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cc65/libsrc/apple2/exec.s
2015-04-27 09:39:50 +02:00

292 lines
8.4 KiB
ArmAsm

;
; Oliver Schmidt, 2011-01-26
;
; int __fastcall__ exec (const char* progname, const char* cmdline);
;
.export _exec
.import pushname, popname
.import popax, done, _exit
.include "zeropage.inc"
.include "errno.inc"
.include "apple2.inc"
.include "mli.inc"
; Wrong file type
typerr: lda #$4A ; "Incompatible file format"
; Cleanup name
oserr: jsr popname ; Preserves A
; Set __oserror
jmp __mappederrno
_exec:
; Save cmdline
sta ptr4
stx ptr4+1
; Get and push name
jsr popax
jsr pushname
bne oserr
; ProDOS TechRefMan, chapter 5.1.5.1:
; "The complete or partial pathname of the system program
; is stored at $280, starting with a length byte."
; In fact BASIC.SYSTEM does the same for BLOAD and BRUN of
; binary programs so we should do the same too in any case
; especially as _we_ rely on it in mainargs.s for argv[0]
ldy #$00
lda (sp),y
tay
: lda (sp),y
sta $0280,y
dey
bpl :-
; Set pushed name
lda sp
ldx sp+1
sta mliparam + MLI::INFO::PATHNAME
stx mliparam + MLI::INFO::PATHNAME+1
; Get file_type and aux_type
lda #GET_INFO_CALL
ldx #GET_INFO_COUNT
jsr callmli
bcs oserr
; If we get here the program file at least exists so we copy
; the loader stub right now and patch it later to set params
ldx #size - 1
: lda source,x
sta target,x
dex
bpl :-
; Check program file type
lda mliparam + MLI::INFO::FILE_TYPE
cmp #$FF ; SYS file?
bne binary ; No, check for BIN file
sta file_type ; Save file type for cmdline handling
; SYS programs replace BASIC.SYSTEM so set in the ProDOS system bit map
; protection for pages $80 - $BF just in case BASIC.SYSTEM is there now
ldx #$0F ; Start with protection for pages $B8 - $BF
lda #%00000001 ; Protect only system global page
: sta $BF60,x ; Set protection for 8 pages
lda #%00000000 ; Protect no page
dex
bpl :-
bmi prodos ; Branch always
binary: cmp #$06 ; BIN file?
bne typerr ; No, wrong file type
; Set BIN program load addr
lda mliparam + MLI::INFO::AUX_TYPE
ldx mliparam + MLI::INFO::AUX_TYPE+1
sta data_buffer
stx data_buffer+1
; Check ProDOS system bit map for presence of BASIC.SYSTEM
lda $BF6F ; Protection for pages $B8 - $BF
cmp #%00000001 ; Exactly system global page is protected
beq setvec
; Get highest available mem addr from BASIC.SYSTEM
ldx HIMEM+1 ; High byte
bne setbuf ; Branch always
; BIN programs are supposed to quit through one of the two DOS
; vectors so we set up those to point to the ProDOS dispatcher
setvec: ldx #$03 - 1 ; Size of JMP opcode
: lda dosvec,x
sta DOSWARM,x ; DOS warm start
sta DOSWARM + 3,x ; DOS cold start
dex
bpl :-
; No BASIC.SYSTEM so use addr of ProDOS system global page
prodos: ldx #>$BF00 ; High byte
; The I/O buffer needs to be page aligned
setbuf: lda #$00 ; Low byte
; The I/O buffer needs four pages
dex
dex
dex
dex
; Set I/O buffer
sta mliparam + MLI::OPEN::IO_BUFFER
stx mliparam + MLI::OPEN::IO_BUFFER+1
; PATHNAME already set
.assert MLI::OPEN::PATHNAME = MLI::INFO::PATHNAME, error
; Lower file level to avoid program file
; being closed by C libary shutdown code
ldx LEVEL
stx level
beq :+
dec LEVEL
; Open file
: lda #OPEN_CALL
ldx #OPEN_COUNT
jsr callmli
; Restore file level
ldx level
stx LEVEL
bcc :+
jmp oserr
; Get and save fd
: lda mliparam + MLI::OPEN::REF_NUM
sta read_ref
sta close_ref
.ifdef __APPLE2ENH__
; Calling the 80 column firmware needs the ROM switched
; in, otherwise it copies the F8 ROM to the LC (@ $CEF4)
bit $C082
; ProDOS TechRefMan, chapter 5.3.1.3:
; "80-column text cards -- and other Apple IIe features -- can
; be turned off using the following sequence of instructions:"
lda #$15
jsr $C300
; Switch in LC bank 2 for R/O
bit $C080
.endif
; Reset stack as we already passed
; the point of no return anyway
ldx #$FF
txs
; Store up to 127 chars of cmdline (if any)
; including terminating zero in stack page
ldy #$00
lda ptr4+1 ; NULL?
beq :++ ; Yes, store as '\0'
: lda (ptr4),y
: sta $0100,y
beq :+ ; '\0' stored, done
iny
cpy #$7E
bcc :--
lda #$00 ; '\0'
beq :- ; Branch always
; Call loader stub after C libary shutdown
: lda #<target
ldx #>target
sta done+1
stx done+2
; Initiate C libary shutdown
jmp _exit
.bss
level : .res 1
.rodata
; Read whole program file
source: jsr $BF00
.byte READ_CALL
.word read_param
bcs error
; Close program file
jsr $BF00
.byte CLOSE_CALL
.word close_param
bcs error
; Check for cmdline handling
lda $0100 ; Valid cmdline?
beq jump ; No, jump to program right away
ldx file_type ; SYS file?
bne system ; Yes, check for startup filename
; Store REM and cmdline in BASIC input buffer
lda #$B2 ; REM token
bne :++ ; Branch always
: inx
lda a:$0100-1,x
: sta $0200,x
bne :--
beq jump ; Branch always
; Check for startup filename support
; ProDOS TechRefMan, chapter 5.1.5.1:
; "$2000 is a jump instruction. $2003 and $2004 are $EE."
system: lda $2000
cmp #$4C
bne jump
lda $2003
cmp #$EE
bne jump
lda $2004
cmp #$EE
bne jump
; Store cmdline in startup filename buffer
ldx #$01
: lda a:$0100-1,x
beq :+
sta $2006,x
inx
cpx $2005 ; Buffer full?
bcc :- ; No, continue
: dex
stx $2006 ; Store cmdline length
; Go for it ...
jump: jmp (data_buffer)
file_type = * - source + target
.byte $00
read_param = * - source + target
.byte $04 ; PARAM_COUNT
read_ref = * - source + target
.byte $00 ; REF_NUM
data_buffer = * - source + target
.addr $2000 ; DATA_BUFFER
.word $FFFF ; REQUEST_COUNT
.word $0000 ; TRANS_COUNT
close_param = * - source + target
.byte $01 ; PARAM_COUNT
close_ref = * - source + target
.byte $00 ; REF_NUM
; Quit to ProDOS dispatcher
quit = * - source + target
error: jsr $BF00
.byte $65 ; QUIT
.word quit_param
quit_param = * - source + target
.byte $04 ; PARAM_COUNT
.byte $00 ; QUIT_TYPE
.word $0000 ; RESERVED
.byte $00 ; RESERVED
.word $0000 ; RESERVED
size = * - source
target = DOSWARM - size
dosvec: jmp quit