#!/bin/sh
set -e

# Generate grub.cfg by inspecting /boot contents.
# 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/>.

prefix="/usr"
exec_prefix="/usr"
datarootdir="/usr/share"

prefix="/usr"
exec_prefix="/usr"
sbindir="/sbin"
bindir="${exec_prefix}/bin"
sysconfdir="/etc"
PACKAGE_NAME=GRUB
PACKAGE_VERSION=2.06
host_os=linux-gnu
datadir="${datarootdir}"
if [ "x$pkgdatadir" = x ]; then
    pkgdatadir="${datadir}/grub"
fi
# export it for scripts
export pkgdatadir

grub_cfg=""
grub_mkconfig_dir="${sysconfdir}"/grub.d

self=`basename $0`

grub_probe="${sbindir}/grub2-probe"
grub_file="${bindir}/grub2-file"
grub_editenv="${bindir}/grub2-editenv"
grub_script_check="${bindir}/grub2-script-check"

export TEXTDOMAIN=grub
export TEXTDOMAINDIR="${datarootdir}/locale"

. "${pkgdatadir}/grub-mkconfig_lib"

# Usage: usage
# Print the usage.
usage () {
    gettext_printf "Usage: %s [OPTION]\n" "$self"
    gettext_printf "Generate a grub config file\n\n"

    print_option_help "-o, --output=$(gettext FILE)" "$(gettext "output generated config to FILE [default=stdout]")"
    print_option_help "-p, --photoncfg=$(gettext FILE)" "$(gettext "Generate Photon specific config to FILE [default=stdout]")"
    print_option_help "-y" "$(gettext "Don't prompt for making changes and proceed")"
    print_option_help "-h, --help" "$(gettext "print this message and exit")"
    print_option_help "-V, --version" "$(gettext "print the version information and exit")"

    gettext_printf "\nReport bugs to <bug-grub@gnu.org>\n"
}

ShowWarningBanner() {
  local pound_line="#######################"
  gettext_printf "\n${pound_line}${pound_line}\n"
  gettext_printf " Photon OS uses it's own customized grub.cfg\n"
  gettext_printf "    *** PROCEED WITH CAUTION ***\n\n"
  usage
  gettext_printf "${pound_line}${pound_line}\n\n"
}

ShowWarningBanner

argument () {
  opt=$1
  shift

  if test $# -eq 0; then
      gettext_printf "%s: option requires an argument -- \`%s'\n" "$self" "$opt" 1>&2
      exit 1
  fi
  echo $1
}

isPhotonCfg=0
ShowWarning=1

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

    case "$option" in
    -h | --help)
       # we are showing help in warning banner
	exit 0 ;;
    -V | --version)
	echo "$self (${PACKAGE_NAME}) ${PACKAGE_VERSION}"
	exit 0 ;;
    -o | --output)
       grub_cfg=$(argument $option "$@"); isPhotonCfg=0; shift;;
    -p | --photoncfg)
       grub_cfg=$(argument $option "$@"); isPhotonCfg=1; shift;;
    -y) ShowWarning=0;;
    --output=*)
	grub_cfg=`echo "$option" | sed 's/--output=//'`
	;;
    -*)
	gettext_printf "Unrecognized option \`%s'\n" "$option" 1>&2
	usage
	exit 1
	;;
    # Explicitly ignore non-option arguments, for compatibility.
    esac
done

# for accidental usage of grub2-mkconfig -p -y
if [ "$grub_cfg" = "-y" ]; then
  gettext_printf "Invalid output file name: $grub_cfg" 1>&2
  exit 1
fi

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 [ $root != t ] ; then
    gettext_printf "%s: You must run this as root\n" "$self" >&2
    exit 1
  fi
fi

PromptUsr() {
  local opt="n"
  local PromptMsg="$1"

  gettext_printf "${PromptMsg}\n"

  while [ "${opt}" != "y" ]; do
    read -p "Are you sure you want to continue [y/n]? " opt
    case ${opt} in
      [y] ) : break;;
      [n] ) exit 1;;
      * ) gettext_printf "Please answer y or n";;
    esac
  done
}

if [ $ShowWarning = 1 ]; then
  if [ $isPhotonCfg = 1 ]; then
    PromptUsr "This will modify grub.cfg in Photon OS specific way."
  else
    gettext_printf "\nThis will modify grub.cfg with default method. Photon specific changes will be overwritten.\n"
  fi
fi

# This function takes a copy of existing grub.cfg
# then modifies it as needed
HandlePhotonGrubCfg() {
  local i
  local oldmask

  # For security reasons, maintain proper umask
  if test "x${grub_cfg}" != "x"; then
    rm -f "${grub_cfg}.new"
    oldumask=$(umask); umask 077
    # redirecting stdout to ${grub_cfg}.new here, cool idea
    exec > "${grub_cfg}.new"
    umask $oldumask
  fi

  gettext_printf "Generating grub configuration file ...\n" >&2

  # get content of existing grub.cfg
  cat /boot/grub2/grub.cfg > "${grub_cfg}.new"
  sed '$d' "${grub_cfg}.new"

  for i in "${grub_mkconfig_dir}"/* ; do
    # let's process only 01_users & 40_custom
    # we can add other files on demand basis
    if [ $i != "${grub_mkconfig_dir}/01_users" ] && \
       [ $i != "${grub_mkconfig_dir}/40_custom" ]; then
          continue
    fi
    case "$i" in
      *~) ;;
      */\#*\#) ;;
      *)
        if grub_file_is_not_garbage "$i" && test -x "$i" ; then
          echo -e "\n### BEGIN $i ###\n"
          "$i"
          echo "### END $i ###"
        fi
        ;;
    esac
  done

  if test "x${grub_cfg}" != "x" ; then
    if ! ${grub_script_check} ${grub_cfg}.new; then
      gettext_printf "Syntax errors are detected in generated GRUB config file.
      Ensure that there are no errors in /etc/grub.d/* files
      or please file a bug report with %s file attached.\n" "${grub_cfg}.new" >&2
      exit 1
    else
      # none of the children aborted with error, install the new grub.cfg
      gettext_printf "\n\n# End /boot/grub2/grub.cfg" >> "${grub_cfg}.new"
      cat ${grub_cfg}.new > ${grub_cfg}
      rm -f ${grub_cfg}.new
    fi
  fi

  gettext_printf "done\n" >&2
}

if [ $isPhotonCfg = 1 ]; then
  HandlePhotonGrubCfg
  exit 0
fi

# Backup default photon grub.cfg
if [ "$(realpath $grub_cfg)" = "/boot/grub2/grub.cfg" ]; then
  if [ ! -f /boot/grub2/photon-grub.cfg ]; then
    if [ -f /boot/grub2/grub.cfg ]; then
      echo "Taking backup of /boot/grub2/grub.cfg as /boot/grub2/photon-grub.cfg"
      # Preserve original file permissions
      cp -p /boot/grub2/grub.cfg /boot/grub2/photon-grub.cfg
    fi
  else
    echo "Backup file /boot/grub2/photon-grub.cfg already exists"
  fi
fi

set $grub_probe dummy
if test -f "$1"; then
    :
else
    gettext_printf "%s: Not found.\n" "$1" 1>&2
    exit 1
fi

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

# Disable os-prober by default due to security reasons.
GRUB_DISABLE_OS_PROBER="true"

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

if [ x"$GRUB_FS" = xunknown ]; then
    GRUB_FS="$(stat -f -c %T / || echo unknown)"
fi

# Provide a default set of stock linux early initrd images.
# Define here so the list can be modified in the sourced config file.
if [ "x${GRUB_EARLY_INITRD_LINUX_STOCK}" = "x" ]; then
	GRUB_EARLY_INITRD_LINUX_STOCK="intel-uc.img intel-ucode.img amd-uc.img amd-ucode.img early_ucode.cpio microcode.cpio"
fi

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

if [ "x${GRUB_DISABLE_UUID}" = "xtrue" ]; then
  if [ -z "${GRUB_DISABLE_LINUX_UUID}" ]; then
    GRUB_DISABLE_LINUX_UUID="true"
  fi
  if [ -z "${GRUB_DISABLE_LINUX_PARTUUID}" ]; then
    GRUB_DISABLE_LINUX_PARTUUID="true"
  fi
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

termoutdefault=0
if [ "x${GRUB_TERMINAL_OUTPUT}" = "x" ]; then
    GRUB_TERMINAL_OUTPUT=gfxterm;
    termoutdefault=1;
fi

for x in ${GRUB_TERMINAL_OUTPUT}; do
    case "x${x}" in
	xgfxterm) ;;
	xconsole | xserial | xofconsole | xvga_text)
            # make sure all our children behave in conformance with ascii..
	    export LANG=C;;
	*) echo "Invalid output terminal \"${GRUB_TERMINAL_OUTPUT}\"" >&2 ; exit 1 ;;
    esac
done

GRUB_ACTUAL_DEFAULT="$GRUB_DEFAULT"

if [ "x${GRUB_ACTUAL_DEFAULT}" = "xsaved" ] ; then GRUB_ACTUAL_DEFAULT="`"${grub_editenv}" - list | sed -n '/^saved_entry=/ s,^saved_entry=,,p'`" ; fi


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

# These are optional, user-defined variables.
export GRUB_DEFAULT \
  GRUB_HIDDEN_TIMEOUT \
  GRUB_HIDDEN_TIMEOUT_QUIET \
  GRUB_TIMEOUT \
  GRUB_TIMEOUT_STYLE \
  GRUB_DEFAULT_BUTTON \
  GRUB_HIDDEN_TIMEOUT_BUTTON \
  GRUB_TIMEOUT_BUTTON \
  GRUB_TIMEOUT_STYLE_BUTTON \
  GRUB_BUTTON_CMOS_ADDRESS \
  GRUB_BUTTON_CMOS_CLEAN \
  GRUB_DISTRIBUTOR \
  GRUB_CMDLINE_LINUX \
  GRUB_CMDLINE_LINUX_DEFAULT \
  GRUB_CMDLINE_XEN \
  GRUB_CMDLINE_XEN_DEFAULT \
  GRUB_CMDLINE_LINUX_XEN_REPLACE \
  GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT \
  GRUB_CMDLINE_NETBSD \
  GRUB_CMDLINE_NETBSD_DEFAULT \
  GRUB_CMDLINE_GNUMACH \
  GRUB_EARLY_INITRD_LINUX_CUSTOM \
  GRUB_EARLY_INITRD_LINUX_STOCK \
  GRUB_TERMINAL_INPUT \
  GRUB_TERMINAL_OUTPUT \
  GRUB_SERIAL_COMMAND \
  GRUB_DISABLE_UUID \
  GRUB_DISABLE_LINUX_UUID \
  GRUB_DISABLE_LINUX_PARTUUID \
  GRUB_DISABLE_RECOVERY \
  GRUB_VIDEO_BACKEND \
  GRUB_GFXMODE \
  GRUB_BACKGROUND \
  GRUB_THEME \
  GRUB_GFXPAYLOAD_LINUX \
  GRUB_INIT_TUNE \
  GRUB_SAVEDEFAULT \
  GRUB_ENABLE_CRYPTODISK \
  GRUB_BADRAM \
  GRUB_OS_PROBER_SKIP_LIST \
  GRUB_DISABLE_SUBMENU

if test "x${grub_cfg}" != "x"; then
  rm -f "${grub_cfg}.new"
  oldumask=$(umask); umask 077
  exec > "${grub_cfg}.new"
  umask $oldumask
fi
gettext "Generating grub configuration file ..." >&2
echo >&2

cat << EOF
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by $self 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
    *~) ;;
    # emacsen autosave 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
  if ! ${grub_script_check} ${grub_cfg}.new; then
    # TRANSLATORS: %s is replaced by filename
    gettext_printf "Syntax errors are detected in generated GRUB config file.
Ensure that there are no errors in /etc/default/grub
and /etc/grub.d/* files or please file a bug report with
%s file attached." "${grub_cfg}.new" >&2
    echo >&2
    exit 1
  else
    # none of the children aborted with error, install the new grub.cfg
    cat ${grub_cfg}.new > ${grub_cfg}
    rm -f ${grub_cfg}.new
  fi
fi

gettext "done" >&2
echo >&2
