****************************************************************************
*  Programme : KillRLE.asm                                                 *
*  Usage     : KillRLE                                                     *
*  Version   : V1.00                                                       *
*  Date      : 07.02.1990                                                  *
*  Author    : Jörg Sixt                                                   *
*  Purpose   : Checks and kills "Revenge of the Lamer Exterminator"        *
*  Language  : A68K-Assembler,Blink from Fish 110                          *
*  Bugs      : accept no arguments                                         *
****************************************************************************

             SECTION BEGIN,CODE

EXECBASE:    EQU      $4
OPENLIBRARY: EQU     -$228
CLOSELIBRARY: EQU    -$19E
OUTPUT:      EQU     -$3C
OPEN:        EQU     -$1E
CLOSE:       EQU     -$24
READ:        EQU     -$2A
WRITE:       EQU     -$30
SEEK:        EQU     -$42
DELETEFILE:  EQU     -$48
MODE_READWRITE: EQU    1004
OFFSET_BEGINNING: EQU -$1

OPENLIB:     MACRO
             lea      \1,a1
             moveq    #0,d0
             jsr      OPENLIBRARY(a6)
             move.l   d0,\2
             beq      \3
             ENDM
CLOSELIB:    MACRO
             lea      \1,a1
             jsr      CLOSELIBRARY(a6)
             ENDM
PRINT:       MACRO
             move.l   Outhandle,d1
             move.l   \1,d2
             move.l   \2,d3
             jsr      WRITE(a5)
             ENDM

Begin:       move.l   EXECBASE,a6
             OPENLIB  Dosname,a5,#End
             jsr      OUTPUT(a5)
             move.l   d0,Outhandle
             beq      End

             move.l   #sssName,d1
             move.l   #MODE_READWRITE,d2
             jsr      OPEN(a5)
             move.l   d0,d1
             beq      openError
             move.l   d0,handle
             move.l   #Buffer,d2
             move.l   #5,d3
             jsr      READ(a5)

             lea      RLE,a0
             lea      Buffer,a1
             move.l   #4,d0
CompareLoop: cmpm.b   (a0)+,(a1)+
             bne      sssClose
             dbf.s    d0,CompareLoop

             PRINT    #RLEMess,#101
             move.l   handle,d1
             move.l   #0,d2
             move.l   #OFFSET_BEGINNING,d3
             jsr      SEEK(a5)

             move.l   handle,d1
             move.l   #KillBuf,d2
             move.l   #5,d3
             jsr      WRITE(a5)
             cmp.l    #5,d0
             bne      killError

             move.l   #VirName,d1
             jsr      DELETEFILE(a5)
             tst.l    d0
             beq      killError

sssClose:    move.l   handle,d1
             jsr      CLOSE(a5)

End:         move.l   #0,d0
             rts

openError:   PRINT    #openErrMess,#29
             bra      End
killError:   PRINT    #killErrMess,#18
             bra      sssClose

             SECTION  VARS,BSS
             even
Outhandle:   ds.l     1
handle:      ds.l     1
Buffer:      ds.b     5

             SECTION  CONST,DATA
             even
Dosname:     dc.b     'dos.library',0
sssName:     dc.b     ':s/startup-sequence',0
VirName:     dc.b     ':'
RLE:         dc.b     $A0,$A0,$A0,$A0,$A0,0
RLEMess:     dc.b     'The disk is infected with the "Revenge of the',10
             dc.b     'Lamer Exterminator". I kill him now. Make a reset then',10
KillBuf:     dc.b     $20,$20,$20,$20,$20
openErrMess: dc.b     'Can`t open startup-sequence!',10
killErrMess: dc.b     'Can`t kill virus!',10
             END