Fixes#6122, which reports a problem with trying to run the installer
under another user (probably: user is not the disk "owner" and thus
can't mount the volume).
This adds an explicit unmount of the store volume to avoid cases
where the installer can hang in await_volume when:
- the user already has a store volume
- that volume is already mounted somewhere other than /nix
- they do not take a path through the installer that results in an
explicit unmount (as both removing and encrypting the volume
would do)
As reported in #5198, volume creation can fail with a permission error
for some macOS users (probably secondary user accounts?) Sudo appears
to be sufficient to avoid this.
While I'm here, I also updated the sudo invocation added in 079bde2ae
to use the _sudo explanation wrapper.
As mentioned in previous commit, Big Sur changes the syntax for the
xpath command slightly.
In the process of testing out replacements for these, I noticed a few
small simplification wins.
This should handle installation scenarios we can handle with
anything resembling confidence. Goal is approximating the existing
setup--not enforcing a best-practice...
Approaches (+ installer-handled, - manual) and configs each covers:
+ no change needed; /nix OK on boot volume:
All pre-Catalina (regardless of T2 or FileVault use)
+ create new unencrypted volume:
Catalina, pre-T2, no FileVault
+ create new encrypted-at-rest volume:
Catalina, pre-T2, FileVault
Catalina, T2, no FileVault
- require user to pre-create encrypted volume
Catalina, T2, FileVault
Starting macOS 10.15 /nix can't be creasted directly anymore due to the
readonly filesystem, but synthetic.conf was introduced to enable
creating mountpoints or symlinks for special usecases like package
managers.
