#!/bin/bash
#
# Insert a list of installed kernels in a grub config file
#   Copyright 2001 Wichert Akkerman <wichert@linux.com>
#   Copyright (C) 2007,2008  Free Software Foundation, Inc.
#
# This file 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.
#
# This program 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/>.
#
# Contributors:
#	Jason Thomas <jason@debian.org>
#	David B.Harris <dbarclay10@yahoo.ca>
#	Marc Haber <mh+debian-packages@zugschlus.de>
#	Crispin Flowerday <crispin@zeus.com>

# Abort on errors
set -e

host_os=`uname -s | tr '[A-Z]' '[a-z]'`

abort() {
	message=$@

	echo >&2
	echo -e "$message" >&2
	echo >&2
	exit 1
}

find_grub_dir ()
{
	echo  -n "Searching for GRUB installation directory ... " >&2

	for d in /boot/grub /boot/boot/grub ; do
		if [ -d "$d" ] ; then
			grub_dir="$d"
			break
		fi
	done
	
	if [ -z "$grub_dir" ] ; then
		abort "No GRUB directory found.\n To create a template run 'mkdir /boot/grub' first.\n To install grub, install it manually or try the 'grub-install' command.\n ### Warning, grub-install is used to change your MBR. ###"
	else
		echo "found: $grub_dir" >&2
	fi

	echo $grub_dir
}

# This function was borrowed from grub2/util/update-grub_lib.in
make_system_path_relative_to_its_root ()
{
  path=$1
  # abort if file doesn't exist
  if test -e $path ; then : ;else
    return 1
  fi

  # canonicalize
  if path=`readlink -f $path` ; then : ; else
    return 1
  fi

  # if not a directory, climb up to the directory containing it
  if test -d $path ; then
    dir=$path
  else
    dir=`echo $path | sed -e "s,/[^/]*$,,g"`
  fi

  num=`stat -c %d $dir`

  # this loop sets $dir to the root directory of the filesystem we're inspecting
  while : ; do
    parent=`readlink -f $dir/..`
    if [ "x`stat -c %d $parent`" = "x$num" ] ; then : ; else
      # $parent is another filesystem; we found it.
      break
    fi
    if [ "x$dir" = "x/" ] ; then
      # / is our root.
      break
    fi
    dir=$parent
  done

  # This function never prints trailing slashes (so that its output can be
  # appended a slash unconditionally).  Each slash in $dir is considered a
  # preceding slash, and therefore the root directory is an empty string.
  if [ "$dir" = "/" ] ; then
    dir=""
  fi

  echo $path | sed -e "s,^$dir,,g"
}

# The grub installation directory
grub_dir=$(find_grub_dir)

# Full path to the device.map
device_map=$grub_dir/device.map

find_device ()
{
	if ! test -e ${device_map} ; then
		echo quit | grub --batch --no-floppy --device-map=${device_map} > /dev/null
	fi
	grub-probe --device-map=${device_map} -t device $1 2> /dev/null
}

# Usage: convert_raid1 os_device
# Checks if os_device is a software raid1.
# If so, converts to first physical device in array.
convert_raid1 ()
{
    case $1 in
        /dev/md[0-9] | /dev/md/[0-9])
            : ;; # Continue
        *)
            return 1 ;;
    esac

    [ -x /sbin/mdadm ] || return 1

    # Check that the raid device is raid1
    raidlevel=$(mdadm -D -b $1 | grep "^ARRAY" | \
            sed "s/^.*level=//" | cut -d" " -f1)
    [ "$raidlevel" = "raid1" ] || return 1
    
    # Take only the first device that makes up the raid
    raiddev=$(mdadm -D $1 | grep -A1 "Number" | grep "dev" \
                          | sed "s/^.*\(\/dev\/.*\)$/\1/")
    [ -n "$raiddev" ] || return 1

    echo $raiddev
    return 0
}

# Usage: convert os_device
# Convert an OS device to the corresponding GRUB drive.
convert () {
	if ! test -e ${device_map} ; then
		echo quit | grub --batch --no-floppy --device-map=${device_map} > /dev/null
	fi
	GRUB_LEGACY_0_BASED_PARTITIONS=1 grub-probe --device-map=${device_map} -t drive -d "$1" 2> /dev/null || { 
		echo "warning: grub-probe can't find drive for $1." >&2
		tmp_map=$(mktemp -t device.map.XXXXXXXX)
		grub-mkdevicemap --device-map=${tmp_map} --no-floppy >/dev/null 2>&1 || true
		GRUB_LEGACY_0_BASED_PARTITIONS=1 grub-probe --device-map=${tmp_map} -t drive -d "$1" || {
			rm -f ${tmp_map}
			return 1
		}
		echo "Please check ${device_map}, you might have to regenerate it with grub-mkdevicemap." >&2
		rm -f ${tmp_map}
	}
}

# Usage: convert_default os_device
# Convert an OS device to the corresponding GRUB drive.
convert_default () {
	# Check if device is software raid1 array
	if tmp_dev=$(convert_raid1 $1 2>/dev/null) ; then
		: # Use device returned by convert_raid1
	else
		tmp_dev=$1
	fi

	convert $tmp_dev
}

## Configuration Options

# Full path to the menu.lst
menu_file_basename=menu.lst
menu_file=$grub_dir/$menu_file_basename

# Full path to the default file
default_file_basename=default
default_file=$grub_dir/$default_file_basename

# the device for the / filesystem
root_device=$(find_device "/")

# loop-AES arranges things so that /dev/loop/X can be our root device, but
# the initrds that Linux uses don't like that.
case ${root_device} in
  /dev/loop/*|/dev/loop[0-9])
    root_device=`losetup ${root_device} | sed -e "s/^[^(]*(\([^)]\+\)).*/\1/"`
  ;;
esac

# the device for the /boot filesystem
boot_device=$(find_device "/boot")

# where grub looks for the kernels at boot time
kernel_dir=`make_system_path_relative_to_its_root /boot`

# the "-t abstraction" check is a workaround untill #484297 is fixed
if abstraction=`grub-probe -t abstraction --device ${root_device} 2> /dev/null` && [ "$abstraction" = "" ] && \
    root_uuid=`grub-probe --device-map=${device_map} --device ${root_device} --target=fs_uuid 2> /dev/null` && \
    test -e "/dev/disk/by-uuid/${root_uuid}" ; then
  linux_root_device=UUID=${root_uuid}
else
  linux_root_device=${root_device}
fi

# Default kernel options, overidden by the kopt statement in the menufile.
kopt="root=$linux_root_device ro"

# Title
title="Debian GNU/`uname -s | sed -e s,GNU/,,g`"

# should update-grub remember the default entry
updatedefaultentry="false"

# Drive(in GRUB terms) where the kernel is located. Overridden by the
# groot statement in menufile.
grub_root_device=$(convert_default "$boot_device")

# should grub create the alternative boot options in the menu
	alternative="true"

# should grub lock the alternative boot options in the menu
	lockalternative="false"

# additional options to use with the default boot option, but not with the
# alternatives
	defoptions=""

# should grub lock the old kernels
	lockold="false"

# Xen hypervisor options to use with the default Xen boot option
	xenhopt=""

# Xen Linux kernel options to use with the default Xen boot option
	xenkopt="console=tty0"

# options to use with the alternative boot options
	altoptions="(single-user mode) single"

# controls howmany kernels are listed in the config file,
# this does not include the alternative kernels
	howmany="all"

# should grub create a memtest86 entry
	memtest86="true"

# should grub add "savedefault" to default boot options
	savedefault="false"

# stores the command line arguments
	command_line_arguments=$1

# read user configuration
if test -f "/etc/default/grub" ; then
    . /etc/default/grub
fi

# Default options to use in a new config file. This will only be used if $menu_file
# doesn't already exist. Only edit the lines between the two "EOF"s. The others are
# part of the script.
newtemplate=$(tempfile)
cat > "$newtemplate" <<EOF
# $menu_file_basename - See: grub(8), info grub, update-grub(8)
#            grub-install(8), grub-floppy(8),
#            grub-md5-crypt, /usr/share/doc/grub
#            and /usr/share/doc/grub-legacy-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not change this entry to 'saved' or your
# array will desync and will not let you boot your system.
default		0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout		5

# Pretty colours
color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line)  and entries protected by the
# command 'lock'
# e.g. password topsecret
#      password --md5 \$1\$gLhU0/\$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title		Windows 95/98/NT/2000
# root		(hd0,0)
# makeactive
# chainloader	+1
#
# title		Linux
# root		(hd0,1)
# kernel	/vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

EOF
## End Configuration Options

echo -n "Searching for default file ... " >&2
if [ -f "$default_file" ] ; then
  echo "found: $default_file" >&2
else
  echo "Generating $default_file file and setting the default boot entry to 0" >&2
  if [ -f /usr/lib/grub-legacy/grub-set-default ] ; then
    /usr/lib/grub-legacy/grub-set-default $1
  else
    grub-set-default $1
  fi
fi

# Make sure we use the standard sorting order
LC_COLLATE=C
# Magic markers we use
start="### BEGIN AUTOMAGIC KERNELS LIST"
end="### END DEBIAN AUTOMAGIC KERNELS LIST"

startopt="## ## Start Default Options ##"
endopt="## ## End Default Options ##"

# Extract options from config file
ExtractMenuOpt()
{
	opt=$1

	sed -ne "/^$start\$/,/^$end\$/ {
		/^$startopt\$/,/^$endopt\$/ {
			/^# $opt=/ {
				s/^# $opt=\(.*\)\$/\1/
				p
			}
		}
	}" $menu
}

GetMenuOpts()
{
	opt=$1

	sed -ne "/^$start\$/,/^$end\$/ {
		/^$startopt\$/,/^$endopt\$/ {
			/^# $opt=/ {
				p
			}
		}
	}" $menu
}

ExtractMenuOpts()
{
	opt=$1

	GetMenuOpts $opt | sed "s/^# $opt=\(.*\)\$/\1=\"\2\"/"
}

GetMenuOpt()
{
	opt=$1
	value=$2

	[ -z "$(GetMenuOpts "$opt")" ] || value=$(ExtractMenuOpt "$opt")

	echo $value
}

# Compares two version strings A and B
# Returns -1 if A<B
#          0 if A==B
#          1 if A>B
# This compares version numbers of the form
# 2.4.14.2 > 2.4.14
# 2.4.14random = 2.4.14-random > 2.4.14-ac10 > 2.4.14 > 2.4.14-pre2 > 
# 2.4.14-pre1 > 2.4.13-ac99
CompareVersions()
{  
	local a=`echo $1 | sed -e "s,.*/vmlinu[zx]-,,g;s/[._-]\(pre\|rc\|test\|git\)/~\1/g"`
	local b=`echo $2 | sed -e "s,.*/vmlinu[zx]-,,g;s/[._-]\(pre\|rc\|test\|git\)/~\1/g"`
	if [ "$a" = "$b" ] ; then
		echo 0
	elif dpkg --compare-versions "$a" gt "$b" ; then
		echo 1
	else
		echo -1
	fi
}

# looks in the directory specified for an initrd image with the version specified
FindInitrdName()
{
	# strip trailing slashes
	directory=$(echo $1 | sed -e 's#/*$##')
	version=$2

	# initrd
	# initrd.img
	# initrd-lvm
	# .*.gz

	initrdName=""
	names="initrd initrd.img initrd-lvm"
	compressed="gz"

	for n in $names ; do
		# make sure we haven't already found it
		if [ -z "$initrdName" ] ; then
			if [ -f "$directory/$n$version" ] ; then
				initrdName="$n$version"
				break
			else
				for c in $compressed ; do
					if [ -f "$directory/$n$version.$c" ] ; then
						initrdName="$n$version.$c"
						break
					fi
				done
			fi
		else
			break
		fi
	done

	# return the result
	echo $initrdName
}

FindXenHypervisorVersions ()
{
	version=$1

	if [ -f "/var/lib/linux-image-$version/xen-versions" ]; then
		ret="$(cat /var/lib/linux-image-$version/xen-versions)"
	fi

	echo $ret
}

get_kernel_opt()
{
	kernel_version=$1

	version=$(echo $kernel_version | sed 's/^[^0-9]*//')
	version=$(echo $version | sed 's/[-\+\.]/_/g')
	if [ -n "$version" ] ; then
		while [ -n "$version" ] ; do
			currentOpt="$(eval "echo \${kopt_$version}")"
			if [ -n "$currentOpt" ] ; then
				break
			fi
			version=$(echo $version | sed 's/_\?[^_]*$//')
		done
	fi

	if [ -z "$currentOpt" ] ; then
			currentOpt=$kopt
	fi

	echo $currentOpt
}

write_kernel_entry()
{
	local kernel_version; kernel_version=$1; shift
	local recovery_desc; recovery_desc=$1; shift
	local lock_alternative; lock_alternative=$1; shift
	local grub_root_device; grub_root_device=$1; shift
	local kernel; kernel=$1; shift
	local kernel_options; kernel_options=$1; shift
	local recovery_suffix; recovery_suffix=$1; shift
	local initrd; initrd=$1; shift
	local savedefault; savedefault=$1; shift
	local lockold; lockold=$1; shift
	local hypervisor
	if [ -n "$1" ]; then
		# Hypervisor.
		hypervisor=$1; shift
		local hypervisor_image; hypervisor_image=$1; shift
		local hypervisor_version; hypervisor_version=$1; shift
		local hypervisor_options; hypervisor_options=$1; shift
	fi

	echo -n "title		" >> $buffer

	if [ -n "$hypervisor" ]; then
		echo -n "$hypervisor $hypervisor_version / " >> $buffer
	fi

	echo -n "$title" >> $buffer
	if [ -n "$kernel_version" ]; then
		echo -n ", kernel $kernel_version" >> $buffer
	fi
	if [ -n "$recovery_desc" ]; then
		echo -n " $recovery_desc" >> $buffer
	fi
	echo >> $buffer

	# lock the alternative options
	if test x"$lock_alternative" = x"true" ; then
		echo "lock" >> $buffer
	fi
	# lock the old entries
	if test x"$lockold" = x"true" ; then
	echo "lock" >> $buffer
	fi

	echo "root		$grub_root_device" >> $buffer

	echo -n "kernel		"  >> $buffer
	if [ -n "$hypervisor" ]; then
		echo -n "$hypervisor_image" >> $buffer
		if [ -n "$hypervisor_options" ]; then
			echo -n " $hypervisor_options"  >> $buffer
		fi
		echo >> $buffer
		echo -n "module		"  >> $buffer
	fi
	echo -n "$kernel"  >> $buffer
	if [ -n "$kernel_options" ]; then
		echo -n " $kernel_options"  >> $buffer
	fi
	if [ -n "$recovery_desc" ]; then
		echo -n " $recovery_suffix"  >> $buffer
	fi
	echo >> $buffer

	if [ -n "$initrd" ]; then
		if [ -n "$hypervisor" ]; then
			echo -n "module		" >> $buffer
		else
			echo -n "initrd		" >> $buffer
		fi
		echo "$initrd" >> $buffer
	fi

	if test x"$savedefault" = x"true" ; then
		echo "savedefault" >> $buffer
	fi
	echo >> $buffer
}


echo -n "Testing for an existing GRUB $menu_file_basename file ... " >&2

# Test if our menu file exists
if [ -f "$menu_file" ] ; then
	menu="$menu_file"
	rm -f $newtemplate
	unset newtemplate
	echo "found: $menu_file" >&2
	cp -f "$menu_file" "$menu_file~"
else
	# if not ask user if they want us to create one
	menu="$menu_file"
	echo >&2
	echo >&2
	if [ "-y" = "$command_line_arguments" ] ; then
		echo "Warning: ignoring deprecated -y option." >&2
	fi
	echo >&2
	echo "Generating $menu_file" >&2
	cat "$newtemplate" > $menu_file
	rm -f $newtemplate
	unset newtemplate
fi

# Extract the kernel options to use
kopt=$(GetMenuOpt "kopt" "$kopt")

# Set the kernel 2.6 option only for fresh install
test -z "$(GetMenuOpt "kopt" "")" && kopt_2_6="root=$linux_root_device ro"

# Extract options for specific kernels
opts="$(ExtractMenuOpts "\(kopt_[[:alnum:]_]\+\)")"
test -z "$opts" || eval "$opts"
CustomKopts=$(GetMenuOpts "\(kopt_[[:alnum:]_]\+\)")

# Extract the grub root
grub_root_device=$(GetMenuOpt "groot" "$grub_root_device")

# Extract the old recovery value
alternative=$(GetMenuOpt "recovery" "$alternative")

# Extract the alternative value
alternative=$(GetMenuOpt "alternative" "$alternative")

# Extract the lockalternative value
lockalternative=$(GetMenuOpt "lockalternative" "$lockalternative")

# Extract the additional default options
defoptions=$(GetMenuOpt "defoptions" "$defoptions")

# Extract the lockold value
lockold=$(GetMenuOpt "lockold" "$lockold")

# Extract Xen hypervisor options
xenhopt=$(GetMenuOpt "xenhopt" "$xenhopt")

# Extract Xen Linux kernel options
xenkopt=$(GetMenuOpt "xenkopt" "$xenkopt")

# Extract the howmany value
howmany=$(GetMenuOpt "howmany" "$howmany")

# Extract the memtest86 value
memtest86=$(GetMenuOpt "memtest86" "$memtest86")

 
# Extract the updatedefaultentry option
updatedefaultentry=$(GetMenuOpt "updatedefaultentry" "$updatedefaultentry")

# Extract the savedefault option
savedefault=$(GetMenuOpt "savedefault" "$savedefault")

# Generate the menu options we want to insert
buffer=$(tempfile)
echo $start >> $buffer
echo "## lines between the AUTOMAGIC KERNELS LIST markers will be modified" >> $buffer
echo "## by the debian update-grub script except for the default options below" >> $buffer
echo >> $buffer
echo "## DO NOT UNCOMMENT THEM, Just edit them to your needs" >> $buffer
echo >> $buffer
echo "## ## Start Default Options ##" >> $buffer

echo "## default kernel options" >> $buffer
echo "## default kernel options for automagic boot options" >> $buffer
echo "## If you want special options for specific kernels use kopt_x_y_z" >> $buffer
echo "## where x.y.z is kernel version. Minor versions can be omitted." >> $buffer
echo "## e.g. kopt=root=/dev/hda1 ro" >> $buffer
echo "##      kopt_2_6_8=root=/dev/hdc1 ro" >> $buffer
echo "##      kopt_2_6_8_2_686=root=/dev/hdc2 ro" >> $buffer
echo "# kopt=$kopt" >> $buffer
if [ -n "$CustomKopts" ] ; then
    echo "$CustomKopts" >> $buffer
elif [ -n "$kopt_2_6" ] && [ "$kopt" != "$kopt_2_6" ]; then
    echo "# kopt_2_6=$kopt_2_6" >> $buffer
fi
echo >> $buffer

echo "## default grub root device" >> $buffer
echo "## e.g. groot=(hd0,0)" >> $buffer
echo "# groot=$grub_root_device" >> $buffer
echo >> $buffer

echo "## should update-grub create alternative automagic boot options" >> $buffer
echo "## e.g. alternative=true" >> $buffer
echo "##      alternative=false" >> $buffer
echo "# alternative=$alternative" >> $buffer
echo >> $buffer

echo "## should update-grub lock alternative automagic boot options" >> $buffer
echo "## e.g. lockalternative=true" >> $buffer
echo "##      lockalternative=false" >> $buffer
echo "# lockalternative=$lockalternative" >> $buffer
echo >> $buffer

echo "## additional options to use with the default boot option, but not with the" >> $buffer
echo "## alternatives" >> $buffer
echo "## e.g. defoptions=vga=791 resume=/dev/hda5" >> $buffer
echo "# defoptions=$defoptions" >> $buffer
echo >> $buffer

echo "## should update-grub lock old automagic boot options" >> $buffer
echo "## e.g. lockold=false" >> $buffer
echo "##      lockold=true" >> $buffer
echo "# lockold=$lockold" >> $buffer
echo >> $buffer

echo "## Xen hypervisor options to use with the default Xen boot option" >> $buffer
echo "# xenhopt=$xenhopt" >> $buffer
echo >> $buffer

echo "## Xen Linux kernel options to use with the default Xen boot option" >> $buffer
echo "# xenkopt=$xenkopt" >> $buffer
echo >> $buffer

echo "## altoption boot targets option" >> $buffer
echo "## multiple altoptions lines are allowed" >> $buffer
echo "## e.g. altoptions=(extra menu suffix) extra boot options" >> $buffer
echo "##      altoptions=(single-user) single" >> $buffer

if ! grep -q "^# altoptions" $menu ; then
	echo "# altoptions=$altoptions" >> $buffer
else
	grep "^# altoptions" $menu >> $buffer
fi
echo >> $buffer

echo "## controls how many kernels should be put into the $menu_file_basename" >> $buffer
echo "## only counts the first occurence of a kernel, not the" >> $buffer
echo "## alternative kernel options" >> $buffer
echo "## e.g. howmany=all" >> $buffer
echo "##      howmany=7" >> $buffer
echo "# howmany=$howmany" >> $buffer
echo >> $buffer


echo "## should update-grub create memtest86 boot option" >> $buffer
echo "## e.g. memtest86=true" >> $buffer
echo "##      memtest86=false" >> $buffer
echo "# memtest86=$memtest86" >> $buffer
echo >> $buffer

echo "## should update-grub adjust the value of the default booted system" >> $buffer
echo "## can be true or false" >> $buffer
echo "# updatedefaultentry=$updatedefaultentry" >> $buffer
echo >> $buffer

echo "## should update-grub add savedefault to the default options" >> $buffer
echo "## can be true or false" >> $buffer
echo "# savedefault=$savedefault" >> $buffer
echo >> $buffer

echo "## ## End Default Options ##" >> $buffer
echo >> $buffer

echo -n "Searching for splash image ... " >&2
current_splash=`grep '^splashimage=' ${menu_file} || true`
grub_dir_rel=`make_system_path_relative_to_its_root $grub_dir`
splashimage_path="splashimage=${grub_root_device}/${grub_dir_rel##${kernel_dir}}/splash.xpm.gz"
if [ `sed -e "/^$start/,/^$end/d" $menu_file | grep -c '^splashimage='` != "0" ] ; then
       #checks for splashscreen defined outside the autoupdated part
       splashimage=$(grep '^splashimage=' ${menu_file})
       echo "found: ${splashimage##*=}" >&2
       echo >&2  
elif [ -f "${grub_dir}/splash.xpm.gz" ]  && [ "$current_splash" = "" ]; then
       echo "found: /boot/grub/splash.xpm.gz" >&2
       echo "$splashimage_path" >> $buffer
       echo >> $buffer
elif [ -f "${grub_dir}/splash.xpm.gz" ]  && [ "$current_splash" = "$splashimage_path" ]; then
       echo "found: /boot/grub/splash.xpm.gz" >&2
       echo "$splashimage_path" >> $buffer
       echo >> $buffer
elif [ "$current_splash" != "" ] && [ "$current_splash" != "$splashimage_path" ]; then
       echo "found but preserving previous setting: $(grep '^splashimage=' ${menu_file})" >&2
       echo "$current_splash" >> $buffer
       echo >> $buffer
else
       echo "none found, skipping ..." >&2
fi

xen0Kernels=""
# First kernels with xen0 support.
for ver in `grep -l CONFIG_XEN=y /boot/config* | sed -e s%/boot/config-%%`; do
  if ! grep -q CONFIG_XEN_PRIVILEGED_GUEST=y /boot/config-$ver ; then
      continue
  fi
  # ver is a kernel version
  kern="/boot/vmlinuz-$ver"
  if [ -r $kern ] ; then
       newerKernels=""
       for i in $xen0Kernels ; do
                res=$(CompareVersions "$kern" "$i")
                if [ "$kern" != "" ] && [ "$res" -gt 0 ] ; then
                        newerKernels="$newerKernels $kern $i"
                        kern=""
                else
                        newerKernels="$newerKernels $i"
                fi
        done
        if [ "$kern" != "" ] ; then
                newerKernels="$newerKernels $kern"
        fi
        xen0Kernels="$newerKernels"
    fi
done

sortedKernels=""
for kern in $(/bin/ls -1vr /boot | grep -v "dpkg-*" | grep "^vmlinuz-") ; do
        kern="/boot/$kern"
	newerKernels=""
	for i in $sortedKernels ; do
	    res=$(CompareVersions "$kern" "$i")
	    if [ "$kern" != "" ] && [ "$res" -gt 0 ] ; then
		newerKernels="$newerKernels $kern $i"
	 	kern=""
	    else
		newerKernels="$newerKernels $i"
	    fi
	done
	if [ "$kern" != "" ] ; then
	    newerKernels="$newerKernels $kern"
	fi
	sortedKernels="$newerKernels"
done

if test -f "/boot/vmlinuz.old" ; then
	sortedKernels="/boot/vmlinuz.old $sortedKernels"
fi
if test -f "/boot/vmlinuz" ; then
	sortedKernels="/boot/vmlinuz $sortedKernels"
fi

hypervisors=""
for hyp in /boot/xen-*.gz; do
    if [ ! -h "$hyp" ] && [ -f "$hyp" ]; then
	hypervisors="$hypervisors `basename "$hyp"`"
    fi
done

#Finding the value the default line
use_grub_set_default="false"
if test "$updatedefaultentry" = "true" ; then
	defaultEntryNumber=$(sed -ne 's/^[[:blank:]]*default[[:blank:]]*\(.*\).*/\1/p' $menu)

	if [ "$defaultEntryNumber" = "saved" ] ; then
	    defaultEntryNumber=$(sed 'q' "$grub_dir/default")
	    use_grub_set_default="true"	   
	fi
	
	if test -n "$defaultEntryNumber"; then	
		defaultEntryNumberPlusOne=$(expr $defaultEntryNumber \+ 1);
		defaultEntry=$(grep "^[[:blank:]]*title" $menu | sed -ne "${defaultEntryNumberPlusOne}p" | sed -ne ";s/^[[:blank:]]*title[[:blank:]]*//p")
		defaultEntry=$(echo $defaultEntry | sed -e "s/[[:blank:]]*$//") # don't trust trailing blanks	
	else
		notChangeDefault="yes"
	fi
else
		notChangeDefault="yes"
fi

## heres where we start writing out the kernel entries
counter=0

grub2name="${kernel_dir}/grub/core.img"
if [ "$LET_US_TRY_GRUB_2" = "true" ] \
  && test -f /boot/grub/core.img ; then
	echo "Found GRUB 2: $grub2name" >&2
	cat >> $buffer << EOF
title		Chainload into GRUB 2
root		$grub_root_device
kernel		$grub2name

title		`echo ───────────────────────────────────────────────────────────────────── | iconv -f utf-8 -t cp437`
root
		
title		When you have verified GRUB 2 works, you can use this command to
root

title		complete the upgrade:  upgrade-from-grub-legacy
root

title		`echo ───────────────────────────────────────────────────────────────────── | iconv -f utf-8 -t cp437`
root

EOF
fi
    

# Xen entries first.
for kern in $xen0Kernels ; do
	if test ! x"$howmany" = x"all" ; then
		if [ $counter -gt $howmany ] ; then
			break
		fi
	fi

	kernelName=$(basename $kern)
	kernelVersion=$(echo $kernelName | sed -e 's/vmlinuz//')

	initrdName=$(FindInitrdName "/boot" "$kernelVersion")
	initrd=""

	kernel=$kernel_dir/$kernelName
	if [ -n "$initrdName" ] ; then
		initrd=$kernel_dir/$initrdName
	fi

	kernelVersion=$(echo $kernelVersion | sed -e 's/^-//')
	currentOpt=$(get_kernel_opt $kernelVersion)

	hypervisorVersions=$(FindXenHypervisorVersions "$kernelVersion")

	found=
	for hypervisorVersion in $hypervisorVersions; do
		hypervisor="$kernel_dir/xen-$hypervisorVersion.gz"
		if [ -e "$hypervisor" ]; then
			found=1

			echo "Found Xen hypervisor $hypervisorVersion,  kernel: $kernel" >&2

			write_kernel_entry "$kernelVersion" '' '' "$grub_root_device" \
			  "$kernel" "$currentOpt $xenkopt" '' "$initrd" "$savedefault" '' \
			  Xen "$hypervisor" "$hypervisorVersion" "$xenhopt"
	        counter=$(($counter + 1))
		fi
	done

	if [ -z $found ]; then
		for hypervisor in $hypervisors; do
			hypVersion=`basename "$hypervisor" .gz | sed s%xen-%%`
		
			echo "Found Xen hypervisor $hypVersion,  kernel: $kernel" >&2

			write_kernel_entry "$kernelVersion" '' '' "$grub_root_device" \
			  "$kernel" "$currentOpt $xenkopt" '' "$initrd" "$savedefault" '' \
			  Xen "$kernel_dir/$hypervisor" "$hypVersion" "$xenhopt"
	        counter=$(($counter + 1))
		done
	fi
done

for kern in $sortedKernels ; do
	counter=$(($counter + 1))
	if test ! x"$howmany" = x"all" ; then
		if [ $counter -gt $howmany ] ; then 
			break
		fi
	fi
	kernelName=$(basename $kern)
	kernelVersion=$(echo $kernelName | sed -e 's/vmlinuz//')
	initrdName=$(FindInitrdName "/boot" "$kernelVersion")
	initrd=""

	kernel=$kernel_dir/$kernelName
	if [ -n "$initrdName" ] ; then
		initrd=$kernel_dir/$initrdName
	fi

	echo "Found kernel: $kernel" >&2

	if [ "$kernelName" = "vmlinuz" ]; then
		if [ -L "/boot/$kernelName" ]; then
			kernelVersion=`readlink -f "/boot/$kernelName"`
			kernelVersion=$(echo $kernelVersion | sed -e 's/.*vmlinuz-//')
			kernelVersion="$kernelVersion Default"
		else
			kernelVersion="Default"
		fi
	fi
	if [ "$kernelName" = "vmlinuz.old" ]; then
		if [ -L "/boot/$kernelName" ]; then
			kernelVersion=`readlink -f "/boot/$kernelName"`
			kernelVersion=$(echo $kernelVersion | sed -e 's/.*vmlinuz-//')
			kernelVersion="$kernelVersion Previous"
		else
			kernelVersion="Previous"
		fi
	fi
	kernelVersion=$(echo $kernelVersion | sed -e 's/^-//')
	
	currentOpt=$(get_kernel_opt $kernelVersion)

	do_lockold=$lockold
	# do not lockold for the first entry
	[ $counter -eq 1 ] && do_lockold=false

	write_kernel_entry "$kernelVersion" "" "" "$grub_root_device" "$kernel" \
		"$currentOpt $defoptions" "" "$initrd" "$savedefault" "$do_lockold"

	# insert the alternative boot options
	if test ! x"$alternative" = x"false" ; then
		# for each altoptions line do this stuff
		sed -ne 's/# altoptions=\(.*\)/\1/p' $buffer | while read line; do
			descr=$(echo $line | sed -ne 's/\(([^)]*)\)[[:space:]]\(.*\)/\1/p')
			suffix=$(echo $line | sed -ne 's/\(([^)]*)\)[[:space:]]\(.*\)/\2/p')

			test x"$lockalternative" = x"true" && do_lockold=false
			write_kernel_entry "$kernelVersion" "$descr" "$lockalternative" \
				"$grub_root_device" "$kernel" "$currentOpt" "$suffix" "$initrd" \
				"$savedefault" "$do_lockold"

		done
	fi
done

memtest86names="memtest86 memtest86+"

if test ! x"$memtest86" = x"false" ; then
	for name in $memtest86names ; do
		if test -f "/boot/$name.bin" ; then
			kernelVersion="$name"
			kernel="$kernel_dir/$name.bin"
			currentOpt=
			initrd=

			echo "Found kernel: $kernel" >&2

			write_kernel_entry "$kernelVersion" "" "" "$grub_root_device" \
			"$kernel" "$currentOpt" "" "$initrd" "false" ""
		fi
	done
fi

echo $end >> $buffer

echo -n "Updating $menu ... " >&2
# Insert the new options into the menu
if ! grep -q "^$start" $menu ; then
    cat $buffer >> $menu
    rm -f $buffer
else
    umask 077
    sed -e "/^$start/,/^$end/{
	/^$start/r $buffer
	d
	}
	" $menu > $menu.new
    cat $menu.new > $menu
    rm -f $buffer $menu.new
fi

# Function to update the default value
set_default_value() {
    if [ "$use_grub_set_default" = "true" ] ; then
	if [ -f /usr/lib/grub-legacy/grub-set-default ] ; then
	    /usr/lib/grub-legacy/grub-set-default $1
	else
	    grub-set-default $1
	fi
    else
	value="$1"
	newmenu=$(tempfile)
	sed -e "s/^[[:blank:]]*default[[:blank:]]*[[:digit:]]*\(.*\)/default         ${value}\1/;b" $menu > $newmenu
	cat $newmenu > $menu
	rm -f $newmenu
	unset newmenu
    fi
}

#Updating the default number
if [ "$LET_US_TRY_GRUB_2" = "true" ] && test -f /boot/grub/core.img ; then
	set_default_value "0"
elif test -z "$notChangeDefault"; then
	newDefaultNumberPlusOne=$(grep "^[[:blank:]]*title[[:blank:]]*" $menu | grep -n "${defaultEntry}" | cut -f1 -d ":" | sed -ne "1p")
	if test -z "$newDefaultNumberPlusOne"; then
		echo "Previous default entry removed, resetting to 0">&2
		set_default_value "0"
	elif test -z "$defaultEntry"; then
		echo "Value of default value matches no entry, resetting to 0" >&2
		set_default_value "0"
	else
		if test "$newDefaultNumberPlusOne" = "1"; then
			newDefaultNumber="0"
		else
			newDefaultNumber=$(expr $newDefaultNumberPlusOne - 1)
		fi
		echo "Updating the default booting kernel">&2
		set_default_value "$newDefaultNumber"
	fi
fi

echo "done" >&2
echo >&2
