#! /bin/sh -e

# Generate grub.cfg by inspecting /boot contents.
# Copyright (C) 2006,2007,2008,2009 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/>.

transform="@program_transform_name@"

prefix=@prefix@
exec_prefix=@exec_prefix@
sbindir=@sbindir@
libdir=@libdir@
sysconfdir=@sysconfdir@
package_version=@PACKAGE_VERSION@
datarootdir=@datarootdir@
datadir=@datadir@
pkgdatadir=${datadir}/`echo @PACKAGE_TARNAME@ | sed "${transform}"`
grub_prefix=`echo /boot/grub | sed ${transform}`
grub_cfg=""
grub_mkconfig_dir=${sysconfdir}/grub.d

grub_mkdevicemap=${sbindir}/`echo grub-mkdevicemap | sed ${transform}`
grub_probe=${sbindir}/`echo grub-probe | sed ${transform}`

# Usage: usage
# Print the usage.
usage () {
    cat <<EOF
Usage: $0 [OPTION]
Generate a grub config file

  -o, --output=FILE       output generated config to FILE [default=stdout]
  -h, --help              print this message and exit
  -v, --version           print the version information and exit

Report bugs to <bug-grub@gnu.org>.
EOF
}

# Check the arguments.
for option in "$@"; do
    case "$option" in
    -h | --help)
	usage
	exit 0 ;;
    -v | --version)
	echo "$0 (GNU GRUB ${package_version})"
	exit 0 ;;
    -o)
	shift
	grub_cfg=$1
	;;
    --output=*)
	grub_cfg=`echo "$option" | sed 's/--output=//'`
	;;
    -*)
	echo "Unrecognized option \`$option'" 1>&2
	usage
	exit 1
	;;
    esac
done

. ${libdir}/grub/grub-mkconfig_lib

if [ "x$EUID" = "x" ] ; then
  EUID=`id -u`
fi

if [ "$EUID" != 0 ] ; then
  root=f
  case "`uname 2>/dev/null`" in
    CYGWIN*)
      # Cygwin: Assume root if member of admin group
      for g in `id -G 2>/dev/null` ; do
	case $g in
	  0|544) root=t ;;
	esac
      done ;;
  esac
  if [ $root != t ] ; then
    echo "$0: You must run this as root" >&2
    exit 1
  fi
fi

set $grub_mkdevicemap dummy
if test -f "$1"; then
    :
else
    echo "$1: Not found." 1>&2
    exit 1
fi

set $grub_probe dummy
if test -f "$1"; then
    :
else
    echo "$1: Not found." 1>&2
    exit 1
fi

mkdir -p ${grub_prefix}

if test -e ${grub_prefix}/device.map ; then : ; else
  ${grub_mkdevicemap}
fi

# Device containing our userland.  Typically used for root= parameter.
GRUB_DEVICE="`${grub_probe} --target=device /`"
GRUB_DEVICE_UUID="`${grub_probe} --device ${GRUB_DEVICE} --target=fs_uuid 2> /dev/null`" || true

# Device containing our /boot partition.  Usually the same as GRUB_DEVICE.
GRUB_DEVICE_BOOT="`${grub_probe} --target=device /boot`"
GRUB_DEVICE_BOOT_UUID="`${grub_probe} --device ${GRUB_DEVICE_BOOT} --target=fs_uuid 2> /dev/null`" || true

# Filesystem for the device containing our userland.  Used for stuff like
# choosing Hurd filesystem module.
GRUB_FS="`${grub_probe} --target=fs / 2> /dev/null || echo unknown`"

if test -f ${sysconfdir}/default/grub ; then
  . ${sysconfdir}/default/grub
fi

# XXX: should this be deprecated at some point?
if [ "x${GRUB_TERMINAL}" != "x" ] ; then
  GRUB_TERMINAL_INPUT="${GRUB_TERMINAL}"
  GRUB_TERMINAL_OUTPUT="${GRUB_TERMINAL}"
fi

case x${GRUB_TERMINAL_OUTPUT} in
  x | xgfxterm)
    # If this platform supports gfxterm, try to use it.
    if test -e ${grub_prefix}/gfxterm.mod ; then
      # FIXME: this should do something smarter than just loading first
      # video backend.
      GRUB_VIDEO_BACKEND=$(head -n 1 ${grub_prefix}/video.lst || true)
      if [ -n "${GRUB_VIDEO_BACKEND}" ] ; then
        GRUB_TERMINAL_OUTPUT=gfxterm
      elif [ "${GRUB_TERMINAL_OUTPUT}" = "gfxterm" ] ; then
        echo "No suitable backend could be found for gfxterm." >&2 ; exit 1
      fi
    fi
  ;;
  xconsole | xserial | xofconsole) ;;
  *) echo "Invalid output terminal \"${GRUB_TERMINAL_OUTPUT}\"" >&2 ; exit 1 ;;
esac

# check for terminals that require fonts
case ${GRUB_TERMINAL_OUTPUT} in
  gfxterm)
    if [ -n "$GRUB_FONT" ] ; then
      if is_path_readable_by_grub ${GRUB_FONT} > /dev/null ; then
        GRUB_FONT_PATH=${GRUB_FONT}
	else
	  echo "No such font or not readable by grub: ${GRUB_FONT}" >&2
	  exit 1
	fi
    else
      for dir in ${pkgdatadir} /boot/grub /usr/share/grub ; do
        for basename in unicode unifont ascii; do
	  path="${dir}/${basename}.pf2"
          if is_path_readable_by_grub ${path} > /dev/null ; then
	    GRUB_FONT_PATH=${path}
	  else
	    continue
	  fi
	  if [ "${basename}" = "ascii" ] ; then
	    # make sure all our children behave in conformance with ascii..
	    export LANG=C
	  fi
	  break 2
        done
      done
    fi
    if [ -z "${GRUB_FONT_PATH}" ] ; then
      # fallback to the native terminal for this platform
      unset GRUB_TERMINAL_OUTPUT
    fi
  ;;
  *)
    # make sure all our children behave in conformance with ascii..
    export LANG=C
esac

# These are defined in this script, export them here so that user can
# override them.
export GRUB_DEVICE \
  GRUB_DEVICE_UUID \
  GRUB_DEVICE_BOOT \
  GRUB_DEVICE_BOOT_UUID \
  GRUB_FS \
  GRUB_FONT_PATH \
  GRUB_PRELOAD_MODULES \
  GRUB_VIDEO_BACKEND

# These are optional, user-defined variables.
export GRUB_DEFAULT \
  GRUB_HIDDEN_TIMEOUT \
  GRUB_HIDDEN_TIMEOUT_QUIET \
  GRUB_TIMEOUT \
  GRUB_DISTRIBUTOR \
  GRUB_CMDLINE_LINUX \
  GRUB_CMDLINE_LINUX_DEFAULT \
  GRUB_TERMINAL_INPUT \
  GRUB_TERMINAL_OUTPUT \
  GRUB_SERIAL_COMMAND \
  GRUB_DISABLE_LINUX_UUID \
  GRUB_DISABLE_LINUX_RECOVERY \
  GRUB_GFXMODE \
  GRUB_THEME \
  GRUB_DISABLE_OS_PROBER

if test "x${grub_cfg}" != "x"; then
  rm -f ${grub_cfg}.new
  exec > ${grub_cfg}.new

  # Allow this to fail, since /boot/grub/ might need to be fatfs to support some
  # firmware implementations (e.g. OFW or EFI).
  chmod 400 ${grub_cfg}.new || grub_warn "Could not make ${grub_cfg}.new readable by only root.\
  This means that if the generated config contains a password it is readable by everyone"
fi
echo "Generating grub.cfg ..." >&2

cat << EOF
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by $0 using templates
# from ${grub_mkconfig_dir} and settings from ${sysconfdir}/default/grub
#
EOF

for i in ${grub_mkconfig_dir}/* ; do
  case "$i" in
    # emacsen backup files. FIXME: support other editors
    *~) ;;
    *)
      if grub_file_is_not_garbage "$i" && test -x "$i" ; then
        echo
        echo "### BEGIN $i ###"
        "$i"
        echo "### END $i ###"
      fi
    ;;
  esac
done

if test "x${grub_cfg}" != "x" ; then
  # none of the children aborted with error, install the new grub.cfg
  mv -f ${grub_cfg}.new ${grub_cfg}
fi

echo "done" >&2