#!/bin/bash
echo "This script will create a crontab script and process check"
echo "script which will use a pid file to ensure that a process"
echo "is still running."
echo "Enter the working directory. We will cd here if needed to run the binary: "
mypwd=`pwd`
echo "Working Directory [$mypwd]:"
read workingdir;
if [ "$workingdir" = "" ]; then
  workingdir="$mypwd"
fi

echo "Enter the command to run:"
read bin
if [ "$bin" = "" ]; then
  echo "You must type in a command to run."
  exit 1
fi

echo "Enter the pid file [$mypwd/$bin.pid]:"
read pidfile
if [ "$pidfile" = "" ]; then
  pidfile="$mypwd/$bin.pid"
fi

echo "Give me an output file for this script to save to:"
read outputfile
if [ "$outputfile" = "" ]; then
  echo "No output file specified. Exiting."
  exit 3
fi


echo "#!/bin/bash" > $outputfile
echo "#" >> $outputfile
echo "# This is a script suitable for use in a crontab.  It checks to make sure" >> $outputfile
echo "# your process is running.  YOU NEED A SEPARATE CRON JOB FOR EACH PROCESS." >> $outputfile
echo "# If the procdess isn't found, it'll try to start it back up." >> $outputfile
echo "#" >> $outputfile
echo "# You'll need to edit this script for your process." >> $outputfile
echo "#" >> $outputfile
echo "# To check every 10 minutes, put the following line in your" >> $outputfile
echo "# crontab:" >> $outputfile
echo "#    0,10,20,30,40,50 * * * *   $mypwd/$outputfile" >> $outputfile
echo "# And if you don't want to get email from crontab when it checks your process," >> $outputfile
echo "# put the following in your crontab:" >> $outputfile
echo "#    0,10,20,30,40,50 * * * *   $mypwd/$outputfile >/dev/null 2>&1" >> $outputfile
echo "#" >> $outputfile
echo "workingdir=\"$workingdir\"" >> $outputfile
echo "bin=\"$bin\"" >> $outputfile
echo "pidfile=\"$pidfile\"" >> $outputfile

echo "if test -r \$pidfile; then" >> $outputfile
echo "  # there is a pid file -- is it current?" >> $outputfile
echo "  pid=\`cat \$pidfile\`" >> $outputfile
echo "  if \`kill -CHLD \$pid >/dev/null 2>&1\`; then" >> $outputfile
echo "    # it's still going" >> $outputfile
echo "    # back out quietly" >> $outputfile
echo "    exit 0" >> $outputfile
echo "  fi" >> $outputfile
echo "  echo \"Crontab notice:\"" >> $outputfile
echo "  echo \"\"" >> $outputfile
echo "  echo \"Stale \$pidfile file (erasing it)\"" >> $outputfile
echo "  rm -f \$pidfile" >> $outputfile
echo "fi" >> $outputfile
echo "echo \"\"" >> $outputfile
echo "echo \"Couldn't find \$bin running.  Reloading it...\"" >> $outputfile
echo "echo \"\"" >> $outputfile
echo "cd \$workingdir" >> $outputfile
echo "./\$bin" >> $outputfile
chmod +x $outputfile