篩選器異常處理

.386
.model flat,stdcall
option casemap:none
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;include
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include windows.inc
include user32.inc
includelib user32.lib
include kernel32.inc
includelib kernel32.lib
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;數據段
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.data
lpOldHandler dd ?
.const
szMsg db "異常發生位置:%08X，%08X，異常代碼:%08X，標誌：%08X",0
szSafe db "回到了安全的地方",0
szTitle db "篩選器異常處理的例子",0
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;代碼段
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.code
_Handler proc _lpExceptionPoint
LOCAL @szBuffer[256]:byte
pushad
mov esi,_lpExceptionPoint
assume esi:ptr EXCEPTION_POINTERS
mov edi,[esi].ContextRecord
mov esi,[esi].pExceptionRecord
assume esi:ptr EXCEPTION_RECORD,edi:ptr CONTEXT
mov eax,[esi].ExceptionFlags
;如果標誌被置位，說明異常是致命的，應該退出
and eax,00000001h
.if eax==1
mov eax,EXCEPTION_CONTINUE_SEARCH
ret
.endif
;ExceptionCode中包含了，異常的類型，嚴重性，觸發異常的設置，是內存
;還是網絡，還是CPU，還是接口卡，還是多媒體設置
;ExceptionFlag中指名了異常是否導致程序的終止
invoke wsprintf,addr @szBuffer,addr szMsg,\
[edi].regEip,[esi].ExceptionAddress,[esi].ExceptionCode,[esi].ExceptionFlags
invoke MessageBox,NULL,addr @szBuffer,NULL,MB_OK
mov [edi].regEip,offset _SafePlace
assume esi:nothing,edi:nothing
popad
;返回值，根據ExceptionFlag來決定是否應該讓程序進行下去
mov eax,EXCEPTION_CONTINUE_EXECUTION
ret
_Handler endp


start:
invoke SetUnhandledExceptionFilter,addr _Handler
mov lpOldHandler,eax
xor eax,eax
mov dword ptr [eax],0
_SafePlace:
invoke MessageBox,NULL,addr szSafe,addr szTitle,MB_OK
invoke ExitProcess,NULL
end start