#! /bin/sh -e

# grub-mkconfig helper script for lupin. Some of this is based on 10_linux,
# but with irrelevant bits removed and the rest extended to cope with
# loopback mounts.
#
# Copyright (C) 2006,2007,2008,2009  Free Software Foundation, Inc.
# Copyright (C) 2009  Canonical Ltd.
#
# GRUB is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# GRUB is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with GRUB.  If not, see <http://www.gnu.org/licenses/>.

prefix=/usr
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
. ${libdir}/grub/grub-mkconfig_lib

if [ "x${GRUB_DISTRIBUTOR}" = "x" ] ; then
  OS=GNU/Linux
else
  OS="${GRUB_DISTRIBUTOR}"
fi

case ${GRUB_DEVICE} in
  /dev/loop/*|/dev/loop[0-9])
    loop_file=`losetup ${GRUB_DEVICE} | sed -e "s/^[^(]*(\([^)]\+\)).*/\1/"`
  ;;
esac

# Is the root filesystem loop-mounted from a file on another filesystem?
if [ "x${loop_file}" = x ] || [ ! -f "${loop_file}" ]; then
  exit 0
fi
dev_mountpoint="$(awk '"'${loop_file}'" ~ "^"$2 && $2 != "/" { print $1";"$2 }' /proc/mounts | tail -n1)"
host_device="${dev_mountpoint%;*}"
host_mountpoint="${dev_mountpoint#*;}"
if [ "x${host_device}" = x ]; then
  exit 0
fi
loop_file_relative="${loop_file#$host_mountpoint}"

# Device containing the host filesystem.
host_device_uuid="`${grub_probe} --device "${host_device}" --target=fs_uuid 2> /dev/null`" || true

if [ "x${host_device_uuid}" = "x" ] || [ "x${GRUB_DISABLE_LINUX_UUID}" = "xtrue" ] \
    || ! test -e "/dev/disk/by-uuid/${host_device_uuid}" \
    || [ "`${grub_probe} -t abstraction --device ${host_device} | sed -e 's,.*\(lvm\).*,\1,'`" = "lvm"  ] ; then
  LINUX_HOST_DEVICE=${host_device}
else
  LINUX_HOST_DEVICE=UUID=${host_device_uuid}
fi

# add crashkernel option if we have the required tools
if [ -x "/usr/bin/makedumpfile" ] && [ -x "/sbin/kexec" ]; then
    GRUB_CMDLINE_EXTRA="$GRUB_CMDLINE_EXTRA crashkernel=384M-2G:64M,2G-:128M"
fi

lupin_entry ()
{
  cat << EOF
menuentry "$1" {
EOF
  save_default_entry | sed -e "s/^/\t/"
  prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/\t/"

  cat << EOF
	linux ${rel_dirname}/${basename} root=${LINUX_HOST_DEVICE} loop=${loop_file_relative} ro $2
	initrd ${rel_dirname}/${initrd}
EOF
  cat << EOF
}
EOF
}

list=`for i in /boot/vmlinu[xz]-* /vmlinu[xz]-* ; do
        if grub_file_is_not_garbage "$i" ; then echo -n "$i " ; fi
      done`

while [ "x$list" != "x" ] ; do
  linux=`version_find_latest $list`
  echo "Found linux image: $linux" >&2
  basename=`basename $linux`
  dirname=`dirname $linux`
  rel_dirname=`make_system_path_relative_to_its_root $dirname`
  version=`echo $basename | sed -e "s,^[^0-9]*-,,g"`
  alt_version=`echo $version | sed -e "s,\.old$,,g"`
  linux_root_device_thisversion="${LINUX_ROOT_DEVICE}"

  initrd=
  for i in "initrd.img-${version}" "initrd-${version}.img" \
	   "initrd-${version}" "initrd.img-${alt_version}" \
	   "initrd-${alt_version}.img" "initrd-${alt_version}"; do
    if test -e "${dirname}/${i}" ; then
      initrd="$i"
      break
    fi
  done
  if test -n "${initrd}" ; then
    echo "Found initrd image: ${dirname}/${initrd}" >&2
  else
    # None of this can work without an initrd, so don't even bother.
    list=`echo $list | tr ' ' '\n' | grep -vx $linux | tr '\n' ' '`
    continue
  fi

  lupin_entry "${OS}, Linux ${version}" \
      "${GRUB_CMDLINE_LINUX} ${GRUB_CMDLINE_EXTRA} ${GRUB_CMDLINE_LINUX_DEFAULT}" \
      quiet
  if [ "x${GRUB_DISABLE_LINUX_RECOVERY}" != "xtrue" ]; then
    lupin_entry "${OS}, Linux ${version} (recovery mode)" \
	"single ${GRUB_CMDLINE_LINUX}"
  fi

  list=`echo $list | tr ' ' '\n' | grep -vx $linux | tr '\n' ' '`
done