[Xastir] {Disarmed} Re: objects getting scrambled

[Mike Swiatkowski, AA9VI]

Tom (and Curt),
FYI, TNC is in serial mode.  But no logging or snapshots are checked under the File menu.

There appears to be a bug.  I had to restart Xastir again today.  I thought I could workaround the bug by putting the objects into the TNC and not using Xastir, but it ends up sending the objects twice, even though I don't tell Xastir to send them.  Seems Xastir has some smarts to take objects originated from the TNC and put it into it's Xastir object file and then sends out its own version.

Here are some examples object name Shmbg-DMR that get sent out due to this bug:
 Shkbg-DMR Shkbg-lMR Shmbg-$MR Shmbg-BMR Shmbg-DMQ Shmng-BMR Shmng.DMR ShmRg-DMR Shmzg-DKR

The actual text of the object is considerably messed up too like the object name.



Mike, AA9VI

-----------------------------------------------------------------------------------
Message: 1
Date: Thu, 15 Sep 2011 13:06:51 -0600
From: Tom Russo <russo at bogodyn.org>
To: Xastir - APRS client software discussion <xastir at lists.xastir.org>
Subject: Re: [Xastir] objects getting scrambled
Message-ID: <20110915190651.GA50642 at bogodyn.org>
Content-Type: text/plain; charset=us-ascii

On Thu, Sep 15, 2011 at 08:51:38AM -0700, we recorded a bogon-computron collision of the <aa9vi at yahoo.com> flavor, containing:
>
 I am having issues on 2.0.1 with my objects from AA9VI-13 getting all 
scrambled from time to time.? Sometimes the object name gets funny 
characters, sometimes the object text gets some wrong characters or 
loses characters all together.? Any idea why this is happening?? I use a
 KPC3+ and I am running Debian 6.
> 
> A shutdown and 
restart of Xastir cleans this up for a short period of time.? It's like 
the .cnf file or whatever stores the object info is getting fouled up.? 
Weird.? Should I just blow the installation away and go to stable 
v2.0.0? Thanks for your feedback.? 


I've not seen this, but I have seen something similar and perplexing.  Perhaps
they are related.

Do you have multiple check boxes under the File menu set, e.g. for PNG 
snapshots, logging, etc.?

When I had both PNG snaphots and TNC logging turned on, I found that some
configuration did indeed get scrambled --- in my case, it was the path names
for snapshots, which would become completely corrupted.  If I attempted to quit
Xastir, it would give error messages about not being able to write the .cnf
file out (because the path was corrupted).  My guess is that there
is some non-thread-safe code that scribbles into arrays, and when there are
multiple timed writes like snapshots and logging, the two acts corrupt each 
other in some instances.  I was never able to track it down, but the behavior
went away when I turned off TNC logging (I run PNG snapshots continuously,
which I upload to a web site every 5-10 mins).

So, if you have two or more logging/snapshot options selected, try shutting
off all but one of them and see if the behavior changes.  If so, then it may
be the same issue that bit me.

I wish I could have tracked it down, but since it's a random event it was 
pretty much impossible to work through in finite time.

-- 
Tom Russo    KM5VY   SAR502   DM64ux          http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236        http://kevan.org/brain.cgi?DDTNM
 "One man alone can be pretty dumb sometimes, but for real bona fide
 stupidity, there ain't nothin' can beat teamwork." - Edward Abbey