diff --git a/SabreTools.Serialization/Wrappers/ViewStream.cs b/SabreTools.Serialization/Wrappers/ViewStream.cs
index fbe99363..723bd5fe 100644
--- a/SabreTools.Serialization/Wrappers/ViewStream.cs
+++ b/SabreTools.Serialization/Wrappers/ViewStream.cs
@@ -1,15 +1,25 @@
using System;
using System.IO;
-namespace SabreTools.Serialization.Wrappers
+// TODO: Remove when IO is updated
+namespace SabreTools.IO.Streams
{
///
- /// Represents the data source backing the wrapper
+ /// Stream representing a view into a source
///
public class ViewStream : Stream
{
#region Properties
+ ///
+ public override bool CanRead => true;
+
+ ///
+ public override bool CanSeek => _source.CanSeek;
+
+ ///
+ public override bool CanWrite => false;
+
///
/// Filename from the source, if possible
///
@@ -32,8 +42,33 @@ namespace SabreTools.Serialization.Wrappers
///
public override long Position
{
- get { return _source.Position - _initialPosition; }
- set { _source.Position = value + _initialPosition; }
+ get
+ {
+ // Handle 0-length sources
+ if (_length <= 0)
+ return 0;
+
+ return _source.Position - _initialPosition;
+ }
+ set
+ {
+ // Handle 0-length sources
+ if (_length <= 0)
+ {
+ _source.Position = 0;
+ return;
+ }
+
+ long position = value;
+
+ // Handle out-of-bounds seeks
+ if (position < 0)
+ position = 0;
+ else if (position >= _length)
+ position = _length - 1;
+
+ _source.Position = _initialPosition + position;
+ }
}
#endregion
@@ -64,14 +99,56 @@ namespace SabreTools.Serialization.Wrappers
#region Constructors
+ ///
+ /// Construct a new ViewStream from a Stream
+ ///
+ public ViewStream(Stream data, long offset)
+ {
+ if (!data.CanRead)
+ throw new ArgumentException(nameof(data));
+ if (offset < 0 || offset > data.Length)
+ throw new ArgumentOutOfRangeException(nameof(offset));
+
+ _source = data;
+ _initialPosition = offset;
+ _length = data.Length - offset;
+
+ _source.Seek(_initialPosition, SeekOrigin.Begin);
+ }
+
///
/// Construct a new ViewStream from a Stream
///
public ViewStream(Stream data, long offset, long length)
{
+ if (!data.CanRead)
+ throw new ArgumentException(nameof(data));
+ if (offset < 0 || offset > data.Length)
+ throw new ArgumentOutOfRangeException(nameof(offset));
+ if (length < 0 || offset + length > data.Length)
+ throw new ArgumentOutOfRangeException(nameof(length));
+
_source = data;
_initialPosition = offset;
_length = length;
+
+ _source.Seek(_initialPosition, SeekOrigin.Begin);
+ }
+
+ ///
+ /// Construct a new ViewStream from a byte array
+ ///
+ public ViewStream(byte[] data, long offset)
+ {
+ if (offset < 0 || offset > data.Length)
+ throw new ArgumentOutOfRangeException(nameof(offset));
+
+ long length = data.Length - offset;
+ _source = new MemoryStream(data, (int)offset, (int)length);
+ _initialPosition = 0;
+ _length = length;
+
+ _source.Seek(_initialPosition, SeekOrigin.Begin);
}
///
@@ -79,9 +156,16 @@ namespace SabreTools.Serialization.Wrappers
///
public ViewStream(byte[] data, long offset, long length)
{
+ if (offset < 0 || offset > data.Length)
+ throw new ArgumentOutOfRangeException(nameof(offset));
+ if (length < 0 || offset + length > data.Length)
+ throw new ArgumentOutOfRangeException(nameof(length));
+
_source = new MemoryStream(data, (int)offset, (int)length);
_initialPosition = 0;
_length = length;
+
+ _source.Seek(_initialPosition, SeekOrigin.Begin);
}
#endregion
@@ -94,13 +178,14 @@ namespace SabreTools.Serialization.Wrappers
/// Position in the source
/// Length of the data to check
/// True if the positional data is valid, false otherwise
- public bool SegmentValid(int offset, int count)
+ public bool SegmentValid(long offset, long count)
{
- // If we have an invalid position
- if (offset < 0 || offset >= Length)
+ if (offset < 0 || offset > Length)
+ return false;
+ if (count < 0 || offset + count > Length)
return false;
- return _initialPosition + offset + count <= Length;
+ return true;
}
#endregion
@@ -108,28 +193,26 @@ namespace SabreTools.Serialization.Wrappers
#region Stream Implementations
///
- public override bool CanRead => true;
-
- ///
- public override bool CanWrite => false;
-
- ///
- public override bool CanSeek => _source.CanSeek;
-
- ///
- public override void Flush() => _source.Flush();
+ public override void Flush()
+ => throw new NotImplementedException();
///
public override int Read(byte[] buffer, int offset, int count)
{
- // Validate the requested segment
- if (!SegmentValid(offset, count))
+ // Invalid cases always return 0
+ if (buffer.Length == 0)
+ return 0;
+ if (offset < 0 || offset >= buffer.Length)
+ return 0;
+ if (count < 0 || offset + count > buffer.Length)
+ return 0;
+
+ // Short-circuit 0-byte reads
+ if (count == 0)
return 0;
try
{
- // Correct the read offset
- offset += (int)_initialPosition;
lock (_sourceLock)
{
return _source.Read(buffer, offset, count);
@@ -154,18 +237,11 @@ namespace SabreTools.Serialization.Wrappers
case SeekOrigin.End: Position = _length + offset - 1; break;
default: throw new ArgumentException($"Invalid value for {nameof(origin)}");
}
- ;
-
- // Handle out-of-bounds seeks
- if (Position < 0)
- Position = 0;
- else if (Position >= _length)
- Position = _length - 1;
return Position;
}
- ///
+ ///
public override void SetLength(long value)
=> throw new NotImplementedException();
diff --git a/SabreTools.Serialization/Wrappers/WrapperBase.cs b/SabreTools.Serialization/Wrappers/WrapperBase.cs
index 23e97dec..2ab88fc9 100644
--- a/SabreTools.Serialization/Wrappers/WrapperBase.cs
+++ b/SabreTools.Serialization/Wrappers/WrapperBase.cs
@@ -3,6 +3,7 @@ using System.Collections.Generic;
using System.IO;
using System.Text;
using SabreTools.IO.Extensions;
+using SabreTools.IO.Streams;
using SabreTools.Serialization.Interfaces;
namespace SabreTools.Serialization.Wrappers