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
11from typing import List, Set
12
13CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$'
14CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$'
15
16KconfigEntryBase = collections.namedtuple('KconfigEntry', ['name', 'value'])
17
18class KconfigEntry(KconfigEntryBase):
19
20	def __str__(self) -> str:
21		if self.value == 'n':
22			return r'# CONFIG_%s is not set' % (self.name)
23		else:
24			return r'CONFIG_%s=%s' % (self.name, self.value)
25
26
27class KconfigParseError(Exception):
28	"""Error parsing Kconfig defconfig or .config."""
29
30
31class Kconfig(object):
32	"""Represents defconfig or .config specified using the Kconfig language."""
33
34	def __init__(self) -> None:
35		self._entries = []  # type: List[KconfigEntry]
36
37	def entries(self) -> Set[KconfigEntry]:
38		return set(self._entries)
39
40	def add_entry(self, entry: KconfigEntry) -> None:
41		self._entries.append(entry)
42
43	def is_subset_of(self, other: 'Kconfig') -> bool:
44		for a in self.entries():
45			found = False
46			for b in other.entries():
47				if a.name != b.name:
48					continue
49				if a.value != b.value:
50					return False
51				found = True
52			if a.value != 'n' and found == False:
53				return False
54		return True
55
56	def write_to_file(self, path: str) -> None:
57		with open(path, 'w') as f:
58			for entry in self.entries():
59				f.write(str(entry) + '\n')
60
61	def parse_from_string(self, blob: str) -> None:
62		"""Parses a string containing KconfigEntrys and populates this Kconfig."""
63		self._entries = []
64		is_not_set_matcher = re.compile(CONFIG_IS_NOT_SET_PATTERN)
65		config_matcher = re.compile(CONFIG_PATTERN)
66		for line in blob.split('\n'):
67			line = line.strip()
68			if not line:
69				continue
70
71			match = config_matcher.match(line)
72			if match:
73				entry = KconfigEntry(match.group(1), match.group(2))
74				self.add_entry(entry)
75				continue
76
77			empty_match = is_not_set_matcher.match(line)
78			if empty_match:
79				entry = KconfigEntry(empty_match.group(1), 'n')
80				self.add_entry(entry)
81				continue
82
83			if line[0] == '#':
84				continue
85			else:
86				raise KconfigParseError('Failed to parse: ' + line)
87
88	def read_from_file(self, path: str) -> None:
89		with open(path, 'r') as f:
90			self.parse_from_string(f.read())
91