1 files changed, 89 insertions, 0 deletions
diff --git a/tools/testing/kunit/kunit_config.py b/tools/testing/kunit/kunit_config.py
new file mode 100644
index 000000000..b30e9d6db
--- /dev/null
+++ b/tools/testing/kunit/kunit_config.py
@@ -0,0 +1,89 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Builds a .config from a kunitconfig.
+#
+# Copyright (C) 2019, Google LLC.
+# Author: Felix Guo <felixguoxiuping@gmail.com>
+# Author: Brendan Higgins <brendanhiggins@google.com>
+
+import collections
+import re
+
+CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$'
+CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$'
+
+KconfigEntryBase = collections.namedtuple('KconfigEntryBase', ['name', 'value'])
+
+class KconfigEntry(KconfigEntryBase):
+
+	def __str__(self) -> str:
+		if self.value == 'n':
+			return r'# CONFIG_%s is not set' % (self.name)
+		else:
+			return r'CONFIG_%s=%s' % (self.name, self.value)
+
+
+class KconfigParseError(Exception):
+	"""Error parsing Kconfig defconfig or .config."""
+
+
+class Kconfig(object):
+	"""Represents defconfig or .config specified using the Kconfig language."""
+
+	def __init__(self):
+		self._entries = []
+
+	def entries(self):
+		return set(self._entries)
+
+	def add_entry(self, entry: KconfigEntry) -> None:
+		self._entries.append(entry)
+
+	def is_subset_of(self, other: 'Kconfig') -> bool:
+		for a in self.entries():
+			found = False
+			for b in other.entries():
+				if a.name != b.name:
+					continue
+				if a.value != b.value:
+					return False
+				found = True
+			if a.value != 'n' and found == False:
+				return False
+		return True
+
+	def write_to_file(self, path: str) -> None:
+		with open(path, 'w') as f:
+			for entry in self.entries():
+				f.write(str(entry) + '\n')
+
+	def parse_from_string(self, blob: str) -> None:
+		"""Parses a string containing KconfigEntrys and populates this Kconfig."""
+		self._entries = []
+		is_not_set_matcher = re.compile(CONFIG_IS_NOT_SET_PATTERN)
+		config_matcher = re.compile(CONFIG_PATTERN)
+		for line in blob.split('\n'):
+			line = line.strip()
+			if not line:
+				continue
+
+			match = config_matcher.match(line)
+			if match:
+				entry = KconfigEntry(match.group(1), match.group(2))
+				self.add_entry(entry)
+				continue
+
+			empty_match = is_not_set_matcher.match(line)
+			if empty_match:
+				entry = KconfigEntry(empty_match.group(1), 'n')
+				self.add_entry(entry)
+				continue
+
+			if line[0] == '#':
+				continue
+			else:
+				raise KconfigParseError('Failed to parse: ' + line)
+
+	def read_from_file(self, path: str) -> None:
+		with open(path, 'r') as f:
+			self.parse_from_string(f.read())