In the first phase we collect a list of simple operations (copying
textures and filling rectangles.)
In the second phase we send this list to the graphics API to be
executed.
As part of this, we also remove the use of scissors.
There should no longer be any
- read
- write
- connect
- sendmsg
- recvmsg
- accept
calls in the codebase. Previously we were using a mix of io_uring and
these calls which had some negative effects: Since we were using the old
system calls, we had to set the file descriptors to non-blocking. But
our io_uring code did not handle EAGAIN. This lead to programs sometimes
being killed when the wayland IO was actually blocking.
Now all file descriptors are set to blocking, but io_uring makes it
non-blocking from our perspective. The one exception are evdev files
because they are read via libinput and libinput uses the old system
calls.
