gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[Markus Schöpflin]

I'm toying around with gnoga, and I noticed that I get a SIGSEGV whenever I 
press "Exit Application" in any of the tutorials. Is this currently expected?

For tutorial 07, the call stack looks like this:

Program received signal SIGSEGV, Segmentation fault.
0x00000000005b0d7f in aws.net.websocket.send ()
(gdb) where
#0  0x00000000005b0d7f in aws.net.websocket.send ()
#1  0x0000000000473e3e in gnoga.server.connection.execute_script ()
#2  0x000000000041b419 in gnoga.gui.base.finalize ()
#3  0x0000000000424d33 in gnoga__gui__element__common__div_typeDF__2 ()
#4  0x0000000000405e3e in tutorial_07__app_dataDF.3335 ()
#5  0x0000000000406069 in tutorial_07__app_dataFD.3341 ()
#6  0x00000000006b66a2 in system.finalization_masters.finalize ()
#7  0x00000000004064b9 in tutorial_07___finalizer.2561 ()
#8  0x0000000000405d97 in tutorial_07 ()

This is on Ubuntu 14.04.1 LTS 64 bit, using GnatPro 7.2.2 and AWS 3.1.1.

Markus

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[David Botton]

> press "Exit Application" in any of the tutorials. Is this currently expected?

Not per se, I haven't seen it, but anything is possible. It has only been tested on debian and Mac OS X to any large extent.

Trying to Exit out of a heavily multi tasking environment cleanly is not easy especially where there are some quirks in AWS and GNAT with ATC.

I'll try and see what your error digs up on my search, but just give me a bit of patience on it for a few more weeks then I'll try and fire up a few VMs if needed to figure out where that is happening.

It does look to me though like it may be a race condition with Gnoga trying to communicate to the browser after the socket connection is lost or in the middle of closing. So I will reanalyze the code there.

David Botton

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[David Botton]

I believe I have resolved the issue with the latest commit. It should eliminate all issues related to finalization and shutdowns.

David Botton

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[Markus Schöpflin]

Am 07.10.2014 um 17:27 schrieb David Botton:

[...]

> I'll try and see what your error digs up on my search, but just give
> me a bit of patience on it for a few more weeks then I'll try and
> fire up a few VMs if needed to figure out where that is happening.

[...]

No worries. Are you interested in further problem reports at this point?

Markus

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[David Botton]

Very much so. I hope they are all so easy to fix as this was of course :)

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[Markus Schöpflin]

Am 07.10.2014 19:24, schrieb David Botton:
> I believe I have resolved the issue with the latest commit. It should
> eliminate all issues related to finalization and shutdowns.

Confirmed, all tutorials now exit cleanly when pressing the exit button.

BTW, tutorial 7 gives me an error when dragging and dropping the left on the 
right box. The border gets red OK but it doesn't turn green and shows the 
expected text. Firefox tries to load something instead and then displays an 
error page stating that the URL isn't valid and cannot be loaded. The 
websocket traffic looks normal, though. So maybe it's a problem with FF. If 
you want I can provide you with a short log of the websocket interactions.

Markus

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[David Botton]

Seems to be only of FF, I see the same behavior now on Mac when trying it. I'll see what can be done.

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[David Botton]

> Seems to be only of FF, I see the same behavior now on Mac when trying it. I'll see what can be done.

So far have not been able to see where the issue with FireFox is. I'll take a look again next week since I'll be offline soon for a few days.

David Botton

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[David Botton]

> So far have not been able to see where the issue with FireFox is. I'll take a look again next week since I'll be offline soon for a few days.

The issue was the default action on drop was not being prevented from firing. Fix is in.

Re: gnoga: SIGSEGV in aws.net.websocket.send() when exiting application

[Markus Schöpflin]

Am 12.10.2014 15:48, schrieb David Botton:
>> So far have not been able to see where the issue with FireFox is. I'll
>> take a look again next week since I'll be offline soon for a few days.
>
> The issue was the default action on drop was not being prevented from
> firing. Fix is in.
>
Works as advertised.