Merge pull request dotnet#1 from shutdown256/shutdown256-issue-37802

fix CopyToAsyncCore - cancellation and infinite loop
filipnavara · May 21, 2019 · e40fcb6 · e40fcb6
2 parents 0f22cd0 + 360e535
commit e40fcb6
Showing 1 changed file with 7 additions and 2 deletions.
diff --git a/src/System.IO.Pipelines/src/System/IO/Pipelines/PipeReader.cs b/src/System.IO.Pipelines/src/System/IO/Pipelines/PipeReader.cs
@@ -113,9 +113,9 @@ private async Task CopyToAsyncCore(Stream destination, CancellationToken cancell
             {
                 SequencePosition consumed = default;
 
+                ReadResult result = await ReadAsync(cancellationToken).ConfigureAwait(false);
                 try
                 {
-                    ReadResult result = await ReadAsync(cancellationToken).ConfigureAwait(false);
                     ReadOnlySequence<byte> buffer = result.Buffer;
                     SequencePosition position = buffer.Start;
 
@@ -130,7 +130,12 @@ private async Task CopyToAsyncCore(Stream destination, CancellationToken cancell
 
                         consumed = position;
                     }
-
+
+                    if (consumed.Equals(default(SequencePosition)) 
+                    {
+                        consumed = buffer.End;
+                    }
+
                     if (result.IsCompleted)
                     {
                         break;