Imported Upstream version 1.0.0.9127upstream/1.0.0.9127

1 files changed, 76 insertions, 0 deletions

diff --git a/src/mscorlib/corefx/System/IO/FileStream.NetStandard17.cs b/src/mscorlib/corefx/System/IO/FileStream.NetStandard17.cs
new file mode 100644
index 0000000000..dc1385fbc0
--- /dev/null
+++ b/src/mscorlib/corefx/System/IO/FileStream.NetStandard17.cs
@@ -0,0 +1,76 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using Microsoft.Win32.SafeHandles;
+using System.Threading.Tasks;
+using System.Diagnostics;
+using System.Threading;
+
+namespace System.IO
+{
+    public partial class FileStream : Stream
+    {
+        public override IAsyncResult BeginRead(byte[] array, int offset, int numBytes, AsyncCallback callback, object state)
+        {
+            if (array == null)
+                throw new ArgumentNullException(nameof(array));
+            if (offset < 0)
+                throw new ArgumentOutOfRangeException(nameof(offset), SR.ArgumentOutOfRange_NeedNonNegNum);
+            if (numBytes < 0)
+                throw new ArgumentOutOfRangeException(nameof(numBytes), SR.ArgumentOutOfRange_NeedNonNegNum);
+            if (array.Length - offset < numBytes)
+                throw new ArgumentException(SR.Argument_InvalidOffLen);
+
+            if (IsClosed) throw new ObjectDisposedException(SR.ObjectDisposed_FileClosed);
+            if (!CanRead) throw new NotSupportedException(SR.NotSupported_UnreadableStream);
+
+            if (!IsAsync)
+                return base.BeginRead(array, offset, numBytes, callback, state);
+            else
+                return TaskToApm.Begin(ReadAsyncInternal(array, offset, numBytes, CancellationToken.None), callback, state);
+        }
+
+        public override IAsyncResult BeginWrite(byte[] array, int offset, int numBytes, AsyncCallback callback, object state)
+        {
+            if (array == null)
+                throw new ArgumentNullException(nameof(array));
+            if (offset < 0)
+                throw new ArgumentOutOfRangeException(nameof(offset), SR.ArgumentOutOfRange_NeedNonNegNum);
+            if (numBytes < 0)
+                throw new ArgumentOutOfRangeException(nameof(numBytes), SR.ArgumentOutOfRange_NeedNonNegNum);
+            if (array.Length - offset < numBytes)
+                throw new ArgumentException(SR.Argument_InvalidOffLen);
+
+            if (IsClosed) throw new ObjectDisposedException(SR.ObjectDisposed_FileClosed);
+            if (!CanWrite) throw new NotSupportedException(SR.NotSupported_UnwritableStream);
+
+            if (!IsAsync)
+                return base.BeginWrite(array, offset, numBytes, callback, state);
+            else
+                return TaskToApm.Begin(WriteAsyncInternal(array, offset, numBytes, CancellationToken.None), callback, state);
+        }
+
+        public override int EndRead(IAsyncResult asyncResult)
+        {
+            if (asyncResult == null)
+                throw new ArgumentNullException(nameof(asyncResult));
+
+            if (!IsAsync)
+                return base.EndRead(asyncResult);
+            else
+                return TaskToApm.End<int>(asyncResult);
+        }
+
+        public override void EndWrite(IAsyncResult asyncResult)
+        {
+            if (asyncResult == null)
+                throw new ArgumentNullException(nameof(asyncResult));
+
+            if (!IsAsync)
+                base.EndWrite(asyncResult);
+            else
+                TaskToApm.End(asyncResult);
+        }
+    }
+}