ICSharpCode.SharpZipLib.Zip.Compression.DeflaterHuffman.TallyDist C# (CSharp) Method

        public bool TallyDist(int distance, int length)
        {
            //			if (DeflaterConstants.DEBUGGING) {
            //				//Console.WriteLine("[" + distance + "," + length + "]");
            //			}

            d_buf[last_lit] = (short)distance;
            l_buf[last_lit++] = (byte)(length - 3);

            int lc = Lcode(length - 3);
            literalTree.freqs[lc]++;
            if (lc >= 265 && lc < 285) {
                extra_bits += (lc - 261) / 4;
            }

            int dc = Dcode(distance - 1);
            distTree.freqs[dc]++;
            if (dc >= 4) {
                extra_bits += dc / 2 - 1;
            }
            return IsFull();
        }

        bool DeflateFast(bool flush, bool finish)
        {
            if (lookahead < MIN_LOOKAHEAD && !flush)
            {
                return(false);
            }

            while (lookahead >= MIN_LOOKAHEAD || flush)
            {
                if (lookahead == 0)
                {
                    // We are flushing everything
                    huffman.FlushBlock(window, blockStart, strstart - blockStart, finish);
                    blockStart = strstart;
                    return(false);
                }

                if (strstart > 2 * WSIZE - MIN_LOOKAHEAD)
                {
                    /* slide window, as FindLongestMatch needs this.
                     * This should only happen when flushing and the window
                     * is almost full.
                     */
                    SlideWindow();
                }

                int hashHead;
                if (lookahead >= MIN_MATCH &&
                    (hashHead = InsertString()) != 0 &&
                    strategy != DeflateStrategy.HuffmanOnly &&
                    strstart - hashHead <= MAX_DIST &&
                    FindLongestMatch(hashHead))
                {
                    // longestMatch sets matchStart and matchLen
            #if DebugDeflation
                    if (DeflaterConstants.DEBUGGING)
                    {
                        for (int i = 0; i < matchLen; i++)
                        {
                            if (window[strstart + i] != window[matchStart + i])
                            {
                                throw new SharpZipBaseException("Match failure");
                            }
                        }
                    }
            #endif

                    bool full = huffman.TallyDist(strstart - matchStart, matchLen);

                    lookahead -= matchLen;
                    if (matchLen <= max_lazy && lookahead >= MIN_MATCH)
                    {
                        while (--matchLen > 0)
                        {
                            ++strstart;
                            InsertString();
                        }
                        ++strstart;
                    }
                    else
                    {
                        strstart += matchLen;
                        if (lookahead >= MIN_MATCH - 1)
                        {
                            UpdateHash();
                        }
                    }
                    matchLen = MIN_MATCH - 1;
                    if (!full)
                    {
                        continue;
                    }
                }
                else
                {
                    // No match found
                    huffman.TallyLit(window[strstart] & 0xff);
                    ++strstart;
                    --lookahead;
                }

                if (huffman.IsFull())
                {
                    bool lastBlock = finish && (lookahead == 0);
                    huffman.FlushBlock(window, blockStart, strstart - blockStart, lastBlock);
                    blockStart = strstart;
                    return(!lastBlock);
                }
            }
            return(true);
        }