Adjusts the directory until a compilation database is found.

def find_compilation_database(path):
  """Adjusts the directory until a compilation database is found."""
  result = './'
  while not os.path.isfile(os.path.join(result, path)):
    if os.path.realpath(result) == '/':
      print('Error: could not find compilation database.')
      sys.exit(1)
    result += '../'
  return os.path.realpath(result)