Light C Unicode Library

Question

I'm looking for a small C library to handle utf8 strings.

Specifically, splitting based on unicode delimiters for use with stemming algorithms.

Related posts have suggested:

ICU http://www.icu-project.org/ (I found it too bulky for my purposes on embedded devices)

UTF8-CPP: http://utfcpp.sourceforge.net/ (Excellent, but C++ not C)

Has anyone found any platform independent, small codebase libraries for handling unicode strings (doesn't need to do naturalisation).

Solution 1

A nice, light, library which I use successfully is utf8proc.

Solution 2

There's also MicroUTF-8, but it may require login credentials to view or download the source.

Solution 3

UTF-8 is specially designed so that many byte-oriented string functions continue to work or only need minor modifications.

C's strstr function, for instance, will work perfectly as long as both its inputs are valid, null-terminated UTF-8 strings. strcpy works fine as long as its input string starts at a character boundary (for instance the return value of strstr).

So you may not even need a separate library!

Comments

[barney]

utf8-cpp is great! ported smoothly to ios/android. header only libarary

[cutiko]

Very True, until now I had only needed to store/copy strings and was doing just that. But then I started needing to split/stem words for indexing so I wanted to make sure I was dealing with them properly.

[Ethan]

While they work, searching functions will probably not perform as well in the face of UTF-8 characters. For example, if a UTF-8 character can be determined to not match immediately (often possible if it's compared with an ASCII character), the entire UTF-8 character encoding, which can be multiple bytes, can be skipped. But you're right that some of C's functions will work fine with UTF-8 strings, which is one of the reasons that UTF-8 is popular.

[Adrian Maire]

Not crashing is not the same than working: something as simple as the string size does not work for UTF-8. UTF-8 is NOT designed especially for library compatibility.