private bool DecodeHuffman()

in src/ICSharpCode.SharpZipLib/Zip/Compression/Inflater.cs [283:386]
93 lines of code
20 McCabe index (conditional complexity)

		private bool DecodeHuffman()
		{
			int free = outputWindow.GetFreeSpace();
			while (free >= 258)
			{
				int symbol;
				switch (mode)
				{
					case DECODE_HUFFMAN:
						// This is the inner loop so it is optimized a bit
						while (((symbol = litlenTree.GetSymbol(input)) & ~0xff) == 0)
						{
							outputWindow.Write(symbol);
							if (--free < 258)
							{
								return true;
							}
						}

						if (symbol < 257)
						{
							if (symbol < 0)
							{
								return false;
							}
							else
							{
								// symbol == 256: end of block
								distTree = null;
								litlenTree = null;
								mode = DECODE_BLOCKS;
								return true;
							}
						}

						try
						{
							repLength = CPLENS[symbol - 257];
							neededBits = CPLEXT[symbol - 257];
						}
						catch (Exception)
						{
							throw new SharpZipBaseException("Illegal rep length code");
						}
						goto case DECODE_HUFFMAN_LENBITS; // fall through

					case DECODE_HUFFMAN_LENBITS:
						if (neededBits > 0)
						{
							mode = DECODE_HUFFMAN_LENBITS;
							int i = input.PeekBits(neededBits);
							if (i < 0)
							{
								return false;
							}
							input.DropBits(neededBits);
							repLength += i;
						}
						mode = DECODE_HUFFMAN_DIST;
						goto case DECODE_HUFFMAN_DIST; // fall through

					case DECODE_HUFFMAN_DIST:
						symbol = distTree.GetSymbol(input);
						if (symbol < 0)
						{
							return false;
						}

						try
						{
							repDist = CPDIST[symbol];
							neededBits = CPDEXT[symbol];
						}
						catch (Exception)
						{
							throw new SharpZipBaseException("Illegal rep dist code");
						}

						goto case DECODE_HUFFMAN_DISTBITS; // fall through

					case DECODE_HUFFMAN_DISTBITS:
						if (neededBits > 0)
						{
							mode = DECODE_HUFFMAN_DISTBITS;
							int i = input.PeekBits(neededBits);
							if (i < 0)
							{
								return false;
							}
							input.DropBits(neededBits);
							repDist += i;
						}

						outputWindow.Repeat(repLength, repDist);
						free -= repLength;
						mode = DECODE_HUFFMAN;
						break;

					default:
						throw new SharpZipBaseException("Inflater unknown mode");
				}
			}
			return true;
		}