Tracker: All unsafe blocks must be removed and then re-added one by one after careful verification of actual safety.#188

Using the FFI is `unsafe`, but simply putting `unsafe { }` around the call is not enough to get rid of the problem. It's unsafe for a reason. It's unsafe because it can do horrible things and cause UB. You need to adjust the library so that only functions that _cannot possibly_ cause UB, no matter what, are wrapped in an `unsafe` block and marked as safe. All other functions must be left as `unsafe` functions, hopefully with explanations in the docs of what to do to avoid problems.