#!/bin/sh
# See deb-postinst(5).

set -e

PROGNAME=dpkg

. /usr/share/dpkg/sh/dpkg-error.sh

setup_colors

get_vendor()
{
  local origin="$DPKG_ROOT/etc/dpkg/origins/default"
  local vendor

  if [ -e "$origin" ]; then
    vendor=$(sed -ne 's/^Vendor: *\([^ ]\+\) */\1/p' "$origin" | tr A-Z a-z)
  fi

  echo "${vendor:-default}"
}

check_merged_usr_via_aliased_dirs()
{
  local vendor

  vendor=$(get_vendor)

  case "$vendor" in
  debian)
    # In Debian some people have gotten so offended by the following _warning_
    # that they have resorted to bullying and abuse. Life's too short, sorry.
    return
    ;;
  ubuntu)
    # Ubuntu does not seem interested in it.
    return
    ;;
  esac

  for d in /bin /sbin /lib /lib32 /libo32 /libx32 /lib64; do
    linkname="$(readlink $DPKG_ROOT$d || true)"
    if [ "$linkname" = "usr$d" ] || [ "$linkname" = "/usr$d" ]; then
      warning "This system uses merged-usr-via-aliased-dirs, going behind dpkg's"
      warning "back, breaking its core assumptions. This can cause silent file"
      warning "overwrites and disappearances, and its general tools misbehavior."
      warning "See <https://wiki.debian.org/Teams/Dpkg/FAQ#broken-usrmerge>."
      break
    fi
  done
}

# Version 1.21.0 had bogus handling of DPKG_ADMINDIR in update-alternatives,
# and misplaced them, fix them up.
fixup_misplaced_alternatives()
(
  admindir=${DPKG_ADMINDIR:-/var/lib/dpkg}

  cd "$admindir"

  for file in *; do
    if ! [ -f "$file" ]; then
      # Ignore anything that is not a file.
      continue
    fi

    # Check whether this is a known file we do not want to act on.
    case "$file" in
    arch|\
    available|available-old|\
    cmethopt|methlock|\
    diversions|diversions-old|\
    lock|lock-frontend|\
    statoverride|statoverride-old|\
    status|status-old)
      # Ignore known files just to make sure.
      continue
      ;;
    *)
    esac

    # Check whether the file looks like an alternative state file.
    mode="$(head -1 "$file")"
    case "$mode" in
    auto|manual)
      # Looks like a state file, we will handle this one.
      echo "Moving misplaced alternative state file $admindir/$file..."
      mv "$file" "alternatives/$file"
      ;;
    *)
      warning "unknown dpkg database file $admindir/$file is not a misplaced alternative state... leaving as is"
      continue
      ;;
    esac
  done
)

case "$1" in
configure)
  fixup_misplaced_alternatives
  ;;
abort-upgrade|abort-deconfigure|abort-remove)
  ;;
*)
  error "called with unknown argument '$1'"
  ;;
esac

#DEBHELPER#
exit 0