#!/bin/zsh
# Filename:      grml-swapon
# Purpose:       activate swap partitions with taking care of suspend signatures
# Authors:       grml-team (grml.org), (c) Michael Prokop <mika@grml.org>
# Bug-Reports:   see http://grml.org/bugs/
# License:       This file is licensed under the GPL v2.
################################################################################

set -e # exit on any error

. /etc/grml/script-functions
. /etc/grml/lsb-functions
. /etc/grml/autoconfig.functions

check4root || exit 1
check4progs dd blkid swapon || exit 2

checkbootparam "anyswap" && export ANYSWAP='yes' || export ANYSWAP=""

case $1 in
   --force)
     ANYSWAP='yes'
     ;;
   -h*|--h*)
     ewarn 'grml-swapon: activate swap partitions defined in /etc/fstab'
     eindent
       ewarn 'Usage: grml-swapon [--help|-h] [--force]'
       ewarn 'Tip: execute grml-rebuildfstab for rebuilding /etc/fstab'
     eoutdent
     eend 1
     ;;
esac

einfo "Searching for swap partition(s) as requested."
eindent

[ -n "$ANYSWAP" ] && einfo "Option --force set, forcing usage of swap partitions."

while read p m f relax; do
  case "$p" in *fd0*|*proc*|*sys*|*\#*) continue;; esac
  partoptions="users,exec"
  fnew=""
  case "$f" in swap)
     case "$(dd if=$p bs=1 count=6 skip=4086 2>/dev/null)" in
             S1SUSP|S2SUSP|pmdisk|[zZ]*)
                if [ -n "$ANYSWAP" ] ; then
                  einfo "Using swap partition ${WHITE}${p}${NORMAL} [bootoption anyswap found]."
                  swapon $p 2>>$DEBUG ; eend $?
                else
                  ewarn "Suspend signature on ${WHITE}${p}${NORMAL} found, not using as swap. Force usage via option: --force"
                fi
               ;;
             *)
                if [[ "$p" == LABEL* ]] ; then
                   p=$(blkid -t $p | awk -F: '{print $1}')
                fi
                if grep -q $p /proc/swaps ; then
                   ewarn "Not using swap partition ${WHITE}${p}${NORMAL} as it is already in use." ; eend 0
                else
                   einfo "Using swap partition ${WHITE}${p}${NORMAL}."
                   swapon $p 2>>$DEBUG ; eend $?
                fi
               ;;
     esac
   continue
   ;;
  esac
 done <<EOT
$(cat /etc/fstab)
EOT

eoutdent