some debugging help needed

[Sebastian Reitenbach]

Hi,

still trying to fix problems when running OGo linked against 
gnustep-base. Thanks to Richard
at the Fosdem, I now know how to track down segfaults/exceptions due to 
multiple releases of an object
using the enableDoubleReleaseCheck and how to interpret the outcome.
.
That was already very helpful. However, I still have a problem, where it 
seems an already deallocated
object is accessed.
In the OGo menu, I can enter any category, like contacts, calendar, ... 
also the news. However, when
I leave the news, (whatever I click, also within the news page), I get 
the following exception:



Feb 09 21:51:32 ogo-webui-5.5 [12774]: [WARN] LSWImapMails could not 
determine context object!
Feb 09 21:51:32 ogo-webui-5.5 [12774]: [WARN] LSWImapMails missing 
session for component!
Feb 09 21:51:32 ogo-webui-5.5 [12774]: [WARN] LSWImapMails could not 
determine context object!
Feb 09 21:51:32 ogo-webui-5.5 [12774]: [WARN] LSWImapMails missing 
session for component!
^C[New process 12774]
^C
Program received signal SIGINT, Interrupt.
0x0d935bf5 in poll () from /usr/lib/libc.so.51.0
(gdb) break raise
[0] cancel
[1] all
[2] -[NSException raise] at NSException.m:831
[3] raise at /usr/src/lib/libc/gen/raise.c:37
> 2
Breakpoint 1 at 0x4aea46d: file NSException.m, line 831.
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
[Switching to process 12774, thread 0x8a85f000]
0x02fd40f8 in objc_msg_lookup (receiver=0x88a3d808, op=0x28d804b0) at 
sarray.h:230
230     sarray.h: No such file or directory.
       in sarray.h
(gdb) bt
#0  0x02fd40f8 in objc_msg_lookup (receiver=0x88a3d808, op=0x28d804b0) 
at sarray.h:230
#1  0x08d830e2 in -[WOApplication restoreSessionWithID:inContext:] 
(self=0x842f6308, _cmd=0x28d92830, _sid=0x7c07ec28, _ctx=0x7e3a9008)
   at WOApplication.m:588
#2  0x08dc0f51 in -[WORequestHandler handleRequest:] (self=0x8707ea48, 
_cmd=0x28d81548, _request=0x7cb8bb88) at WORequestHandler.m:193
#3  0x08d87bd1 in -[WOCoreApplication dispatchRequest:usingHandler:] 
(self=0x842f6308, _cmd=0x28d81580, _request=0x7cb8bb88, handler=0x8707ea48)
   at WOCoreApplication.m:704
#4  0x08d87eb7 in -[WOCoreApplication dispatchRequest:] 
(self=0x842f6308, _cmd=0x3c0060c8, _request=0x7cb8bb88) at 
WOCoreApplication.m:734
#5  0x1c00676f in -[OpenGroupware dispatchRequest:] (self=0x842f6308, 
_cmd=0x28db1510, _request=0x7cb8bb88) at OpenGroupware.m:829
#6  0x08e1b32e in -[WOHttpTransaction _run] (self=0x7c987c08, 
_cmd=0x28db1528) at WOHttpTransaction.m:546
#7  0x08e1b4b9 in -[WOHttpTransaction run] (self=0x7c987c08, 
_cmd=0x28db0888) at WOHttpTransaction.m:599
#8  0x08e179e8 in -[WOHttpAdaptor runConnection:] (self=0x836a3dc8, 
_cmd=0x28db08d8, _socket=0x7c39f0c8) at WOHttpAdaptor.m:403
#9  0x08e17bde in -[WOHttpAdaptor _handleAcceptedConnection:] 
(self=0x836a3dc8, _cmd=0x28db08e0, _connection=0x7c39f0c8) at 
WOHttpAdaptor.m:437
#10 0x08e182ee in -[WOHttpAdaptor _handleConnection:] (self=0x836a3dc8, 
_cmd=0x28db0968, connection=0x7c39f0c8) at WOHttpAdaptor.m:548
#11 0x08e185c3 in -[WOHttpAdaptor acceptConnection:] (self=0x836a3dc8, 
_cmd=0x28db0868, _notification=0x7c2895e8) at WOHttpAdaptor.m:604
#12 0x04b1e0b0 in -[NSNotificationCenter _postAndRelease:] 
(self=0x82eb6ca8, _cmd=0x24b1b0a8, notification=0x7c2895e8) at 
NSNotificationCenter.m:1070
#13 0x04b1e577 in -[NSNotificationCenter 
postNotificationName:object:userInfo:] (self=0x82eb6ca8, 
_cmd=0x24b1b0b0, name=0x23fbea84,
   object=0x836a3a48, info=0x0) at NSNotificationCenter.m:1129
#14 0x04b1e4a4 in -[NSNotificationCenter postNotificationName:object:] 
(self=0x82eb6ca8, _cmd=0x23fc0f88, name=0x23fbea84, object=0x836a3a48)
   at NSNotificationCenter.m:1109
#15 0x03fda031 in -[NSObject(FileObjectWatcher) 
receivedEvent:type:extra:forMode:] (self=0x836a3a48, _cmd=0x24b4a2b8, 
_fdData=0xa, _type=ET_RDESC,
   _extra=0xa, _mode=0x24b251bc) at NSRunLoop+FileObjects.m:57
#16 0x04bf39d6 in -[GSRunLoopCtxt pollUntil:within:] (self=0x819b4608, 
_cmd=0x24b250b0, milliseconds=29991, contexts=0x843d2fe8)
   at GSRunLoopCtxt.m:598
#17 0x04b5db5e in -[NSRunLoop acceptInputForMode:beforeDate:] 
(self=0x843d2f28, _cmd=0x24b250d8, mode=0x24b251bc, limit_date=0x7c2893c8)
   at NSRunLoop.m:1174
#18 0x04b5df80 in -[NSRunLoop runMode:beforeDate:] (self=0x843d2f28, 
_cmd=0x28d814b8, mode=0x24b251bc, date=0x7c067248) at NSRunLoop.m:1249
#19 0x08d875de in -[WOCoreApplication run] (self=0x842f6308, 
_cmd=0x28d8c8f0) at WOCoreApplication.m:576
#20 0x08dadbf2 in WOApplicationMain (_appClassName=0x3c005654, argc=7, 
argv=0xcfbf8430) at WOApplicationMain.m:42
---Type <return> to continue, or q <return> to quit---q
Quit
(gdb) frame 1
#1  0x08d830e2 in -[WOApplication restoreSessionWithID:inContext:] 
(self=0x842f6308, _cmd=0x28d92830, _sid=0x7c07ec28, _ctx=0x7e3a9008)
   at WOApplication.m:588
588           if ([session isNotNull]) {
Current language:  auto; currently objective-c
(gdb) list
583         if ((store = [self sessionStore]) == nil) {
584           [self errorWithFormat:@"missing session store ..."];
585         }
586         else {
587           session = [store restoreSessionWithID:_sid request:[_ctx 
request]];
588           if ([session isNotNull]) {
589             [_ctx setSession:session];
590             [session _awakeWithContext:_ctx];
591           }
592           else {
(gdb) print *session
$1 = {isa = 0xdeadface, wosLanguages = 0x83ffca08, isTerminating = 0 
'\000', wosLock = 0x0, wosSessionId = 0x7c289f08, wosVariables = 
0x89ceeb88,
 wosTimeOut = 3600, wosDefaultEditingContext = 0x0, wosFlags = 
{storesIDsInURLs = 1 '\001', storesIDsInCookies = 1 '\001', isAwake = 0 
'\000'},
 pageCache = {entries = 0x7c291800, index = 0, size = 30}, 
permanentPageCache = {entries = 0x7c291200, index = 0, size = 30}, 
application = 0x0,
 context = 0x0}
(gdb)


after some more research, I figured out that the isa = 0xdeadface points 
to an already deallocated object. After some more debugging, I figured out,
the deallocated object is a OGoSession. Therefore I put a breakpoint to 
-[OGoSession dealloc] in order to figure out where it is dellocated.
Restarting OGo, and then entering the News menu, the program stops at 
that breakpoint:
127.0.0.1 - - [09/Feb/2010:21:59:41 GMT] "POST 
/OpenGroupware.woa/x/login?da=&o=1265749110 HTTP/1.1" 200 5735/122 
64.461 37988 84% -
127.0.0.1 - - [09/Feb/2010:21:59:47 GMT] "GET 
/OpenGroupware.woa/x/dock?woinst=8294&wosid=20662066014B71CC7F&cid=0044b71cc7d7fbd1808&page=SkyNews 
HTTP/1.1" 200 5007/0 0.996 38067 86% -
[Switching to process 8294, thread 0x8aff6c00]

Breakpoint 1, -[OGoSession dealloc] (self=0x8b602c08, _cmd=0x212b88c0) 
at OGoSession.m:328
328       [[NSNotificationCenter defaultCenter]
Current language:  auto; currently objective-c
(gdb) bt
#0  -[OGoSession dealloc] (self=0x8b602c08, _cmd=0x212b88c0) at 
OGoSession.m:328
#1  0x012c4b0a in -[NSObject release] (self=0x8b602c08, _cmd=0x2129ff70) 
at NSObject.m:2036
#2  0x0123c62f in -[NSAutoreleasePool emptyPool] (self=0x80a30bc8, 
_cmd=0x2129ffd0) at NSAutoreleasePool.m:427
#3  0x0123c484 in -[NSAutoreleasePool dealloc] (self=0x80a30bc8, 
_cmd=0x2129ffc8) at NSAutoreleasePool.m:329
#4  0x0123c43f in -[NSAutoreleasePool release] (self=0x80a30bc8, 
_cmd=0x212bffa8) at NSAutoreleasePool.m:322
#5  0x012f8c13 in -[NSRunLoop acceptInputForMode:beforeDate:] 
(self=0x7fbd0e88, _cmd=0x212c00d8, mode=0x212c01bc, limit_date=0x7f077aa8)
   at NSRunLoop.m:1200
#6  0x012f8f80 in -[NSRunLoop runMode:beforeDate:] (self=0x7fbd0e88, 
_cmd=0x226464b8, mode=0x212c01bc, date=0x7f077aa8) at NSRunLoop.m:1249
#7  0x0264c5de in -[WOCoreApplication run] (self=0x845e7a08, 
_cmd=0x226518f0) at WOCoreApplication.m:576
#8  0x02672bf2 in WOApplicationMain (_appClassName=0x3c005654, argc=7, 
argv=0xcfbc2410) at WOApplicationMain.m:42
#9  0x0268f8cf in WOWatchDogApplicationMain (appName=0x3c005654, argc=7, 
argv=0xcfbc2410) at WOWatchDogApplicationMain.m:1017
#10 0x1c001db0 in gnustep_base_user_main (argc=7, argv=0xcfbc2410, 
env=0xcfbc2430) at main.m:33
#11 0x012e78b0 in main (argc=7, argv=0xcfbc2410, env=0xcfbc2430) at 
NSProcessInfo.m:921
#12 0x1c001c0c in ___start ()
#13 0x1c001b5f in _start ()
#14 0x00000000 in ?? ()

The first part in the backtrace where sth. is released is in 
NSRunLoop.m, frame 5:
(gdb) frame 5
#5  0x012f8c13 in -[NSRunLoop acceptInputForMode:beforeDate:] 
(self=0x7fbd0e88, _cmd=0x212c00d8, mode=0x212c01bc, limit_date=0x7f077aa8)
   at NSRunLoop.m:1200
1200      RELEASE(arp);
(gdb) list
1195          [context endPoll];
1196          [_contextStack removeObjectIdenticalTo: context];
1197          [localException raise];
1198        }
1199      NS_ENDHANDLER
1200      RELEASE(arp);
1201    }
1202
1203    /**
1204     * Calls -limitDateForMode: to determine if a timeout occurs 
before the

But I guess there is probably not the problem ;)

I wonder how I could track down the release of the session? What could 
cause calling [OGoSession dealloc] when
entering the News page in ogo, but not when I enter sth. else. Any hint 
where to set a breakpoint or anything would be great.

Thanks
Sebastian