#!/bin/sh

set -e
set -x

RAMDISK_DEVICE=/dev/ram0
RAMDISK_PATH=/ram0

do_mount() {
    mount $RAMDISK_DEVICE $RAMDISK_PATH
}

do_umount() {
    umount $RAMDISK_DEVICE
}

do_snapshot() {
    do_umount
    snapshot $RAMDISK_DEVICE
    do_mount
}

do_rollback() {
    do_umount
    rollback $RAMDISK_DEVICE
    do_mount
}

test -b $RAMDISK_DEVICE
test -d $RAMDISK_PATH
do_mount

touch $RAMDISK_PATH/test1
test -e $RAMDISK_PATH/test1

do_snapshot

test -e $RAMDISK_PATH/test1
touch $RAMDISK_PATH/test2
test -e $RAMDISK_PATH/test2

do_rollback

test -e $RAMDISK_PATH/test1
test ! -e $RAMDISK_PATH/test2

do_snapshot

test -e $RAMDISK_PATH/test1
test ! -e $RAMDISK_PATH/test2

do_rollback

test -e $RAMDISK_PATH/test1
test ! -e $RAMDISK_PATH/test2

do_umount