Xerces-C++ is a validating XML parser written in a portable subset of C++.
Xerces-C++ makes it easy to give your application the ability to read and
write XML data. A shared library is provided for parsing, generating,
manipulating, and validating XML documents. 
Xerces-C++ is faithful to the XML 1.0 recommendation and many associated
standards (see Features below). 
The parser provides high performance, modularity, and scalability. Source
code, samples and API documentation are provided with the parser. For
portability, care has been taken to make minimal use of templates, no RTTI,
and minimal use of #ifdefs.

Xerces is licensed under the ASL (Apache Software License) version 2.0 which
you can find a copy of in ASL-2.0-License.txt or at
http://www.apache.org/licenses/LICENSE-2.0.html