PC Welt 2006 November (DVD)/PCWELT_11_2006.ISO/casper/filesystem.squashfs/usr/sbin/update-initramfs

Text File | 2006-07-12 | 5.1 KB | 346 lines

#!/bin/sh

STATEDIR=/var/lib/initramfs-tools
BOOTDIR=/boot

set -e

usage()
{
    if [ -n "${1}" ]; then
        printf "${@}\n\n" >&2
    fi
    cat >&2 << EOF
Usage: ${0} [OPTION]...

Options:
 -k [version]    Specify kernel version or all
 -c        Create a new initramfs
 -u        Update an existing initramfs
 -d        Remove an existing initramfs
 -t        Take over a custom initramfs with this one
 -b        Set alternate boot directory
 -v        Be verbose
 -h        This message

EOF
    exit 1
}

mild_panic()
{
    if [ -n "${1}" ]; then
        printf "${@}\n" >&2
    fi
    exit 0
}

panic()
{
    if [ -n "${1}" ]; then
        printf "${@}\n" >&2
    fi
    exit 1
}

verbose()
{
    if [ "${verbose}" = 1 ]; then
        printf "${@}\n"
    fi
}

version_exists()
{
    [ -e "${STATEDIR}/${1}" ]
    return $?
}

set_initramfs()
{
    initramfs="${BOOTDIR}/initrd.img-${version}"
}

generate_initramfs()
{
    echo "update-initramfs: Generating ${initramfs}"
    OPTS="-o"
    if [ "${verbose}" = 1 ]; then
        OPTS="-v $OPTS"
    fi
    if mkinitramfs "${OPTS}" "${initramfs}" "${version}"; then
        set_sha1
    else
        mkinitramfs_return="$?"
        if [ "$mkinitramfs_return" = "2" ]; then
            # minversion wasn't met, exit 0
            exit 0
        fi
        verbose "mkinitramfs failed for ${initramfs}"
        exit $mkinitramfs_return
    fi
}

# only run lilo if no grub is around
run_bootloader()
{
    if [ -x /sbin/grub -o -e /boot/grub/menu.lst ]; then
        if [ -e /etc/lilo.conf ]; then
            echo
            echo "WARNING: grub and lilo installed."
            echo "If you use grub as bootloader everything is fine."
            echo "If you use lilo as bootloader you must run lilo!"
            echo
        fi
        return 0
    fi
    if [ -e /etc/lilo.conf ]; then
        lilo -t > /dev/null
        if [ $? -eq 0 ]; then
            lilo
        fi
    fi
}

compare_sha1()
{
    sha1sum "${initramfs}" | diff "${STATEDIR}/${version}" - >/dev/null 2>&1
    return $?
}

# Note that this must overwrite so that updates work.
set_sha1()
{
    sha1sum "${initramfs}" > "${STATEDIR}/${version}"
}

delete_sha1()
{
    rm -f "${STATEDIR}/${version}"
}

get_sorted_versions()
{
    version_list=""

    for gsv_x in "${STATEDIR}"/*; do
        gsv_x="$(basename "${gsv_x}")"
        if [ "${gsv_x}" = '*' ]; then
            return 0
        fi
        worklist=""
        for gsv_i in $version_list; do
            if dpkg --compare-versions "${gsv_x}" '>' "${gsv_i}"; then
                worklist="${worklist} ${gsv_x} ${gsv_i}"
                gsv_x=""
            else
                worklist="${worklist} ${gsv_i}"
            fi
        done
        if [ "${gsv_x}" != "" ]; then
            worklist="${worklist} ${gsv_x}"
        fi
        version_list="${worklist}"
    done

    verbose "Available versions: ${version_list}"
}

set_current_version()
{
    if [ -f /boot/initrd.img-`uname -r` ]; then
        version=`uname -r`
    fi
}

set_linked_version()
{
    if [ -L /initrd.img ]; then
        linktarget="$(basename "$(readlink /initrd.img)")"
    fi

    if [ -L /boot/initrd.img ]; then
        linktarget="$(basename "$(readlink /boot/initrd.img)")"
    fi

    if [ -z "${linktarget}" ]; then
        return
    fi

    version="${linktarget##initrd.img-}"
}

set_highest_version()
{
    get_sorted_versions
    set - ${version_list}
    version=${1}
}

create()
{
    if [ -z "${version}" ]; then
        usage "Create mode requires a version argument"
    fi

    set_initramfs

    if [ "${takeover}" = 0 ]; then
        if version_exists "${version}"; then
            panic "Cannot create version ${version}: already exists"
        fi

        if [ -e "${initramfs}" ]; then
            panic "${initramfs} already exists, cannot create."
        fi
    fi

    generate_initramfs
}

update()
{
    if [ -z "${version}" ]; then
        set_linked_version
    fi

    if [ -z "${version}" ]; then
        set_highest_version
    fi

    if [ -z "${version}" ]; then
        set_current_version
    fi

    if [ -z "${version}" ]; then
        verbose "Nothing to do, exiting."
        exit 0
    fi

    if [ "${version}" = "all" ]; then
        : FIXME check for --yes, and if not ask are you sure
        get_sorted_versions
        if [ -z "${version_list}" ]; then
            verbose "Nothing to do, exiting."
            exit 0
        fi
        for u_version in ${version_list}; do
            if [ "${verbose}" = "1" ]; then
                vflag="-v"
            fi
            # Don't stop if one version doesn't work.
            set +e
            "${0}" -u -k "${u_version}" ${vflag}
            set -e
        done
        exit 0
    fi

    set_initramfs

    altered_check

    generate_initramfs

    run_bootloader

}

delete()
{
    if [ -z "${version}" ]; then
        usage "Delete mode requires a version argument"
    fi

    set_initramfs

    if [ ! -e "${initramfs}" ]; then
        panic "Cannot delete ${initramfs}, doesn't exist."
    fi

    if ! version_exists "${version}"; then
        panic "Cannot delete version ${version}: Not created by this utility."
    fi

    altered_check

    delete_sha1

    rm -f "${initramfs}"
}


altered_check()
{
    if [ "${takeover}" = 0 ]; then
        if ! compare_sha1; then
            delete_sha1
            mild_panic "${initramfs} has been altered.  Cannot update."
        fi
    fi
}

# Defaults
verbose=0
yes=0
# We default to takeover=1 in Ubuntu, but not Debian
takeover=1

##

while getopts "k:cudyvtb:h?" flag; do
    case "${flag}" in
    k)
        version="${OPTARG}"
        ;;
    c)
        mode="c"
        ;;
    d)
        mode="d"
        ;;
    u)
        mode="u"
        ;;
    v)
        verbose="1"
        ;;
    y)
        yes="1"
        ;;
    t)
        takeover="1"
        ;;
    b)
        BOOTDIR="${OPTARG}"
        if [ ! -d "${BOOTDIR}" ]; then
            echo "Error: ${BOOTDIR} is not a directory."
            exit 1
        fi
        ;;
    h|?)
        usage
        ;;
    esac
done

# Validate arguments

if [ -z "${mode}" ]; then
    usage "You must specify at least one of -c, -u, or -d."
fi

case "${mode}" in
    c)
        create
        ;;
    d)
        delete
        ;;
    u)
        update
        ;;
esac