1# SPDX-License-Identifier: GPL-2.0
2#
3# Builds a .config from a kunitconfig.
4#
5# Copyright (C) 2019, Google LLC.
6# Author: Felix Guo <felixguoxiuping@gmail.com>
7# Author: Brendan Higgins <brendanhiggins@google.com>
8
9import collections
10import re
11
12CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$'
13CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$'
14
15KconfigEntryBase = collections.namedtuple('KconfigEntry', ['name', 'value'])
16
17class KconfigEntry(KconfigEntryBase):
18
19	def __str__(self) -> str:
20		if self.value == 'n':
21			return r'# CONFIG_%s is not set' % (self.name)
22		else:
23			return r'CONFIG_%s=%s' % (self.name, self.value)
24
25
26class KconfigParseError(Exception):
27	"""Error parsing Kconfig defconfig or .config."""
28
29
30class Kconfig(object):
31	"""Represents defconfig or .config specified using the Kconfig language."""
32
33	def __init__(self):
34		self._entries = []
35
36	def entries(self):
37		return set(self._entries)
38
39	def add_entry(self, entry: KconfigEntry) -> None:
40		self._entries.append(entry)
41
42	def is_subset_of(self, other: 'Kconfig') -> bool:
43		for a in self.entries():
44			found = False
45			for b in other.entries():
46				if a.name != b.name:
47					continue
48				if a.value != b.value:
49					return False
50				found = True
51			if a.value != 'n' and found == False:
52				return False
53		return True
54
55	def write_to_file(self, path: str) -> None:
56		with open(path, 'w') as f:
57			for entry in self.entries():
58				f.write(str(entry) + '\n')
59
60	def parse_from_string(self, blob: str) -> None:
61		"""Parses a string containing KconfigEntrys and populates this Kconfig."""
62		self._entries = []
63		is_not_set_matcher = re.compile(CONFIG_IS_NOT_SET_PATTERN)
64		config_matcher = re.compile(CONFIG_PATTERN)
65		for line in blob.split('\n'):
66			line = line.strip()
67			if not line:
68				continue
69
70			match = config_matcher.match(line)
71			if match:
72				entry = KconfigEntry(match.group(1), match.group(2))
73				self.add_entry(entry)
74				continue
75
76			empty_match = is_not_set_matcher.match(line)
77			if empty_match:
78				entry = KconfigEntry(empty_match.group(1), 'n')
79				self.add_entry(entry)
80				continue
81
82			if line[0] == '#':
83				continue
84			else:
85				raise KconfigParseError('Failed to parse: ' + line)
86
87	def read_from_file(self, path: str) -> None:
88		with open(path, 'r') as f:
89			self.parse_from_string(f.read())
90