Function xo_count_utf8_cols

tools/libxo/libxo/libxo.c:3059–3093

}

static ssize_t
xo_count_utf8_cols (const char *str, ssize_t len)
{
    ssize_t tlen;
    wchar_t wc;
    ssize_t cols = 0;
    const char *ep = str + len;

    while (str < ep) {
	tlen = xo_utf8_to_wc_len(str);
	if (tlen < 0)		/* Broken input is very bad */
	    return cols;

	wc = xo_utf8_char(str, tlen);
	if (wc == (wchar_t) -1)
	    return cols;

	/* We only print printable characters */
	if (iswprint((wint_t) wc)) {
	    /*
	     * Find the width-in-columns of this character, which must be done
	     * in wide characters, since we lack a mbswidth() function.
	     */
	    ssize_t width = xo_wcwidth(wc);
	    if (width < 0)
		width = iswcntrl(wc) ? 0 : 1;

	    cols += width;
	}

	str += tlen;
    }

    return cols;
}

#ifdef HAVE_GETTEXT
static inline const char *