51-dracut-rescue.install

#!/usr/bin/bash

export LANG=C

COMMAND="$1"
KERNEL_VERSION="$2"
ENTRY_DIR_ABS="$3"
KERNEL_IMAGE="$4"


dropindirs_sort()
{
    suffix=$1; shift
    args=("$@")
    files=$(
        while (( $# > 0 )); do
            for i in "${1}"/*"${suffix}"; do
                [[ -f $i ]] && echo "${i##*/}"
            done
            shift
        done | sort -Vu
    )

    for f in $files; do
        for d in "${args[@]}"; do
            if [[ -f "$d/$f" ]]; then
                echo "$d/$f"
                continue 2
            fi
        done
    done
}

[[ -f /etc/os-release ]] && . /etc/os-release

if [[ ${KERNEL_INSTALL_MACHINE_ID+x} ]]; then
    MACHINE_ID=$KERNEL_INSTALL_MACHINE_ID
elif [[ -f /etc/machine-id ]] ; then
    read -r MACHINE_ID < /etc/machine-id
fi

if ! [[ $MACHINE_ID ]]; then
    exit 0
fi

if [[ -f /etc/kernel/cmdline ]]; then
    read -r -d '' -a BOOT_OPTIONS < /etc/kernel/cmdline
elif [[ -f /usr/lib/kernel/cmdline ]]; then
    read -r -d '' -a BOOT_OPTIONS < /usr/lib/kernel/cmdline
else
    declare -a BOOT_OPTIONS

    read -r -d '' -a line < /proc/cmdline
    for i in "${line[@]}"; do
        [[ "${i#initrd=*}" != "$i" ]] && continue
        BOOT_OPTIONS+=("$i")
    done
fi
BOOT_ROOT=${ENTRY_DIR_ABS%/$MACHINE_ID/$KERNEL_VERSION}
LOADER_ENTRY="$BOOT_ROOT/EFI/Linux/0-rescue-$MACHINE_ID.efi"
BOOT_DIR_ABS="$BOOT_ROOT/EFI/Linux"
ret=0

case "$COMMAND" in
    add)
        [[ -f "$LOADER_ENTRY" ]] && exit 0

        # source our config dir
        for f in $(dropindirs_sort ".conf" "/etc/dracut.conf.d" "/usr/lib/dracut/dracut.conf.d"); do
            if [[ -e $f ]]; then
                # shellcheck disable=SC1090
                . "$f"
            fi
        done

        # shellcheck disable=SC2154
        [[ $dracut_rescue_image != "yes" ]] && exit 0

        [[ -d "$BOOT_DIR_ABS" ]] || mkdir -p "$BOOT_DIR_ABS"

        dracut --kernel-cmdline "${BOOT_OPTIONS[*]}" -f --no-hostonly -a "rescue" --uefi "$LOADER_ENTRY" "$KERNEL_VERSION"

        ((ret+=$?))
        ;;

    remove)
        exit 0
        ;;

    *)
        usage
        ret=1;;
esac

exit $ret