From ad4355c2c20afb3cd2e9c3f04d5fd6ee21229bd2 Mon Sep 17 00:00:00 2001
From: Natalia Portillo <claunia@claunia.com>
Date: Sat, 9 Apr 2022 18:58:03 +0100
Subject: [PATCH] Fix managed FLAC block compression.

---
 Aaru.Compression/Aaru.Compression.csproj | 49 +++++++--------
 Aaru.Compression/FLAC.cs                 | 19 +++---
 Aaru.Compression/NonClosableStream.cs    | 78 ++++++++++++++++++++++++
 3 files changed, 112 insertions(+), 34 deletions(-)
 create mode 100644 Aaru.Compression/NonClosableStream.cs

diff --git a/Aaru.Compression/Aaru.Compression.csproj b/Aaru.Compression/Aaru.Compression.csproj
index 585b33232..9e45f4bdf 100644
--- a/Aaru.Compression/Aaru.Compression.csproj
+++ b/Aaru.Compression/Aaru.Compression.csproj
@@ -64,24 +64,25 @@
         </DefaultItemExcludes>
     </PropertyGroup>
     <ItemGroup>
-        <Compile Include="ADC.cs"/>
-        <Compile Include="AppleRle.cs"/>
-        <Compile Include="BZip2.cs"/>
-        <Compile Include="FLAC.cs"/>
-        <Compile Include="LZFSE.cs"/>
-        <Compile Include="LZIP.cs"/>
-        <Compile Include="LZMA.cs"/>
-        <Compile Include="Native.cs"/>
-        <Compile Include="TeleDiskLzh.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs/CommandLine/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs/CRC/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs/NULL/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs/ViewModel/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs/WAV/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs.Flake/*.cs"/>
-        <Compile Include="cuetools.net/CUETools.Codecs.Flake/Properties/*.cs"/>
-        <Compile Include="ZSTD.cs"/>
+        <Compile Include="ADC.cs" />
+        <Compile Include="AppleRle.cs" />
+        <Compile Include="BZip2.cs" />
+        <Compile Include="FLAC.cs" />
+        <Compile Include="LZFSE.cs" />
+        <Compile Include="LZIP.cs" />
+        <Compile Include="LZMA.cs" />
+        <Compile Include="Native.cs" />
+        <Compile Include="NonClosableStream.cs" />
+        <Compile Include="TeleDiskLzh.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs/CommandLine/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs/CRC/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs/NULL/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs/ViewModel/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs/WAV/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs.Flake/*.cs" />
+        <Compile Include="cuetools.net/CUETools.Codecs.Flake/Properties/*.cs" />
+        <Compile Include="ZSTD.cs" />
     </ItemGroup>
     <ItemGroup>
         <Content Include="..\LICENSE.LGPL">
@@ -89,12 +90,12 @@
         </Content>
     </ItemGroup>
     <ItemGroup>
-        <PackageReference Include="Aaru.Compression.Native" Version="6.0.0-alpha8"/>
-        <PackageReference Include="DotNetZip" Version="1.16.0"/>
-        <PackageReference Include="Newtonsoft.Json" Version="13.0.1"/>
-        <PackageReference Include="SharpCompress" Version="0.30.1"/>
-        <PackageReference Include="System.Resources.Extensions" Version="6.0.0"/>
-        <PackageReference Include="Unclassified.NetRevisionTask" Version="0.4.2" PrivateAssets="all"/>
+        <PackageReference Include="Aaru.Compression.Native" Version="6.0.0-alpha8" />
+        <PackageReference Include="DotNetZip" Version="1.16.0" />
+        <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
+        <PackageReference Include="SharpCompress" Version="0.30.1" />
+        <PackageReference Include="System.Resources.Extensions" Version="6.0.0" />
+        <PackageReference Include="Unclassified.NetRevisionTask" Version="0.4.2" PrivateAssets="all" />
     </ItemGroup>
     <!-- To modify your build process, add your task inside one of the targets below and uncomment it.
            Other similar extension points exist, see Microsoft.Common.targets.
diff --git a/Aaru.Compression/FLAC.cs b/Aaru.Compression/FLAC.cs
index 85dc7b4b1..295cd54e4 100644
--- a/Aaru.Compression/FLAC.cs
+++ b/Aaru.Compression/FLAC.cs
@@ -34,9 +34,7 @@ using CUETools.Codecs;
 using CUETools.Codecs.Flake;
 
 // ReSharper disable once InconsistentNaming
-/// <summary>
-/// Implements the FLAC lossless audio compression algorithm
-/// </summary>
+/// <summary>Implements the FLAC lossless audio compression algorithm</summary>
 public class FLAC
 {
     /// <summary>Set to <c>true</c> if this algorithm is supported, <c>false</c> otherwise.</summary>
@@ -49,10 +47,9 @@ public class FLAC
     [DllImport("libAaru.Compression.Native", SetLastError = true)]
     static extern nuint AARU_flac_encode_redbook_buffer(byte[] dstBuffer, nuint dstSize, byte[] srcBuffer,
                                                         nuint srcSize, uint blocksize, int doMidSideStereo,
-                                                        int looseMidSideStereo, string apodization,
-                                                        uint maxLpcOrder, uint qlpCoeffPrecision,
-                                                        int doQlpCoeffPrecSearch, int doExhaustiveModelSearch,
-                                                        uint minResidualPartitionOrder,
+                                                        int looseMidSideStereo, string apodization, uint maxLpcOrder,
+                                                        uint qlpCoeffPrecision, int doQlpCoeffPrecSearch,
+                                                        int doExhaustiveModelSearch, uint minResidualPartitionOrder,
                                                         uint maxResidualPartitionOrder, string applicationID,
                                                         uint applicationIDLen);
 
@@ -135,13 +132,15 @@ public class FLAC
         if(flakeWriterSettings.BlockSize < 256)
             flakeWriterSettings.BlockSize = 256;
 
-        var flacMs      = new MemoryStream(destination);
+        var flacMs      = new NonClosableStream(destination);
         var flakeWriter = new AudioEncoder(flakeWriterSettings, "", flacMs);
         var audioBuffer = new AudioBuffer(AudioPCMConfig.RedBook, source, source.Length / 4);
         flakeWriter.Write(audioBuffer);
         flakeWriter.Close();
-        flacMs.Close();
 
-        return (int)flacMs.Length;
+        var len = (int)flacMs.Length;
+        flacMs.ReallyClose();
+
+        return len;
     }
 }
\ No newline at end of file
diff --git a/Aaru.Compression/NonClosableStream.cs b/Aaru.Compression/NonClosableStream.cs
new file mode 100644
index 000000000..c99626c4d
--- /dev/null
+++ b/Aaru.Compression/NonClosableStream.cs
@@ -0,0 +1,78 @@
+// /***************************************************************************
+// Aaru Data Preservation Suite
+// ----------------------------------------------------------------------------
+//
+// Filename       : NonClosableStream.cs
+// Author(s)      : Natalia Portillo <claunia@claunia.com>
+//
+// Component      : Compression.
+//
+// --[ Description ] ----------------------------------------------------------
+//
+//     Overrides MemoryStream to ignore standard close requests.
+//
+// --[ License ] --------------------------------------------------------------
+//
+//     This library is free software; you can redistribute it and/or modify
+//     it under the terms of the GNU Lesser General Public License as
+//     published by the Free Software Foundation; either version 2.1 of the
+//     License, or (at your option) any later version.
+//
+//     This library is distributed in the hope that it will be useful, but
+//     WITHOUT ANY WARRANTY; without even the implied warranty of
+//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+//     Lesser General Public License for more details.
+//
+//     You should have received a copy of the GNU Lesser General Public
+//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
+//
+// ----------------------------------------------------------------------------
+// Copyright © 2011-2022 Natalia Portillo
+// ****************************************************************************/
+
+namespace Aaru.Compression;
+
+using System.IO;
+
+/// <inheritdoc />
+/// <summary>Creates a MemoryStream that ignores close commands</summary>
+sealed class NonClosableStream : Stream
+{
+    readonly MemoryStream _baseStream;
+
+    internal NonClosableStream(byte[] buffer) => _baseStream = new MemoryStream(buffer);
+
+    internal NonClosableStream() => _baseStream = new MemoryStream();
+
+    public override bool CanRead  => _baseStream.CanRead;
+    public override bool CanSeek  => _baseStream.CanSeek;
+    public override bool CanWrite => _baseStream.CanWrite;
+    public override long Length   => _baseStream.Length;
+
+    public override long Position
+    {
+        get => _baseStream.Position;
+        set => _baseStream.Position = value;
+    }
+
+    public override void Flush() => _baseStream.Flush();
+
+    public override int Read(byte[] buffer, int offset, int count) => _baseStream.Read(buffer, offset, count);
+
+    public override long Seek(long offset, SeekOrigin origin) => _baseStream.Seek(offset, origin);
+
+    public override void SetLength(long value) => _baseStream.SetLength(value);
+
+    public override void Write(byte[] buffer, int offset, int count) => _baseStream.Write(buffer, offset, count);
+
+    public override void Close()
+    {
+        // Do nothing
+    }
+
+    internal byte[] GetBuffer() => _baseStream.GetBuffer();
+
+    internal byte[] ToArray() => _baseStream.ToArray();
+
+    internal void ReallyClose() => _baseStream.Close();
+}
\ No newline at end of file