Function logcheck_filter_json 

#[unsafe(no_mangle)]
pub extern "C" fn logcheck_filter_json(
    _tag: *const c_char,
    _tag_len: usize,
    _time_sec: u32,
    _time_nsec: u32,
    record: *const c_char,
    record_len: usize,
) -> *const c_char

Main logcheck filter function for JSON format Returns: Modified JSON record with logcheck metadata, or NULL to drop the record