Clarify License (pugXML reference)

[bilbothebaggins]

pugixml.hpp declares:

 * Copyright (C) 2006-2025, by Arseny Kapoulkine ([email protected])
 * ...
 * This library is distributed under the MIT License. (...)
 *
! * This work is based on the pugxml parser, which is:
! * Copyright (C) 2003, by Kristen Wegner ([email protected])

This came up during license review:
You declare work is based on the pugxml parser ... * Copyright (C) 2003, by Kristen Wegner

However, tracing that base license is difficult and it is not explicitly spelled out.

The codeproject page seems dead, here's a wayback link, but that doesn't declare a license and the source code is not available.

I only found: https://github.com/tsaikd/MagicKD/blob/master/trunk/FuncBase/pugxml.h which declares:

// Pug XML Parser - Version 1.0002
// --------------------------------------------------------
// Copyright (C) 2003, by Kristen Wegner ([email protected])
// Released into the Public Domain. Use at your own risk.
// See pugxml.xml for further information, history, etc.
// Contributions by Neville Franks ([email protected]).

So it would appear that the original code was actually released into the public domain (under US law, by a private person, given the description that is available on the old codeproject page).
That would seem to indeed cover redistributing any used code under MIT (or anything else).

To ease pressure on us poor folks having to argue licensing details, would you accept a pull request that cleans that up?

Also, do you still have the original pugxml sources, including pugxml.xml ? Would you consider uploading them for reference, as codeproject seems broken?

Thanks.

[zeux]

I don't have the original pugxml sources unfortunately. But yeah I believe it was public domain; worth noting also is that pugixml is very very different from pugxml at this point, there's some similarities in the core parser as it evolved from pugxml as a base but as you can guess it changed dramatically over 20 years even if pugxml was the starting point :)

I'd be happy to accept a PR that clarifies the pugxml licensing terms but please keep the extra text minimal; we'd also need to make sure it's clear that while pugxml was public domain, pugixml itself is under MIT license.

[bilbothebaggins]

Thanks.
I'll try to come up with something, and yes, minimal would also be my goal here.