Fix licensing

CHANGELOG.md

@@ -1,3 +1,7 @@
+## [UNRELEASED] · YYYY-MM-DD
+### 🔧 Fixed
+- Fix `xdf.h`/`xdf.cpp` license headers that still said GPL-3.0 despite the project being BSD-2-Clause since 2020, and add `THIRD-PARTY-NOTICES.md` documenting the separate licenses of bundled smarc (LGPL-3.0) and pugixml (MIT) ([#65](https://github.com/xdf-modules/libxdf/pull/65) by [Clemens Brunner](https://github.com/cbrnr))
+
 ## [1.0.3] · 2026-07-14
 ### 🔧 Fixed
 - `libxdfConfig.cmake` no longer unconditionally requires system `pugixml` for library consumers ([#64](https://github.com/xdf-modules/libxdf/pull/64) by [Clemens Brunner](https://github.com/cbrnr))

CMakeLists.txt

@@ -84,6 +84,13 @@ install(
     COMPONENT ${PROJECT_NAME}
     DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/${PROJECT_NAME}
 )
+install(
+    FILES
+        ${CMAKE_CURRENT_LIST_DIR}/LICENSE
+        ${CMAKE_CURRENT_LIST_DIR}/THIRD-PARTY-NOTICES.md
+    COMPONENT ${PROJECT_NAME}
+    DESTINATION ${CMAKE_INSTALL_DATADIR}/doc/${PROJECT_NAME}
+)
 
 set(CPACK_PACKAGE_CONTACT "yida.lin@outlook.com")
 if(APPLE)

README.md

@@ -86,3 +86,8 @@ If you use libXDF in your project, please consider citing the following [confere
 > Yida Lin, Clemens Brunner, Paul Sajda and Josef Faller. *SigViewer: Visualizing Multimodal Signals Stored in XDF (Extensible Data Format) Files.* The 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.
 
 LibXDF depends on third party libraries [pugixml](http://pugixml.org/) for XML parsing and [Smarc](http://audio-smarc.sourceforge.net/) for resampling.
+
+
+## License
+
+LibXDF's own source code is licensed under the [BSD 2-Clause License](LICENSE). See [THIRD-PARTY-NOTICES.md](THIRD-PARTY-NOTICES.md) for details on the bundled third-party libraries.

THIRD-PARTY-NOTICES.md

@@ -0,0 +1,31 @@
+# Third-party notices
+
+libxdf's own source code is distributed under the BSD 2-Clause License (see
+[LICENSE](LICENSE)). It bundles two third-party libraries, each of which
+keeps its own original license — bundling them does not relicense them, and
+they are not covered by libxdf's own BSD 2-Clause terms.
+
+## smarc (`smarc/`)
+
+Copyright (c) 2009-2011 Institut Télécom - Télécom ParisTech, dept. TSI
+Authors: Benoit Mathieu, Jacques Prado
+
+Licensed under the **GNU Lesser General Public License, version 3 or later**
+(LGPL-3.0-or-later). See the header of any file under `smarc/` or
+<https://www.gnu.org/licenses/lgpl-3.0.html> for the full license text.
+
+smarc's `.c`/`.h` files are compiled directly into the `xdf` library target.
+Because libxdf is distributed as complete, buildable source (including the
+unmodified smarc sources), anyone receiving libxdf already has everything
+needed to modify smarc and relink it against the rest of the library, which
+satisfies the LGPLv3 §4 requirements for this kind of static combination.
+
+## pugixml (`pugixml/`)
+
+Copyright (c) 2006-2025 Arseny Kapoulkine
+
+Licensed under the **MIT License**. See the header of `pugixml/pugixml.hpp`
+or <https://opensource.org/license/mit> for the full license text.
+
+pugixml is used either as a system package (`find_package(pugixml)`) or, if
+unavailable, built from the bundled copy in `pugixml/`.

xdf.cpp

@@ -1,19 +1,7 @@
 //libxdf is a static C++ library to load XDF files
-//Copyright (C) 2017  Yida Lin
-
-//This program 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 3 of the License, or
-//(at your option) any later version.
-
-//This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
-//If you have questions, contact author at yida.lin@outlook.com
+//Copyright (c) 2017-2020, Yida Lin, Clemens Brunner, Paul Sajda, Josef Faller
+//
+//Distributed under the BSD 2-Clause License. See LICENSE for details.
 
 
 #include "xdf.h"

xdf.h

@@ -1,19 +1,7 @@
 //libxdf is a static C++ library to load XDF files
-//Copyright (C) 2017  Yida Lin
-
-//This program 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 3 of the License, or
-//(at your option) any later version.
-
-//This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
-//If you have questions, contact author at yida.lin@outlook.com
+//Copyright (c) 2017-2020, Yida Lin, Clemens Brunner, Paul Sajda, Josef Faller
+//
+//Distributed under the BSD 2-Clause License. See LICENSE for details.
 
 /*! \file xdf.h
  * \brief The header file of Xdf class