;
;	File:		puDispatch.a
;
;	Contains:	Dispatch code for the picture utilities package.
;
;	Written by:	Dave Good. Some ideas stolen from Konstantin Othmer and Bruce Leak. Prototyped by Cris Rys.
;
;	Copyright:	© 1990, 1992 by Apple Computer, Inc.  All rights reserved.
;
;	Change History (most recent first):
;
;	   <SM2>	 11/5/92	SWC		Changed INCLUDEs to a LOAD of StandardEqu.d.
;		 <6>	 9/21/90	gbm		(Actually DDG) Fixed string problem. Also added code for the Non
;									ProcHelper version to clear out the high byte of the selector
;									(the number of parameters).
;		 <5>	 9/21/90	DDG		Made changes from code review. Changed the dispatch to use proc
;									helper. I also left the old code conditionaled out, so that we
;									can always do test builds if we need to.
;		 <4>	  8/3/90	DDG		Changed the selectors back to the by one scheme.
;		 <3>	 7/31/90	DDG		Fixed the check for the maximum selector to reflect the by-two
;									scheme.
;		 <2>	 7/29/90	DDG		Fixed header.
;		 <1>	 7/29/90	DDG		First checked in using new structure.
;


				MACHINE	MC68000
				CASE	OBJ

				LOAD	'StandardEqu.d'


				STRING	ASIS


;----------------------------------------------------------------------------------------------------

PictUtilEntry	MAIN  EXPORT

				IMPORT	__GETPICTINFO
				IMPORT	__GETPIXMAPINFO
				IMPORT	__NEWPICTINFO
				IMPORT	__RECORDPIXMAPINFO
				IMPORT	__RECORDPICTINFO
				IMPORT	__RETRIEVEPICTINFO
				IMPORT	__DISPOSPICTINFO

	IF  0  THEN

				and.w	#$00FF,d0					; clear the upper byte (number of parameters)
				cmp.w	#6,d0						; if unsigned d0 > max selector,
				bhi.s	exit						; don't do anything
				lsl.w	#2,d0						; multiply our selector by four to get the true jump table offset
				jmp		dispatchTable(d0.w)			; jump in jump table

dispatchTable
				jmp		__GETPICTINFO				; selector  0
				jmp		__GETPIXMAPINFO				; selector  1
				jmp		__NEWPICTINFO				; selector  2
				jmp		__RECORDPICTINFO			; selector  3
				jmp		__RECORDPIXMAPINFO			; selector  4
				jmp		__RETRIEVEPICTINFO			; selector  5
				jmp		__DISPOSPICTINFO			; selector  6

exit			move.l	(sp)+,a0					; get return address
				swap	d0							; get size of parameters in low word
				add.w	d0,sp						; get rid of parameters
				moveq	#paramErr,d0				; return parameter error in D0
				move.w	d0,(sp)						; return parameter error in function result
				jmp		(a0)						; and return to caller

	ELSE

;
;	Macro to build jump table
;
				MACRO
				JT		&entry
				IMPORT	&entry
				dc.w	&entry - MyDispatchTable
				ENDM

;
;	Header for ProcHelper
;

				dc.w	$A9FF						; package entry point (unused now)
				dc.b	'PACK'
				dc.w	15							; package number
				dc.w	1							; version

;
;	DispatchTable for DispatchHelper
;

MyDispatchTable
				dc.w	0							; dispatchFlags (always 0)
				dc.b	$00							; first selector (0 for GetPictInfo)
				dc.b	$06							; last selector  (6 for DisposPictInfo)

				JT		__GETPICTINFO				; selector  0
				JT		__GETPIXMAPINFO				; selector  1
				JT		__NEWPICTINFO				; selector  2
				JT		__RECORDPICTINFO			; selector  3
				JT		__RECORDPIXMAPINFO			; selector  4
				JT		__RETRIEVEPICTINFO			; selector  5
				JT		__DISPOSPICTINFO			; selector  6

	ENDIF

				ENDPROC

;----------------------------------------------------------------------------------------------------

				END