* HandlerInterface()
* from RKM Vol I, Pg 3-113 for use with ADD_HANDLER example program
* original code allowed C function as input handler
* too slow, so new code rewrites it in ASM
* Sean Riddle
* OKC ACE BBS (405) 631-9040
* let's see, InputEvent pointer in A0....

   CSECT HandlerInterface

*  XREF _myhandler               ; don't need, since not used
   XDEF _HandlerInterface

_HandlerInterface:

*           MOVE.L   A1,-(A7)    ; old code: push data area
*           MOVE.L   A0,-(A7)    ; and InputEvent pointer onto stack,
*           JSR      _myhandler  ; call C function
*           ADDQ     #8,A7       ; fix stack, then exit (RTS)

            CMPI.B   #2,4(A0)    ;  IS THIS A RAWMOUSE EVENT?
            BNE      OUTTAHERE   ;  NOPE, LET'S LEAVE IT ALONE
            NEG.W    10(A0)      ;  MAKE OPPOSITE X DIRECTION
            NEG.W    12(A0)      ;  MAKE OPPOSITE Y DIRECTION
            CMPI.W   #$68,6(A0)  ;  LBUTTON DOWN?
            BNE      NOTLBUT     ;  NOPE, TRY RBUTTON
            MOVE.W   #$69,6(A0)  ;  YES, MAKE IT RBUTTON
            BRA      BUTUP       ;  SKIP NEXT TEST (ALWAYS PASSES, HMMM)
NOTLBUT     CMPI.W   #$69,6(A0)  ;  RBUTTON DOWN?
            BNE      BUTUP       ;  NO, TRY LBUTTON UP
            MOVE.W   #$68,6(A0)  ;  YES, MAKE IT LBUTTON
BUTUP       CMPI.W   #$E8,6(A0)  ;  HAS LBUTTON BEEN RELEASED?
            BNE      LBNOTUP     ;  NAH, TEST RBUTTON
            MOVE.W   #$E9,6(A0)  ;  YUP, MAKE IT RBUTTON UP
            BRA      OUTTAHERE   ;  LET'S GO
LBNOTUP     CMPI.W   #$E9,6(A0)  ;  HAS RBUTTON BEEN RELEASED?
            BNE      OUTTAHERE   ;  NOPE, TIME TO EXIT
            MOVE.W   #$E8,6(A0)  ;  YES, NOW IT'S A LBUTTON UP
OUTTAHERE   MOVE.L   A0,D0       ;  EXIT LIKE C WOULD - PTR IN D0
            RTS

   END