cannam@128: //
cannam@128: // © Copyright Henrik Ravn 2004
cannam@128: //
cannam@128: // Use, modification and distribution are subject to the Boost Software License, Version 1.0.
cannam@128: // (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
cannam@128: //
cannam@128: 
cannam@128: using System;
cannam@128: using System.IO;
cannam@128: using System.Runtime.InteropServices;
cannam@128: using System.Text;
cannam@128: 
cannam@128: 
cannam@128: namespace DotZLib
cannam@128: {
cannam@128: 
cannam@128:     #region Internal types
cannam@128: 
cannam@128:     /// <summary>
cannam@128:     /// Defines constants for the various flush types used with zlib
cannam@128:     /// </summary>
cannam@128:     internal enum FlushTypes
cannam@128:     {
cannam@128:         None,  Partial,  Sync,  Full,  Finish,  Block
cannam@128:     }
cannam@128: 
cannam@128:     #region ZStream structure
cannam@128:     // internal mapping of the zlib zstream structure for marshalling
cannam@128:     [StructLayoutAttribute(LayoutKind.Sequential, Pack=4, Size=0, CharSet=CharSet.Ansi)]
cannam@128:     internal struct ZStream
cannam@128:     {
cannam@128:         public IntPtr next_in;
cannam@128:         public uint avail_in;
cannam@128:         public uint total_in;
cannam@128: 
cannam@128:         public IntPtr next_out;
cannam@128:         public uint avail_out;
cannam@128:         public uint total_out;
cannam@128: 
cannam@128:         [MarshalAs(UnmanagedType.LPStr)]
cannam@128:         string msg;
cannam@128:         uint state;
cannam@128: 
cannam@128:         uint zalloc;
cannam@128:         uint zfree;
cannam@128:         uint opaque;
cannam@128: 
cannam@128:         int data_type;
cannam@128:         public uint adler;
cannam@128:         uint reserved;
cannam@128:     }
cannam@128: 
cannam@128:     #endregion
cannam@128: 
cannam@128:     #endregion
cannam@128: 
cannam@128:     #region Public enums
cannam@128:     /// <summary>
cannam@128:     /// Defines constants for the available compression levels in zlib
cannam@128:     /// </summary>
cannam@128:     public enum CompressLevel : int
cannam@128:     {
cannam@128:         /// <summary>
cannam@128:         /// The default compression level with a reasonable compromise between compression and speed
cannam@128:         /// </summary>
cannam@128:         Default = -1,
cannam@128:         /// <summary>
cannam@128:         /// No compression at all. The data are passed straight through.
cannam@128:         /// </summary>
cannam@128:         None = 0,
cannam@128:         /// <summary>
cannam@128:         /// The maximum compression rate available.
cannam@128:         /// </summary>
cannam@128:         Best = 9,
cannam@128:         /// <summary>
cannam@128:         /// The fastest available compression level.
cannam@128:         /// </summary>
cannam@128:         Fastest = 1
cannam@128:     }
cannam@128:     #endregion
cannam@128: 
cannam@128:     #region Exception classes
cannam@128:     /// <summary>
cannam@128:     /// The exception that is thrown when an error occurs on the zlib dll
cannam@128:     /// </summary>
cannam@128:     public class ZLibException : ApplicationException
cannam@128:     {
cannam@128:         /// <summary>
cannam@128:         /// Initializes a new instance of the <see cref="ZLibException"/> class with a specified
cannam@128:         /// error message and error code
cannam@128:         /// </summary>
cannam@128:         /// <param name="errorCode">The zlib error code that caused the exception</param>
cannam@128:         /// <param name="msg">A message that (hopefully) describes the error</param>
cannam@128:         public ZLibException(int errorCode, string msg) : base(String.Format("ZLib error {0} {1}", errorCode, msg))
cannam@128:         {
cannam@128:         }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Initializes a new instance of the <see cref="ZLibException"/> class with a specified
cannam@128:         /// error code
cannam@128:         /// </summary>
cannam@128:         /// <param name="errorCode">The zlib error code that caused the exception</param>
cannam@128:         public ZLibException(int errorCode) : base(String.Format("ZLib error {0}", errorCode))
cannam@128:         {
cannam@128:         }
cannam@128:     }
cannam@128:     #endregion
cannam@128: 
cannam@128:     #region Interfaces
cannam@128: 
cannam@128:     /// <summary>
cannam@128:     /// Declares methods and properties that enables a running checksum to be calculated
cannam@128:     /// </summary>
cannam@128:     public interface ChecksumGenerator
cannam@128:     {
cannam@128:         /// <summary>
cannam@128:         /// Gets the current value of the checksum
cannam@128:         /// </summary>
cannam@128:         uint Value { get; }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Clears the current checksum to 0
cannam@128:         /// </summary>
cannam@128:         void Reset();
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Updates the current checksum with an array of bytes
cannam@128:         /// </summary>
cannam@128:         /// <param name="data">The data to update the checksum with</param>
cannam@128:         void Update(byte[] data);
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Updates the current checksum with part of an array of bytes
cannam@128:         /// </summary>
cannam@128:         /// <param name="data">The data to update the checksum with</param>
cannam@128:         /// <param name="offset">Where in <c>data</c> to start updating</param>
cannam@128:         /// <param name="count">The number of bytes from <c>data</c> to use</param>
cannam@128:         /// <exception cref="ArgumentException">The sum of offset and count is larger than the length of <c>data</c></exception>
cannam@128:         /// <exception cref="ArgumentNullException"><c>data</c> is a null reference</exception>
cannam@128:         /// <exception cref="ArgumentOutOfRangeException">Offset or count is negative.</exception>
cannam@128:         void Update(byte[] data, int offset, int count);
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Updates the current checksum with the data from a string
cannam@128:         /// </summary>
cannam@128:         /// <param name="data">The string to update the checksum with</param>
cannam@128:         /// <remarks>The characters in the string are converted by the UTF-8 encoding</remarks>
cannam@128:         void Update(string data);
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Updates the current checksum with the data from a string, using a specific encoding
cannam@128:         /// </summary>
cannam@128:         /// <param name="data">The string to update the checksum with</param>
cannam@128:         /// <param name="encoding">The encoding to use</param>
cannam@128:         void Update(string data, Encoding encoding);
cannam@128:     }
cannam@128: 
cannam@128: 
cannam@128:     /// <summary>
cannam@128:     /// Represents the method that will be called from a codec when new data
cannam@128:     /// are available.
cannam@128:     /// </summary>
cannam@128:     /// <paramref name="data">The byte array containing the processed data</paramref>
cannam@128:     /// <paramref name="startIndex">The index of the first processed byte in <c>data</c></paramref>
cannam@128:     /// <paramref name="count">The number of processed bytes available</paramref>
cannam@128:     /// <remarks>On return from this method, the data may be overwritten, so grab it while you can.
cannam@128:     /// You cannot assume that startIndex will be zero.
cannam@128:     /// </remarks>
cannam@128:     public delegate void DataAvailableHandler(byte[] data, int startIndex, int count);
cannam@128: 
cannam@128:     /// <summary>
cannam@128:     /// Declares methods and events for implementing compressors/decompressors
cannam@128:     /// </summary>
cannam@128:     public interface Codec
cannam@128:     {
cannam@128:         /// <summary>
cannam@128:         /// Occurs when more processed data are available.
cannam@128:         /// </summary>
cannam@128:         event DataAvailableHandler DataAvailable;
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Adds more data to the codec to be processed.
cannam@128:         /// </summary>
cannam@128:         /// <param name="data">Byte array containing the data to be added to the codec</param>
cannam@128:         /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>
cannam@128:         void Add(byte[] data);
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Adds more data to the codec to be processed.
cannam@128:         /// </summary>
cannam@128:         /// <param name="data">Byte array containing the data to be added to the codec</param>
cannam@128:         /// <param name="offset">The index of the first byte to add from <c>data</c></param>
cannam@128:         /// <param name="count">The number of bytes to add</param>
cannam@128:         /// <remarks>Adding data may, or may not, raise the <c>DataAvailable</c> event</remarks>
cannam@128:         void Add(byte[] data, int offset, int count);
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Finishes up any pending data that needs to be processed and handled.
cannam@128:         /// </summary>
cannam@128:         void Finish();
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Gets the checksum of the data that has been added so far
cannam@128:         /// </summary>
cannam@128:         uint Checksum { get; }
cannam@128: 
cannam@128: 
cannam@128:     }
cannam@128: 
cannam@128:     #endregion
cannam@128: 
cannam@128:     #region Classes
cannam@128:     /// <summary>
cannam@128:     /// Encapsulates general information about the ZLib library
cannam@128:     /// </summary>
cannam@128:     public class Info
cannam@128:     {
cannam@128:         #region DLL imports
cannam@128:         [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
cannam@128:         private static extern uint zlibCompileFlags();
cannam@128: 
cannam@128:         [DllImport("ZLIB1.dll", CallingConvention=CallingConvention.Cdecl)]
cannam@128:         private static extern string zlibVersion();
cannam@128:         #endregion
cannam@128: 
cannam@128:         #region Private stuff
cannam@128:         private uint _flags;
cannam@128: 
cannam@128:         // helper function that unpacks a bitsize mask
cannam@128:         private static int bitSize(uint bits)
cannam@128:         {
cannam@128:             switch (bits)
cannam@128:             {
cannam@128:                 case 0: return 16;
cannam@128:                 case 1: return 32;
cannam@128:                 case 2: return 64;
cannam@128:             }
cannam@128:             return -1;
cannam@128:         }
cannam@128:         #endregion
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Constructs an instance of the <c>Info</c> class.
cannam@128:         /// </summary>
cannam@128:         public Info()
cannam@128:         {
cannam@128:             _flags = zlibCompileFlags();
cannam@128:         }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// True if the library is compiled with debug info
cannam@128:         /// </summary>
cannam@128:         public bool HasDebugInfo { get { return 0 != (_flags & 0x100); } }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// True if the library is compiled with assembly optimizations
cannam@128:         /// </summary>
cannam@128:         public bool UsesAssemblyCode { get { return 0 != (_flags & 0x200); } }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Gets the size of the unsigned int that was compiled into Zlib
cannam@128:         /// </summary>
cannam@128:         public int SizeOfUInt { get { return bitSize(_flags & 3); } }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Gets the size of the unsigned long that was compiled into Zlib
cannam@128:         /// </summary>
cannam@128:         public int SizeOfULong { get { return bitSize((_flags >> 2) & 3); } }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Gets the size of the pointers that were compiled into Zlib
cannam@128:         /// </summary>
cannam@128:         public int SizeOfPointer { get { return bitSize((_flags >> 4) & 3); } }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Gets the size of the z_off_t type that was compiled into Zlib
cannam@128:         /// </summary>
cannam@128:         public int SizeOfOffset { get { return bitSize((_flags >> 6) & 3); } }
cannam@128: 
cannam@128:         /// <summary>
cannam@128:         /// Gets the version of ZLib as a string, e.g. "1.2.1"
cannam@128:         /// </summary>
cannam@128:         public static string Version { get { return zlibVersion(); } }
cannam@128:     }
cannam@128: 
cannam@128:     #endregion
cannam@128: 
cannam@128: }