/usr/include/ql/pricingengines/swap/ is in libquantlib0-dev 1.12-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/ql/pricingengines/swap/all.hpp
/usr/include/ql/pricingengines/swap/cvaswapengine.hpp
/usr/include/ql/pricingengines/swap/discountingswapengine.hpp
/usr/include/ql/pricingengines/swap/discretizedswap.hpp
/usr/include/ql/pricingengines/swap/treeswapengine.hpp
/usr/include/ql/pricingengines/swaption/all.hpp
/usr/include/ql/pricingengines/swaption/basketgeneratingengine.hpp
/usr/include/ql/pricingengines/swaption/blackswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/discretizedswaption.hpp
/usr/include/ql/pricingengines/swaption/fdg2swaptionengine.hpp
/usr/include/ql/pricingengines/swaption/fdhullwhiteswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/g2swaptionengine.hpp
/usr/include/ql/pricingengines/swaption/gaussian1dfloatfloatswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/gaussian1djamshidianswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/gaussian1dnonstandardswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/gaussian1dswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/jamshidianswaptionengine.hpp
/usr/include/ql/pricingengines/swaption/treeswaptionengine.hpp