How to use the portage.os.listdir function in portage

def AddPackagesInDir(path):
		""" Given a list of dirs, add any packages in it """
		ret = []
		pkgdirs = os.listdir(path)
		for d in pkgdirs:
			if d == 'CVS' or d.startswith('.'):
				continue
			p = os.path.join(path, d)

			if os.path.isdir(p):
				cat_pkg_dir = os.path.join(*p.split(os.path.sep)[-2:])
				logging.debug('adding %s to scanlist' % cat_pkg_dir)
				ret.append(cat_pkg_dir)
		return ret

mtime = pathstat.st_mtime
		else:
			raise DirectoryNotFound(mypath)
	except EnvironmentError as e:
		if e.errno == PermissionDenied.errno:
			raise PermissionDenied(mypath)
		del e
		return [], []
	except PortageException:
		return [], []
	# Python retuns mtime in seconds, so if it was changed in the last few seconds, it could be invalid
	if mtime != cached_mtime or time.time() - mtime < 4:
		if mypath in dircache:
			cacheStale += 1
		try:
			list = os.listdir(mypath)
		except EnvironmentError as e:
			if e.errno != errno.EACCES:
				raise
			del e
			raise PermissionDenied(mypath)
		ftype = []
		for x in list:
			try:
				if followSymlinks:
					pathstat = os.stat(mypath+"/"+x)
				else:
					pathstat = os.lstat(mypath+"/"+x)

				if stat.S_ISREG(pathstat[stat.ST_MODE]):
					ftype.append(0)
				elif stat.S_ISDIR(pathstat[stat.ST_MODE]):

def listdir(p, **kwargs):
				try:
					return [x for x in os.listdir(p) \
						if os.path.isdir(os.path.join(p, x))]
				except EnvironmentError as e:
					if e.errno == PermissionDenied.errno:
						raise PermissionDenied(p)
					del e
					return []

for subdir in kwargs["subdirs"]:
						mydirs.append(os.path.join(basedir, subdir))
				for mydir in mydirs:
					modified = ensure_dirs(mydir)
					# Generally, we only want to apply permissions for
					# initial creation.  Otherwise, we don't know exactly what
					# permissions the user wants, so should leave them as-is.
					droppriv_fix = False
					if droppriv:
						st = os.stat(mydir)
						if st.st_gid != portage_gid or \
							not dirmode == (stat.S_IMODE(st.st_mode) & dirmode):
							droppriv_fix = True
						if not droppriv_fix:
							# Check permissions of files in the directory.
							for filename in os.listdir(mydir):
								try:
									subdir_st = os.lstat(
										os.path.join(mydir, filename))
								except OSError:
									continue
								if subdir_st.st_gid != portage_gid or \
									((stat.S_ISDIR(subdir_st.st_mode) and \
									not dirmode == (stat.S_IMODE(subdir_st.st_mode) & dirmode))):
									droppriv_fix = True
									break

					if droppriv_fix:
						_adjust_perms_msg(mysettings,
							colorize("WARN", " * ") + \
							_("Adjusting permissions "
							"for FEATURES=userpriv: '%s'\n") % mydir)

def fixdbentries(update_iter, dbdir, eapi=None, parent=None):
	"""Performs update commands which result in search and replace operations
	for each of the files in dbdir (excluding CONTENTS and environment.bz2).
	Returns True when actual modifications are necessary and False otherwise."""

	warnings.warn("portage.update.fixdbentries() is deprecated",
		DeprecationWarning, stacklevel=2)

	mydata = {}
	for myfile in [f for f in os.listdir(dbdir) if f not in ignored_dbentries]:
		file_path = os.path.join(dbdir, myfile)
		with io.open(_unicode_encode(file_path,
			encoding=_encodings['fs'], errors='strict'),
			mode='r', encoding=_encodings['repo.content'],
			errors='replace') as f:
			mydata[myfile] = f.read()
	updated_items = update_dbentries(update_iter, mydata,
		eapi=eapi, parent=parent)
	for myfile, mycontent in updated_items.items():
		file_path = os.path.join(dbdir, myfile)
		write_atomic(file_path, mycontent, encoding=_encodings['repo.content'])
	return len(updated_items) > 0

def cacheddir(my_original_path, ignorecvs, ignorelist, EmptyOnError, followSymlinks=True):
	mypath = normalize_path(my_original_path)
	try:
		pathstat = os.stat(mypath)
		if not stat.S_ISDIR(pathstat.st_mode):
			raise DirectoryNotFound(mypath)
	except EnvironmentError as e:
		if e.errno == PermissionDenied.errno:
			raise PermissionDenied(mypath)
		del e
		return [], []
	except PortageException:
		return [], []
	else:
		try:
			fpaths = os.listdir(mypath)
		except EnvironmentError as e:
			if e.errno != errno.EACCES:
				raise
			del e
			raise PermissionDenied(mypath)
		ftype = []
		for x in fpaths:
			try:
				if followSymlinks:
					pathstat = os.stat(mypath+"/"+x)
				else:
					pathstat = os.lstat(mypath+"/"+x)

				if stat.S_ISREG(pathstat[stat.ST_MODE]):
					ftype.append(0)
				elif stat.S_ISDIR(pathstat[stat.ST_MODE]):

finally:
			if f is not None:
				f.close()

		if intersecting_repos:
			allow_directories = eapi_allows_directories_on_profile_level_and_repository_level(eapi) or \
				any(x in _portage1_profiles_allow_directories for x in layout_data['profile-formats'])
			compat_mode = not eapi_allows_directories_on_profile_level_and_repository_level(eapi) and \
				layout_data['profile-formats'] == ('portage-1-compat',)
			allow_parent_colon = any(x in _allow_parent_colon
				for x in layout_data['profile-formats'])
			current_formats = tuple(layout_data['profile-formats'])


		if compat_mode:
			offenders = _PORTAGE1_DIRECTORIES.intersection(os.listdir(currentPath))
			offenders = sorted(x for x in offenders
				if os.path.isdir(os.path.join(currentPath, x)))
			if offenders:
				warnings.warn(_(
					"\nThe selected profile is implicitly using the 'portage-1' format:\n"
					"\tprofile = %(profile_path)s\n"
					"But this repository is not using that format:\n"
					"\trepo = %(repo_name)s\n"
					"This will break in the future.  Please convert these dirs to files:\n"
					"\t%(files)s\n"
					"Or, add this line to the repository's layout.conf:\n"
					"\tprofile-formats = portage-1")
					% dict(profile_path=currentPath, repo_name=repo_loc,
						files='\n\t'.join(offenders)))

		parentsFile = os.path.join(currentPath, "parent")

checkdir_relative = ""
			if self.repolevel < 3:
				checkdir_relative = os.path.join(pkgdir, checkdir_relative)
			if self.repolevel < 2:
				checkdir_relative = os.path.join(catdir, checkdir_relative)
			checkdir_relative = os.path.join(".", checkdir_relative)

			# Run the status check
			if self.kwargs['checks']['ebuild_notadded']:
				self.vcs_settings.status.check(checkdir, checkdir_relative, xpkg)

			if self.generate_manifest:
				manifest.Manifest(**self.kwargs).update_manifest(checkdir)
				if self.options.mode == 'manifest':
					continue
			checkdirlist = os.listdir(checkdir)

			dynamic_data = {
				'changelog_modified': False,
				'checkdirlist': ExtendedFuture(checkdirlist),
				'checkdir': checkdir,
				'xpkg': xpkg,
				'changed': self.changed,
				'checkdir_relative': checkdir_relative,
				'can_force': can_force,
				'repolevel': self.repolevel,
				'catdir': catdir,
				'pkgdir': pkgdir,
				'validity_future': ExtendedFuture(True),
				'y_ebuild': None,
				# this needs to be reset at the pkg level only,
				# easiest is to just initialize it here