#!/usr/bin/env sh
#
# usage: sudo bin/swap

: ${SIZE:=1G}
: ${SWAPFILE:=/swapfile}

if swapon -s | grep -q $SWAPFILE
then
  echo Swap is already on...
  exit
fi

fallocate -l $SIZE $SWAPFILE
chmod 600 $SWAPFILE
mkswap $SWAPFILE
swapon $SWAPFILE

if ! grep -q $SWAPFILE /etc/fstab
then
  cat << permanent_swap >> /etc/fstab
$SWAPFILE   none    swap    sw    0   0
permanent_swap
fi

if swapon -s | grep -q $SWAPFILE
then
  echo Swap is on...
fi