#!/bin/sh
# -*- sh -*-
#
# Plugin to monitor network connection activity using a subset of data from /proc/net/netstat
#
# Parameters:
#
#   config   (required)
#   autoconf (optional - only used by munin-config)
#
# Environment variables (optional):
#
#   IGNORED_FIELDS: comma-separated list of regexs for fields to ignore
#
# Author: Ted Dumitrescu (ted@mixpanel.com, webdev@cmme.org)
#
# Magic markers (optional - used by munin-config and some installation
# scripts):
#%# family=auto
#%# capabilities=autoconf


NETSTATS="/proc/net/netstat"

if [ -z $IGNORED_FIELDS ]; then
  IGNORED_FIELDS='TW\.,TCPPrequeued,TCPDirectCopy,TCPHPHits,TCPPureAcks,TCPHPAcks,TCPRcvCoalesce'
fi

TO_REMOVE=`echo $IGNORED_FIELDS | sed 's/,/\\\|/g'`
STRIP_OUTPUT="/\($TO_REMOVE\)/d"

if [ "$1" = "autoconf" ]; then
  if [ -r $NETSTATS ]; then
    echo yes
  else
    echo no
  fi
  exit 0
fi

if [ "$1" = "config" ]; then
  echo 'graph_title Netstat'
  echo 'graph_args -l 0 --base 1000'
  echo 'graph_category network'
  echo 'graph_period second'
  echo 'graph_info TcpExt stats'

  awk 'NR < 2 { for (i=2; i<=NF; i++) { printf("%s.label %s\n%s.type DERIVE\n%s.min 0\n", $i, $i, $i, $i); } }' $NETSTATS | sed "$STRIP_OUTPUT"
  exit 0
fi

awk 'NR < 2 { for (i=2; i<=NF; i++) { fn[i]=$i; }; getline; for (i=2; i<=NF; i++) { printf("%s.value %s\n", fn[i], $i); } }' $NETSTATS | sed "$STRIP_OUTPUT"