FNV hash for strings

fnv.cpp

uint64_t fnvhash(const char* data, size_t size) {
    uint64_t hsh = 14695981039346656037L;
    for (size_t i = 0; i < size; ++i) {
        hsh = (hsh * 1099511628211L) ^ (uint64_t)(data[i]);
    }
    return hsh;
}

// Calculating the hash for QString
template <>
struct hash<QString> {
    size_t operator() (const QString& s) {
        return fnvhash(s.data(), s.size());
    }
};