recipes/trs80: add CFS support

This allows us to write contents from RS-232 directly to floppy! it works!

recipes/trs80/README.md

@@ -204,4 +204,21 @@ get a usable Collapse OS prompt!
 Like with the `recv` program, nothing stops you from dumping that binary to a
 floppy.
 
-Have fun!
+## Configuration
+
+In addition to the generic basic shell, this build of Collapse OS has support
+for floppy drive `:1` as a block device (mapped to device `0`). Block device
+commands work as expected.
+
+In addition to this, there is a `flush` command to ensure that dirty buffers are
+synced to disk. Make sure you run this after a write operation or before
+swapping disks.
+
+On top of that, there's CFS support builtin. To enable a FS, type `fson` while
+the active block device is properly placed (you can initialize a new FS by
+writing `CFS\0\0\0\0` to the disk). If it doesn't error out, commands like
+`fls` and `fnew` will work. Don't forget to flush when you're finished :)
+
+There is also a custom `recv` command that does the same "ping pong" as in
+`recv.asm`, but once. It puts the result in `A`. This can be useful to send down
+a raw CFS: you just need a while loop that repeatedly call `recv:putb a`.

recipes/trs80/glue.asm

@@ -1,5 +1,9 @@
 ; RAMSTART is a label at the end of the file
 .equ	RAMEND		0xcfff
+; Address of the *CL driver. Same as in recv.asm
+.equ	COM_DRV_ADDR	0x0238
+; in sync with user.h. Last BAS_RAMEND: 0x5705
+.equ	USER_CODE	0x5800
 
 ; Free memory in TRSDOS starts at 0x3000
 .org	0x3000
@@ -7,6 +11,7 @@
 
 .inc "err.h"
 .inc "blkdev.h"
+.inc "fs.h"
 .inc "ascii.h"
 .inc "core.asm"
 .inc "str.asm"
@@ -17,16 +22,22 @@
 .inc "trs80/floppy.asm"
 
 .equ	BLOCKDEV_RAMSTART	FLOPPY_RAMEND
-.equ	BLOCKDEV_COUNT		1
+.equ	BLOCKDEV_COUNT		3
 .inc "blockdev.asm"
 ; List of devices
 .dw	floppyGetB, floppyPutB
+.dw	blk1GetB, blk1PutB
+.dw	blk2GetB, blk2PutB
 
 .equ	STDIO_RAMSTART	BLOCKDEV_RAMEND
 .equ	STDIO_GETC	trs80GetC
 .equ	STDIO_PUTC	trs80PutC
 .inc "stdio.asm"
 
+.equ	FS_RAMSTART	STDIO_RAMEND
+.equ	FS_HANDLE_COUNT	2
+.inc "fs.asm"
+
 ; The TRS-80 generates a double line feed if we give it both CR and LF.
 .equ	printcrlf	printcr
 
@@ -34,7 +45,7 @@
 
 ; RAM space used in different routines for short term processing.
 .equ	SCRATCHPAD_SIZE	STDIO_BUFSIZE
-.equ	SCRATCHPAD	STDIO_RAMEND
+.equ	SCRATCHPAD	FS_RAMEND
 .inc "lib/util.asm"
 .inc "lib/ari.asm"
 .inc "lib/parse.asm"
@@ -48,14 +59,19 @@
 .inc "basic/var.asm"
 .equ	BUF_RAMSTART	VAR_RAMEND
 .inc "basic/buf.asm"
+.equ	BFS_RAMSTART	BUF_RAMEND
+.inc "basic/fs.asm"
 .inc "basic/blk.asm"
 .inc "basic/floppy.asm"
-.equ	BAS_RAMSTART	BUF_RAMEND
+.equ	BAS_RAMSTART	BFS_RAMEND
 .inc "basic/main.asm"
 
+.out	BAS_RAMEND
+
 init:
 	ld	sp, RAMEND
 	call	floppyInit
+	call	fsInit
 	call	basInit
 	ld	hl, basFindCmdExtra
 	ld	(BAS_FINDHOOK), hl
@@ -73,11 +89,84 @@ printcr:
 	pop	af
 	ret
 
+; Receive a byte from *cl and put it in A.
+; Returns A > 0xff when receiving the last byte
+recvCmd:
+	xor	a
+	ld	(VAR_TBL+1), a	; pre-set MSB
+	; put a 0xff mask in B, which will become 0x7f if we receive a 0x20
+	ld	b, 0xff
+.inner:
+	ld	a, 0x03		; @GET
+	ld	de, COM_DRV_ADDR
+	rst	0x28
+	jr	nz, .maybeerror
+	or	a
+	jr	z, .eof		; Sending a straight NULL ends the comm.
+	; @PUT that char back
+	ld	c, a
+	ld	a, 0x04		; @PUT
+	ld	de, COM_DRV_ADDR
+	rst	0x28
+	ret	nz		; error
+	ld	a, c
+	cp	0x20
+	jr	z, .escapechar
+	; not an escape char, good
+	and	b		; apply mask
+	ld	(VAR_TBL), a
+	xor	a		; ensure Z
+	ret
+.maybeerror:
+	; was it an error?
+	or	a
+	jr	z, .inner	; not an error, just loop
+	ret			; error
+.escapechar:
+	ld	b, 0x7f
+	jr	.inner
+.eof:
+	dec	a		; A = 0xff
+	ld	(VAR_TBL+1), a
+	xor	a		; ensure Z
+	ret
+
 basFindCmdExtra:
 	ld	hl, basFloppyCmds
 	call	basFindCmd
 	ret	z
 	ld	hl, basBLKCmds
+	call	basFindCmd
+	ret	z
+	ld	hl, basFSCmds
+	call	basFindCmd
+	ret	z
+	ld	hl, .cmds
 	jp	basFindCmd
 
+.cmds:
+	.db	"recv", 0
+	.dw	recvCmd
+	.db	0xff		; end of table
+
+; *** blkdev 1: file handle 0 ***
+
+blk1GetB:
+	ld	ix, FS_HANDLES
+	jp	fsGetB
+
+blk1PutB:
+	ld	ix, FS_HANDLES
+	jp	fsPutB
+
+; *** blkdev 2: file handle 1 ***
+
+blk2GetB:
+	ld	ix, FS_HANDLES+FS_HANDLE_SIZE
+	jp	fsGetB
+
+blk2PutB:
+	ld	ix, FS_HANDLES+FS_HANDLE_SIZE
+	jp	fsPutB
+
 RAMSTART:

recipes/trs80/recv.asm

@@ -1,7 +1,17 @@
-	ld	hl, 0x3000	; memory address where to put contents.
+.equ	COM_DRV_ADDR	0x0238	; replace with *CL's DCB addr
+.equ	DEST_ADDR	0x3000	; memory address where to put contents.
+
+; We process the 0x20 exception by pre-putting a mask in the (HL) we're going
+; to write to. If it wasn't a 0x20, we put a 0xff mask. If it was a 0x20, we
+; put a 0x7f mask.
+
+	ld	hl, DEST_ADDR
 loop:
+	ld	a, 0xff
+	ld	(hl), a		; default mask
+loop2:
 	ld	a, 0x03		; @GET
-	ld	de, 0xffff	; replace with *CL's DCB addr
+	ld	de, COM_DRV_ADDR
 	rst	0x28
 	jr	nz, maybeerror
 	or	a
@@ -9,25 +19,24 @@ loop:
 	; @PUT that char back
 	ld	c, a
 	ld	a, 0x04		; @PUT
-	ld	de, 0xffff	; replace with *CL's DCB addr
 	rst	0x28
 	jr	nz, error
 	ld	a, c
 	cp	0x20
-	jr	z, adjust
-write:
+	jr	z, escapechar
+	; not an escape char, just apply the mask and write
+	and	(hl)
 	ld	(hl), a
 	inc	hl
 	jr	loop
-adjust:
-	dec	hl
-	ld	a, (hl)
-	and	0x7f
-	jr	write
+escapechar:
+	; adjust by setting (hl) to 0x7f
+	res	7, (hl)
+	jr	loop2
 maybeerror:
 	; was it an error?
 	or	a
-	jr	z, loop		; not an error, just loop
+	jr	z, loop2	; not an error, just loop
 	; error
 error:
 	ld	c, a		; Error code from @GET/@PUT

tools/ttysafe.c

@@ -4,8 +4,8 @@
 /* Converts stdin to a content that is "tty safe", that is, that it doesn't
  * contain ASCII control characters that can mess up serial communication.
  * How it works is that it leaves any char > 0x20 intact, but any char <= 0x20
- * is replaced by two chars: char|0x80, 0x20. A 0x20 char always indicate "take
- * the char you've just received and unset the 7th bit from it".
+ * is replaced by two chars: 0x20, then char|0x80. A 0x20 char always indicate
+ * "take the next char you'll receive and unset the 7th bit from it".
  */
 
 int main(void)
@@ -13,8 +13,8 @@ int main(void)
     int c = getchar();
     while (c != EOF) {
         if (c <= 0x20) {
-            putchar(c|0x80);
             putchar(0x20);
+            putchar(c|0x80);
         } else {
             putchar(c&0xff);
         }