#!/bin/sh -e
# $URL: svn+ssh://svn.debian.org/svn/svn/pkg-mailman/trunk/debian/preinst.in $
# $Id: preinst.in 641 2009-12-30 16:02:13Z thijs $

. /usr/share/debconf/confmodule



abort_install()
{
    db_fset mailman/queue_files_present seen false || true
    db_input critical mailman/queue_files_present || true
    db_go
    db_get mailman/queue_files_present
    if [ "$RET" = "abort installation" ]; then
        exit 1
    fi
}

# make sure the qfiles directory is empty.
if [ -d /var/lib/mailman/qfiles ] && \
	[ "$(find /var/lib/mailman/qfiles -type f | wc -l)" -ne 0 ]; then
    # Check if the queue files were created by the same version as the one we're about to install
    if [ -r /var/lib/mailman/.version ]; then
	# First check the stamp file.
	# It is more general because it will show the previous version in the
	# case that /var/lib/mailman is on permanent storage (e.g. a SAN) and
	# we are being installed for the first time.
        previous_version=$(cat /var/lib/mailman/.version)
    else
        # Fall back to reading dpkg-provided argument (in case previous version did not leave the stamp file)
        previous_version="$2"
    fi
    if [ "1:2.1.13-1ubuntu0.2" != "${previous_version}" ]; then
        # we don't know which version the files are from
        abort_install
    fi
fi

exit 0