allow FileStream to open any types of files from path

src/libraries/System.IO.FileSystem/tests/FileStream/FileStreamConformanceTests.Windows.cs

@@ -23,7 +23,7 @@ protected override async Task<StreamPair> CreateConnectedStreamsAsync()
             string pipePath = Path.GetFullPath($@"\\.\pipe\{pipeName}");
 
             var server = new NamedPipeServerStream(pipeName, PipeDirection.In);
-            var clienStream = new FileStream(File.OpenHandle(pipePath, FileMode.Open, FileAccess.Write, FileShare.None), FileAccess.Write);
+            var clienStream = new FileStream(pipePath, FileMode.Open, FileAccess.Write, FileShare.None);
 
             await server.WaitForConnectionAsync();
 

src/libraries/System.Private.CoreLib/src/System/IO/Strategies/FileStreamHelpers.Windows.cs

@@ -142,32 +142,6 @@ internal static void Unlock(SafeFileHandle handle, string? path, long position,
             }
         }
 
-        internal static void ValidateFileTypeForNonExtendedPaths(SafeFileHandle handle, string originalPath)
-        {
-            if (!PathInternal.IsExtended(originalPath))
-            {
-                // To help avoid stumbling into opening COM/LPT ports by accident, we will block on non file handles unless
-                // we were explicitly passed a path that has \\?\. GetFullPath() will turn paths like C:\foo\con.txt into
-                // \\.\CON, so we'll only allow the \\?\ syntax.
-
-                int fileType = handle.GetFileType();
-                if (fileType != Interop.Kernel32.FileTypes.FILE_TYPE_DISK)
-                {
-                    int errorCode = fileType == Interop.Kernel32.FileTypes.FILE_TYPE_UNKNOWN
-                        ? Marshal.GetLastPInvokeError()
-                        : Interop.Errors.ERROR_SUCCESS;
-
-                    handle.Dispose();
-
-                    if (errorCode != Interop.Errors.ERROR_SUCCESS)
-                    {
-                        throw Win32Marshal.GetExceptionForWin32Error(errorCode);
-                    }
-                    throw new NotSupportedException(SR.NotSupported_FileStreamOnNonFiles);
-                }
-            }
-        }
-
         internal static unsafe void SetFileLength(SafeFileHandle handle, string? path, long length)
         {
             var eofInfo = new Interop.Kernel32.FILE_END_OF_FILE_INFO
@@ -188,8 +162,6 @@ internal static unsafe void SetFileLength(SafeFileHandle handle, string? path, l
             }
         }
 
-
-
         internal static async Task AsyncModeCopyToAsync(SafeFileHandle handle, string? path, bool canSeek, long filePosition, Stream destination, int bufferSize, CancellationToken cancellationToken)
         {
             // For efficiency, we avoid creating a new task and associated state for each asynchronous read.

src/libraries/System.Private.CoreLib/src/System/IO/Strategies/Net5CompatFileStreamStrategy.Windows.cs

@@ -46,8 +46,6 @@ internal sealed partial class Net5CompatFileStreamStrategy : FileStreamStrategy
 
         private void Init(FileMode mode, string originalPath, FileOptions options)
         {
-            FileStreamHelpers.ValidateFileTypeForNonExtendedPaths(_fileHandle, originalPath);
-
             Debug.Assert(!_useAsyncIO || _fileHandle.ThreadPoolBinding != null);
 
             // For Append mode...

src/libraries/System.Private.CoreLib/src/System/IO/Strategies/WindowsFileStreamStrategy.cs

@@ -54,7 +54,7 @@ internal WindowsFileStreamStrategy(string path, FileMode mode, FileAccess access
 
             try
             {
-                Init(mode, path);
+                Init(mode);
             }
             catch
             {
@@ -230,10 +230,8 @@ public sealed override long Seek(long offset, SeekOrigin origin)
 
         internal sealed override void Unlock(long position, long length) => FileStreamHelpers.Unlock(_fileHandle, _path, position, length);
 
-        private void Init(FileMode mode, string originalPath)
+        private void Init(FileMode mode)
         {
-            FileStreamHelpers.ValidateFileTypeForNonExtendedPaths(_fileHandle, originalPath);
-
             // For Append mode...
             if (mode == FileMode.Append)
             {