.386 .MODEL FLAT
PUBLIC _STST ; Store Status
PUBLIC _LDST ; Load Status
;PUBLIC _ASKY
PUBLIC _MD
PUBLIC _MM
.CODE
_STST PROC NEAR32
; Entry Code ) ------------------------------------
PUSH EBP ; establish stack frame
MOV EBP,ESP
; -------------------------------------------------
; PUSH EFL
pushfd
; Trap Flag set 임의 제거
mov eax, [ebp-4]
and eax, 0FFFFFEFFh
mov [ebp-4], eax
; &context 위치 가리킴
mov esp, [ebp+8]
; EAX 로 이동
add esp, 40
pushad
; EIP(return Address) 대입
push [ebp+4]
; EFL 대입
push [ebp-4]
; esp 위치 조정
add esp, 24
mov eax, ebp
add eax, 8
push eax
push [ebp]
; Exit Code ) ------------------------------------
MOV ESP,EBP ; restore ESP if local variables used
POP EBP ; restore EBP
RET ; return
; ------------------------------------------------
; Store Status
_STST ENDP
; Load Status
_LDST PROC NEAR32
MOV ESP, [ESP+4] ; CONTEXT 주소로 ESP를 옮김 , ESP = &CONTEXT
POPFD ; EFL 을 CPU 로 , EFL = CONTEXT.EFL
POP EAX ; EIP 백업 (EAX Reg 에다가) , EAX = Old EIP
MOV EBX, ESP ; EBX 에 ESP 를 백업 , Current ESP Backup
MOV ESP, [ESP+12] ; 뽑아왔던 ESP 넣음 , ESP = Old ESP
PUSH EAX ; Old EIP 넣음 , SAVE Old EIP
MOV ESP, EBX ; ESP = Current ESP
POPAD ; PUSHAD 와 반대순서로 CPU에 올라가고, ESP는 무시
MOV ESP, [ESP-20] ; ESP를 Return Address 로 돌려주기
SUB ESP, 4
RET ; return
_LDST ENDP
; 반환값 넣는 방법
;_ASKY PROC NEAR32
; Entry Code ) ------------------------------------
; PUSH EBP ; establish stack frame
; MOV EBP,ESP
; -------------------------------------------------
; MOV EAX, 100 ; 반환값은 EAX에
; Exit Code ) -------------------------------------
; MOV ESP,EBP ; restore ESP if local variables used
; POP EBP ; restore EBP
; RET ; return
; -------------------------------------------------
;_ASKY ENDP
_MD PROC NEAR32
; Entry Code ) ------------------------------------
PUSH EBP ; establish stack frame
MOV EBP,ESP
; -------------------------------------------------
MOV EAX, [EBP+8] ; EAX = &A
MOV EAX, [EAX] ; EAX = *(&A)
; Exit Code ) -------------------------------------
MOV ESP,EBP ; restore ESP if local variables used
POP EBP ; restore EBP
RET ; return
; -------------------------------------------------
_MD ENDP
_MM PROC NEAR32
; Entry Code ) ------------------------------------
PUSH EBP ; establish stack frame
MOV EBP,ESP
; -------------------------------------------------
PUSH EBX ; EBX Back up
MOV EAX, [EBP+8] ; EAX = &A
MOV BL, [EBP+12] ; BL = 0xFF
MOV [EAX], BL ; *(&A) = 0xFF
POP EBX
; Exit Code ) -------------------------------------
MOV ESP,EBP ; restore ESP if local variables used
POP EBP ; restore EBP
RET ; return
; -------------------------------------------------
_MM ENDP
END
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