The previous "hangup cleanup" didn't accomplish much (other than to
give everyone a good view of extern.h). This one achieves more, and also
tries to fix the bug From a bug report:
> Buglet: Destroy old game -prompt can make game unrecoverable
>
> I haven't confirmed this myself, but few people playing on NAO
> have had the following happen:
> 1) play nethack
> 2) your network connection gets cut
> 3) reconnect, and get "Destroy old game" -prompt
> 4) your network connection gets cut, again, before you get to answer 'n'
> 5) game is not recoverable, because the level 0 file is gone.
The reason for #5 is simple to explain; it's the expected behavior of
current hangup() routine (although that hasn't always called clearlocks();
I don't know why it was added). The puzzle is why #2 left any lock files
around in the first place. I suspect it was because SAFERHANGUP defers
until rhack(), and rhack() doesn't get called if the hero is immobilized or
in the midst of a counted operation. I don't know how long a disconnected
process is allowed to run, but I don't think it's forever. (Alternatively,
nethack might be attempting further terminal I/O and getting stuck on the
hung connection; this won't help much if that's the case.)
This turns clearlocks() into a no-op during the period when the UNIX
port is asking the user to confirm whether to overwrite an existing game.
Also, this removes the duplication of code and function between hangup()
and end_of_input(), and it simplifies the check for whether hangups are
supported by adding new macro HANGUPHANDLING. (I don't think global.h is
the best place to be defining that but I couldn't figure out where else
it would fit, other than repeating for individual xxxconf.h files.) And
adds a couple more done_hup checks to try to cope with situations where
rhack() is being bypassed. Lastly, having readchar() return EOF was
ignored for non-UNIX configs; now everybody gets ESC instead of letting
EOF be seen further inside the core.
projects / nethack / commit