Exemplo n.º 1
0
        /// <summary>Calculates the Adler32 check-sum on specified portion of a buffer.</summary>
        /// <param name="data">Data buffer to perform check-sum on.</param>
        /// <param name="startIndex">Starts index in data buffer to begin check-sum.</param>
        /// <param name="length">Total number of bytes from <paramref name="startIndex">startIndex</paramref> to
        /// perform check-sum over.</param>
        /// <remarks>
        /// <para>
        /// Computes Adler32 checksum for a stream of data. An Adler32 checksum is not as reliable as a CRC32
        /// checksum, but a lot faster to compute.
        /// </para>
        /// <para>
        /// The specification for Adler32 may be found in RFC 1950. ZLIB Compressed Data Format Specification
        /// version 3.3.
        /// </para>
        /// </remarks>
        /// <returns>Computed Adler32 checksum over the specified portion of the buffer.</returns>
        public static uint Adler32Checksum(this byte[] data, int startIndex, int length)
        {
            Adler32 checksum = new Adler32();

            checksum.Update(data, startIndex, length);

            return checksum.Value;
        }
Exemplo n.º 2
0
		/// <summary>
		/// Creates a new inflater.
		/// </summary>
		/// <param name="noHeader">
		/// True if no RFC1950/Zlib header and footer fields are expected in the input data
		/// 
		/// This is used for GZIPed/Zipped input.
		/// 
		/// For compatibility with
		/// Sun JDK you should provide one byte of input more than needed in
		/// this case.
		/// </param>
		public Inflater(bool noHeader)
		{
			this.noHeader = noHeader;
			this.adler = new Adler32();
			input = new StreamManipulator();
			outputWindow = new OutputWindow();
			mode = noHeader ? DECODE_BLOCKS : DECODE_HEADER;
		}
Exemplo n.º 3
0
		/// <summary>
		/// Construct instance with pending buffer
		/// </summary>
		/// <param name="pending">
		/// Pending buffer to use
		/// </param>>
		public DeflaterEngine(DeflaterPending pending) 
		{
			this.pending = pending;
			huffman = new DeflaterHuffman(pending);
			adler = new Adler32();
			
			window = new byte[2 * WSIZE];
			head   = new short[HASH_SIZE];
			prev   = new short[WSIZE];
			
			// We start at index 1, to avoid an implementation deficiency, that
			// we cannot build a repeat pattern at index 0.
			blockStart = strstart = 1;
		}