grub2/grub2-snapper-plugin.sh

#!/bin/sh
set -e

# Copyright (C) 2006,2007,2008,2009,2010  Free Software Foundation, Inc.
#
# 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/>.

grub_mkconfig="/usr/sbin/grub2-mkconfig"
grub_mkrelpath="/usr/bin/grub2-mkrelpath"
grub_script_check="/usr/bin/grub2-script-check"
grub_setting="/etc/default/grub"
grub_cfg="/boot/grub2/grub.cfg"
grub_snapshot_cfg="/boot/grub2/snapshot_submenu.cfg"

snapper_snapshot_path="/.snapshots"
snapshot_submenu_name="snapshot_submenu.cfg"
snapper_snapshots_cfg="${snapper_snapshot_path}/snapshot_submenu.cfg"

case x"`uname -m`" in
  x"powerpc"* | x"ppc"*)
    target="powerpc-ieee1275";;
  x"sparc"*)
    target="sparc64-ieee1275";;
  x"mips"*"el")
    target="mipsel-loongson";;
  x"mips"*)
    target="mips-arc";;
  x"ia64"*)
    target="ia64-efi";;
  x"x86_64"* | x"amd64"*)
    modprobe -q efivars 2>/dev/null || true
    if [ -d /sys/firmware/efi ]; then
      target="x86_64-efi"
    else
      target=i386-pc
    fi
  ;;
  x"i"?"86"*)
    modprobe -q efivars 2>/dev/null || true 
    if [ -d /sys/firmware/efi ]; then
      target="i386-efi"
    elif [ -e /proc/device-tree ]; then
      target=i386-pc
      for x in /proc/device-tree/*; do
        if [ -e "$x" ]; then
          target="i386-ieee1275"
        fi
      done
    else
      target=i386-pc
    fi
  ;;
  *)
    target=""
  ;;
esac

if [ "x${target}" != "xi386-pc" ] && 
   [ "x${target}" != "xx86_64-efi" ] &&
   [ "x${target}" != "xi386-efi" ]; then
  exit 0;
fi

snapshot_submenu_refresh () {

for s_dir in ${snapper_snapshot_path}/*; do

  snapshot="${s_dir}/snapshot"
  snapper_cfg="${s_dir}/${snapshot_submenu_name}"
  num="`basename $s_dir`"
  
  if [ ! -d "$snapshot" ]; then
    rm -f "${snapper_cfg}"
    rmdir "$s_dir" 2>/dev/null || true
    continue
  fi

  # bnc#864842 Important snapshots are not marked as such in grub2 menu
  # the format is "important distribution version (kernel_version, timestamp, pre/post)"
  date=`xmllint --xpath '/snapshot/date/text()' "${s_dir}/info.xml" || echo ""`
  date=`echo $date | sed 's/\(.*\) \(.*\):.*/\1,\2/'`
  important=`xmllint --xpath "/snapshot/userdata[key='important']/value/text()" "${s_dir}/info.xml" || echo ""`
  stype=`xmllint --xpath '/snapshot/type/text()' "${s_dir}/info.xml" || echo ""`
  kernel_ver=`readlink /boot/vmlinuz | sed 's/vmlinuz-\([^-]*\).*/\1/'`
  eval `cat ${snapshot}/etc/os-release` 
  test "$important" = "yes" && important="*" || important=""
  test "$stype" = "single" && stype=""

  if test -n "$stype"; then
    title="${important}${NAME} $VERSION ($kernel_ver,$date,$stype)"
  else
    title="${important}${NAME} $VERSION ($kernel_ver,$date)"
  fi

  cat <<EOF > "${snapper_cfg}.new"

  if [ -f "${snapper_snapshot_path}/$num/snapshot/boot/grub2/grub.cfg" ]; then
    snapshot_found=true
    saved_subvol=\$btrfs_subvol
      menuentry "$title" "${snapper_snapshot_path}/$num/snapshot" "`$grub_mkrelpath ${snapper_snapshot_path}/${num}/snapshot`" {
        btrfs_subvol="\$2"
        extra_cmdline="rootflags=subvol=\$3"
        configfile /boot/grub2/grub.cfg
        btrfs_subvol=\$saved_subvol
      }
  fi

EOF
 
  if ${grub_script_check} "${snapper_cfg}.new"; then
    mv -f "${snapper_cfg}.new" "${snapper_cfg}"
  fi

done

}

snapper_snapshots_cfg_refresh () {

  if [ ! -d "$snapper_snapshot_path" ]; then
    return
  fi

  for s_dir in ${snapper_snapshot_path}/*; do

    snapshot="${s_dir}/snapshot"
    snapper_cfg="${s_dir}/${snapshot_submenu_name}"

    if [ -f "${snapper_cfg}" ]; then
      cs="${s_dir}\n${cs}"
      continue
    fi

  done

  for c in `echo -e "${cs}" | sort -V`; do
    snapshot_cfg="\
  if [ -f "$c/snapshot_submenu.cfg" ]; then
    source "$c/snapshot_submenu.cfg"
  fi
${snapshot_cfg}"
  done

  cat <<EOF >"${snapper_snapshots_cfg}.new"
submenu "Bootable snapshots" { 
${snapshot_cfg}
  if [ x\$snapshot_found != xtrue ]; then
	submenu "Not Found" {true}
  fi
}
EOF

  if ${grub_script_check} "${snapper_snapshots_cfg}.new"; then
    mv -f "${snapper_snapshots_cfg}.new" "${snapper_snapshots_cfg}"
  fi

}


snapshot_submenu_clean () {

  for s_dir in ${snapper_snapshot_path}/*; do

    snapper_cfg="${s_dir}/${snapshot_submenu_name}"

    if [ -f "$snapper_cfg" ]; then
      rm -f "$snapper_cfg"
      rmdir "$s_dir" 2>/dev/null || true
    fi

  done

  if [ -f "${snapper_snapshot_path}/${snapshot_submenu_name}" ]; then
    rm -f "${snapper_snapshot_path}/${snapshot_submenu_name}"
  fi

}

set_grub_setting () {

  name=$1
  val=$2

  if grep -q "$name" "$grub_setting"; then
    sed -i -e "s!.*\($name\)=.*!\1=\"$val\"!" "$grub_setting"
  else
    echo "$name=\"$val\"" >> "$grub_setting"
  fi
}

enable_grub_settings () {
  set_grub_setting SUSE_BTRFS_SNAPSHOT_BOOTING "true"
}

disable_grub_settings () {
  set_grub_setting SUSE_BTRFS_SNAPSHOT_BOOTING "false"
}

update_grub () {
   "${grub_mkconfig}" -o "${grub_cfg}"
}

# Check the arguments.
while test $# -gt 0
do
  option=$1
  shift

  case "$option" in
  -e | --enable)
  opt_enable=true
  ;;
  -d | --disable)
  opt_enable=false
  ;;
  -r | --refresh)
  opt_refresh=true
  ;;
  -c | --clean)
  opt_clean=true
  ;;
  -*)
  ;;
  esac
done

if [ "x${opt_enable}" = "xtrue" ]; then
  #enable_grub_settings
  #update_grub
  snapshot_submenu_refresh
  snapper_snapshots_cfg_refresh
elif [ "x${opt_enable}" = "xfalse" ]; then
  #disable_grub_settings
  update_grub
  snapshot_submenu_clean
fi

if [ x${opt_refresh} = "xtrue" ]; then
  snapshot_submenu_refresh
  snapper_snapshots_cfg_refresh
fi

if [ x${opt_clean} = "xtrue" ]; then
  snapshot_submenu_clean
fi