Source code of Windows XP (NT5)
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/***
*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.
*
****/
#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 <mtdll.h>
#include <ehassert.h>
#include <ehdata.h>
#include <trnsctrl.h>
#include <ehstate.h>
#include <eh.h>
#include <ehhooks.h>
#include <kxia64.h>
#include <ia64inst.h>
#include <cvconst.h>
#pragma hdrstop
#ifdef _MT
#define pFrameInfoChain (*((FRAMEINFO **) &(_getptd()->_pFrameInfoChain)))
#define pUnwindContext (*((CONTEXT **) &(_getptd()->_pUnwindContext)))
#define _ImageBase (_getptd()->_ImageBase)
#define _TargetGp (_getptd()->_TargetGp)
#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;
static unsigned __int64 _TargetGp = 0;
extern EHExceptionRecord *_pCurrentException; // defined in frame.cpp
#endif
// Should be used out of ntia64.h, but can't figure out how to allow that with
// existing dependencies.
// If GetLanguageSpecificData changes cause a redefinition error rather than
// using wrong version.
// Version 2 = soft2.3 conventions
// Version 3 = soft2.6 conventions
#define GetLanguageSpecificData(f, base) \
((((PUNWIND_INFO)(base + f->UnwindInfoAddress))->Version <= 2) ? \
(((PVOID)(base + f->UnwindInfoAddress + sizeof(UNWIND_INFO) + \
((PUNWIND_INFO)(base+f->UnwindInfoAddress))->DataLength*sizeof(ULONGLONG) + sizeof(ULONGLONG)))) : \
(((PVOID)(base + f->UnwindInfoAddress + sizeof(UNWIND_INFO) + \
((PUNWIND_INFO)(base+f->UnwindInfoAddress))->DataLength*sizeof(ULONGLONG) + sizeof(ULONG)))))
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;
unsigned num_of_try_blocks = FUNC_NTRYBLOCKS(*pFuncInfo);
unsigned index;
__ehstate_t curState;
curState = _StateFromControlPc(pFuncInfo, pDC);
pEstablisher->MemoryStackFp = pRN->MemoryStackFp;
pEstablisher->BackingStoreFp = pRN->BackingStoreFp;
for (index = 0; index < num_of_try_blocks; index++) {
pEntry = FUNC_PTRYBLOCK(*pFuncInfo, index, pDC->ImageBase);
if (curState > TBME_HIGH(*pEntry) && curState <= TBME_CATCHHIGH(*pEntry)) {
pEstablisher->MemoryStackFp = *(__int64 *)OffsetToAddress(-8,pRN->MemoryStackFp);
pEstablisher->BackingStoreFp = *(__int64 *)OffsetToAddress(-16,pRN->BackingStoreFp);
break;
}
}
return pEstablisher;
}
#if 0 // v-vadimp new version with NLG support for the debugger is in handlers.s
//
// Temporary version until the asm version is written that supports NLG
//
extern "C" void* _CallSettingFrame(
void* handler,
EHRegistrationNode *pEstablisher,
ULONG NLG_CODE)
{
void* retValue = __Cxx_ExecuteHandler(
pEstablisher->MemoryStackFp,
pEstablisher->BackingStoreFp,
(__int64)handler,
_TargetGp
);
return retValue? (void*)(_ImageBase + (__int32)retValue) : NULL;
}
#endif
extern "C" CONTEXT* _GetUnwindContext()
{
return pUnwindContext;
}
extern "C" unsigned __int64 _GetImageBase()
{
return _ImageBase;
}
extern "C" VOID _SetImageBase(unsigned __int64 ImageBaseToRestore)
{
_ImageBase = ImageBaseToRestore;
}
extern "C" unsigned __int64 _GetThrowImageBase()
{
return _ThrowImageBase;
}
extern "C" VOID _SetThrowImageBase(unsigned __int64 NewThrowImageBase)
{
_ThrowImageBase = NewThrowImageBase;
}
extern "C" unsigned __int64 _GetTargetGP(unsigned __int64 TargetAddress)
{
unsigned __int64 ImageBase;
unsigned __int64 TargetGp;
PRUNTIME_FUNCTION pContFunctionEntry = RtlLookupFunctionEntry(TargetAddress, &ImageBase, &TargetGp);
// return _TargetGp;
return TargetGp;
}
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);
// Reuse pFrameInfoChain->State to propagate the previous catch block's final state.
// This is used in case there is a nested catch inside this catch
// who already dtored object's in our frame. This can happen if in our catch
// there is a nested catch that throws and the catch executed is an outer catch.
//
//try{
// try{
// throw(1);
// }catch(int){
// B b4;
// try{
// throw 2;
// }catch(int){
// //this throw would dtor b4 by calling the outermost catch,
// //and also during unwinding the first catch would try to dtor as well.
// throw 3;
// }
// }
//}catch(int){
// throw 4;
//}
//
if( pEntry && pFrameInfoChain != NULL ) {
__ehstate_t curState = GetCurrentState(pEstablisher, pDC, pFuncInfo);
if( pFrameInfoChain->State != -2 && pFrameInfoChain->State < curState )
SetState(pEstablisher, pDC, pFuncInfo, pFrameInfoChain->State);
pFrameInfoChain->State = curState;
}
else if( pFrameInfoChain != NULL ) {
__ehstate_t curState = GetCurrentState(pEstablisher, pDC, pFuncInfo);
if( pEntry == NULL && stateFromControlPC < curState ) {
SetState(pEstablisher, pDC, pFuncInfo, stateFromControlPC - 1);
}
pFrameInfoChain->State = -2;
}
__FrameUnwindToState(pEstablisher, pDC,
pFuncInfo, pEntry == NULL ? EH_EMPTY_STATE : TBME_HIGH(*pEntry) /*+ 1*/);
}
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;
unsigned __int64 TargetGp;
PRUNTIME_FUNCTION pContFunctionEntry = RtlLookupFunctionEntry((unsigned __int64)pContinuation, &ImageBase, &TargetGp);
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, TargetGp;
PRUNTIME_FUNCTION pContRfe = RtlLookupFunctionEntry((unsigned __int64) pContinuation, &ImageBase, &TargetGp);
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 are 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->dtorThrowFlag = FALSE;
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
) {
unsigned __int64 ImageBase;
unsigned __int64 TargetGp;
PRUNTIME_FUNCTION pFunctionEntry = RtlLookupFunctionEntry(TargetAddress, &ImageBase, &TargetGp);
pContext->StIIP = TargetAddress;
pContext->IntGp = TargetGp;
pContext->StIPSR &= ~IPSR_RI_MASK;
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
__int64 MemoryStackFp, // SP of user program
__int64 BackingStoreFp, // BSP of user program
CONTEXT *pContext, // Context info
DispatcherContext *pDC, // More dynamic info for this frame
__int64 TargetGp // GP of user program
) {
FuncInfo *pFuncInfo;
EXCEPTION_DISPOSITION result;
EHRegistrationNode EstablisherFrame = { MemoryStackFp, BackingStoreFp };
_ImageBase = pDC->ImageBase;
_TargetGp = TargetGp;
_ThrowImageBase = (unsigned __int64)pExcept->params.pThrowImageBase;
pFuncInfo = (FuncInfo*)(_ImageBase + *(PULONG)GetLanguageSpecificData(pDC->FunctionEntry, _ImageBase));
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 );
#if 1
int SavedState = GetUnwindTryBlock(pRN, pDC, pFuncInfo);
if( SavedState != -1 && SavedState >= curState )
continue;
#else
int SavedTryNdx = GetUnwindTryBlock(pRN, pDC, pFuncInfo);
if( SavedTryNdx != -1 ) {
*pStart = SavedTryNdx + 1;
if( *pStart < *pEnd && pEntry != NULL ) {
pEntry = FUNC_PTRYBLOCK(*pFuncInfo, SavedTryNdx + 1, pDC->ImageBase);
}
}
#endif
return pEntry;
}
}
*pStart = *pEnd = 0;
return NULL;
}
#pragma optimize("",off)
extern "C" unsigned __int64 __getReg(int);
extern "C" void __setReg(int, unsigned __int64);
#pragma intrinsic(__getReg)
#pragma intrinsic(__setReg)
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
) {
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.StIIP = (ULONGLONG)pReturnPoint;
LocalContext.IntGp = __getReg(CV_IA64_IntR1);
LocalContext.StIPSR &= ~IPSR_RI_MASK;
pUnwindContext = &LocalContext; // save address of LocalContext in global/TLS pUnwindContext
Unwound = TRUE;
#ifdef _NT
RtlUnwind2(*pFrame, (ULONG_PTR)pReturnPoint, (PEXCEPTION_RECORD)pExcept, NULL, &ScratchContext);
#else
RtlUnwind2(*pFrame, pReturnPoint, (PEXCEPTION_RECORD)pExcept, NULL, &ScratchContext);
#endif
LAB_UNWOUND:
__setReg(CV_IA64_IntR1,LocalContext.IntGp);
pContext->StIPSR &= ~IPSR_RI_MASK;
PER_FLAGS(pExcept) &= ~EXCEPTION_UNWINDING;
//
// reset global/TLS pUnwindContext for future exceptions
//
pUnwindContext = NULL;
}