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struct REGPACK
{
unsigned r_ax, r_bx, r_cx, r_dx;
unsigned r_bp, r_si, r_di, r_ds, r_es, r_flags;
};
/* DANGER DANGER -- Self modifying code! */
#asm
.text
save_sp:
dw 0
#endasm
intr(intr, regs)
int intr;
struct REGPACK * regs;
{
#asm
mov bx,sp
push bp
push si
push di
push es
push ds
mov ax,[bx+2]
seg cs
mov [intr_inst+1],al
seg cs
mov [save_sp],sp
mov bx,[bx+4]
mov ah,[bx+18] ! Flags low byte
sahf
mov ax,[bx]
push [bx+2]
mov cx,[bx+4]
mov dx,[bx+6]
mov bp,[bx+8]
mov si,[bx+10]
mov di,[bx+12]
mov es,[bx+16]
mov ds,[bx+14]
pop bx
intr_inst:
int $FF ! Must be a real int .. consider protected mode.
seg cs ! Could be SS as DS==SS
mov sp,[save_sp]
seg cs
mov [save_sp],ds
pop ds
push [save_sp]
push bx
mov bx,sp
mov bx,[bx+12]
mov [bx],ax
pop [bx+2]
mov [bx+4],cx
mov [bx+6],dx
mov [bx+8],bp
mov [bx+10],si
mov [bx+12],di
pop [bx+14]
mov [bx+16],es
pushf
pop [bx+18]
pop es
pop di
pop si
pop bp
#endasm
}
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