#! /bin/sh
#
# $Id: mmdbsrv.wrapper,v 6.9 1998/10/07 21:58:16 kimelman Exp $
#
# this is CGI handler wrapper. It works as a membrane between httpd and actual
# cgi program and allow to run new technological version of such program in 
# parallel to old one and compare results in "real life" condition. 
#
# $Log: mmdbsrv.wrapper,v $
# Revision 6.9  1998/10/07 21:58:16  kimelman
# code cleaned & madeeasy to read.
# check for directory access permission added
# binaries expected names changed
# this version of script is expected to work on public servers
#
# Revision 6.8  1998/06/09 19:16:07  kimelman
# extra bracket removed.
#
# Revision 6.7  1998/06/09 18:50:35  kimelman
# permissions problems workaround added to wrapper
#
#

MMDBSRVs_to_try="./mmdbsrv.REAL ./mmdbsrv.NEW new/mmdbsrv.db"

progname=$0
progdir=`dirname $progname`
options="$*"

TMPtop=/tmp/mmdbsrv
TMPdir=$TMPtop/$$
awk_prg=$TMPtop/awkp
STATs_to_try="./stats log/statistics.mmdbsrv $TMPtop/stats"

check_executables() {

MMDBSRVs=
for fexec in $MMDBSRVs_to_try ; do
    [ ! -x $fexec ] || MMDBSRVs="$MMDBSRVs $fexec"
done

if [ "x$MMDBSRVs" = x ]; then
     mail $THEvictim <<EOF
Subject ${progname} : can find binaries to run

`ls -al`

EOF
    exit 1
fi
}

check_stats() {
    stats=
    for stats_file in $STATs_to_try ; do
        if [ -w $stats -a -w `dirname $stats` ]; then
            stats=$stats_file
            break
        fi
    done
    if [ x$stats = x ] ; then 
        for stats_file in $STATs_to_try ; do
            if [ -w `dirname $stats` ]; then
                stats=$stats_file
                break
            fi
        done
    fi
}

res_name() {
  res_fname=${TMPdir}/`echo "$1" | tr '/.' '__'`
  dir=`dirname $res_fname`
  [ -d  $dir ] || mkdir -p $dir
}

run_cgi() {
  res_name $1
  case $1 in 
  /* ) 
      prg="$1"
      ;;
  *) 
      prg="$progdir/$1"
      ;;
  esac
  (
   cd `dirname $prg`
   /usr/bin/time -p ./`basename $prg` $options <$input_file >$res_fname 2>$res_fname.2
  )  &
  waitedID="$waitedID $!"
}


report_lock_problem() {
     mail $THEvictim <<EOF
Subject mmdbsrv.wrapper locking problem

dd="$dd"
$stats.lock="`cat $stats.lock`"

`ls -al`

`ps -ef`

`set`

EOF
     exit 1
}

timing() {
    dd=$$
    while [ -f $stats.lock ] ; do sleep 1 ; done
    echo $dd >$stats.lock
    [ -f $stats ] || echo '! Stats file' >$stats
    if [ -f $stats.lock -a "$dd" != "`cat $stats.lock`" ] ; then
        report_lock_problem
    fi
    grep -v "^$fn " $stats > $res_fname.3
    grep "^$fn " $stats | cat $res_fname.2 -  >$res_fname.4
    nawk -v fn=$fn -f $awk_prg $res_fname.4 >>$res_fname.3
    cat $res_fname.3 >$stats
    rm $res_fname.3
    [ ! -f ${stats}.lock ] || rm ${stats}.lock
}

proc_res() {
  res_name $1
  fn=`basename $res_fname`
  # echo "proc_res: $1 --> $fn"
  if [ "x$rcode" != x -a $rcode -eq 0 -a x$stats != x ]; then
    timing
  fi
}

create_stats_prog() {
cat >$awk_prg <<EOF
BEGIN   { real=0 ; user=0 ; sys=0 ; cnt=0 ; }
/real/  { real=\$2 }
/user/  { user=\$2 }
/sys/   { sys=\$2  }
        { if ( \$1 == fn ) { cnt=\$5 ; real+=\$2 * cnt ;  user+=\$3 *cnt ; sys +=\$4 * cnt ;  } }
END     { cnt+=1 ; print fn, real/cnt, user/cnt, sys/cnt, cnt }
EOF
}

report_failure() { # $execname $rcode $res_fname $res_fname.2
    mail $THEvictim <<EOF
Subject: $1 failed with status $2

====================================================================
Log:
`cat $3`

Log.2:
`cat $4`

====================================================================
Input file:
`cat $input_file`

====================================================================
----------- Environment:----------------

`env`

EOF
}

atexit() {
    rm -rf $TMPdir
}
#-------------------------------------------------------------------
#-------------------------------------------------------------------
#  MAIN program 
#-------------------------------------------------------------------

[ -d $TMPtop ] || mkdir -p $TMPtop
[ -d $TMPdir ] || mkdir -p $TMPdir 
# just to make sure
chmod a+rw $TMPtop
chmod a+rw $TMPdir

trap atexit 0,1

# configuration

check_executables
check_stats

if [ x$stats != x ] ; then
    sybase_settings_fname=`dirname $stats`/.syb_set
fi

. ${progdir}/st_configure.sh

if [ ! -r $awk_prg ] ; then
    create_stats_prog
fi

# store input stream
res_name input
input_file=$res_fname
cat >$input_file

#
# run all cgi programs in parallel
#

for texec in $MMDBSRVs ; do
  run_cgi $texec
done

#
# wait for termination of all of them
#
main_result=

for execname in $MMDBSRVs ; do
  set -- $waitedID
  wid=$1 ; shift ; waitedID="$*"
  wait $wid
  rcode=$?
  proc_res $execname
  if [ $rcode -ne 0 ] ; then
    # report mmdbsrv.REAL failure
    report_failure $execname $rcode $res_fname $res_fname.2 
    continue
  fi 
  if [ x$main_result = x ] ; then
    main_result=$res_fname
    # output result of first program
    cat $main_result
    continue
  fi
  #
  # compare results now
  #
  diff -c $main_result $res_fname >$res_fname.diff
  if [ $? -gt 0 ] ; then
    report_failure $execname $rcode $res_fname.diff $res_fname.2
  fi
done

#
# The end
#
exit 0