[Xastir] HSP/AUX/Timings etc.

[Alan Crosswell]

I've previously reported segfaults in Imagemagick code.  Something that's 
supposed to return a pointer returns NULL.  gdb it and see where the fault happens.

/a

Curt Mills, WE7U wrote:
> On Tue, 15 Jul 2003, Stephen West-Fisher wrote:
> 
> 
>>First, more of a comment about how I fixed it, and what is next. I did a
>>very bad programmer thing (I've been known to get harsh with programmers
>>who work for me and do this) and just copied another section of code,
>>made a few little modifications, and it worked.
> 
> 
> Guess how most of Xastir was extended to add new features?  ;-)
> 
> 
> 
>>Looking at the code, it looks like the HSP stuff is an extention of the
>>normal serial GPS stuff. However, it also appears a better use of code
>>would be to treat the HSP code as an extention of the AUX code. In both
>>HSP and AUX all data goes into the same buffer and is parsed from there.
>>I'm going to give this a try when I get a chance.
> 
> 
> That sounds reasonable.  I think HSP was added after serial, and
> then AUX came later.
> 
> 
> 
>>Secondly, I'm still having the odd Segfault, but it may be my crappy
>>code modification above. Origionaly I thought it was happening on the
>>GPS strings, but this morning I had one on a digi of my beacon.
> 
> 
> Were you doing map interrupts at the time?  Tigermap stuff?  What
> was different at the time you had the segfaults?  Do they happen
> even when you're doing nothing, and not tracking anyone (as in maps
> are static)?
> 
> Gerry seems to think that interrupting tigermap draws might cause
> them to happen.  I haven't seen any segfaults here no matter what I
> try.  If I could reproduce them at will, I could solve them.
> 
> 
> 
>>Third, the timing issue I had brought up earlier. I'm now not so sure it
>>is a problem, but Curt's idea of a timeout when reading the GPS may be
>>needed in the HSP code. Last night I was getting very frustrated because
>>the DTR was getting stuck low no matter what I did. When I decided to
>>give up for the night, I noticed the GPS had lost sync. So my theory for
>>today is that when Xastir gets stuck with DTR low, the GPS has lost
>>signal.
> 
> 
> That is correct.  I looked through the code a few days back and
> that's what it does.  It was intended to be a "feature" that you
> switch back to TNC mode as quickly as possible, meaning as soon as
> you parse good GPS strings the switch occurs.  As it stands, if the
> GPS becomes disconnected or loses lock, you stay in GPS mode.  That
> wasn't the intention.  I'll look into changing that.
> 
> I'll put in a bug report on that very thing.
>