knight666

This is actually guarded against in a macro:

    #define UTF8_VALIDATE_PARAMETERS(_inputType, _outputType, _result) \
        if (input == 0) { \
            UTF8_SET_ERROR(INVALID_DATA); \
            return _result; \
        } \

However, you are correct about codepoint_read's behavior. I actually have a test for passing NUL to the function, but the value of decoded isn't checked:

    TEST(CodepointRead, InvalidData)
    {
        const char* i = nullptr;
        size_t il = 0;
        unicode_t o;

        EXPECT_EQ(0, codepoint_read(i, il, &o));
    }

Nevertheless, I thank you for the extra set of eyeballs. I have been looking at these functions far too long, you tend to gloss over obvious problems after a while.

I'll be sure to get a fix in for the next release. :)

You can find all case folding codepoints on the Unicode Consortium website: ftp://ftp.unicode.org/Public/UNIDATA/CaseFolding.txt and ftp://ftp.unicode.org/Public/UNIDATA/SpecialCasing.txt.

As you get down the list you'll notice what a pain in the ass the special cases are. There's a special case for the final sigma in a Greek word:

    03A3; 03C2; 03A3; 03A3; Final_Sigma; # GREEK CAPITAL LETTER SIGMA

    0307; 0307; ; ; lt After_Soft_Dotted; # COMBINING DOT ABOVE

Unicode case mapping is just a huge mess of exceptions, but that's more the humans' fault than the standard.

It wasn't before, but I looked up how to host static HTML on Bitbucket. You can now read the documentation online here:

http://knight666.bitbucket.org/utf8rewind/

No, currently Turkish, Greek, Lithuanian and Azeri case mappings are not always grammatically correct. This is because utf8rewind currently does not take the system locale into account when case mapping. Fixing these issues is planned for a future release.

Author here.

The library currently doesn't employ any kind of fuzzing. I rely on multiple tests for every kind of input. I've found that is a pretty reliable way to test for "unknown unknowns", even if it's extremely time-consuming.

Adding testcase fuzzing is definitely something to consider though, because it would most likely have found the very issues this release fixes.

You've probably never heard of it because it has 136 downloads in total. ;)

It's very thoroughly tested but it hasn't been used in any serious projects yet.