50 lines
1.7 KiB
C#
50 lines
1.7 KiB
C#
using System;
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using System.IO;
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using SevenZip.Compression.LZMA;
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namespace UnityFS
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{
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public static class ComparessHelper
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{
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public static MemoryStream Decompress7Zip(MemoryStream inStream)
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{
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var decoder = new Decoder();
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inStream.Seek(0, SeekOrigin.Begin);
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var newOutStream = new MemoryStream();
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var properties = new byte[5];
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if (inStream.Read(properties, 0, 5) != 5)
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throw new Exception("input .lzma is too short");
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long outSize = 0;
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for (var i = 0; i < 8; i++)
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{
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var v = inStream.ReadByte();
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if (v < 0)
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throw new Exception("Can't Read 1");
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outSize |= ((long)(byte)v) << (8 * i);
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}
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decoder.SetDecoderProperties(properties);
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var compressedSize = inStream.Length - inStream.Position;
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decoder.Code(inStream, newOutStream, compressedSize, outSize, null);
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newOutStream.Position = 0;
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return newOutStream;
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}
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public static void Decompress7Zip(Stream compressedStream, Stream decompressedStream, long compressedSize, long decompressedSize)
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{
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var basePosition = compressedStream.Position;
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var decoder = new Decoder();
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var properties = new byte[5];
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if (compressedStream.Read(properties, 0, 5) != 5)
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throw new Exception("input .lzma is too short");
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decoder.SetDecoderProperties(properties);
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decoder.Code(compressedStream, decompressedStream, compressedSize - 5, decompressedSize, null);
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compressedStream.Position = basePosition + compressedSize;
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}
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}
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}
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