//
// __CxxFrameHandler - Real entry point to the runtime
//
extern "C" _CRTIMP EXCEPTION_DISPOSITION __CxxFrameHandler(
EHExceptionRecord *pExcept, // Information for this exception
EHRegistrationNode *pFrame, // Dynamic information for this frame
void *pContext, // Context info
DispatcherContext *pDC // More dynamic info for this frame
) {
FuncInfo *pFuncInfo;
EXCEPTION_DISPOSITION result;
PFRAMEINFO pframeinfo;
if (!(IS_UNWINDING(PER_FLAGS(pExcept))) && ((unsigned long)pContext != (unsigned long)GetRTOC()) )
{
// we are calling catch from different CFM, re-initialize our globals
_pFrameInfoChain =(PFRAMEINFO) pDC->pftinfo->pFrameInfo;
_pftinfo->pFrameInfo = pDC->pftinfo->pFrameInfo;
cNested = 0;
pframeinfo = (PFRAMEINFO)_pftinfo->pFrameInfo;
while (pframeinfo)
{
cNested++;
pframeinfo = pframeinfo->pNext;
}
}
pFuncInfo = (FuncInfo*)pDC->FunctionEntry->HandlerData;
result = __InternalCxxFrameHandler( pExcept, pFrame, pContext, pDC, pFuncInfo, 0, NULL, FALSE );
return result;
}
void __stdcall _UnwindNestedFrames(
EHRegistrationNode *pRN, // Unwind up to (but not including) this frame
EHExceptionRecord *pExcept // The exception that initiated this unwind
) {
EHTRACE_ENTER;
void* pReturnPoint;
EHRegistrationNode *pDispatcherRN; // Magic!
__asm {
//
// Save the dispatcher's marker node
//
// NOTE: RtlUnwind will trash the callee-save regs EBX, ESI, and EDI.
// We explicitly use them here in the inline-asm so they get preserved
// and restored by the function prologue/epilogue.
//
mov esi, dword ptr FS:[0] // use ESI
mov pDispatcherRN, esi
}
__asm mov pReturnPoint, offset ReturnPoint
RtlUnwind(pRN, pReturnPoint, (PEXCEPTION_RECORD)pExcept, nullptr);
ReturnPoint:
PER_FLAGS(pExcept) &= ~EXCEPTION_UNWINDING; // Clear the 'Unwinding' flag
// in case exception is rethrown
__asm {
//
// Re-link the dispatcher's marker node
//
mov edi, dword ptr FS:[0] // Get the current head (use EDI)
mov ebx, pDispatcherRN // Get the saved head (use EBX)
mov [ebx], edi // Link saved head to current head
mov dword ptr FS:[0], ebx // Make saved head current head
}
EHTRACE_EXIT;
return;
}
void _UnwindNestedFrames(
EHRegistrationNode *pFrame, // Unwind up to (but not including) this frame
EHExceptionRecord *pExcept // The exception that initiated this unwind
//void *pContext // Context info for current exception
) {
PPMSTACK spCur;
PPMSTACK spCurCatch;
DispatcherContext curDC;
PFTINFO pftinfoTOC;
PRUNTIME_FUNCTION pFunctionEntry;
PRUNTIME_FUNCTION pFunctionEntryCatch = NULL;
unsigned long cNestedTmp;
PFRAMEINFO pframeinfo;
spCur = (PPMSTACK)GetSP();
//Loop through the frames backwards on the stack to destroy objects until target frame
//Assume:
spCur = spCur->pSpBackChain;
while (spCur < pFrame)
{
// we should only look the frame which hasn't been looked
if (_pFrameInfoChain)
{
if ((spCur > _pFrameInfoChain->pExitContext) && (spCur < _pFrameInfoChain->pSp))
{
spCur = spCur->pSpBackChain;
continue;
}
if (cNested > 0)
{
cNestedTmp = cNested;
pframeinfo = _pFrameInfoChain;
while (cNestedTmp-- && pframeinfo)
{
if ( (spCur->pSpBackChain == pframeinfo->pExitContext) )
{
pFunctionEntryCatch = GetFunctionEntry(spCur, &pftinfoTOC);
spCurCatch = spCur;
break;
}
pframeinfo = pframeinfo->pNext;
}
if (pframeinfo)
{
spCur = spCur->pSpBackChain;
continue;
}
}
}
pFunctionEntry = GetFunctionEntry(spCur, &pftinfoTOC);
if (pFunctionEntry && pFunctionEntry->ExceptionHandler != NULL)
{
//set unwinding flag
//stack point, old PC(in linker register, execution point==state), Registers in Context
PER_FLAGS(pExcept) |= EXCEPTION_UNWINDING;
curDC.ControlPc = spCur->dwLNKreg;
curDC.FunctionEntry = pFunctionEntry; //what else to save?!
curDC.EstablisherFrame = spCur;
curDC.pftinfo = pftinfoTOC;
if (pFunctionEntryCatch == pFunctionEntry)
{
// we have to update the return address in original catch frame
if (spCurCatch->dwLNKreg > curDC.ControlPc)
{
curDC.ControlPc = spCurCatch->dwLNKreg;
}
}
(*pFunctionEntry->ExceptionHandler)(pExcept, spCur, NULL, &curDC);
}
spCur = spCur->pSpBackChain;
}
//
// clear the unwinding flag, in case exception is rethown
//
PER_FLAGS(pExcept) &= ~EXCEPTION_UNWINDING;
return;
}
