https://github.com/open62541/open62541

License: MPL 2.0, (like LGPL with static linking exception).
To update (from an open62541 checkout):

cmake -D UA_ENABLE_SUBSCRIPTIONS=ON -D UA_ENABLE_AMALGAMATION=ON .
make -j2
cp open62541.{c,h} /path/to/3rdParty/open62541/
git diff -U0 -w --no-color | git apply --cached --ignore-whitespace --unidiff-zero -
git commit
git reset --hard

We only include the single c/h-file in order to not include
documentation, etc.
