## tidy loose ends
set -e;
# fix mark auto-installed essential packages + dependencies (bug#742977)
 _pkgdeps(){ set -e;
  chroot /target dpkg-query
    -Wf=',${Pre-Depends},${Depends},${Recommends}\n' $* 2>/dev/null
    | sed -r
    -e 's/[,|] *([a-z0-9.+-]+)?(:\s+)?( *[^|,]*)?/\1\n/g'
    | sed '/^$/d'|sort -u; };
 _pkg2re(){ set -e;
  echo $*
    | sed -r
    -e 's/\s+/\|/g;'
    -e 's/^\|//;'
    -e 's/([.+-])/\\\1/g;'
    -e 's/\|$//'; };
 _pkgreal(){ set -e;
  chroot /target dpkg-query
    -Wf='${Package},${Provides},\n'
    | sed -r
    -e '/,,/d;'
    -e 's/^([a-z0-9.+-]+).*[,|] *('"$(_pkg2re $*)"')[ :,]/\1/;'
    -e '/,/d'; };
 _pkganddeepdeps(){ set -e;
  rest=$*;
  all=$rest;
  for i in 1 2 3 4 5; do
    deps=$(_pkgdeps $rest);
    rest="$deps $(_pkgreal $deps)";
    all="$all $rest";
  done;
  echo $all
    | sed -r
    -e 's/\s+/\n/g'
    | sort -u; };
 _pkgessentials(){ set -e;
  chroot /target dpkg-query
    -Wf='${Package}%${Essential}\n'
    | sed -r
    -e 's/(.*)%yes/\1/;'
    -e '/%/d'; };
 chroot /target apt-mark auto
  $(_pkganddeepdeps $(_pkgessentials) apt linux-image-*);
# fix mark auto-installed misc. packages relevant only as dependencies
 chroot /target apt-mark auto
  apt-utils aptitude-common grub-common isc-dhcp-common tasksel-data vim-common;

# keep backup of any tweaked (i.e. edited or created) config file
 _backup(){ set -e;
  if [ -e "$1.orig" ]; then
    :;
  elif [ -e "$1" ]; then
    cp -a "$1" "$1.orig";
  else
    touch "$1.orig";
  fi; };
 _clone(){ set -e;
  _backup "$2";
  cp -a "$1" "$2"; };
 _setvar(){ set -e;
  _backup "$1";
  sed -i -r
    -e "s,^#?($2)=.*,\\1=$3," "$1"; };

## improve autonomy
# auto-repair inconsistent filesystems during boot
 _setvar /target/etc/default/rcS FSCKFIX yes;