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mirror of https://github.com/hsoft/collapseos.git synced 2024-12-24 14:38:05 +11:00

fs: add "fdel" command

This commit is contained in:
Virgil Dupras 2019-04-23 13:29:16 -04:00
parent 5eca14d49a
commit 684f083e8e
3 changed files with 92 additions and 50 deletions

View File

@ -7,6 +7,10 @@
ASCII_CR .equ 0x0d
ASCII_LF .equ 0x0a
; *** DATA ***
; Useful data to point to, when a pointer is needed.
P_NULL: .db 0
; *** REGISTER FIDDLING ***
; add the value of A into DE
@ -32,6 +36,14 @@ intoDE:
pop af
ret
intoHL:
push de
ex de, hl
call intoDE
ex de, hl
pop de
ret
; add the value of A into HL
addHL:
add a, l
@ -70,6 +82,18 @@ unsetZ:
; *** STRINGS ***
; Fill B bytes at (HL) with A
fill:
push bc
push hl
.loop:
ld (hl), a
inc hl
djnz .loop
pop hl
pop bc
ret
; Increase HL until the memory address it points to is equal to A for a maximum
; of 0xff bytes. Returns the new HL value as well as the number of bytes
; iterated in A.

View File

@ -74,6 +74,10 @@
; *** CONSTS ***
FS_MAX_NAME_SIZE .equ 0x1a
FS_BLOCKSIZE .equ 0x100
FS_META_ALLOC_OFFSET .equ 3
FS_META_FSIZE_OFFSET .equ 4
FS_META_FNAME_OFFSET .equ 6
; Size in bytes of a FS handle:
; * 2 bytes for starting offset
; * 2 bytes for file size (we could fetch it from metadata all the time, but it
@ -83,6 +87,7 @@ FS_BLOCKSIZE .equ 0x100
; to change the size of the file.
FS_HANDLE_SIZE .equ 6
FS_ERR_NO_FS .equ 0x5
FS_ERR_NOT_FOUND .equ 0x6
; *** VARIABLES ***
; A copy of BLOCKDEV_SEL when the FS was mounted. 0 if no FS is mounted.
@ -105,6 +110,13 @@ P_FS_MAGIC:
; *** CODE ***
fsInit:
xor a
ld hl, FS_BLKSEL
ld b, FS_RAMEND-FS_BLKSEL
call fill
ret
; *** Navigation ***
; Resets FS_PTR to the beginning. Errors out if no FS is mounted.
@ -125,7 +137,7 @@ fsNext:
push bc
push de
push hl
ld a, (FS_META+3)
ld a, (FS_META+FS_META_ALLOC_OFFSET)
cp 0
jr z, .error ; if our block allocates 0 blocks, this is the
; end of the line.
@ -198,10 +210,7 @@ fsInitMeta:
ldir
xor a
ld b, 0x20-3
.loop:
ld (hl), a
inc hl
djnz .loop
call fill
pop hl
pop de
pop af
@ -244,7 +253,7 @@ fsAlloc:
; 1 - the block is unallocated (0 alloc size)
; 2 - the block is allocated, but there are no next block
; So, what we need to do is check our allocation size
call fsAllocatedBlocks
ld a, (FS_META+FS_META_ALLOC_OFFSET)
cp 0
jr z, .proceed ; 0 allocated blocks? this is our block
; > 0 allocated blocks. We need to allocate further
@ -260,9 +269,9 @@ fsAlloc:
call fsInitMeta
pop af ; now we want our A arg
ld a, 1
ld (FS_META+3), a
ld (FS_META+FS_META_ALLOC_OFFSET), a
pop hl ; now we want our HL arg
ld de, FS_META+6
ld de, FS_META+FS_META_FNAME_OFFSET
ld bc, FS_MAX_NAME_SIZE
ldir
; Good, FS_META ready. Now, let's update FS_PTR because it hasn't been
@ -292,43 +301,12 @@ fsIsValid:
pop hl
ret
; Return, in A, the number of allocated blocks at current position.
fsAllocatedBlocks:
ld a, (FS_META+3)
; Returns wheter current block is deleted in Z flag.
fsIsDeleted:
ld a, (FS_META+FS_META_FNAME_OFFSET)
cp 0 ; Z flag is our answer
ret
; Return, in HL, the file size at current position.
fsFileSize:
ld hl, (FS_META+4)
ret
; Return HL, which points to a null-terminated string which contains the
; filename at current position.
fsFileName:
ld hl, FS_META+6
ret
; Change name of current file to name in (HL)
fsRename:
push af
push hl ; save filename for later
call fsPlace
ld a, BLOCKDEV_SEEK_FORWARD
ld hl, 6
call blkSeek
pop hl ; now we need the filename
push hl ; ... but let's preserve it for the caller
.loop:
ld a, (hl)
cp 0
jr z, .end
call blkPutC
inc hl
jr .loop
.end:
pop hl
pop af
ret
; *** Handling ***
; Open file at current position into handle at (HL)
@ -385,9 +363,12 @@ flsCmd:
call fsBegin
jr nz, .error
.loop:
call fsFileName
call fsIsDeleted
jr z, .skip
ld hl, FS_META+FS_META_FNAME_OFFSET
call printstr
call printcrlf
.skip:
call fsNext
jr z, .loop ; Z set? fsNext was successfull
xor a
@ -402,14 +383,42 @@ flsCmd:
fnewCmd:
.db "fnew", 0b001, 0b1001, 0b001
push hl
push de
ld a, (hl)
ex de, hl
inc de
call intoDE
ex de, hl
inc hl
call intoHL
call fsAlloc
pop de
pop hl
xor a
ret
; Deletes filename with specified name
fdelCmd:
.db "fdel", 0b1001, 0b001, 0
push hl
push de
ex hl, de
call intoDE ; DE now holds the string we look for
call fsBegin
jr nz, .notfound
ld a, FS_MAX_NAME_SIZE
.loop:
ld hl, FS_META+FS_META_FNAME_OFFSET
call strncmp
jr z, .found
call fsNext
jr z, .loop
; End of chain, not found
jr .notfound
.found:
xor a
; Set filename to zero to flag it as deleted
ld (FS_META+FS_META_FNAME_OFFSET), a
call fsWriteMeta
; a already to 0, our result.
jr .end
.notfound:
ld a, FS_ERR_NOT_FOUND
.end:
pop de
pop hl
ret

View File

@ -66,3 +66,12 @@ printHex:
pop af
ret
; Print the hex pair in HL
printHexPair:
push af
ld a, h
call printHex
ld a, l
call printHex
pop af
ret