#! /bin/sh -e
###
### Construct a fresh build-chroot base
###
### (c) 2018 Mark Wooding
###

###----- Licensing notice ---------------------------------------------------
###
### This file is part of the distorted.org.uk chroot maintenance tools.
###
### distorted-chroot is free software: you can redistribute it and/or
### modify it under the terms of the GNU General Public License as
### published by the Free Software Foundation; either version 2 of the
### License, or (at your option) any later version.
###
### distorted-chroot is distributed in the hope that it will be useful,
### but WITHOUT ANY WARRANTY; without even the implied warranty of
### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
### General Public License for more details.
###
### You should have received a copy of the GNU General Public License
### along with distorted-chroot.  If not, write to the Free Software
### Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
### USA.

. state/config.sh # @@@config@@@

## Convert the PROXY configuration setting into something that will affect
## `debootstrap'.
case $PROXY in nil) ;; *) http_proxy=$PROXY; export PROXY ;; esac

## Parse the command-line.
badp=nil forcep=nil
while getopts "f" opt; do
  case $opt in
    f) forcep=t ;;
    *) badp=t ;;
  esac
done
shift $(( $OPTIND - 1 ))
case $# in 2) ;; *) badp=t ;; esac
case $badp in t) echo >&2 "usage: $0 [-f] DIST ARCH"; exit 2 ;; esac
d=$1 a=$2

case $d-$a in *-*-*) echo >&2 "$0: bad chroot name \`$arg'"; exit 2 ;; esac
if [ ! -d /dev/$VG/ ]; then echo >&2 "$0: no volume group \`$VG'"; exit 2; fi

## Decide whether we need to do special things for installing a foreign
## architecture.
qemup=nil dbsopts=
for fa in $FOREIGN_ARCHS; do
  case $fa in
    "$a")
      qemup=t dbsopts=--foreign
      eval qarch=\$${a}_QEMUARCH qhost=\$${a}_QEMUHOST
      break
      ;;
  esac
done

## Construct the logical volume and lay a filesystem onto it.
lv=$LVPREFIX$d-$a
mnt=$HERE/mnt/$lv
mkdir -p $mnt
if mountpoint -q $mnt; then umount $mnt; fi
if [ -b /dev/$VG/$lv ]; then
  case $forcep in
    nil) echo >&2 "$0: volume \`$lv' already exists"; exit 2 ;;
    t) lvremove -f $VG/$lv ;;
  esac
fi
lvcreate --yes $LVSZ -n$lv $VG
mkfs -j -L$d-$a /dev/$VG/$lv
mount -orelatime,data=writeback,commit=3600,barrier=0 /dev/$VG/$lv $mnt/
mkdir -m755 $mnt/fs/
chmod 750 $mnt/

## Install the base system.
want=$BASE_PACKAGES
case $qemup in
  t) want="$want $FOREIGN_BASE_PACKAGES" ;;
  nil) want="$want $NATIVE_BASE_PACKAGES" ;;
esac
pkgs=; for p in $want; do pkgs=${pkgs:+$pkgs,}$p; done
eatmydata debootstrap $dbsopts --arch=$a --variant=minbase \
	  --include=$pkgs $d $mnt/fs/ $DEBMIRROR

## If this is a cross-installation, then install the necessary `qemu' and
## complete the installation.
case $qemup in
  t)
    install $LOCAL/cross/$d-$qhost/QEMU/qemu-$qarch-static \
	    $mnt/fs/usr/bin/
    chroot $mnt/fs/ /debootstrap/debootstrap --second-stage
    ln -sf /usr/local.schroot/cross/$d-$qhost/QEMU/qemu-$qarch-static \
       $mnt/fs/usr/bin/
    ;;
esac

## Set up `/usr/local'.
rm -rf $mnt/fs/usr/local/; ln -s local.schroot/$a $mnt/fs/usr/local

## Install the `apt' configuration.
rm -rf $mnt/fs/etc/apt/apt.conf $mnt/fs/etc/apt/sources.list
for c in $LOCAL/etc/apt/apt.conf.d/*; do
  ln -s /usr/local.schroot/${c#$LOCAL/} $mnt/fs/etc/apt/apt.conf.d/
done
ln -s /usr/local.schroot/etc/apt/sources.$d $mnt/fs/etc/apt/sources.list

cat >$mnt/fs/etc/apt/apt.conf.d/20arch <<EOF
### -*-conf-*-

APT {
	Architecture "$a";
};
EOF

## Set up the locale and time zone from the host system.
cp /etc/locale.gen /etc/timezone $mnt/fs/etc/
tz=$(cat /etc/timezone); ln -sf /usr/share/zoneinfo/$tz $mnt/fs/etc/localtime
ln -sf /proc/mounts $mnt/fs/etc/mtab

cp /etc/default/locale $mnt/fs/etc/default/

## Prevent daemons from starting within the chroot.
cat >$mnt/fs/usr/sbin/policy-rc.d <<EOF
#! /bin/sh
echo >&2 "policy-rc.d: Services disabled by policy."
exit 101
EOF
chmod +x $mnt/fs/usr/sbin/policy-rc.d

## Hack the dynamic linker to prefer libraries in `/usr' over `/usr/local'.
cat >$mnt/fs/etc/ld.so.conf.d/libc.conf <<EOF
# libc default configuration
EOF
cat >$mnt/fs/etc/ld.so.conf.d/zzz-local.conf <<EOF
### -*-conf-*-
### Local hack to make /usr/local/ late.
/usr/local/lib
EOF

## We're done setting the chroot environment up.
umount $mnt/

## If this is a foreign architecture then we need to set it up.
case $qemup in
  t)
    ## Keep the chroot's native Qemu out of our way: otherwise we'll stop
    ## being able to run programs in the chroot.  There's a hack here because
    ## the `--no-rename' option was required in the same version in which is
    ## was introduced, so there's no single incantation that will work across
    ## the boundary.
    schroot -uroot -csource:$LVPREFIX$d-$a -- eatmydata sh -e -c "
	if dpkg-divert >/dev/null 2>&1 --no-rename --help
	then no_rename=--no-rename
	else no_rename=
	fi

	dpkg-divert --package install-cross-tools \$no_rename \
	  --divert /usr/bin/qemu-$qarch-static.$a --add /usr/bin/qemu-$qarch-static"

    ## Install faster native tools.
    $STATE/bin/install-cross-tools $d $a

    ## Install `build-essential', which had been delayed from earlier.
    schroot -uroot -csource:$LVPREFIX$d-$a -- \
	    eatmydata apt-get -y install build-essential
    ;;
esac

## Set the chroot's package state up properly.
schroot -uroot -csource:$LVPREFIX$d-$a -- eatmydata sh -e -c '
	apt-get update
	apt-get -y upgrade
	locale-gen
	ldconfig
	apt-get -y autoremove
	apt-get clean'

###----- That's all, folks --------------------------------------------------