public override int Read()

in src/ICSharpCode.SharpZipLib/Tar/TarInputStream.cs [229:305]
62 lines of code
10 McCabe index (conditional complexity)

		public override int Read(byte[] buffer, int offset, int count)
		{
			if (buffer == null)
			{
				throw new ArgumentNullException(nameof(buffer));
			}

			int totalRead = 0;

			if (entryOffset >= entrySize)
			{
				return 0;
			}

			long numToRead = count;

			if ((numToRead + entryOffset) > entrySize)
			{
				numToRead = entrySize - entryOffset;
			}

			if (readBuffer != null)
			{
				int sz = (numToRead > readBuffer.Length) ? readBuffer.Length : (int)numToRead;

				Array.Copy(readBuffer, 0, buffer, offset, sz);

				if (sz >= readBuffer.Length)
				{
					readBuffer = null;
				}
				else
				{
					int newLen = readBuffer.Length - sz;
					byte[] newBuf = new byte[newLen];
					Array.Copy(readBuffer, sz, newBuf, 0, newLen);
					readBuffer = newBuf;
				}

				totalRead += sz;
				numToRead -= sz;
				offset += sz;
			}

			while (numToRead > 0)
			{
				byte[] rec = tarBuffer.ReadBlock();
				if (rec == null)
				{
					// Unexpected EOF!
					throw new TarException("unexpected EOF with " + numToRead + " bytes unread");
				}

				var sz = (int)numToRead;
				int recLen = rec.Length;

				if (recLen > sz)
				{
					Array.Copy(rec, 0, buffer, offset, sz);
					readBuffer = new byte[recLen - sz];
					Array.Copy(rec, sz, readBuffer, 0, recLen - sz);
				}
				else
				{
					sz = recLen;
					Array.Copy(rec, 0, buffer, offset, recLen);
				}

				totalRead += sz;
				numToRead -= sz;
				offset += sz;
			}

			entryOffset += totalRead;

			return totalRead;
		}