code: private File getBaseDirectory()
      {
          File referenceFile = ( solutionFile != null ? solutionFile : getInputFile() );
          return referenceFile.getParentFile().getAbsoluteFile();
      }
docs: Retrieve the base directory for the Visual C++ project. If this project is part of a Visual Studio solution, the
  base directory is the solution directory; for standalone projects, the base directory is the project directory.
  @return the base directory for the Visual C++ project