context: // Unzip class for .NET 3.5 Client Profile or Mono 2.10
  // Written by Alexey Yakovlev <yallie@yandex.ru>
  // https://github.com/yallie/unzip
  
  using System;
  using System.Collections.Generic;
  using System.ComponentModel;
  using System.IO;
  using System.IO.Compression;
  using System.Linq;
  using System.Text;
  
  namespace Updater.Internals
  {
  	/// <summary>
  	/// Unzip helper class.
  	/// </summary>
  	internal class Unzip : IDisposable
  	{
  		/// <summary>
  		/// Zip archive entry.
  		/// </summary>
  		public class Entry
  		{
  			/// <summary>
  			/// Gets or sets the name of a file or a directory.
  			/// </summary>
  			public string Name { get; set; }
  
  			/// <summary>
  			/// Gets or sets the comment.
  			/// </summary>
  			public string Comment { get; set; }
  
  			/// <summary>
  			/// Gets or sets the CRC32.
  			/// </summary>
  			public uint Crc32 { get; set; }
  
  			/// <summary>
  			/// Gets or sets the compressed size of the file.
  			/// </summary>
  			public int CompressedSize { get; set; }
  
  			/// <summary>
  			/// Gets or sets the original size of the file.
  			/// </summary>
  			public int OriginalSize { get; set; }
  
  			/// <summary>
  			/// Gets or sets a value indicating whether this <see cref="Entry" /> is deflated.
  			/// </summary>
  			public bool Deflated { get; set; }
  
  			/// <summary>
  			/// Gets a value indicating whether this <see cref="Entry" /> is a directory.
  			/// </summary>
  			public bool IsDirectory { get { return Name.EndsWith("/"); } }
  
  			/// <summary>
  			/// Gets or sets the timestamp.
  			/// </summary>
  			public DateTime Timestamp { get; set; }
  
  			/// <summary>
  			/// Gets a value indicating whether this <see cref="Entry" /> is a file.
  			/// </summary>
  			public bool IsFile { get { return !IsDirectory; } }
  
  			[EditorBrowsable(EditorBrowsableState.Never)]
  			public int HeaderOffset { get; set; }
  
  			[EditorBrowsable(EditorBrowsableState.Never)]
  			public int DataOffset { get; set; }
  		}
  
  		/// <summary>
  		/// CRC32 calculation helper.
  		/// </summary>
  		public class Crc32Calculator
  		{
  			private static readonly uint[] Crc32Table =
  			{
  				0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
  				0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
  				0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
  				0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
  				0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
  				0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
  				0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
  				0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
  				0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
  				0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
  				0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
  				0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
  				0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
  				0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
  				0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
  				0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
  				0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
  				0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
  				0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
  				0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
  				0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
  				0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
  				0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
  				0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
  				0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
  				0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
  				0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
  				0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
  				0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
  				0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
  				0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
  				0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
  			};
  
  			private uint crcValue = 0xffffffff;
  
  			public uint Crc32 { get { return crcValue ^ 0xffffffff; } }
  
  			public void UpdateWithBlock(byte[] buffer, int numberOfBytes)
  			{
  				for (var i = 0; i < numberOfBytes; i++)
  				{
  					crcValue = (crcValue >> 8) ^ Crc32Table[buffer[i] ^ crcValue & 0xff];
  				}
  			}
  		}
  
  		/// <summary>
  		/// Provides data for the ExtractProgress event.
  		/// </summary>
  		public class FileProgressEventArgs : ProgressChangedEventArgs
  		{
  			/// <summary>
  			/// Initializes a new instance of the <see cref="FileProgressEventArgs"/> class.
  			/// </summary>
  			/// <param name="currentFile">The current file.</param>
  			/// <param name="totalFiles">The total files.</param>
  			/// <param name="fileName">Name of the file.</param>
  			public FileProgressEventArgs(int currentFile, int totalFiles, string fileName)
  				: base(totalFiles != 0 ? currentFile * 100 / totalFiles : 100, fileName)
  			{
  				CurrentFile = currentFile;
  				TotalFiles = totalFiles;
  				FileName = fileName;
  			}
  
  			/// <summary>
  			/// Gets the current file.
  			/// </summary>
  			public int CurrentFile { get; private set; }
  
  			/// <summary>
  			/// Gets the total files.
  			/// </summary>
  			public int TotalFiles { get; private set; }
  
  			/// <summary>
  			/// Gets the name of the file.
  			/// </summary>
  			public string FileName { get; private set; }
  		}
  
  		private const int EntrySignature = 0x02014B50;
  		private const int FileSignature = 0x04034b50;
  		private const int DirectorySignature = 0x06054B50;
  		private const int BufferSize = 16 * 1024;
  
  		/// <summary>
  		/// Occurs when a file or a directory is extracted from an archive.
  		/// </summary>
  		public event EventHandler<FileProgressEventArgs> ExtractProgress;
  
  		/// <summary>
  		/// Initializes a new instance of the <see cref="Unzip" /> class.
  		/// </summary>
  		/// <param name="fileName">Name of the file.</param>
  		public Unzip(string fileName)
  			: this(File.OpenRead(fileName))
  		{
  		}
  
  		/// <summary>
  		/// Initializes a new instance of the <see cref="Unzip" /> class.
  		/// </summary>
  		/// <param name="stream">The stream.</param>
  		public Unzip(Stream stream)
  		{
  			Stream = stream;
  			Reader = new BinaryReader(Stream);
  		}
  
  		private Stream Stream { get; set; }
  
  		private BinaryReader Reader { get; set; }
  
  		/// <summary>
  		/// Performs application-defined tasks associated with
  		/// freeing, releasing, or resetting unmanaged resources.
  		/// </summary>
  		public void Dispose()
  		{
  			if (Stream != null)
  			{
  				Stream.Dispose();
  				Stream = null;
  			}
  
  			if (Reader != null)
  			{
  				Reader.Close();
  				Reader = null;
  			}
  		}
  
  		/// <summary>
  		/// Extracts the contents of the zip file to the given directory.
  		/// </summary>
  		/// <param name="directoryName">Name of the directory.</param>
  		public void ExtractToDirectory(string directoryName)
  		{
  
gt: 			for (int index = 0; index < Entries.Length; index++)