#!/bin/bash

# vim:expandtab:shiftwidth=4:softtabstop=4:tabstop=4:

# this is an alternative FD for stdout, to be used especially when we are
# taking stdout from a function as it's return value.  i.e. foo=$(bar)
# this is a workaround until a version of bash where we can put xtrace
# on a specific FD
exec 3>&1; STDOUT=3

#set -x
xtrace="+x"
if [[ $SHELLOPTS = *xtrace* ]]; then
    xtrace="-x"
fi
shopt -s extdebug

# Assume that lbuild's support files can be found in the same
# canonicalized path as this very script.
LBUILD_SCRIPT=$(readlink -f ${0})
LBUILD_DIR=${LBUILD_DIR:-$(dirname ${LBUILD_SCRIPT})}

# include the exit_traps library
. ${LBUILD_DIR}/exit_traps.sh
. ${LBUILD_DIR}/funcs.sh

# our children should die when we do
push_exit_trap "kill -INT -$$ || true" kill_children

# increment this if you have made a change that should force a new kernel
# to build built
#BUILD_GEN=1
#BUILD_GEN=2	# bz19952: remove -lustre tag from kernel RPM names
#BUILD_GEN=3	# bz19975: enable the building of src.rpms by default
#BUILD_GEN=4	# bz22281: use the git hash in the kernel extra version
#BUILD_GEN=5	# TT-107: don't cache the BUILD dir
BUILD_GEN=6	# TT-1092: don't cache the BUILD dir, to rebuild external OFED

TOPDIR=$PWD

KERNELDIR=
LINUX=
LUSTRE=
RELEASE=false
# XXX - some recent hacking has pretty much neutered this option.
#       search through this file for "-bb" and see how many places
#       simply don't account for this option
DO_SRC=true
DOWNLOAD=true
CANONICAL_TARGET=
TARGET=
TARGET_ARCH="$(uname -m)"
# change default behavior to only build for the current arch
TARGET_ARCHS="$TARGET_ARCH"
TARGET_ARCHS_ALL="$TARGET_ARCH"
[ "$TARGET_ARCH" = "i686" ] && TARGET_ARCHS_ALL="i686 i586 i386"
CONFIGURE_FLAGS=
EXTERNAL_PATCHES=
EXTRA_VERSION=
STAGEDIR=
TMPDIR=${TMPDIR:-"/var/tmp"}
TIMESTAMP=
# this is a dir to try reuse old kernel RPMs in (although, it seems to be
# unused in any real manner
REUSERPM=
# this is the dir that should be used to store reuse products
REUSEBUILD=
# should cached products be used or force rebuilding?
USE_BUILD_CACHE=true
# what does this do exactly?  does it imply no kernel build?
NORPM=false
IOKITRPM=true
OSDLDISKFSRPM=true
OSDZFSRPM=false
SMPTYPES="smp bigsmp default ''"
PATCHLESS=false
XEN=false
LINUXOBJ=
DISTRO=
KERNELTREE=
# default to not adding -lustre- into the kernel RPM package names
KERNEL_LUSTRE_NAMING=false
# default not use kabi check.
USE_KABI=false

# patchless build
KERNELRPMSBASE=
RPMSMPTYPE=

# from target file
SERIES=
BASE_ARCHS=
BIGMEM_ARCHS=
BOOT_ARCHS=
JENSEN_ARCHS=
SMP_ARCHS=
BIGSMP_ARCHS=
PSERIES64_ARCHS=
UP_ARCHS=

# not in the target file any more
CONFIG=

# build the lustre-tests rpm?
LUSTRE_TESTS=true

DATE=$(date)

RPMBUILD=

export CC=${CC:-gcc}

# Readlink is not present on some older distributions: emulate it.
readlink() {
    local path=$1 ll

    if [ -L "$path" ]; then
        ll="$(LC_ALL=C ls -l "$path" 2> /dev/null)" &&
        echo "${ll/* -> }"
    else
        return 1
    fi
}

usage() {
    cat <<EOF
Usage: ${0##*/} [OPTION]... [-- <lustre configure options>]

  --external-patches=EXTERNAL_PATCHES
    Directory similar to lustre/lustre/kernel_patches/ that lbuild should
    look for seres and config files in before looking in the lustre
    tree.

  --extraversion=EXTRAVERSION
    Text to use for the rpm release and kernel extraversion.

  --timestamp=TIMESTAMP
    Date of building lustre in format YYYYMMDDhhmmss

  --reuserpm=DIR
    Try to reuse old kernel RPMs from DIR

  --reusebuild=DIR
    Try to reuse old kernel builds from DIR

  --kernelrpm=DIR
    Path to distro kernel RPM collection

  --ccache
    Use ccache

  --norpm
    Do not build RPMs (compile only mode)

  --patchless
    Build lustre client only

  --distro=DISTRO
    Which distro using. Autodetect by default

  --kerneldir=KERNELDIR
    Directory containing Linux source tarballs referenced by target
    files.

  --kerneltree=KERNELTREE
    Directory containing dirs with Linux source tarballs referenced by target
    files. Dir names in format kernel version ('2.6.9', etc.)

  --linux=LINUX --with-linux=LINUX
    Directory of Linux kernel sources.  When this option is used, only
    Lustre modules and userspace are built.

  --lustre=LUSTRE
    Path to an existing lustre source tarball to use.

  --nodownload
    Do not try to download a kernel from downloads.lustre.org

  --nosrc
    Do not build a .src.rpm, a full kernel patch, or a patched kernel
    tarball.

  --ldiskfs
    Build with ldiskfs support. (Deprecated, always true)

  --noiokit
    Do not build lustre-iokit RPM. Now true by default

  --publish
    Unused.

  --release
    Specifies that the files generated do not include timestamps, and
    that this is an official release.

  --src
    Build a .src.rpm, a full kernel patch, and a patched kernel tarball.

  --stage=DIR
    Directory used to stage packages for release.  RPMs will be placed
    more or less in DIR/<target>-<arch>, and the tarball will be
    placed in DIR.

  --target=TARGET
    The name of the target to build.  The available targets are listed
    below.

  --target-archs=TARGET_ARCHS
    A (space delimited) list of architectures to build.  By default,
    all of the archs supported by the TARGET will be built, in
    addition to a .src.rpm.  This option can limit those, for machines
    that can only build certain archs or if you only want a certain
    arch built (for testing, or a one-off kernel).

    Also note that by using a non-"base" arch (eg, i386) only kernels
    will be built - there will be no lustre-lite-utils package.

  --xen
    Builds a Xen domX kernel.

  --set-value
    Sets a variable to a given value.

EOF

#   list_targets

    fatal "$1" "$2"
}

# canonicalize a relative path to a file
canon_filepath() {
    local PATH="$1"

    if [ ! -f "$PATH" ]; then
        return 1
    fi

    local FILE=${PATH##*/}
    local DIR=${PATH%/*}

    echo $(canon_path "$DIR")/$FILE
    return 0
}

# canonicalize a relative path to a dir
canon_path() {
    local PATH="$1"

    if [ ! -d "$PATH" ]; then
        return 1
    fi

    pushd "$PATH" >/dev/null || return 1
    local CANONPATH=$PWD
    popd >/dev/null

    echo "$CANONPATH"
    return 0
}

check_options() {

    if [ -z "$LUSTRE" -o ! -r "$LUSTRE" ]; then
        usage 1 "Could not find Lustre source tarball '$LUSTRE'."
    fi

    if [ -z "$DISTRO" ] ; then
        DISTRO=$(autodetect_distro)
        # remove minor version only for rhel and oel
        [[ $DISTRO =~ "el-" ]] && DISTRO=${DISTRO%%.*}
        # remove separator
        DISTRO=${DISTRO/-/}
    fi

    [ -z "$TARGET" ] && TARGET=$(autodetect_target "$DISTRO")

    if [ -z "$LINUX" ]; then
        [ "$KERNELDIR" -o "$KERNELTREE" ] || \
            usage 1 "A kernel directory must be specified with --kerneldir or --kerneltree."

        [ -d "$KERNELDIR" -o -d "$KERNELTREE" ] || \
            usage 1 "$KERNELDIR and $KERNELTREE are not a directory."

#       TARGET_FILE="$TOPDIR/lustre/kernel_patches/targets/$TARGET.target"
#       [ -r "$TARGET_FILE" ] || \
#               usage 1 "Target '$TARGET' was not found."
    fi

    case $TARGET in
        2.6-rhel6)
            CANONICAL_TARGET="rhel6"
            ;;
        2.6-rhel5)
            CANONICAL_TARGET="rhel5"
            ;;
        2.6-rhel4)
            CANONICAL_TARGET="rhel-2.6"
            ;;
        2.6-suse)
            CANONICAL_TARGET="sles-2.6"
            ;;
        2.6-sles10)
            CANONICAL_TARGET="sles10-2.6"
            ;;
        2.6-sles11 | 3.0-sles11)
            CANONICAL_TARGET="sles11"
            ;;
        2.6-oel5)
            CANONICAL_TARGET="oel5"
            ;;
        hp_pnnl-2.4)
            CANONICAL_TARGET="hp-pnnl-2.4"
            ;;
        2.6-vanilla \
            | suse-2.4.21-2 \
            | rh-2.4 \
            | rhel-2.4 \
            | sles-2.4 \
            | 2.6-patchless)
                CANONICAL_TARGET="$TARGET"
                ;;
    esac

    local timestampnodig=$(echo $TIMESTAMP | sed -e s/[0-9]*//g)
    [ "$timestampnodig" = "" ] || TIMESTAMP=$(date -d "$DATE" "+%Y%m%d%H%M%S")
    local timestamplength="${#TIMESTAMP}"
    if [ $timestamplength -eq 12 ]; then
        TIMESTAMP="${TIMESTAMP}00"
    elif [ $timestamplength -ne 14 ]; then
        TIMESTAMP=$(date -d "$DATE" "+%Y%m%d%H%M%S")
    fi

    RPMBUILD=$(which rpmbuild 2>/dev/null | head -1)
    if [ ! "$RPMBUILD" -o "$RPMBUILD" == "" ]; then
        RPMBUILD=$(which rpm 2>/dev/null | head -1)
        if [ ! "$RPMBUILD" -o "$RPMBUILD" == "" ]; then
            usage 1 "Could not find binary for making rpms (tried rpmbuild and rpm)."
        fi
    fi

    if [ -n "$CCACHE" ]; then
        which "$DISTCC" &>/dev/null && export DISTCC RPM_BUILD_NCPUS

        if which "$CCACHE" &>/dev/null; then
            local ccache=$(which "$CCACHE")
            local bindir="$TOPDIR/bin"

            if [ ! -d $bindir ]; then
                mkdir -p $bindir || fatal 1 "error trying to create $bindir"
            else
                rm ${bindir}/* > /dev/null 2>&1 || true
            fi
            ln -s "$ccache" ${bindir}/ccache
            ln -s "$ccache" ${bindir}/cc
            ln -s "$ccache" ${bindir}/$CC
            export PATH=$bindir:$PATH
            export CCACHE && export CC="ccache $CC"
            # zero the cache so we can see how effective we are being with it
            echo -n "ccache "
            ccache -z

            # get some ccache stats when we are done
            push_exit_trap '[ -n "$CCACHE" ] && ccache -s' "ccache_summary"
            # should remove the ccache trap if lbuild is interrupted
            trap 'echo "Received an INT TERM or HUP signal, terminating."; delete_exit_trap "ccache_summary"; exit 1' INT TERM HUP
        fi
    fi

    return 0

}

# compare two versions $1 and $2. if $1 < $2, return 0 otherwise return 1.
compare_version () {
    [[ $1 == $2 ]] && return 1
    local IFS=.
    local i val1=($1) val2=($2)

    # padding zero to val1 if it needs
    for ((i=${#val1[@]}; i<${#val2[@]}; i++)); do
        val1[i]=0
    done
    for ((i=0; i<${#val1[@]}; i++)); do
        [[ -z ${val2[i]} ]] && return 1

        if [[ ${val1[i]} < ${val2[i]} ]]; then
            return 0
        elif [[ ${val1[i]} > ${val2[i]} ]]; then
            return 1
        fi
    done
}

uniqify() {

    echo $(echo "$*" | xargs -n 1 | sort -u)

}

fetch_url() {
    local url="$1"
    local target="$2"

    if [ -z "$target" ]; then
        fatal 1 "fetch_url() called without a target to fetch to"
    fi

    if [ -d $target ]; then
        target+="/${url##*/}"
    fi

    local rc=0
    if which wget >/dev/null 2>&1; then
        if ! wget -nv "$url" -O "$target"; then
            rc=${PIPESTATUS[0]}
        fi
    elif which curl >/dev/null 2>&1; then
        if ! curl -n -L -s -o "$target" "$url"; then
            rc=${PIPESTATUS[0]}
        fi
    else
        fatal 1 "Could not find either wget or curl to fetch URLs."
    fi

    return $rc

}

download_srpm() {
    local target=$1
    local srpm=$2
    local force="${3:-false}"

    if $force || [ ! -r "$KERNELDIR/$srpm" ] ||
       [ ! -s "$KERNELDIR/$srpm" ]; then
        if $DOWNLOAD; then
            local location="http://downloads.lustre.org/public/kernels/$target/old"
            # get the location from a distro specific method if it exists
            if type -p kernel_srpm_location; then
                location=$(kernel_srpm_location)
            fi
            echo "Downloading $location/$srpm..."
            if ! fetch_url "$location/$srpm" "$KERNELDIR/$srpm" 2>&1 ||
               [ ! -s "$KERNELDIR/$srpm" ]; then
                rm -f $KERNELDIR/$srpm
                # punt to a distro specific method if it exists
                if ! type -p download_srpm-$DISTRO; then
                    fatal 1 "Could not download target $target's kernel SRPM $srpm from $location."
                else
                    if ! download_srpm-$DISTRO "$target" "$srpm" "$force"; then
                        fatal 1 "Could not download target $target's kernel SRPM $srpm using download_srpm-$DISTRO."
                    fi
                fi
            fi
        else
            fatal 1 "$srpm not found in directory $KERNELDIR."
        fi
    fi

}

download_file() {
    local from="$1"
    local to="$2"
    local force="$3"

    local file=${from##*/}

    if [ -d $to ]; then
        to="$to/$file"
    fi

    local semaphore="$to-downloading"

    is_downloading() {
        if [ ! -f $semaphore ]; then
            return 1
        fi

        # make sure the download has not been aborted
        local now=$(date +%s)
        local file_mtime=$(stat -c %Y "$to")
        local staleness=$((now - file_mtime))
        # let's assume an active download will write at least once a minute
        if [ $staleness -gt 60 ]; then
            return 1
        fi

        return 0
    }

    is_downloaded() {
        # if the semaphore file exists, the file is either still downloading
        # or a download was aborted and we cannot trust the target file
        if [ -f $semaphore ]; then
            return 1
        fi

        if ! is_downloading && [ -r "$to" ] && [ -s "$to" ]; then
            return 0
        fi

        return 1
    }

    if $force || ! is_downloaded; then
        if is_downloading; then
            echo "Somebody else is downloading $from..."
            while is_downloading; do
                echo "Waiting for $to to finish downloading"
                sleep 60
            done
            if is_downloaded; then
                return 0
            else
                echo "The download we were waiting for seems to have been aborted"
            fi

        fi

        if $DOWNLOAD; then
            echo "Downloading $from..."
            # flag others so they don't try to download also
            push_exit_trap "rm -f $to $semaphore" "download"
            touch $semaphore
            if ! fetch_url "$from" "$to" || [ ! -s "$to" ]; then
                # the trap will remove the files via the fatal below
                fatal 1 "Could not download ${to##*/} from ${from%/*}/."
            fi
            rm -f $semaphore
            delete_exit_trap "download"
        else
            fatal 1 "${to##*/} not found in directory ${to%/*}."
        fi
    fi

    return 0

}

download_ofed() {
    local force="${1:-false}"

    if [ -z "$OFED_VERSION" -o "$OFED_VERSION" = "inkernel" ]; then
        return 0
    fi

    local OFED_BASE_VERSION=$OFED_VERSION
    if [[ $OFED_VERSION = *.*.*.* ]]; then
        OFED_BASE_VERSION=${OFED_VERSION%.*}
    fi

    local location="http://www.openfabrics.org/downloads/OFED/ofed-${OFED_BASE_VERSION}/"

    if [[ $OFED_VERSION = *-[rR][cC][0-9] ]]; then
        local Mmv
        Mmv=${OFED_VERSION%%-[rR][cC][0-9]}
        location="http://www.openfabrics.org/downloads/OFED/ofed-${Mmv}/"
    fi

    if [[ $OFED_VERSION = daily-* ]]; then
        local Mmv daily
        OFED_VERSION=${OFED_VERSION/daily-/}
        Mmv=${OFED_VERSION%%-*}
        daily=${OFED_VERSION##$Mmv-}
        location="http://www.openfabrics.org/downloads/OFED/ofed-${Mmv}-daily/"
        # find the filename for the version for the date specified
        OFED_VERSION=$(curl -s "$location" | sed -nre "/${daily}-/s/.*href=\"OFED-(${Mmv//./\\.}-${daily}-[0-9]{4,4}).tgz.*$/\1/p" | tail -1)
        if [ -z "$OFED_VERSION" ]; then
            fatal 1 "Could not determine the filename of the OFED snapshot for ${daily}"
        fi
    fi

    local file="OFED-${OFED_VERSION}.tgz"
    download_file "$location/$file" "$KERNELTREE" "$force"

}

parse_mpss_info() {
    local file="$1"
    local build="$2"
    local distro="$3"

    [ -r "$file" ] || fatal 1 "Could not find MPSS info file"

    # convert to MPSS distro naming
    distro=${distro/sles/suse}
    distro_name=${distro%%-*}

    # extract links from MPSS info file
    local urls=$(cat "$file" | \
        tr -d '\t\r\n' | sed -e 's?\(</[a-zA-Z]*>\)?\1\n?g' | \
        grep '.intel.com/' | \
        sed -e 's/^.*[hH][rR][eE][fF]="\([^>"]\+\)".*$/\1/g' | \
        grep '.tar')
    local res2=""
    local res3=""
    for url in $urls; do
        local ver2=""
        local ver3=""
        # Try to match with MPSS 3.x or 3.x.x distro package
        if [[ $url =~ mpss-[0-9].[0-9](.[0-9]*)?-$distro.tar ]]; then
            ver3=${url##*mpss-}
            ver3=${ver3%%-$distro.tar}
        # Try to match with MPSS 3.x or 3.x.x source package
        elif [[ $url =~ mpss-src-[0-9].[0-9](.[0-9]*)?.tar ]]; then
            ver3=${url##*mpss-src-}
            ver3=${ver3%%.tar}
        # Try to match with MPSS 3.x or 3.x.x cross compiler package
        elif [[ $url =~ mpss-[0-9].[0-9](.[0-9]*)?-k1om.tar ]]; then
            ver3=${url##*mpss-}
            ver3=${ver3%%-k1om.tar}
        # Try to match with MPSS 2.1.x source package
        elif [[ $url =~ _src-[0-9].[0-9].[0-9]*-[0-9]*_$distro_name.tar ]]; then
            ver2=${url##*_src-}
            ver2=${ver2%%_$distro_name.tar}
        fi

        if [ -n "$ver3" ]; then
            # Check for MPSS 3.x or MPSS 3.x.x
            if [[ $ver3 =~ [0-9].[0-9].[0-9]* ]]; then
                ver3="${ver3}-0"
            else
                ver3="${ver3}.0-0"
            fi
            if [ -z "$build" ]; then
                res3="$ver3"
            elif [ "$build" = "$ver3" ]; then
                res3="$res3 $url"
            fi
        elif [ -n "$ver2" ]; then
            if [ -z "$build" ]; then
                res2="$ver2"
            elif [ "$build" = "$ver2" ]; then
                res2="$res2 $url"
            fi
        fi

    done

    if [ -z "$build" ]; then
        # return a last version of MPSS
        if [ -n "$res3" ]; then
            echo "$res3"
        else
            echo "$res2"
        fi
    elif [ "${build%%.*}" = "3" ]; then
        local ver=${build%%-*}
        local bid=${build##*-}
        if [ $bid -eq 0 ]; then
            # return URLs from MPSS info file
            echo "$res3"
        else
            # Check for MPSS 3.x or MPSS 3.x.x
            if [ ${ver##*.} -eq 0 ]; then
                ver=${ver%.*}
            fi
            # return URLs from internal site with MPSS builds
            # kernel sources:
            echo "${MPSS_BUILDS:-"http://mic-bld.pdx.intel.com/release"}/$ver/$bid/release/knightscorner/package/mpss-src-$ver.tar"
            # kernel configs:
            echo "${MPSS_BUILDS:-"http://mic-bld.pdx.intel.com/release"}/$ver/$bid/release/knightscorner/package/mpss-$ver-k1om.tar"
            # OFED headers:
            echo "${MPSS_BUILDS:-"http://mic-bld.pdx.intel.com/release"}/$ver/$bid/release/knightscorner/package/mpss-$ver-$distro.tar"
        fi
    else
        # return URLs from MPSS info file
        echo "$res2"
    fi
}

# Get public information about last releases of
# Intel Manycore Platform Software Stack (MPSS)
download_mpss_info() {
    local file="$1"
    local force="${2:-true}"
    local url=${MPSS_URL:-"http://software.intel.com/en-us/articles/intel-manycore-platform-software-stack-mpss"}

    download_file "$url" "$file" "$force"
}

download_mpss() {
    local file="$1"
    local force="${2:-false}"
    local urls=$(parse_mpss_info "$file" ${MPSS_VERSION} ${MPSS_DISTRO})

    [ -z "$urls" ] && fatal 1 "Could not determine the URLs of MPSS $MPSS_VERSION"

    # force re-download if build number is zero
    [[ $MPSS_VERSION = [0-9].[0-9].[0-9]*-0 ]] && force=true

    local url
    local i=0
    for url in $urls; do
        file="$KERNELTREE/mpss_src-${MPSS_VERSION}-${MPSS_DISTRO}-part$i.tar"
        download_file "$url" "$file" "$force"
        i=$((i+1))
    done
}

load_target() {

    EXTRA_VERSION_save="$EXTRA_VERSION"
    for patchesdir in "$EXTERNAL_PATCHES" \
                      "$TOPDIR/lustre/lustre/kernel_patches"; do
        TARGET_FILE="$patchesdir/targets/$TARGET.target"
        [ -r "$TARGET_FILE" ] && break
    done
    [ -r "$TARGET_FILE" ] || fatal 1 "Target $TARGET was not found."

    echo "Loading target config file $TARGET.target..."

    # if the caller specified an OFED_VERSION it should override whatever
    # the target file specifies
    local env_OFED_VERSION="$OFED_VERSION"

    . "$TARGET_FILE"

    if [ -n "$env_OFED_VERSION" ]; then
        OFED_VERSION="$env_OFED_VERSION"
    fi

    # doesn't make any sense to build OFED for xen domX's
    if $XEN; then
        OFED_VERSION=""
    fi

    # XXX - set_rpm_smp_type is an ugly undeterministic hack.  it needs to
    #       go away and the target just specify the $RPMSMPTYPE
    [ -z "$RPMSMPTYPE" ] && set_rpm_smp_type

    # CC might have been overwriten in TARGET_FILE
    if [[ $CC != ccache\ * ]] && which "$CCACHE" &>/dev/null; then
        export CCACHE && export CC="ccache $CC"
    fi

    if [ ! "$KERNELTREE" = "" ] && [ -d "$KERNELTREE" ]; then
        KERNELDIR="$KERNELTREE/${lnxmaj}"
        [ -d "$KERNELDIR" ] || mkdir "$KERNELDIR"
    fi

    # verify the series is available
    if [ "$SERIES" ]; then
        for series in $SERIES; do
            for patchesdir in "$EXTERNAL_PATCHES" "$TOPDIR/lustre/lustre/kernel_patches"; do
                [ -r "$patchesdir/series/$series" ] && continue 2
            done
            fatal 1 "Target $TARGET's series $SERIES could not be found.\nSearched:\n\t$EXTERNAL_PATCHES/series\n\t$TOPDIR/lustre/lustre/kernel_patches/series."
        done
    fi

    # set the location of the .config file
    local XENPOSTFIX=""
    if $XEN; then
        XENPOSTFIX="-xen"
    fi

    if [ -f $TOPDIR/lustre/lustre/kernel_patches/kernel_configs/kernel-$lnxmaj-$TARGET-$TARGET_ARCH.config ]; then
        CONFIG_FILE="$TOPDIR/lustre/lustre/kernel_patches/kernel_configs/kernel-$lnxmaj-$TARGET$XENPOSTFIX-$TARGET_ARCH.config"
    fi

    local lnxrelnew=${lnxrel//-/_}

    # remember the EXTRA_VERSION before we diddle it here
    # XXX - we really should not diddle with any values read in from the
    #       target file.  if we want to modify a value, we should create
    #       a new variable.
    PRISTINE_EXTRA_VERSION=$EXTRA_VERSION

    if ! $PATCHLESS && [ ! -f "$CONFIG_FILE" ]; then
        fatal 1 "Config file for target $TARGET missing from $TOPDIR/lustre/lustre/kernel_patches/kernel_configs/."
    fi

    if [ "$EXTRA_VERSION_save" ]; then
        EXTRA_VERSION="$EXTRA_VERSION_save"
    elif ! $RELEASE; then
        # if there is no patch series, then this is not a lustre specific
        # kernel.  don't make it look like one
        if $PATCHLESS || [ -n "$SERIES" ]; then
            EXTRA_VERSION=$(echo $EXTRA_VERSION | sed -e "s/\(.*_lustre\)\..*/\1/")
            if ! $PATCHLESS && [ -n "$BUILDID" ]; then
                EXTRA_VERSION="${EXTRA_VERSION}.${BUILDID}"
            fi
        fi
    fi
    # EXTRA_VERSION=${EXTRA_VERSION//-/_}

    ALL_ARCHS="$BASE_ARCHS $BIGMEM_ARCHS $BOOT_ARCHS $JENSEN_ARCHS $SMP_ARCHS $BIGSMP_ARCHS $PSERIES64_ARCHS $UP_ARCHS"

    BUILD_ARCHS=
    for arch in $(uniqify "$ALL_ARCHS"); do
        if [ -z "$TARGET_ARCHS" ] ||
           [[ \ $TARGET_ARCHS\  = *\ $arch\ * ]]; then
            BUILD_ARCHS="$BUILD_ARCHS $arch"
        fi
    done
    [ "$BUILD_ARCHS" ] || usage 1 "No available target archs to build."
    echo "Building for: $BUILD_ARCHS"
}

tarflags() {
    local file="$1"

    case "$file" in
        '')
            fatal 1 "tarflags(): File name argument missing."
            ;;
        *.tar.gz | *.tgz)
            echo 'zxf'
            ;;
        *.tar.bz2)
            echo 'jxf'
            ;;
        *.tar)
            echo 'xf'
            ;;
        *)
            fatal 1 "tarflags(): Unrecognized tar extension in file: $1"
            ;;
    esac

}

untar() {
    local tarfile="$1"
    shift
    local extractfile="$@"

    echo "Untarring ${tarfile##*/}..."
    tar $(tarflags "$tarfile") "$tarfile" $extractfile

}

unpack_ofed() {

    if ! untar "$KERNELTREE/OFED-${OFED_VERSION}.tgz"; then
        return 1
    fi
    [ -d OFED ] || ln -sf OFED-[0-9].[0-9]* OFED

}

unpack_lustre() {

    untar "$LUSTRE" || fatal 1 "Error unpacking Lustre tarball"
    [ -d lustre ] || ln -sf lustre-[0-9].[0-9]* lustre

}

unpack_mpss() {

    [ -d mpss ] && return 0

    if [ "${MPSS_VERSION%%.*}" = "3" ]; then
        local ver=${MPSS_VERSION%%-*}
        local file
        local i
        # Check for MPSS 3.x or MPSS 3.x.x
        if [ ${ver##*.} -eq 0 ]; then
            ver=${ver%.*}
        fi
        for i in $(seq 0 9); do
            file="$KERNELTREE/mpss_src-${MPSS_VERSION}-${MPSS_DISTRO}-part$i.tar"
            if [ -r "$file" ]; then
                untar "$file" \
                    "mpss-$ver/*/linux-*.tar.bz2" \
                    "mpss-$ver/*/kernel-dev-*.rpm" \
                    "mpss-$ver/*/ofed-driver-*-devel-*.rpm"
            fi
        done
        # Extract kernel configs
        file=$(find mpss-$ver -type f -path "*/kernel-dev-*.rpm")
        if ! rpm2cpio "$file" | cpio -idm; then
            echo "Error extracting MPSS kernel configs"
            return 1
        fi
        # Unpack kernel sources
        file=$(find mpss-$ver -type f -path "*/linux-*.tar.bz2")
        if ! untar "$file"; then
            echo "Error unpacking MPSS kernel sources"
            return 1
        fi
        # Extract OFED headers
        file=$(find mpss-$ver -type f -path "*/ofed-driver-*-devel-*.rpm")
        if ! rpm2cpio "$file" | cpio -idm; then
            echo "Error extracting MPSS OFED headers"
            return 1
        fi
        # Remove unpacked archives to save space
        rm -rf mpss-$ver
        # Make link to MPSS kernel sources
        ln -sf linux-* mpss
    else
        local dir="mpss-${MPSS_VERSION}-${MPSS_DISTRO%%-*}"

        mkdir $dir || return 255
        pushd $dir >/dev/null || return 255
        if ! untar "$KERNELTREE/mpss_src-${MPSS_VERSION}-${MPSS_DISTRO}-part0.tar" "*/gpl/*full_src*"; then
            popd >/dev/null
            rm -rf $dir
            echo "Error unpacking MPSS tarball 1"
            return 1
        fi
        local file=$(find . -type f -path "*/gpl/*full_src*")
        if ! untar "$file"; then
            popd >/dev/null
            rm -rf $dir
            echo "Error unpacking MPSS tarball 2"
            return 1
        fi
        popd >/dev/null
        ln -sf $dir mpss
    fi

}

do_patch_linux() {

    local do_patch=${1:-true}

    FULL_PATCH="$PWD/lustre-kernel-${TARGET}-${EXTRA_VERSION}.patch"
    [ -f "$FULL_PATCH" ] && rm -f "$FULL_PATCH"
    $do_patch && pushd linux >/dev/null
    for series in $SERIES; do
        echo -n "Applying series $series:"
        for patchesdir in "$EXTERNAL_PATCHES" "$TOPDIR/lustre/lustre/kernel_patches"; do
            [ -r "$patchesdir/series/$series" ] || continue
            SERIES_FILE="$patchesdir/series/$series"
            for patch in $(<"$SERIES_FILE"); do
                echo -n " $patch"
                PATCH_FILE="$patchesdir/patches/$patch"
                [ -r "$PATCH_FILE" ] || \
                    fatal 1 "Patch $patch does not exist in Lustre tree."
                cat "$PATCH_FILE" >> "$FULL_PATCH" || {
                    rm -f $FULL_PATCH
                    fatal 1 "Error adding patch $patch to full patch."
                }
                if $do_patch; then
                    patch -s -p1 < "$PATCH_FILE" 2>&1 || {
                        rm -f $FULL_PATCH
                        fatal 1 "Error applying patch $patch."
                    }
                fi
            done
            break
        done
        echo
    done
    $do_patch && popd >/dev/null
    echo "Full patch has been saved in ${FULL_PATCH##*/}."

}

build_lustre() {
    local linux="$1"
    local linuxobj="$2"

    cp "$LUSTRE" SOURCES

    pushd lustre >/dev/null

    echo "Building Lustre RPMs for: $BUILD_ARCHS..."
    local targets arch
    for arch in $BUILD_ARCHS; do
        targets="--target $arch $targets"
    done

    local confoptions=""

    if $PATCHLESS; then
        confoptions="$confoptions --disable-server"
    fi

    local rpmbuildopt='-tb'
    if $NORPM; then
        rpmbuildopt='-tc'
        echo NORPM mode. Only compiling.
    fi

    # If server we now build the spl and zfs modules against the lustre kernel.
    # These are required prior to the building of lustre server. Client does
    # not require spl/zfs. Use !PATCHLESS to indicate server which follows the
    # line above so is at least consistant.
    if [ $PATCHLESS == false ] && [ "x$ZFSNOTSUPPORTED" == "x" ]; then
        if ! build_spl_zfs; then
            popd >/dev/null # pushd lustre
            return 255
        fi
    fi

    if $PATCHLESS; then
        RPMBUILD_DEFS="$RPMBUILD_DEFS --without servers"
        if [ -n "$CROSS_SUFFIX" ]; then
            RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"lustre_name lustre-client$CROSS_SUFFIX\""
        fi
    fi

    # ditto for the lustre-tests boolean
    if ! $LUSTRE_TESTS; then
        RPMBUILD_DEFS="$RPMBUILD_DEFS --without lustre_tests"
    fi

    if ! $IOKITRPM; then
        RPMBUILD_DEFS="$RPMBUILD_DEFS --without lustre_iokit"
    fi

    local osd_zfs=""
    if $OSDZFSRPM; then
        osd_zfs="yes"
    fi

    local osd_ldiskfs=""
    if $OSDLDISKFSRPM; then
        osd_ldiskfs="yes"
    fi

    RPMBUILD_DEFS="$RPMBUILD_DEFS ${FIND_REQUIRES:+--define \"__find_requires $FIND_REQUIRES\"}"
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"configure_args $confoptions ${CONFIGURE_FLAGS}\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"kdir $linux\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS ${linuxobj:+--define \"kobjdir $linuxobj\"}"
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"_tmppath $TMPDIR\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"_topdir $TOPDIR\""

    eval $RPMBUILD $targets $rpmbuildopt "$LUSTRE" $RPMBUILD_DEFS \
        ${osd_zfs:+--with zfs} \
        ${osd_ldiskfs:+--with ldiskfs} 2>&1 || \
        fatal 1 "Error building rpms for $BUILD_ARCHS."

    if $DO_SRC; then
        if ! eval $RPMBUILD -ts "$LUSTRE" $RPMBUILD_DEFS 2>&1; then
            popd >/dev/null
            return 255
        fi
    fi
    popd >/dev/null

}

###
# build_spl_zfs
#
# Fetch spl/zfs from the git repo and prepare for lustre build
#
# Overrides:
#   SPLZFSGITREPO - URI of directory where spl.git and zfs.git are located
#   SPLZFSTAG     - Tag to checkout of clone repositories
#   SPLZFSVER     - Version to checkout of both (format zfs/spl-$SPLZFSVER)
#
# return 0 if successful, else 255
build_spl_zfs() {
    # make sure the RPM build environment is set up
    pushd $TOPDIR
    create_rpmbuild_dirs
    popd

    # The spl/zfs spec files expect RPM_BUILD_ROOT to point to the root of the
    # destination for the rpms
    export RPM_BUILD_ROOT=$TOPDIR
    SPLZFSVER=${SPLZFSVER:-0.6.2}
    SPLZFSTAG=${SPLZFSTAG:-upstream-master}

    # The files expect a kver to be set to the kernel version .
    local kver=$(find_linux_release)

    # build and install the spl and zfs (and -devel) RPMs for lustre to use
    local pkg
    for pkg in spl zfs; do

        local rpmpkg

        [ "$pkg" == "zfs" ] && spldir="$(ls -d $TOPDIR/usr/src/spl-*/|tail -1)"

        # need to fetch the repo in order to build it.
        # default to github but allow override
        git clone ${SPLZFSGITREPO:-"https://github.com/zfsonlinux"}/$pkg.git $pkg 2>&1

        pushd $pkg || return 255
        if [ -n "$SPLZFSTAG" ]; then
            git checkout $SPLZFSTAG
        else
            git checkout -b lbuild $pkg-$SPLZFSVER
        fi

        # This differentiates between older zfs versions
        if [ -f $pkg-modules.spec.in ]; then
            rpmpkg=$pkg-modules
            specdir=.
            speclist="$pkg.spec $rpmpkg.spec"
        else
            rpmpkg=kmod-$pkg-devel
            specdir=rpm/generic
            speclist="$pkg.spec $pkg-kmod.spec $pkg-dkms.spec"
        fi

        sh autogen.sh || return 255

        if  ! ./configure --with-linux=${LINUX} --with-linux-obj=${LINUXOBJ:-$LINUX} \
                          ${spldir:+--with-spl="${spldir}"} 2>&1 ||
            ! make dist 2>&1; then
            popd
            return 255
        fi
        popd

        ln -f $pkg/$pkg-*.tar.gz $TOPDIR/SOURCES ||
           error "failed to link $pkg/$pkg-*.tar.gz into $TOPDIR/SOURCES"
        if [ -f $pkg/scripts/kmodtool ]; then
            ln -f $pkg/scripts/kmodtool $TOPDIR/SOURCES/
        fi

        local rpmb
        if $DO_SRC; then
            rpmb=-ba
        else
            rpmb=-bb
        fi

        # set search dir for our own kmodtool to find correct
        # directories
        export KERNELSOURCE=$(dirname ${LINUX})
        # Manually build rpms
        for spec in $speclist; do
            echo "Building RPMs from $pkg/$specdir/$spec"
            if ! $RPMBUILD $rpmb $pkg/$specdir/$spec \
                --nodeps -v \
                --define "require_kdir ${LINUX}" \
                ${LINUXOBJ:+--define "require_kobj ${LINUXOBJ}"} \
                ${spldir:+--define "require_spldir ${spldir}"} \
                --define "kver $kver" \
                --define "kernels $kver" \
                --define "_tmppath /var/tmp" \
                --define "kernelbuildroot $TOPDIR/reused" \
                --define "_topdir $TOPDIR" 2>&1; then
                return 255
            fi
        done

        # We have built the rpms for the package. Now we need to extract the
        # contained files so we can build further things against them
        local rpms=$(ls -1 $TOPDIR/RPMS/*/$rpmpkg-*.rpm)

        # cpio only extract to pwd so we need to go there.
        pushd $TOPDIR
        local rpm
        for rpm in $rpms; do
            rpm2cpio $rpm | cpio -id
        done

        if [ "$pkg" == "zfs" ]; then
            # We also need to extract both the zfs and zfs-devel rpms
            # the zfs rpm is needed because it has the actual libraries in
            # it and the zfs-devel rpm only has unversioned symlinks to the
            # libraries in the zfs rpm
            # this will all change one day when we have a libzfs rpm per
            # https://github.com/zfsonlinux/zfs/issues/2329
            # and it looks like it could be one day soon:
            # https://github.com/zfsonlinux/zfs/pull/2341
            local devel_rpms=$(ls -1 $TOPDIR/RPMS/*/{$pkg-devel,$pkg-$SPLZFSVER}-*.rpm)
            for rpm in $devel_rpms; do
                rpm2cpio $rpm | cpio -id
            done
            CONFIGURE_FLAGS="--with-$pkg-devel=$TOPDIR ${CONFIGURE_FLAGS}"
        fi
        popd

        CONFIGURE_FLAGS="--with-$pkg=$(ls -d $TOPDIR/usr/src/$pkg-*/|tail -1) ${CONFIGURE_FLAGS}"
        CONFIGURE_FLAGS="--with-$pkg-obj=$(ls -d $TOPDIR/usr/src/$pkg-*/$kver*|tail -1) ${CONFIGURE_FLAGS}"
    done

    OSDZFSRPM=true

    return 0
}

prepare_mpss() {

    pushd mpss >/dev/null || return 255
    if [ "${MPSS_VERSION%%.*}" = "3" ]; then
        cp -f ../boot/config-* .config
        if ! make ARCH=k1om silentoldconfig ; then
            popd >/dev/null
            return 1
        fi
        if ! make ARCH=k1om modules_prepare ; then
            popd >/dev/null
            return 1
        fi
        cp -f ../boot/Module.symvers-* Module.symvers
    else
        if ! make defconfig-miclinux; then
            popd >/dev/null
            return 1
        fi
        if ! make -C card/kernel ARCH=k1om modules_prepare ; then
            popd >/dev/null
            return 1
        fi
    fi
    popd >/dev/null

}

stage() {

    [ "$STAGEDIR" ] || return 0

    for arch in $BUILD_ARCHS; do
        rpmdir="${STAGEDIR}/${CANONICAL_TARGET}-${arch}"
        echo "${0##*/}: Copying RPMs into ${rpmdir}"
        mkdir -p "${rpmdir}"
        cp -v RPMS/${arch}/*.rpm "${rpmdir}"
        if [ -d RPMS/noarch ]; then
            cp -v RPMS/noarch/*.rpm "${rpmdir}"
        fi
    done

    cp -v "$LUSTRE" "$STAGEDIR"

}

set_rpm_smp_type() {

    local infact_arch="${TARGET_ARCH}"

    RPMSMPTYPE=""
    [ "$infact_arch" == "i586" ] && infact_arch="i686"

    local smp_type
    for smp_type in $SMP_ARCHS; do
        [ $infact_arch == $smp_type ] && RPMSMPTYPE=smp && break
    done

    for smp_type in $BIGSMP_ARCHS; do
        [ $infact_arch == $smp_type ] && RPMSMPTYPE=bigsmp && break
    done

    for smp_type in $PPC64_ARCHS; do
        [ $infact_arch == $smp_type ] && RPMSMPTYPE=ppc64 && break
    done

    for smp_type in $DEFAULT_ARCHS; do
        [ $infact_arch == $smp_type ] && RPMSMPTYPE=default && break
    done

}

# This function takes a linux include tree and digs out the linux release
# from it. It is never called directly, only called from the distro
# specific function find_linux_release() in lbuild-{rhel,sles}.
_find_linux_release() {
    local SRC="$1"
    local LINUXRELEASEHEADER=""

    LINUXRELEASEHEADER=$SRC/include/linux/version.h
    if [ -s $SRC/include/generated/utsrelease.h ]; then
        LINUXRELEASEHEADER=$SRC/include/generated/utsrelease.h
    elif [ -s $SRC/include/linux/utsrelease.h ]; then
        LINUXRELEASEHEADER=$SRC/include/linux/utsrelease.h
    fi

    if [ ! -s $LINUXRELEASEHEADER ]; then
        fatal 1 "could not find UTS_RELEASE"
    fi

    sed -ne 's/#define UTS_RELEASE "\(.*\)"$/\1/p' $LINUXRELEASEHEADER
}

# unpack kernel(/source/devel) RPM
#
# This function and it's setting of $LINUX and $LINUXOBJ is a total hack that
# needs to completely refactored.  It completely ingores that $BUILD_ARCHS may
# contain a list of arches for which rpmbuild commands (including the one for
# lustre itself)
unpack_linux_devel_rpm() {
    local kernelrpm="${1}"

    [ -f "$kernelrpm" ] || return 255
    [ -d $TOPDIR/reused ] || mkdir $TOPDIR/reused || return 255

    pushd $TOPDIR/reused &>/dev/null || return 255

    if ! rpm2cpio < "$kernelrpm" | cpio -id > /dev/null 2>&1; then
        return 255
    fi

    # call a distro specific hook, if available
    if type -p unpack_linux_devel_rpm-$DISTRO; then
        if ! unpack_linux_devel_rpm-$DISTRO "$kernelrpm"; then
            return 255
        fi
    fi

    popd &>/dev/null

    find_linux_devel_paths $TOPDIR/reused

    return 0

}

build_kernel_ib() {
    local linux="$1"
    local kib_prefix="$2"
    local kib_rpm="$3"

    # build kernel-ib{,-devel}/compat-rdma{,-devel}
    local K_SRC="K_SRC"
    # ofed 1.3 had a bug in the rpm spec
    if [ "$OFED_VERSION" = "1.3" ]; then
        K_SRC="KSRC"
    fi

    local OFED_CORE="--with-core-mod --with-ipoib-mod --with-sdp-mod --with-user_mad-mod --with-user_access-mod --with-addr_trans-mod"
    local OFED_HARDWARE="--with-mthca-mod --with-mlx4-mod --with-mlx4_en-mod --with-cxgb3-mod --with-nes-mod"

    if compare_version $OFED_VERSION 3.0; then
	OFED_CORE="$OFED_CORE --with-madeye-mod --with-rds-mod"
    else
	OFED_HARDWARE="$OFED_HARDWARE --with-cxgb4-mod"
    fi

    # some I/B drivers are architecture dependent and kernel-ib's configure
    # does not figure it out for us ~sigh~
    case "$TARGET_ARCH" in
        ppc64)
            OFED_HARDWARE="$OFED_HARDWARE --with-ehca-mod"
            ;;
    esac
    # we're no longer shipping the OFED iSCSI target
    #OFED_ISCSI="--with-srp-mod --with-srp-target-mod"
    OFED_ISCSI="--with-srp-mod"
    ## ISER module has no backport support as of OFED 1.5 (i.e. only builds on
    ##kernels >= 2.6.30)
    #if [[ $OFED_VERSION = 1.[0-4]* ]]; then
    #   OFED_ISCSI="$OFED_ISCSI --with-iser-mod"
    #fi

    # assume we are just rebuilding the SRPM
    local BUILD_TYPE=${BUILD_TYPE:-"--rebuild"}
    local SOURCE="${TOPDIR}/OFED/SRPMS/${kib_prefix}-*.src.rpm"

    # but switch to building from the SPEC if we need to apply patches
    if ls ${TOPDIR}/lustre/contrib/patches/ofed/* >/dev/null; then
        BUILD_TYPE="-bb"
        rpm --define "_topdir ${TOPDIR}" -ivh $SOURCE
        SOURCE="${TOPDIR}/SPECS/${kib_prefix}.spec"
        local file ed_fragment1 ed_fragment2 n=1
        for file in $(ls ${TOPDIR}/lustre/contrib/patches/ofed/*.patch); do
            ed_fragment1="$ed_fragment1
Patch$n: ${file%%*/}"
            ed_fragment2="$ed_fragment2
%patch$n -p0"
            cp $file ${TOPDIR}/SOURCES
            let n=$n+1
        done
        for file in $(ls ${TOPDIR}/lustre/contrib/patches/ofed/*.ed); do
            # Only apply the ed-scripts that should be used for the canonical target
            # ed-files in ${TOPDIR}/lustre/contrib/patches/ofed/ have to follow the naming
            # convention
            # <two-digits>-<descriptive-name>:<canonical_target_1>: ...:<canonical_target_N>.ed
            # To apply the same change to multiple canonical target simply specify
            # a list of colon separated canoncial target names in the file name.
            echo "$file" | grep -q -e ":${CANONICAL_TARGET}:" \
                                   -e ":${CANONICAL_TARGET}.ed$"
            if [ $? -eq 0 ] ; then
                ed_fragment3="$ed_fragment3
$(cat $file)"
                let n=$n+1
            fi
        done

        if [ $n -gt 1 ]; then
            ed $SOURCE <<EOF
/^Source: /a
$ed_fragment1
.
/^%setup /a
$ed_fragment2
.
$ed_fragment3
wq
EOF
        fi
    fi

    local linuxrelease=$(find_linux_release)
    if compare_version $OFED_VERSION 3.0; then
        local OFA_KERNEL_RELEASE=$(echo -n ${linuxrelease} | sed -e 's/-/_/g')
    fi
    if ! $RPMBUILD $BUILD_TYPE --define 'build_kernel_ib 1' --define 'build_kernel_ib_devel 1' \
                  ${FIND_REQUIRES:+--define "__find_requires $FIND_REQUIRES"} \
                  --define "_topdir ${TOPDIR}" --target ${TARGET_ARCH} \
                  --define "KVERSION ${linuxrelease}" \
                  --define "$K_SRC ${linux}" \
                  --define "LIB_MOD_DIR /lib/modules/${linuxrelease}/updates" \
                  ${OFA_KERNEL_RELEASE:+--define "_release $OFA_KERNEL_RELEASE"} \
                  --define "configure_options --without-quilt $OFED_CORE $OFED_HARDWARE $OFED_ISCSI" \
                  ${SOURCE} 2>&1; then
        fatal 1 "Error building ${kib_rpm}"
    fi

}

store_for_reuse() {
    local articles="$1"
    local module="$2"
    local location="$3"
    local signature="$4"
    local use_links="$5"

    local linkflag=""
    if $use_links; then
        linkflag="l"
    fi

    local default_iface=$(/sbin/ip route get 192.1.1.1 | sed -ne 's/.* dev \(.*\)  * src .*/\1/p')
    if [ -z "$default_iface" ]; then
        fatal 1 "Failed to determine the default route interface"
    fi
    local unique_id=$(/sbin/ip addr show dev $default_iface | sed -ne '/ inet /s/ *inet \(.*\)\/.*/\1/p' | head -1)
    if [ -z "$unique_id" ]; then
        fatal 1 "Failed to determine a unique id from interface $default_interface"
    fi

    local finallocation="$location"/"$signature"/"$module"
    location="$location"/"$signature-${unique_id}"/"$module"
    mkdir -p "$location"
    # the cleanup script removes any directory that doesn't have a
    # .lastused, so let's try to prevent that as soon as we can
    # this solution still slightly racy with the cleanup script
    # but the race is a lot tighter now
    touch -t 197001010000 "$location/.lastused"
    ## use eval/echo here to make sure shell expansions are performed
    #if ! cp -a${linkflag} $(eval echo $articles) "$location"; then
    local article
    for article in $(eval echo $articles); do
        if ! cp -a${linkflag} "$article" "$location"; then
            error "Failed to copy \"$article\" to \"$location\" in store_for_reuse()"
            # rename the cache location so that it's not cached
            # product, but is around for analysis
            mv "$location"{,-bad-$(date +%s)} ||
                error "failed to clean up a failed cache attempt" \
                      "in \"$location\" -- manual cleanup will be" \
                      "necessary"
            return 1
        fi
    done

    # flag the cache as complete (i.e. in case lbuild was previously
    # interrupted while caching)
    touch "$location/.lastused"

    # put the temporary location into the final location
    # (last one wins)
    mkdir -p "${finallocation%/*}"
    mv "$location" "$finallocation"
    rmdir "${location%/*}"
    return 0

}

reuse() {
    local module="$1"
    local dest="$2"
    local use_links="${3:-false}"
    local signature="$4"

    if [ -n "$REUSEBUILD" ] && [ -d "$REUSEBUILD/$signature/$module" ]; then
        if [ ! -f "$REUSEBUILD/$signature/$module/.lastused" ]; then
            # the .lastused flag is populated at the end of the caching to
            # signal that the caching was completed.  if that flag is not
            # there, then the cache is invalid (and should be removed in fact)
            mv "$REUSEBUILD/$signature/$module"{,-bad-$(date +%s)} ||
                fatal 1 "failed to clean up a bad cache in location $REUSEBUILD/$signature/$module\" -- manual cleanup will be necessary"
            return 1
        fi

        # so that we know how stale this entry is
        touch $REUSEBUILD/$signature/$module/.lastused

        if $use_links; then
            if ls $REUSEBUILD/$signature/$module/* >/dev/null 2>&1; then
                cp -al $REUSEBUILD/$signature/$module/* $dest/
            fi
        else
            # copying is pretty heavy
            # cp -a $REUSEBUILD/$signature/$module/* $dest/
            # do some creative symlinking instead
            local dir
            for dir in BUILD SRPMS SPECS; do
                if ls $REUSEBUILD/$signature/$module/$dir/* >/dev/null 2>&1; then
                    ln -s $REUSEBUILD/$signature/$module/$dir/* $dest/$dir
                fi
            done
            # sources have to be copied by file because we need SOURCES to
            # be a dir we can write into
# could overrun ls's arg list here
            #ls $REUSEBUILD/$signature/$module/SOURCES/* |
            find $REUSEBUILD/$signature/$module/SOURCES/ -type f |
                xargs ln -t $dest/SOURCES -s

            # same for RPMS/* dirs
# could overrun ls's arg list here
            #ls $REUSEBUILD/$signature/$module/RPMS/$TARGET_ARCH/* |
            local dir
            for dir in $REUSEBUILD/$signature/$module/RPMS/*; do
                mkdir -p $dest/RPMS/${dir##*/}
                find $dir -type f |
                  xargs ln -t $dest/RPMS/${dir##*/} -s
            done
        fi
        return 0
    else
        return 1
    fi
}

basearch() {
    local arch="$1"

    if [[ $arch = i[3456]86 ]]; then
        echo "i386"
    else
        echo "$arch"
    fi

}

build_kernel_with_srpm() {
    local outfd=$1

    if [ -z "$outfd" ] || [ $outfd = 1 ]; then
        fatal 1 "You must supply a file descriptor to ${FUNCNAME[0]} and it cannot be 1"
    fi

    # need to generate the patch for this target
    do_patch_linux false >&${outfd}    # sets global $FULL_PATCH (yeah, yuck)

    # get an md5sum of the kernel patch + config for reuse check
    # XXX really, there needs to be a signature and a CONFIG_FILE per arch
    #     in BUILD_ARCHS
    local release_str
    if $RELEASE; then
        local release_str="RELEASE=$RELEASE\n"
    fi

    if $USE_BUILD_CACHE && [ -n "$REUSEBUILD" ]; then
        local REUSE_SIGNATURE=$({ echo -en $release_str;
                                  echo $BUILD_GEN;
                                  cat $CONFIG_FILE $TARGET_FILE $FULL_PATCH;
                                  cat $LBUILD_DIR/lbuild $LBUILD_DIR/lbuild-${DISTRO}; } |
                                md5sum | cut -d" " -f1)
        # see if we can link to the reuse pool
        # XXX - hrm.  i'm not convinced this doesn't belong in the reuse
        #       "library"
        local CAN_LINK_FOR_REUSE=false
        touch $REUSEBUILD/$$
        if cp -al $REUSEBUILD/$$ $TOPDIR/ 2>/dev/null; then
            CAN_LINK_FOR_REUSE=true
        fi
        rm $REUSEBUILD/$$
    fi

    # the extra version string to use for the kernel (which might be a reused
    # kernel, remember)
    local kernel_extra_version=""
    if ! $USE_BUILD_CACHE || ! reuse kernel "$TOPDIR" "$CAN_LINK_FOR_REUSE" \
                                   "$REUSE_SIGNATURE"; then
        # nothing cached, build from scratch
        if [ ! -r "$KERNELDIR/$KERNEL_SRPM" ]; then
            echo "Downloading kernel SRPM" >&${outfd}
            download_srpm "$CANONICAL_TARGET" "$KERNEL_SRPM" >&${outfd}
        fi

        if ! rpm -ivh $KERNELDIR/$KERNEL_SRPM \
                  --define "_topdir $TOPDIR" >&${outfd} 2>&1; then
            # should we clean this up or leave it for analysis?
            #rm -rf $RPMTOPDIR
            fatal 1 "Error installing kernel SRPM."
        fi

        # put the Lustre kernel patch into the RPM build tree
        cp $FULL_PATCH $TOPDIR/SOURCES/linux-${lnxmaj}-lustre.patch
        prepare_and_build_srpm >&${outfd} ||
            fatal 1 "failed to prepare_and_build_srpm"

        if [ -z "$REUSE_SIGNATURE" ]; then
            echo "No reuse signature was caculated so not storing the built kernel" >&${outfd}
        else
            # store the resulting kernel RPM build tree for future use
            echo "Storing the built kernel for future reuse" >&${outfd}
            if ! store_for_reuse "$TOPDIR/{SPECS,SOURCES,SRPMS,RPMS}" \
                                 "kernel" "$REUSEBUILD" "$REUSE_SIGNATURE" \
                                 "$CAN_LINK_FOR_REUSE"; then
                error "Failed to store kernel RPMS for reuse"
                echo "unknown" >&${outfd}
                return 1
            fi
        fi
    fi  # build reuse

    # figure out the EXTRA_VERSION of the kernel we built or are re-using
    local KERNEL_RPM
    if ! KERNEL_RPM=$(find_rpm "$TOPDIR/RPMS/$TARGET_ARCH/" provides "^kernel(-default)? ="); then
        fatal 1 "Failed to find a kernel RPM in $TOPDIR/RPMS/$TARGET_ARCH/"
    fi
    kernel_extra_version=$(rpm -q --queryformat "%{RELEASE}" -p $TOPDIR/RPMS/$TARGET_ARCH/$KERNEL_RPM)

    # should now have the following RPMs
    # $TOPDIR/RPMS/$arch/kernel-lustre-2.6.18-53.1.21.el5_lustre.1.6.5.1.$arch.rpm
    # $TOPDIR/RPMS/$arch/kernel-lustre-devel-2.6.18-53.1.21.el5_lustre.1.6.5.1.$arch.rpm
    # $TOPDIR/RPMS/$arch/kernel-lustre-headers-2.6.18-53.1.21.el5_lustre.1.6.5.1.$arch.rpm
    # $TOPDIR/RPMS/$arch/kernel-lustre-debuginfo-common-2.6.18-53.1.21.el5_lustre.1.6.5.1.$arch.rpm
    # $TOPDIR/RPMS/$arch/kernel-lustre-debuginfo-2.6.18-53.1.21.el5_lustre.1.6.5.1.$arch.rpm

    echo $kernel_extra_version
    return 0

}

# build OFED
# globals used:
#    TOPDIR
#    REUSEBUILD, USE_BUILD_CACHE
#    CONFIGURE_FLAGS

build_ofed() {
    local linux="$1"
    local ofed_version="$2"
    local kib_prefix
    local kib_rpm

    # if an ofed version is given, then it means use OFED proper,
    # not any vendor specific "inkernel" version
    if [ -z "$ofed_version" ]; then
        return 0
    fi

    if [ "$ofed_version" = "inkernel" ]; then
        # see if there is a distro specific override for this and use
        # that if it exists
        # XXX we need to better integrate a distro specific override with
        #     the rest of this function so that all of the reuse cache
        #     stuff is leveraged given that 80% of this function is reuse
        if type -p build_ofed-${DISTRO}; then
            local ofed_location
            ofed_location=$(build_ofed-${DISTRO} ${STDOUT})
            local rc=${PIPESTATUS[0]}
            CONFIGURE_FLAGS="--with-o2ib=${ofed_location} ${CONFIGURE_FLAGS}"
            return $rc
        else
            return 0
        fi
    elif compare_version $OFED_VERSION 3.0; then
	kib_prefix="ofa_kernel"
	kib_rpm="kernel-ib"
    else
	kib_prefix="compat-rdma"
	kib_rpm="compat-rdma"
    fi

    # build kernel-ib/compat-rdma
    if $USE_BUILD_CACHE && [ -n "$REUSEBUILD" ]; then
        local REUSE_SIGNATURE=$({ echo "$ofed_version";
                                  echo "$(find_linux_release;
                                  echo "$BUILD_GEN")";
                                  cat "${linux}/include/linux/autoconf.h";
                                  cat "$LBUILD_DIR/lbuild" ;
                                  cat "$LBUILD_DIR/lbuild-${DISTRO}"; } |
                                md5sum | cut -d" " -f1)
        # see if we can link to the reuse pool
        # XXX - hrm.  i'm not convinced this doesn't belong in the reuse
        #       "library"
        local CAN_LINK_FOR_REUSE=false
        touch $REUSEBUILD/$$
        if cp -al $REUSEBUILD/$$ $TOPDIR/; then
            CAN_LINK_FOR_REUSE=true
        fi
        rm $REUSEBUILD/$$
    fi

    if ! $USE_BUILD_CACHE || ! reuse ofed "$TOPDIR" "$CAN_LINK_FOR_REUSE" \
                                   "$REUSE_SIGNATURE"; then
        if [ -n "$REUSE_SIGNATURE" ]; then
            # stash away the existing built articles for a moment
            mkdir bak
            mv {BUILD,{S,}RPMS,S{OURCE,PEC}S} bak
            function mv_back {
                pushd bak
                find . | cpio -pudlm ..
                popd
                rm -rf bak
            }
            create_rpmbuild_dirs
        fi
        # build it
        build_kernel_ib "${linux}" "${kib_prefix}" "${kib_rpm}"

        if [ -z "$REUSE_SIGNATURE" ]; then
            echo "No reuse signature was caculated so not storing the built ofed"
        else
            # store the resulting RPM build tree for future use
            echo "Storing the built ofed for future reuse"
            if ! store_for_reuse "$TOPDIR/{SPECS,SOURCES,BUILD,SRPMS,RPMS}" \
                                 "ofed" "$REUSEBUILD" "$REUSE_SIGNATURE" \
                                 "$CAN_LINK_FOR_REUSE"; then
                error "Failed to store OFED RPMS for reuse"
                mv_back
                return 1
            fi
            # put the stuff we stashed away back
            mv_back
        fi
    fi

    pushd "$TOPDIR" >/dev/null
    rm -rf ${kib_rpm}-devel
    mkdir ${kib_rpm}-devel
    cd ${kib_rpm}-devel
    # the actual ofed RPMs don't have the -rc$n or -$date string appened that
    # might be present on the file
    #local linuxrelease=$(find_linux_release)
    #ofed_version=$(echo $ofed_version |
    #               sed -re 's/-(20[0-9]{6,6}-[0-9]{4,4}|rc[0-9]*)$//')
    # FIXME
    # OFED version will have 'hyphen' for minor release. (e.g. 3.5-1, instead
    # of 3.5.1) compat-rdma and compat-rdma-devel could have same version
    # number, but currectly not. Once OFED fix this in the future release, we
    # can remove following filter.
    #ofed_version=$(echo $ofed_version |
    #               sed -re 's/-([0-9]*-[rR][cC][0-9]*)$//')
    #local rpm=$(ls $TOPDIR/RPMS/*/${kib_rpm}-devel-${ofed_version}-${linuxrelease//-/_}.*.rpm)
    # I dont' know why we have gone through the trouble to filter out the name
    # of the rpm there should only be one ${kib_rpm}-devel built
    local rpm=$(ls $TOPDIR/RPMS/*/${kib_rpm}-devel-*.rpm)
    if ! rpm2cpio < $rpm | cpio -id; then
        fatal 1 "could not unpack the ${kib_rpm}-devel rpm."
    fi
    CONFIGURE_FLAGS="--with-o2ib=$(pwd)/usr/src/${kib_prefix} ${CONFIGURE_FLAGS}"
    popd >/dev/null

}

build_with_srpm() {

    if ! $PATCHLESS; then
        local kernel_extra_version
        if ! kernel_extra_version=$(build_kernel_with_srpm ${STDOUT}); then
            fatal 1 "Failed to build the kernel from it's SRPM"
        fi

        for arch in $BUILD_ARCHS; do
            local kernel_devel_rpm
            if ! kernel_devel_rpm=$(find_rpm "$TOPDIR/RPMS/$arch/" provides "^$(devel_kernel_name $KERNEL_LUSTRE_NAMING) ="); then
                fatal 1 "Failed to find a kernel development RPM in $TOPDIR/RPMS/$arch/"
            fi

            # install the -devel RPM in preparation for modules builds
            if ! lnxrel="$kernel_extra_version" unpack_linux_devel_rpm \
                           "$TOPDIR/RPMS/$arch/$kernel_devel_rpm"; then
                fatal 1 "Could not find the Linux tree in $TOPDIR/RPMS/$arch/$kernel_devel_rpm"
            fi
        done
    else
        # need to find and unpack the vendor's own kernel-devel for patchless
        # client build
        local kernelrpm
        if ! kernelrpm=$(find_linux_rpm "-$DEVEL_KERNEL_TYPE"); then
            fatal 1 "Could not find the kernel-$DEVEL_KERNEL_TYPE RPM in ${KERNELRPMSBASE}/${lnxmaj}/${DISTRO}"
        fi
        if ! lnxrel="$lnxrel" unpack_linux_devel_rpm "$kernelrpm" "-"; then
            fatal 1 "Could not find the Linux tree in $kernelrpm"
        fi
    fi

    # ~sigh~  have to make copies of and modify some of the rpm
    # infrastructure files so that find-requires can find our unpacked
    # kernel-devel artifacts
    cp $RPM_HELPERS_DIR/{symset-table,find-requires{,.ksyms}} .
    FIND_REQUIRES="$(pwd)/find-requires"
    chmod 755 {symset-table,find-requires{,.ksyms}}
    local tmp="$(pwd)"
    tmp="${tmp//\//\\/}"
    ed find-requires <<EOF
1a
set -x
.
/|.*find-requires.ksyms/s/|/| bash -x/
g/ [^ ]*\/\(find-requires\.ksyms\)/s// $tmp\/\1/g
wq
EOF
    ed find-requires.ksyms <<EOF
1a
set -x
.
g/\/.*\/\(symset-table\)/s//$tmp\/\1/g
wq
EOF
    ed symset-table <<EOF
1a
set -x
.
g/\(\/boot\/\)/s//$tmp\/reused\1/g
g/\(\/usr\/src\/kernels\/\)/s//$tmp\/reused\1/g
wq
EOF

    build_ofed "${LINUXOBJ:-$LINUX}" "$OFED_VERSION" ||
        fatal 1 "error building OFED"

    # now build Lustre
    if build_lustre "$LINUX" "$LINUXOBJ"; then
        # the build worked.  resolve any symlinked files (i.e. from reuse)
        # in RPMS/$arch to real files so that that that huge mess of
        # complication known as LTS can copy them yet somewhere else.
        # is it any wonder this whole process is so damn so?  anyone ever
        # heard of hardlinks?  it's this cool new thing that allows you save
        # tons of time and space by creating... well you can go read about
        # them if you have not heard about them yet.
        # can i say how much the implemenation of all of this really impedes
        # RPM reuse?
        local dir
        for dir in RPMS/*; do
            pushd $dir
            for file in $(ls); do
                if [ -h $file ]; then
                    cp $file foo
                    mv foo $file
                fi
            done
            popd
        done
        # also, for i?86, make sure all of the RPMs are in RPMS/$TARGET_ARCH
        # as that's where LTS expects to find them
        for dir in RPMS/*; do
            if [ $dir = RPMS/$TARGET_ARCH ]; then
                continue
            fi
            pushd $dir
            local files=$(ls)
            if [ -n "$files" ]; then
                cp -al $files ../$TARGET_ARCH
            fi
            popd
        done
    else
        return 1
    fi

}

create_rpmbuild_dirs() {

    [ -d RPMS ] || mkdir RPMS
    for arch in $BUILD_ARCHS; do
        if [[ $arch = i?86 ]]; then
            # some stupidity in the sles11 kernel spec requires an RPMS/i386
            # even if the target arch is i686
            [ -d RPMS/i386 ] || mkdir RPMS/i386
        fi
        [ -d RPMS/$arch ] || mkdir RPMS/$arch
    done
    [ -d RPMS/noarch ] || mkdir RPMS/noarch
    [ -d BUILD ] || mkdir BUILD
    [ -d SOURCES ] || mkdir SOURCES
    [ -d SPECS ] || mkdir SPECS
    [ -d SRPMS ] || mkdir SRPMS

}

new_list() {

    echo ""

}

add_list() {
    local list="$1"
    local item="$2"

    echo "$list $item"

}

is_list_member() {
    local list="$1"
    local item="$2"

    [[ $list\  == *\ $item\ * ]]

}

#########################################################################
# Generate a backtrace through the call stack.
#
# Input: None
# Output: None
#########################################################################
backtrace() {
    local strip=${1:-1}

    local funcname="" sourcefile="" lineno="" n

    echo "Call stack: (most recent first)"
    for (( n = $strip ; n < ${#FUNCNAME[@]} ; ++n )) ; do
        funcname=${FUNCNAME[$n - 1]}
        sourcefile=$(basename ${BASH_SOURCE[$n]})
        lineno=${BASH_LINENO[$n - 1]}
        if [ $n = 1 ]; then
            let lineno-=11
        fi
        # Display function arguments
        if [[ ! -z "${BASH_ARGV[@]}" ]]; then
            local args newarg j p=0
            for (( j = ${BASH_ARGC[$n - 1]}; j > 0; j-- )); do
                newarg=${BASH_ARGV[$j + $p - 1]}
                args="${args:+${args} }'${newarg}'"
            done
            let p+=${BASH_ARGC[$n - 1]}
        fi
        echo "  ${funcname} ${args:+${args} }at ${sourcefile}:${lineno}"
    done

    echo
    echo "BEGIN BACKTRACE"

    #echo ${BASH_LINENO[*]}
    #echo ${BASH_SOURCE[*]}
    #echo ${FUNCNAME[*]}
    local i=$((${#FUNCNAME[@]} - 1))
    while [ $i -ge 0 ]; do
        local lineno=${BASH_LINENO[$i]}
        if [ $i = 0 ]; then
            let lineno-=11
        fi
        local SOURCELINE="${BASH_SOURCE[$i + 1]}:${lineno}"
        # Can't figure out how to get function args from other frames...
        local FUNCTION="${FUNCNAME[$i]}()"
        echo "$SOURCELINE:$FUNCTION"
        i=$((i - 1))
    done

    echo "END BACKTRACE"

    echo $BACKTRACE

}

seen_list=$(new_list)
trap 'set +x;
echo "An unexpected error has occurred at ${BASH_SOURCE[0]##*/}:$((LINENO-1)).
Unfortunately the above line number in the message may or may not be correct,
but details have been send to the lbuild maintainer.  Attempting to continue."; (echo "Untrapped error"
echo
# have we seen this one
echo "checking seen list for ${BASH_SOURCE[0]}:${BASH_LINENO[0]}"

if is_list_member "$seen_list" "${BASH_SOURCE[0]}:${BASH_LINENO[0]}"; then
  echo "seen this one already"
else
  seen_list=$(add_list "$seen_list" "${BASH_SOURCE[0]}:${BASH_LINENO[0]}")
fi
backtrace
) ; set $xtrace' ERR
set -E

[ -r ~/.lbuildrc ] && . ~/.lbuildrc

options=$(getopt -o D:h -l kerneltree:,distro:,kernelrpm:,reusebuild:,patchless,ldiskfs,ccache,reuse:,norpm,disable-datestamp,external-patches:,timestamp:,extraversion:,kerneldir:,linux:,lustre:,nodownload,nosrc,noiokit,ofed-version:,mpss-version:,publish,release,set-value:,src,stage:,tag:,target:,target-archs:,with-linux:,xen -- "$@")

if [ $? != 0 ]; then
    usage 1
fi

eval set -- "$options"

while [ "$1" ]; do
    case "$1" in
        '')
            usage 1
            ;;
        --ccache)
            CCACHE='ccache'
            shift
            ;;
        -D)
            DATE=$2
            shift 2
            ;;
        --external-patches)
            EXTERNAL_PATCHES=$2
            shift 2
            ;;
        --extraversion)
            EXTRA_VERSION=$2
            shift 2
            ;;
        --help | -h)
            usage 0
            ;;
        --kerneldir)
            KERNELDIR=$2
            shift 2
            ;;
        --kerneltree)
            if ! KERNELTREE=$(canon_path "$2"); then
                fatal 1 "Could not determine the canonical location of $2"
            fi
            shift 2
            ;;
        --linux | --with-linux)
            if ! LINUX=$(canon_path "$2"); then
                fatal 1 "Could not determine the canonical location of $2"
            fi
            shift 2
            ;;
        --distro)
            DISTRO=$2
            shift 2
            ;;
        --reuserpm)
            REUSERPM=$2
            shift 2
            ;;
        --reusebuild)
            if ! REUSEBUILD=$(canon_path "$2"); then
                fatal 1 "Could not determine the canonical location of $2"
            fi
            shift 2
            ;;
        --norpm)
            NORPM=true
            shift
            ;;
        --ldiskfs)
	    echo "WARNING: \"--ldiskfs\" is deprecated" > 2
            shift
            ;;
        --noiokit)
            IOKITRPM=false
            shift
            ;;
        --patchless)
            PATCHLESS=true
            shift
            ;;
        --kernelrpm)
            if ! KERNELRPMSBASE=$(canon_path "$2"); then
                fatal 1 "Could not determine the canonical location of $2"
            fi
            shift 2
            ;;
        --timestamp)
            TIMESTAMP=$2
            shift 2
            ;;
        --lustre)
            if ! LUSTRE=$(canon_filepath "$2"); then
                fatal 1 "Could not determine the canonical location of $2"
            fi
            shift 2
            ;;
        --nodownload)
            DOWNLOAD=false
            shift 1
            ;;
        --nosrc)
            DO_SRC=false
            shift 1
            ;;
        --ofed-version)
            OFED_VERSION="$2"
            shift 2
            ;;
        --mpss-version)
            MPSS_VERSION="$2"
            shift 2
            ;;
        --publish)
            shift
            ;;
        --release)
            RELEASE=true
            shift
            ;;
        --src)
            DO_SRC=true
            shift 1
            ;;
        --stage)
            STAGEDIR=$2
            shift 2
            ;;
        --tag)
            shift 2
            echo "WARNING: \"--tag\" is deprecated" > 2
            ;;
        --target)
            TARGET=$2
            shift 2
            ;;
        --target-archs)
            TARGET_ARCHS=$2
            shift 2
            ;;
        --xen)
            XEN=true
            shift
            ;;
        --set-value)
            eval $2
            shift 2
            ;;
        --)
            shift
            # there are actually some lustre configure flags that we need to
            # handle ourselves (but we still give them to configure)
            if [[ \ $@\  == *\ --disable-tests\ * ]]; then
                LUSTRE_TESTS=false
            fi
            CONFIGURE_FLAGS=$@
            break
            ;;
        *)
            usage 1 "Unrecognized option: $1"
            ;;
    esac
done

check_options

unpack_lustre

# XXX - should we _always_ get the buildid from the META file?  what are the
# other (i.e. non-lustre-tarball use cases of lbuild)?
BUILDID=$(sed -ne '/^BUILDID =/s/.*= *//p' lustre/META)
VERSION=$(sed -ne '/^VERSION =/s/.*= *//p' lustre/META)

load_target

if [ -n "$OFED_VERSION" -a "$OFED_VERSION" != "inkernel" ]; then
    download_ofed
    unpack_ofed || fatal 1 "Error unpacking OFED tarball"
fi

if [ -n "$MPSS_VERSION" ]; then
    [ -z "$MPSS_DISTRO" ] && MPSS_DISTRO=$(autodetect_distro)

    MPSS_INFO=$(mktemp -u mpss-info-XXXXXXXXXX.html)
    download_mpss_info "$MPSS_INFO"

    if [ "$MPSS_VERSION" = "last" ]; then
        MPSS_VERSION=$(parse_mpss_info "$MPSS_INFO" "" ${MPSS_DISTRO})
        [ -z "$MPSS_VERSION" ] && fatal 1 "Could not determine the last MPSS version"
    elif [[ $MPSS_VERSION != [0-9].[0-9].[0-9]*-[0-9]* ]]; then
        fatal 1 "Incorrect MPSS version $MPSS_VERSION"
    fi

    download_mpss "$MPSS_INFO"
    [ -r "$MPSS_INFO" ] && rm -f "$MPSS_INFO"
    echo "Building with MPSS $MPSS_VERSION"
    unpack_mpss  || fatal 1 "Error unpacking MPSS tarballs"
    prepare_mpss || fatal 1 "Error preparing MPSS for kernel modules build"

    if [ -z "$MPSS_OFED" ]; then
        MPSS_OFED=$(find $PWD -type f -path "*/ofed-driver-*/Module.symvers")
        if [ -n "$MPSS_OFED" ]; then
            MPSS_OFED="--with-o2ib=$(dirname $MPSS_OFED)"
        else
            MPSS_OFED="--without-o2ib"
        fi
    fi

    # disable unsupported parts:
    PATCHLESS=true
    IOKITRPM=false
    LDISKFSRPM=false
    ZFSNOTSUPPORTED="yes"

    # define variables for cross compilation:
    CROSS_SUFFIX="-mic"
    if [ "${MPSS_VERSION%%.*}" = "3" ]; then
        CC_TARGET_ARCH=k1om-mpss-linux
        LINUX="$TOPDIR/mpss"
    else
        CC_TARGET_ARCH=x86_64-k1om-linux
        LINUX="$TOPDIR/mpss/card/kernel"
        RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"cross_requires intel-mic-gpl = ${MPSS_VERSION%%-*}\""
    fi
    CONFIGURE_FLAGS="$CONFIGURE_FLAGS $MPSS_OFED --host=$CC_TARGET_ARCH --build=x86_64-pc-linux"
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"post_script build/gen_filelist.sh\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"make_args ARCH=k1om CROSS_COMPILE=${CC_TARGET_ARCH}-\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"cross_path ${CROSS_PATH:=/opt/lustre/${VERSION}/${CC_TARGET_ARCH}}\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"rootdir %{cross_path}\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"_prefix %{cross_path}/usr\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"_mandir %{_prefix}/share/man\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"_sysconfdir %{cross_path}/etc\""
    RPMBUILD_DEFS="$RPMBUILD_DEFS --define \"kmoddir extra\""

    # redefine CC for proper ./configure during rpmbuild
    export CC=${CC_TARGET_ARCH}-gcc
fi

# make sure the RPM build environment is set up
create_rpmbuild_dirs

# if an unpacked kernel source tree was given on the command line
# just build lustre with it (nothing distro kernel specific here)
if [ -n "$LINUX" ]; then
    find_linux_release() {
        _find_linux_release $LINUX
    }
    build_ofed "${LINUXOBJ:-$LINUX}" "$OFED_VERSION" ||
        fatal 1 "error building OFED"
    build_lustre "$LINUX" "$LINUXOBJ"
else
    if [ ! -f "${LBUILD_DIR}/lbuild-$DISTRO" ]; then
        fatal 1 "${LBUILD_DIR}/lbuild-$DISTRO not found"
    fi
    source ${LBUILD_DIR}/lbuild-$DISTRO
    build_with_srpm || fatal 1 "Failed to build_with_srpm"
fi

stage