#! /bin/bash

# mk-basefile, create basefiles for some distributions
#
# Thomas Lange, Uni Koeln, 2011-2016
# based on the Makefile implementation of Michael Goetze

# Supported distributions (each i386/amd64):
# Debian GNU/Linux
# Ubuntu 14.04/16.04
# CentOS 5/6/7
# Scientific Linux Cern 5/6
#
# Packages you might want to install to use this command:
# debootstrap, rinse, xz-utils


# Define your local mirros here
# For the first stage, set the CentOS/SLC mirror in /etc/rinse/rinse.conf
MIRROR_DEBIAN=http://http.us.debian.org/debian
MIRROR_UBUNTU=http://mirror.netcologne.de/ubuntu/
MIRROR_TRISQUEL=http://mirror.fsf.org/trisquel/
MIRROR_CENTOS=http://mirror.netcologne.de/

EXCLUDE_SQUEEZE=isc-dhcp-client,isc-dhcp-common,info,tasksel,tasksel-data
EXCLUDE_WHEEZY=info,tasksel,tasksel-data
EXCLUDE_JESSIE=tasksel,tasksel-data
EXCLUDE_STRETCH=tasksel,tasksel-data
EXCLUDE_BELENOS=dhcp3-client,dhcp3-common,info
EXCLUDE_TRUSTY=dhcp3-client,dhcp3-common,info
EXCLUDE_XENIAL=tasksel,tasksel-data

INCLUDE_DEBIAN=aptitude


setarch() {

    l32=
    if [ X$1 = Xi386 ]; then
        l32=linux32
    fi
}

check() {

    if [ `id -u` != 0 ]; then
        echo "You must be root to create chroots."
        exit 1
    fi
    mknod $xtmp/test-dev-null c 1 3
    if [ $? -eq 1 ]; then
        echo "Cannot create device files on $xtmp, aborting."
        echo "Perhaps this directory is mounted with option nodev."
        rm -rf $xtmp
        exit 1
    fi
    echo test > $xtmp/test-dev-null
    if [ $? -eq 1 ]; then
        echo "Cannot create device files on $xtmp, aborting."
        echo "Perhaps this directory is mounted with option nodev."
        rm -rf $xtmp
        exit 1
    fi
    rm -f $xtmp/test-dev-null
}


mkpost-centos() {

    [ -z "$MIRROR_CENTOS" ] && return
    cat <<EOM > $xtmp/post
#! /bin/sh
mkdir -p $xtmp/etc/yum.repos.d/orig
cp -p $xtmp/etc/yum.repos.d/*.repo $xtmp/etc/yum.repos.d/orig
perl -pi -e 's,mirrorlist=,#mirrorlist=,; s,#baseurl=http://mirror.centos.org,baseurl=$MIRROR_CENTOS,;' $xtmp/etc/yum.repos.d/CentOS-Base.repo
EOM
    chmod 555 $xtmp/post
}


mkpost-slc() {

    ver=$1
    [ -z "$MIRROR_SLC" ] && return
    cat <<EOM > $xtmp/post
#! /bin/sh
mkdir -p $xtmp/etc/yum.repos.d/orig
cp -p $xtmp/etc/yum.repos.d/*.repo $xtmp/etc/yum.repos.d/orig
perl -pi -e 's,baseurl=http://linuxsoft.cern.ch,baseurl=$MIRROR_SLC,;' $xtmp/etc/yum.repos.d/slc$ver-os.repo
perl -pi -e 's,baseurl=http://linuxsoft.cern.ch,baseurl=$MIRROR_SLC,;' $xtmp/etc/yum.repos.d/slc$ver-updates.repo

EOM
    chmod 555 $xtmp/post
}


cleanup-deb() {

    chroot $xtmp aptitude clean
    rm -f $xtmp/etc/hostname $xtmp/etc/resolv.conf $xtmp/etc/machine-id
    rm $xtmp/var/lib/apt/lists/*_*
    rm -f $xtmp/etc/udev/rules.d/70-persistent-net.rules
}


cleanup-rinse() {

    # check if chroot works
    echo "Installed packages in chroot:"
    chroot $xtmp rpm -qa|sort
    echo -n "CHROOT rpm -qa: "
    chroot $xtmp rpm -qa|wc -l

    rm -f $xtmp/etc/resolv.conf $xtmp/post
    if [ -d $xtmp/etc/yum.repos.d/orig ]; then
        mv $xtmp/etc/yum.repos.d/orig/* $xtmp/etc/yum.repos.d/
        rm -rf $xtmp/etc/yum.repos.d/orig
    fi
}


tarit() {

    tar $attributes --one-file-system -C $xtmp -cf - . | $zip > $target.$ext
}


centos() {

    local arch=$1
    local vers=$2
    local domain=$(domainname)

    check
    setarch $arch
    mkpost-centos
    $l32 rinse --directory $xtmp --distribution centos-$vers --arch $arch --before-post-install $xtmp/post
    domainname $domain # workaround for #613377
    cleanup-rinse
    tarit
}


slc() {

    local arch=$1
    local vers=$2

    check
    setarch $arch
    mkpost-slc $vers
    $l32 rinse --directory $xtmp --distribution slc-$vers --arch $arch --before-post-install $xtmp/post
    cleanup-rinse
    tarit
}


debgeneric() {

    local DIST=$1
    shift
    local mirror=$1

    if [[ $DIST =~ 64 ]]; then
        arch=amd64
    else
        arch=i386
    fi

    DIST=${DIST%%??}
    dist=${DIST,,}

    local exc="EXCLUDE_$DIST"
    check
    debootstrap --arch $arch --exclude=${!exc} --include=${INCLUDE_DEBIAN} $dist $xtmp $mirror
    cleanup-deb
    tarit
}

prtdists() {

    echo "Available:

    CENTOS5_32   CENTOS5_64
    CENTOS6_32   CENTOS6_64
    CENTOS7_32   CENTOS7_64
    SLC5_32      SLC5_64
    SLC6_32      SLC6_64
                 SLC7_64
    TRUSTY32     TRUSTY64
    XENIAL32     XENIAL64
    SQUEEZE32    SQUEEZE64
    WHEEZY32     WHEEZY64
    JESSIE32     JESSIE64
    STRETCH32    STRETCH64
"
}

usage() {

    cat <<EOF
mk-basefile, create minimal base files for a Linux distritubtion

   Copyright (C) 2011-2016 by Thomas Lange

Usage: mk-basefile [OPTION] ... DISTRIBUTION

   -s                   Show list of supported linux distributions
   -a                   Add xtattrs, acl and selinux properties to the tar file.
   -d DIR               Use DIR for creating the temporary subtree structure.
   -z                   Use gzip for compressing the tar file.
   -J                   Use xz for compressing the tar file.
   -k                   Keep the temporary subtree structure, do not remove it.
   -h                   Print help.

 Usage example: mk-basefile -J STRETCH64
 This will create a STRETCH64.tar.xz basefile.

EOF
    exit 0
}

# main routine

ext=tar
zip=cat
attributes=
cleanup=1

while getopts ashzJd:k opt ; do
    case "$opt" in
        a) attributes="--xattrs --selinux --acl" ;;
        d) export TMPDIR=$OPTARG ;;
        z) zip="gzip -9"; ext=tar.gz ;;
        J) zip="xz -8" ext=tar.xz ;;
        k) cleanup=0 ;;
        h) usage ;;
        s) prtdists ; exit 0;;
        ?) exit 3 ;; # error in option parsing
    esac
done
shift $(($OPTIND - 1))

xtmp=$(mktemp --tmpdir -d basefiles.XXXXXXXX)
if [ $? -eq 1 ]; then
    echo "mktemp failed. Aborting."
    exit 2
fi

target=$1 # also the name of the output file

case "$target" in
    CENTOS5_32) centos i386 5 ;;
    CENTOS5_64) centos amd64 5 ;;
    CENTOS6_32) centos i386 6 ;;
    CENTOS6_64) centos amd64 6 ;;
    CENTOS7_32) centos i386 7 ;;
    CENTOS7_64) centos amd64 7 ;;
    SLC5_32) slc i386 5 ;;
    SLC5_64) slc amd64 5 ;;
    SLC6_32) slc i386 6 ;;
    SLC6_64) slc amd64 6 ;;
    SLC7_64) slc amd64 7 ;;
    BELANOS*)
        debgeneric $target $MIRROR_TRISQUEL ;;
    TRUSTY*|XENIAL*)
        debgeneric $target $MIRROR_UBUNTU ;;
    SQUEEZE*|WHEEZY*|JESSIE*|STRETCH*)
        debgeneric $target $MIRROR_DEBIAN ;;
    *) echo "Unknown distribution. Aborting."
       prtdists
       exit 99 ;;
esac

# cleanup
if [ $cleanup -eq 1 ]; then
   rm -rf $xtmp
fi