While I won't say the ASN code is completely bug free (a debugged program is merely on for which the failing condition has not yet been found) it is also highly unlikely to be the source of your problem. The last bug was found in July, 2004!
What does tend to happen is the ASN code does a LOT of small memory allocations so is extremely susceptible to heap corruption. However the act of corrupting the heap could, unfortunately, be ANYWHERE. And at risk of causing offense, the most likely place is in your code. After all a lot of people use H323plus and even more use PTLib and are not seeing this crash.
This type of problem is notoriously difficult to find. The reason is that the crash point can have absolutely nothing to do with the cause of the crash which is in a completely different function and possibly even different TIME. The only way to fix them is divine inspiration and very good coding practices. The most common reasons are the "dangling pointer" and the "uninitialized pointer". If you don't know those terms go find a textbook and a better university.
Robert.
From: h323plus-bounces@lists.packetizer.com [mailto:h323plus-bounces@lists.packetizer.com] On Behalf Of mohammad alam Sent: Friday, 30 May 2008 12:01 AM To: H323plus Cc: cheersalam@yahoo.co.in Subject: [h323plus] Crash in Ptlib...........
Simon
After 8-10th times of placing and ending call (without restarting application) my Application crashes in ptlib in file asner.cxx at line 2079 (Below at line no.6 for your reference) Crashes are at both Local and Remote side on same line
1 PASN_Choice & PASN_Choice::operator=(const PASN_Choice & other) 2 { 3 if (&other == this) // Assigning to ourself, just do nothing. 4 return *this; 5 6 if(choice!=NULL) 7 { 8 delete choice; 9 choice = NULL; 10 } 11 12 PASN_Object::operator=(other); 13 14 numChoices = other.numChoices; 15 names = other.names; 16 namesCount = other.namesCount; 17 18 if (other.CheckCreate()) 19 choice = (PASN_Object *)other.choice->Clone(); 20 else 21 choice = NULL; 22 23 return *this; 24 }
I am using this in my Loadcapabilities function for H.263 CIF Image Size
capabilities.RemoveAll(); //called only once AddAllCapabilities(0, 0, "*"); //called only once AddAllUserInputCapabilities(0, 1); //called only once
preferenceorder.AppendString
(H263_CIF); preferenceorder.AppendString(H263_QCIF); preferenceorder.AppendString(H263_4CIF); preferenceorder.AppendString(H263_16CIF); preferenceorder.AppendString(H261_CIF); preferenceorder.AppendString(H261_QCIF); SetVideoFrameSize(H323Capability::cifMPI); capabilities.Reorder(preferenceorder);
The last few lines of PTRACE are
2:26.027 H225 Calle...er:22641e8 H225 Handling PDU: Connect callRef=11394 2:26.027 H225 Calle...er:22641e8 H225 Set protocol version to 6 and implying H.245 version 13 2:26.027 H225 Calle...er:22641e8 H225 Set remote party name: "admin" 2:26.027 H225 Calle...er:22641e8 H225 Set remote application name: " VCS 1.0.0 (H323plus v1.20beta3) 9/61" 2:26.027 H225 Calle...er:22641e8 H225 Received connect PDU. 2:26.027 H225 Calle...er:22641e8 H323TCP Connecting to 10.8.4.144:1412 http://10.8.4.144:1412/ (local port=0) 2:26.038 H225 Calle...er:22641e8 H323TCP SetOption(IP_TOS) failed: Invalid argument 2:26.038 H225 Calle...er:22641e8 H323TCP Started connection: host=10.8.4.144:1412 http://10.8.4.144:1412/ , if=10.8.4.148:2717 http://10.8.4.148:2717/ , handle=1280 2:26.038 H225 Calle...er:22641e8 H225 Fast Start FALSE fastStartState FastStartDisabled 2:26.038 H225 Calle...er:22641e8 H245 Handle control channel 2:26.038 H225 Calle...er:22641e8 H245 Start control negotiations 2:26.038 H225 Calle...er:22641e8 H245 Sending TerminalCapabilitySet: outSeq=1 2:26.038 H245:6f3ff60 H245 Started thread 2:26.038 H245:6f3ff60 H245 Handle control channel 2:26.038 H245:6f3ff60 H245 Start control negotiations
CRASH..>>>>>>>>>>>>>>>>>>>>>>
This crash is consistent. Crashes anytime after 5th call.. Your comments are needed. Where I am going wrong.....
Alam
Regards Mohammad Alam