mirror of
https://github.com/RevCurtisP/C02.git
synced 2024-11-22 01:31:33 +00:00
206 lines
7.1 KiB
Plaintext
206 lines
7.1 KiB
Plaintext
; C02 filesys.h02 assembly language subroutines
|
|
; for all Commodore 8 bit machines
|
|
; Requires external functions ADDDST, FOPENA, FREAD, FSKIP,
|
|
; FSBCMD, FSCBFR, FSCDRA, FSGBFR, FSOPTS, and SETSRC
|
|
; external zero page locations BFRHI, BFRLO, DSTHI, DSTLO,
|
|
; SRCHI, and SRCLO
|
|
; and external locations FSCNTR, FSDVNO, FSLFNO, and TEMP0
|
|
|
|
;String Constants
|
|
FSDIRP DC "$0:",0 ;Disk Directory Prefix
|
|
|
|
;opndir() - Open Directory for Reading
|
|
;Args: A = Drive/Options
|
|
; Y,X = Pointer to Directory Name
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: SRCHI,SRCLO = Pointer to Directory Name
|
|
;Returns: A = File Pointer
|
|
; 0 - Error
|
|
OPNDIR: JSR SETSRC ;Save Directory Pointer
|
|
STY FSCNTR ;Set File Count to 0
|
|
JSR FSOPTS ;Parse Options Byte
|
|
JSR FSCDRV ;If Device is Not Disk Drive
|
|
BEQ CLSDIX ; Return Error
|
|
LDA #36 ;Set Command to "$"
|
|
JSR FSBCMD ;and Build Command String
|
|
SEC ;Set Flag to Concatenate
|
|
JSR FSCBFR ;Concatenate Directory Name to Buffer
|
|
JSR FSGBFR ;Get String Buffer Address
|
|
JMP FOPENA ;Execute File Open (Alternate Entry Point)
|
|
|
|
;clsdir() - Close Directory File
|
|
;Args: A = Directory File Pointer
|
|
;Returns: A = Error Code
|
|
; 0 - Success
|
|
CLSDIR: ORA #0 ;Check File Pointer
|
|
BEQ CLSDIX ;If Not Zero
|
|
JMP FCLOSE ;Close File Channel
|
|
CLSDIX: RTS
|
|
|
|
;rdhdr() - Read Directory Header
|
|
;Note: Call once before first rddir()
|
|
;Args: A = Directory File Pointer
|
|
; Y,X = Pointer to HDRENT buffer
|
|
;Sets: DSTHI,DSTLO = Pointer to HDRENT buffer
|
|
;Returns: A = Disk Type
|
|
; Y = Error Code (0=None)
|
|
RDHDR: JSR SETDST ;Set Destination Address
|
|
LDY #2 ;Set Record Length
|
|
JSR FREAD ;and Read Record
|
|
BCS RDHDRZ ;If Error, Exit
|
|
STY TEMP0 ;Set Skipped Bytes to 0
|
|
LDA (DSTLO),Y ;Get Disk Version
|
|
PHA ;and Save It
|
|
CMP #$43 ;If 8050/8250
|
|
LDY #2 ;Skip Unused bytes
|
|
BNE RDHDRC
|
|
CMP #$41 ;If 4040/1541/1571
|
|
BNE RDHDRD ; Skip BAM
|
|
LDA FSLFNO ; Get Channel
|
|
LDY #140 ; Set Record Length
|
|
RDHDRC: STY TEMP0 ; Save Number of Skipped Bytes
|
|
JSR FSKIP ; and Skip Bytes
|
|
BCS RDHDRX ; If Error, Exit
|
|
RDHDRD: LDA #2 ;Add 2 Bytes
|
|
JSR ADDDST ;to Destination Address
|
|
LDA FSLFNO ;Get Channel
|
|
LDY #24 ;Set Record Length
|
|
JSR FREAD ;and Read Record
|
|
BCS RDHDRX ;If Error, Exit
|
|
LDA #228 ;Set Padding Bytes
|
|
SEC
|
|
SBC TEMP0 ;Subtract Bytes Skipped
|
|
TAY ;Set as Record Length
|
|
LDA FSLFNO ;Get Channel
|
|
JSR FSKIP ;and Skip Bytes
|
|
LDY #23 ;Set Index to 24
|
|
RDHDRN: LDA (DSTLO),Y ;Load Byte
|
|
CMP #$A0 ;If Shifted Space
|
|
BNE RDHDRS
|
|
LDA #0 ;Change to 0
|
|
STA (DSTLO),Y
|
|
RDHDRS: DEY ;Decrement Index
|
|
BPL RDHDRN ;and Loop if Not Negative
|
|
INY ;Set Error Code to 0
|
|
RDHDRX: PLA ;Retrieve Disk Type
|
|
RDHDRZ: RTS
|
|
|
|
;rddir() - Read Directory Entry
|
|
;Args: A = Directory File Pointer
|
|
; Y,X = Pointer to DIRENT buffer
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: DSTHI,DSTLO = Pointer to DIRENT buffer
|
|
;Returns: A = File Type (0=Null Entry)
|
|
; Y = Error Code (0=None)
|
|
RDDIR: JSR SETDST ;Set Destination Address
|
|
TAX ;Save LFN
|
|
LDY #32 ;Set Record Length
|
|
INC FSCNTR ;Increment File Count
|
|
LDA FSCNTR ;Load It
|
|
AND #$07 ;Modulo 8
|
|
BNE RDDIRB ;If 0
|
|
LDY #30 ; Change Record Length
|
|
RDDIRB: TXA ;Restore LFN
|
|
JSR FREAD ;and Read Record
|
|
RDDIRC: LDA #0 ;Initialize Return Value
|
|
BCS RDDIRX ;If Error, Exit
|
|
LDA (DSTLO),Y ;Get File Type
|
|
PHA ;and Save it
|
|
LDA #3 ;Add 3 Bytes
|
|
JSR ADDDST ;to Destination Address
|
|
LDY #15 ;Set Index to 15
|
|
RDDIRN: LDA (DSTLO),Y ;Load Byte
|
|
CMP #$A0 ;If Shifted Space
|
|
BNE RDDIRS
|
|
LDA #0 ;Change to 0
|
|
STA (DSTLO),Y
|
|
RDDIRS: DEY ;Decrement Index
|
|
BPL RDDIRN ;and Loop if Not Negative
|
|
INY ;Set Error Code to 0
|
|
PLA ;Restore File Type
|
|
RDDIRX: RTS
|
|
|
|
;setdrv() - Set Current Drive
|
|
;Args: A = Drive Identifier
|
|
;Returns: A = Drive Identifier
|
|
; 0 - None/Error
|
|
SETDRV: JSR FSCDRA ;Check Device Number
|
|
BCS SETDRX ;If Disk Drive
|
|
STA FSDVNO ; Write to Device#
|
|
SETDRX: RTS
|
|
|
|
;getdrv() - Get Current Drive
|
|
;Returns: A = Drive Identifier
|
|
; 0 - None/Error
|
|
GETDRV: LDA FSDVNO ;Load Current Device#
|
|
JMP FSCDRA ;Check if Disk Drive
|
|
|
|
;setdir() - Set Current Directory
|
|
;Args: A = Drive Identifier
|
|
; Y,X = Pointer to Directory Name
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: SRCHI,SRCLO = Pointer to Directory Name
|
|
;Returns: A = Error Code
|
|
; $00 - Successful
|
|
; $FF - Inapplicable
|
|
SETDIR: JSR SETSRC ;Save Pointer
|
|
JSR FSOPTS ;Parse Drive Argument
|
|
JSR FSGBFR ;Get String Buffer Address
|
|
;command is "/0:Directory"
|
|
;assuming 0 is disk number
|
|
;of course this is switched from normal command syntax
|
|
RTS
|
|
|
|
;getdir() - Get Current Directory
|
|
;Args: A = Drive Identifier
|
|
; Y,X = Pointer to String
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: DSTHI,DSTLO = Pointer to String
|
|
;Returns: A - Length of Directory Name
|
|
; $00 - Root
|
|
; $FF - Inapplicable
|
|
GETDIR: ;Return Inapplicable (fall through)
|
|
|
|
;mkdir() - Create Directory
|
|
;Args: A = Drive Identifier
|
|
; Y,X = Pointer to Directory Name
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: SRCHI,SRCLO = Pointer to Directory Name
|
|
;Returns: A = Error Code
|
|
; $00 - Successful
|
|
; $FF - Inapplicable
|
|
MKDIR: ;Return Inapplicable (fall through)
|
|
|
|
;rmdir() - Remove Directory
|
|
;Args: A = Drive Identifier
|
|
; Y,X = Pointer to Directory Name
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: SRCHI,SRCLO = Pointer to Directory Name
|
|
;Returns: A = Error Code
|
|
; $00 - Successful
|
|
; $FF - Inapplicable
|
|
RMDIR: ;Return Inapplicable (fall through)
|
|
|
|
;remove() - Delete File
|
|
;Args: A = Drive Identifier
|
|
; Y,X = Pointer to File Name
|
|
;Uses: BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: SRCHI,SRCLO = Pointer to File Name
|
|
;Returns: A = Error Code
|
|
; $00 - Successful
|
|
; $FF - Inapplicable
|
|
REMOVE: ;Return Inapplicable (fall through)
|
|
|
|
;rename() - Rename File
|
|
;Args: A = Drive Identifier
|
|
; Y,X = Pointer to Destination File Name
|
|
;Uses: SRCHI,SRCLO = Pointer to Source File Name
|
|
; BFRHI,BFRLO = Pointer to Work Buffer
|
|
;Sets: DSTHI,DSTLO = Pointer to Destination File Name
|
|
;Returns: A = Error Code
|
|
; $00 - Successful
|
|
; $FF - Inapplicable
|
|
RENAME: LDA #$FF ;Return Inapplicable
|
|
RTS
|
|
|