Function nginx::SSL_set_msg_callback

pub unsafe extern "C" fn SSL_set_msg_callback(
    ssl: *mut SSL, 
    cb: Option<unsafe extern "C" fn(write_p: c_int, version: c_int, content_type: c_int, buf: *const c_void, len: size_t, ssl: *mut SSL, arg: *mut c_void)>
)