prog8/compiler/res/prog8lib/cx16/diskio.p8

984 lines
33 KiB
Lua

; Commander X16 disk drive I/O routines.
; Largely compatible with the default C64 ones, but adds more stuff specific to the X16 as well.
; NOTE: If you experience weird behavior with these routines and you are using them
; in the X16 emulator using HostFs, please try again with an SD-card image instead first.
; It is possible that there are still small differences between HostFS and actual CBM DOS in the emulator.
;
; About the secondary addresses:
; for writes (new files or overwrites), you can use 1 (without the mode string) or 2-14 (with the mode string)
; for reads (existing files) you can use 0 or 2-14 (mode string is optional)
; for modify mode (new files* or existing files), you must use 2-14, and the mode string ,s,m is required
%import textio
%import conv
%import strings
%import syslib
diskio {
%option no_symbol_prefixing, ignore_unused
const ubyte READ_IO_CHANNEL=12
const ubyte WRITE_IO_CHANNEL=13
ubyte @shared drivenumber = 8 ; user programs can set this to the drive number they want to load/save to!
sub reset_read_channel() {
void cbm.CHKIN(READ_IO_CHANNEL)
}
sub reset_write_channel() {
cbm.CHKOUT(WRITE_IO_CHANNEL)
}
sub fastmode(ubyte mode) -> bool {
; -- set fast serial mode (0=none, 1=auto_tx, 2=fast writes, 3=both) for the SD card.
; Returns success status (fails on emulator host fs for example)
list_filename[0] = 'u'
list_filename[1] = '0'
list_filename[2] = '>'
list_filename[3] = 'b'
list_filename[4] = mode | $30
list_filename[5] = 0
send_command(list_filename)
return status_code()==0
}
sub directory() -> bool {
; -- Prints the directory contents to the screen. Returns success.
cbm.SETNAM(1, "$")
cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
ubyte status = 1
void cbm.OPEN() ; open 12,8,0,"$"
if_cs
goto io_error
reset_read_channel()
repeat 4 {
void cbm.CHRIN() ; skip the 4 prologue bytes
}
; while not stop key pressed / EOF encountered, read data.
status = cbm.READST()
if status!=0 {
status = 1
goto io_error
}
while status==0 {
ubyte low = cbm.CHRIN()
ubyte high = cbm.CHRIN()
txt.print_uw(mkword(high, low))
txt.spc()
ubyte @zp character
repeat {
character = cbm.CHRIN()
if character==0
break
txt.chrout(character)
}
txt.nl()
void cbm.CHRIN() ; skip 2 bytes
void cbm.CHRIN()
status = cbm.READST()
void cbm.STOP()
if_z
break
}
status = cbm.READST()
io_error:
cbm.CLRCHN() ; restore default i/o devices
cbm.CLOSE(READ_IO_CHANNEL)
if status!=0 and status & $40 == 0 { ; bit 6=end of file
txt.print("\ni/o error, status: ")
txt.print_ub(status)
txt.nl()
return false
}
return true
}
sub diskname() -> uword {
; returns disk label name or 0 if error
cbm.SETNAM(3, "$")
cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
ubyte status = 1
void cbm.OPEN() ; open 12,8,0,"$=c"
if_cs
goto io_error
reset_read_channel()
while cbm.CHRIN()!='"' {
; skip up to entry name
}
cx16.r0 = &list_filename
repeat {
@(cx16.r0) = cbm.CHRIN()
if @(cx16.r0)=='"' {
@(cx16.r0) = ' '
while @(cx16.r0)==' ' and cx16.r0>=&list_filename {
@(cx16.r0) = 0
cx16.r0--
}
break
}
cx16.r0++
}
status = cbm.READST()
io_error:
cbm.CLRCHN()
cbm.CLOSE(READ_IO_CHANNEL)
if status!=0 and status & $40 == 0
return 0
return list_filename
}
; internal variables for the iterative file lister / loader
bool list_skip_disk_name
uword list_pattern
uword list_blocks
bool iteration_in_progress = false
bool write_iteration_in_progress = false
str list_filetype = "???" ; prg, seq, dir
str list_filename = "?" * 50
; ----- get a list of files (uses iteration functions internally) -----
sub list_filenames(uword pattern_ptr, uword filenames_buffer, uword filenames_buf_size) -> ubyte {
; -- fill the provided buffer with the names of the files on the disk (until buffer is full).
; Files in the buffer are separated by a 0 byte. You can provide an optional pattern to match against.
; After the last filename one additional 0 byte is placed to indicate the end of the list.
; Returns number of files (it skips 'dir' entries i.e. subdirectories).
; Also sets carry on exit: Carry clear = all files returned, Carry set = directory has more files that didn't fit in the buffer.
uword buffer_start = filenames_buffer
ubyte files_found = 0
filenames_buffer[0]=0
if lf_start_list(pattern_ptr) {
while lf_next_entry() {
if list_filetype!="dir" {
filenames_buffer += strings.copy(list_filename, filenames_buffer) + 1
files_found++
if filenames_buffer - buffer_start > filenames_buf_size-20 {
@(filenames_buffer)=0
lf_end_list()
sys.set_carry()
return files_found
}
}
}
lf_end_list()
}
@(filenames_buffer)=0
sys.clear_carry()
return files_found
}
; ----- iterative file lister functions (uses the read io channel) -----
sub lf_start_list(uword pattern_ptr) -> bool {
; -- start an iterative file listing with optional pattern matching.
; note: only a single iteration loop can be active at a time!
lf_end_list()
list_pattern = pattern_ptr
list_skip_disk_name = true
iteration_in_progress = true
cbm.SETNAM(1, "$")
cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
void cbm.OPEN() ; open 12,8,0,"$"
if_cs
goto io_error
reset_read_channel()
repeat 4 {
void cbm.CHRIN() ; skip the 4 prologue bytes
}
if cbm.READST()==0
return true
io_error:
cbm.CLOSE(READ_IO_CHANNEL)
lf_end_list()
return false
}
sub lf_next_entry() -> bool {
; -- retrieve the next entry from an iterative file listing session.
; results will be found in list_blocks, list_filename, and list_filetype.
; if it returns false though, there are no more entries (or an error occurred).
if not iteration_in_progress
return false
repeat {
reset_read_channel() ; use the input io channel again
uword nameptr = &list_filename
ubyte blocks_lsb = cbm.CHRIN()
ubyte blocks_msb = cbm.CHRIN()
if cbm.READST()!=0
goto close_end
list_blocks = mkword(blocks_msb, blocks_lsb)
; read until the filename starts after the first "
while cbm.CHRIN()!='\"' {
if cbm.READST()!=0
goto close_end
}
; read the filename
repeat {
ubyte character = cbm.CHRIN()
if character==0
break
if character=='\"'
break
@(nameptr) = character
nameptr++
}
@(nameptr) = 0
do {
cx16.r15L = cbm.CHRIN()
} until cx16.r15L!=' ' ; skip blanks up to 3 chars entry type
list_filetype[0] = cx16.r15L
list_filetype[1] = cbm.CHRIN()
list_filetype[2] = cbm.CHRIN()
while cbm.CHRIN()!=0 {
; read the rest of the entry until the end
}
void cbm.CHRIN() ; skip 2 bytes
void cbm.CHRIN()
if not list_skip_disk_name {
if list_pattern==0
return true
if strings.pattern_match(list_filename, list_pattern)
return true
}
list_skip_disk_name = false
}
close_end:
lf_end_list()
return false
}
sub lf_end_list() {
; -- end an iterative file listing session (close channels).
if iteration_in_progress {
cbm.CLRCHN()
cbm.CLOSE(READ_IO_CHANNEL)
iteration_in_progress = false
}
}
; ----- iterative file loader functions (uses the read io channel) -----
sub f_open(str filenameptr) -> bool {
; -- open a file for iterative reading with f_read
; note: only a single iteration loop can be active at a time!
; Returns true if the file is successfully opened and readable.
; No need to check status(), unlike f_open_w() !
; NOTE: the default input isn't yet set to this logical file, you must use reset_read_channel() to do this,
; if you're going to read from it yourself instead of using f_read()!
f_close()
cbm.SETNAM(strings.length(filenameptr), filenameptr)
cbm.SETLFS(READ_IO_CHANNEL, drivenumber, READ_IO_CHANNEL) ; note: has to be Channel,x,Channel because otherwise f_seek doesn't work
void cbm.OPEN() ; open 12,8,12,"filename"
if_cc {
reset_read_channel()
if cbm.READST()==0 {
iteration_in_progress = true
void cbm.CHRIN() ; read first byte to test for file not found
if cbm.READST()==0 {
cbm.CLOSE(READ_IO_CHANNEL) ; close file because we already consumed first byte
void cbm.OPEN() ; re-open the file
cbm.CLRCHN() ; reset default i/o channels
return true
}
}
}
f_close()
cbm.CLOSE(READ_IO_CHANNEL)
return false
}
; optimized for Commander X16 to use MACPTR block read kernal call
sub f_read(uword bufferpointer, uword num_bytes) -> uword {
; -- read from the currently open file, up to the given number of bytes.
; returns the actual number of bytes read. (checks for End-of-file and error conditions)
; NOTE: cannot be used to load into VRAM. Use vload() or call cx16.MACPTR() yourself with the vera data register as address.
if not iteration_in_progress or num_bytes==0
return 0
reset_read_channel()
if num_bytes==1 {
; optimize for reading just a single byte
@(bufferpointer) = cbm.CHRIN()
cx16.r0L = cbm.READST()
if cx16.r0L!=0 {
f_close()
if cx16.r0L & $40 == 0
return 0
}
return 1
}
list_blocks = 0 ; we reuse this variable for the total number of bytes read
uword readsize
while num_bytes!=0 {
readsize = 255
if num_bytes<readsize
readsize = num_bytes
void, readsize = cx16.MACPTR(lsb(readsize), bufferpointer, false) ; fast block reads
if_cs
goto byte_read_loop ; MACPTR block read not supported, do fallback loop
list_blocks += readsize
bufferpointer += readsize
if msb(bufferpointer) == $c0
bufferpointer = mkword($a0, lsb(bufferpointer)) ; wrap over bank boundary
num_bytes -= readsize
if cbm.READST() & $40 !=0 {
f_close() ; end of file, close it
break
}
}
return list_blocks ; number of bytes read
byte_read_loop: ; fallback if MACPTR isn't supported on the device
%asm {{
lda bufferpointer
sta m_in_buffer+1
lda bufferpointer+1
sta m_in_buffer+2
}}
while num_bytes!=0 {
%asm {{
jsr cbm.CHRIN
m_in_buffer sta $ffff
inc m_in_buffer+1
bne +
inc m_in_buffer+2
+
}}
cx16.r0L = cbm.READST()
if cx16.r0L!=0 {
f_close()
if cx16.r0L & $40 !=0 ; eof?
return list_blocks ; number of bytes read
return 0 ; error.
}
list_blocks++
num_bytes--
}
return list_blocks ; number of bytes read
}
; optimized for Commander X16 to use MACPTR block read kernal call
sub f_read_all(uword bufferpointer) -> uword {
; -- read the full contents of the file, returns number of bytes read.
; It is assumed the file size is less than 64 K.
; NOTE: cannot be used to load into VRAM. Use vload() or call cx16.MACPTR() yourself with the vera data register as address.
if not iteration_in_progress
return 0
reset_read_channel()
uword total_read = 0
while cbm.READST()==0 {
cx16.r0 = f_read(bufferpointer, 256)
total_read += cx16.r0
bufferpointer += cx16.r0
}
return total_read
}
asmsub f_readline(uword bufptr @AY) clobbers(X) -> ubyte @Y, ubyte @A {
; Routine to read text lines from a text file. Lines must be less than 255 characters.
; Reads characters from the input file UNTIL a newline or return character (or EOF).
; The line read will be 0-terminated in the buffer (and not contain the end of line character).
; The length of the line is returned in Y. Note that an empty line is okay and is length 0!
; The I/O error status byte is returned in A.
%asm {{
sta P8ZP_SCRATCH_W1
sty P8ZP_SCRATCH_W1+1
jsr reset_read_channel
ldy #0
_loop jsr cbm.CHRIN
sta (P8ZP_SCRATCH_W1),y
beq _end
iny
cmp #$0a
beq _line_end
cmp #$0d
bne _loop
_line_end dey ; get rid of the trailing end-of-line char
lda #0
sta (P8ZP_SCRATCH_W1),y
_end jsr cbm.READST
rts
}}
}
sub f_close() {
; -- end an iterative file loading session (close channels).
; it is safe to call this multiple times, or when no file is open for reading.
if iteration_in_progress {
cbm.CLRCHN()
cbm.CLOSE(READ_IO_CHANNEL)
iteration_in_progress = false
}
}
; ----- iterative file writing functions (uses write io channel) -----
sub f_open_w(str filename) -> bool {
; -- Open a file for iterative writing with f_write
; WARNING: returns true if the open command was received by the device,
; but this can still mean the file wasn't successfully opened for writing!
; (for example, if it already exists). This is different than f_open()!
; To be 100% sure if this call was successful, you have to use status()
; and check the drive's status message!
return internal_f_open_w(filename, false)
}
sub f_open_w_seek(str filename) -> bool {
; -- Open an existing file for iterative writing with f_write, and seeking with f_seek_w.
return internal_f_open_w(filename, true)
}
sub internal_f_open_w(str filename, bool open_for_seeks) -> bool {
f_close_w()
list_filename = filename
str modifier = ",s,?"
modifier[3] = 'w'
if open_for_seeks
modifier[3] = 'm'
cx16.r0L = strings.append(list_filename, modifier) ; secondary 13 requires a mode suffix to signal we're writing/modifying
cbm.SETNAM(cx16.r0L, list_filename)
cbm.SETLFS(WRITE_IO_CHANNEL, drivenumber, WRITE_IO_CHANNEL)
void cbm.OPEN() ; open 13,8,13,"filename"
if_cc {
if cbm.READST()==0 {
write_iteration_in_progress = true
return true
}
}
cbm.CLOSE(WRITE_IO_CHANNEL)
f_close_w()
return false
}
sub f_write(uword bufferpointer, uword num_bytes) -> bool {
; -- write the given number of bytes to the currently open file
; you can call this multiple times to append more data
if num_bytes!=0 {
reset_write_channel()
do {
void, cx16.r0 = cx16.MCIOUT(lsb(num_bytes), bufferpointer, false) ; fast block writes
if_cs
goto no_mciout
num_bytes -= cx16.r0
bufferpointer += cx16.r0
if msb(bufferpointer) == $c0
bufferpointer = mkword($a0, lsb(bufferpointer)) ; wrap over bank boundary
if cbm.READST()!=0
return false
} until num_bytes==0
return cbm.READST()==0
no_mciout:
; the device doesn't support MCIOUT, use a normal per-byte write loop
repeat num_bytes {
cbm.CHROUT(@(bufferpointer))
bufferpointer++
}
return cbm.READST()==0
}
return true
}
sub f_close_w() {
; -- end an iterative file writing session (close channels).
; it is safe to call this multiple times, or when no file is open for reading.
if write_iteration_in_progress {
cbm.CLRCHN()
cbm.CLOSE(WRITE_IO_CHANNEL)
write_iteration_in_progress = false
}
}
; ---- other functions ----
sub status() -> uword {
; -- retrieve the disk drive's current status message
str device_not_present_error = "device not present #xx"
if cbm.READST()==128 {
device_not_present_error[len(device_not_present_error)-2] = 0
void strings.copy(conv.str_ub(drivenumber), &device_not_present_error+len(device_not_present_error)-2)
return device_not_present_error
}
uword messageptr = &list_filename
cbm.SETNAM(0, list_filename)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN() ; open 15,8,15
if_cs
goto io_error
void cbm.CHKIN(15) ; use #15 as input channel
while cbm.READST()==0 {
cx16.r5L = cbm.CHRIN()
if cx16.r5L=='\r' or cx16.r5L=='\n'
break
@(messageptr) = cx16.r5L
messageptr++
}
@(messageptr) = 0
done:
cbm.CLRCHN() ; restore default i/o devices
cbm.CLOSE(15)
return list_filename
io_error:
cbm.CLOSE(15)
list_filename = "io error"
goto done
}
; similar to above, but instead of fetching the entire string, it only fetches the status code and returns it as ubyte
; in case of IO error, returns 255 (CMDR-DOS itself is physically unable to return such a value)
sub status_code() -> ubyte {
if cbm.READST()==128 {
return 255
}
cbm.SETNAM(0, list_filename)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN() ; open 15,8,15
if_cs
goto io_error
void cbm.CHKIN(15) ; use #15 as input channel
list_filename[0] = cbm.CHRIN()
list_filename[1] = cbm.CHRIN()
list_filename[2] = 0
while cbm.READST()==0 {
void cbm.CHRIN()
}
cbm.CLRCHN() ; restore default i/o devices
cbm.CLOSE(15)
return conv.str2ubyte(list_filename)
io_error:
cbm.CLRCHN()
cbm.CLOSE(15)
return 255
}
; saves a block of memory to disk, including the default 2 byte prg header.
sub save(uword filenameptr, uword startaddress, uword savesize) -> bool {
return internal_save_routine(filenameptr, startaddress, savesize, false)
}
; like save() but omits the 2 byte prg header.
sub save_raw(uword filenameptr, uword startaddress, uword savesize) -> bool {
return internal_save_routine(filenameptr, startaddress, savesize, true)
}
sub internal_save_routine(uword filenameptr, uword startaddress, uword savesize, bool headerless) -> bool {
cbm.SETNAM(strings.length(filenameptr), filenameptr)
cbm.SETLFS(1, drivenumber, 0)
uword @shared end_address = startaddress + savesize
cx16.r0L = 0
%asm {{
lda startaddress
sta P8ZP_SCRATCH_W1
lda startaddress+1
sta P8ZP_SCRATCH_W1+1
ldx end_address
ldy end_address+1
lda headerless
beq +
lda #<P8ZP_SCRATCH_W1
jsr cx16.BSAVE
bra ++
+ lda #<P8ZP_SCRATCH_W1
jsr cbm.SAVE
+ php
plp
}}
if_cc
cx16.r0L = cbm.READST()==0 as ubyte
return cx16.r0L as bool
}
; Use kernal LOAD routine to load the given program file in memory.
; This is similar to Basic's LOAD "filename",drive / LOAD "filename",drive,1
; If you don't give an address_override, the location in memory is taken from the 2-byte file header.
; If you specify a custom address_override, the first 2 bytes in the file are ignored
; and the rest is loaded at the given location in memory.
; Returns the end load address+1 if successful or 0 if a load error occurred.
; NOTE: when the load is larger than 64Kb and/or spans multiple RAM banks
; (which is possible on the Commander X16), the returned size is not correct,
; because it doesn't take the number of ram banks into account.
; You can use the load_size() function to calcuate the size in this case.
; NOTE: data is read into the current Ram bank if you're reading into banked ram.
; if you require loading into another ram bank, you have to set that
; yourself using cx16.rambank(bank) before calling load().
sub load(uword filenameptr, uword address_override) -> uword {
return internal_load_routine(filenameptr, address_override, false)
}
; Identical to load(), but DOES INCLUDE the first 2 bytes in the file.
; No program header is assumed in the file. Everything is loaded.
; See comments on load() for more details.
sub load_raw(uword filenameptr, uword startaddress) -> uword {
return internal_load_routine(filenameptr, startaddress, true)
}
sub internal_load_routine(uword filenameptr, uword address_override, bool headerless) -> uword {
cbm.SETNAM(strings.length(filenameptr), filenameptr)
ubyte secondary = 1
cx16.r1 = 0
if address_override!=0
secondary = 0
if headerless
secondary |= %00000010 ; activate cx16 kernal headerless load support
cbm.SETLFS(1, drivenumber, secondary)
%asm {{
lda #0
ldx address_override
ldy address_override+1
jsr cbm.LOAD
bcs +
stx cx16.r1
sty cx16.r1+1
+
}}
return cx16.r1
}
sub delete(uword filenameptr) {
; -- delete a file on the drive
list_filename[0] = 's'
list_filename[1] = ':'
ubyte flen = strings.copy(filenameptr, &list_filename+2)
cbm.SETNAM(flen+2, list_filename)
cbm.SETLFS(1, drivenumber, 15)
void cbm.OPEN()
cbm.CLRCHN()
cbm.CLOSE(1)
}
sub rename(uword oldfileptr, uword newfileptr) {
; -- rename a file on the drive
list_filename[0] = 'r'
list_filename[1] = ':'
ubyte flen_new = strings.copy(newfileptr, &list_filename+2)
list_filename[flen_new+2] = '='
ubyte flen_old = strings.copy(oldfileptr, &list_filename+3+flen_new)
cbm.SETNAM(3+flen_new+flen_old, list_filename)
cbm.SETLFS(1, drivenumber, 15)
void cbm.OPEN()
cbm.CLRCHN()
cbm.CLOSE(1)
}
sub send_command(uword commandptr) {
; -- send a dos command to the drive (don't read any response)
cbm.SETNAM(strings.length(commandptr), commandptr)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN()
cbm.CLRCHN()
cbm.CLOSE(15)
}
; CommanderX16 extensions over the basic C64/C128 diskio routines:
; For use directly after a load or load_raw call (don't mess with the ram bank yet):
; Calculates the number of bytes loaded (files > 64Kb are truncated to 16 bits)
sub load_size(ubyte startbank, uword startaddress, uword endaddress) -> uword {
return $2000 * (cx16.getrambank() - startbank) + endaddress - startaddress
}
asmsub vload(str name @R0, ubyte bank @A, uword startaddress @R1) clobbers(X, Y) -> bool @A {
; -- like the basic command VLOAD "filename",drivenumber,bank,address
; loads a file into Vera's video memory in the given bank:address, returns success in A
; the file has to have the usual 2 byte header (which will be skipped)
%asm {{
clc
internal_vload:
pha
ldx drivenumber
bcc +
ldy #%00000010 ; headerless load mode
bne ++
+ ldy #0 ; normal load mode
+ lda #1
jsr cbm.SETLFS
lda cx16.r0
ldy cx16.r0+1
jsr prog8_lib.strlen
tya
ldx cx16.r0
ldy cx16.r0+1
jsr cbm.SETNAM
pla
clc
adc #2
ldx cx16.r1
ldy cx16.r1+1
stz P8ZP_SCRATCH_B1
jsr cbm.LOAD
bcs +
inc P8ZP_SCRATCH_B1
+ jsr cbm.CLRCHN
lda #1
jsr cbm.CLOSE
lda P8ZP_SCRATCH_B1
rts
}}
}
asmsub vload_raw(str name @R0, ubyte bank @A, uword startaddress @R1) clobbers(X, Y) -> bool @A {
; -- like the basic command BVLOAD "filename",drivenumber,bank,address
; loads a file into Vera's video memory in the given bank:address, returns success in A
; the file is read fully including the first two bytes.
%asm {{
sec
jmp vload.internal_vload
}}
}
; note: There is no vsave_raw() routine because the Kernal doesn't have a VSAVE routine.
; You'll have to write your own loop that reads vram data and use
; cbm.CHROUT or cx16.MCIOUT to write it to an open output file.
sub chdir(str path) {
; -- change current directory.
list_filename[0] = 'c'
list_filename[1] = 'd'
list_filename[2] = ':'
void strings.copy(path, &list_filename+3)
send_command(list_filename)
}
sub mkdir(str name) {
; -- make a new subdirectory.
list_filename[0] = 'm'
list_filename[1] = 'd'
list_filename[2] = ':'
void strings.copy(name, &list_filename+3)
send_command(list_filename)
}
sub rmdir(str name) {
; -- remove a subdirectory.
void strings.find(name, '*')
if_cs
return ; refuse to act on a wildcard *
list_filename[0] = 'r'
list_filename[1] = 'd'
list_filename[2] = ':'
void strings.copy(name, &list_filename+3)
send_command(list_filename)
}
sub curdir() -> uword {
; return current directory name or 0 if error
; special X16 dos command to only return the current path in the entry list (R42+)
const ubyte MAX_PATH_LEN=80
uword reversebuffer = memory("curdir_buffer", MAX_PATH_LEN, 0)
cx16.r12 = reversebuffer + MAX_PATH_LEN-1
@(cx16.r12)=0
cbm.SETNAM(3, "$=c")
cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
void cbm.OPEN() ; open 12,8,0,"$=c"
if_cs
goto io_error
reset_read_channel()
repeat 6 {
void cbm.CHRIN()
}
while cbm.CHRIN()!=0 {
; skip first line (drive label)
}
while cbm.CHRIN()!='"' {
; skip to first name
}
ubyte status = cbm.READST()
cx16.r10 = &list_filename
while status==0 {
repeat {
@(cx16.r10) = cbm.CHRIN()
if @(cx16.r10)==0
break
cx16.r10++
}
while @(cx16.r10)!='"' and cx16.r10>=&list_filename {
@(cx16.r10)=0
cx16.r10--
}
@(cx16.r10)=0
prepend(list_filename)
cx16.r10 = &list_filename
while cbm.CHRIN()!='"' and status==0 {
status = cbm.READST()
; skipping up to next entry name
}
}
io_error:
cbm.CLRCHN()
cbm.CLOSE(READ_IO_CHANNEL)
if status!=0 and status & $40 == 0
return 0
if @(cx16.r12)==0 {
cx16.r12--
@(cx16.r12)='/'
}
return cx16.r12
sub prepend(str dir) {
if dir[0]=='/' and dir[1]==0
return
cx16.r9L = strings.length(dir)
cx16.r12 -= cx16.r9L
sys.memcopy(dir, cx16.r12, cx16.r9L)
cx16.r12--
@(cx16.r12)='/'
}
}
sub relabel(str name) {
; -- change the disk label.
list_filename[0] = 'r'
list_filename[1] = '-'
list_filename[2] = 'h'
list_filename[3] = ':'
void strings.copy(name, &list_filename+4)
send_command(list_filename)
}
sub exists(str filename) -> bool {
; -- returns true if the given file exists on the disk, otherwise false
if f_open(filename) {
f_close()
return true
}
return false
}
sub f_seek(uword pos_hiword, uword pos_loword) {
; -- seek in the reading file opened with f_open, to the given 32-bits position
; Note: this will not work if you have already read the last byte of the file! Then you must close and reopen the file first.
ubyte[6] command = ['p',0,0,0,0,0]
command[1] = READ_IO_CHANNEL ; f_open uses this secondary address
command[2] = lsb(pos_loword)
command[3] = msb(pos_loword)
command[4] = lsb(pos_hiword)
command[5] = msb(pos_hiword)
cbm.SETNAM(sizeof(command), &command)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN()
cbm.CLOSE(15)
reset_read_channel() ; back to the read io channel
}
sub f_seek_w(uword pos_hiword, uword pos_loword) {
; -- seek in the output file opened with f_open_w_seek, to the given 32-bits position
diskio.f_seek.command[1] = WRITE_IO_CHANNEL ; f_open_w uses this secondary address
diskio.f_seek.command[2] = lsb(pos_loword)
diskio.f_seek.command[3] = msb(pos_loword)
diskio.f_seek.command[4] = lsb(pos_hiword)
diskio.f_seek.command[5] = msb(pos_hiword)
cbm.SETNAM(sizeof(diskio.f_seek.command), &diskio.f_seek.command)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN()
cbm.CLOSE(15)
reset_write_channel() ; back to the write io channel
}
asmsub f_tell() -> uword @R0, uword @R1, uword @R2, uword @R3 {
; -- Returns the current read position of the opened read file,
; in R0 and R1 (low + high words) and the file size in R2 and R3 (low + high words).
; Returns 0 as size if the command is not supported by the DOS implementation/version.
%asm {{
jmp internal_f_tell
}}
}
sub internal_f_tell() {
; gets the (32 bits) position + file size of the opened read file channel
ubyte[2] command = ['t',0]
command[1] = READ_IO_CHANNEL ; f_open uses this secondary address
cbm.SETNAM(sizeof(command), &command)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN()
void cbm.CHKIN(15) ; use #15 as input channel
bool success=false
; valid response starts with "07," followed by hex notations of the position and filesize
if cbm.CHRIN()=='0' and cbm.CHRIN()=='7' and cbm.CHRIN()==',' {
cx16.r1 = read4hex()
cx16.r0 = read4hex() ; position in R1:R0
void cbm.CHRIN() ; separator space
cx16.r3 = read4hex()
cx16.r2 = read4hex() ; filesize in R3:R2
success = true
}
while cbm.READST()==0 {
cx16.r5L = cbm.CHRIN()
if cx16.r5L=='\r' or cx16.r5L=='\n'
break
}
cbm.CLOSE(15)
reset_read_channel() ; back to the read io channel
if success
return
cx16.r0 = cx16.r1 = cx16.r2 = cx16.r3 = 0
}
sub read4hex() -> uword {
str hex = "0000"
hex[0] = cbm.CHRIN()
hex[1] = cbm.CHRIN()
hex[2] = cbm.CHRIN()
hex[3] = cbm.CHRIN()
return conv.hex2uword(hex)
}
}