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// 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.
using System;
using System.IO;
using System.Globalization;
using System.Diagnostics;
using MS.Internal.IO.Packaging.CompoundFile;
#if PBTCOMPILER
namespace MS.Internal.Markup
#else
namespace System.Windows.Markup
#endif
{
internal class BamlVersionHeader
{
// The current BAML record version. This is incremented whenever
// the BAML format changes
// Baml Format Breaking Changes should change this.
internal static readonly VersionPair BamlWriterVersion;
static BamlVersionHeader()
{
// Initialize the Version number this way so that it can be
// seen in the Lutz Reflector.
BamlWriterVersion = new VersionPair(0, 96);
}
public BamlVersionHeader()
{
_bamlVersion = new FormatVersion("MSBAML", BamlWriterVersion);
}
public FormatVersion BamlVersion
{
get { return _bamlVersion; }
#if !PBTCOMPILER
set { _bamlVersion = value; }
#endif
}
// This is used by Async loading to measure if the whole record is present
static public int BinarySerializationSize
{
get
{
// Unicode "MSBAML" = 12
// + 4 bytes length header = 12 + 4 = 16
// + 3*(16bit MinorVer + 16bit MajorVer) = 16+(3*(2+2))= 28
// For product stability the size of this data structure
// shouldn't change anyway.
return 28;
}
}
#if !PBTCOMPILER
internal void LoadVersion(BinaryReader bamlBinaryReader)
{
#if DEBUG
long posStart = bamlBinaryReader.BaseStream.Position;
#endif
BamlVersion = FormatVersion.LoadFromStream(bamlBinaryReader.BaseStream);
#if DEBUG
long posEnd = bamlBinaryReader.BaseStream.Position;
Debug.Assert((posEnd-posStart) == BamlVersionHeader.BinarySerializationSize,
"Incorrect Baml Version Header Size");
#endif
// We're assuming that only major versions are significant for compatibility,
// so if we have a major version in the file that is higher than that in
// the code, we can't read it.
if (BamlVersion.ReaderVersion != BamlWriterVersion)
{
throw new InvalidOperationException(SR.Format(SR.ParserBamlVersion,
(BamlVersion.ReaderVersion.Major.ToString(CultureInfo.CurrentCulture) + "." +
BamlVersion.ReaderVersion.Minor.ToString(CultureInfo.CurrentCulture)),
(BamlWriterVersion.Major.ToString(CultureInfo.CurrentCulture) + "." +
BamlWriterVersion.Minor.ToString(CultureInfo.CurrentCulture))));
}
}
#endif
internal void WriteVersion(BinaryWriter bamlBinaryWriter)
{
#if DEBUG
long posStart = bamlBinaryWriter.BaseStream.Position;
#endif
BamlVersion.SaveToStream(bamlBinaryWriter.BaseStream);
#if DEBUG
long posEnd = bamlBinaryWriter.BaseStream.Position;
if(-1 == posStart)
{
long length = bamlBinaryWriter.BaseStream.Length;
Debug.Assert(length == BamlVersionHeader.BinarySerializationSize,
"Incorrect Baml Version Header Size");
}
else
{
Debug.Assert((posEnd-posStart) == BamlVersionHeader.BinarySerializationSize,
"Incorrect Baml Version Header Size");
}
#endif
}
FormatVersion _bamlVersion;
}
}
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