How to compress a directory to tar.xz with compression level and multithreading via CMake?

Question

I am trying to compress a directory as .tar.xz under Windows with CMake tools.

I want the following three things with priority in that order of importance:

1. The root directory of the tar should be different from my working directory.
2. Use maximum number of threads to speed up the compression.
3. Set the compression level.

I have found three ways to realize this:

• CMake file ARCHIVE_EXTRACT statement
  1. ❌ Can not set working directory (➕ workaround possible by sub-script call via execute_process)
  2. ❌ No multithreading support
  3. ✅ Can set compression level
• CMake tar command via execute_process
  1. ✅ Can set working directory (by execute_process)
  2. ❌ No multithreading support
  3. ❌ Can not set compression level
• CPack via execute_process
  1. ✅ Hopefully can set working directory (by execute_process?)
  2. ✅ Hopefully can enable multithreading support by CPACK_ARCHIVE_THREADS or CPACK_THREADS?
  3. ❌ Nothing found.

The first point I can apparently implement with any of these approaches. Multithreading seems to be possible only with the CPack approach.

Unfortunately I did not manage to implement the approach via cpack.

Is there any way to fulfill all three points or at least the first two ones?