selinux-policy/ifndefy.py

81 lines
2.8 KiB
Python
Raw Normal View History

#!/usr/bin/env python3
#
# Copyright (C) 2021 Red Hat, Inc.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library. If not, see
# <http://www.gnu.org/licenses/>.
# About:
# When provided with an interface file, this script outputs a new interface
# file, where all original interfaces are enclosed in an ifndef statement
# dependent on their name. All indentation inside the interface file should
# be converted to tabs before running this script.
#
# Known issues:
# - interface already enclosed in an ifndef statement is not ignored
# - "`" and "'" inside comments are not ignored
# - \t is always used for indentation - may result in mixture of spaces and tabs
import sys
import os
import re
if len(sys.argv) < 1:
print(("Usage: {} <policy>.if > <output>.if").format(sys.argv[0]), file=sys.stderr)
exit(os.EX_USAGE)
# ending index of interface
end = 0
with open(sys.argv[1], 'r') as f:
interfaces = f.read()
file_len = len(interfaces)
while end < file_len:
start = interfaces.find("interface(`", end)
if start < 0:
#no more interfaces
print(interfaces[end:], end ="")
break
name_end = interfaces.find("'", start+11)
name = interfaces[start+11:name_end]
# locate the end of the interface - i.e. ending apostrophe
reg = re.compile(r"[`']")
# skip the ' after interface name
i = name_end+1
# counter for the depth (` opens a new block, while ' closes it)
graves = 0
while i < file_len:
match = reg.search(interfaces, i)
if not match:
print("Malformed interface: {}".format(name), file=sys.stderr)
exit(1)
i = match.end()
if match.group(0) == '`':
graves += 1
else:
graves -= 1
if graves == 0:
break
# keep everything between the end of previous interface and start of a new one
print(interfaces[end:start], end ="")
# interface ends in "')" -- add 1 for the edning bracket
end = i+1
# print the whole interface enclosed in "ifndef"
print("ifndef(`{}',`".format(name))
print('\n'.join([('\t' + x) if x else x for x in interfaces[start:end].split('\n')]))
print("')", end ="")