Chris@43: //
Chris@43: // © Copyright Henrik Ravn 2004
Chris@43: //
Chris@43: // Use, modification and distribution are subject to the Boost Software License, Version 1.0.
Chris@43: // (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@43: //
Chris@43: 
Chris@43: using System;
Chris@43: using System.IO;
Chris@43: using System.Runtime.InteropServices;
Chris@43: using System.Text;
Chris@43: 
Chris@43: 
Chris@43: namespace DotZLib
Chris@43: {
Chris@43: 
Chris@43:     #region Internal types
Chris@43: 
Chris@43:     /// <summary>
Chris@43:     /// Defines constants for the various flush types used with zlib
Chris@43:     /// </summary>
Chris@43:     internal enum FlushTypes
Chris@43:     {
Chris@43:         None,  Partial,  Sync,  Full,  Finish,  Block
Chris@43:     }
Chris@43: 
Chris@43:     #region ZStream structure
Chris@43:     // internal mapping of the zlib zstream structure for marshalling
Chris@43:     [StructLayoutAttribute(LayoutKind.Sequential, Pack=4, Size=0, CharSet=CharSet.Ansi)]
Chris@43:     internal struct ZStream
Chris@43:     {
Chris@43:         public IntPtr next_in;
Chris@43:         public uint avail_in;
Chris@43:         public uint total_in;
Chris@43: 
Chris@43:         public IntPtr next_out;
Chris@43:         public uint avail_out;
Chris@43:         public uint total_out;
Chris@43: 
Chris@43:         [MarshalAs(UnmanagedType.LPStr)]
Chris@43:         string msg;
Chris@43:         uint state;
Chris@43: 
Chris@43:         uint zalloc;
Chris@43:         uint zfree;
Chris@43:         uint opaque;
Chris@43: 
Chris@43:         int data_type;
Chris@43:         public uint adler;
Chris@43:         uint reserved;
Chris@43:     }
Chris@43: 
Chris@43:     #endregion
Chris@43: 
Chris@43:     #endregion
Chris@43: 
Chris@43:     #region Public enums
Chris@43:     /// <summary>
Chris@43:     /// Defines constants for the available compression levels in zlib
Chris@43:     /// </summary>
Chris@43:     public enum CompressLevel : int
Chris@43:     {
Chris@43:         /// <summary>
Chris@43:         /// The default compression level with a reasonable compromise between compression and speed
Chris@43:         /// </summary>
Chris@43:         Default = -1,
Chris@43:         /// <summary>
Chris@43:         /// No compression at all. The data are passed straight through.
Chris@43:         /// </summary>
Chris@43:         None = 0,
Chris@43:         /// <summary>
Chris@43:         /// The maximum compression rate available.
Chris@43:         /// </summary>
Chris@43:         Best = 9,
Chris@43:         /// <summary>
Chris@43:         /// The fastest available compression level.
Chris@43:         /// </summary>
Chris@43:         Fastest = 1
Chris@43:     }
Chris@43:     #endregion
Chris@43: 
Chris@43:     #region Exception classes
Chris@43:     /// <summary>
Chris@43:     /// The exception that is thrown when an error occurs on the zlib dll
Chris@43:     /// </summary>
Chris@43:     public class ZLibException : ApplicationException
Chris@43:     {
Chris@43:         /// <summary>
Chris@43:         /// Initializes a new instance of the <see cref="ZLibException"/> class with a specified
Chris@43:         /// error message and error code
Chris@43:         /// </summary>
Chris@43:         /// <param name="errorCode">The zlib error code that caused the exception</param>
Chris@43:         /// <param name="msg">A message that (hopefully) describes the error</param>
Chris@43:         public ZLibException(int errorCode, string msg) : base(String.Format("ZLib error {0} {1}", errorCode, msg))
Chris@43:         {
Chris@43:         }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Initializes a new instance of the <see cref="ZLibException"/> class with a specified
Chris@43:         /// error code
Chris@43:         /// </summary>
Chris@43:         /// <param name="errorCode">The zlib error code that caused the exception</param>
Chris@43:         public ZLibException(int errorCode) : base(String.Format("ZLib error {0}", errorCode))
Chris@43:         {
Chris@43:         }
Chris@43:     }
Chris@43:     #endregion
Chris@43: 
Chris@43:     #region Interfaces
Chris@43: 
Chris@43:     /// <summary>
Chris@43:     /// Declares methods and properties that enables a running checksum to be calculated
Chris@43:     /// </summary>
Chris@43:     public interface ChecksumGenerator
Chris@43:     {
Chris@43:         /// <summary>
Chris@43:         /// Gets the current value of the checksum
Chris@43:         /// </summary>
Chris@43:         uint Value { get; }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Clears the current checksum to 0
Chris@43:         /// </summary>
Chris@43:         void Reset();
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Updates the current checksum with an array of bytes
Chris@43:         /// </summary>
Chris@43:         /// <param name="data">The data to update the checksum with</param>
Chris@43:         void Update(byte[] data);
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Updates the current checksum with part of an array of bytes
Chris@43:         /// </summary>
Chris@43:         /// <param name="data">The data to update the checksum with</param>
Chris@43:         /// <param name="offset">Where in <c>data</c> to start updating</param>
Chris@43:         /// <param name="count">The number of bytes from <c>data</c> to use</param>
Chris@43:         /// <exception cref="ArgumentException">The sum of offset and count is larger than the length of <c>data</c></exception>
Chris@43:         /// <exception cref="ArgumentNullException"><c>data</c> is a null reference</exception>
Chris@43:         /// <exception cref="ArgumentOutOfRangeException">Offset or count is negative.</exception>
Chris@43:         void Update(byte[] data, int offset, int count);
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Updates the current checksum with the data from a string
Chris@43:         /// </summary>
Chris@43:         /// <param name="data">The string to update the checksum with</param>
Chris@43:         /// <remarks>The characters in the string are converted by the UTF-8 encoding</remarks>
Chris@43:         void Update(string data);
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Updates the current checksum with the data from a string, using a specific encoding
Chris@43:         /// </summary>
Chris@43:         /// <param name="data">The string to update the checksum with</param>
Chris@43:         /// <param name="encoding">The encoding to use</param>
Chris@43:         void Update(string data, Encoding encoding);
Chris@43:     }
Chris@43: 
Chris@43: 
Chris@43:     /// <summary>
Chris@43:     /// Represents the method that will be called from a codec when new data
Chris@43:     /// are available.
Chris@43:     /// </summary>
Chris@43:     /// <paramref name="data">The byte array containing the processed data</paramref>
Chris@43:     /// <paramref name="startIndex">The index of the first processed byte in <c>data</c></paramref>
Chris@43:     /// <paramref name="count">The number of processed bytes available</paramref>
Chris@43:     /// <remarks>On return from this method, the data may be overwritten, so grab it while you can.
Chris@43:     /// You cannot assume that startIndex will be zero.
Chris@43:     /// </remarks>
Chris@43:     public delegate void DataAvailableHandler(byte[] data, int startIndex, int count);
Chris@43: 
Chris@43:     /// <summary>
Chris@43:     /// Declares methods and events for implementing compressors/decompressors
Chris@43:     /// </summary>
Chris@43:     public interface Codec
Chris@43:     {
Chris@43:         /// <summary>
Chris@43:         /// Occurs when more processed data are available.
Chris@43:         /// </summary>
Chris@43:         event DataAvailableHandler DataAvailable;
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Adds more data to the codec to be processed.
Chris@43:         /// </summary>
Chris@43:         /// <param name="data">Byte array containing the data to be added to the codec</param>
Chris@43:         /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>
Chris@43:         void Add(byte[] data);
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Adds more data to the codec to be processed.
Chris@43:         /// </summary>
Chris@43:         /// <param name="data">Byte array containing the data to be added to the codec</param>
Chris@43:         /// <param name="offset">The index of the first byte to add from <c>data</c></param>
Chris@43:         /// <param name="count">The number of bytes to add</param>
Chris@43:         /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>
Chris@43:         void Add(byte[] data, int offset, int count);
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Finishes up any pending data that needs to be processed and handled.
Chris@43:         /// </summary>
Chris@43:         void Finish();
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Gets the checksum of the data that has been added so far
Chris@43:         /// </summary>
Chris@43:         uint Checksum { get; }
Chris@43: 
Chris@43: 
Chris@43:     }
Chris@43: 
Chris@43:     #endregion
Chris@43: 
Chris@43:     #region Classes
Chris@43:     /// <summary>
Chris@43:     /// Encapsulates general information about the ZLib library
Chris@43:     /// </summary>
Chris@43:     public class Info
Chris@43:     {
Chris@43:         #region DLL imports
Chris@43:         [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
Chris@43:         private static extern uint zlibCompileFlags();
Chris@43: 
Chris@43:         [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
Chris@43:         private static extern string zlibVersion();
Chris@43:         #endregion
Chris@43: 
Chris@43:         #region Private stuff
Chris@43:         private uint _flags;
Chris@43: 
Chris@43:         // helper function that unpacks a bitsize mask
Chris@43:         private static int bitSize(uint bits)
Chris@43:         {
Chris@43:             switch (bits)
Chris@43:             {
Chris@43:                 case 0: return 16;
Chris@43:                 case 1: return 32;
Chris@43:                 case 2: return 64;
Chris@43:             }
Chris@43:             return -1;
Chris@43:         }
Chris@43:         #endregion
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Constructs an instance of the <c>Info</c> class.
Chris@43:         /// </summary>
Chris@43:         public Info()
Chris@43:         {
Chris@43:             _flags = zlibCompileFlags();
Chris@43:         }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// True if the library is compiled with debug info
Chris@43:         /// </summary>
Chris@43:         public bool HasDebugInfo { get { return 0 != (_flags & 0x100); } }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// True if the library is compiled with assembly optimizations
Chris@43:         /// </summary>
Chris@43:         public bool UsesAssemblyCode { get { return 0 != (_flags & 0x200); } }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Gets the size of the unsigned int that was compiled into Zlib
Chris@43:         /// </summary>
Chris@43:         public int SizeOfUInt { get { return bitSize(_flags & 3); } }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Gets the size of the unsigned long that was compiled into Zlib
Chris@43:         /// </summary>
Chris@43:         public int SizeOfULong { get { return bitSize((_flags >> 2) & 3); } }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Gets the size of the pointers that were compiled into Zlib
Chris@43:         /// </summary>
Chris@43:         public int SizeOfPointer { get { return bitSize((_flags >> 4) & 3); } }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Gets the size of the z_off_t type that was compiled into Zlib
Chris@43:         /// </summary>
Chris@43:         public int SizeOfOffset { get { return bitSize((_flags >> 6) & 3); } }
Chris@43: 
Chris@43:         /// <summary>
Chris@43:         /// Gets the version of ZLib as a string, e.g. "1.2.1"
Chris@43:         /// </summary>
Chris@43:         public static string Version { get { return zlibVersion(); } }
Chris@43:     }
Chris@43: 
Chris@43:     #endregion
Chris@43: 
Chris@43: }