#!/bin/sh
#
# syslogtocern - convert thttpd syslog entries into CERN Combined Log Format
#
# Copyright © 1995,1998 by Jef Poskanzer <jef@mail.acme.com>.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.

if [ $# -lt 1 ] ; then
    echo "usage:  $0 logfile ..." >&2
    exit 1
fi

tmp1=/tmp/stc1.$$
rm -f $tmp1

# Gather up all the thttpd entries.
egrep -h ' thttpd\[' "$@" > $tmp1

# Figure out the current year - it's not in syslog's output.  Some versions
# of date have the %Y directive to give the full four-digit year, but others
# only have %y.
year=`date +%y`
if [ $year -gt 70 ] ; then
    year=19$year
else
    year=20$year
fi

# If the current year isn't the year that the logfile was generated, we need
# to fix it.  This will most likely happen once a year, when this script is
# run on January 1st for December 31st's logfile.  So, if the current month
# is January and there are December dates in the log file, we subtract one.
# This should cover most cases.
if [ `date +%m` -eq 1 -a `head -1 $tmp1 | awk '{print $1}'` = "Dec" ] ; then
    year=`echo $year - 1 | bc`
fi

# Do access_log.
awk < $tmp1 '{if ( NF >= 15 && $7 == "-" && $12 >= 100 && $12 < 510) print;}' |
  sed -e "s,\([A-Z][a-z][a-z]\) \([0-9 ][0-9]\) \([0-9][0-9]:[0-9][0-9]:[0-9][0-9]\) [^ ]* thttpd\[[0-9]*\]: \([^ ]* [^ ]* [^ ]*\) \(.*\),\4 [\2/\1/${year}:\3] \5," -e 's,\[ ,[0,' > access_log

# Do error_log.
awk < $tmp1 '{if ( ! ( NF >= 15 && $7 == "-" && $12 >= 100 && $12 < 510) ) print;}' |
  sed -e "s,\([A-Z][a-z][a-z] [0-9 ][0-9] [0-9][0-9]:[0-9][0-9]:[0-9][0-9]\) [^ ]* thttpd\[[0-9]*\]: \(.*\),[\1 ${year}] \2," > error_log

# Done.
rm -f $tmp1