inBuffer = Marshal.AllocHGlobal(inBufferSize);
try
{
Marshal.StructureToPtr(reparseDataBuffer, inBuffer, false);
int bytesReturned;
bool result = NativeMethods.DeviceIoControl(handle.DangerousGetHandle(), NativeMethods.FSCTL_SET_REPARSE_POINT,
inBuffer, targetDirBytes.Length + 20, IntPtr.Zero, 0, out bytesReturned, IntPtr.Zero);
if (!result)
{
NativeMethods.ThrowLastWin32Error("Unable to create junction point.");
}
}
finally
{
Marshal.FreeHGlobal(inBuffer);
}
}
}
public static bool InternalDelete(string path, LinkType type)
{
if (type == LinkType.None)
{
return(false);
}
if (!Directory.Exists(path))
{
if (File.Exists(path))
{
throw new IOException("Path is not a junction point.");
}
return(false);
}
using (SafeFileHandle handle = NativeMethods.OpenReparsePoint(path, NativeMethods.EFileAccess.GenericWrite))
{
NativeMethods.REPARSE_DATA_BUFFER reparseDataBuffer = new NativeMethods.REPARSE_DATA_BUFFER();
reparseDataBuffer.ReparseTag = type == LinkType.Junction ? NativeMethods.IO_REPARSE_TAG_MOUNT_POINT : NativeMethods.IO_REPARSE_TAG_SYM_LINK;
reparseDataBuffer.ReparseDataLength = 0;
reparseDataBuffer.PathBuffer = new byte[0x3ff0];
int inBufferSize = Marshal.SizeOf(reparseDataBuffer);
IntPtr inBuffer = Marshal.AllocHGlobal(inBufferSize);
try
{
Marshal.StructureToPtr(reparseDataBuffer, inBuffer, false);
int bytesReturned;
bool result = NativeMethods.DeviceIoControl(handle.DangerousGetHandle(), NativeMethods.FSCTL_DELETE_REPARSE_POINT,
inBuffer, 8, IntPtr.Zero, 0, out bytesReturned, IntPtr.Zero);
if (!result)
{
NativeMethods.ThrowLastWin32Error("Unable to delete junction point.");
}
}
finally
{
Marshal.FreeHGlobal(inBuffer);
}
try
{
Directory.Delete(path);
return(true);
}
catch (IOException ex)
{
throw new IOException("Unable to delete junction point.", ex);
}
}
}
private static string InternalGetTarget(SafeFileHandle handle, out LinkType type)
{
int outBufferSize = Marshal.SizeOf(typeof(NativeMethods.REPARSE_DATA_BUFFER));
IntPtr outBuffer = Marshal.AllocHGlobal(outBufferSize);
type = LinkType.None;
try
{
int bytesReturned;
bool result = NativeMethods.DeviceIoControl(handle.DangerousGetHandle(), NativeMethods.FSCTL_GET_REPARSE_POINT,
IntPtr.Zero, 0, outBuffer, outBufferSize, out bytesReturned, IntPtr.Zero);
if (!result)
{
int error = Marshal.GetLastWin32Error();
if (error == NativeMethods.ERROR_NOT_A_REPARSE_POINT)
{
return(null);
}
NativeMethods.ThrowLastWin32Error("Unable to get information about junction point.");
}
NativeMethods.REPARSE_DATA_BUFFER reparseDataBuffer = (NativeMethods.REPARSE_DATA_BUFFER)
Marshal.PtrToStructure(outBuffer, typeof(NativeMethods.REPARSE_DATA_BUFFER));
if (reparseDataBuffer.ReparseTag == NativeMethods.IO_REPARSE_TAG_MOUNT_POINT)
{
type = LinkType.Junction;
string targetDir = Encoding.Unicode.GetString(reparseDataBuffer.PathBuffer,
reparseDataBuffer.SubstituteNameOffset, reparseDataBuffer.SubstituteNameLength);
if (targetDir.StartsWith(NonInterpretedPathPrefix))
{
targetDir = targetDir.Substring(NonInterpretedPathPrefix.Length);
}
return(targetDir);
}
else if (reparseDataBuffer.ReparseTag == NativeMethods.IO_REPARSE_TAG_SYM_LINK)
{
type = LinkType.Symbolic;
string targetDir = Encoding.Unicode.GetString(reparseDataBuffer.PathBuffer,
reparseDataBuffer.PrintNameOffset + 4, reparseDataBuffer.PrintNameLength);
if (targetDir.StartsWith(NonInterpretedPathPrefix))
{
targetDir = targetDir.Substring(NonInterpretedPathPrefix.Length);
}
return(targetDir);
}
return(null);
}
finally
{
Marshal.FreeHGlobal(outBuffer);
}
}
