gno/sys/fileport/fileport/port.macros

; 
;   Copyright (C) Kopriha Software, 1990 - 1991
;   All rights reserved.
;   Licensed material -- property of Kopriha Software
; 
;   This software is made available solely pursuant to the terms
;   of a Kopriha Software license agreement which governs its use.
;
;
; The following macros (port_routine/port_return) are support
; routines for IIGS port drivers.
;
;
; Macros: port_routine (<length>:<parm name>[,...])[,<work size>]
;          - Enter a port driver routine
;
;         port_return <length>:<return name>[,<completion routine>]
;          - Exit a port driver routine
;          - This macro must be followed by an RTL.  By coding the
;            macro this way you can customize the return (some, but
;            not all port driver routines must return after a CMP #1.
;            See the source to port.asm for the details).
;
;
; Note: These macros are derived from the csubroutine/creturn
;       macros supplied with Orca/C (on the demos disk).
;
 MACRO
&lab port_subroutine &parms,&work
&lab anop                                 Places the label from macro invocation
 aif c:&work,.a                           If there is a work parm goto .a
 lclc &work                               Local define work a string
&work setc 0                              Set work to zero
.a                                     .a
 gbla &totallen                           Global define totallen
 gbla &worklen                            Global define worklen
 gbla &PClen                              Global define length of PC
&worklen seta &work                       Set worklen = work (type conversion)
&totallen seta 0                          Set totallen to zero
&PClen seta 8                             Set PC length to 8 (6(rtnPC*2)+1(direct page)+1(data bank))
 aif c:&parms=0,.e                        If there are no parms to routine then goto .e
 lclc &len                                Local define char len
 lclc &p                                  Local define char p
 lcla &i                                  Local define int i
&i seta 1                                 i = 1
.b                                     .b
&p setc &parms(&i)                        p = parms[i]
&len amid &p,2,1                          len = substr(p,2,1)
 aif "&len"=":",.c                        if len == ':' goto .c
&len amid &p,1,2                          len = substr(p,1,2) {First 2 chars}
&p amid &p,4,l:&p-3                       p = substr(p,4,strlen(p)-3) {get name}
 ago .d                                   goto .d
.c                                     .c
&len amid &p,1,1                          len = substr(p,1,1) {only first char}
&p amid &p,3,l:&p-2                       p = substr(p,3,strlen(p)-2) {get name}
.d                                     .d We have a name and its length
&p equ &totallen+&PClen+&work             {name} equ totallen+PClen+work
&totallen seta &totallen+&len             totallen = totallen+len (length of parm)
&i seta &i+1                              i = i + 1
 aif &i<=c:&parms,^b                      if i<#parms goto b (backwards goto)
.e                                     .e All parms setup (equ'd)
 tsc                                      get stack pointer
 aif &work=0,.f                           If you need work space...
 sec                                       add it onto the stack pointer
 sbc #&work
 tcs
.f                                       Stack is setup by here...
 phd                                      Save the direct page
 tcd                                      Set direct page == stack ptr
 mend                                     Thus lda parm is a direct page reference...

 MACRO
&lab port_return &returnparm,&comproutine
;
; Parse the return parameter (if defined).
;
&lab anop                                 Place any label from macro invocation
 lclc &len                                Local create len
 aif c:&returnparm,.a                     If there is a parameter goto .a
 lclc &returnparm                         Local create r (for parm length)
&returnparm setc 0