#!/bin/bash
# -*- sh -*-

: << =cut

=head1 NAME

lxc_proc - Plugin to monitor LXC Processes count

=head1 CONFIGURATION

env.cgrouppath - Set the path where 'tasks' sysfs files are stored, default: empty

  [lxc_proc]
    user root
    env.cgrouppath /sys/fs/cgroup/cpuacct/lxc/

=head1 INTERPRETATION

This plugin needs root privilege.

=head1 AUTHOR

vajtsz  vajtsz@gmail.com
(many changes schaefer@alphanet.ch)

=head1 LICENSE

2-clause BSD License
or GPLv3 license, at your option

=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=cut

. $MUNIN_LIBDIR/plugins/plugin.sh

. $MUNIN_LIBDIR/plugins/lxc-lib

active_guests=$(active_guests)

## find proper sysfs and count it
# Debian 6.0: /sys/fs/cgroup/<container>/tasks
# Ubuntu 12.04 with fstab: /sys/fs/cgroup/lxc/<container>/tasks
# Ubuntu 12.04 with cgroup-lite: /sys/fs/cgroup/cpuacct/lxc/<container>/tasks
# Ubuntu 12.04 with cgroup-bin: /sys/fs/cgroup/cpuacct/sysdefault/lxc/<container>/tasks
# and with cgmanager on jessie
count_processes () {
    [ -z "$1" ] && return 0

    if [ -n "$cgrouppath" ]; then
        SYSFS=$cgrouppath/$1/tasks
        if [ -e $SYSFS ]; then
            return `wc -l < $SYSFS`
        fi
    fi
    
    for SYSFS in \
        /sys/fs/cgroup/$1/tasks \
        /sys/fs/cgroup/lxc/$1/tasks \
        /sys/fs/cgroup/cpuacct/lxc/$1/tasks \
        /sys/fs/cgroup/cpuacct/sysdefault/lxc/$1/tasks \
    ; do
        if [ -e $SYSFS ]; then
            return `wc -l < $SYSFS`
        fi
    done

    if [ -e /usr/bin/cgm ]; then
      return `cgm getvalue cpu lxc/$1 tasks 2>/dev/null | wc -l`
    fi
    
    return 0
}

if [ "$1" = "autoconf" ]; then
   if [ -r /proc/stat ]; then
      echo yes
      exit 0
   else
      echo "no (no /proc/stat)"
      exit 0
   fi
fi

if [ "$1" = "config" ]; then
   cat <<EOF
graph_title Processes
graph_args -l 0 --base 1000
graph_vlabel Number of processes
graph_category lxc
EOF
 
   for n in $active_guests
   do 
      g=$(lxc_clean_fieldname $n)
      cat <<EOF
lxc_proc_${g}.label $n: processes
lxc_proc_${g}.type GAUGE
lxc_proc_${g}.min 0
EOF
   done
   exit 0
fi

for n in $active_guests
do
   g=$(lxc_clean_fieldname $n)
   
   count_processes $n
   tmp_g=$?
   if [ $tmp_g -eq 0 ]; then
     tmp_g=$(lxc_cgroup -n $n tasks | wc -l)
   fi
   echo "lxc_proc_${g}.value $tmp_g"
done