textproc/uni-algo 1.2.0 DragonFly

There are plenty of Unicode libraries for C/C++ out there that implement random Unicode algorithms, but many of them don't handle ill-formed UTF sequences at all. In the best-case scenario, you'll get an exception/error; in the worst-case, undefined behavior. The biggest problem is that in 99%25 cases everything will be fine. This is inappropriate for security reasons. This library handles such problems (there are not only ill-formed sequences actually) properly and always according to The Unicode Standard.

In C/C++, unlike some other programming languages, there is no safe type for UTF-8/UTF-16 that guarantees that the data will be well-formed; this makes the problem even worse. The library doesn't introduce such a type either because the library doesn't work with types/strings/files/streams, it works with the data inside them and makes it safe when it's needed.

Check this article if you want more information about ill-formed sequences: https://hsivonen.fi/broken-utf-8

It is a bit outdated because ICU (International Components for Unicode) now uses W3C conformant implementation too, but the information in the article is very useful.

This library does use W3C conformant implementation too.