Use native version for LZMA.

2025-12-16 19:24:25 +00:00 · 2021-11-04 18:32:33 +00:00
parent 3125fccace
commit 0a2d78fadb
2 changed files with 102 additions and 0 deletions
--- a/Aaru.Compression/LZMA.cs
+++ b/Aaru.Compression/LZMA.cs
@@ -0,0 +1,100 @@
+// /***************************************************************************
+// Aaru Data Preservation Suite
+// ----------------------------------------------------------------------------
+//
+// Filename       : LZMA.cs
+// Author(s)      : Natalia Portillo <claunia@claunia.com>
+//
+// Component      : Compression algorithms.
+//
+// --[ 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 © 2011-2021 Natalia Portillo
+// ****************************************************************************/
+
+using System.IO;
+using System.Runtime.InteropServices;
+using SharpCompress.Compressors.LZMA;
+
+namespace Aaru.Compression;
+
+public class LZMA
+{
+    [DllImport("libAaru.Compression.Native", SetLastError = true)]
+    static extern int AARU_lzma_decode_buffer(byte[] dst_buffer, ref nuint dst_size, byte[] src_buffer,
+                                              ref nuint src_size, byte[] props, nuint propsSize);
+
+    [DllImport("libAaru.Compression.Native", SetLastError = true)]
+    static extern int AARU_lzma_encode_buffer(byte[] dst_buffer, ref nuint dst_size, byte[] src_buffer, nuint src_size,
+                                              byte[] outProps, ref nuint outPropsSize, int level, uint dictSize, int lc,
+                                              int lp, int pb, int fb, int numThreads);
+
+    /// <summary>Decodes a buffer compressed with LZMA</summary>
+    /// <param name="source">Encoded buffer</param>
+    /// <param name="destination">Buffer where to write the decoded data</param>
+    /// <returns>The number of decoded bytes</returns>
+    public static int DecodeBuffer(byte[] source, byte[] destination, byte[] properties)
+    {
+        if(Native.IsSupported)
+        {
+            var srcSize = (nuint)source.Length;
+            var dstSize = (nuint)destination.Length;
+
+            AARU_lzma_decode_buffer(destination, ref dstSize, source, ref srcSize, properties,
+                                    (nuint)properties.Length);
+
+            return (int)dstSize;
+        }
+
+        using var cmpMs     = new MemoryStream(source);
+        using var lzmaBlock = new LzmaStream(properties, cmpMs);
+        lzmaBlock.Read(destination, 0, destination.Length);
+
+        return destination.Length;
+    }
+
+    /// <summary>Compresses a buffer using BZIP2</summary>
+    /// <param name="source">Data to compress</param>
+    /// <param name="destination">Buffer to store the compressed data</param>
+    /// <returns></returns>
+    public static int EncodeBuffer(byte[] source, byte[] destination, out byte[] properties, int level, uint dictSize,
+                                   int lc, int lp, int pb, int fb)
+    {
+        if(Native.IsSupported)
+        {
+            properties = new byte[5];
+            var dstSize   = (nuint)destination.Length;
+            var propsSize = (nuint)properties.Length;
+            var srcSize   = (nuint)source.Length;
+
+            AARU_lzma_encode_buffer(destination, ref dstSize, source, srcSize, properties, ref propsSize, level,
+                                    dictSize, lc, lp, pb, fb, 0);
+
+            return (int)dstSize;
+        }
+
+        var _lzmaEncoderProperties = new LzmaEncoderProperties(true, (int)dictSize, fb);
+
+        using var lzmaStream = new LzmaStream(_lzmaEncoderProperties, false, new MemoryStream(destination));
+
+        lzmaStream.Write(source, 0, source.Length);
+        properties = new byte[lzmaStream.Properties.Length];
+        lzmaStream.Properties.CopyTo(properties, 0);
+
+        return destination.Length;
+    }
+}