Where does glibc get its database of unicode attributes? [closed]

Question

Where does glibc get its database of unicode attributes, for such functions as eg, wcwidth()? I'm interested in correcting a few errant entries, but I can't seem to find where this information is in its source distribution.

If it matters, I'm primarily interested in this under debian or ubuntu linux.

Answer 1

Okay, so I'm just poking around myself so I'm not absolutely sure, but it appears that the table you are looking for is found in the following location relative to the glibc root:

localedata/locales/i18n

This appears to be the Unicode (version 5) locale. It contains the following, which is where I believe you need to make your changes:

% ENCLOSED ALPHANUMERICS/
   <U24D0>..<U24E9>;/

In case you're wondering, the function ctype_output (ld-ctype.c) calls allocate_arrays which calls wcwidth_table_init. The function wcwidth_table_init is generated by 3level.h (which also generates other tables that follow the same template). This is the chain that I followed to track down the files in localedate/locales.

Like I said, I'm not 100% sure that this is the right table, but I thought I'd share what I had found.

Answer 2

It looks like the data is generated by the (apparently manually-run) localedata/gen-unicode-ctype.c from the unicode datafiles published at http://unicode.org/Public/UNIDATA/ . Thanks to Naaff for pointing me in the right direction!

Answer 3

I believe that it's defined in the locale definition file. See this page for more information about locales. glibc includes a bunch of locale definitions in localedate/locales, although none of them seem to have any width information.