;-------------------------------------------------------------------------
;
; another way how to kill bpms
;
; 
;
;
;-------------------------------------------------------------------------

.586p
.Model Flat

extrn     ExitProcess     : PROC     ;procedure to shut down a process
extrn     MessageBoxA     : PROC     ;procedure to show a MessageBox
extrn     CreateThread    : PROC

.Data                                        
caption   db "DAEMON",0
text      db "try to set a bpm @ MessageBoxA or ExitProcess!",0

thread_id dd ?
syncron_1 dd ?
syncron_2 dd ?

.Code
Main:   push    offset thread_id
        push    0
        push    0
        push    offset second_thread
        push    0
        push    0
        call    CreateThread
        
no_1:   cmp     syncron_1,1
        jnz     no_1

        push    00h
        push    offset caption     
        push    offset text            
        push    00h                     
        call    MessageBoxA      

        mov     syncron_2,1
        jmp     $

second_thread:
        push    edx
        sidt    [esp-2]                         ; Interrupt table to stack
        pop     edx
        add     edx,5*8+4                       ; Get interrupt vector
        mov     ebx,[edx]
        mov     bx,word ptr [edx-4]     

        lea     edi,handler

        mov     [edx-4],di
        ror     edi,16                  
        mov     [edx+2],di

kill_em:int     5
        mov     syncron_1,1
        cmp     syncron_2,1
        jnz     kill_em

        mov     [edx-4],bx
        ror     ebx,16
        mov     [edx+2],bx

        call    ExitProcess

handler:mov     eax,0400h
        mov     dr7,eax         ; store 0x400h in debug register7
        iretd


End Main                        ;End of code, Main is the entrypoint