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
9from dataclasses import dataclass
10import re
11from typing import Any, Dict, Iterable, List, Tuple
12
13CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$'
14CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$'
15
16@dataclass(frozen=True)
17class KconfigEntry:
18	name: str
19	value: str
20
21	def __str__(self) -> str:
22		if self.value == 'n':
23			return f'# CONFIG_{self.name} is not set'
24		return f'CONFIG_{self.name}={self.value}'
25
26
27class KconfigParseError(Exception):
28	"""Error parsing Kconfig defconfig or .config."""
29
30
31class Kconfig:
32	"""Represents defconfig or .config specified using the Kconfig language."""
33
34	def __init__(self) -> None:
35		self._entries = {}  # type: Dict[str, str]
36
37	def __eq__(self, other: Any) -> bool:
38		if not isinstance(other, self.__class__):
39			return False
40		return self._entries == other._entries
41
42	def __repr__(self) -> str:
43		return ','.join(str(e) for e in self.as_entries())
44
45	def as_entries(self) -> Iterable[KconfigEntry]:
46		for name, value in self._entries.items():
47			yield KconfigEntry(name, value)
48
49	def add_entry(self, name: str, value: str) -> None:
50		self._entries[name] = value
51
52	def is_subset_of(self, other: 'Kconfig') -> bool:
53		for name, value in self._entries.items():
54			b = other._entries.get(name)
55			if b is None:
56				if value == 'n':
57					continue
58				return False
59			if value != b:
60				return False
61		return True
62
63	def conflicting_options(self, other: 'Kconfig') -> List[Tuple[KconfigEntry, KconfigEntry]]:
64		diff = []  # type: List[Tuple[KconfigEntry, KconfigEntry]]
65		for name, value in self._entries.items():
66			b = other._entries.get(name)
67			if b and value != b:
68				pair = (KconfigEntry(name, value), KconfigEntry(name, b))
69				diff.append(pair)
70		return diff
71
72	def merge_in_entries(self, other: 'Kconfig') -> None:
73		for name, value in other._entries.items():
74			self._entries[name] = value
75
76	def write_to_file(self, path: str) -> None:
77		with open(path, 'a+') as f:
78			for e in self.as_entries():
79				f.write(str(e) + '\n')
80
81def parse_file(path: str) -> Kconfig:
82	with open(path, 'r') as f:
83		return parse_from_string(f.read())
84
85def parse_from_string(blob: str) -> Kconfig:
86	"""Parses a string containing Kconfig entries."""
87	kconfig = Kconfig()
88	is_not_set_matcher = re.compile(CONFIG_IS_NOT_SET_PATTERN)
89	config_matcher = re.compile(CONFIG_PATTERN)
90	for line in blob.split('\n'):
91		line = line.strip()
92		if not line:
93			continue
94
95		match = config_matcher.match(line)
96		if match:
97			kconfig.add_entry(match.group(1), match.group(2))
98			continue
99
100		empty_match = is_not_set_matcher.match(line)
101		if empty_match:
102			kconfig.add_entry(empty_match.group(1), 'n')
103			continue
104
105		if line[0] == '#':
106			continue
107		raise KconfigParseError('Failed to parse: ' + line)
108	return kconfig
109