FileStreamStrategies refactor

src/libraries/System.IO.FileSystem/tests/LegacyTests/runtimeconfig.template.json

@@ -1,5 +1,5 @@
 {
  "configProperties": {
- "System.IO.UseLegacyFileStream": true
+ "System.IO.UseNet5CompatFileStream": false
  }
 }

src/libraries/System.IO/tests/LegacyTests/runtimeconfig.template.json

@@ -1,5 +1,5 @@
 {
  "configProperties": {
- "System.IO.UseLegacyFileStream": true
+ "System.IO.UseNet5CompatFileStream": false
  }
 }

src/libraries/System.Private.CoreLib/src/System.Private.CoreLib.Shared.projitems

@@ -392,8 +392,6 @@
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\BinaryReader.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\BinaryWriter.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\BufferedStream.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\BufferedFileStreamStrategy.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\DerivedFileStreamStrategy.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\DirectoryNotFoundException.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\EncodingCache.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\EndOfStreamException.cs" />
@@ -405,12 +403,10 @@
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileOptions.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileShare.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStream.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStreamStrategy.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\HandleInheritability.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\InvalidDataException.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\IOException.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\MemoryStream.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\LegacyFileStreamStrategy.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\Path.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\PathInternal.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\PathTooLongException.cs" />
@@ -426,6 +422,11 @@
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\UnmanagedMemoryAccessor.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\UnmanagedMemoryStream.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\UnmanagedMemoryStreamWrapper.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\BufferedFileStreamStrategy.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\DerivedFileStreamStrategy.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\FileStreamHelpers.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\FileStreamStrategy.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\LegacyFileStreamStrategy.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IObservable.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IObserver.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IProgress.cs" />
@@ -1635,17 +1636,17 @@
  <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\GlobalizationMode.Windows.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\HijriCalendar.Win32.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Guid.Windows.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\AsyncWindowsFileStreamStrategy.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\DisableMediaInsertionPrompt.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\DriveInfoInternal.Windows.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStreamHelpers.Windows.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStreamCompletionSource.Win32.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\LegacyFileStreamStrategy.Windows.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\Path.Windows.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\PathHelper.Windows.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\PathInternal.Windows.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\SyncWindowsFileStreamStrategy.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\WindowsFileStreamStrategy.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\AsyncWindowsFileStreamStrategy.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\FileStreamHelpers.Windows.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\FileStreamCompletionSource.Win32.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\LegacyFileStreamStrategy.Windows.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\SyncWindowsFileStreamStrategy.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\WindowsFileStreamStrategy.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\PasteArguments.Windows.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\Loader\LibraryNameVariation.Windows.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\MemoryFailPoint.Windows.cs" />
@@ -1846,13 +1847,13 @@
  <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\GlobalizationMode.LoadICU.iOS.cs" Condition="'$(IsiOSLike)' == 'true'" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\HijriCalendar.Unix.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Guid.Unix.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStreamHelpers.Unix.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\Path.Unix.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\PathInternal.Unix.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\IO\PersistedFiles.Names.Unix.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\LegacyFileStreamStrategy.Unix.cs" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\LegacyFileStreamStrategy.Lock.OSX.cs" Condition="'$(IsOSXLike)' == 'true'" />
- <Compile Include="$(MSBuildThisFileDirectory)System\IO\LegacyFileStreamStrategy.Lock.Unix.cs" Condition="'$(IsOSXLike)' != 'true'" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\FileStreamHelpers.Unix.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\LegacyFileStreamStrategy.Unix.cs" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\LegacyFileStreamStrategy.Lock.OSX.cs" Condition="'$(IsOSXLike)' == 'true'" />
+ <Compile Include="$(MSBuildThisFileDirectory)System\IO\Strategies\LegacyFileStreamStrategy.Lock.Unix.cs" Condition="'$(IsOSXLike)' != 'true'" />
  <Compile Include="$(MSBuildThisFileDirectory)System\PasteArguments.Unix.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\Loader\LibraryNameVariation.Unix.cs" />
  <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\MemoryFailPoint.Unix.cs" />

src/libraries/System.Private.CoreLib/src/System/IO/FileStream.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.IO.Strategies;
 using System.Runtime.Serialization;
 using System.Runtime.Versioning;
 using System.Threading;
@@ -46,7 +47,7 @@ public FileStream(IntPtr handle, FileAccess access, bool ownsHandle, int bufferS
  {
  ValidateHandle(safeHandle, access, bufferSize, isAsync);
 
- _strategy = WrapIfDerivedType(FileStreamHelpers.ChooseStrategy(safeHandle, access, bufferSize, isAsync));
+ _strategy = FileStreamHelpers.ChooseStrategy(this, safeHandle, access, bufferSize, isAsync);
  }
  catch
  {
@@ -78,9 +79,6 @@ private static void ValidateHandle(SafeFileHandle handle, FileAccess access, int
  throw new ArgumentException(SR.Arg_HandleNotAsync, nameof(handle));
  }
 
- private FileStreamStrategy WrapIfDerivedType(FileStreamStrategy impl)
- => GetType() == typeof(FileStream) ? impl : new DerivedFileStreamStrategy(this, impl);
-
  public FileStream(SafeFileHandle handle, FileAccess access)
  : this(handle, access, DefaultBufferSize)
  {
@@ -95,7 +93,7 @@ public FileStream(SafeFileHandle handle, FileAccess access, int bufferSize, bool
  {
  ValidateHandle(handle, access, bufferSize, isAsync);
 
- _strategy = WrapIfDerivedType(FileStreamHelpers.ChooseStrategy(handle, access, bufferSize, isAsync));
+ _strategy = FileStreamHelpers.ChooseStrategy(this, handle, access, bufferSize, isAsync);
  }
 
  public FileStream(string path, FileMode mode) :
@@ -164,7 +162,7 @@ public FileStream(string path, FileMode mode, FileAccess access, FileShare share
  SerializationInfo.ThrowIfDeserializationInProgress("AllowFileWrites", ref s_cachedSerializationSwitch);
  }
 
- _strategy = WrapIfDerivedType(FileStreamHelpers.ChooseStrategy(path, mode, access, share, bufferSize, options));
+ _strategy = FileStreamHelpers.ChooseStrategy(this, path, mode, access, share, bufferSize, options);
  }
 
  [Obsolete("This property has been deprecated. Please use FileStream's SafeFileHandle property instead. https://go.microsoft.com/fwlink/?linkid=14202")]
@@ -479,21 +477,5 @@ internal IAsyncResult BaseBeginWrite(byte[] buffer, int offset, int count, Async
  => base.BeginWrite(buffer, offset, count, callback, state);
 
  internal void BaseEndWrite(IAsyncResult asyncResult) => base.EndWrite(asyncResult);
-
- internal static bool IsIoRelatedException(Exception e) =>
- // These all derive from IOException
- // DirectoryNotFoundException
- // DriveNotFoundException
- // EndOfStreamException
- // FileLoadException
- // FileNotFoundException
- // PathTooLongException
- // PipeException
- e is IOException ||
- // Note that SecurityException is only thrown on runtimes that support CAS
- // e is SecurityException ||
- e is UnauthorizedAccessException ||
- e is NotSupportedException ||
- (e is ArgumentException && !(e is ArgumentNullException));
  }
 }

src/libraries/System.Private.CoreLib/src/System/IO/AsyncWindowsFileStreamStrategy.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/AsyncWindowsFileStreamStrategy.cs

@@ -6,7 +6,7 @@
 using System.Threading.Tasks;
 using Microsoft.Win32.SafeHandles;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  internal sealed partial class AsyncWindowsFileStreamStrategy : WindowsFileStreamStrategy, IFileStreamCompletionSourceStrategy
  {
@@ -397,7 +397,7 @@ await FileStreamHelpers
  finally
  {
  // Make sure the stream's current position reflects where we ended up
- if (!_fileHandle.IsClosed && CanSeek)
+ if (!_fileHandle.IsClosed && canSeek)
  {
  SeekCore(_fileHandle, 0, SeekOrigin.End);
  }

src/libraries/System.Private.CoreLib/src/System/IO/BufferedFileStreamStrategy.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/BufferedFileStreamStrategy.cs

@@ -6,7 +6,7 @@
 using System.Threading.Tasks;
 using Microsoft.Win32.SafeHandles;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  // this type exists so we can avoid duplicating the buffering logic in every FileStreamStrategy implementation
  internal sealed class BufferedFileStreamStrategy : FileStreamStrategy
@@ -37,7 +37,7 @@ internal BufferedFileStreamStrategy(FileStreamStrategy strategy, int bufferSize)
  // so we enforce it by passing always true
  Dispose(true);
  }
- catch (Exception e) when (FileStream.IsIoRelatedException(e))
+ catch (Exception e) when (FileStreamHelpers.IsIoRelatedException(e))
  {
  // On finalization, ignore failures from trying to flush the write buffer,
  // e.g. if this stream is wrapping a pipe and the pipe is now broken.
@@ -74,7 +74,7 @@ public override long Position
  {
  Debug.Assert(!(_writePos > 0 && _readPos != _readLen), "Read and Write buffers cannot both have data in them at the same time.");
 
- return _strategy.Position + (_readPos - _readLen + _writePos);
+ return _strategy.Position + _readPos - _readLen + _writePos;
  }
  set
  {
@@ -598,7 +598,7 @@ private void WriteByteSlow(byte value)
  ClearReadBufferBeforeWrite();
  EnsureBufferAllocated();
  }
- else if (_writePos >= _bufferSize - 1)
+ else if (_writePos == _bufferSize - 1)
  {
  FlushWrite();
  }
@@ -1055,7 +1055,7 @@ private void EnsureCanWrite()
 
  private void EnsureBufferAllocated()
  {
- Debug.Assert(_bufferSize > 0);
+ Debug.Assert(_bufferSize > 1);
 
  // BufferedFileStreamStrategy is not intended for multi-threaded use, so no worries about the get/set race on _buffer.
  if (_buffer == null)

src/libraries/System.Private.CoreLib/src/System/IO/DerivedFileStreamStrategy.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/DerivedFileStreamStrategy.cs

@@ -5,7 +5,7 @@
 using System.Threading.Tasks;
 using Microsoft.Win32.SafeHandles;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  // this type exists so we can avoid GetType() != typeof(FileStream) checks in FileStream
  // when FileStream was supposed to call base.Method() for such cases, we just call _fileStream.BaseMethod()

src/libraries/System.Private.CoreLib/src/System/IO/FileStreamCompletionSource.Win32.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/FileStreamCompletionSource.Win32.cs

@@ -8,7 +8,7 @@
 using System.Threading.Tasks;
 using Microsoft.Win32.SafeHandles;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  // to avoid code duplicaiton of FileStreamCompletionSource for LegacyFileStreamStrategy and AsyncWindowsFileStreamStrategy
  // we have created the following interface that is a common contract for both of them

src/libraries/System.Private.CoreLib/src/System/IO/FileStreamHelpers.Unix.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/FileStreamHelpers.Unix.cs

@@ -8,16 +8,16 @@
 using System.Threading;
 using System.Threading.Tasks;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  // this type defines a set of stateless FileStream/FileStreamStrategy helper methods
- internal static class FileStreamHelpers
+ internal static partial class FileStreamHelpers
  {
  // in the future we are most probably going to introduce more strategies (io_uring etc)
- internal static FileStreamStrategy ChooseStrategy(SafeFileHandle handle, FileAccess access, int bufferSize, bool isAsync)
+ private static FileStreamStrategy ChooseStrategy(SafeFileHandle handle, FileAccess access, int bufferSize, bool isAsync)
  => new LegacyFileStreamStrategy(handle, access, bufferSize, isAsync);
 
- internal static FileStreamStrategy ChooseStrategy(string path, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options)
+ private static FileStreamStrategy ChooseStrategy(string path, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options)
  => new LegacyFileStreamStrategy(path, mode, access, share, bufferSize, options);
 
  internal static SafeFileHandle OpenHandle(string path, FileMode mode, FileAccess access, FileShare share, FileOptions options)

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

@@ -9,21 +9,17 @@
 using System.Threading.Tasks;
 using Microsoft.Win32.SafeHandles;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  // this type defines a set of stateless FileStream/FileStreamStrategy helper methods
- internal static class FileStreamHelpers
+ internal static partial class FileStreamHelpers
  {
  internal const int ERROR_BROKEN_PIPE = 109;
  internal const int ERROR_NO_DATA = 232;
  private const int ERROR_HANDLE_EOF = 38;
  private const int ERROR_IO_PENDING = 997;
 
- // It's enabled by default. We are going to change that (by removing !) once we fix #16354, #25905 and #24847.
- internal static bool UseLegacyStrategy { get; }
- = !AppContextConfigHelper.GetBooleanConfig("System.IO.UseLegacyFileStream", "DOTNET_SYSTEM_IO_USELEGACYFILESTREAM");
-
- internal static FileStreamStrategy ChooseStrategy(SafeFileHandle handle, FileAccess access, int bufferSize, bool isAsync)
+ private static FileStreamStrategy ChooseStrategy(SafeFileHandle handle, FileAccess access, int bufferSize, bool isAsync)
  {
  if (UseLegacyStrategy)
  {
@@ -37,7 +33,7 @@ internal static FileStreamStrategy ChooseStrategy(SafeFileHandle handle, FileAcc
  return EnableBufferingIfNeeded(strategy, bufferSize);
  }
 
- internal static FileStreamStrategy ChooseStrategy(string path, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options)
+ private static FileStreamStrategy ChooseStrategy(string path, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options)
  {
  if (UseLegacyStrategy)
  {

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

@@ -0,0 +1,53 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Microsoft.Win32.SafeHandles;
+
+namespace System.IO.Strategies
+{
+ internal static partial class FileStreamHelpers
+ {
+ // It's enabled by default. We are going to change that once we fix #16354, #25905 and #24847.
+ internal static bool UseLegacyStrategy { get; } = GetLegacyFileStreamSetting();
+
+ private static bool GetLegacyFileStreamSetting()
+ {
+ if (AppContext.TryGetSwitch("System.IO.UseNet5CompatFileStream", out bool fileConfig))
+ {
+ return fileConfig;
+ }
+
+ string? envVar = Environment.GetEnvironmentVariable("DOTNET_SYSTEM_IO_USENET5COMPATFILESTREAM");
+ return envVar is null
+ ? true // legacy is currently enabled by default;
+ : bool.IsTrueStringIgnoreCase(envVar) || envVar.Equals("1");
+ }
+
+ internal static FileStreamStrategy ChooseStrategy(FileStream fileStream, SafeFileHandle handle, FileAccess access, int bufferSize, bool isAsync)
+ => WrapIfDerivedType(fileStream, ChooseStrategy(handle, access, bufferSize, isAsync));
+
+ internal static FileStreamStrategy ChooseStrategy(FileStream fileStream, string path, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options)
+ => WrapIfDerivedType(fileStream, ChooseStrategy(path, mode, access, share, bufferSize, options));
+
+ private static FileStreamStrategy WrapIfDerivedType(FileStream fileStream, FileStreamStrategy strategy)
+ => fileStream.GetType() == typeof(FileStream)
+ ? strategy
+ : new DerivedFileStreamStrategy(fileStream, strategy);
+
+ internal static bool IsIoRelatedException(Exception e) =>
+ // These all derive from IOException
+ // DirectoryNotFoundException
+ // DriveNotFoundException
+ // EndOfStreamException
+ // FileLoadException
+ // FileNotFoundException
+ // PathTooLongException
+ // PipeException
+ e is IOException ||
+ // Note that SecurityException is only thrown on runtimes that support CAS
+ // e is SecurityException ||
+ e is UnauthorizedAccessException ||
+ e is NotSupportedException ||
+ (e is ArgumentException && !(e is ArgumentNullException));
+ }
+}

src/libraries/System.Private.CoreLib/src/System/IO/FileStreamStrategy.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/FileStreamStrategy.cs

@@ -3,7 +3,7 @@
 
 using Microsoft.Win32.SafeHandles;
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  internal abstract class FileStreamStrategy : Stream
  {

src/libraries/System.Private.CoreLib/src/System/IO/LegacyFileStreamStrategy.Lock.OSX.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/LegacyFileStreamStrategy.Lock.OSX.cs

@@ -1,7 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  internal sealed partial class LegacyFileStreamStrategy : FileStreamStrategy
  {

src/libraries/System.Private.CoreLib/src/System/IO/LegacyFileStreamStrategy.Lock.Unix.cs → src/libraries/System.Private.CoreLib/src/System/IO/Strategies/LegacyFileStreamStrategy.Lock.Unix.cs

@@ -1,7 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-namespace System.IO
+namespace System.IO.Strategies
 {
  internal sealed partial class LegacyFileStreamStrategy : FileStreamStrategy
  {