This is a pretty big commit, so let's run through it in parts:
- All of the userspace changes are to switch away from syscall_wait
Mostly, this is to waitpid; some things were tweaked to do things
"properly" instead of waiting for particular processes. Init has
been fixed to do a proper spin wait.
- syscall_wait is gone - as are its uses. newlib bindings have been
using just waitpid for a while now.
- waitpid now performs like a Unix waitpid
- process reaping is no longer a "do this on next change thing":
it happens when a process is waited on, like it should
(That means we can have real zombies: terminated processes that
have not yet been waited on)
- Reparenting of children to init has been implemented, so you
can fork-daemonize!
Overall, this is pretty big... So I hope it doesn't break everything.
There are both some good changes and some terribly hacky changes in this
commit.
- Server uses a different struct than client now for windows, so
arbitrary compositor things like effect parameters can be added
without having to rebuild everything. That's good.
- Client window structs no longer attempt to track or use window
locations. That's good.
- Windows do not destroy in response to the destory command, but rather,
a special animation is triggered; the end state for this animation
calls the actually window destruction code. That's a hack.
- Animations are based on rendered frames, not on time. That's a hack.
Also, sleep() as a function (implemented by way of nanosleep) and new
absolute and relative sleep system calls added to newlib.
[ci skip] I damn well know this is going to break CI.
