/* ----------------------------------------------------------------------------

	CallMyVDEF  -  This is a special glue routine for VDM/VDEF interfacing.
	It exists to allow a Pascal function to call a routine to which it has
	a handle that is inside a global structure.
	
	
	This function expects to be called like:
	
		status := CallMyVDEF (VDEFEntry, VDHandle, message, p1, p2, p3, p4);
		
	per the Video Digitizer Manager spec, returning OSERR.
		

	This routine simply gets the address of the VDEF entry point off the stack,
	cleans up the stack for the VDEF and jumps to the VDEF.
	
	
	
	Copyright ©, 1990-1995, Perceptics Corporation.
	
	
	Module History:
	
		05-July-1990  -  P Whalen
						 Created module.
						 
		27-July-1995  -  P Whalen
						 Added PowerPC native mode option.
						 
						 
 ------------------------------------------------------------------------------*/
 
#include <Types.h>
#include <MixedMode.h>


#ifdef PPCNative
 
/* C glue code needed by PowerPC native version of NIH Image VDM to call
   VDEFs. CallUniversalProc can't be called
   directly from Pascal because is uses a variable number of arguments.

   uppCallCodeInfo = $00000EE0; { FUNCTION (4 byte param, 2 byte param, 4 byte param): OSErr;
*/

enum {
	uppVDEFEntryProcInfo = kPascalStackBased
		 | RESULT_SIZE(SIZE_CODE(sizeof(OSErr)))
		 | STACK_ROUTINE_PARAMETER(1, SIZE_CODE(sizeof(Handle)))
		 | STACK_ROUTINE_PARAMETER(2, SIZE_CODE(sizeof(short)))
		 | STACK_ROUTINE_PARAMETER(3, SIZE_CODE(sizeof(Handle)))
};

OSErr CallMyVDEF(long VDHandle, short message, long parmsPtr, UniversalProcPtr VDEFEntry);



OSErr CallMyVDEF(long VDHandle, short message, long parmsPtr, UniversalProcPtr VDEFEntry)
{
	CallUniversalProc(VDEFEntry, uppVDEFEntryProcInfo, VDHandle, message, parmsPtr);
}

#else
 
 #define CallMyVDEF CALLMYVDEF
 
 
 asm OSErr CallMyVDEF (long VDHandle, short message, long parmsPtr, long VDEFEntry);


 asm OSErr CallMyVDEF (long VDHandle, short message, long parmsPtr, long VDEFEntry)
 {
 		//unlk	a6				// undo the automatic stack frame
 		move.l	(sp)+,d0		// get caller's return address
 		move.l	(sp)+,a0		// get VDEFEntry off the stack
 		move.l	d0,-(sp)		// put return address back on stack
 		jmp		(a0)			// go enter the VDEF
 		rts						// dummy to satisfy compiler--will not execute
 }
 
#endif