internal static byte[] DecompressLZMAFile(byte[] lzmaFile)
{
int len = (int)BitConverter.ToInt32(lzmaFile, 5); //this is technically a 32-bit but since MEM code can't handle 64 bit sizes we are just going to use 32bit.
if (len >= 0)
{
byte[] strippedData = new byte[lzmaFile.Length - 8];
//Non-Streamed (made from disk)
Buffer.BlockCopy(lzmaFile, 0, strippedData, 0, 5);
Buffer.BlockCopy(lzmaFile, 13, strippedData, 5, lzmaFile.Length - 13);
return(Decompress(strippedData, (uint)len));
}
else if (len == -1)
{
//Streamed. MEM code can't handle streamed so we have to fallback
var lzmads = new LzmaDecodeStream(new MemoryStream(lzmaFile));
using var decompressedStream = new MemoryStream();
int bufSize = 24576, count;
byte[] buf = new byte[bufSize];
while (/*lzmads.Position < lzmaFile.Length && */ (count = lzmads.Read(buf, 0, bufSize)) > 0)
{
decompressedStream.Write(buf, 0, count);
}
return(decompressedStream.ToArray());
}
else
{
Debug.WriteLine("Cannot decompress LZMA array: Length is not positive or -1 (" + len + ")! This is not an LZMA array");
return(null); //Not LZMA!
}
}
/// <summary>
/// Decompresses LZMA. Uses native code if non-streamed (produced by lzma.exe), uses managed code if streamed (which can be done by things such as PHP)
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public static byte[] DecompressLZMA(MemoryStream input)
{
input.Position = 5;
var lzmaLen = input.ReadInt32();
input.Position = 0;
if (lzmaLen > 0)
{
// Non streamed LZMA
return(LZMA.DecompressLZMAFile(input.ToArray()));
}
else
{
// It's streaming lzma. MEM code can't handle streamed so we have to fallback
var lzmads = new LzmaDecodeStream(input);
using var decompressedStream = new MemoryStream();
int bufSize = 24576, count;
byte[] buf = new byte[bufSize];
while (/*lzmads.Position < lzmaFile.Length && */ (count = lzmads.Read(buf, 0, bufSize)) > 0)
{
decompressedStream.Write(buf, 0, count);
}
return(decompressedStream.ToArray());
}
}
/// <summary>
/// 使用Lzma算法从字节流解压缩为集合
/// </summary>
/// <typeparam name="Data"></typeparam>
/// <param name="buffer"></param>
/// <returns></returns>
public static List <Data> Decodes <Data>(byte[] buffer) where Data : class
{
if (buffer == null || buffer.Length == 0)
{
return(null);
}
List <Data> lstData = new List <Data>();
using (var input = new MemoryStream())
{
input.Write(buffer, 0, buffer.Length);
input.Position = 0;
var decoder = new LzmaDecodeStream(input);
using (MemoryStream output = new MemoryStream())
{
int bufSize = 24576, count;
byte[] buf = new byte[bufSize];
while ((count = decoder.Read(buf, 0, bufSize)) > 0)
{
output.Write(buf, 0, count);
}
output.Position = 0;
BinaryFormatter formatter = new BinaryFormatter();
while (true)
{
if (output.Position == output.Length)
{
break;
}
Data data = null;
try
{
data = formatter.Deserialize(output) as Data;
}
catch (SerializationException ex)
{
LogHelper.GetInstance().Write("反序列化失败！");
}
if (data == null)
{
break;
}
lstData.Add(data);
}
}
decoder.Close();
}
return(lstData);
}
public void LzmaEncodeDecodeTest()
{
using (var output = new FileStream(TemporaryFile, FileMode.Create))
{
var encoder = new LzmaEncodeStream(output);
using (var inputSample = new FileStream(@"TestData\zip.zip", FileMode.Open))
{
int bufSize = 24576, count;
var buf = new byte[bufSize];
while ((count = inputSample.Read(buf, 0, bufSize)) > 0)
{
encoder.Write(buf, 0, count);
}
}
encoder.Close();
}
var newZip = Path.Combine(OutputDirectory, "new.zip");
using (var input = new FileStream(TemporaryFile, FileMode.Open))
{
var decoder = new LzmaDecodeStream(input);
using (var output = new FileStream(newZip, FileMode.Create))
{
int bufSize = 24576, count;
var buf = new byte[bufSize];
while ((count = decoder.Read(buf, 0, bufSize)) > 0)
{
output.Write(buf, 0, count);
}
}
}
Assert.IsTrue(File.Exists(newZip));
using (var extractor = new SevenZipExtractor(newZip))
{
Assert.AreEqual(1, extractor.FilesCount);
Assert.AreEqual("zip.txt", extractor.ArchiveFileNames[0]);
}
}
public bool unzipFile(string filePath, out string result)
{
FileInfo fileInfo = new FileInfo(filePath);
// Step 1. Fix file
fixFile(filePath, fileInfo);
// Step 2. Unzip file
string outputPath = fileInfo.FullName.Replace(".csv", "_r.csv");
try
{
using (var input = new FileStream(filePath, FileMode.Open, FileAccess.ReadWrite))
{
var decoder = new LzmaDecodeStream(input);
using (var output = new FileStream(outputPath, FileMode.Create))
{
int bufSize = 24576, count;
byte[] buf = new byte[bufSize];
while ((count = decoder.Read(buf, 0, bufSize)) > 0)
{
output.Write(buf, 0, count);
}
}
decoder.Close();
}
}
catch (Exception)
{
result = "[Broken file]\t" + fileInfo.Name;
File.Delete(outputPath);
return(false);
}
result = "[Unzip file]\t" + fileInfo.Name;
return(true);
}