Fortran Printing Interface

By Jay Lieske, La Canada, CA

In Absoft FORTRAN version 2.3 one usually must employ Absoft’s special routine called PrPort.sub in order to use the Printing Manager on the Macintosh. PrPort.sub employs the old RAM-based printing manager, but recent trends suggest that it would be better to use the printing traps accessible through “_PrGlue” at $A8FD since these routines are now in ROM and contain special routines such as PrGeneral that are unavailable in the RAM-based printing manager. In addition, PrPort.sub, which is written in assembly language, is limited to the hard-coded routines which existed at the time Absoft developed the routine and is thus not extendible. Since usage of PrPort.sub will undoubtedly limit the development of FORTRAN programs on the Macintosh, it is of interest to see how one might use Absoft’s Toolbx.sub in order to implement the new ROM-based printing manager traps.

The Toolbx.sub routine from Absoft employs an encoded ‘trap dispatch’ LongInt to describe the toolbox or OS trap number, as well as to describe the parameters required for the toolbox or OS calls. The new printing traps accessible through the _PrGlue trap at $A8FD require that a special ‘routine selector’ be pushed onto the stack prior to the $A8FD trap instruction. Hence, if we are to succeed in using the print traps, we must be able to insert this routine selector number onto the stack.

By studying and disassembling Absoft’s Toolbx.sub it was found that the routine selector parameter could be put into the Toolbx.sub call as the final parameter (i.e. the parameter just before the final closing parenthesis) and that it would be pushed onto the stack just before Toolbx.sub executed the trap number. In order to instruct Toolbx.sub that there was another parameter for it to pass, however, the ‘trap dispatch’ code had to be modified. That is where the disassembly of Toolbx.sub became important because current Absoft documentation is not always correct on this matter.

We have developed the include files ‘prtrap.inc’ and ‘PrGenDefs.inc’ which can be used with Absoft Fortran’s Toolbx.sub in order to implement the print traps. A similar method could be employed for any other new traps (or traps and additional routine selectors’) that Apple develops. The file ‘prtrap.inc’ contains the encoded trap dispatch number and the routine selector for all the new print traps documented in Inside Macintosh Volume V. The routine selector for PrGeneral, which inadvertently was left out of Inside Mac, was found in Lightspeed Pascal’s equates as $70070480. We also include a file ‘PrGenDefs.inc’ which contains the equates required for use of the PrGeneral gateway, potentially a very useful new trap which enables one to check and to set the resolution of the printer in use.

To demonstrate how the Toolbx.sub traps are implemented in a program, first consider the Pascal calling-sequences as documented in Inside Mac. Suppose that a trap ‘PrRoutine’ is documented by Apple as being implemented like this in Pascal:

     PrRoutine(Arg1, Arg2,...,Argn);

then the Toolbx.sub routine in Fortran would be employed as follows:

      call Toolbx( PrRoutineCode, Arg1, Arg2,...,Argn, xPrRoutineCode) 

if the toolbox trap is a procedure. If the toolbox call is a function then the Pascal version would be

   Result := PrRoutine(Arg1, Arg2,...,Argn);

while the Toolbx.sub Fortran version would be

  Result = Toolbx(PrRoutine,Arg1, Arg2,...,Argn,xPrRoutine).

The analogous calls using prport.sub for a subroutine would be: call PrPort(Code, Arg1, Arg2,..., Argn). Programs which currently employ PrPort could readily be changed simply by replacing PrPort with Toolbx and appending the ‘xPrRoutine’ parameter.

An example program ‘demotrap.for’ is included for implementing the new print manager trap-based calls. The program does not actually do any printing, but shows how one can access the print record and query the printer for variable resolutions. Just use the Chooser to select your ‘printer’ and then the usual dialogs will come up on screen to demonstrate that everything works as advertised. A colleague has employed these new traps in a large plotting package which was ported over to the Mac from a mainframe computer and the results are quite satisfactory.

Listing One: Demonstration Program
      program demotrap
C     See if can use ‘Printer traps’ via $A8FD PrGlue and TOOLBX.sub
C  A simple sample program demonstrating its capability for Absoft Fortran 
2.3.
C  This program does not actually do any printing.
C  J. Lieske 12/87

C * * * * * * * * * *
* FUNCTION PTR (ANYTYPE) : PTR;                ; A ‘funny’ trap.
      INTEGER PTR                            ! from Absoft’s MISC.inc
      PARAMETER (PTR=Z’C0000000')

      integer NEWHANDLE
! from Absoft’s MEMORY.inc
      parameter (NEWHANDLE=Z’122000A8')
      integer iPrintSize
! The Print record size.[120 bytes]
      parameter (iPrintSize=120)
! from Absoft’s PRDEFS.inc
C * * * * * * * * * *
C   GRXMX0 : default x size (pixels).  These will be taken from the print 
record
C   GRYMX0 : default y size (pixels)
C   GRXPIN : pixels per inch in x
C   GRYPIN : pixels per inch in y
      REAL  GRXPIN, GRYPIN
      INTEGER   GRXMX0, GRYMX0
      INTEGER*4 TOOLBX 
! MAC TOOLBOX INTERFACE

x     integer*4 debugger
! just in case you want to use MacsBug
x     parameter (debugger=z’9FF00000')
x     call toolbx(debugger)
! put the call where it’s needed
*
* INITIALIZE THE PRINT RECORD FOR THE MACINTOSH
*
      integer*2 iversion
      integer*2 ernum

* PRINT MANAGER FUNCTION DEFINITIONS for toolbox-based traps
      include prtrap.inc
      include PrGenDefs.inc

      INTEGER PRRECHDL
             ! HANDLE TO THE PRINT RECORD.
      INTEGER POINT
             ! DEREFERENCED HANDLE
      LOGICAL OK

      write(*,*) ‘This program demonstrates printer traps in Fortran.’
      write(*,*) ‘It won’’t actually print anything, but shows how to’
      write(*,*) ‘access the printer traps in Absoft Fortran.’  
      write(*,*) ‘It will write the data out to ‘’output.fil’’’
      write(*,*) ‘so you can read it.’

      call toolbx(propen, xpropen)  ! PrOpen

      PRRECHDL = TOOLBX(NEWHANDLE, IPRINTSIZE)  ! GET A PRINT RECORD 
HANDLE.
      call toolbx(printdefault,PRRECHDL,xprintdefault)      ! get defaults

C  get printer version number
      iversion = toolbx(prdrvrvers, xprdrvrvers )
      write (*,*) ‘iversion = ‘, iversion
      open(15,file=’output.fil’, status=’NEW’)
      write (15,*) ‘iversion = ‘, iversion

C  see if PrGeneral will work
      gOpCode = 4       ! set iOpCode
C--use PTR to get address of data record
      pGetRslData = toolbx(PTR,GetRslDataRec)
      call toolbx(PrGeneral, pGetRslData, xPrGeneral)
C  should now check for PrError also
      ernum = toolbx(PrError, xPrError)
      write(*,*) ‘PrError number = ‘, ernum
      write(15,*) ‘PrError number = ‘, ernum

      write(*,*) ‘Interpreted record’
      write(*,*) ‘iOpCode= ‘,gOpCode
      write(*,*) ‘iError= ‘,gError
      write(*,*) ‘lReserved= ‘,gReserved
      write(*,*) ‘iRgType= ‘,iRgType
      write(*,*) ‘XRslRg= ‘,XRslRg
      write(*,*) ‘YRslRg= ‘,YRslRg
      write(*,*) ‘iRslRecCnt= ‘,iRslRecCnt
      write(*,*) ‘rgRslRec= ‘,((rgRslRec(i,j), i=1,2), j=1,iRslRecCnt)

      write(15,*) ‘Interpreted record’
      write(15,*) ‘iOpCode= ‘,gOpCode
      write(15,*) ‘iError= ‘,gError
      write(15,*) ‘lReserved= ‘,gReserved
      write(15,*) ‘iRgType= ‘,iRgType
      write(15,*) ‘XRslRg= ‘,XRslRg
      write(15,*) ‘YRslRg= ‘,YRslRg
      write(15,*) ‘iRslRecCnt= ‘,iRslRecCnt
      write(15,*) ‘rgRslRec= ‘,((rgRslRec(i,j), i=1,2), j=1,iRslRecCnt)

C now try to set it to 300 dpi
      pOpCode = 5       ! set iOpCode for SetRsl
      hPrint = PRRECHDL ! handle to print record
      iXRsl = 300
      iYRsl = 300
      pSetRsl = toolbx(PTR,SetRslRec)
      call toolbx(PrGeneral, pSetRsl, xPrGeneral)

      OK = toolbx(prstldialog,PRRECHDL,xprstldialog)  ! std dialog

      OK=toolbx(prjobdialog,PRRECHDL,xprjobdialog)    ! PrJobDialog
      if (.not. OK) STOP
*     NOW READ PLOT DIMENSION VALUES WITH THOSE FROM THE PRINTER INFO 
RECORD.
*     PRRECHDL IS A HANDLE TO THE PRINTER RECORD WHICH IS 120 BYTES
*     THE VALUES WE CARE ABOUT ARE THE VERTICAL AND HORIZONTAL RESOLUTION
*     AND THE PAGE RECTANGLE WHICH ARE AT OFFSETS 4,6, AND 8 INTO THE 
RECORD

      POINT=LONG(PRRECHDL)
      GRXMX0 = WORD(POINT+14)
      GRYMX0 = WORD(POINT+12)
      GRXPIN = FLOAT(WORD(POINT+6))
      GRYPIN = FLOAT(WORD(POINT+4))
      write(*,*)  ‘resolutions’, GRXMX0,GRYMX0,GRXPIN,GRYPIN
      write(15,*)  ‘resolutions’,GRXMX0,GRYMX0,GRXPIN,GRYPIN
      close(15)


*
*     CLOSE UP THE PRINTER
*
      call toolbx(prclose,xprclose)       ! Close the printing grafport

      pause ‘Press return to exit’
      stop
      end
Listing Two: PrTrap.inc
* File: prtrap.inc      29 Dec 1987       JHL
*     A replacement for Absoft’s prport.inc and prport.sub .
*     This implements traps for Fortran so that it can be used with toolbx.sub 
.
*     Called together by J. Lieske, Jet Propulsion Laboratory, based 
upon
*     Inside Mac V and Lightspeed Pascal equates.
*
*     The general calling sequence for procedures is
*           CALL TOOLBX(PrRoutine, Args, xPrRoutine)
*     while that for a function is 
*           TOOLBX(PrRoutine, Args, xPrRoutine) .
*     In the above parameters, PrRoutine is the encoded PrGlue (Printer 
Trap
*     $A8FD) parameter and xPrRoutine is the ‘call number’ as specified 
in
*     Inside Mac V Chapter 22.  The ‘Args’ are the sequence of arguments 
to
*     the procedure or function as specified by Inside Mac.  
*           Basically, the xPrRoutine ‘call number’ is placed on the 
stack
*     just ahead of the printer trap number ($A8FD) and the Fortran PrRoutine
*     parameter tells Fortran’s TOOLBX how to interpret the ‘Args’ and
*     ‘xPrRoutine’ values.
*           For example, the routine PrintDefault is called from 
*     Fortran as follows:  CALL TOOLBX( PRINTDEFAULT, hPrint, xPRINTDEFAULT) 
.
*
* * * * * * * * * * * * * * * * * * * * *
*     Modification history:
*     12/87 JHL   Developed basic parameters from Absoft’s documentation
*                 of toolbx.sub and Apple’s Inside Mac V and Lightspeed
*                 Pascal.
* * * * * * * * * * * * * * * * * * * * *
* PROCEDURE PrOpen; 
      INTEGER*4 PROPEN, xPROPEN
      PARAMETER (PROPEN=Z’8FD10000', xPROPEN=Z’C8000000')

* PROCEDURE PrClose; 
      INTEGER*4 PRCLOSE, xPRCLOSE
      PARAMETER (PRCLOSE=Z’8FD10000', xPRCLOSE=Z’D0000000')

* PROCEDURE PrintDefault (hPrint: THPrint);
      INTEGER*4 PRINTDEFAULT, xPRINTDEFAULT
      PARAMETER (PRINTDEFAULT=Z’8FD12000', xPRINTDEFAULT=Z’20040480')

* FUNCTION PrValidate (hPrint: THPrint) : BOOLEAN;
      INTEGER*4 PRVALIDATE, xPRVALIDATE
      PARAMETER (PRVALIDATE=Z’8FDD2000', xPRVALIDATE=Z’52040498')

* FUNCTION PrStlDialog (hPrint: THPrint) : BOOLEAN;
      INTEGER*4 PRSTLDIALOG, xPRSTLDIALOG
      PARAMETER (PRSTLDIALOG=Z’8FDD2000', xPRSTLDIALOG=Z’2A040484')

* FUNCTION PrJobDialog (hPrint: THPrint) : BOOLEAN;
      INTEGER*4 PRJOBDIALOG, xPRJOBDIALOG
      PARAMETER (PRJOBDIALOG=Z’8FDD2000', xPRJOBDIALOG=Z’32040488')

* PROCEDURE PrJobMerge (hPrintSrc, hPrintDst: THPrint);
      INTEGER*4 PRJOBMERGE, xPRJOBMERGE
      PARAMETER (PRJOBMERGE=Z’8FD12400', xPRJOBMERGE=Z’5804089C’)

* FUNCTION PrOpenDoc (hPrint: THPrint; pPrPort: TPPrPort;
*                 pIOBuf: Ptr) : TpPrPort;
      INTEGER*4 PROPENDOC, xPROPENDOC
      PARAMETER (PROPENDOC=Z’8FD92480', xPROPENDOC=Z’04000C00')

* PROCEDURE PrCloseDoc (pPrPort: TPPrPort);
      INTEGER*4 PRCLOSEDOC, xPRCLOSEDOC
      PARAMETER (PRCLOSEDOC=Z’8FD12000', xPRCLOSEDOC=Z’08000484')

* PROCEDURE PrOpenPage (pPrPort: TPPrPort; pPageFrame: TPRect);
      INTEGER PROPENPAGE, xPROPENPAGE
      PARAMETER (PROPENPAGE=Z’8FD12400', xPROPENPAGE=Z’10000808')

* PROCEDURE PrClosePage (pPrPort: TPPrPort);
      INTEGER*4 PRCLOSEPAGE, xPRCLOSEPAGE
      PARAMETER (PRCLOSEPAGE=Z’8FD12000', xPRCLOSEPAGE=Z’1800040C’)


* Note: prStatus should actually be passed as a pointer to a TPrStatus
*     record.
* PROCEDURE PrPicFile (hPrint: THPrint; pPrPort: TPPrPort; pIOBuf: Ptr;
*                 pDevBuf: Ptr; VAR prStatus: TPrStatus);
      INTEGER*4 PRPICFILE, xPRPICFILE
      PARAMETER (PRPICFILE=Z’8FD124B2', xPRPICFILE=Z’60051480')

* FUNCTION PrError : INTEGER;
      INTEGER*4 PRERROR, xPRERROR
      PARAMETER (PRERROR=Z’8FD50000', xPRERROR=Z’BA000000')

* PROCEDURE PrSetError(iErr : INTEGER);
      INTEGER*4 PRSETERROR, xPRSETERROR
      PARAMETER (PRSETERROR=Z’8FD0A000', xPRSETERROR=Z’C0000200')

* PROCEDURE PrDrvrOpen;
      INTEGER*4 PRDRVROPEN, xPRDRVROPEN
      PARAMETER (PRDRVROPEN=Z’8FD10000', xPRDRVROPEN=Z’80000000')

* PROCEDURE PrDrvrClose;
      INTEGER*4 PRDRVRCLOSE, xPRDRVRCLOSE
      PARAMETER (PRDRVRCLOSE=Z’8FD10000', xPRDRVRCLOSE=Z’88000000')

* PROCEDURE PrCtlCall(iWhichCtl: Integer; lParam1, lparam2, lparam3: 
LongInt);
      INTEGER*4 PRCTLCALL, xPRCTLCALL
      PARAMETER (PRCTLCALL=Z’8FD0A490', xPRCTLCALL=Z’A0000E00')

* FUNCTION PrDrvrDCE: Handle;
      INTEGER*4 PRDRVRDCE, xPRDRVRDCE
      PARAMETER (PRDRVRDCE=Z’8FD90000', xPRDRVRDCE=Z’94000000')

* FUNCTION PrDrvrVers: Integer;
      INTEGER*4 PRDRVRVERS, xPRDRVRVERS
      PARAMETER (PRDRVRVERS=Z’8FD50000', xPRDRVRVERS=Z’9A000000')

* PROCEDURE PrGeneral(pData: Ptr);
      INTEGER*4 PRGENERAL, xPRGENERAL
      PARAMETER (PRGENERAL=Z’8FD12000', xPRGENERAL=Z’70070480')
* PrGeneral is the gateway to the calls documented in Inside Mac V
* concerning added capabilities for printer resolution, etc.
* See the file PrGenDefs.inc and the demo program for usage

* PROCEDURE PrPurge;
      INTEGER*4 PRPURGE, xPRPURGE
      PARAMETER (PRPURGE=Z’8FD10000', xPRPURGE=Z’A8000000')

* PROCEDURE PrNoPurge;
      INTEGER*4 PRNOPURGE, xPRNOPURGE
      PARAMETER (PRNOPURGE=Z’8FD10000', xPRNOPURGE=Z’B0000000')

* FUNCTION PrStlInit (hPrint: THPrint): TPPrDlg;
      INTEGER*4 PRSTLINIT, xPRSTLINIT
      PARAMETER (PRSTLINIT=Z’8FD92000', xPRSTLINIT=Z’3C04040C’)

* FUNCTION PrJobInit (hPrint: THPrint): TPPrDlg;
      INTEGER*4 PRJOBINIT, xPRJOBINIT
      PARAMETER (PRJOBINIT=Z’8FD92000', xPRJOBINIT=Z’44040410')

* FUNCTION PrDlgMain(hPrint: THPrint; pDlgInit: ProcPtr): Boolean;
      INTEGER*4 PRDLGMAIN, xPRDLGMAIN
      PARAMETER (PRDLGMAIN=Z’8FDD2400', xPRDLGMAIN=Z’4A040894')

* end of prtrap.inc listing
Listing Three: PrGenDefs.inc
* File: PrGenDefs.inc   Definitions for calls to printer trap PrGeneral
*  1/11/88  Jay Lieske
*
* Information for GetRsl
*     This file contains definitions for calls to PrGeneral with iOpCode=4
*     (called gOpCode here) which is the GetRslData call.
*

* the GetRslData record is of length 128 bytes

      integer*1   GetRslDataRec(128)
      integer*2   gOpCode
      integer*2   gError
      integer*4   gReserved
      integer*2   iRgType
      integer*2   XRslRg(2)
      integer*2   YRslRg(2)
      integer*2   iRslRecCnt
      integer*2   rgRslRec(2,27)
                              ! defined as ARRAY[1..27] of TRslRec
      equivalence (GetRslDataRec(1), gOpCode)
      equivalence (GetRslDataRec(3), gError)
      equivalence (GetRslDataRec(5), gReserved)
      equivalence (GetRslDataRec(9), iRgType)
      equivalence (GetRslDataRec(11), XRslRg)
      equivalence (GetRslDataRec(15), YRslRg)
      equivalence (GetRslDataRec(19), iRslRecCnt)
      equivalence (GetRslDataRec(21), rgRslRec)

      integer*4 pGetRslData
C     parameter (gOpCode = 4)

* You must set the value of gOpCode
* in program. Get pointer to GetRslDataRec via: pGetRslData = TOOLBX(PTR,GetRslDataRec 
)
* and then CALL toolbx(PrGeneral, pGetRslData, xPrGeneral)

* end of data for GetRsl

* Information for SetRsl
*     This file contains definitions for calls to PrGeneral with iOpCode=5
*     (called pOpCode here) which is the SetRslData call.
*

* the SetRslData record is of length 16 bytes

      integer*1   SetRslRec(16)
      integer*2   pOpCode
      integer*2   pError
      integer*4   pReserved
      integer*4   hPrint
      integer*2   iXRsl
      integer*2   iYRsl

      equivalence (SetRslRec(1), pOpCode)
      equivalence (SetRslRec(3), pError)
      equivalence (SetRslRec(5), pReserved)
      equivalence (SetRslRec(9), hPrint)
      equivalence (SetRslRec(13), iXRsl)
      equivalence (SetRslRec(15), iYRsl)

      integer*4 pSetRsl
C     parameter (pOpCode = 5)

*  You must set the values of pOpCode = 5 and hPrint = handle to Print 
Record
* in program. Get pointer to SetRslRec via: pSetRsl = TOOLBX(PTR,SetRslRec)
* and then CALL toolbx(PrGeneral, pSetRsl, xPrGeneral)
* end of data forSetRsl
* end of file PrGenDefs.inc