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Diffstat (limited to 'private/ntos/rtl/i386/xcptmisc.asm')
| -rw-r--r-- | private/ntos/rtl/i386/xcptmisc.asm | 612 |
1 files changed, 612 insertions, 0 deletions
diff --git a/private/ntos/rtl/i386/xcptmisc.asm b/private/ntos/rtl/i386/xcptmisc.asm new file mode 100644 index 000000000..c4c0489c8 --- /dev/null +++ b/private/ntos/rtl/i386/xcptmisc.asm @@ -0,0 +1,612 @@ + title "Miscellaneous Exception Handling" +;++ +; +; Copyright (c) 1989 Microsoft Corporation +; +; Module Name: +; +; xcptmisc.asm +; +; Abstract: +; +; This module implements miscellaneous routines that are required to +; support exception handling. Functions are provided to call an exception +; handler for an exception, call an exception handler for unwinding, get +; the caller's stack pointer, get the caller's frame pointer, get the +; caller's floating status, get the caller's processor state, get the +; caller's extended processor status, and get the current stack limits. +; +; Author: +; +; David N. Cutler (davec) 14-Aug-1989 +; +; Environment: +; +; Any mode. +; +; Revision History: +; +; 6 April 90 bryanwi +; +; 386 version created +; +;-- +.386p + + .xlist +include ks386.inc +include callconv.inc ; calling convention macros + .list + +; +; Unwind flags. +; + +Unwind equ EXCEPTION_UNWINDING OR EXCEPTION_EXIT_UNWIND + +_TEXT$01 SEGMENT DWORD PUBLIC 'CODE' + ASSUME DS:FLAT, ES:FLAT, SS:NOTHING, FS:NOTHING, GS:NOTHING + + page + subttl "Execute Handler for Exception" +;++ +; +; EXCEPTION_DISPOSITION +; RtlpExecuteHandlerForException ( +; IN PEXCEPTION_RECORD ExceptionRecord, +; IN PVOID EstablisherFrame, +; IN OUT PCONTEXT ContextRecord, +; IN OUT PVOID DispatcherContext, +; IN PEXCEPTION_ROUTINE ExceptionRoutine +; ) +; +; Routine Description: +; +; This function allocates a call frame, stores the handler address and +; establisher frame pointer in the frame, establishes an exception +; handler, and then calls the specified exception handler as an exception +; handler. If a nested exception occurs, then the exception handler of +; of this function is called and the handler address and establisher +; frame pointer are returned to the exception dispatcher via the dispatcher +; context parameter. If control is returned to this routine, then the +; frame is deallocated and the disposition status is returned to the +; exception dispatcher. +; +; Arguments: +; +; ExceptionRecord (ebp+8) - Supplies a pointer to an exception record. +; +; EstablisherFrame (ebp+12) - Supplies the frame pointer of the establisher +; of the exception handler that is to be called. +; +; ContextRecord (ebp+16) - Supplies a pointer to a context record. +; +; DispatcherContext (ebp+20) - Supplies a pointer to the dispatcher context +; record. +; +; ExceptionRoutine (ebp+24) - supplies a pointer to the exception handler +; that is to be called. +; +; Return Value: +; +; The disposition value returned by the specified exception handler is +; returned as the function value. +; +;-- + +cPublicProc _RtlpExecuteHandlerForException,5 + + mov edx,offset FLAT:ExceptionHandler ; Set who to register + jmp ExecuteHandler ; jump to common code + +stdENDP _RtlpExecuteHandlerForException + + + page + subttl "Execute Handler for Unwind" +;++ +; +; EXCEPTION_DISPOSITION +; RtlpExecuteHandlerForUnwind ( +; IN PEXCEPTION_RECORD ExceptionRecord, +; IN PVOID EstablisherFrame, +; IN OUT PCONTEXT ContextRecord, +; IN OUT PVOID DispatcherContext, +; IN PEXCEPTION_ROUTINE ExceptionRoutine +; ) +; +; Routine Description: +; +; This function allocates a call frame, stores the handler address and +; establisher frame pointer in the frame, establishes an exception +; handler, and then calls the specified exception handler as an unwind +; handler. If a collided unwind occurs, then the exception handler of +; of this function is called and the handler address and establisher +; frame pointer are returned to the unwind dispatcher via the dispatcher +; context parameter. If control is returned to this routine, then the +; frame is deallocated and the disposition status is returned to the +; unwind dispatcher. +; +; Arguments: +; +; ExceptionRecord (ebp+8) - Supplies a pointer to an exception record. +; +; EstablisherFrame (ebp+12) - Supplies the frame pointer of the establisher +; of the exception handler that is to be called. +; +; ContextRecord (ebp+16) - Supplies a pointer to a context record. +; +; DispatcherContext (ebp+20) - Supplies a pointer to the dispatcher context +; record. +; +; ExceptionRoutine (ebp+24) - supplies a pointer to the exception handler +; that is to be called. +; +; Return Value: +; +; The disposition value returned by the specified exception handler is +; returned as the function value. +; +;-- + +cPublicProc _RtlpExecuteHandlerForUnwind ,5 + + mov edx,offset FLAT:UnwindHandler + +;; N.B. - FALL into ExecuteHandler + +stdENDP _RtlpExecuteHandlerForUnwind + + + +; +; ExecuteHandler is the common tail for RtlpExecuteHandlerForException +; and RtlpExecuteHandlerForUnwind. +; +; (edx) = handler (Exception or Unwind) address +; + + +ExceptionRecord equ [ebp+8] +EstablisherFrame equ [ebp+12] +ContextRecord equ [ebp+16] +DispatcherContext equ [ebp+20] +ExceptionRoutine equ [ebp+24] + + +cPublicProc ExecuteHandler,5 + + push ebp + mov ebp,esp + + push EstablisherFrame ; Save context of exception handler + ; that we're about to call. + + .errnz ErrHandler-4 + push edx ; Set Handler address + + .errnz ErrNext-0 + push fs:PcExceptionList ; Set next pointer + + + mov fs:PcExceptionList,esp ; Link us on + +; Call the specified exception handler. + + push DispatcherContext + push ContextRecord + push EstablisherFrame + push ExceptionRecord + + mov ecx,ExceptionRoutine + call ecx + mov esp,fs:PcExceptionList + +; Don't clean stack here, code in front of ret will blow it off anyway + +; Disposition is in eax, so all we do is deregister handler and return + + .errnz ErrNext-0 + pop fs:PcExceptionList + + mov esp,ebp + pop ebp + stdRET ExecuteHandler + +stdENDP ExecuteHandler + + page + subttl "Local Exception Handler" +;++ +; +; EXCEPTION_DISPOSITION +; ExceptionHandler ( +; IN PEXCEPTION_RECORD ExceptionRecord, +; IN PVOID EstablisherFrame, +; IN OUT PCONTEXT ContextRecord, +; IN OUT PVOID DispatcherContext +; ) +; +; Routine Description: +; +; This function is called when a nested exception occurs. Its function +; is to retrieve the establisher frame pointer and handler address from +; its establisher's call frame, store this information in the dispatcher +; context record, and return a disposition value of nested exception. +; +; Arguments: +; +; ExceptionRecord (exp+4) - Supplies a pointer to an exception record. +; +; EstablisherFrame (esp+8) - Supplies the frame pointer of the establisher +; of this exception handler. +; +; ContextRecord (esp+12) - Supplies a pointer to a context record. +; +; DispatcherContext (esp+16) - Supplies a pointer to the dispatcher context +; record. +; +; Return Value: +; +; A disposition value ExceptionNestedException is returned if an unwind +; is not in progress. Otherwise a value of ExceptionContinueSearch is +; returned. +; +;-- + +stdPROC ExceptionHandler,4 + + mov ecx,dword ptr [esp+4] ; (ecx) -> ExceptionRecord + test dword ptr [ecx.ErExceptionFlags],Unwind + mov eax,ExceptionContinueSearch ; Assume unwind + jnz eh10 ; unwind, go return + +; +; Unwind is not in progress - return nested exception disposition. +; + + mov ecx,[esp+8] ; (ecx) -> EstablisherFrame + mov edx,[esp+16] ; (edx) -> DispatcherContext + mov eax,[ecx+8] ; (eax) -> EstablisherFrame for the + ; handler active when we + ; nested. + mov [edx],eax ; Set DispatcherContext field. + mov eax,ExceptionNestedException + +eh10: stdRET ExceptionHandler + +stdENDP ExceptionHandler + + page + subttl "Local Unwind Handler" +;++ +; +; EXCEPTION_DISPOSITION +; UnwindHandler ( +; IN PEXCEPTION_RECORD ExceptionRecord, +; IN PVOID EstablisherFrame, +; IN OUT PCONTEXT ContextRecord, +; IN OUT PVOID DispatcherContext +; ) +; +; Routine Description: +; +; This function is called when a collided unwind occurs. Its function +; is to retrieve the establisher frame pointer and handler address from +; its establisher's call frame, store this information in the dispatcher +; context record, and return a disposition value of nested unwind. +; +; Arguments: +; +; ExceptionRecord (esp+4) - Supplies a pointer to an exception record. +; +; EstablisherFrame (esp+8) - Supplies the frame pointer of the establisher +; of this exception handler. +; +; ContextRecord (esp+12) - Supplies a pointer to a context record. +; +; DispatcherContext (esp+16) - Supplies a pointer to the dispatcher context +; record. +; +; Return Value: +; +; A disposition value ExceptionCollidedUnwind is returned if an unwind is +; in progress. Otherwise a value of ExceptionContinueSearch is returned. +; +;-- + +stdPROC UnwindHandler,4 + + mov ecx,dword ptr [esp+4] ; (ecx) -> ExceptionRecord + test dword ptr [ecx.ErExceptionFlags],Unwind + mov eax,ExceptionContinueSearch ; Assume NOT unwind + jz uh10 ; not unwind, go return + + +; +; Unwind is in progress - return collided unwind disposition. +; + + mov ecx,[esp+8] ; (ecx) -> EstablisherFrame + mov edx,[esp+16] ; (edx) -> DispatcherContext + mov eax,[ecx+8] ; (eax) -> EstablisherFrame for the + ; handler active when we + ; nested. + mov [edx],eax ; Set DispatcherContext field. + mov eax,ExceptionCollidedUnwind + +uh10: stdRET UnwindHandler + +stdENDP UnwindHandler + + page + subttl "Unlink Exception Registration Record & Handler" +;++ +; +; VOID +; RtlpUnlinkHandler(PEXCEPTION_REGISTRATION_RECORD UnlinkPointer) +; +; Routine Description: +; +; This function removes the specified exception registration record +; (and thus the relevent handler) from the exception traversal +; chain. +; +; Arguments: +; +; UnlinkPointer (esp+4) - Address of registration record to unlink. +; +; Return Value: +; +; The caller's return address. +; +;-- + +cPublicProc _RtlpUnlinkHandler ,1 + + mov ecx,dword ptr [esp+4] + mov ecx,[ecx.ErrNext] + mov fs:PcExceptionList,ecx + stdRET _RtlpUnlinkHandler + +stdENDP _RtlpUnlinkHandler + + page + subttl "Capture Context" +;++ +; +; VOID +; RtlCaptureContext (PCONTEXT ContextRecord) +; RtlpCaptureContext (PCONTEXT ContextRecord) +; +; Routine Description: +; +; This fucntion fills in the specified context record with the +; current state of the machine, except that the values of EBP +; and ESP are computed to be those of the caller's caller. +; +; N.B. This function assumes it is called from a 'C' procedure with +; the old ebp at [ebp], the return address at [ebp+4], and +; old esp = ebp + 8. +; +; Certain 'C' optimizations may cause this to not be true. +; +; N.B. This function does NOT adjust ESP to pop the arguments off +; the caller's stack. In other words, it provides a __cdecl ESP, +; NOT a __stdcall ESP. This is mainly because we can't figure +; out how many arguments the caller takes. +; +; N.B. Floating point state is NOT captured. +; +; RtlpCaptureContext does not capture volitales. +; RtlCaptureContext captures volitales. +; +; Arguments: +; +; ContextRecord (esp+4) - Address of context record to fill in. +; +; Return Value: +; +; The caller's return address. +; +;-- + +cPublicProc _RtlCaptureContext ,1 + + push ebx + mov ebx,[esp+8] ; (ebx) -> ContextRecord + + mov dword ptr [ebx.CsEax],eax + mov dword ptr [ebx.CsEcx],ecx + mov dword ptr [ebx.CsEdx],edx + mov eax, [esp] + mov dword ptr [ebx.CsEbx],eax + + mov dword ptr [ebx.CsEsi],esi + mov dword ptr [ebx.CsEdi],edi + jmp RtlpCaptureCommon +stdENDP _RtlCaptureContext + +cPublicProc _RtlpCaptureContext ,1 + + push ebx + mov ebx,[esp+8] ; (ebx) -> ContextRecord + + mov dword ptr [ebx.CsEax],0 + mov dword ptr [ebx.CsEcx],0 + mov dword ptr [ebx.CsEdx],0 + mov dword ptr [ebx.CsEbx],0 + + mov dword ptr [ebx.CsEsi],0 + mov dword ptr [ebx.CsEdi],0 + +RtlpCaptureCommon: + mov [ebx.CsSegCs],cs + mov [ebx.CsSegDs],ds + mov [ebx.CsSegEs],es + mov [ebx.CsSegFs],fs + mov [ebx.CsSegGs],gs + mov [ebx.CsSegSs],ss + + pushfd + pop [ebx.CsEflags] + + mov eax,[ebp+4] + mov [ebx.CsEip],eax + + mov eax,[ebp] + mov [ebx.CsEbp],eax + + lea eax,[ebp+8] + mov [ebx.CsEsp],eax + + pop ebx + stdRET _RtlpCaptureContext + +stdENDP _RtlpCaptureContext + + page + subttl "Capture Context (private)" +;++ +; +; VOID +; RtlCaptureContext (PCONTEXT ContextRecord) +; +; Routine Description: +; +; This function is similiar too RtlpCaptureContext expect that +; volitales are captured as well. +; +; This fucntion fills in the specified context record with the +; current state of the machine, except that the values of EBP +; and ESP are computed to be those of the caller's caller. +; +; N.B. This function does NOT adjust ESP to pop the arguments off +; the caller's stack. In other words, it provides a __cdecl ESP, +; NOT a __stdcall ESP. This is mainly because we can't figure +; out how many arguments the caller takes. +; +; N.B. Floating point state is NOT captured. +; +; Arguments: +; +; ContextRecord (esp+4) - Address of context record to fill in. +; +; Return Value: +; +; The caller's return address. +; +;-- + + +ifndef WX86_i386 + page + subttl "Get Stack Limits" +;++ +; +; VOID +; RtlpGetStackLimits ( +; OUT PULONG LowLimit, +; OUT PULONG HighLimit +; ) +; +; Routine Description: +; +; This function returns the current stack limits based on the current +; processor mode. +; +; On the 386 we always store the stack limits in the PCR, and address +; both PCR and TEB the same way, so this code is mode independent. +; +; Arguments: +; +; LowLimit (esp+4) - Supplies a pointer to a variable that is to receive +; the low limit of the stack. +; +; HighLimit (esp+8) - Supplies a pointer to a variable that is to receive +; the high limit of the stack. +; +; Return Value: +; +; None. +; +;-- + +cPublicProc _RtlpGetStackLimits ,2 +;cPublicFpo 2,0 + + mov eax,fs:PcStackLimit + mov ecx,[esp+4] + mov [ecx],eax ; Save low limit + + mov eax,fs:PcInitialStack + mov ecx,[esp+8] + mov [ecx],eax ; Save high limit + + stdRET _RtlpGetStackLimits + +stdENDP _RtlpGetStackLimits + +endif + page + subttl "Get Exception Registration List Head" +;++ +; +; PVOID +; RtlpGetRegistrationHead() +; +; Routine Description: +; +; This function returns the address of the first Exception +; registration record for the current context. +; +; Arguments: +; +; None. +; +; Return Value: +; +; The address of the first registration record. +; +;-- + +cPublicProc _RtlpGetRegistrationHead ,0 +;cPublicFpo 0,0 + + mov eax,fs:PcExceptionList + stdRET _RtlpGetRegistrationHead + +stdENDP _RtlpGetRegistrationHead + + page + subttl "Get Return Address" +;++ +; +; PVOID +; RtlpGetReturnAddress() +; +; Routine Description: +; +; This function returns the caller's return address. It assumes +; that a standard 'C' entry sequence has been used, be warned +; that certain optimizations might invalidate that assumption. +; +; Arguments: +; +; None. +; +; Return Value: +; +; The address of the first registration record. +; +;-- + +cPublicProc _RtlpGetReturnAddress ,0 +;cPublicFpo 0,0 + + mov eax,[ebp+4] + stdRET _RtlpGetReturnAddress + +stdENDP _RtlpGetReturnAddress +_TEXT$01 ends + end |