Function pd_highlight_lines 

#[unsafe(no_mangle)]
pub extern "C" fn pd_highlight_lines(
    path_ptr: *const u8,
    path_len: u32,
    lines_ptr: *const u8,
    lines_len: u32,
) -> u64

Highlight a contiguous source-line run. lines is a JSON string array; Ok carries an HTML string array, or null for an unknown path.