Finally: Commodore file I/O

git-svn-id: svn://svn.cc65.org/cc65/trunk@1531 b7a2c559-68d2-44c3-8de9-860c34a00d81
2002-11-16 23:45:15 +00:00
parent 9e74c2b26f
commit 751aaee63d
23 changed files with 1023 additions and 273 deletions
--- a/libsrc/cbm/filename.s
+++ b/libsrc/cbm/filename.s
@@ -0,0 +1,158 @@
+;
+; Ullrich von Bassewitz, 16.11.2002
+;
+; File name handling for CBM file I/O
+;
+
+        .export         fnparse, fnset, fncomplete
+        .export         fnunit, fnlen, fncmd, fnbuf
+
+        .import         __curunit, __filetype
+        .importzp       ptr1
+
+        .include        "ctype.inc"
+        .include        "cbm.inc"
+
+
+;--------------------------------------------------------------------------
+; fnparse: Parse a filename passed in in a/x. Will set the following
+; variables:
+;
+;       fnlen   -> length of filename
+;       fnbuf   -> filename including drive spec
+;       fnunit  -> unit from spec or default unit
+
+
+.proc   fnparse
+
+        sta     ptr1
+        stx     ptr1+1          ; Save pointer to name
+
+; For now we're always using the default unit
+
+        lda     __curunit
+        sta     fnunit
+
+; Check the name for a drive spec
+
+        ldy     #0
+        lda     (ptr1),y
+        sta     fnbuf+0
+        cmp     #'0'
+        beq     digit
+        cmp     #'1'
+        bne     nodrive
+
+digit:  iny
+        lda     (ptr1),y
+        cmp     #':'
+        bne     nodrive
+
+; We found a drive spec, copy it to the buffer
+
+        sta     fnbuf+1
+        iny                     ; Skip colon
+        bne     drivedone       ; Branch always
+
+; We did not find a drive spec, always use drive zero
+
+nodrive:
+        lda     #'0'
+        sta     fnbuf+0
+        lda     #':'
+        sta     fnbuf+1
+        ldy     #$00            ; Reposition to start of name
+
+; Drive spec done. Copy the name into the file name buffer. Check that all
+; file name characters are valid and that the maximum length is not exceeded.
+
+drivedone:
+        lda     #2              ; Length of drive spec
+        sta     fnlen
+
+nameloop:
+        lda     (ptr1),y        ; Get next char from filename
+        beq     namedone        ; Jump if end of name reached
+
+; Check for valid chars in the file name
+
+        tax
+        lda     __ctype,x
+        and     #CT_ALNUM       ; Letters and digits are allowed
+        beq     invalidname
+
+; Check the maximum length, store the character
+
+        ldx     fnlen
+        cpx     #14             ; Maximum length reached?
+        bcs     invalidname
+        lda     (ptr1),y        ; Reload char
+        sta     fnbuf,x         ; Store into buffer
+        inc     fnlen           ; Count characters
+        iny                     ; Next char from name
+        bne     nameloop        ; Branch always
+
+; Invalid file name
+
+invalidname:
+        lda     #33             ; Invalid file name
+
+; Done, we've successfully parsed the name.
+
+namedone:
+        rts
+
+.endproc
+
+
+;--------------------------------------------------------------------------
+; fnset: Tell the kernal about the file name
+
+.proc   fnset
+
+        lda     fnlen
+        ldx     #<fnbuf
+        ldy     #>fnbuf
+        jmp     SETNAM
+
+.endproc
+
+;--------------------------------------------------------------------------
+; fncomplete: Complete a filename by adding ",t,m" where t is the file type
+; and m is the access mode passed in in the A register
+
+.proc	fncomplete
+
+	pha			; Save mode
+	ldx	fnlen
+	lda	#','
+	sta	fnbuf,x
+	inx
+	lda	__filetype
+	sta	fnbuf,x
+	inx
+	lda	#','
+	sta	fnbuf,x
+	inx
+	pla
+	sta	fnbuf,x
+	inx
+	stx	fnlen
+	rts
+
+.endproc
+
+;--------------------------------------------------------------------------
+; Data
+
+.bss
+
+fnunit: .res    1
+fnlen:  .res    1
+
+.data
+fncmd:  .byte   's'             ; Use as scratch command
+fnbuf:  .res    20
+
+
+