Small parser using Construct for the Linux kernel log buffer

parse_dmesg.py

#!/usr/bin/env python

from datetime import timedelta
import sys
from construct import *

Message = Aligned(4, Struct(                             
    "ts_nsec"    / Int64ul,
    "length"     / Int16ul,
    "text_len"   / Int16ul,
    "dict_len"   / Int16ul,
    "facility"   / Int8ul,
    "bits"       / Bitwise(Struct(
        "flags"  / BitsInteger(5),
        "level"  / BitsInteger(3),
    )),
    "text"       / PaddedString(this.text_len, "utf8"),
    "dictionary" / PaddedString(this.dict_len, "utf8"),
))

dmesg = GreedyRange(Message)

if __name__ == "__main__":
        for entry in dmesg.parse_file(sys.argv[1]):
                if entry.text_len:
                        print timedelta(seconds=entry.ts_nsec/1000000000), entry.text
                if entry.dict_len:
                        for kvp in entry.dictionary.split("\x00"):
                                print "   ",kvp