signaldiff

#!/usr/bin/env python3
#
#  Copyright (C) 2017, Jaguar Land Rover
#
#  This program is licensed under the terms and conditions of the
#  Mozilla Public License, version 2.0.  The full text of the 
#  Mozilla Public License is at https://www.mozilla.org/MPL/2.0/
#
#  Author:
#     Luis Araujo <luis.araujo@collabora.co.uk>

import re
import argparse

SIGNAL_MSG_PATTERN = '^(?P<direction>[<|>]) (?P<time>[\d\.]+),(?P<signal>[\w\.]+,(\[SIGNUM\]|\d+),[\w\'\"]+)$'

signal_pattern = re.compile(SIGNAL_MSG_PATTERN)


def run(args):
    file1 = args.LOG_FILE1
    file2 = args.LOG_FILE2

    print_sep = False
    def _print_diff(signalnum, filename, linenum, line, header=True):
        nonlocal print_sep

        if header:
            if print_sep:
                print()
            print('Signal', signalnum)

        print('{}:{}:'.format(filename, linenum), line)
        print_sep = True

    with open(file1) as f1, open(file2) as f2:
        signal_count = 0
        i = 0
        lines2 =  f2.readlines()
        lines2_length = len(lines2)

        line1_count = line2_count = 0

        for line1 in f1.readlines():
            line1_count += 1
            line1_s = line1.strip()

            if len(line1_s) == 0:
                continue

            line1_match = signal_pattern.match(line1_s)
            if not line1_match:
                continue

            signal_count += 1

            while i < lines2_length:
                line2_s = lines2[i].strip()
                line2_count += 1
                i += 1

                if len(line2_s) == 0:
                    continue

                line2_match = signal_pattern.match(line2_s)
                if line2_match:
                    notime_line1 = '{} {}'.format(line1_match.group('direction'),
                                                  line1_match.group('signal'))
                    notime_line2 = '{} {}'.format(line2_match.group('direction'),
                                                  line2_match.group('signal'))

                    if args.ignore_time:
                        cmp_line1 = notime_line1
                        cmp_line2 = notime_line2
                    else:
                        if args.time_deviation:
                            time1 = line1_match.group('time')
                            time2 = line2_match.group('time')

                            deviate = abs(float(time1) - float(time2)) > \
                                      args.time_deviation

                            if not deviate and (notime_line1 == notime_line2):
                                break

                        cmp_line1 = line1_s
                        cmp_line2 = line2_s

                    if cmp_line1 != cmp_line2:
                        _print_diff(signal_count, file1, line1_count, line1_s)
                        _print_diff(signal_count, file2, line2_count, line2_s, False)

                    break
            else:
                # Remaining lines for File 1 (if any).
                _print_diff(signal_count, file1, line1_count, line1_s)

        # Remaining lines for File 2 (if any).
        while i < lines2_length:
            line2_s = lines2[i].strip()
            line2_count += 1
            i += 1

            if len(line2_s) == 0:
                continue

            line2_match = signal_pattern.match(line2_s)
            if line2_match:
                signal_count += 1
                _print_diff(signal_count, file2, line2_count, line2_s)


if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('LOG_FILE1', type=str, help="Log file 1")
    parser.add_argument('LOG_FILE2', type=str, help="Log file 2")
    parser.add_argument('-i', '--ignore-time', action='store_true',
                        help='Ignore timestamps')
    parser.add_argument('-t', '--time-deviation', type=float,
                        help='Time deviation specified as a decimal number in '
                        'milliseconds (ms)')

    args = parser.parse_args()

    run(args)