[SOLVED] NFC and QProcess crash application

[andresteves]

Hi,

I've created an application that makes use of NFC, QProcess and HTTP requests.
The problem is that when i touch a tag it will make a HTTP request using QNetworkAccessManager and i got the response that will start an external application using @QProcess::startDetached(App)@ and put my application in the background with @CCoeEnv::Static()->RootWin().SetOrdinalPosition(-1);@ . I have started the application in debug with no breakpoints just to see what was the meaning of the error given after reading and launching the desired application. And it gives:

@dCODA CODA ->R|67|{"Code":16,"Time":1327054001764,"Format":"Invalid context ID"}||
eError retrieving register children of p2365.t2381: 'Invalid context ID' Code: 16
dCODA CODA <-C|68|RunControl|resume|"p2380.t2381"|0|1

*stopped,reason="signal-received",signal-name="SIGSEGV",signal-meaning="Segmentation fault",frame={addr="0x7d049bde",func="??",args=[]},thread-id="1",stopped-threads="all"@

The disassemble report:
@

~"Dump of assembler code from 0x7d049bca to 0x7d049c42:\n"
~" 0x7d049bca:\t\t\t; <UNDEFINED> instruction: 0xfa27bd7f\n"
~" 0x7d049bce:\tpush\t{r0, r4, r5, r6, r7, lr}\n"
~" 0x7d049bd0:\tsub\tsp, #24\n"
~" 0x7d049bd2:\tldr\tr1, [sp, #24]\n"
~" 0x7d049bd4:\tldr\tr0, [pc, #324]\t; (0x7d049d1c)\n"
~" 0x7d049bd6:\tstr\tr0, [r1, #0]\n"
~" 0x7d049bd8:\tldr\tr0, [sp, #24]\n"
~" 0x7d049bda:\tmovs\tr1, #8\n"
~" 0x7d049bdc:\tldr\tr5, [r0, #4]\n"
~"=> 0x7d049bde:\tldr\tr0, [r5, #16]\n"
~" 0x7d049be0:\torrs\tr0, r1\n"
~" 0x7d049be2:\tmovs\tr1, #4\n"
~" 0x7d049be4:\tbics\tr0, r1\n"
~" 0x7d049be6:\tstr\tr0, [r5, #16]\n"
~" 0x7d049be8:\tlsls\tr0, r0, #31\n"
~" 0x7d049bea:\tbne.n\t0x7d049bf2\n"
~" 0x7d049bec:\tldr\tr0, [sp, #24]\n"
~" 0x7d049bee:\tbl\t0x7d049b4a\n"
~" 0x7d049bf2:\tldr\tr0, [r5, #72]\t; 0x48\n"
~" 0x7d049bf4:\tmovs\tr4, r5\n"
~" 0x7d049bf6:\tadds\tr4, #72\t; 0x48\n"
~" 0x7d049bf8:\tmovs\tr6, #0\n"
~" 0x7d049bfa:\tcmp\tr0, #0\n"
~" 0x7d049bfc:\tbeq.n\t0x7d049c28\n"
~" 0x7d049bfe:\tldr\tr0, [r4, #0]\n"
@

It also gives me an error of @Thread has crashed: A data abort exception has occurred accessing 0x6576f375.@

Help please.

Best Regards,
Esteves

[andresteves]

Debug log also shows this:
@<94-exec-next-instruction
Thread 3010 stopped: 'Exception': A data abort exception has occurred accessing 0x6162776e.

94^running
dNOTE: INFERIOR RUN OK
dState changed from InferiorRunRequested(10) to InferiorRunOk(11).
*running,thread-id="all"
*stopped,reason="signal-received",signal-name="SIGSEGV",signal-meaning="Segmentation fault",frame={addr="0x7d04370e",func="??",args=[]},thread-id="1",stopped-threads="all"
dNOTE: INFERIOR SPONTANEOUS STOP
dState changed from InferiorRunOk(11) to InferiorStopOk(14).
dNOTE: INFERIOR SPONTANEOUS STOP
dState changed from InferiorStopOk(14) to InferiorStopOk(14).
dHANDLING SIGNALSIGSEGV
sStopped: Segmentation fault (Signal SIGSEGV).
<95-stack-list-frames
95^done,stack=[frame={level="0",addr="0x7d04370e",func="??"},frame={level="1",addr="0x7d0a4612",func="??"}]
<96-stack-select-frame 0@

[andresteves]

I can put any breakpoints in the middle of the code because while debugging i get NAK errors and then Qt Creator crash... Any Help Please?

[andresteves]

Solved :)

[ottokiksmaler]

Hi,

I'm facing very similar problem so I'm interested in how you managed to solve it. Debugger is of no use since qt-creator crashes...

Cheers,
Otto

[andresteves]

I changed the order of @QProcess@ with the @CCoeEnv::Static()->RootWin().SetOrdinalPosition(-1);@ and updated to Qt 4.8 and started to work by its own.

So probably the update correct some bugs and the code order had nothing to do with the solution.
Have you tried to update to 4.8?

Regards,
Andre

[ottokiksmaler]

I can not update to 4.8 since there is no 4.8 for symbian devices I'm developing for.

Thanks,
Otto