prog8/compiler/res/prog8lib/shared_cbm_diskio.p8
Irmen de Jong 25b1043572 c64 diskio: Always call CLRCHN before CHKIN/CHKOUT calls
this seems to work around a Vice emulator issue when using host filesystem disk emulation.
Fixes #156
2024-12-03 19:15:44 +01:00

642 lines
20 KiB
Lua

; shared CBM (C64/C128) disk drive I/O routines.
%import textio
%import conv
%import strings
%import syslib
diskio {
%option merge, 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() {
cbm.CLRCHN()
void cbm.CHKIN(READ_IO_CHANNEL)
}
sub reset_write_channel() {
cbm.CLRCHN()
cbm.CHKOUT(WRITE_IO_CHANNEL)
}
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 & $40 == 0 { ; bit 6=end of file
txt.print("\ni/o error, status: ")
txt.print_ub(status)
txt.nl()
return false
}
return true
}
sub diskname() -> uword {
; -- Returns pointer to disk name string or 0 if failure.
cbm.SETNAM(1, "$")
cbm.SETLFS(READ_IO_CHANNEL, drivenumber, 0)
bool okay = false
void cbm.OPEN() ; open 12,8,0,"$"
if_cs
goto io_error
reset_read_channel()
while cbm.CHRIN()!='"' {
; skip up to entry name
}
if cbm.READST()!=0
goto io_error
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++
}
okay = true
io_error:
cbm.CLRCHN() ; restore default i/o devices
cbm.CLOSE(READ_IO_CHANNEL)
if okay
return &list_filename
return 0
}
; 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
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 input io channel) -----
sub f_open(uword 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
}
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)
if not iteration_in_progress or num_bytes==0
return 0
reset_read_channel()
if num_bytes==1 {
; slightly optimized path 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
%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
}
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.
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!
; I/O error status should be checked by the caller itself via READST() routine.
; 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(uword filenameptr) -> 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!
; NOTE: the default output isn't yet set to this file, you must use reset_write_channel() to do this,
; if you're going to write to it yourself instead of using f_write()!
f_close_w()
cbm.SETNAM(strings.length(filenameptr), filenameptr)
cbm.SETLFS(WRITE_IO_CHANNEL, drivenumber, 1)
void cbm.OPEN() ; open 13,8,1,"filename"
if_cc {
if cbm.READST()==0 {
write_iteration_in_progress = true
cbm.CLRCHN() ; reset default i/o channels
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()
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
; TODO this doesn't seem to work reliably, sometimes READST returns 128 when the drive is just fine
; 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 (CBM-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
}
sub save(uword filenameptr, uword start_address, uword savesize) -> bool {
cbm.SETNAM(strings.length(filenameptr), filenameptr)
cbm.SETLFS(1, drivenumber, 0)
uword @shared end_address = start_address + savesize
cx16.r0L = 0
%asm {{
lda start_address
sta P8ZP_SCRATCH_W1
lda start_address+1
sta P8ZP_SCRATCH_W1+1
lda #<P8ZP_SCRATCH_W1
ldx end_address
ldy end_address+1
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.
sub load(uword filenameptr, uword address_override) -> uword {
cbm.SETNAM(strings.length(filenameptr), filenameptr)
ubyte secondary = 1
cx16.r1 = 0
if address_override!=0
secondary = 0
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
}
; 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 start_address) -> uword {
; read the 2 header bytes separately to skip them
if not f_open(filenameptr)
return 0
cx16.r1 = f_read(start_address, 2)
f_close()
if cx16.r1!=2
return 0
start_address += 2
return load(filenameptr, start_address)
}
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 exists(str filename) -> bool {
; -- returns true if the given file exists on the disk, otherwise false
; DON'T use this if you already have a file open with f_open!
if f_open(filename) {
f_close()
return true
}
return false
}
sub send_command(uword commandptr) {
; -- send a dos command to the drive
cbm.SETNAM(strings.length(commandptr), commandptr)
cbm.SETLFS(15, drivenumber, 15)
void cbm.OPEN()
cbm.CLRCHN()
cbm.CLOSE(15)
}
}