migrate: don't allow migrating more than once and if not migrated at boot

[IAmTheNerdNextDoor]

Prevents migrate from breaking ToaruOS and making it unusable if used outside of the boot process. This prevents the user from running migrate if migrate isn't in the cmdline at boot and prevents them from migrating again by using an invisible file marker check.

Came up with this for my own local fork of ToaruOS last week.

[klange]

The usual way I prevent silly mistakes by explorative users is to require a --really argument on things that shouldn't be manual run.

With migrate, I think a better option than having a file sitting around is to detect the conditions for which migration should have already happened, like the root filesystem being a tmpfs.

[IAmTheNerdNextDoor]

With migrate, I think a better option than having a file sitting around is to detect the conditions for which migration should have already happened, like the root filesystem being a tmpfs.

Hmm, I'll see what I can do there. I'm not sure how to check if it's tmpfs in code but I'll try to find out how.

[klange]

The main way would be to look at /proc/mounts, though the current format is a bit awkward for parsing, especially with the tree layout.

[IAmTheNerdNextDoor]

Right, I've tested this and it works on my fork. Lemme know what you think.

[klange]

I should have mentioned I am thinking of improving the formatting of /proc/mounts, so relying on the current formatting is not a good idea either. Nothing else currently depends on it (that I know of - always possible someone has some Toaru tooling floating around I'm blissfully unaware of). Let me get back to you on this in a bit.

[IAmTheNerdNextDoor]

I should have mentioned I am thinking of improving the formatting of /proc/mounts, so relying on the current formatting is not a good idea either. Nothing else currently depends on it (that I know of - always possible someone has some Toaru tooling floating around I'm blissfully unaware of). Let me get back to you on this in a bit.

Alright then, looking forward to hearing from you again!

[IAmTheNerdNextDoor]

Hey, just commenting to see how you are and if there's any updates on this PR. No rush of course!