Fix a few more things.

1 files changed, 12 insertions, 6 deletions

diff --git a/Duplicati/Library/Utility/ReadLimitLengthStream.cs b/Duplicati/Library/Utility/ReadLimitLengthStream.cs
index 06ac06907..a6fd8e1d1 100644
--- a/Duplicati/Library/Utility/ReadLimitLengthStream.cs
+++ b/Duplicati/Library/Utility/ReadLimitLengthStream.cs
@@ -10,7 +10,10 @@ namespace Duplicati.Library.Utility
 

     /// <summary>

     /// This class wraps a Stream but only allows reading a limited number of bytes from the underlying stream.

-    /// This can be used to create split a source stream into multiple smaller buffers that can be used as independent streams.

+    /// This can be used to create a stream that exposes only a small window of a source stream.

+    /// Having multiple copies of this wrapper on the same base stream at the same time is not ideal

+    /// (as the position will move around), but creating multiple of these streams one after another

+    /// can be used to create a sliding window over a base stream.

     /// </summary>
     public class ReadLimitLengthStream : Stream
     {
@@ -25,6 +28,10 @@ namespace Duplicati.Library.Utility
 

         public ReadLimitLengthStream(Stream innerStream, long start, long length)
         {
+            if (innerStream == null)

+            {

+                throw new ArgumentNullException(nameof(innerStream))

+            }
             if (start < 0 || start > innerStream.Length)
             {
                 throw new ArgumentOutOfRangeException(nameof(start));
@@ -34,7 +41,7 @@ namespace Duplicati.Library.Utility
                 throw new ArgumentOutOfRangeException(nameof(length));
             }
 
-            m_innerStream = innerStream ?? throw new ArgumentNullException(nameof(innerStream));
+            m_innerStream = innerStream;
             m_start = start;

             m_length = length;

 

@@ -93,17 +100,16 @@ namespace Duplicati.Library.Utility
 
         public override long Seek(long offset, SeekOrigin origin)
         {

-            long innerPosition;

             switch (origin)

             {

                 case SeekOrigin.Begin:

-                    innerPosition = m_innerStream.Seek(m_start + offset, SeekOrigin.Begin);

+                    m_innerStream.Seek(m_start + offset, SeekOrigin.Begin);

                     break;

                 case SeekOrigin.Current:

-                    innerPosition = m_innerStream.Seek(offset, SeekOrigin.Current);

+                    m_innerStream.Seek(offset, SeekOrigin.Current);

                     break;

                 case SeekOrigin.End:

-                    innerPosition = m_innerStream.Seek(m_start + m_length + offset, SeekOrigin.Begin);

+                    m_innerStream.Seek(m_start + m_length + offset, SeekOrigin.Begin);

                     break;

                 default:

                     throw new ArgumentException("Unknown SeekOrigin", nameof(origin));