Re: grep: fix multibyte regex handling under macOS (1819ad327b7a1f19540a819813b70a0e8a7f798f)

From: D. Ben Knoble <ben.knoble@gmail.com>
Date: Feb 3, 2023, 17:06 UTC
Message-ID: <CALnO6CAfKA2atXwHXGJxnBGJ46EMbjGmFU54mb4FJL2O8ceXyQ@mail.gmail.com>
In-Reply-To: <Y908f2qaxKeljtj+@coredump.intra.peff.net>

On Fri, Feb 3, 2023 at 11:55 AM Jeff King <peff@peff.net> wrote:

Show 6 quoted lines

> Just a guess, but does calling:
>
>   setlocale(LC_CTYPE, "");
>
> at the start of the program change things (you'll probably need to also
> include locale.h)?

Indeed, the new output is

    illegal byte sequence

For the following program

    #include <regex.h>
    #include <assert.h>
    #include <stddef.h>
    #include <stdio.h>
    #include <locale.h>

    int main(int argc, char **argv) {
        char *loc = setlocale(LC_CTYPE, "");
        assert (loc != NULL);
        regex_t re;
        int ret = regcomp(&re, "[\xc0-\xff][\x80-\xbf]+", REG_EXTENDED
| REG_NEWLINE);
        /* assert(ret != 0); */
        size_t errbuf_size = regerror(ret, &re, NULL, 0);
        char errbuf[errbuf_size];
        regerror(ret, &re, errbuf, errbuf_size);
        printf("%s\n", errbuf);
    }

My own locale output, for completion's sake:

    LANG="fr_FR.UTF-8"
    LC_COLLATE="fr_FR.UTF-8"
    LC_CTYPE="fr_FR.UTF-8"
    LC_MESSAGES="fr_FR.UTF-8"
    LC_MONETARY="fr_FR.UTF-8"
    LC_NUMERIC="fr_FR.UTF-8"
    LC_TIME="fr_FR.UTF-8"
    LC_ALL="fr_FR.UTF-8"

-- 
D. Ben Knoble