diff-kernel-logs

#!/bin/bash -eu
#
# Diff two kernel logs
#

function filter()
{
	local infile=${1}

	python3 -c "
import re
import sys

with open('${infile}') as fh:
    for line in fh:
        line = line.strip()

        line = re.sub(r'^\[[^\]]+\] ', '', line)
        line = re.sub(r'\d+ MB/', 'xxx MB/', line)
        print(line)
"
}

function usage()
{
	cat <<EOF
Usage: $(basename "${0}") [-h] [-s] INFILE1 INFILE2

Diff two kernel logs (dmesg).

Optinal arguments:
  -h, --help  Show this help text and exit.
  -s, --sort  Sort the logs before the diff.
EOF
}

p="cat"
infile1=
infile2=

while [ ${#} -ne 0 ] ; do
	case "${1}" in
		-h|--help)
			usage
			exit
			;;
		-s|--sort)
			p="sort"
			;;
		*)
			if [ -z "${infile1}" ] ; then
				infile1=${1}
			elif [ -z "${infile2}" ] ; then
				infile2=${1}
			else
				echo "Invalid argument: ${1}" >&2
				exit 2
			fi
			;;
	esac
	shift
done

if [ -z "${infile1}" ] || [ -z "${infile2}" ] ; then
	usage
	exit 2
fi

trap "rm -f /tmp/.{1,2}" INT TERM EXIT HUP

filter "${infile1}" | "${p}" > /tmp/.1
filter "${infile2}" | "${p}" > /tmp/.2

colordiff -y -W "$(tput cols)" /tmp/.1 /tmp/.2 || true
rm -f /tmp/.1 /tmp/.2