Function xo_buf_append_locale_from_utf8

tools/libxo/libxo/libxo.c:1174–1215

* Append a single UTF-8 character to a buffer, converting it to locale * encoding. Returns the number of columns consumed by that character, * as best we can determine it. */

 * as best we can determine it.
 */
static ssize_t
xo_buf_append_locale_from_utf8 (xo_handle_t *xop, xo_buffer_t *xbp,
				const char *ibuf, ssize_t ilen)
{
    wchar_t wc;
    ssize_t len;

    /*
     * Build our wide character from the input buffer; the number of
     * bits we pull off the first character is dependent on the length,
     * but we put 6 bits off all other bytes.
     */
    wc = xo_utf8_char(ibuf, ilen);
    if (wc == (wchar_t) -1) {
	xo_failure(xop, "invalid UTF-8 byte sequence");
	return 0;
    }

    if (XOF_ISSET(xop, XOF_NO_LOCALE)) {
	if (!xo_buf_has_room(xbp, ilen))
	    return 0;

	memcpy(xbp->xb_curp, ibuf, ilen);
	xbp->xb_curp += ilen;

    } else {
	if (!xo_buf_has_room(xbp, MB_LEN_MAX + 1))
	    return 0;

	bzero(&xop->xo_mbstate, sizeof(xop->xo_mbstate));
	len = wcrtomb(xbp->xb_curp, wc, &xop->xo_mbstate);

	if (len <= 0) {
	    xo_failure(xop, "could not convert wide char: %lx",
		       (unsigned long) wc);
	    return 0;
	}
	xbp->xb_curp += len;
    }

    return xo_wcwidth(wc);
}

/*
 * Append a UTF-8 string to a buffer, converting it into locale encoding