diff options
Diffstat (limited to 'update-initramfs')
| -rw-r--r-- | update-initramfs | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/update-initramfs b/update-initramfs new file mode 100644 index 0000000..9d7d1bc --- /dev/null +++ b/update-initramfs @@ -0,0 +1,281 @@ +#!/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: ${0} [OPTION]... + +Options: + -k [version] Specify kernel version or ALL + -c Create a new initramfs + -u Update an existing initramfs + -d Remove an existing initramfs + -t Take over a custom initramfs with this one + -v Be verbose + -h This message + +EOF + exit 1 +} + +mild_panic() +{ + if [ -n "${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() +{ + verbose "Generating ${initramfs}" + mkinitramfs -o ${initramfs} ${version} + set_sha1 +} + +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 + verbose "Nothing to do, exiting." + exit 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: ${version_list}" +} + +set_linked_version() +{ + if [ -L /initrd.img ]; then + linktarget=$(readlink /initrd.img) + fi + + if [ -L /boot/initrd.img ]; then + linktarget=$(readlink /boot/initrd.img) + fi + + if [ -z "${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 [ "${version}" = "all" ]; then + : FIXME check for --yes, and if not ask are you sure + get_sorted_versions + 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} ${vflag} -u -k ${u_version} + set -e + done + exit 0 + fi + + set_initramfs + + altered_check + + generate_initramfs + +} + +delete() +{ + if [ -z "${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} was been altered. Cannot update." + fi + fi +} + +# Defaults +verbose=0 +yes=0 +takeover=0 + +## + +while getopts "k:cudyvht" 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" + ;; + 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 + + |