Merge pull request #2343 from justinvp/filesysteminfo

Eliminate extra IFileSystemObject allocation for FileSystemInfo/FileInfo/DirectoryInfo on Win32 and Unix

Author: stephentoub

src/Common/src/Interop/Windows/mincore/Interop.GetFileAttributesEx.cs

@@ -30,7 +30,7 @@ internal struct WIN32_FILE_ATTRIBUTE_DATA
             internal uint fileSizeHigh;
             internal uint fileSizeLow;
 
-            internal void PopulateFrom(WIN32_FIND_DATA findData)
+            internal void PopulateFrom(ref WIN32_FIND_DATA findData)
             {
                 // Copy the information to data
                 fileAttributes = (int)findData.dwFileAttributes;

src/System.IO.FileSystem/src/System.IO.FileSystem.csproj

@@ -57,13 +57,15 @@
   <ItemGroup Condition="'$(TargetsWindows)' == 'true'">
     <Compile Include="Microsoft\Win32\SafeHandles\SafeFileHandle.Windows.cs" />
     <Compile Include="Microsoft\Win32\SafeHandles\SafeFindHandle.Windows.cs" />
+    <Compile Include="System\IO\DirectoryInfo.Windows.cs" />
+    <Compile Include="System\IO\FileInfo.Windows.cs" />
     <Compile Include="System\IO\FileStream.Win32.cs" />
+    <Compile Include="System\IO\FileSystemInfo.Windows.cs" />
     <Compile Include="System\IO\PathHelpers.Windows.cs" />
     <Compile Include="System\IO\Win32FileStream.cs" />
     <Compile Include="System\IO\Win32FileStreamCompletionSource.cs" />
     <Compile Include="System\IO\Win32FileSystem.cs" />
     <Compile Include="System\IO\Win32FileSystemEnumerable.cs" />
-    <Compile Include="System\IO\Win32FileSystemObject.cs" />
     <Compile Include="$(CommonPath)\Interop\Windows\Interop.Libraries.cs">
       <Link>Common\Interop\Windows\Interop.Libraries.cs</Link>
     </Compile>
@@ -191,6 +193,7 @@
       <Link>Common\Interop\Windows\Interop.CopyFile.cs</Link>
     </Compile>
     <Compile Include="System\IO\FileSystem.Current.Win32.cs" />
+    <Compile Include="System\IO\FileSystemInfo.Win32.cs" />
     <Compile Include="$(CommonPath)\Interop\Windows\mincore\Interop.CreateFile.cs">
       <Link>Common\Interop\Windows\Interop.CreateFile.cs</Link>
     </Compile>
@@ -219,6 +222,7 @@
       <Link>Common\Interop\Windows\WinRT\Interop.SetErrorMode.cs</Link>
     </Compile>
     <Compile Include="System\IO\FileSystem.Current.MuxWin32WinRT.cs" />
+    <Compile Include="System\IO\FileSystemInfo.WinRT.cs" />
     <Compile Include="System\IO\MultiplexingWin32WinRTFileSystem.cs" />
     <Compile Include="System\IO\WinRTIOExtensions.cs" />
     <Compile Include="System\IO\WinRTFileStream.cs" />
@@ -236,10 +240,10 @@
     <Compile Include="Microsoft\Win32\SafeHandles\SafeFileHandle.Unix.cs" />
     <Compile Include="System\IO\FileStream.Unix.cs" />
     <Compile Include="System\IO\FileSystem.Current.Unix.cs" />
+    <Compile Include="System\IO\FileSystemInfo.Unix.cs" />
     <Compile Include="System\IO\PathHelpers.Unix.cs" />
     <Compile Include="System\IO\UnixFileStream.cs" />
     <Compile Include="System\IO\UnixFileSystem.cs" />
-    <Compile Include="System\IO\UnixFileSystemObject.cs" />
     <Compile Include="$(CommonPath)\Microsoft\Win32\SafeHandles\SafeFileHandle.Unix.cs">
       <Link>Common\Microsoft\Win32\SafeHandles\SafeFileHandle.Unix.cs</Link>
     </Compile>

src/System.IO.FileSystem/src/System/IO/DirectoryInfo.Windows.cs

@@ -0,0 +1,19 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Diagnostics;
+using System.Security;
+
+namespace System.IO
+{
+    partial class DirectoryInfo
+    {
+        [SecurityCritical]
+        internal DirectoryInfo(string fullPath, ref Interop.mincore.WIN32_FIND_DATA findData)
+            : this(fullPath, findData.cFileName)
+        {
+            Debug.Assert(string.Equals(findData.cFileName, Path.GetFileName(fullPath), StringComparison.Ordinal));
+            Init(ref findData);
+        }
+    }
+}

src/System.IO.FileSystem/src/System/IO/DirectoryInfo.cs

@@ -8,7 +8,7 @@
 
 namespace System.IO
 {
-    public sealed class DirectoryInfo : FileSystemInfo
+    public sealed partial class DirectoryInfo : FileSystemInfo
     {
         [System.Security.SecuritySafeCritical]
         public DirectoryInfo(String path)
@@ -23,12 +23,12 @@ public DirectoryInfo(String path)
         }
 
         [System.Security.SecuritySafeCritical]
-        internal DirectoryInfo(String fullPath, IFileSystemObject fileSystemObject) : base(fileSystemObject)
+        internal DirectoryInfo(String fullPath, String originalPath)
         {
-            Debug.Assert(PathInternal.GetRootLength(fullPath) > 0, "fullPath must be fully qualified!");
-            
+            Debug.Assert(Path.IsPathRooted(fullPath), "fullPath must be fully qualified!");
+
             // Fast path when we know a DirectoryInfo exists.
-            OriginalPath = Path.GetFileName(fullPath);
+            OriginalPath = originalPath ?? Path.GetFileName(fullPath);
             FullPath = fullPath;
             DisplayPath = GetDisplayName(OriginalPath, FullPath);
         }

src/System.IO.FileSystem/src/System/IO/FileInfo.Windows.cs

@@ -0,0 +1,19 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Diagnostics;
+using System.Security;
+
+namespace System.IO
+{
+    partial class FileInfo
+    {
+        [SecurityCritical]
+        internal FileInfo(string fullPath, ref Interop.mincore.WIN32_FIND_DATA findData)
+            : this(fullPath, findData.cFileName)
+        {
+            Debug.Assert(string.Equals(findData.cFileName, Path.GetFileName(fullPath), StringComparison.Ordinal));
+            Init(ref findData);
+        }
+    }
+}

src/System.IO.FileSystem/src/System/IO/FileInfo.cs

@@ -13,7 +13,7 @@ namespace System.IO
 {
     // Class for creating FileStream objects, and some basic file management
     // routines such as Delete, etc.
-    public sealed class FileInfo : FileSystemInfo
+    public sealed partial class FileInfo : FileSystemInfo
     {
         private String _name;
 
@@ -48,10 +48,10 @@ private String GetDisplayPath(String originalPath)
         }
 
         [System.Security.SecuritySafeCritical]
-        internal FileInfo(String fullPath, IFileSystemObject fileSystemObject) : base(fileSystemObject)
+        internal FileInfo(String fullPath, String originalPath)
         {
             Debug.Assert(Path.IsPathRooted(fullPath), "fullPath must be fully qualified!");
-            _name = Path.GetFileName(fullPath);
+            _name = originalPath ?? Path.GetFileName(fullPath);
             OriginalPath = _name;
             FullPath = fullPath;
             DisplayPath = _name;