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('KconfigEntryBase', ['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		other_dict = {e.name: e.value for e in other.entries()}
45		for a in self.entries():
46			b = other_dict.get(a.name)
47			if b is None:
48				if a.value == 'n':
49					continue
50				return False
51			elif a.value != b:
52				return False
53		return True
54
55	def merge_in_entries(self, other: 'Kconfig') -> None:
56		if other.is_subset_of(self):
57			return
58		self._entries = list(self.entries().union(other.entries()))
59
60	def write_to_file(self, path: str) -> None:
61		with open(path, 'a+') as f:
62			for entry in self.entries():
63				f.write(str(entry) + '\n')
64
65	def parse_from_string(self, blob: str) -> None:
66		"""Parses a string containing KconfigEntrys and populates this Kconfig."""
67		self._entries = []
68		is_not_set_matcher = re.compile(CONFIG_IS_NOT_SET_PATTERN)
69		config_matcher = re.compile(CONFIG_PATTERN)
70		for line in blob.split('\n'):
71			line = line.strip()
72			if not line:
73				continue
74
75			match = config_matcher.match(line)
76			if match:
77				entry = KconfigEntry(match.group(1), match.group(2))
78				self.add_entry(entry)
79				continue
80
81			empty_match = is_not_set_matcher.match(line)
82			if empty_match:
83				entry = KconfigEntry(empty_match.group(1), 'n')
84				self.add_entry(entry)
85				continue
86
87			if line[0] == '#':
88				continue
89			else:
90				raise KconfigParseError('Failed to parse: ' + line)
91
92	def read_from_file(self, path: str) -> None:
93		with open(path, 'r') as f:
94			self.parse_from_string(f.read())