#!/usr/bin/perl -w
#
# The LearningOnline Network
#
# excise_from_db.pl - Remove a key from a db file.
#
# $Id: excise_from_db.pl,v 1.1 2004/01/27 18:42:25 matthew Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA 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.
#
# LON-CAPA 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 LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
#################################################
use strict;
use GDBM_File;

#
# Options
my $fname = shift;
my $key = shift;

my %db;
if (! tie(%db,'GDBM_File',$fname,&GDBM_WRITER,0640)) {
    warn "Unable to tie to $fname";
    next;
}
delete($db{$key});
delete($db{&escape($key)});

untie %db;

exit;

######################################
sub escape {
    my $str=shift;
    $str =~ s/(\W)/"%".unpack('H2',$1)/eg;
    return $str;
}

sub unescape {
    my $str=shift;
    $str =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
    return $str;
}