LICENSE.txt

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
    or get them via Internet at:

    * v2.0: http://www.gnu.org/licenses/lgpl-2.0.txt
    * v2.1: http://www.gnu.org/licenses/lgpl-2.1.txt
    * v3.0: http://www.gnu.org/licenses/lgpl-3.0.txt