From 13ab89379c75a574579073fc398e87ee515d484f Mon Sep 17 00:00:00 2001
From: Jeremy Powell <jeremy@visionaid.com>
Date: Tue, 8 Oct 2024 22:20:43 +1300
Subject: [PATCH 1/2] Fix StreamView Position property

Setting the position past the length is expected to increase the length
of the stream.
---
 sources/OpenMcdf/StreamView.cs | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/sources/OpenMcdf/StreamView.cs b/sources/OpenMcdf/StreamView.cs
index f7f5f54..ca31b91 100644
--- a/sources/OpenMcdf/StreamView.cs
+++ b/sources/OpenMcdf/StreamView.cs
@@ -63,18 +63,8 @@ public override void Flush()
 
         public override long Position
         {
-            get
-            {
-                return position;
-            }
-
-            set
-            {
-                if (position > length - 1)
-                    throw new ArgumentOutOfRangeException(nameof(value));
-
-                position = value;
-            }
+            get => position;
+            set => Seek(value, SeekOrigin.Begin);
         }
 
         public override int Read(byte[] buffer, int offset, int count)
@@ -185,9 +175,12 @@ public override long Seek(long offset, SeekOrigin origin)
                         throw new IOException("Seek before origin");
                     position = Length - offset;
                     break;
+
+                default:
+                    throw new ArgumentException(nameof(origin), "Invalid seek origin");
             }
 
-            if (length <= position) // Don't adjust the length when position is inside the bounds of 0 and the current length.
+            if (position > length)
                 AdjustLength(position);
 
             return position;

From 73125173cdaa45c1bba2152d7b0672bd68320861 Mon Sep 17 00:00:00 2001
From: Jeremy Powell <jeremy@visionaid.com>
Date: Wed, 9 Oct 2024 11:17:56 +1300
Subject: [PATCH 2/2] Fix StreamDecorator Seek behavior

---
 .../OpenMcdf.Extensions/StreamDecorator.cs    | 26 ++++++++++++-------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/sources/OpenMcdf.Extensions/StreamDecorator.cs b/sources/OpenMcdf.Extensions/StreamDecorator.cs
index ee3b04a..4335d7f 100644
--- a/sources/OpenMcdf.Extensions/StreamDecorator.cs
+++ b/sources/OpenMcdf.Extensions/StreamDecorator.cs
@@ -41,14 +41,8 @@ public override void Flush()
         /// <inheritdoc/>
         public override long Position
         {
-            get
-            {
-                return position;
-            }
-            set
-            {
-                position = value;
-            }
+            get => position;
+            set => Seek(value, SeekOrigin.Begin);
         }
 
         /// <inheritdoc/>
@@ -77,18 +71,30 @@ public override long Seek(long offset, SeekOrigin origin)
             switch (origin)
             {
                 case SeekOrigin.Begin:
+                    if (offset < 0)
+                        throw new IOException("Seek before origin");
                     position = offset;
                     break;
+
                 case SeekOrigin.Current:
+                    if (position + offset < 0)
+                        throw new IOException("Seek before origin");
                     position += offset;
                     break;
+
                 case SeekOrigin.End:
-                    position -= offset;
+                    if (Length - offset < 0)
+                        throw new IOException("Seek before origin");
+                    position = Length - offset;
                     break;
+
                 default:
-                    throw new Exception("Invalid origin selected");
+                    throw new ArgumentException(nameof(origin), "Invalid seek origin");
             }
 
+            if (position > Length)
+                SetLength(position);
+
             return position;
         }