BROKEN_ALLCONFIG_PATH = 'tools/testing/kunit/configs/broken_on_uml.config'
 OUTFILE_PATH = 'test.log'
 
+def get_file_path(build_dir, default):
+       if build_dir:
+               default = os.path.join(build_dir, default)
+       return default
+
 class ConfigError(Exception):
        """Represents an error trying to configure the Linux kernel."""
 
 
        def linux_bin(self, params, timeout, build_dir):
                """Runs the Linux UML binary. Must be named 'linux'."""
-               linux_bin = './linux'
-               if build_dir:
-                       linux_bin = os.path.join(build_dir, 'linux')
+               linux_bin = get_file_path(build_dir, 'linux')
                outfile = get_outfile_path(build_dir)
                with open(outfile, 'w') as output:
                        process = subprocess.Popen([linux_bin] + params,
                        process.wait(timeout)
 
 def get_kconfig_path(build_dir):
-       kconfig_path = KCONFIG_PATH
-       if build_dir:
-               kconfig_path = os.path.join(build_dir, KCONFIG_PATH)
-       return kconfig_path
+       return get_file_path(build_dir, KCONFIG_PATH)
 
 def get_kunitconfig_path(build_dir):
-       kunitconfig_path = KUNITCONFIG_PATH
-       if build_dir:
-               kunitconfig_path = os.path.join(build_dir, KUNITCONFIG_PATH)
-       return kunitconfig_path
+       return get_file_path(build_dir, KUNITCONFIG_PATH)
 
 def get_outfile_path(build_dir):
-       outfile_path = OUTFILE_PATH
-       if build_dir:
-               outfile_path = os.path.join(build_dir, OUTFILE_PATH)
-       return outfile_path
+       return get_file_path(build_dir, OUTFILE_PATH)
 
 class LinuxSourceTree(object):
        """Represents a Linux kernel source tree with KUnit tests."""