1#!/usr/bin/env python3
2#
3# Copyright (C) 2020 The Android Open Source Project
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16#
17
18# A tool that can take two logcat files from an Android device
19# and produce a compact rendering of the delta between them
20# Namely, it strips most of the information from the output
21# (timestamp, process id, ...) that is often not critical in
22# reconstructing the state of the device operation
23# and then compares the component and message for each line
24
25# It requires 'diff' and 'colordiff' to be installed
26
27import argparse
28import os.path
29import re
30import subprocess
31import sys
32import tempfile
33
34RE_TEXT = '^[\d]+-[\d]+ [\d]+:[\d]+:[\d]+.[\d]+[ ]+[\d]+[ ]+[\d]+ [DIEWF] (?P<component>.+): (?P<message>.*)$'
35
36# TODO(egranata): should we also support a by-component mode?
37class Logcat(object):
38    def __init__(self, fp, keep_mismatches=False):
39        self.filename = fp
40        self.mismatches = 0
41        self.messages = []
42        self.rgx = re.compile(RE_TEXT, re.MULTILINE)
43        with open(fp, 'r') as f:
44            for line in f.readlines():
45                match = self.rgx.match(line)
46                if match:
47                    component = match.group('component')
48                    message = match.group('message')
49                    self.messages.append("%s: %s" % (component, message))
50                elif keep_mismatches:
51                    self.messages.append(line)
52                else:
53                    self.mismatches += 1
54    def save(self):
55        # Keep this file around so we can use it by name elsewhere
56        with tempfile.NamedTemporaryFile(mode='w',
57            delete=False, prefix=os.path.basename(self.filename)) as f:
58            for msg in self.messages:
59                f.write("%s\n" % msg)
60            return f
61
62def entry():
63    parser = argparse.ArgumentParser(description='Compare two Android logs')
64    parser.add_argument('files', metavar='<file>', type=str, nargs=2,
65                    help='The two files to compare')
66    parser.add_argument('--keep-misformatted-lines', '-k', action='store_true', default=False)
67    args = parser.parse_args()
68
69    logcat1 = Logcat(args.files[0],
70        keep_mismatches=args.keep_misformatted_lines)
71    logcat2 = Logcat(args.files[1],
72        keep_mismatches=args.keep_misformatted_lines)
73
74    file1 = logcat1.save()
75    file2 = logcat2.save()
76
77    if logcat1.mismatches != 0 or logcat2.mismatches != 0:
78        print("%d lines were ignored; run with --keep-misformatted-lines to include them" \
79            % (logcat1.mismatches + logcat2.mismatches))
80
81    out = subprocess.getoutput('diff --minimal -u -W 200 "%s" "%s" | colordiff' % ( \
82            file1.name, file2.name))
83    print(out)
84
85    os.remove(file1.name)
86    os.remove(file2.name)
87
88if __name__ == '__main__':
89    entry()
90