#!/usr/bin/env python # # Copyright (C) 2009 The Android Open Source Project # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # # # Finds differences between two target files packages # from __future__ import print_function import argparse import contextlib import os import re import subprocess import sys import tempfile def ignore(name): """ Files to ignore when diffing These are packages that we're already diffing elsewhere, or files that we expect to be different for every build, or known problems. """ # We're looking at the files that make the images, so no need to search them if name in ['IMAGES']: return True # These are packages of the recovery partition, which we're already diffing if name in ['SYSTEM/etc/recovery-resource.dat', 'SYSTEM/recovery-from-boot.p']: return True # These files are just the BUILD_NUMBER, and will always be different if name in ['BOOT/RAMDISK/selinux_version', 'RECOVERY/RAMDISK/selinux_version']: return True return False def rewrite_build_property(original, new): """ Rewrite property files to remove values known to change for every build """ skipped = ['ro.bootimage.build.date=', 'ro.bootimage.build.date.utc=', 'ro.bootimage.build.fingerprint=', 'ro.build.id=', 'ro.build.display.id=', 'ro.build.version.incremental=', 'ro.build.date=', 'ro.build.date.utc=', 'ro.build.host=', 'ro.build.user=', 'ro.build.description=', 'ro.build.fingerprint=', 'ro.vendor.build.date=', 'ro.vendor.build.date.utc=', 'ro.vendor.build.fingerprint='] for line in original: skip = False for s in skipped: if line.startswith(s): skip = True break if not skip: new.write(line.encode()) def trim_install_recovery(original, new): """ Rewrite the install-recovery script to remove the hash of the recovery partition. """ for line in original: new.write(re.sub(r'[0-9a-f]{40}', '0'*40, line).encode()) def sort_file(original, new): """ Sort the file. Some OTA metadata files are not in a deterministic order currently. """ lines = original.readlines() lines.sort() for line in lines: new.write(line.encode()) # Map files to the functions that will modify them for diffing REWRITE_RULES = { 'BOOT/RAMDISK/default.prop': rewrite_build_property, 'RECOVERY/RAMDISK/default.prop': rewrite_build_property, 'SYSTEM/build.prop': rewrite_build_property, 'VENDOR/build.prop': rewrite_build_property, 'SYSTEM/bin/install-recovery.sh': trim_install_recovery, 'META/boot_filesystem_config.txt': sort_file, 'META/filesystem_config.txt': sort_file, 'META/recovery_filesystem_config.txt': sort_file, 'META/vendor_filesystem_config.txt': sort_file, } @contextlib.contextmanager def preprocess(name, filename): """ Optionally rewrite files before diffing them, to remove known-variable information. """ if name in REWRITE_RULES: with tempfile.NamedTemporaryFile() as newfp: with open(filename, 'r') as oldfp: REWRITE_RULES[name](oldfp, newfp) newfp.flush() yield newfp.name else: yield filename def diff(name, file1, file2, out_file): """ Diff a file pair with diff, running preprocess() on the arguments first. """ with preprocess(name, file1) as f1: with preprocess(name, file2) as f2: proc = subprocess.Popen(['diff', f1, f2], stdout=subprocess.PIPE, stderr=subprocess.STDOUT) (stdout, _) = proc.communicate() if proc.returncode == 0: return stdout = stdout.strip() if stdout == 'Binary files %s and %s differ' % (f1, f2): print("%s: Binary files differ" % name, file=out_file) else: for line in stdout.strip().split(b'\n'): print("%s: %s" % (name, line), file=out_file) def recursiveDiff(prefix, dir1, dir2, out_file): """ Recursively diff two directories, checking metadata then calling diff() """ list1 = sorted(os.listdir(dir1)) list2 = sorted(os.listdir(dir2)) for entry in list1: name = os.path.join(prefix, entry) name1 = os.path.join(dir1, entry) name2 = os.path.join(dir2, entry) if ignore(name): continue if entry in list2: if os.path.islink(name1) and os.path.islink(name2): link1 = os.readlink(name1) link2 = os.readlink(name2) if link1 != link2: print("%s: Symlinks differ: %s vs %s" % (name, link1, link2), file=out_file) continue elif os.path.islink(name1) or os.path.islink(name2): print("%s: File types differ, skipping compare" % name, file=out_file) continue stat1 = os.stat(name1) stat2 = os.stat(name2) type1 = stat1.st_mode & ~0o777 type2 = stat2.st_mode & ~0o777 if type1 != type2: print("%s: File types differ, skipping compare" % name, file=out_file) continue if stat1.st_mode != stat2.st_mode: print("%s: Modes differ: %o vs %o" % (name, stat1.st_mode, stat2.st_mode), file=out_file) if os.path.isdir(name1): recursiveDiff(name, name1, name2, out_file) elif os.path.isfile(name1): diff(name, name1, name2, out_file) else: print("%s: Unknown file type, skipping compare" % name, file=out_file) else: print("%s: Only in base package" % name, file=out_file) for entry in list2: name = os.path.join(prefix, entry) name1 = os.path.join(dir1, entry) name2 = os.path.join(dir2, entry) if ignore(name): continue if entry not in list1: print("%s: Only in new package" % name, file=out_file) def main(): parser = argparse.ArgumentParser() parser.add_argument('dir1', help='The base target files package (extracted)') parser.add_argument('dir2', help='The new target files package (extracted)') parser.add_argument('--output', help='The output file, otherwise it prints to stdout') args = parser.parse_args() if args.output: out_file = open(args.output, 'w') else: out_file = sys.stdout recursiveDiff('', args.dir1, args.dir2, out_file) if args.output: out_file.close() if __name__ == '__main__': main()