Function mangle_tty_rows_columns

outdated/sys/mac/mactty.c:1126–1171

* Delete or insert operations used by many terminals can bottleneck through * here. Note that the order of executin for row/colum insertions is NOT * specified. Negative values for num_ mean delete, zero means no effect. */

 * specified. Negative values for num_ mean delete, zero means no effect.
 */
short
mangle_tty_rows_columns(WindowPtr window, short from_row, short num_rows,
                        short from_column, short num_columns)
{
    Rect r;
    RgnHandle rh = NewRgn();
    RECORD_EXISTS(record);

    update_tty(window); /* Always make sure screen is OK */
    curs_pos(record, record->x_curs, record->y_curs, 0);

    if (num_rows) {
        pos_rect(record, &r, 0, from_row, record->x_size - 1,
                 record->y_size - 1);
        select_offscreen_port(record);
        ScrollRect(&r, 0, num_rows * record->row_height, rh);
        EraseRgn(rh);
        SetEmptyRgn(rh);
        select_onscreen_window(record);
        ScrollRect(&r, 0, num_rows * record->row_height, rh);
        EraseRgn(rh);
        SetEmptyRgn(rh);
    }
    if (num_columns) {
        pos_rect(record, &r, from_column, 0, record->x_size - 1,
                 record->y_size - 1);
        select_offscreen_port(record);
        ScrollRect(&r, num_columns * record->char_width, 0, rh);
        EraseRgn(rh);
        SetEmptyRgn(rh);
        select_onscreen_window(record);
        ScrollRect(&r, num_columns * record->char_width, 0, rh);
        EraseRgn(rh);
        SetEmptyRgn(rh);
    }
    DisposeRgn(rh);
    if (record->x_curs >= from_column) {
        record->x_curs += num_columns;
    }
    if (record->y_curs >= from_row) {
        record->y_curs += num_rows;
    }
    curs_pos(record, record->x_curs, record->y_curs, 1);

    return noErr;
}

/*
 * Frame an area in an aesthetically pleasing way.