Complete REUSE support

[urcu.git] / LICENSE.md

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+# Userspace RCU library licensing
+
+This project is compliant with the [REUSE](https://reuse.software/spec/)
+specification, each file contains [SPDX](https://spdx.org/specifications) tags,
+the full licenses can be found in the `LICENSES/` directory.
+
+
+## Library code
+
+The library part is distributed under `LGPL-2.1-or-later`. See
+`LICENSES/LGPL-2.1-or-later.txt` for license details. Refer to the individual
+file headers for details.
+
+LGPL-compatible source code can statically use the library header using :
+
+````
+#define _LGPL_SOURCE
+#include <urcu.h>
+````
+
+Dynamic-only linking with the LGPL library is used if `_LGPL_SOURCE` is not
+defined. It permits relinking with newer versions of the library, which is
+required by the LGPL license.
+
+See `lgpl-relicensing.md` for details.
+
+
+## Headers
+
+Most headers are also distributed under `LGPL-2.1-or-later`, some include code
+from `atomic_ops` and are distributed under `Boehm-GC` and some others are
+distributed under `MIT`. Refer to the individual file headers for details.
+
+xchg() primitive has been rewritten from scratch starting from `atomic_ops 1.2`
+which has a MIT-style license that is intended to allow use in both free and
+proprietary software:
+
+````
+http://www.hpl.hp.com/research/linux/atomic_ops/LICENSING.txt
+http://www.hpl.hp.com/personal/Hans_Boehm/gc/gc_source/
+````
+
+
+## Tests
+
+Library test code is distributed under the `GPL-2.0-only` license. See
+`LICENSES/GPL-2.0-only.txt` for license details. See headers of individual
+files under `tests/` for details.
+
+
+## Documentation
+
+The documentation is distributed under the `CC-BY-4.0` license.
+
+
+## Build system
+
+Build system related files are mostly distributed under the `MIT` license. See
+headers of individual files for details.
+
+
+## Generated data files
+
+Generated data files are distributed under the `CC-1.0` license.