Adds SymLinks.ps1

Author: alexpilotti

SymLinks.ps1

@@ -0,0 +1,58 @@
+$code = @"
+using System;
+using System.Text;
+using System.Runtime.InteropServices;
+using Microsoft.Win32.SafeHandles;
+using System.ComponentModel;
+
+namespace SymLinkInterop {
+	public sealed class SymLinkManager
+	{
+		private const int FILE_SHARE_READ = 1;
+		private const int FILE_SHARE_WRITE = 2;
+
+		private const int CREATION_DISPOSITION_OPEN_EXISTING = 3;
+
+		private const int FILE_FLAG_BACKUP_SEMANTICS = 0x02000000;
+
+		[DllImport("kernel32.dll", EntryPoint = "GetFinalPathNameByHandleW", CharSet = CharSet.Unicode, SetLastError = true)]
+		public static extern int GetFinalPathNameByHandle(IntPtr handle, [In, Out] StringBuilder path, int bufLen, int flags);
+
+		[DllImport("kernel32.dll", EntryPoint = "CreateFileW", CharSet = CharSet.Unicode, SetLastError = true)]
+		public static extern SafeFileHandle CreateFile(string lpFileName, int dwDesiredAccess, int dwShareMode,
+		IntPtr SecurityAttributes, int dwCreationDisposition, int dwFlagsAndAttributes, IntPtr hTemplateFile);
+
+		public static string GetSymbolicLinkTarget(string symlinkpath)
+		{
+			SafeFileHandle directoryHandle = CreateFile(symlinkpath, 0, 2, System.IntPtr.Zero, CREATION_DISPOSITION_OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, System.IntPtr.Zero);
+			if(directoryHandle.IsInvalid)
+				throw new Win32Exception(Marshal.GetLastWin32Error());
+
+			StringBuilder path = new StringBuilder(512);
+			int size = GetFinalPathNameByHandle(directoryHandle.DangerousGetHandle(), path, path.Capacity, 0);
+			if (size<0)
+				throw new Win32Exception(Marshal.GetLastWin32Error());
+			if (path[0] == '\\' && path[1] == '\\' && path[2] == '?' && path[3] == '\\')
+				return path.ToString().Substring(4);
+			else
+				return path.ToString();
+		}
+	}
+}
+"@
+
+Add-Type -TypeDefinition $code
+
+function Get-SymbolicLinkTarget
+{
+    [CmdletBinding()]
+    param
+    (
+        [parameter(Mandatory=$true, ValueFromPipeline=$true)]
+        [string]$Path
+    )
+    PROCESS
+    {
+		return [SymLinkInterop.SymLinkManager]::GetSymbolicLinkTarget($Path)
+	}
+}