Handle Application Crashes Better

Motivation

When dealing with application crashes, customers don't always send details of the crash when they report problems. They often don't realise they have to press the Details button, they dont tell you which version it is, or they might get Dr Watson dumps. Either way, you get either too much information, or not enough.

Having seen Martin Ziacek's article "SEH and C++ Exceptions - catch all in one" article, this provided me with a method to get better application crash handling.

Implementaion

Martin's article shows how to gain control after an Exception, what was needed was to present the information to the user. Firstly I added some code to traverse the stack in a backwards fashion, and collect all the adresses of all the calls.

void SeTranslator(UINT nSeCode, _EXCEPTION_POINTERS* pExcPointers)
{
	CSeException *se = new CSeException(nSeCode, pExcPointers);

	/*
	**  Save the last 32 functions called
	*/
	DWORD * sp = (DWORD *)(pExcPointers->ContextRecord->Ebp);
	for(int i=0;i<32;i++)
	{
		if(!IsBadReadPtr(sp,sizeof(DWORD)) && *sp)
		{
			DWORD *np = (DWORD *)*sp;
			se->m_StackTrace[i] = *(sp+1);

			sp = np;
		}
		else
			se->m_StackTrace[i] = 0;
	}
	throw se;
}

This way, when the application regains control after the throw, the stack at the time of the crash is known.

Implementation

All that is needed now is to present the crash details to the user. This is done by deriving your application object from CDumpHandleApp instead of CWinApp. CDumpHandleApp does the rest. In the InitInstance you need to add a call to the base class CDumpHandleApp::InitInstance and to set the support email address.

BOOL CDumpHandleDemoApp::InitInstance()
{
	/*
	**  Initialize the dumper code
	*/
	if(!CDumpHandleApp::InitInstance())
		return FALSE;

	m_strSupportEmail = "shyde@trontech.net";