1 files changed, 210 insertions, 0 deletions
diff --git a/src/mscorlib/shared/System/IO/UnmanagedMemoryStreamWrapper.cs b/src/mscorlib/shared/System/IO/UnmanagedMemoryStreamWrapper.cs
new file mode 100644
index 0000000000..d547e771d7
--- /dev/null
+++ b/src/mscorlib/shared/System/IO/UnmanagedMemoryStreamWrapper.cs
@@ -0,0 +1,210 @@
+// 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.
+
+/*============================================================
+**
+** 
+** 
+**
+** Purpose: Create a Memorystream over an UnmanagedMemoryStream
+**
+===========================================================*/
+
+using System;
+using System.Runtime.InteropServices;
+using System.Diagnostics.CodeAnalysis;
+using System.Diagnostics.Contracts;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace System.IO
+{
+    // Needed for backwards compatibility with V1.x usages of the
+    // ResourceManager, where a MemoryStream is now returned as an 
+    // UnmanagedMemoryStream from ResourceReader.
+    internal sealed class UnmanagedMemoryStreamWrapper : MemoryStream
+    {
+        private UnmanagedMemoryStream _unmanagedStream;
+
+        internal UnmanagedMemoryStreamWrapper(UnmanagedMemoryStream stream)
+        {
+            _unmanagedStream = stream;
+        }
+
+        public override bool CanRead
+        {
+            get { return _unmanagedStream.CanRead; }
+        }
+
+        public override bool CanSeek
+        {
+            get { return _unmanagedStream.CanSeek; }
+        }
+
+        public override bool CanWrite
+        {
+            get { return _unmanagedStream.CanWrite; }
+        }
+
+        protected override void Dispose(bool disposing)
+        {
+            try
+            {
+                if (disposing)
+                    _unmanagedStream.Dispose();
+            }
+            finally
+            {
+                base.Dispose(disposing);
+            }
+        }
+
+        public override void Flush()
+        {
+            _unmanagedStream.Flush();
+        }
+
+        public override byte[] GetBuffer()
+        {
+            throw new UnauthorizedAccessException(SR.UnauthorizedAccess_MemStreamBuffer);
+        }
+
+        public override bool TryGetBuffer(out ArraySegment<byte> buffer)
+        {
+            buffer = default(ArraySegment<byte>);
+            return false;
+        }
+
+        public override int Capacity
+        {
+            get
+            {
+                return (int)_unmanagedStream.Capacity;
+            }
+            [SuppressMessage("Microsoft.Contracts", "CC1055")]  // Skip extra error checking to avoid *potential* AppCompat problems.
+            set
+            {
+                throw new IOException(SR.IO_FixedCapacity);
+            }
+        }
+
+        public override long Length
+        {
+            get
+            {
+                return _unmanagedStream.Length;
+            }
+        }
+
+        public override long Position
+        {
+            get
+            {
+                return _unmanagedStream.Position;
+            }
+            set
+            {
+                _unmanagedStream.Position = value;
+            }
+        }
+
+        public override int Read(byte[] buffer, int offset, int count)
+        {
+            return _unmanagedStream.Read(buffer, offset, count);
+        }
+
+        public override int ReadByte()
+        {
+            return _unmanagedStream.ReadByte();
+        }
+
+        public override long Seek(long offset, SeekOrigin loc)
+        {
+            return _unmanagedStream.Seek(offset, loc);
+        }
+
+        public unsafe override byte[] ToArray()
+        {
+            byte[] buffer = new byte[_unmanagedStream.Length];
+            _unmanagedStream.Read(buffer, 0, (int)_unmanagedStream.Length);
+            return buffer;
+        }
+
+        public override void Write(byte[] buffer, int offset, int count)
+        {
+            _unmanagedStream.Write(buffer, offset, count);
+        }
+
+        public override void WriteByte(byte value)
+        {
+            _unmanagedStream.WriteByte(value);
+        }
+
+        // Writes this MemoryStream to another stream.
+        public unsafe override void WriteTo(Stream stream)
+        {
+            if (stream == null)
+                throw new ArgumentNullException(nameof(stream), SR.ArgumentNull_Stream);
+            Contract.EndContractBlock();
+
+            byte[] buffer = ToArray();
+
+            stream.Write(buffer, 0, buffer.Length);
+        }
+
+        public override void SetLength(Int64 value)
+        {
+            // This was probably meant to call _unmanagedStream.SetLength(value), but it was forgotten in V.4.0.
+            // Now this results in a call to the base which touches the underlying array which is never actually used.
+            // We cannot fix it due to compat now, but we should fix this at the next SxS release oportunity.
+            base.SetLength(value);
+        }
+
+
+        public override Task CopyToAsync(Stream destination, Int32 bufferSize, CancellationToken cancellationToken)
+        {
+            // The parameter checks must be in sync with the base version:
+            if (destination == null)
+                throw new ArgumentNullException(nameof(destination));
+
+            if (bufferSize <= 0)
+                throw new ArgumentOutOfRangeException(nameof(bufferSize), SR.ArgumentOutOfRange_NeedPosNum);
+
+            if (!CanRead && !CanWrite)
+                throw new ObjectDisposedException(null, SR.ObjectDisposed_StreamClosed);
+
+            if (!destination.CanRead && !destination.CanWrite)
+                throw new ObjectDisposedException(nameof(destination), SR.ObjectDisposed_StreamClosed);
+
+            if (!CanRead)
+                throw new NotSupportedException(SR.NotSupported_UnreadableStream);
+
+            if (!destination.CanWrite)
+                throw new NotSupportedException(SR.NotSupported_UnwritableStream);
+
+            Contract.EndContractBlock();
+
+            return _unmanagedStream.CopyToAsync(destination, bufferSize, cancellationToken);
+        }
+
+
+        public override Task FlushAsync(CancellationToken cancellationToken)
+        {
+            return _unmanagedStream.FlushAsync(cancellationToken);
+        }
+
+
+        public override Task<Int32> ReadAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
+        {
+            return _unmanagedStream.ReadAsync(buffer, offset, count, cancellationToken);
+        }
+
+
+        public override Task WriteAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
+        {
+            return _unmanagedStream.WriteAsync(buffer, offset, count, cancellationToken);
+        }
+    }  // class UnmanagedMemoryStreamWrapper
+}  // namespace
+