create swap partition in all systems and enable swap partition on 1st boot in CE

As reported by Andrew CE systems tend to run in OOM conditions
pretty soon sometimes. So lets enable a swap partition in all
our systems by default.

To avoid a bigger VM image we create an init script on CE systems
which enables the swap partition during bootup and then destroys
itself (the script, not the swap partition :)).

From: Michael Prokop <mprokop@sipwise.com>

deployment.sh

@@ -608,23 +608,10 @@ fi
 echo "root:sipwise" | chpasswd
 
 ## partition disk
-# physical installation
-if [[ $(imvirt 2>/dev/null) == "Physical" ]] || $PRO_EDITION ; then
-  # remove existing partitioning
-  #  dd if=/dev/zero of=/dev/${DISK} bs=512 count=1
-  #  partprobe /dev/${DISK} ; sync
-
-  parted -s /dev/${DISK} mktable msdos
-  # hw-raid with rootfs + swap partition
-  parted -s /dev/${DISK} 'mkpart primary ext4 2048s 95%'
-  parted -s /dev/${DISK} 'mkpart primary linux-swap 95% -1'
-
-else # virtual installation
-  # just one disk, assuming VM installation without swap partition
-  parted -s /dev/${DISK} mktable msdos
-  parted -s /dev/${DISK} 'mkpart primary ext4 2048s 100%'
-fi
-
+parted -s /dev/${DISK} mktable msdos
+# hw-raid with rootfs + swap partition
+parted -s /dev/${DISK} 'mkpart primary ext4 2048s 95%'
+parted -s /dev/${DISK} 'mkpart primary linux-swap 95% -1'
 sync
 
 # otherwise e2fsck fails with "need terminal for interactive repairs"
@@ -754,6 +741,48 @@ if [[ $(imvirt) == "Physical" ]] || $PRO_EDITION ; then
   cat >> "${TARGET}/etc/fstab" << EOF
 $SWAP_PARTITION                      none           swap       sw,pri=0  0  0
 EOF
+elif $CE_EDITION ; then
+  # install self destructing init script which enables swap partition on first
+  # boot so we have swap in CE installations but don't add the initialised
+  # swap partition to our VM images (which would increase its size)
+  cat > ${TARGET}/etc/init.d/enableswap << EOF
+#!/bin/sh
+### BEGIN INIT INFO
+# Provides:          enableswap
+# Required-Start:    checkroot
+# Required-Stop:
+# Default-Start:     S
+# Default-Stop:
+# X-Interactive:     true
+# Short-Description: Enable swap partition(s) on first boot
+### END INIT INFO
+
+PATH=/sbin:/bin
+
+# hardcoded for now
+partition=/dev/sda2
+
+[ -b "\$partition" ] || exit 0
+
+if grep -q "^\${partition}.*swap" /etc/fstab ; then
+  echo "\$0 - Nothing to do as \$partition is enabled already"
+else
+  echo "\$0 - Enabling swap partition \$partition in /etc/fstab"
+  echo "# enabled on 1st boot:"         >> /etc/fstab
+  echo "\${partition} none swap sw 0 0" >> /etc/fstab
+fi
+
+echo "\$0 - Removing itself now..."
+insserv -r enableswap
+rm -f "\$0"
+
+exit 0
+# EOF
+EOF
+
+  chroot $TARGET chmod 775 /etc/init.d/enableswap
+  chroot $TARGET ln -s /etc/init.d/enableswap /etc/rcS.d/S03enableswap
+  chroot $TARGET insserv enableswap
 fi
 
 # removals: packages which debootstrap installs but d-i doesn't