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1.1.1.2 root 1: ; Copyright 1992 Eric R. Smith
2:
1.1.1.5 ! root 3: ; Copyright 1993,1994 Atari Corporation
! 4:
1.1.1.2 root 5: ; All rights reserved.
6:
7:
8:
1.1 root 9: %include "magic.i"
10:
11: ;
12:
13: ; interrupt wrapping routines; these should just save registers and call
14:
15: ; the appropriate C handlers, unless speed is a major problem
16:
17: ;
18:
19: TEXT
20:
21: ;
22:
23: ; first, utilities for setting processor status level
24:
25: ;
26:
1.1.1.5 ! root 27: XDEF _spl7
! 28:
! 29: XDEF _spl
1.1 root 30:
31: _spl7:
32:
33: move.w sr,d0
34:
35: ori.w #$0700,sr
36:
37: rts
38:
39: _spl:
40:
1.1.1.3 root 41: move.w 4(sp),sr
1.1 root 42:
43: rts
44:
45:
46:
47: XDEF _mint_5ms
48:
49: XDEF _mint_timer
50:
51: XDEF _mint_vbl
52:
53: XREF _timeout ; C time routine
54:
55: XREF _old_timer ; old GEMDOS time vector
56:
57: XREF _old_vbl ; old GEMDOS vbl vector
58:
59: XREF _old_5ms
60:
61: XREF _build_context
62:
63: XREF _restore_context
64:
65: XREF _proc_clock ; controls process' allocation of CPU time
66:
67: XREF _curproc
68:
69: XREF _enter_kernel
70:
71: XREF _leave_kernel
72:
73: XREF _preempt
74:
75: XREF _in_kernel
76:
1.1.1.5 ! root 77: XREF _calc_load_average
! 78:
! 79: XREF _uptimetick
! 80:
! 81: XREF _checkbttys_vbl
! 82:
1.1 root 83:
84:
85: ; AKP: this code is hit once every 5ms; it updates the time fields of curproc.
86:
87: _mint_5ms:
88:
89: move.l a0,-(sp)
90:
1.1.1.5 ! root 91: subq.w #1,_uptimetick
! 92:
1.1 root 93: move.l _curproc,a0
94:
95: tst.w _in_kernel
96:
97: bne.s L_systime
98:
1.1.1.5 ! root 99: addq.l #5,P_USRTIME(a0) ; update curproc->usrtime
1.1 root 100:
101: move.l (sp)+,a0
102:
103: move.l _old_5ms+8,-(sp) ; branch to old vector
104:
105: rts
106:
107: L_systime:
108:
1.1.1.5 ! root 109: addq.l #5,P_SYSTIME(a0) ; update curproc->systime
1.1 root 110:
111: move.l (sp)+,a0
112:
113: move.l _old_5ms+8,-(sp)
114:
115: rts
116:
117:
118:
119: _mint_timer:
120:
121: movem.l d0-d2/a0-a2,-(sp) ; save C registers
122:
123: jsr _timeout
124:
125: movem.l (sp)+,d0-d2/a0-a2
126:
127: move.l _old_timer+8,-(sp) ; jump to GEMDOS time vector
128:
129: rts
130:
131:
132:
133: _mint_vbl:
134:
1.1.1.2 root 135: %ifndef ONLY030
136:
1.1 root 137: tst.w ($59e).w ; test longframe (AKP)
138:
139: beq.s L_short1
140:
1.1.1.2 root 141: %endif
142:
1.1 root 143: clr.w -(sp) ; yes, long frames: push a frame word
144:
145: L_short1:
146:
1.1.1.5 ! root 147: pea L_comeback(pc) ; push fake PC
1.1 root 148:
149: move.w sr,-(sp) ; push status register
150:
151: move.l _old_vbl+8,-(sp) ; go service the interrupt
152:
153: rts
154:
155:
156:
157: L_comeback:
158:
1.1.1.5 ! root 159: movem.l d0-d2/a0-a2,-(sp) ; save C registers
1.1.1.4 root 160:
1.1.1.5 ! root 161: jsr _checkbttys_vbl
1.1.1.4 root 162:
1.1.1.5 ! root 163: tst.w _uptimetick
1.1.1.4 root 164:
1.1.1.5 ! root 165: bgt.s L_no_uptime
1.1.1.4 root 166:
1.1.1.5 ! root 167: jsr _calc_load_average ; Go test if it's time to update uptime
! 168:
! 169: L_no_uptime:
! 170:
! 171: movem.l (sp)+,d0-d2/a0-a2
1.1.1.4 root 172:
1.1 root 173: tst.w _proc_clock ; has time expired yet?
174:
175: beq.s L_expired ; yes -- maybe go switch processes
176:
177: L_out:
178:
179: rte ; no -- just return
180:
181:
182:
183: L_expired:
184:
185: btst #5,(sp) ; user mode?
186:
187: bne.s L_out ; no -- switching is not possible
188:
189: tst.w ($43e).w ; test floppy disk lock variable
190:
191: bne.s L_out ; if locked, can't switch
192:
193: tst.w _in_kernel ; are we doing a kernel operation?
194:
195: bne.s L_out
196:
197: L_switch:
198:
199: clr.w -(sp) ; no frame format needed
200:
201: move.l _curproc,-(sp)
202:
1.1.1.2 root 203: addq.l #P_CTXT0,(sp) ; to get &curproc->ctxt[SYSCALL]
1.1 root 204:
205: jsr _build_context ; build context
206:
207: move.l _curproc,a0
208:
209: move.l (a0),sp ; use curproc->sysstack
210:
1.1.1.5 ! root 211: move.w P_CTXT0+C_SR(a0),d7 ; get saved int level
! 212:
! 213: %ifdef ONLY030
! 214:
! 215: clr.w -(sp) ; not a system call
! 216:
! 217: %else
! 218:
1.1.1.4 root 219: move.w #0,-(sp) ; not a system call
220:
1.1.1.5 ! root 221: %endif
! 222:
1.1 root 223: jsr _enter_kernel ; enter kernel
224:
1.1.1.4 root 225: addq.w #2,sp
226:
1.1.1.5 ! root 227: move.w sr,d1
! 228:
! 229: eor.w d1,d7
! 230:
! 231: and.w #$700,d7
! 232:
! 233: eor.w d7,d1
! 234:
! 235: move.w d1,sr ; vbl allowed again
! 236:
1.1 root 237: jsr _preempt ; yield processor
238:
239: ori.w #$700,sr ; spl7()
240:
241: jsr _leave_kernel ; restore vectors
242:
243: move.l _curproc,a0
244:
245: pea 4(a0)
246:
247: jsr _restore_context ; back to user
248:
249:
250:
251: ;
252:
253: ; reset routine -- called on a warm boot. Note that TOS sends the
254:
255: ; address to which we should return in register a6. Also note that
256:
257: ; the stack pointer is in an unknown state, so we set up our own
258:
259: ;
260:
261: XDEF _reset
262:
1.1.1.2 root 263: XREF _init_tail ; see main.c
1.1 root 264:
265: XREF _restr_intr
266:
267:
268:
269: _reset:
270:
271: move.w #$2700,sr ; avoid interruption here
272:
1.1.1.2 root 273: move.l sp,_init_tail ; save A7
1.1 root 274:
1.1.1.5 ! root 275: lea _init_tail+256,sp ; set up temporary stack
1.1 root 276:
277: movem.l d0-d2/a0-a2,-(sp) ; save C registers
278:
279: jsr _restr_intr ; restore interrupts
280:
281: movem.l (sp)+,d0-d2/a0-a2 ; restore registers
282:
1.1.1.2 root 283: move.l _init_tail,sp
1.1 root 284:
285: jmp (a6) ; reset again
286:
287:
288:
289: ;
290:
291: ; routine for doing a reboot
292:
293: ;
294:
295: XDEF _reboot
296:
297: _reboot:
298:
299: move.w #$2700,sr ; avoid interrupts
300:
301: move.l (0).w,sp ; get sp after reboot
302:
303: move.l (4).w,a6 ; get new reboot address
304:
305: jmp _reset
306:
307:
308:
309: ;
310:
311: ; routine for mouse packet handling
312:
313: ;
314:
315: XDEF _newmvec
316:
317: XDEF _newjvec
318:
319: XREF _mouse_handler
320:
321: ; Experimental three button mouse support (by [email protected],
322:
323: ; August 4, 1992
324:
325: ;
326:
327: ; Should work with the mice shipped with Atari's ASV or
328:
329: ; compatible ones (like Golden Image GI-6000). Might not work
330:
331: ; on ST/STE systems with older IKBD's or keyboards. The middle mouse
332:
333: ; button is wired to one of the joystick directions on joystick one.
334:
335: ;
336:
337: ; _newmvec is the same as before with two exceptions:
338:
339: ; 1. the first byte of the packet is saved for the joystick handler
340:
341: ; 2. the bit for the middle mouse button is ored in
342:
343: ;
344:
345: ; _newjvec hooks into the joystick vector and chains to the normal
346:
347: ; handler. The middle mouse button state is saved in a special
348:
349: ; register for _newmvec, and a 'fake' mouse packet is set up
350:
351: ; (by merging the last mouse packet header, or-ing in the
352:
353: ; middle button state and using 0/0 for the x/y increment).
354:
355: ;
356:
357: ; the faked_packet and third_button variables are declared at the
358:
359: ; end of this file
360:
361:
362:
363: _newmvec:
364:
365: move.l a0,-(sp)
366:
367: move.b (a0),d0
368:
369: move.b d0,faked_packet
370:
371: or.b third_button,d0
372:
373: move.b d0,(a0)
374:
375: jsr _mouse_handler
376:
377: move.l (sp)+,a0
378:
379: rts
380:
381: ;
382:
383: ; routine for joystick packet handling (used for three button mice)
384:
385: ;
386:
387: XDEF _newjvec
388:
389: XREF _oldjvec
390:
391:
392:
393: _newjvec:
394:
395: move.l a0,-(sp) ; save a0 on the stack
396:
397: move.b 2(a0),d0 ; joystick direction
398:
399: and.b #1,d0 ; middle mouse button in lowest bit
400:
401: add.b d0,d0 ; times 4
402:
403: add.b d0,d0
404:
405: move.b d0,third_button ; save it for use in newmvec
406:
407:
408:
409: lea faked_packet,a0 ; 'our' faked mouse event
410:
411: move.b (a0),d0
412:
413: and.b #$3,d0 ; unmask our mouse button
414:
415: or.b #$F8,d0 ; or in correct header
416:
417: or.b third_button,d0 ; or in the current status
418:
419: move.b d0,(a0) ; write it back
420:
421:
422:
423: move.l a0,-(sp) ; pass pointer to fake packet
424:
425: jsr _mouse_handler ; to \dev\mouse handler
426:
427: addq.l #4,sp ; pop parameter
428:
429: move.l (sp)+,a0 ; restore original a0 value
430:
431: move.l _oldjvec,-(sp) ; jump to original joystick handler
432:
433: rts
434:
435: ;
436:
437: ; new ikbd keyboard interrupt vector
438:
439: ; kintr is a global variable that should be non-zero if a keyboard
440:
441: ; event occured
442:
443: ;
444:
445: XDEF _new_ikbd
446:
447: XREF _old_ikbd
448:
449: XREF _kintr
450:
451:
452:
453: _new_ikbd:
454:
455: move.w #1,_kintr
456:
457: move.l _old_ikbd+8,-(sp)
458:
459: rts ; jump to system interrupt routine
460:
461:
462:
1.1.1.5 ! root 463: ; Generic routine for handling any user-specified interrupts. On 68000, the
! 464:
! 465: ; vector number is stored in the high byte of the program counter.
! 466:
! 467: ;
! 468:
! 469: XDEF _new_intr
! 470:
! 471: XDEF _sig_user
! 472:
! 473:
! 474:
! 475: _new_intr:
! 476:
! 477: movem.l d0-d2/a0-a2,-(sp) ; save regs
! 478:
! 479:
! 480:
! 481: %ifndef ONLY030
! 482:
! 483: tst.w ($59e).w ; is frame format on stack?
! 484:
! 485: bne.s nvec ; yes, go use it
! 486:
! 487: bsr.s ndummy ; push PC to stack
! 488:
! 489: nop
! 490:
! 491: ndummy:
! 492:
! 493: move.w (sp)+,d0 ; pop hi(PC) to d0
! 494:
! 495: addq.w #2,sp ; pop lo(PC) off stack
! 496:
! 497: lsr.w #8,d0 ; move hi byte to vector number
! 498:
! 499: bra.s ngot ; continue
! 500:
! 501: nvec:
! 502:
! 503: %endif
! 504:
! 505: move.w 30(sp),d0 ; get frame word
! 506:
! 507: lsr.w #2,d0 ; move vector offset to vector number
! 508:
! 509: ngot:
! 510:
! 511: move.w d0,-(sp) ; push vector offset
! 512:
! 513: jsr _sig_user ; send signal
! 514:
! 515: addq.w #2,sp ; pop vector offset
! 516:
! 517: movem.l (sp)+,d0-d2/a0-a2 ; restore regs
! 518:
! 519: rte
! 520:
! 521:
! 522:
1.1 root 523: ;
524:
525: ; simple signal handlers
526:
527: ; global variables referenced:
528:
529: ; in_kernel: (main.c): flag to indicate that we're in the MiNT kernel
530:
531: ; sig_routine: (signal.c): pointer to which signal catching routine to
532:
533: ; call (e.g. for SIGBUS, or whatever)
534:
535: ;
536:
537: XDEF _new_bus,_new_addr,_new_ill,_new_divzero,_new_priv,_new_linef
538:
539: XDEF _new_trace,_new_chk,_new_trapv,_new_fpcp,_new_mmu,_new_pmmuacc
540:
541: XDEF _new_uninit,_new_spurious,_new_format,_new_cpv
542:
543: XREF _in_kernel,_sig_routine
544:
545: XREF _sigbus,_sigaddr,_sigill,_sigfpe,_sigpriv,_sigtrap
546:
547: XREF _haltformat,_haltcpv
548:
549: XREF _sig_exc
550:
1.1.1.3 root 551: XREF _mcpu
552:
1.1 root 553:
554:
1.1.1.2 root 555: ;
556:
557: ; New bus error handler for memory protection: get the ssp and
558:
559: ; put it in the proc structure before calling
560:
561: ; _sigbus. When the bus error happens in the kernel we don't save
562:
563: ; any contexts.
564:
565: ; We don't want to mess up any registers here because we might bring the
566:
567: ; page in and RTE.
568:
569: ;
570:
571:
572:
1.1 root 573: _new_bus:
574:
1.1.1.3 root 575: %ifndef ONLY030
576:
1.1 root 577: move.w #$8,_sig_exc
578:
1.1.1.3 root 579: cmp.l #30,_mcpu
580:
581: bne.s noMMU
582:
583: %endif
584:
1.1.1.2 root 585: move.l #_mmu_sigbus,_sig_routine
1.1 root 586:
1.1.1.3 root 587: %ifndef ONLY030
588:
589: bra.s Do_sig
590:
591: noMMU:
592:
593: move.l #_nommu_sigbus,_sig_routine
594:
595: %endif
596:
1.1 root 597: Do_sig:
598:
1.1.1.2 root 599: move.l a0,-(sp) ; save a0
600:
601: move.l _curproc,a0
602:
603: move.l sp,P_EXCSSP(a0)
604:
605: addq.l #4,P_EXCSSP(a0)
606:
607: move.l 6(sp),P_EXCPC(a0)
608:
609: move.l (sp)+,a0
610:
611:
612:
1.1 root 613: tst.w _in_kernel ; are we already in the kernel?
614:
615: bne.s Kernel ; yes
616:
617: move.w _sig_exc,-(sp)
618:
619: move.l _curproc,-(sp)
620:
621: addq.l #4,(sp) ; push offset of save area
622:
623: jsr _build_context
624:
625: move.l _curproc,a4
626:
627: move.l (a4),sp ; put us in the system stack
628:
1.1.1.5 ! root 629: %ifdef ONLY030
! 630:
! 631: clr.w -(sp) ; not a GEMDOS call
! 632:
! 633: %else
! 634:
1.1.1.4 root 635: move.w #0,-(sp) ; not a GEMDOS call
636:
1.1.1.5 ! root 637: %endif
! 638:
1.1 root 639: jsr _enter_kernel ; set up kernel vectors
640:
1.1.1.4 root 641: addq.w #2,sp
642:
1.1 root 643: move.l _sig_routine,a1 ; get signal handling routine
644:
645: jsr (a1) ; go do it
646:
647: ori.w #$0700,sr ; spl7()
648:
649: jsr _leave_kernel ; leave kernel
650:
651: addq.w #4,a4 ; get context save area address
652:
653: move.l a4,-(sp) ; push it
654:
655: jsr _restore_context ; restore the context
656:
657: ;
658:
659: ; here's what we do if we already were in the kernel
660:
661: ;
662:
663: Kernel:
664:
665: movem.l d0-d2/a0-a2,-(sp) ; save reggies
666:
667: move.l _sig_routine,a1 ; get handler
668:
669: jsr (a1) ; go do it
670:
671: movem.l (sp)+,d0-d2/a0-a2
672:
673: rte
674:
1.1.1.2 root 675:
676:
677: ;
678:
679: ; _mmu_sigbus: a pre-handler for _sigbus. Check the reason for the bus
680:
681: ; error and report if it was a real access fault.
682:
683: ;
684:
685: _mmu_sigbus:
686:
687: move.l a2,-(sp)
688:
689: move.l _curproc,a0
690:
691: move.l P_EXCSSP(a0),a1 ; a1 is now exception_ssp
692:
693: move.w $A(a1),d0 ; d0 is SSR
694:
695: move.l $10(a1),a1 ; a1 is the access address
696:
697: move.l a1,P_EXCADDR(a0) ; save the access address
698:
699:
700:
701: ptestr d0,(a1),#7,a2 ; a2 is the table address
702:
703: move.l a2,P_EXCTBL(a0) ; save table address in curproc
704:
705: pmove mmusr,P_EXCMMUSR(a0) ; save resulting mmusr in curproc
706:
707: move.l (sp)+,a2
708:
709: jmp _sigbus ; chain to bus-error handler
710:
1.1.1.3 root 711: %ifndef ONLY030
712:
713: ;
714:
715: ; _nommu_sigbus: handler for bus errors on machines without MMU
716:
717:
718:
719: _nommu_sigbus:
720:
721: move.l _curproc,a0
722:
723: move.l P_EXCSSP(a0),a1
724:
725: lea $10(a1),a1 ; point to access address
726:
727: tst.w ($59e).w ; test longframe
728:
729: beq.s NOMMU1
730:
731: addq.w #8,a1 ; on 68000, address is 8 bytes further
732:
733: NOMMU1:
734:
735: move.l (a1),P_EXCADDR(a0) ; save the access address
736:
737: jmp _sigbus
738:
739: %endif
740:
1.1.1.2 root 741:
742:
1.1 root 743: _new_addr:
744:
1.1.1.3 root 745: %ifndef ONLY030
746:
1.1 root 747: move.w #$c,_sig_exc
748:
1.1.1.3 root 749: %endif
750:
1.1 root 751: move.l #_sigaddr,_sig_routine
752:
1.1.1.2 root 753: bra Do_sig
1.1 root 754:
755: _new_ill:
756:
1.1.1.3 root 757: %ifndef ONLY030
758:
1.1 root 759: move.w #$10,_sig_exc
760:
1.1.1.3 root 761: %endif
762:
1.1 root 763: move.l #_sigill,_sig_routine
764:
1.1.1.2 root 765: bra Do_sig
1.1 root 766:
767: _new_divzero:
768:
1.1.1.3 root 769: %ifndef ONLY030
770:
1.1 root 771: move.w #$14,_sig_exc
772:
1.1.1.3 root 773: %endif
774:
1.1 root 775: move.l #_sigfpe,_sig_routine
776:
777: bra Do_sig
778:
779: _new_linef:
780:
1.1.1.3 root 781: %ifndef ONLY030
782:
1.1 root 783: move.w #$2c,_sig_exc
784:
1.1.1.3 root 785: %endif
786:
1.1 root 787: move.l #_sigill,_sig_routine
788:
789: bra Do_sig
790:
791: _new_chk:
792:
1.1.1.3 root 793: %ifndef ONLY030
794:
1.1 root 795: move.w #$18,_sig_exc
796:
1.1.1.3 root 797: %endif
798:
1.1 root 799: move.l #_sigfpe,_sig_routine
800:
801: bra Do_sig
802:
803: _new_trapv:
804:
1.1.1.3 root 805: %ifndef ONLY030
806:
1.1 root 807: move.w #$1c,_sig_exc
808:
1.1.1.3 root 809: %endif
810:
1.1 root 811: move.l #_sigfpe,_sig_routine
812:
813: bra Do_sig
814:
815: _new_fpcp:
816:
817: ; don't set _sig_exc - only needed for 68000 vectors
818:
819: move.l #_sigfpe,_sig_routine
820:
821: bra Do_sig
822:
823: _new_mmu:
824:
825: ; don't set _sig_exc - only needed for 68000 vectors
826:
827: move.l #_sigill,_sig_routine
828:
829: bra Do_sig
830:
831: _new_pmmuacc:
832:
833: ; don't set _sig_exc - only needed for 68000 vectors
834:
835: move.l #_sigbus,_sig_routine
836:
837: bra Do_sig
838:
839: _new_uninit:
840:
1.1.1.3 root 841: %ifndef ONLY030
842:
1.1 root 843: move.w #$3c,_sig_exc
844:
1.1.1.3 root 845: %endif
846:
1.1 root 847: move.l #_sigbus,_sig_routine
848:
849: bra Do_sig
850:
851: _new_spurious:
852:
1.1.1.3 root 853: %ifndef ONLY030
854:
1.1 root 855: move.w #$60,_sig_exc
856:
1.1.1.3 root 857: %endif
858:
1.1 root 859: move.l #_sigbus,_sig_routine
860:
861: bra Do_sig
862:
863: _new_format:
864:
865: move.l #_haltformat,_sig_routine
866:
867: bra Do_sig
868:
869: _new_cpv:
870:
871: move.l #_haltcpv,_sig_routine
872:
873: bra Do_sig
874:
875:
876:
877: XREF _old_priv ; old privilege violation vector
878:
879: _new_priv:
880:
1.1.1.3 root 881: %ifndef ONLY030
882:
1.1 root 883: move.w #$20,_sig_exc
884:
1.1.1.3 root 885: %endif
886:
1.1 root 887: move.l #_sigpriv,_sig_routine
888:
1.1.1.3 root 889: %ifndef ONLY030
1.1.1.2 root 890:
1.1 root 891: tst.w ($59e).w ; 68000s always get SIGPRIV
892:
893: beq Do_sig
894:
1.1.1.2 root 895: %endif
896:
1.1 root 897: movem.l d0/a0,-(a7)
898:
899: move.l 10(a7),a0 ; fetch exception address
900:
901: move.w (a0),d0
902:
903: and.w #$ffc0,d0 ; partially decode move sr,...
904:
905: cmp.w #$40c0,d0 ; and test it
906:
907: movem.l (a7)+,d0/a0 ; preserves the flags
908:
909: bne Do_sig ; doesn't look like sr,...
910:
911: move.l _old_priv+8,-(sp) ; let our parent handle it
912:
913: rts
914:
915:
916:
917: ; XBRA vectors from main.c
918:
919: XREF _old_dos,_old_bios,_old_xbios
920:
921: XREF _old_divzero,_old_chk,_old_trapv
922:
923:
924:
925: _new_trace:
926:
927: btst #5,(a7) ; only check when called from supervisor mode
928:
929: beq.s S_1
930:
931: cmp.l #_old_dos+12,2(a7) ; lets not trace the kernel !
932:
933: beq.s S_2
934:
935: cmp.l #_old_xbios+12,2(a7)
936:
937: beq.s S_2
938:
939: cmp.l #_old_bios+12,2(a7)
940:
941: beq.s S_2
942:
943: cmp.l #_old_divzero+12,2(a7)
944:
945: beq.s S_2
946:
947: cmp.l #_old_trapv+12,2(a7)
948:
949: beq.s S_2
950:
951: cmp.l #_old_chk+12,2(a7)
952:
953: beq.s S_2
954:
955: ; add any other non-traceable entities here...
956:
957:
958:
959: S_1: move.w #$24,_sig_exc
960:
961: move.l #_sigtrap,_sig_routine
962:
963: bra Do_sig
964:
965:
966:
967: S_2: and.w #$3fff,(a7) ; clear both trace bits
968:
969: rte ; and re-start the handler
970:
971:
972:
973: ;
974:
975: ; BIOS disk vectors for pseudo-disks like U: and X:; these are present
976:
977: ; just in case some program (foolishly) attempts to access these drives
978:
979: ; directly and gets horribly confused
980:
981: ;
982:
983: XREF _old_getbpb ; old Getbpb vector
984:
985: XREF _old_mediach ; old Mediach vector
986:
987: XREF _old_rwabs ; old Rwabs vector
988:
989: XREF _aliasdrv ; array of drive aliases
990:
991: XDEF _new_getbpb
992:
993: XDEF _new_mediach
994:
995: XDEF _new_rwabs
996:
997:
998:
999: _new_getbpb:
1000:
1001: move.w 4(sp),d0 ; check the drive
1002:
1.1.1.2 root 1003: cmp.w #$1f,d0 ; legal drive?
1004:
1005: bhi.s noalias0 ; no
1006:
1.1 root 1007: move.w d0,d1 ; get index
1008:
1009: add.w d0,d1 ; convert to index
1010:
1011: lea _aliasdrv,a0
1012:
1013: move.w 0(a0,d1.w),d1 ; alias drive?
1014:
1015: beq.s noalias0
1016:
1017: move.w d1,d0
1018:
1019: subq.w #1,d0 ; adjust for aliasdrv base of '@'
1020:
1021: cmp.w #$1f,d0 ; is this a legal drive?
1022:
1023: bhi.s nobpb ; no -- ignore it
1024:
1.1.1.2 root 1025: noalias0:
1026:
1.1 root 1027: cmp.w #$14,d0 ; drive U:?
1028:
1029: beq.s nobpb ; yes, no BPB available
1030:
1031: move.l _old_getbpb+8,a0 ; not our drive
1032:
1033: jmp (a0) ; call the old vector for it
1034:
1035: nobpb:
1036:
1037: moveq.l #0,d0 ; 0 means "no BPB read"
1038:
1039: rts
1040:
1041:
1042:
1043: _new_mediach:
1044:
1045: move.w 4(sp),d0 ; check the drive
1046:
1.1.1.2 root 1047: cmp.w #$1f,d0 ; legal drive?
1048:
1049: bhi.s noalias1 ; no
1050:
1.1 root 1051: move.w d0,d1 ; get index
1052:
1053: add.w d0,d1 ; convert to index
1054:
1055: lea _aliasdrv,a0
1056:
1057: move.w 0(a0,d1.w),d1 ; alias drive?
1058:
1059: beq.s noalias1
1060:
1061: move.w d1,d0
1062:
1063: subq.w #1,d0 ; adjust for aliasdrv base
1064:
1065: cmp.w #$1f,d0 ; legal drive?
1066:
1067: bhi.s nobpb ; no -- ignore it
1068:
1.1.1.2 root 1069: noalias1:
1070:
1.1 root 1071: cmp.w #$14,d0 ; drive U:?
1072:
1073: beq.s nochng ; yes, no change
1074:
1075: move.l _old_mediach+8,a0 ; not our drive
1076:
1077: jmp (a0) ; call the old vector for it
1078:
1079: nochng:
1080:
1081: moveq.l #0,d0 ; 0 means "definitely no change"
1082:
1083: rts
1084:
1085:
1086:
1087: _new_rwabs:
1088:
1089: move.w $e(sp),d0 ; check the drive
1090:
1.1.1.2 root 1091: cmp.w #$1f,d0 ; legal drive?
1092:
1093: bhi.s noalias2 ; no
1094:
1.1 root 1095: move.w d0,d1 ; get index
1096:
1097: add.w d0,d1 ; convert to index
1098:
1099: lea _aliasdrv,a0
1100:
1101: move.w 0(a0,d1.w),d1 ; alias drive?
1102:
1103: beq.s noalias2
1104:
1105: move.w d1,d0
1106:
1107: subq.w #1,d0 ; adjust for aliasdrv base
1108:
1109: cmp.w #$1f,d0 ; legal drive?
1110:
1111: bhi.s nobpb ; no -- ignore it
1112:
1.1.1.2 root 1113: noalias2:
1114:
1.1 root 1115: cmp.w #$14,d0 ; drive U:?
1116:
1117: beq.s rwdone ; yes, fake it
1118:
1119: move.l _old_rwabs+8,a0 ; not our drive
1120:
1121: jmp (a0) ; call the old vector for it
1122:
1123: rwdone:
1124:
1125: moveq.l #0,d0 ; 0 means "successful operation"
1126:
1127: rts
1128:
1129:
1130:
1131: DATA
1132:
1133: ; buffer for faked mouse packet (actually only 3 bytes)
1134:
1135:
1136:
1137: faked_packet:
1138:
1139: dc.l 0
1140:
1141:
1142:
1143: ; here we store the additional button state
1144:
1145: third_button:
1146:
1147: dc.w 0
1148:
1149:
1150:
1151: END
1152:
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