Apple-2-SW/A2osX
1
0
Fork 0
mirror of https://github.com/A2osX/A2osX.git synced 2025-02-19 23:29:29 +00:00
Code Issues Projects Releases Wiki Activity
A2osX/ProDOS.203/ProDOS.S.XDOS.txt
Rémy GIBERT bdcf96401e Kernel 0.93+
2019-09-10 22:53:18 +02:00

1757 lines
54 KiB
Plaintext
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

NEW
AUTO 3,1
* object code = mli_2
* xdos mli system call processor
.OP 65C02
ofsX .EQ xdosobj-xdosorg offset to xdos org
xdosmli .EQ *-ofsX xdos MLI in aux ram
xdosobj cld no decimal.
pla get processor status
sta spare1 save it temporarily
sty mliy save x and y
stx mlix
pla find out the address of the caller
sta A3L
clc preserve the address of the call spec.
adc #$04
sta mliretn last MLI call return address
pla
sta A3L+1
adc #$00
sta mliretn+1
lda spare1
pha pull processor status
plp to re-enable interrupts.
cld still no decimal
ldy #$00
sty p8error clear any previous errors.
iny find out if command is valid.
lda (A3L),y get command #
lsr a and hash it to a range of 0-$1F
lsr a
lsr a
lsr a
clc
adc (A3L),y
and #$1F
tax
lda (A3L),y check result to see if valid command #
cmp scnums,x
bne scnerr
iny index to call spec parm list.
lda (A3L),y make A3L point to parameter count byte
pha in parameter block.
iny
lda (A3L),y
sta A3L+1
pla
sta A3L
ldy #$00 make sure parameter list has the
lda pcntbl,x correct # of parameters.
beq goclock clock has 0 parameters.
cmp (A3L),y
bne scperr error if wrong count.
lda scnums,x get call # again
cmp #$65 is it quit?
beq special if so, then call quit dispatcher
asl carry set if bfm or dev mgr
bpl godevmgr
bcs gobfmgr
lsr a shift back down for interrupt manager
and #$03 valid calls are 0 and 1
jsr intmgr
bra exitmli
special jmp jspare P8 system death vector
goclock jsr clockv go read clock.
bra exitmli no errors possible
godevmgr lsr a shift back down for device manager.
adc #$01 valid commands are 1 and 2.
sta A4L save command #.
jsr devmgr execute read or write request.
bra exitmli
gobfmgr lsr a shift back down for block file manager.
and #$1F valid commands are 0-$13
tax
jsr bfmgr
exitmli stz bubit clear backup bit
ldy p8error P8 error code
cpy #$01 if > 0 then set carry
tya and set z flag.
php disable interrupts until exit complete.
sei
lsr mliact indicate MLI done.
plx save status register until return.
lda mliretn+1 place last MLI call return address
pha on stack. return is done via 'rti'
lda mliretn so the status register is restored
pha at the same time, so
phx place status back on stack
tya return error, if any.
ldx mlix MLI X register savearea
ldy mliy MLI Y register savearea
pha
lda bnkbyt1 restore language card status
jmp HBFA0 and return.
nodevice .EQ *-ofsX
lda #$28 no device connected.
jsr p8errv P8 error vector.
scnerr lda #$01 no such command.
bne H30B0
scperr lda #$04 parameter count is invalid
H30B0 jsr gosyserr
bcs exitmli always taken
* ProDOS Device Manager
devmgr .EQ *-ofsX
ldy #$05
php do not allow interrupts.
sei the call spec for devices must
H30B9 lda (A3L),y be passed to drivers in page zero:
sta |A4L),y sta $0042,y
dey
bne H30B9
ldx buf+1 buffer page
stx usrbuf+1 to user buffer
inx
inx
lda buf is buffer page aligned (nn00) ?
beq H30CC branch if it is
inx else account for 3-page straddle
H30CC jsr vldbuf1 make sure user buffer is not
bcs dvmgrerr conflicting with protected ram.
jsr dmgr call internal entry for device dispatch
bcs dvmgrerr branch if error
plp
clc no error
rts
dvmgrerr plp restore interrupt status
gosyserr .EQ *-ofsX
jsr p8errv P8 error vector
dmgr .EQ *-ofsX interrupts must always be off.
lda unitnum get device # and
and #$F0 strip misc lower nibble
sta unitnum then save it.
lsr a use as index to device table
lsr a
lsr a
tax
lda drivertbl1,x fetch driver address
sta goadr
lda drivertbl1+1,x
sta goadr+1
gocmd .EQ *-ofsX
jmp (goadr) goto driver (or error if no driver)
* ProDOS interrupt manager
intmgr .EQ *-ofsX
sta A4L interrupt command
lsr a allocate interrupt or deallocate?
bcs dealcint branch if deallocate.
ldx #$03 test for a free interrupt space in tbl.
alcint lda inttbl-2,x test high address for 0.
bne H3118 branch if spot occupied.
ldy #$03 get address of routine.
lda (A3L),y must not be zero page.
beq badint error if it is.
sta inttbl-2,x save high address
dey
lda (A3L),y
sta inttbl-3,x and low address.
txa return interrupt # in range 1-4
lsr a
dey
sta (A3L),y pass back to user.
clc no errors.
rts
H3118 inx
inx next lower priority spot
cpx #$0B are all 4 already allocated?
bne alcint branch if not.
lda #$25 interrupt table full
bne H3124
badint lda #$53 invalid parameter.
H3124 jsr p8errv P8 error vector.
dealcint ldy #$01 zero out interrupt vector
lda (A3L),y but make sure it is a valid #.
beq badint error if < 1
cmp #$05 or > 4
bcs badint
asl
tax
lda #$00 now clear it
sta inttbl-2,x
sta inttbl-1,x
clc
rts
irqrecev .EQ *-ofsX
lda accsav get acc from where old ROM put it.
sta p8areg
stx p8xreg entry point on ram card interrupt
sty p8yreg
tsx
stx p8sreg
lda irqflag irq flag = 0 if old roms
bne H315D and 1 if new roms.
pla restore return address and p-reg.
sta p8preg
pla
sta intadr interrupt return address
pla
sta intadr+1
H315D txs
lda mslot set up to re-enable $Cn00 rom
sta irqdev+2
tsx make sure stack has room for 16 bytes.
bmi H3170 branch if stack ok
ldy #$0F otherwise, make room and save it.
H3169 pla
sta svstack,y
dey
bpl H3169
H3170 ldx #$FA save 6 bytes of page 0
H3172 lda $00,x
sta svzerop-$FA,x
inx
bne H3172
* poll interrupt routines for a claimer
lda inttbl+1 test for a valid routine.
beq intr2 branch if no routine.
jsr goint1 execute
bcc irqdone
intr2 lda inttbl+3 repeat 3 more times
beq intr3
jsr goint2
bcc irqdone
intr3 lda inttbl+5
beq intr4
jsr goint3
bcc irqdone
intr4 lda inttbl+7
beq H31A2
jsr goint4
bcc irqdone
H31A2 inc irqcount allow 255 unclaimed interrupts
bne irqdone before system death.
lda #$01 bad irq so
jsr sysdeath kill the system.
irqdone ldx #$FA
H31AE lda svzerop-$FA,x restore the zero page
sta $00,x
inx
bne H31AE
ldx p8sreg test if stack needs restoring.
bmi H31C6 branch if not.
ldy #$00
H31BD lda svstack,y restore stack
pha
iny
cpy #$10
bne H31BD
H31C6 lda irqflag check for old roms.
bne H31DD branch if new roms.
ldy p8yreg restore registers.
ldx p8xreg
lda clrrom re-enable i/o card.
irqdev .EQ *-ofsX
lda $C100 Cn is self modifying.
lda irqdev+2 restore device id.
sta mslot slot being accessed.
H31DD jmp irqexit do necessary bank switches and return.
irqflag .EQ *-ofsX
.HS 00 0 = old roms. 1 = new roms.
irqcount .EQ *-ofsX
.HS 00 # of unclaimed interrupts.
svstack .EQ *-ofsX temporary save area from stack
.HS 0000000000000000
.HS 0000000000000000
svzerop .EQ *-ofsX temporary save area for zero page
.HS 000000000000
goint1 .EQ *-ofsX
jmp (inttbl) interrupt routine 1
goint2 .EQ *-ofsX
jmp (inttbl+2) interrupt routine 2
goint3 .EQ *-ofsX
jmp (inttbl+4) interrupt routine 3
goint4 .EQ *-ofsX
jmp (inttbl+6) interrupt routine 4
syserr1 .EQ *-ofsX
sta p8error P8 error code
plx
plx pop 1 level of return
sec
rts
sysdeath1 .EQ *-ofsX
tax death error code.
sta clr80vid disable 80 col hardware.
lda txtset switch in text.
lda cortflag is this a Cortland?
beq H321A if not, don't use super hires switch.
stz newvideo force off super hires.
H321A lda txtpage1 switch in text page 1.
ldy #$13
H321F lda #$20 inverse space border
sta vline11+10,y
sta vline13+10,y
lda deathmsg,y
sta vline12+10,y 'RESTART SYSTEM-$0x'
dey
bpl H321F
txa x = death error code
and #$0F convert to ascii
ora #$B0
cmp #$BA
bcc H323B branch if not > 9.
adc #$06 inc to alpha a-f
H323B sta vline12+28 death error code 1 to F
H323E bra H323E end of xdos mli
* ProDOS Block File Manager
bfmgr .EQ *-ofsX
lda disptch,x translate into command address.
asl bit 7 indicates pathname to process
sta cmdtemp
and #$3F bit 6 is refnum, 5 is time to process
tax
lda cmdtable,x move address to indirect jump
sta goadr
lda cmdtable+1,x high byte
sta goadr+1
lda #$20 init backup bit flag
sta bkbitflg to say 'file modified'
bcc nopath
jsr setpath process pathname before calling command
bcs errorsys branch if bad name.
nopath asl cmdtemp test for refnum processing
bcc nopreref
jsr findfcb set pointers to fcb and vcb of file
bcs errorsys
nopreref asl cmdtemp check for necessity of time stamp
bcc H3274
jsr clockv date/time
H3274 jsr gocmd execute command
bcc goodop
errorsys jsr p8errv P8 error vector
goodop rts
setpath .EQ *-ofsX
ldy #$01 index to pathname pointer
lda (A3L),y low pointer address
sta zpt
iny
lda (A3L),y hi pointer address
sta zpt+1
synpath .EQ *-ofsX entry used by rename for 2nd pathname.
ldx #$00 x = index to pathbuf
ldy #$00 y = index to input pathname.
stx prfxflg assume prefix is in use.
stx pathbuf mark pathbuf = nothing processed.
lda (zpt),y validate pathname length > 0 and < 65
beq errsyn
cmp #$41
bcs errsyn
sta pathcnt this is used to compare for
inc pathcnt end of pathname processing.
iny now check for full pathname...
lda (zpt),y (full name if starts with '/')
ora #$80
cmp #$AF
bne H32AD branch if prefix appended.
sta prfxflg set prefix flag = prefix not used.
iny index to 1st character of pathname.
H32AD lda #$FF set current position of pathbuf
sta pathbuf,x to indicate end of pathname.
sta namcnt $FF = no chars processed in local name.
stx namptr pointer to local name length byte.
H32B8 cpy pathcnt done with pathname processing?
bcs endpath
lda (zpt),y get character
and #$7F
inx prepare for next char
iny
cmp #$2F is it delimiter '/' ?
beq endname yes
cmp #$61 lowercase?
bcc H32CD no
and #$5F shift to uppercase
H32CD sta pathbuf,x store char
inc namcnt is it the 1st char of a local name?
bne H32DA no
inc namcnt increment to 1
bne H32E6 1st char must be alpha (always taken)
H32DA cmp #$2E is it '.' ?
beq H32B8 ok, then do next char
cmp #$30 at least a '0' ?
bcc errsyn error if not
cmp #$3A is it numeric?
bcc H32B8 yes, get next char
H32E6 cmp #$41 at least an 'a' ?
bcc errsyn error if not
cmp #$5B is it > 'z' ?
bcc H32B8 branch if valid alpha to get next char
errsyn sec bad pathname
lda #$40
rts
endpath lda #$00 end pathname with a 0
bit namcnt also make sure count is positive
bpl H32FD
sta namcnt
dex
H32FD inx
sta pathbuf,x
beq errsyn error if '/' only.
stx pathcnt save length of pathname
tax
endname lda namcnt validate local name < 16
cmp #$10
bcs errsyn
phx save pointer
ldx namptr get index to beginning of local name
sta pathbuf,x save local name's length
plx restore pointer
bne H32AD branch if more names to process
clc probably no error, but
lda prfxflg make sure all pathnames are prefixed
bne H3323 or begin with a '/'.
lda newpfxptr must be non-zero
beq errsyn
H3323 rts
* set prefix command
setprefx .EQ *-ofsX
jsr setpath call is made to detect if a null path.
bcc H3333 path ok.
ldy pathbuf is it a null pathname?
bne pfxerr error if not
jsr stypfx indicate null prefix
clc no error
rts
H3333 jsr findfile go find specified prefix directory.
bcc H333C if no error.
cmp #$40 bad pathname.
bne pfxerr branch if error is not root directory.
H333C lda d_stor make sure last local name is dir type
and #$D0 (either root or sub).
eor #$D0 directory?
bne ptyperr wrong type
ldy prfxflg new or appended prefix?
bne H334D
lda newpfxptr append new prefix to old
H334D tay
sec find new beginning of prefix
sbc pathcnt
cmp #$C0 too long?
bcc errsyn then error
tax
jsr stapfx
lda d_dev save device #
sta p_dev
lda d_frst and address of 1st block
sta p_blok
lda d_frst+1
sta p_blok+1
movprfx lda pathbuf,y
sta pathbuf,x
iny
inx
bne movprfx
clc good prefix
rts
ptyperr lda #$4B filetype error (not a directory)
pfxerr sec
rts
* get prefix command
getprefx .EQ *-ofsX calc how big a buffer is needed.
clc get index to users pathname buffer
ldy #$01
lda (A3L),y
sta usrbuf user buffer ptr
iny
lda (A3L),y
sta usrbuf+1
stz cbytes+1 set buffer length at 64 char max
lda #$40
sta cbytes
jsr valdbuf go validate prefix buffer address
bcs pfxerr
ldy #$00 y = indirect index to user buffer.
lda newpfxptr get address of beginning of prefix
tax
beq nulprfx if null prefix.
eor #$FF get total length of prefix
adc #$02 add 2 for leading and trailing slashes.
nulprfx sta (usrbuf),y store length in user's buffer.
beq gotprfx branch if null prefix.
sendprfx iny inc to next user buffer location.
lda pathbuf,x get next char of prefix.
sndlimit sta (usrbuf),y give char to user.
and #$F0 check for length descriptor.
bne H33B3 branch if regular character
lda #$2F otherwise, substitute a slash.
bne sndlimit branch always
H33B3 inx
bne sendprfx branch if more to send.
iny
lda #$2F end with '/'
sta (usrbuf),y
gotprfx clc no error
rts
findfcb .EQ *-ofsX
ldy #$01 index to ref#
lda (A3L),y is it a valid file# ?
beq badref must not be 0.
cmp #$09 must be 1 to 8 only.
bcs badref
pha
dec a
lsr a
ror a
ror a
ror a multiply by 32.
sta fcbptr used as an index to fcb
tay
pla restore ref# in acc
cmp fcbbuf,y
bne errnoref
fndfcbuf .EQ *-ofsX get page address of file buffer.
lda fcbbuf+11,y
jsr getbufadr get file's address into bufaddrl,h
ldx bufaddrh (y=fcbptr preserved)
beq fcbdead fcb corrupted
stx datptr+1 save ptr to data area of buffer
inx
inx index block always 2 pages after data
stx zpt+1
lda fcbbuf+1,y also set up device #
sta devnum
lda bufaddrl
sta datptr index and data buffers always on
sta zpt page boundaries.
fndfvol tax search for associated vcb
lda vcbbuf+16,x
cmp fcbbuf+1,y is this vcb the same device?
beq tstvopen if it is, make sure volume is active.
nxtfvol txa adjust index to next vcb.
clc
adc #$20
bcc fndfvol loop until volume found.
lda #$0A open file has no volume so
jsr sysdeath kill the system.
fcbdead lda #$0B fcb error so
jsr sysdeath kill the system.
tstvopen lda vcbbuf,x make sure this vcb is open.
beq nxtfvol branch if it is not active.
stx vcbptr save ptr to good vcb.
clc no error
rts
errnoref lda #$00 put a zero into this fcb to
sta fcbbuf,y show free fcb.
badref lda #$43 requested refnum is
sec illegal (out of range)
rts
* online command
online .EQ *-ofsX move user spec'd buffer ptr to usrbuf.
jsr mvdbufr figure out how big buffer has to be.
stz cbytes set this for valdbuf routine.
stz cbytes+1
ldy #$01
lda (A3L),y if 0 then cbytes=$100 else $010 for one
and #$F0 device. mask out unused nibble.
sta devnum last device used.
beq H343C branch if all devices.
lda #$10 cbytes = $010
sta cbytes
bne H343F always taken
H343C inc cbytes+1 cbytes = $100
H343F jsr valdbuf go validate buffer range against
bcs onlinerr allocated memory.
lda #$00 zero out user buffer space
ldy cbytes
H3449 dey
sta (usrbuf),y
bne H3449
sta namptr used as pointer to user buffer.
lda devnum get device # again.
bne H3474 branch if only 1 device to process.
jsr mvdevnums get list of currently recognized dev's.
H3459 phx save index to last item on list
lda loklst,x
sta devnum save desired device to look at.
jsr online1 log this volume and return it's name.
lda namptr inc pointer for next device
clc
adc #$10
sta namptr
plx get index to device list.
dex next device.
bpl H3459 branch if there is another device.
lda #$00 no errors for multiple on-line
clc
onlinerr rts
online1 .EQ *-ofsX
H3474 jsr fnddvcb see if it has already been logged in.
bcs olinerr1 branch if vcb is full.
ldx #$00 read in root (volume) directory
lda #$02
jsr rdblk read it into general purpose buffer.
ldx vcbptr index to the vcb entry.
bcc volfound branch if read was ok.
tay error value.
lda vcbbuf+17,x don't take the vcb offline if
bne rtrnerr there are active files present.
sta vcbbuf,x now take the volume offline
sta vcbbuf+16,x
rtrnerr tya error value.
bcs olinerr1 branch if unable to read.
volfound lda vcbbuf,x has it been logged in before?
beq H349E if not.
lda vcbbuf+17,x it has, are there active files?
bmi H34AA branch if volume is currently busy.
H349E jsr logvcb1 go log it in.
bcs olinerr1 branch if there is a problem.
lda #$57 anticipate a duplicate active volume
bit duplflag exits.
bmi olinerr1 branch if so.
H34AA ldx vcbptr
jsr cmpvcb does vol read compare with logged vol?
lda #$2E anticipate wrong volume mounted.
bcc H34D0 branch if ok.
olinerr1 pha save error code.
jsr svdevn report what device has problem.
pla error code.
iny tell what error was encountered.
sta (usrbuf),y
cmp #$57 duplicate volume error?
bne H34CE no.
iny report which other device has same name
ldx vcbentry
lda vcbbuf+16,x
sta (usrbuf),y
stz duplflag clear duplicate flag.
lda #$57 duplicate volume error code.
H34CE sec flag error
rts
H34D0 lda vcbbuf,x get volume name count
sta namcnt
ldy namptr index to user's buffer.
H34D9 lda vcbbuf,x move name to user's buffer
sta (usrbuf),y
inx
iny
dec namcnt
bpl H34D9
svdevn .EQ *-ofsX
ldy namptr index to 1st byte of this entry.
lda devnum upper nibble = device# and
ora (usrbuf),y lower nibble = name length.
sta (usrbuf),y
clc no errors
rts end of block file manager
* create file
create .EQ *-ofsX
jsr lookfile check for duplicate, get free entry
bcs tstfnf error code may be 'file not found'
lda #$47 name already exists
crerr1 sec
rts
tstfnf cmp #$46 'file not found' is ok
bne crerr1 otherwise exit with error.
ldy #$07 test for tree or directory file,
lda (A3L),y no other kinds are legal.
cmp #$04 is it seed, sapling or tree?
bcc tstdspc branch if it is
cmp #$0D
bne ctyperr report type error if not directory.
tstdspc lda devnum make sure destination device
jsr twrprot1 is not write protected.
bcs H351D
lda nofree is there space in directory to
beq xtndir add this file? branch if not
jmp creat1 otherwise, go create file.
ctyperr lda #$4B filetype error
sec
H351D rts
xtndir lda own_blk before extending directory,
ora own_blk+1 make sure it's a subdirectory.
bne H352A
lda #$49 otherwise, directory full error
sec
rts
H352A lda bloknml preserve disk address of current (last)
pha directory link, before allocating an
lda bloknml+1 extended block.
pha
jsr alc1blk allocate a block for extending directory
plx
stx bloknml+1 restore block addr of dir info in gbuf
plx
stx bloknml
bcs H351D unable to allocate.
sta gbuf+2 save block address in y,a to
sty gbuf+3 current directory.
jsr wrtgbuf update directory block with new link.
bcs H351D if error
ldx #$01
swpbloks lda bloknml,x prepare new directory block
sta gbuf,x using current block as back link
lda gbuf+2,x
sta bloknml,x and save new block as next to be written
dex
bpl swpbloks
inx
txa x and a = 0
clrdir sta gbuf+2,x
sta gbuf+$100,x
inx
bne clrdir
jsr wrtgbuf write prepared directory extension.
bcs H351D if error
lda own_blk
ldx own_blk+1
jsr rdblk read in parent directory block
ldx own_ent and calc entry address.
lda #>gbuf
sta zpt+1
lda #$04
ocalc clc
dex has entry address been calulated?
beq H3584 if yes.
adc own_len next entry address
bcc ocalc
inc zpt+1 entry must be in 2nd 256 bytes of block
bcs ocalc always taken.
H3584 sta zpt
ldy #$13 index to block count
H3588 lda (zpt),y
adc dinctbl-$13,y add 1 to block count and
sta (zpt),y
iny
tya $200 to the directory's eof.
eor #$18 done with usage/eof update?
bne H3588 branch if not.
jsr wrtgbuf go update parent.
bcs crerr2
jmp create
crerr2 rts return and report errors
creat1 .EQ *-ofsX
ldx #$00 zero out gbuf
H35A0 stz gbuf,x
stz gbuf+$100,x and data block of file.
inx
bne H35A0
ldy #$0B move user specified date/time
cmvtime lda (A3L),y to directory.
sta d_filid,y
txa if all 4 bytes of date/time = 0
ora (A3L),y then use built-in date/time.
tax
dey
cpy #$07
bne cmvtime
txa does user want default time?
bne cmvname if not.
ldx #$03
mvdftime lda p8date,x move current default date/time
sta d_credt,x
dex
bpl mvdftime
cmvname lda (A3L),y y = index to file kind.
cmp #$04
lda #$10 assume tree type
bcc csvfkind
lda #$D0 it's directory.
csvfkind ldx namptr index to local name of pathname.
ora pathbuf,x combine file kind with name length.
sta d_stor sos calls this 'storage type'.
and #$0F strip back to name length
tay and use as counter for move.
clc
adc namptr calc end of name
tax
crname lda pathbuf,x move local name as filename
sta d_stor,y
dex
dey
bne crname
ldy #$03 index to 'access' parameter
lda (A3L),y
sta d_attr
iny also move 'file identification'
lda (A3L),y
sta d_filid
cmvauxid iny move auxillary identification bytes
lda (A3L),y
sta d_auxid-5,y
cpy #$06
bne cmvauxid
lda xdosver save current xdos version #
sta d_sosver
lda compat and backward compatibility #
sta d_comp
lda #$01 usage is always 1 block
sta d_usage
lda d_head place back pointer to header block
sta d_dhdr
lda d_head+1
sta d_dhdr+1
lda d_stor storage type.
and #$E0 is it a directory?
beq cralcblk branch if seed file.
ldx #$1E move header to data block
cmvheadr lda d_stor,x
sta gbuf+4,x
dex
bpl cmvheadr
eor #$30
sta gbuf+4 make it a directory header mark.
ldx #$07 overwrite password area and other
cmvpass lda pass,x header info.
sta gbuf+20,x
lda xdosver,x
sta gbuf+32,x
dex
bpl cmvpass
ldx #$02 and include info about parent directory
stx d_eof+1
cmvparnt lda d_entblk,x
sta gbuf+39,x
dex
bpl cmvparnt
lda h_entln lastly, the length of parent's
sta gbuf+42 directory entries.
cralcblk jsr alc1blk get address of file's data block
bcs crerr3
sta d_frst
sty d_frst+1
sta bloknml
sty bloknml+1
jsr wrtgbuf go write data block of file
bcs crerr3
inc h_fcnt add 1 to total # of files in this dir
bne credone
inc h_fcnt+1
credone jsr drevise go revise directories with new file
bcs crerr3
jmp upbmap lastly, update volume bitmap
entcalc .EQ *-ofsX
lda #>gbuf set high address of dir entry
sta zpt+1 index pointer.
lda #$04 calc address of entry based
ldx d_entnum on the entry #.
H3689 clc
H368A dex addr = gbuf + ((d_entnum-1) * h_entln)
beq H3696 branch with carry clear = no errors.
adc h_entln
bcc H368A
inc zpt+1 inc hi address.
bcs H3689 always.
H3696 sta zpt newly calculated low address.
crerr3 rts carry set if error.
drevise .EQ *-ofsX
lda p8date
beq H36A9 if no clock, then don't mod date/time.
ldx #$03
modtime lda p8date,x move last modification date/time
sta d_moddt,x to entry being updated.
dex
bpl modtime
drevise1 .EQ *-ofsX
H36A9 lda d_attr mark entry as backupable
ora bkbitflg (bit 5 = backup needed)
sta d_attr
lda d_dev get device # of directory
sta devnum to be revised
lda d_entblk and address of direcotry block.
ldx d_entblk+1
jsr rdblk read block into general purpose buffer
bcs crerr3
jsr entcalc fix up ptr to entry location within gbuf.
ldy h_entln now move 'd.' info to directory.
dey
H36CA lda d_stor,y
sta (zpt),y
dey
bpl H36CA
lda d_head is the entry block same as
cmp bloknml the entry's header block?
bne H36E0 if no, go save entry block
lda d_head+1 then maybe, so test high addresses.
cmp bloknml+1
beq uphead branch if they are the same block.
H36E0 jsr wrtgbuf go write updated directory block.
bcs crerr3
lda d_head get address of header block and
ldx d_head+1
jsr rdblk go read in header block to modify.
bcs crerr3
uphead ldy #$01 update current # of files in this dir.
H36F2 lda h_fcnt,y
sta gbuf+37,y (current entry count)
dey
bpl H36F2
lda h_attr also update header's attributes.
sta gbuf+34
jsr wrtgbuf go write updated header
bcs H375A
ripple lda gbuf+4 test for 'root' directory because
and #$F0 if it is, then directory revision
eor #$F0 is complete (leaves carry clear).
beq H3770 branch if done.
lda gbuf+41 get entry #
sta d_entnum
lda gbuf+42 and the length of ertries in that dir
sta h_entln
lda gbuf+39 get addr of parent entry's dir block
ldx gbuf+40
jsr rdblk read it
bcs H375A
jsr entcalc get indirect ptr to parent entry in gbuf
lda p8date don't touch mod
beq H373B if no clock...
ldx #$03 update the modification date & time
ldy #$24 for this entry too
H3732 lda p8date,x
sta (zpt),y
dey
dex
bpl H3732
H373B jsr wrtgbuf write updated entry back to disk.
bcs H375A if error.
ldy #$25 compare current block # to this
lda (zpt),y entry's header block.
iny
cmp bloknml are low addresses the same?
sta bloknml
bne H3751 branch if entry doesn't reside in same
lda (zpt),y block as header.
cmp bloknml+1 are high address the same?
beq ripple they are the same, continue to root dir.
H3751 lda (zpt),y not same so read in this dir's header.
sta bloknml+1
jsr rdgbuf
bcc ripple continue if read was good
H375A rts
tsterr lda #$52 not tree or dir, unrecognized type
sec
rts
tstsos .EQ *-ofsX test if xdos disk.
lda gbuf pointer to previous dir block
ora gbuf+1 must be null
bne tsterr
lda gbuf+4 test for header
and #$E0
cmp #$E0
bne tsterr
H3770 clc no error
rts
findfile .EQ *-ofsX
jsr lookfile see if file exists
bcs nofind
moventry .EQ *-ofsX
ldy h_entln
H377A lda (zpt),y move entry into storage
sta d_stor,y
dey
bpl H377A
lda #$00 no errors
nofind rts
lookfile .EQ *-ofsX
jsr preproot go find volume
bcs fnderr
bne L37C5 branch if more than root
lda #>gbuf otherwise, report a bad path error
sta zpt+1 (but 1st create a phantom entry
lda #$04 for open)
sta zpt
ldy #$1F move in id and date info
phantm1 lda (zpt),y
sta d_stor,y
dey
cpy #$17
bne phantm1
phantm2 lda rootstuf-$10,y
sta d_stor,y
dey
cpy #$0F
bne phantm2
lda #$D0 fake directory file
sta d_stor
lda gbuf+2 check forward link.
ora gbuf+3 if non-zero, assume full sized directory
bne H37C2 else assume it's the slot 3 /RAM volume
lda #$02 so reset eof and blocks_used fields
sta d_eof+1
lda #$01
sta d_usage
H37C2 lda #$40 bad path (carry set)
rts
lookfil0 .EQ *-ofsX
L37C5 stz nofree reset free entry indicator.
sec dir to be searched has header in this block.
L37C9 stz totent reset entry counter.
jsr looknam look for name pointed to by pnptr.
bcc namfound if name was found.
lda entcntl have we looked at all of the
sbc totent entries in this directory?
bcc L37E2 maybe, check hi count.
bne L37EB no, read next directory block.
cmp entcnth has the last entry been looked at?
beq errfnf yes, give 'file not found' error
bne L37EB or branch always.
L37E2 dec entcnth should be at least one
bpl L37EB so this should be branch always...
errdir lda #$51 directory error
fnderr sec
rts
L37EB sta entcntl keep a running count.
lda #>gbuf reset indirect pointer
sta zpt+1
lda gbuf+2 get link to next dir block
bne L37FC (if there is one).
cmp gbuf+3 are both zero, i.e. no link? if so,
beq errdir then not all entries were acct'd for.
L37FC ldx gbuf+3 acc has value for block# (low).
jsr rdblk go read the next linked directory.
bcc L37C9 if no error.
rts return error in acc.
errfnf lda nofree was any free entry found?
bne fnf0
lda gbuf+2 test link
bne L3814
cmp gbuf+3 if both are 0 then give up.
beq fnf0 report 'not found'.
L3814 sta d_entblk
lda gbuf+3
sta d_entblk+1 assume 1st entry of next block
lda #$01 is free for use.
sta d_entnum mark as valid (for create)
sta nofree
fnf0 jsr nxtpnam1 'file not found' or 'path not found'?
errpath1 sec if non-zero then 'path not found'
beq fnf1
lda #$44 path not found
rts
fnf1 lda #$46 file not found
rts
namfound jsr nxtpname adj index to next name in path.
beq filfound branch if that was the last name.
ldy #$00 be sure this is a directory entry.
lda (zpt),y high nibble will tell.
and #$F0
cmp #$D0 is it a subdirectory?
bne errpath1 error if not.
ldy #$11 get address of 1st subdirectory block
lda (zpt),y
sta bloknml (no checking done for a valid block#)
iny
sta d_head save as file's header block too
lda (zpt),y
sta bloknml+1
sta d_head+1
jsr rdgbuf read subdirectory into gbuf.
bcs fnderr1 if error.
lda gbuf+37 get the # of files contained in this
sta entcntl directory.
lda gbuf+38
sta entcnth
lda gbuf+20 make sure password is disabled
ldx #$00
sec
rol a
L3869 bcc L386C
inx
L386C asl
bne L3869
cpx #$05 is password disabled?
beq movhead
lda #$4A directory is not compatible
fnderr1 sec
rts
movhead jsr movhed0 move directory info.
jmp lookfil0 do next local pathname.
movhed0 .EQ *-ofsX
ldx #$0A move this directory info
L387F lda gbuf+28,x
sta h_credt,x
dex
bpl L387F
lda gbuf+4 if this is root, then nothing to do
and #$F0
eor #$F0 test header type.
beq L389C branch if root
ldx #$03 otherwise, save owner info about
L3893 lda gbuf+39,x this header.
sta own_blk,x
dex
bpl L3893
L389C rts
entadr .EQ *-ofsX
filfound lda h_maxent figure out which entry # this is
sec
sbc cntent max entries - count entries + 1
adc #$00 = entry # (carry was set)
sta d_entnum
lda bloknml and indicate block # of this directory
sta d_entblk
lda bloknml+1
sta d_entblk+1
clc
rts
looknam .EQ *-ofsX reset count of files per block
lda h_maxent
sta cntent
lda #>gbuf
sta zpt+1
lda #$04
L38C1 sta zpt reset indirect pointer to gbuf
bcs L38F8 branch if this block contains a header
ldy #$00
lda (zpt),y get length of name in directory.
bne isname branch if there is a name.
lda nofree test if a free entry has been declared.
bne L38F8 yes, inc to next entry.
jsr entadr set address for current entry.
inc nofree indicate a free spot has been found.
bne L38F8 always.
isname and #$0F strip byte (is checked by 'filfound')
inc totent inc count of valid files found.
sta namcnt save name length as counter.
ldx namptr get index to current path.
cmp pathbuf,x are both names the same length?
bne L38F8 no, inc to next entry.
cmpname inx (first) next letter index
iny
lda (zpt),y compare names letter by letter
cmp pathbuf,x
bne L38F8
dec namcnt all letters compared?
bne cmpname no, continue.
clc a match is found.
noname rts
L38F8 dec cntent checked all entries in this block?
sec
beq noname yes, no name match.
lda h_entln add entry length to current pointer
clc
adc zpt
bcc L38C1 branch if still in 1st page.
inc zpt+1 look on 2nd page.
clc carry should always be clear before
bcc L38C1 looking at next.
preproot .EQ *-ofsX
jsr findvol search vcb's and dev's for spec'd volume
bcs novolume
lda #$00 zero out directory temps
ldy #$42
L3914 sta own_blk,y and owner info
dey
bpl L3914
lda devnum setup device # for this directory
sta d_dev
jsr movhed0 setup other header info from directory
ldy #$01 in gbuf and clean up misc info.
ldx vcbptr
inx
L3929 lda vcbbuf+18,x misc info includes
sta h_tblk,y total # of blocks,
lda vcbbuf+26,x the address of the 1st bitmap,
sta h_bmap,y
lda |bloknml,y directory's disk address,
sta d_head,y
lda h_fcnt,y and setting up a counter for the # of
sta entcntl,y files in this directory.
dex
dey
bpl L3929
nxtpname .EQ *-ofsX
jsr nxtpnam1 get new namptr in y and namlen in acc.
sty namptr save new pathname pointer.
rts (status reg according to accumulator)
nxtpnam1 .EQ *-ofsX
ldy namptr inc pathname pointer to next name
lda pathbuf,y in the path.
sec
adc namptr if this addition results in zero,
tay then prefixed directory has been moved
bne L395F to another device. branch if not.
lda devnum revise devnum for prefixed directory
sta p_dev
L395F lda pathbuf,y test for end of name.
clc no errors
novolume rts
findvol .EQ *-ofsX
lda #$00
ldy preflag use prefix volume name to look up vcb.
bit prfxflg is this a prefixed path?
bpl L396F branch if it is
tay set ptr to volume name
L396F sty vnptr and save.
sta devnum zero out dev# until vcb located.
L3975 pha acc now used as vcb lookup index.
tax index pointer to x.
lda vcbbuf,x get vcb volume name length.
bne L3987 branch if claimed vcb to be tested.
L397C ldy vnptr restore pointer to requested vol name.
pla now adj vcb index to next vcb entry.
clc
adc #$20
bcc L3975 branch if more vcb's to check
bcs L39D4 otherwise go look for unlogged volumes.
L3987 sta namcnt save length of vol name to be compared.
L398A cmp pathbuf,y is it the same as requested vol name?
bne L397C branch if not
inx
iny next character
lda vcbbuf,x
dec namcnt last character?
bpl L398A if not.
plx restore pointer to matching vcb.
stx vcbptr save it for future reference.
lda vcbbuf+16,x get it's device #
sta devnum and save it.
stz bloknml+1 assume prefix is not used and
lda #$02 that root directory is to be used.
sta bloknml
lda vnptr = 0 if no prefix.
L39AC tay if prefix then find ptr to prefixed
sta namptr dir name. save path ptr.
beq L39C2 branch if no prefix.
sec
adc pathbuf,y inc to next dir in prefix path.
bcc L39AC branch if another dir in prefix.
lda p_blok volume verification will occur at
sta bloknml subdirectory level.
lda p_blok+1
sta bloknml+1
* verify volume name
L39C2 jsr rdgbuf read in directory (or prefix dir)
bcs L39CC if error then look on other devices.
jsr cmppnam compare dir name with path name.
bcc L39F0 if they match, stop looking.
L39CC ldx vcbptr check if current (matched) vcb is active
lda vcbbuf+17,x i.e. does it have open files?
bmi L39ED report not found if active.
L39D4 lda vnptr make path ptr same as volume ptr
sta namptr
jsr mvdevnums copy all device #'s to be examined.
lda devnum log current device 1st before searching
bne L39F1 others.
L39E2 ldx numdevs scan look list for devices we need
L39E5 lda loklst,x to search for the requested volume.
bne L39F4 branch if we've a device to look at.
dex
bpl L39E5 look at next one.
L39ED lda #$45 no mounted volume
sec error
L39F0 rts
L39F1 ldx numdevs now remove the device from the list
L39F4 cmp loklst,x of prospective devices.
beq L39FE branch if match.
dex look until found.
bpl L39F4 always taken (usually) unless
bmi L39ED if dev was removed from devlst (/RAM).
L39FE sta devnum preserve device to be checked next.
stz loklst,x mark this one as tested.
jsr fnddvcb find vcb that claims this dev (if any).
bcs L3A29 branch if vcb full.
ldx vcbptr did fndvcb find it or return free vcb?
lda vcbbuf,x
beq L3A16 if free vcb.
lda vcbbuf+17,x is this volume active?
bmi L39E2 if so, no need to re-log.
L3A16 lda #$02 go read root dir into gbuf
ldx #$00
jsr rdblk
bcs L39E2 ignore if unable to read.
jsr logvcb go log in volume name.
bcs L39E2 look at next if non-xdos disk mounted.
jsr cmppnam is this the volume ?
bcs L39E2 if not
L3A29 rts
mvdevnums .EQ *-ofsX
ldx numdevs copy all dev #'s to be checked.
L3A2D lda devlist,x active device list.
and #$F0 strip device type info.
sta loklst,x copy them to a temp workspace
dex
bpl L3A2D
ldx numdevs
rts
fnddvcb .EQ *-ofsX look for vcb with this device#
lda #$00
ldy #$FF
L3A40 tax new index to next vcb
lda vcbbuf+16,x check all devnums
cmp devnum is this the vcb?
bne L3A4E if not
stx vcbptr
clc indicates found
rts
L3A4E lda vcbbuf,x is this a free vcb?
bne L3A57 if not
iny
stx vcbptr
L3A57 txa
clc inc index to next vcb
adc #$20
bne L3A40
tya any free vcb's available?
bpl L3A79 yes
lda #$00 look for an entry to kick out
L3A62 tax
lda vcbbuf+17,x any open files?
bpl L3A70 no, kick this one out.
txa next vcb
clc
adc #$20 (vcb entry size)
bne L3A62
beq L3A7A all vcb entries have open files
L3A70 stx vcbptr save entry index.
stz vcbbuf,x free this entry
stz vcbbuf+16,x
L3A79 clc no error.
L3A7A lda #$55 # vcb full error
rts
cmppnam .EQ *-ofsX
ldx #$00 index to directory name.
ldy namptr index to pathname.
lda gbuf+4 get dir name length and type.
cmp #$E0 is it a directory?
bcc L3A90 if not.
and #$0F isolate name length and
sta namcnt save as a counter.
bne L3A95 branch if valid length.
L3A90 sec indicate not found
rts
L3A92 lda gbuf+4,x next char
L3A95 cmp pathbuf,y
bne L3A90 if not the same.
inx check next char
iny
dec namcnt
bpl L3A92 if more to compare.
clc match found
rts
logvcb .EQ *-ofsX
ldx vcbptr previously logged in volume?
lda vcbbuf,x (acc = 0?)
beq L3AB0 no, go prepare vcb.
jsr cmpvcb does vcb match vol read?
bcc L3B05 yes, do not disturb.
logvcb1 .EQ *-ofsX
L3AB0 ldy #$1F zero out vcb entry
L3AB2 stz vcbbuf,x
inx
dey
bpl L3AB2
jsr tstsos make sure it's an xdos disk
bcs L3B05 if not, return carry set.
jsr tstdupvol does a duplicate with open files
bcs L3B04 already exist? branch if yes.
lda gbuf+4 move volume name to vcb.
and #$0F strip root marker
tay
pha
ora vcbptr
tax
L3ACE lda gbuf+4,y
sta vcbbuf,x
dex
dey
bne L3ACE
pla get length again
sta vcbbuf,x and save.
lda devnum last device used.
sta vcbbuf+16,x save device # and
lda gbuf+41 total # of blocks on this unit.
sta vcbbuf+18,x
lda gbuf+42
sta vcbbuf+19,x
lda bloknml save address of root directory.
sta vcbbuf+22,x
lda bloknml+1
sta vcbbuf+23,x
lda gbuf+39 save address of the 1st bitmap.
sta vcbbuf+26,x
lda gbuf+40
sta vcbbuf+27,x
L3B04 clc indicate logged if possible
L3B05 rts
cmpvcb .EQ *-ofsX compare volume name in vcb
lda gbuf+4 with name in directory.
and #$0F
cmp vcbbuf,x are they the same length?
stx xvcbptr (see rev note #23)
bne L3B1E if not the same.
tay
ora xvcbptr
tax
L3B18 lda gbuf+4,y
cmp vcbbuf,x
L3B1E sec anticipate different names.
bne L3B26 if not the same.
dex
dey
bne L3B18
clc indicate match.
L3B26 ldx xvcbptr offset to start of vcb (rev note #23)
rts
tstdupvol .EQ *-ofsX check for other logged in volumes
lda #$00 with the same name.
L3B2C tax
jsr cmpvcb
bcs L3B41 if no match.
lda vcbbuf+17,x test for any open files.
bmi L3B4B cannot look at this volume.
lda #$00 take duplicate offline if no open files
sta vcbbuf,x
sta vcbbuf+16,x
beq L3B49 ok to log in new volume.
L3B41 txa index to next vcb
clc
and #$E0 strip odd stuff.
adc #$20 inc to next entry.
bcc L3B2C branch if more to check
L3B49 clc
rts
L3B4B sta duplflag duplicate has been found.
stx vcbentry save pointer to conflicting vcb.
sec error.
rts
tstfrblk .EQ *-ofsX test if enough free blocks available
ldx vcbptr for request.
lda vcbbuf+21,x check if proper count for this volume.
ora vcbbuf+20,x
bne L3BAD branch if count is non-zero.
tkfrecnt .EQ *-ofsX
jsr cntbms get # of bitmaps
sta bmcnt and save.
stz scrtch start count at 0
stz scrtch+1
lda #$FF mark 'first free' temp as unknown
sta nofree
jsr upbmap update volume bitmap.
bcs L3BC1 if error.
ldx vcbptr get address of 1st bitmap
lda vcbbuf+26,x
sta bloknml
lda vcbbuf+27,x
sta bloknml+1
L3B81 jsr rdgbuf use general buffer for temp space to
bcs L3BC1 count free blocks (bits).
jsr count
dec bmcnt was that the last bitmap?
bmi L3B96 if so, go change fcb so not done again.
inc bloknml
bne L3B81
inc bloknml+1
bra L3B81
L3B96 ldx vcbptr mark which block had 1st free space
lda nofree
bmi L3BBE if no free space was found.
sta vcbbuf+28,x update the free count.
lda scrtch+1
sta vcbbuf+21,x update volume control byte.
lda scrtch
sta vcbbuf+20,x
L3BAD lda vcbbuf+20,x compare total available free blocks
sec on this volume.
sbc reql
lda vcbbuf+21,x
sbc reqh
bcc L3BBE
clc
rts
L3BBE lda #$48 disk full
sec
L3BC1 rts
count .EQ *-ofsX
ldy #$00
L3BC4 lda gbuf,y bit pattern.
beq L3BCC don't count
jsr cntfree
L3BCC lda gbuf+$100,y do both pages with same loop
beq L3BD4
jsr cntfree
L3BD4 iny
bne L3BC4 loop until all 512 bytes counted.
bit nofree has 1st block w/free space been found?
bpl L3BEE if yes.
lda scrtch test to see if any blocks were counted
ora scrtch+1
beq L3BEE branch if none counted.
jsr cntbms get total # of maps.
sec subtract countdown from total bitmaps
sbc bmcnt
sta nofree
L3BEE rts
cntfree .EQ *-ofsX
L3BEF asl count the # of bits in this byte
bcc L3BFA
inc scrtch
bne L3BFA
inc scrtch+1
L3BFA ora #$00
bne L3BEF loop until all bits counted
rts
cntbms .EQ *-ofsX
ldx vcbptr
ldy vcbbuf+19,x return the # of bitmaps
lda vcbbuf+18,x possible with the total count
bne L3C0B found in the vcb.
dey adj for bitmap block boundary
L3C0B tya
lsr a divide by 16. the result is
lsr a the # of bitmaps.
lsr a
lsr a
rts
* deallocate a block's entry in bitmap
* on entry, x,a = address of block
dealloc .EQ *-ofsX
stx bmcnt high address of block.
pha save low address.
ldx vcbptr check that bitmap block address is
lda vcbbuf+19,x valid given the total # of blocks
cmp bmcnt on the volume.
pla
bcc L3C8C branch if invalid
tax
and #$07 bit to be or'd in
tay
lda whichbit,y (shifting takes 7 bytes, but is slower)
sta nofree save bit pattern.
txa low block address.
lsr bmcnt
ror a get pointer to byte in block that
lsr bmcnt represents the block address.
ror a
lsr bmcnt
ror a
sta bmptr save pointer.
lsr bmcnt transfer bit which is page of bitmap
rol half
jsr fndbmap make sure device is correct one.
bcs L3C8B error.
lda bmacmap current map.
cmp bmcnt is in-core bitmap the correct one ?
beq L3C64 branch if yes.
jsr upbmap put current map away.
bcs L3C8B error.
lda bmcnt get map #
ldx vcbptr
sta vcbbuf+28,x and make it current.
lda bmadev
jsr gtbmap read it into buffer
bcs L3C8B
L3C64 ldy bmptr index to byte
lsr half
lda nofree (get indiviual bit)
bcc L3C77 branch if on page 1 of bitmap
ora bmbuf+$100,y
sta bmbuf+$100,y
bcs L3C7D always.
bmbufhi .EQ *-ofsX this address + 2 is used as an
L3C77 ora bmbuf,y absolute reference to bmbuf high byte.
sta bmbuf,y
L3C7D lda #$80 mark bitmap as modified
tsb bmastat
inc deblock inc count of blocks deallocated
bne L3C8A
inc deblock+1
L3C8A clc
L3C8B rts
L3C8C lda #$5A bitmap block # impossible.
sec bitmap disk address wrong
rts (maybe data masquerading as indx block)
alc1blk .EQ *-ofsX
jsr fndbmap get address of bitmap.
bcs L3CB8 error.
L3C95 ldy #$00 begin search at start of bitmap block.
sty half which half (page) to search
L3C9A lda bmbuf,y
bne L3CB9 free blocks indicated by 'on' bits
iny
bne L3C9A check all in 1st page.
inc half now search page 2.
inc basval base value = base address / 2048.
L3CA8 lda bmbuf+$100,y search 2nd half for free block
bne L3CB9
iny
bne L3CA8
inc basval add 2048 offset for next page.
jsr nxtbmap get next bitmap (if exists) and
bcc L3C95 update vcb. branch if no error.
L3CB8 rts return error.
L3CB9 sty bmptr save index pointer to valid bit group.
lda basval prep for block address calculation
sta scrtch+1
tya address of bit pattern.
asl multiply this and basval by 8
rol scrtch+1
asl
rol scrtch+1
asl
rol scrtch+1
tax low address within 7 of actual address
sec
lda half
beq L3CDB branch if allocating from 1st half.
lda bmbuf+$100,y get pattern from 2nd page.
bcs L3CDE always.
L3CDB lda bmbuf,y get bit pattern from 1st page.
L3CDE rol a find left most 'on' bit
bcs L3CE4 if found.
inx adjust low address.
bne L3CDE always.
L3CE4 lsr a restore pos'n of all but left most bit.
bcc L3CE4 loop until mark moves into carry.
stx scrtch save low address.
ldx half which half of bitmap ?
bne L3CF4 if page 2.
sta bmbuf,y
beq L3CF7 always.
L3CF4 sta bmbuf+$100,y update to show allocated block in use.
L3CF7 lda #$80 indicate map is modified.
tsb bmastat
ldy vcbptr subtract 1 from total free vcb blocks
lda vcbbuf+20,y to account for newly allocated block.
sbc #$01 (carry is set)
sta vcbbuf+20,y
bcs L3D10 if high free count doesn't need adj.
lda vcbbuf+21,y adjust high count
dec a
sta vcbbuf+21,y
L3D10 clc no errors.
lda scrtch return address in y,a of newly
ldy scrtch+1 allocated block.
rts
nxtbmap .EQ *-ofsX inc to next bitmap
ldy vcbptr but 1st make sure there is another one.
lda vcbbuf+19,y
lsr a
lsr a
lsr a
lsr a
cmp vcbbuf+28,y are there more maps ?
beq L3D60 if no more to look at.
lda vcbbuf+28,y add 1 to current map
inc
sta vcbbuf+28,y
jsr upbmap
fndbmap .EQ *-ofsX
ldy vcbptr
lda vcbbuf+16,y get device #.
cmp bmadev does this map match this device ?
beq L3D4A yes.
jsr upbmap otherwise, save other volume's bitmap
bcs L3D5F
ldy vcbptr
lda vcbbuf+16,y
sta bmadev and read in fresh bitmap for this dev.
L3D4A ldy bmastat is it already modified ?
bmi L3D54 yes, return pointer
jsr gtbmap otherwise read in fresh bitmap.
bcs L3D5F if error.
L3D54 ldy vcbptr get relative block # of bitmap.
lda vcbbuf+28,y
asl 2 pages per block
sta basval
clc no errors.
L3D5F rts
L3D60 lda #$48 request can't be filled
sec error
rts
upbmap .EQ *-ofsX
clc
lda bmastat is current map modified ?
bpl L3D5F no.
jsr wrtbmap update device.
bcs L3D5F if error on writing.
lda #$00
sta bmastat mark bitmap buffer as free
rts
gtbmap .EQ *-ofsX read bitmap specified by dev and vcb.
sta bmadev
ldy vcbptr get lowest map # with free blocks in it
lda vcbbuf+28,y
sta bmacmap associate offset with bitmap ctrl block.
clc add this # to the base address of
adc vcbbuf+26,y 1st bitmap and save in bmadadr which
sta bmadadr is address of bitmap to be used.
lda vcbbuf+27,y
adc #$00
sta bmadadr+1
lda #$01 read device command
L3D92 sta A4L
lda devnum save current dev #
pha
lda bmadev get bitmap's dev #
sta devnum
lda bmadadr and disk address
sta bloknml
lda bmadadr+1
sta bloknml+1
lda bmbufhi+2 address of the buffer (low = 0)
jsr dobitmap
tax error code (if any).
pla restore current dev #
sta devnum
bcc L3DB6 and return it if no error.
txa error code
L3DB6 rts
rdblk .EQ *-ofsX
sta bloknml
stx bloknml+1
jsr rdgbuf
rts
wrtbmap .EQ *-ofsX write bitmap.
lda #$02 write command.
bne L3D92 always.
wrtgbuf .EQ *-ofsX
lda #$02 write command
bne L3DC9 always.
rdgbuf .EQ *-ofsX
lda #$01 read command.
L3DC9 sta A4L pass to device handler.
lda #>gbuf general buffer.
dobitmap .EQ *-ofsX
php no interrupts
sei
sta buf+1 buffer high.
stz buf buffer low (always on page boundary)
stz p8error clear global error code.
lda #$FF indicates reg call made to dev handler
sta ioaccess
lda devnum transfer dev # for dispatcher to
sta unitnum convert to unit #.
jsr dmgr call the driver.
bcs L3DE8 if error.
plp restore interrupts.
clc
rts
L3DE8 plp file i/o error. restore interrupts.
sec
rts
*--------------------------------------
MAN
SAVE USR/SRC/PRODOS.203/PRODOS.S.XDOS
LOAD USR/SRC/PRODOS.203/PRODOS.S
ASM
Reference in New Issue View Git Blame Copy Permalink