System.util.zlib.Deflate.deflateInit2 C# (CSharp) Method

        internal int deflateInit2(ZStream strm, int level, int method,  int windowBits,
            int memLevel, int strategy){
            int noheader = 0;
            //    byte[] my_version=ZLIB_VERSION;

            //
            //  if (version == null || version[0] != my_version[0]
            //  || stream_size != sizeof(z_stream)) {
            //  return Z_VERSION_ERROR;
            //  }

            strm.msg = null;

            if (level == Z_DEFAULT_COMPRESSION) level = 6;

            if (windowBits < 0) { // undocumented feature: suppress zlib header
                noheader = 1;
                windowBits = -windowBits;
            }

            if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || 
                method != Z_DEFLATED ||
                windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
                strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
                return Z_STREAM_ERROR;
            }

            strm.dstate = (Deflate)this;

            this.noheader = noheader;
            w_bits = windowBits;
            w_size = 1 << w_bits;
            w_mask = w_size - 1;

            hash_bits = memLevel + 7;
            hash_size = 1 << hash_bits;
            hash_mask = hash_size - 1;
            hash_shift = ((hash_bits+MIN_MATCH-1)/MIN_MATCH);

            window = new byte[w_size*2];
            prev = new short[w_size];
            head = new short[hash_size];

            lit_bufsize = 1 << (memLevel + 6); // 16K elements by default

            // We overlay pending_buf and d_buf+l_buf. This works since the average
            // output size for (length,distance) codes is <= 24 bits.
            pending_buf = new byte[lit_bufsize*4];
            pending_buf_size = lit_bufsize*4;

            d_buf = lit_bufsize/2;
            l_buf = (1+2)*lit_bufsize;

            this.level = level;

            //System.out.println("level="+level);

            this.strategy = strategy;
            this.method = (byte)method;

            return deflateReset(strm);
        }