Function xo_anchor_stop

tools/libxo/libxo/libxo.c:5249–5311

}

static void
xo_anchor_stop (xo_handle_t *xop, xo_field_info_t *xfip,
		 const char *value, ssize_t vlen)
{
    if (!XOIF_ISSET(xop, XOIF_ANCHOR)) {
	xo_failure(xop, "no start anchor");
	return;
    }

    XOIF_CLEAR(xop, XOIF_UNITS_PENDING);

    ssize_t width = xo_find_width(xop, xfip, value, vlen);
    if (width == 0)
	width = xop->xo_anchor_min_width;

    if (width == 0)		/* No width given; nothing to do */
	goto done;

    xo_buffer_t *xbp = &xop->xo_data;
    ssize_t start = xop->xo_anchor_offset;
    ssize_t stop = xbp->xb_curp - xbp->xb_bufp;
    ssize_t abswidth = (width > 0) ? width : -width;
    ssize_t blen = abswidth - xop->xo_anchor_columns;

    if (blen <= 0)		/* Already over width */
	goto done;

    if (abswidth > XO_MAX_ANCHOR_WIDTH) {
	xo_failure(xop, "width over %u are not supported",
		   XO_MAX_ANCHOR_WIDTH);
	goto done;
    }

    /* Make a suitable padding field and emit it */
    char *buf = alloca(blen);
    memset(buf, ' ', blen);
    xo_format_content(xop, "padding", NULL, buf, blen, NULL, 0, 0);

    if (width < 0)		/* Already left justified */
	goto done;

    ssize_t now = xbp->xb_curp - xbp->xb_bufp;
    ssize_t delta = now - stop;
    if (delta <= 0)		/* Strange; no output to move */
	goto done;

    /*
     * Now we're in it alright.  We've need to insert the padding data
     * we just created (which might be an HTML <div> or text) before
     * the formatted data.  We make a local copy, move it and then
     * insert our copy.  We know there's room in the buffer, since
     * we're just moving this around.
     */
    if (delta > blen)
	buf = alloca(delta);	/* Expand buffer if needed */

    memcpy(buf, xbp->xb_bufp + stop, delta);
    memmove(xbp->xb_bufp + start + delta, xbp->xb_bufp + start, stop - start);