/***
*trnsctrl.cpp -
*
* Copyright (c) 1990-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
*
*Revision History:
* 06-01-97 Created by TiborL.
* 07-12-99 RDL Image relative fixes under CC_P7_SOFT25.
* 10-07-99 SAH utc_p7#1126: fix ipsr.ri reset.
* 10-19-99 TGL Miscellaneous unwind fixes.
* 03-15-00 PML Remove CC_P7_SOFT25, which is now on permanently.
* 03-30-00 SAH New version of GetLanguageSpecificData from ntia64.h.
* 06-08-00 RDL VS#111429: IA64 workaround for AV while handling throw.
* 06-05-01 GB AMD64 Eh support Added.
*
****/
#if defined(_NTSUBSET_)
extern "C" {
#include <nt.h>
#include <ntrtl.h>
#include <nturtl.h>
#include <ntstatus.h> // STATUS_UNHANDLED_EXCEPTION
#include <ntos.h>
#include <ex.h> // ExRaiseException
}
#endif
extern "C" {
#include <windows.h>
};
#include <winnt.h>
#include <mtdll.h>
#include <ehassert.h>
#include <ehdata.h>
#include <trnsctrl.h>
#include <ehstate.h>
#include <eh.h>
#include <ehhooks.h>
#pragma hdrstop
#ifdef _MT
#define pFrameInfoChain (*((FRAMEINFO **) &(_getptd()->_pFrameInfoChain)))
#define pUnwindContext (*((CONTEXT **) &(_getptd()->_pUnwindContext)))
#define _ImageBase (_getptd()->_ImageBase)
#define _ThrowImageBase (_getptd()->_ThrowImageBase)
#define _pCurrentException (*((EHExceptionRecord **)&(_getptd()->_curexception)))
#else
static FRAMEINFO *pFrameInfoChain = NULL; // used to remember nested frames
static CONTEXT *pUnwindContext = NULL; // context to assist the return to 'UnwindNestedFrames'
static unsigned __int64 _ImageBase = 0;
static unsigned __int64 _ThrowImageBase = 0;
extern EHExceptionRecord *_pCurrentException;
#endif
// Should be used out of ntamd64.h, but can't figure out how to allow that with
// existing dependencies.
#define GetLanguageSpecificData(f, base) \
(((PUNWIND_INFO)(f->UnwindInfoAddress + base))->UnwindCode + ((((PUNWIND_INFO)(f->UnwindInfoAddress + base))->CountOfCodes + 1)&~1) +1)
extern "C" VOID RtlRestoreContext (PCONTEXT ContextRecord,PEXCEPTION_RECORD ExceptionRecord OPTIONAL);
extern "C" void RtlCaptureContext(CONTEXT*);
extern "C" void _GetNextInstrOffset(PVOID*);
extern "C" void __FrameUnwindToState(EHRegistrationNode *, DispatcherContext *, FuncInfo *, __ehstate_t);
//
// Returns the establisher frame pointers. For catch handlers it is the parent's frame pointer.
//
EHRegistrationNode *_GetEstablisherFrame(
EHRegistrationNode *pRN,
DispatcherContext *pDC,
FuncInfo *pFuncInfo,
EHRegistrationNode *pEstablisher
) {
TryBlockMapEntry *pEntry;
HandlerType *pHandler;
unsigned __int64 HandlerAdd, ImageBase;
unsigned num_of_try_blocks = FUNC_NTRYBLOCKS(*pFuncInfo);
unsigned index, i;
__ehstate_t curState;
curState = _StateFromControlPc(pFuncInfo, pDC);
*pEstablisher = *pRN;
for (index = num_of_try_blocks-1; (int)index >= 0; index--) {
pEntry = FUNC_PTRYBLOCK(*pFuncInfo, (index), pDC->ImageBase);
if (curState > TBME_HIGH(*pEntry) && curState <= TBME_CATCHHIGH(*pEntry)) {
// Get catch handler address.
HandlerAdd = (*RtlLookupFunctionEntry(pDC->ControlPc, &ImageBase, pDC->HistoryTable)).BeginAddress;
pHandler = TBME_PLIST(*pEntry, ImageBase);
for ( i = 0;
i < (unsigned)TBME_NCATCHES(*pEntry) &&
pHandler[i].dispOfHandler != HandlerAdd
; i++);
if ( i < (unsigned)TBME_NCATCHES(*pEntry)) {
*pEstablisher = *(EHRegistrationNode *)OffsetToAddress(pHandler[i].dispFrame, *pRN);
break;
}
}
}
return pEstablisher;
}
extern "C" VOID _SaveUnwindContext(CONTEXT* pContext)
{
pUnwindContext = pContext;
}
extern "C" CONTEXT* _GetUnwindContext()
{
return pUnwindContext;
}
extern "C" unsigned __int64 _GetImageBase()
{
return _ImageBase;
}
extern "C" unsigned __int64 _GetThrowImageBase()
{
return _ThrowImageBase;
}
extern "C" VOID _SetThrowImageBase(unsigned __int64 NewThrowImageBase)
{
_ThrowImageBase = NewThrowImageBase;
}
extern "C" VOID _MoveContext(CONTEXT* pTarget, CONTEXT* pSource)
{
RtlMoveMemory(pTarget, pSource, sizeof(CONTEXT));
}
// This function returns the try block for the given state if the state is in a
// catch; otherwise, NULL is returned.
static __inline TryBlockMapEntry *_CatchTryBlock(
FuncInfo *pFuncInfo,
__ehstate_t curState
) {
TryBlockMapEntry *pEntry;
unsigned num_of_try_blocks = FUNC_NTRYBLOCKS(*pFuncInfo);
unsigned index;
for (index = 0; index < num_of_try_blocks; index++) {
pEntry = FUNC_PTRYBLOCK(*pFuncInfo, index, _ImageBase);
if (curState > TBME_HIGH(*pEntry) && curState <= TBME_CATCHHIGH(*pEntry)) {
return pEntry;
}
}
return NULL;
}
//
// This routine returns TRUE if we are executing from within a catch. Otherwise, FALSE is returned.
//
BOOL _ExecutionInCatch(
DispatcherContext *pDC,
FuncInfo *pFuncInfo
) {
__ehstate_t curState = _StateFromControlPc(pFuncInfo, pDC);
return _CatchTryBlock(pFuncInfo, curState)? TRUE : FALSE;
}
// This function unwinds to the empty state.
VOID __FrameUnwindToEmptyState(
EHRegistrationNode *pRN,
DispatcherContext *pDC,
FuncInfo *pFuncInfo
) {
__ehstate_t stateFromControlPC;
TryBlockMapEntry *pEntry;
EHRegistrationNode EstablisherFramePointers, *pEstablisher;
pEstablisher = _GetEstablisherFrame(pRN, pDC, pFuncInfo, &EstablisherFramePointers);
stateFromControlPC = _StateFromControlPc(pFuncInfo, pDC);
pEntry = _CatchTryBlock(pFuncInfo, stateFromControlPC);
__FrameUnwindToState(pEstablisher, pDC, pFuncInfo,
pEntry == NULL ? EH_EMPTY_STATE : TBME_HIGH(*pEntry));
}
BOOL _IsExceptionObjectDestroyed(PVOID pExceptionObject,FRAMEINFO *pFrameInfo)
{
for (; pFrameInfo != NULL; pFrameInfo = pFrameInfo->pNext ) {
if( pFrameInfo->pExceptionObjectDestroyed == pExceptionObject ) {
return TRUE;
}
}
return FALSE;
}
void _MarkExceptionObjectDestroyed(EHExceptionRecord *pExcept)
{
for (FRAMEINFO *pFrameInfo = pFrameInfoChain; pFrameInfo != NULL; pFrameInfo = pFrameInfo->pNext ) {
if( pFrameInfo->pExcept == pExcept ) {
pFrameInfo->pExceptionObjectDestroyed = PER_PEXCEPTOBJ(pExcept);
}
}
}
void _UnlinkFrame(FRAMEINFO *pFrameInfo)
{
FRAMEINFO *pPrevFrameInfo = pFrameInfoChain;
if( pFrameInfoChain == pFrameInfo ) {
pFrameInfoChain = pFrameInfoChain->pNext;
return;
}
for (FRAMEINFO *pCurFrameInfo = pFrameInfoChain; pCurFrameInfo != NULL; pCurFrameInfo = pCurFrameInfo->pNext ) {
if( pCurFrameInfo == pFrameInfo ) {
pPrevFrameInfo->pNext = pCurFrameInfo->pNext;
return;
}
pPrevFrameInfo = pCurFrameInfo;
}
}
// Find the frame info structure corresponding to the given address. Return
// NULL if the frame info structure does not exist.
FRAMEINFO *_FindFrameInfo(
PVOID pContinuation,
FRAMEINFO *pFrameInfo
) {
unsigned __int64 ImageBase;
PRUNTIME_FUNCTION pContFunctionEntry = RtlLookupFunctionEntry((unsigned __int64)pContinuation, &ImageBase, NULL);
PRUNTIME_FUNCTION pFrameFunctionEntry = pFrameInfo->pFunctionEntry;
DASSERT(pFrameInfo != NULL);
for (; pFrameInfo != NULL; pFrameInfo = pFrameInfo->pNext ) {
if (pContFunctionEntry == pFrameInfo->pFunctionEntry &&
(pContinuation > OffsetToAddress(pFrameInfo->pFunctionEntry->BeginAddress,ImageBase)) &&
(pContinuation <= OffsetToAddress(pFrameInfo->pFunctionEntry->EndAddress,ImageBase))
){
return pFrameInfo;
}
}
return NULL;
}
BOOL __IsFramePdataMatch(
PVOID pContinuation,
RUNTIME_FUNCTION* pFrameRfe)
{
BOOL fRetVal = FALSE;
unsigned __int64 ImageBase;
PRUNTIME_FUNCTION pContRfe = RtlLookupFunctionEntry((unsigned __int64) pContinuation, &ImageBase, NULL);
FuncInfo* pContFuncInfo = (FuncInfo*)(_ImageBase + *(PULONG)GetLanguageSpecificData(pContRfe,_ImageBase));
FuncInfo* pFrameFuncInfo = (FuncInfo*)(ImageBase + *(PULONG)GetLanguageSpecificData(pFrameRfe,ImageBase));
//
// first see if there is a regular match, i.e. if the RFE registered with the frame
// matches the RFE for the continuation address
//
fRetVal = (pContRfe == pFrameRfe) &&
(pContinuation > OffsetToAddress(pFrameRfe->BeginAddress,ImageBase)) &&
(pContinuation <= OffsetToAddress(pFrameRfe->EndAddress,ImageBase));
if (!fRetVal && (pContFuncInfo->bbtFlags == BBT_UNIQUE_FUNCINFO)) {
fRetVal = (pContFuncInfo == pFrameFuncInfo);
}
return fRetVal;
}
//
// Given the address of a continuation point, return the corresponding context.
// Each frame info was saved just before a catch handler was called.
// The most recently encountered frame is at the head of the chain.
// The routine starts out with the frame given as the second argument, and scans the
// linked list for the frame that corresponds to the continuation point.
//
CONTEXT* _FindAndUnlinkFrame(PVOID pContinuation, FRAMEINFO *pFrameInfo)
{
DASSERT(pFrameInfo != NULL);
for( ; pFrameInfo != NULL; pFrameInfo = pFrameInfo->pNext ) {
if(__IsFramePdataMatch(pContinuation, pFrameInfo->pFunctionEntry)) {
//
// We found the frame.
// All frames preceeding and including this one are gone. so unlink them.
//
CONTEXT *pExitContext = pFrameInfo->pExitContext;
pFrameInfoChain = pFrameInfo->pNext;
//
// If there are no more exceptions pending get rid of unneeded frame info records.
//
if (_pCurrentException == NULL) {
while(pFrameInfoChain != NULL && pFrameInfoChain->pExceptionObjectDestroyed) {
pFrameInfoChain = pFrameInfoChain->pNext;
}
}
return pExitContext;
}
}
DASSERT(pFrameInfo != NULL);
return NULL;
}
//
// Save the frame information for this scope. Put it at the head of the linked-list.
//
FRAMEINFO* _CreateFrameInfo(
FRAMEINFO *pFrameInfo,
DispatcherContext *pDC,
CONTEXT *pExitContext,
__ehstate_t State,
PVOID pExceptionObjectDestroyed,
EHExceptionRecord *pExcept
) {
pFrameInfo->pFunctionEntry = pDC->FunctionEntry;
pFrameInfo->pExitContext = pExitContext;
pFrameInfo->pExceptionObjectDestroyed = pExceptionObjectDestroyed;
pFrameInfo->pExceptionObjectToBeDestroyed = NULL;
pFrameInfo->pExcept = pExcept;
pFrameInfo->State = State;
pFrameInfo->dtorThrowFlag = FALSE;
pFrameInfo->isRethrow = FALSE;
if( pFrameInfoChain != NULL && pFrameInfoChain->dtorThrowFlag ) {
pFrameInfoChain = pFrameInfoChain->pNext;
}
pFrameInfo->pNext = (pFrameInfo < pFrameInfoChain)? pFrameInfoChain : NULL;
pFrameInfoChain = pFrameInfo;
return pFrameInfo;
}
//
// THIS ROUTINE IS USED ONLY TO JUMP TO THE CONTINUATION POINT
//
// Sets SP and jumps to specified code address.
// Does not return.
//
void _JumpToContinuation(
unsigned __int64 TargetAddress, // The target address to call
CONTEXT *pContext, // Context of target function
EHExceptionRecord *pExcept
) {
pContext->Rip = TargetAddress;
RtlRestoreContext(pContext, (PEXCEPTION_RECORD)pExcept);
}
//
// Prototype for the internal handler
//
extern "C" EXCEPTION_DISPOSITION __InternalCxxFrameHandler(
EHExceptionRecord *pExcept, // Information for this exception
EHRegistrationNode *pRN, // Dynamic information for this frame
CONTEXT *pContext, // Context info
DispatcherContext *pDC, // More dynamic info for this frame
FuncInfo *pFuncInfo, // Static information for this frame
int CatchDepth, // How deeply nested are we?
EHRegistrationNode *pMarkerRN, // Marker node for when checking inside catch block
BOOL recursive); // True if this is a translation exception
//
// __CxxFrameHandler - Real entry point to the runtime
//
extern "C" _CRTIMP EXCEPTION_DISPOSITION __CxxFrameHandler(
EHExceptionRecord *pExcept, // Information for this exception
EHRegistrationNode RN, // Dynamic information for this frame
CONTEXT *pContext, // Context info
DispatcherContext *pDC // More dynamic info for this frame
) {
FuncInfo *pFuncInfo;
EXCEPTION_DISPOSITION result;
EHRegistrationNode EstablisherFrame = RN;
_ImageBase = pDC->ImageBase;
_ThrowImageBase = (unsigned __int64)pExcept->params.pThrowImageBase;
pFuncInfo = (FuncInfo*)(_ImageBase +*(PULONG)pDC->HandlerData);
result = __InternalCxxFrameHandler( pExcept, &EstablisherFrame, pContext, pDC, pFuncInfo, 0, NULL, FALSE );
return result;
}
// Call the SEH to EH translator.
BOOL _CallSETranslator(
EHExceptionRecord *pExcept, // The exception to be translated
EHRegistrationNode *pRN, // Dynamic info of function with catch
CONTEXT *pContext, // Context info
DispatcherContext *pDC, // More dynamic info of function with catch (ignored)
FuncInfo *pFuncInfo, // Static info of function with catch
ULONG CatchDepth, // How deeply nested in catch blocks are we?
EHRegistrationNode *pMarkerRN // Marker for parent context
) {
pRN;
pDC;
pFuncInfo;
CatchDepth;
// Call the translator.
_EXCEPTION_POINTERS excptr = { (PEXCEPTION_RECORD)pExcept, pContext };
__pSETranslator(PER_CODE(pExcept), &excptr);
// If we got back, then we were unable to translate it.
return FALSE;
}
//
// This structure is the FuncInfo (HandlerData) for handler __TranslatorGuardHandler
//
struct TransGuardRec {
FuncInfo *pFuncInfo; // Static info for subject function
EHRegistrationNode *pFrame; // Dynamic info for subject function
ULONG CatchDepth; // How deeply nested are we?
EHRegistrationNode *pMarkerFrame; // Marker for parent context
PVOID pContinue; // Continuation address within CallSEHTranslator
PVOID pSP; // SP within CallSEHTranslator
BOOL DidUnwind; // True if this frame was unwound
};
#if 0
//
// This routine is the handler for CallSETranslator which is defined in handlers.s
//
extern "C" _CRTIMP EXCEPTION_DISPOSITION __TranslatorGuardHandler(
EHExceptionRecord *pExcept, // Information for this exception
EHRegistrationNode *pFrame, // The translator guard frame
CONTEXT *pContext, // Context info
DispatcherContext *pDC // Dynamic info for this frame
) {
//
// The handler data is a pointer to an integer that is an offset to the TGRN structure
// relative to the frame pointer.
//
TransGuardRec *pTransGuardData = (TransGuardRec*)((char*)pFrame->MemoryStackFp - *(int*)(pDC->FunctionEntry->HandlerData));
if (IS_UNWINDING(PER_FLAGS(pExcept)))
{
pTransGuardData->DidUnwind = TRUE;
return ExceptionContinueSearch;
}
else {
//
// Check for a handler:
//
__InternalCxxFrameHandler( pExcept,
pTransGuardData->pFrame,
pContext,
pDC,
pTransGuardData->pFuncInfo,
pTransGuardData->CatchDepth,
pTransGuardData->pMarkerFrame,
TRUE );
// Unreached.
return ExceptionContinueSearch;
}
}
#endif
/////////////////////////////////////////////////////////////////////////////
//
// _GetRangeOfTrysToCheck - determine which try blocks are of interest, given
// the current catch block nesting depth. We only check the trys at a single
// depth.
//
// Returns:
// Address of first try block of interest is returned
// pStart and pEnd get the indices of the range in question
//
TryBlockMapEntry* _GetRangeOfTrysToCheck(
EHRegistrationNode *pRN,
FuncInfo *pFuncInfo,
int CatchDepth,
__ehstate_t curState,
unsigned *pStart,
unsigned *pEnd,
DispatcherContext *pDC
) {
TryBlockMapEntry *pEntry;
unsigned num_of_try_blocks = FUNC_NTRYBLOCKS(*pFuncInfo);
DASSERT( num_of_try_blocks > 0 );
for( unsigned int index = 0; index < num_of_try_blocks; index++ ) {
pEntry = FUNC_PTRYBLOCK(*pFuncInfo, index, pDC->ImageBase);
if( curState >= TBME_LOW(*pEntry) && curState <= TBME_HIGH(*pEntry) ) {
*pStart = index;
*pEnd = FUNC_NTRYBLOCKS(*pFuncInfo);
DASSERT( *pEnd <= num_of_try_blocks && *pStart < *pEnd );
int SavedState = GetUnwindTryBlock(pRN, pDC, pFuncInfo);
if( SavedState != -1 && SavedState >= curState )
continue;
return pEntry;
}
}
*pStart = *pEnd = 0;
return NULL;
}
#pragma optimize("",off)
extern "C" void _UnwindNestedFrames(
EHRegistrationNode *pFrame, // Unwind up to (but not including) this frame
EHExceptionRecord *pExcept, // The exception that initiated this unwind
CONTEXT *pContext, // Context info for current exception
DispatcherContext *pDC
) {
CONTEXT LocalContext; // Create context for this routine to return from RtlUnwind
CONTEXT ScratchContext; // Context record to pass to RtlUnwind2 to be used as scratch
volatile int Unwound = FALSE; // Flag that assist to return from RtlUnwind2
PVOID pReturnPoint = NULL; // The address we want to return from RtlUnwind2
RtlCaptureContext(&LocalContext);
//
// set up the return label
//
_GetNextInstrOffset(&pReturnPoint);
if(Unwound)
goto LAB_UNWOUND;
LocalContext.Rip = (ULONGLONG)pReturnPoint;
pUnwindContext = &LocalContext;
Unwound = TRUE;
#ifdef _NT
RtlUnwindEx((void *)*pFrame, (ULONG_PTR)pReturnPoint, (PEXCEPTION_RECORD)pExcept, NULL, &ScratchContext, pDC->HistoryTable);
#else
RtlUnwindEx((void *)*pFrame, pReturnPoint, (PEXCEPTION_RECORD)pExcept, NULL, &ScratchContext, pDC->HistoryTable);
#endif
LAB_UNWOUND:
PER_FLAGS(pExcept) &= ~EXCEPTION_UNWINDING;
pUnwindContext = NULL;
}