Here are the data structures with brief descriptions:

CXXH128_canonical_t
CXXH128_hash_t	The return value from 128-bit hashes
CXXH32_canonical_t	Canonical (big endian) representation of XXH32_hash_t
CXXH32_state_s
CXXH3_state_s
CXXH64_canonical_t	Canonical (big endian) representation of XXH64_hash_t
CXXH64_state_s