switching the server to poll/epoll

[Adam Jackson]

On Wed, 2016-06-01 at 23:40 -0700, Keith Packard wrote:
> 
> And yet more changes to my poll/epoll work. Peter and I discovered that
> the threaded input code wasn't doing locking correctly, which was easy
> enough to fix on master, but required a bit more work with the new
> ospoll interface. That's all cleaned up now.
> 
> The series is longer now; I've found a few more things to clean up
> before and after making the major changes. There are now 21 patches
> before the poll code starts, four patches with the major changes, and
> then another six patches afterwards.

This series breaks the build at a few points. "Move ETEST macro from
io.c to osdep.h" needs to happen before "InputThreadFillPipe doesn't
need select or poll", since the latter uses ETEST. Everything between
"Switch server to poll(2)" to "Remove CheckConnections" fails to build
because CheckConnections doesn't know sizeof(pollfd).

Protip: git rebase -i -x make master

- ajax