#!/bin/sh

_root="$(dirname "${0}")"; . "${_root}/lib/env.sh"

want root log

min_ufs_pad=1024

pebkac(){
  [ "${*}" ] && echo "${*}"
  echo ""
  echo "Usage: genufs [-h] [-l <label>] [-p <pad kilobytes>] [-s <size kilobytes>] [-o <image>] <directory>"
  echo ""
  echo "Generate a UFS filesystem image populated with the files"
  echo " in the specified directory node."
  exit 1
}

while getopts "o:hl:l:p:s:" opt
do
  case "${opt}" in
    o) root_img="${OPTARG}" ;;
    l) root_name="${OPTARG}" ;;
    p) ufs_pad="${OPTARG}" ;;
    s) kbytes="${OPTARG}" ;;
    h) pebkac ;;
    [?]) pebkac "Unrecognized option ${opt}" ;;
  esac
done
shift $(( $OPTIND - 1 ))

root_src="${1}"

ufs_pad="${ufs_pad:-${min_ufs_pad}}"
root_name="${root_name:-$(basename "${root_src}")}" # "
root_img="${root_img:-${root_name}.img}"
fs_kbytes="$(( $( du -sk "${root_src}" | awk '{print $1}' ) + ${ufs_pad} ))" 2>/dev/null
kbytes="${kbytes:-${fs_kbytes}}"

# Execution constraints
[ ! -d "${root_src}" ] && err "${root_src}": not a directory
[ -f "${root_img}" ] && err "${root_img}": file exists
[ "${ufs_pad}" -lt "${min_ufs_pad}" ] && err ufs_pad should be at least "${min_ufs_pad}"
[ "${kbytes}" -lt "${fs_kbytes}" ] && err Image size "${kbytes}"kB cannot hold supplied filetree "${fs_kbytes}"kB

log Generating ufs image "${root_name}" "(${kbytes}kB)"

# Prepare the backing store
rm -f "${root_img}"
dd if=/dev/zero of="${root_img}" bs=1024 count=0 seek=${kbytes} 2> /dev/null

# Generate and mount the image
temp_root="$(mktemp -d "/tmp/${root_name}.XXXXXXXX")"
mdmfs -F "${root_img}" -U -m0 -Ospace -oasync md "${temp_root}"
temp_node="$(df "${temp_root}" | tail -n 1 | awk '{print $1}' | sed -e 's/^\/dev\///g')"

# Clean up if things explode
trap "umount -f '${temp_root}'; mdconfig -d -u '${temp_node}'; rm -Rf '${temp_root}'" exit hup int term kill

# Copy files into image
df -h "${temp_root}"
( cd "${root_src}"; find . | cpio --make-directories -p "${temp_root}" 2>&1 | egrep -v ' blocks$' )
df -h "${temp_root}" | tail -n 1
sync

# Clean up
umount -f "${temp_root}"
mdconfig -d -u "${temp_node}"
rm -Rf "${temp_root}"
trap "" exit hup int term kill

# Label the image
tunefs -L "${root_name}" "${root_img}"