;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; FAT32.INC ;;
;; ;;
;; FAT16/32 functions for MenuetOS ;;
;; ;;
;; Copyright 2002 Paolo Minazzi, paolo.minazzi@inwind.it ;;
;; ;;
;; See file COPYING for details ;;
;; ;;
;; 15.01.2005 get file size/attr/date, file_append - ATV ;;
;; 04.12.2004 skip volume label, file delete bug fixed - ATV ;;
;; 29.11.2004 get_free_FAT changed, append dir bug fixed - ATV ;;
;; 23.11.2004 don't allow overwrite dir with file - ATV ;;
;; 18.11.2004 get_disk_info and more error codes - ATV ;;
;; 17.11.2004 set_FAT/get_FAT and disk cache rewritten - ATV ;;
;; 10.11.2004 removedir clear whole directory structure - ATV ;;
;; 08.11.2004 rename - ATV ;;
;; 30.10.2004 file_read return also dirsize in bytes - ATV ;;
;; 20.10.2004 Makedir/Removedir - ATV ;;
;; 14.10.2004 Partition chain/Fat16 - ATV (thanks drh3xx) ;;
;; 06.9.2004 Fix free space by Mario79 added - MH ;;
;; 24.5.2004 Write back buffer for File_write -VT ;;
;; 20.5.2004 File_read function to work with syscall 58 - VT ;;
;; 30.3.2004 Error parameters at function return - VT ;;
;; 01.5.2002 Bugfix in device write - VT ;;
;; 20.5.2002 Hd status check - VT ;;
;; 29.6.2002 Improved fat32 verification - VT ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
cache_max equ 1919 ; max. is 1919*512+0x610000=0x6ffe00
ERROR_SUCCESS = 0
ERROR_DISK_BASE = 1
ERROR_UNSUPPORTED_FS = 2
ERROR_UNKNOWN_FS = 3
ERROR_PARTITION = 4
ERROR_FILE_NOT_FOUND = 5
ERROR_END_OF_FILE = 6
ERROR_MEMORY_POINTER = 7
ERROR_DISK_FULL = 8
ERROR_FAT_TABLE = 9
ERROR_ACCESS_DENIED = 10
PUSHAD_EAX equ [esp+28]
PUSHAD_ECX equ [esp+24]
PUSHAD_EDX equ [esp+20]
PUSHAD_EBX equ [esp+16]
PUSHAD_EBP equ [esp+8]
PUSHAD_ESI equ [esp+4]
PUSHAD_EDI equ [esp+0]
align 4
;******************************************************
; Please do not change this place - variables in text
; Mario79
; START place
;******************************************************
PARTITION_START dd 0x3f
PARTITION_END dd 0
SECTORS_PER_FAT dd 0x1f3a
NUMBER_OF_FATS dd 0x2
SECTORS_PER_CLUSTER dd 0x8
BYTES_PER_SECTOR dd 0x200 ; Note: if BPS <> 512 need lots of changes
ROOT_CLUSTER dd 2 ; first rootdir cluster
FAT_START dd 0 ; start of fat table
ROOT_START dd 0 ; start of rootdir (only fat16)
ROOT_SECTORS dd 0 ; count of rootdir sectors (only fat16)
DATA_START dd 0 ; start of data area (=first cluster 2)
LAST_CLUSTER dd 0 ; last availabe cluster
ADR_FSINFO dd 0 ; used only by fat32
fatRESERVED dd 0x0FFFFFF6
fatBAD dd 0x0FFFFFF7
fatEND dd 0x0FFFFFF8
fatMASK dd 0x0FFFFFFF
fat_type db 0 ; 0=none, 16=fat16, 32=fat32
;***************************************************************************
; End place
; Mario79
;***************************************************************************
cluster dd 0 ; used by file_write,makedir,append
partition_count dd 0 ; partitions found by set_FAT32_variables
longname_sec1 dd 0 ; used by analyze_directory to save 2 previous
longname_sec2 dd 0 ; directory sectors for delete long filename
hd_error dd 0 ; set by wait_for_sector_buffer
hd_setup dd 0
hd_wait_timeout dd 0
cluster_tmp dd 0 ; used by analyze_directory
; and analyze_directory_to_write
file_size dd 0 ; used by file_read
sector_tmp dd 0 ; used by rename,append,file_write
entry_pos dd 0 ; used by rename,append,file_write
old_filesize dd 0 ; used by append
new_filepos dd 0 ; used by append
bytes2write dd 0 ; used by append
cache_search_start dd 0 ; used by find_empty_slot
fat_in_cache dd -1
fat_cache: times 512 db 0
uglobal
Sector512: ; label for dev_hdcd.inc
buffer: times 512 db 0
deltree_buffer: times 512 db 0
endg
iglobal
NewDirEntry1 db ". ",0x10
times 20 db 0
NewDirEntry2 db ".. ",0x10
times 20 db 0
endg
uglobal
dir_entry: times 32 db 0
startpath: times 255 db 0
fat16_root db 0 ; flag for fat16 rootdir
f_del db 0 ; 1=overwrite fat entry
fat_change db 0 ; 1=fat has changed
endg
iglobal
partition_types: ; list of fat16/32 partitions
db 0x04 ; DOS: fat16 <32M
db 0x06 ; DOS: fat16 >32M
db 0x0b ; WIN95: fat32
db 0x0c ; WIN95: fat32, LBA-mapped
db 0x0e ; WIN95: fat16, LBA-mapped
db 0x14 ; Hidden DOS: fat16 <32M
db 0x16 ; Hidden DOS: fat16 >32M
db 0x1b ; Hidden WIN95: fat32
db 0x1c ; Hidden WIN95: fat32, LBA-mapped
db 0x1e ; Hidden WIN95: fat16, LBA-mapped
db 0xc4 ; DRDOS/secured: fat16 <32M
db 0xc6 ; DRDOS/secured: fat16 >32M
db 0xcb ; DRDOS/secured: fat32
db 0xcc ; DRDOS/secured: fat32, LBA-mapped
db 0xce ; DRDOS/secured: fat16, LBA-mapped
db 0xd4 ; Old Multiuser DOS secured: fat16 <32M
db 0xd6 ; Old Multiuser DOS secured: fat16 >32M
partition_types_end:
extended_types: ; list of extended partitions
db 0x05 ; DOS: extended partition
db 0x0f ; WIN95: extended partition, LBA-mapped
db 0xc5 ; DRDOS/secured: extended partition
db 0xd5 ; Old Multiuser DOS secured: extended partition
extended_types_end:
endg
reserve_hd1:
cli
cmp [hd1_status],0
je reserve_ok1
sti
call change_task
jmp reserve_hd1
reserve_ok1:
push eax
mov eax,[0x3000]
shl eax,5
mov eax,[eax+0x3000+4]
mov [hd1_status],eax
pop eax
sti
ret
clear_hd_cache:
push eax ecx edi
mov edi,0x600000
mov ecx,16384
xor eax,eax
cld
rep stosd ; clear hd cache with 0
mov [cache_search_start],eax
mov [fat_in_cache],-1
mov [fat_change],0
pop edi ecx eax
ret
problem_partition db 0 ; used for partitions search
; Partition chain used:
; MBR ; PARTITION2 ; PARTITION3 ; PARTITION4
;==========================================================
; fat16/32 +-- fat16/32 +-- fat16/32 +-- fat16/32 +--
; extended --+ extended --+ extended --+ extended --+
; 0 0 0 0
; 0 0 0 0
; Notes:
; - extended partition need to be in second entry on table
; - it will skip over removed partitions
set_FAT32_variables:
mov [0xfe10],dword 0 ; entries in hd cache
mov [problem_partition],0
call reserve_hd1
call clear_hd_cache
cmp dword [hdpos],0
je problem_hd
pushad
xor ecx,ecx ; partition count
mov edx,-1 ; flag for partition
xor eax,eax ; read MBR
xor ebp,ebp ; extended partition start
new_partition:
test ebp,ebp ; is there extended partition?
jnz extended_already_set ; yes
xchg ebp,eax ; no. set it now
extended_already_set:
add eax,ebp ; mbr=mbr+0, ext_part=ext_start+relat_start
mov ebx,buffer
call hd_read
cmp word [ebx+0x1fe],0xaa55 ; is it valid boot sector?
jnz end_partition_chain
cmp dword [ebx+0x1be+0xc],0 ; skip over empty partition
jz next_partition
push eax ecx
mov edi,partition_types
mov ecx,partition_types_end-partition_types
mov al,[ebx+0x1be+4] ; get partition type
cld
repne scasb ; is partition type ok?
pop ecx eax
jnz next_partition ; no. skip over
inc ecx
cmp ecx,[fat32part] ; is it wanted partition?
jnz next_partition ; no
mov edx,eax ; start sector
add edx,[ebx+0x1be+8] ; add relative start
next_partition:
push ecx
mov edi,extended_types
mov ecx,extended_types_end-extended_types
mov al,[ebx+0x1be+4+16] ; get second partition type
cld
repne scasb ; is it extended partition?
pop ecx
jnz end_partition_chain ; no. end chain
mov eax,[ebx+0x1be+8+16] ; get start of extended partition
test eax,eax ; is there extended partition?
jnz new_partition ; yes. read it
end_partition_chain:
mov [partition_count],ecx
cmp edx,-1 ; found wanted partition?
jnz hd_and_partition_ok ; yes. install it
jmp problem_partition_or_fat
problem_fat_dec_count: ; bootsector is missing or another problem
dec [partition_count] ; remove it from partition_count
problem_partition_or_fat:
popad
problem_hd:
mov [fat_type],0
mov [hd1_status],0 ; free
mov [problem_partition],1
ret
hd_and_partition_ok:
mov eax,edx
mov [PARTITION_START],eax
mov [hd_setup],1
mov ebx,buffer
call hd_read ; read boot sector of partition
mov [hd_setup],0
cmp word [ebx+0x1fe],0xaa55 ; is it valid boot sector?
jnz problem_fat_dec_count
movzx eax,word [ebx+0xe] ; sectors reserved
add eax,[PARTITION_START]
mov [FAT_START],eax ; fat_start = partition_start + reserved
movzx eax,byte [ebx+0xd] ; sectors per cluster
mov [SECTORS_PER_CLUSTER],eax
movzx ecx,word [ebx+0xb] ; bytes per sector
mov [BYTES_PER_SECTOR],ecx
movzx eax,word [ebx+0x11] ; count of rootdir entries (=0 fat32)
mov edx,32
mul edx
dec ecx
add eax,ecx ; round up if not equal count
inc ecx ; bytes per sector
div ecx
mov [ROOT_SECTORS],eax ; count of rootdir sectors
movzx eax,word [ebx+0x16] ; sectors per fat <65536
test eax,eax
jnz fat16_fatsize
mov eax,[ebx+0x24] ; sectors per fat
fat16_fatsize:
mov [SECTORS_PER_FAT],eax
movzx eax,byte [ebx+0x10] ; number of fats
test eax,eax ; if 0 it's not fat partition
jz problem_fat_dec_count
mov [NUMBER_OF_FATS],eax
imul eax,[SECTORS_PER_FAT]
add eax,[FAT_START]
mov [ROOT_START],eax ; rootdir = fat_start + fat_size * fat_count
add eax,[ROOT_SECTORS] ; rootdir sectors should be 0 on fat32
mov [DATA_START],eax ; data area = rootdir + rootdir_size
movzx eax,word [ebx+0x13] ; total sector count <65536
test eax,eax
jnz fat16_total
mov eax,[ebx+0x20] ; total sector count
fat16_total:
add eax,[PARTITION_START]
dec eax
mov [PARTITION_END],eax
inc eax
sub eax,[DATA_START] ; eax = count of data sectors
xor edx,edx
div dword [SECTORS_PER_CLUSTER]
inc eax
mov [LAST_CLUSTER],eax
dec eax ; cluster count
; limits by Microsoft Hardware White Paper v1.03
cmp eax,4085 ; 0xff5
jb problem_fat_dec_count ; fat12 not supported
cmp eax,65525 ; 0xfff5
jb fat16_partition
fat32_partition:
mov eax,[ebx+0x2c] ; rootdir cluster
mov [ROOT_CLUSTER],eax
movzx eax,word [ebx+0x30] ; fs info sector
add eax,[PARTITION_START]
mov [ADR_FSINFO],eax
popad
mov [fatRESERVED],0x0FFFFFF6
mov [fatBAD],0x0FFFFFF7
mov [fatEND],0x0FFFFFF8
mov [fatMASK],0x0FFFFFFF
mov [fat_type],32 ; Fat32
mov [hd1_status],0 ; free
ret
fat16_partition:
xor eax,eax
mov [ROOT_CLUSTER],eax
popad
mov [fatRESERVED],0x0000FFF6
mov [fatBAD],0x0000FFF7
mov [fatEND],0x0000FFF8
mov [fatMASK],0x0000FFFF
mov [fat_type],16 ; Fat16
mov [hd1_status],0 ; free
ret
set_FAT:
;--------------------------------
; input : EAX = cluster
; EDX = value to save
; output : EDX = old value
;--------------------------------
push eax ebx esi
cmp eax,2
jb sfc_error
cmp eax,[LAST_CLUSTER]
ja sfc_error
cmp [fat_type],16
je sfc_1
add eax,eax
sfc_1:
add eax,eax
mov esi,511
and esi,eax ; esi = position in fat sector
shr eax,9 ; eax = fat sector
add eax,[FAT_START]
mov ebx,fat_cache
cmp eax,[fat_in_cache] ; is fat sector already in memory?
je sfc_in_cache ; yes
cmp [fat_change],0 ; is fat changed?
je sfc_no_change ; no
call write_fat_sector ; yes. write it into disk
sfc_no_change:
mov [fat_in_cache],eax ; save fat sector
call hd_read
sfc_in_cache:
cmp [fat_type],16
jne sfc_test32
cmp [f_del],1 ; overwrite previous value?
je sfc_set16 ; yes
cmp word [ebx+esi],0 ; is cluster free?
je sfc_set16 ; yes
mov dword [8*0x100000],0xffffff
mov edx,[ebx+esi] ; get old value
jmp sfc_nonzero
sfc_set16:
xchg [ebx+esi],dx ; save new value and get old value
jmp sfc_write
sfc_test32:
mov eax,[fatMASK]
cmp [f_del],1 ; overwrite previous value?
je sfc_set32 ; yes
test eax,[ebx+esi] ; is cluster free?
je sfc_set32 ; yes
mov dword [8*0x100000],0xffffff
mov edx,[ebx+esi] ; get old value
jmp sfc_nonzero
sfc_set32:
and edx,eax
xor eax,-1 ; mask for high bits
and eax,[ebx+esi] ; get high 4 bits
or eax,edx
mov edx,[ebx+esi] ; get old value
mov [ebx+esi],eax ; save new value
sfc_write:
mov [fat_change],1 ; fat has changed
sfc_nonzero:
and edx,[fatMASK]
sfc_error:
pop esi ebx eax
ret
get_FAT:
;--------------------------------
; input : EAX = cluster
; output : EAX = next cluster
;--------------------------------
push ebx esi
cmp [fat_type],16
je gfc_1
add eax,eax
gfc_1:
add eax,eax
mov esi,511
and esi,eax ; esi = position in fat sector
shr eax,9 ; eax = fat sector
add eax,[FAT_START]
mov ebx,fat_cache
cmp eax,[fat_in_cache] ; is fat sector already in memory?
je gfc_in_cache
cmp [fat_change],0 ; is fat changed?
je gfc_no_change ; no
call write_fat_sector ; yes. write it into disk
gfc_no_change:
mov [fat_in_cache],eax
call hd_read
gfc_in_cache:
mov eax,[ebx+esi]
and eax,[fatMASK]
pop esi ebx
ret
get_free_FAT:
;-----------------------------------------------------------
; input : EAX = # cluster for start the searching
; output : if CARRY=0 EAX = # first cluster found free
; if CARRY=1 disk full
; Note : for more speed need to use fat_cache directly
;-----------------------------------------------------------
push ecx
mov ecx,[LAST_CLUSTER] ; counter for full disk
sub ecx,2
gff_test:
cmp eax,[LAST_CLUSTER] ; if above last cluster start at cluster 2
jbe gff_in_range
mov eax,2
gff_in_range:
push eax
call get_FAT ; get cluster state
test eax,eax ; is it free?
pop eax
je gff_found ; yes
inc eax ; next cluster
dec ecx ; is all checked?
jns gff_test ; no
gff_not_found:
pop ecx ; yes. disk is full
stc
ret
gff_found:
pop ecx
clc
ret
write_fat_sector:
;-----------------------------------------------------------
; write changed fat to disk
;-----------------------------------------------------------
push eax ebx ecx
mov [fat_change],0
mov eax,[fat_in_cache]
cmp eax,-1
jz write_fat_not_used
mov ebx,fat_cache
mov ecx,[NUMBER_OF_FATS]
write_next_fat:
call hd_write
add eax,[SECTORS_PER_FAT]
dec ecx
jnz write_next_fat
write_fat_not_used:
pop ecx ebx eax
ret
analyze_directory:
;-----------------------------------------------------------
; input : EAX = first cluster of the directory
; EBX = pointer to filename
; output : IF CARRY=0 EAX = sector where th file is found
; EBX = pointer in buffer
; [buffer .. buffer+511]
; ECX,EDX,ESI,EDI not changed
; IF CARRY=1 filename not found
; Note : if cluster=0 it's changed to read rootdir
; save 2 previous directory sectors in longname_sec
;-----------------------------------------------------------
push ecx edx esi edi ebx ; ebx = [esp+0]
mov [longname_sec1],0
mov [longname_sec2],0
adr_new_cluster:
mov [cluster_tmp],eax
mov [fat16_root],0
cmp eax,[LAST_CLUSTER]
ja adr_not_found ; too big cluster number, something is wrong
cmp eax,2
jnb adr_data_cluster
mov eax,[ROOT_CLUSTER] ; if cluster < 2 then read rootdir
cmp [fat_type],16
jne adr_data_cluster
mov eax,[ROOT_START]
mov edx,[ROOT_SECTORS]
mov [fat16_root],1 ; flag for fat16 rootdir
jmp adr_new_sector
adr_data_cluster:
sub eax,2
mov edx,[SECTORS_PER_CLUSTER]
imul eax,edx
add eax,[DATA_START]
adr_new_sector:
mov ebx,buffer
call hd_read
mov ecx,512/32 ; count of dir entrys per sector = 16
adr_analyze:
mov edi,[ebx+11] ; file attribute
and edi,0xf
cmp edi,0xf
je adr_long_filename
test edi,0x8 ; skip over volume label
jne adr_long_filename ; Note: label can be same name as file/dir
mov esi,[esp+0] ; filename need to be uppercase
mov edi,ebx
push ecx
mov ecx,11
cld
rep cmpsb ; compare 8+3 filename
pop ecx
je adr_found
adr_long_filename:
add ebx,32 ; position of next dir entry
dec ecx
jnz adr_analyze
mov ecx,[longname_sec1] ; save 2 previous directory sectors
mov [longname_sec1],eax ; for delete long filename
mov [longname_sec2],ecx
inc eax ; next sector
dec edx
jne adr_new_sector
cmp [fat16_root],1 ; end of fat16 rootdir
je adr_not_found
adr_next_cluster:
mov eax,[cluster_tmp]
call get_FAT ; get next cluster
cmp eax,2 ; incorrect fat chain?
jb adr_not_found ; yes
cmp eax,[fatRESERVED] ; is it end of directory?
jb adr_new_cluster ; no. analyse it
adr_not_found:
pop edi edi esi edx ecx ; first edi will remove ebx
stc ; file not found
ret
adr_found:
pop edi edi esi edx ecx ; first edi will remove ebx
clc ; file found
ret
analyze_directory_to_write:
;-----------------------------------------------------------
; input : EAX = first cluster of the directory
; output : IF CARRY=0 EAX = sector where the empty pos is found
; EBX = pointer in buffer
; [buffer .. buffer+511]
; ECX,EDX,ESI,EDI not changed
; IF CARRY=1 disk full or fat corrupted
; Note : if cluster=0 it's changed to read rootdir
;-----------------------------------------------------------
push ecx edx edi
adw_new_cluster:
mov [cluster_tmp],eax
mov [fat16_root],0
cmp eax,[LAST_CLUSTER]
ja adw_not_found ; too big cluster number, something is wrong
cmp eax,2
jnb adw_data_cluster
mov eax,[ROOT_CLUSTER] ; if cluster < 2 then read rootdir
cmp [fat_type],16
jne adw_data_cluster
mov eax,[ROOT_START]
mov edx,[ROOT_SECTORS]
mov [fat16_root],1 ; flag for fat16 rootdir
jmp adw_new_sector
adw_data_cluster:
sub eax,2
mov edx,[SECTORS_PER_CLUSTER]
imul eax,edx
add eax,[DATA_START]
adw_new_sector:
mov ebx,buffer
call hd_read
mov ecx,512/32 ; count of dir entrys per sector = 16
adw_analyze:
cmp byte [ebx],0x00 ; is free entry?
je adw_found ; yes
cmp byte [ebx],0xe5 ; is deleted entry?
je adw_found ; yes
add ebx,32 ; position of next dir entry
dec ecx
jnz adw_analyze
inc eax ; next sector
dec edx
jne adw_new_sector
cmp [fat16_root],1 ; end of fat16 rootdir
je adw_not_found
mov eax,[cluster_tmp]
call get_FAT ; get next cluster
cmp eax,2 ; incorrect fat chain?
jb adw_not_found ; yes
cmp eax,[fatRESERVED] ; is it end of directory?
jb adw_new_cluster ; no. analyse it
mov eax,2 ; this block of code add a new cluster
call get_free_FAT ; for the directory because the directory
jc adw_not_found ; is full
mov edx,[fatEND] ; new end for directory
call set_FAT
push eax ; save new cluster
mov edx,eax
mov eax,[cluster_tmp] ; change last cluster to point new cluster
mov [f_del],1
call set_FAT
mov [f_del],0
mov ecx,-1 ; remove 1 cluster from free disk space
call add_disk_free_space
mov ecx,512/4
xor eax,eax
mov edi,buffer
cld
rep stosd ; clear new directory cluster
pop eax
sub eax,2
mov ecx,[SECTORS_PER_CLUSTER]
imul eax,ecx
add eax,[DATA_START]
mov ebx,buffer
push eax ; save sector number
adw_set_empty_directory:
call hd_write
inc eax ; next sector
dec ecx
jnz adw_set_empty_directory
pop eax
adw_found:
pop edi edx ecx
clc ; free space found
ret
adw_not_found:
pop edi edx ecx
stc ; free space not found
ret
get_data_cluster:
;-----------------------------------------------------------
; input : EAX = cluster
; EBX = pointer to buffer
; EDX = # blocks to read in buffer
; ESI = # blocks to skip over
; output : if CARRY=0 ok EBX/EDX/ESI updated
; if CARRY=1 cluster out of range
; Note : if cluster=0 it's changed to read rootdir
;-----------------------------------------------------------
push eax ecx
mov [fat16_root],0
cmp eax,[LAST_CLUSTER]
ja gdc_error ; too big cluster number, something is wrong
cmp eax,2
jnb gdc_cluster
mov eax,[ROOT_CLUSTER] ; if cluster < 2 then read rootdir
cmp [fat_type],16
jne gdc_cluster
mov eax,[ROOT_START]
mov ecx,[ROOT_SECTORS] ; Note: not cluster size
mov [fat16_root],1 ; flag for fat16 rootdir
jmp gdc_read
gdc_cluster:
sub eax,2
mov ecx,[SECTORS_PER_CLUSTER]
imul eax,ecx
add eax,[DATA_START]
gdc_read:
test esi,esi ; first wanted block
je gdcl1 ; yes, skip count is 0
dec esi
jmp gdcl2
gdcl1:
call hd_read
add ebx,512 ; update pointer
dec edx
gdcl2:
test edx,edx ; is all read?
je out_of_read
inc eax ; next sector
dec ecx
jnz gdc_read
out_of_read:
pop ecx eax
clc
ret
gdc_error:
pop ecx eax
stc
ret
set_data_cluster:
;-----------------------------------------------------------
; input : EAX = cluster
; EBX = pointer to buffer
; output : if CARRY=0 ok
; if CARRY=1 cluster out of range
;-----------------------------------------------------------
push eax ebx edx
cmp eax,[LAST_CLUSTER]
ja sdc_error ; too big cluster number, something is wrong
sub eax,2
jb sdc_error ; don't allow rootdir write
mov edx,[SECTORS_PER_CLUSTER]
imul eax,edx
add eax,[DATA_START]
sdc_write:
call hd_write
add ebx,512 ; update pointer
inc eax
dec edx
jnz sdc_write
pop edx ebx eax
clc
ret
sdc_error:
pop edx ebx eax
stc
ret
get_cluster_of_a_path:
;---------------------------------------------------------
; input : EBX = pointer to a path string
; (example: the path "/files/data/document" become
; "files......data.......document...0"
; '.' = space char
; '0' = char(0) (ASCII=0) !!! )
; output : if (CARRY=1) -> ERROR in the PATH
; if (CARRY=0) -> EAX=cluster
;---------------------------------------------------------
push ebx edx
mov eax,[ROOT_CLUSTER]
mov edx,ebx
search_end_of_path:
cmp byte [edx],0
je found_end_of_path
inc edx ; '/'
mov ebx,edx
call analyze_directory
jc directory_not_found
mov eax,[ebx+20-2] ; read the HIGH 16bit cluster field
mov ax,[ebx+26] ; read the LOW 16bit cluster field
and eax,[fatMASK]
add edx,11 ; 8+3 (name+extension)
jmp search_end_of_path
found_end_of_path:
pop edx ebx
clc ; no errors
ret
directory_not_found:
pop edx ebx
stc ; errors occour
ret
bcd2bin:
;----------------------------------
; input : AL=BCD number (eg. 0x11)
; output : AH=0
; AL=decimal number (eg. 11)
;----------------------------------
xor ah,ah
shl ax,4
shr al,4
aad
ret
get_date_for_file:
;-----------------------------------------------------
; Get date from CMOS and pack day,month,year in AX
; DATE bits 0..4 : day of month 0..31
; 5..8 : month of year 1..12
; 9..15 : count of years from 1980
;-----------------------------------------------------
mov al,0x7 ;day
out 0x70,al
in al,0x71
call bcd2bin
ror eax,5
mov al,0x8 ;month
out 0x70,al
in al,0x71
call bcd2bin
ror eax,4
mov al,0x9 ;year
out 0x70,al
in al,0x71
call bcd2bin
add ax,20 ;because CMOS return only the two last
;digit (eg. 2000 -> 00 , 2001 -> 01) and we
rol eax,9 ;need the difference with 1980 (eg. 2001-1980)
ret
get_time_for_file:
;-----------------------------------------------------
; Get time from CMOS and pack hour,minute,second in AX
; TIME bits 0..4 : second (the low bit is lost)
; 5..10 : minute 0..59
; 11..15 : hour 0..23
;-----------------------------------------------------
mov al,0x0 ;second
out 0x70,al
in al,0x71
call bcd2bin
ror eax,6
mov al,0x2 ;minute
out 0x70,al
in al,0x71
call bcd2bin
ror eax,6
mov al,0x4 ;hour
out 0x70,al
in al,0x71
call bcd2bin
rol eax,11
ret
set_current_time_for_entry:
;-----------------------------------------------------
; Set current time/date for file entry
; input : ebx = file entry pointer
;-----------------------------------------------------
push eax
call get_time_for_file ; update files date/time
mov [ebx+22],ax
call get_date_for_file
mov [ebx+24],ax
pop eax
ret
makedir:
;-----------------------------------------------------
; input : eax = directory name
; edx = path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 8 - disk full
; 10 - access denied
; Note : can only make one directory at time
;-----------------------------------------------------
cmp [fat_type],0
jnz make_dir_fat_ok
mov eax,ERROR_UNKNOWN_FS
ret
make_dir_fat_ok:
; call reserve_hd1
pushad
mov ebx,edx
call get_cluster_of_a_path
jnc make_dir_found_path
make_dir_path_not_found:
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
mov eax,ERROR_FILE_NOT_FOUND
ret
make_dir_disk_full:
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
mov eax,ERROR_DISK_FULL
ret
make_dir_already_exist:
mov eax,[cluster] ; directory cluster
xor edx,edx ; free
mov [f_del],1
call set_FAT
mov [f_del],0
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
mov eax,ERROR_ACCESS_DENIED
ret
make_dir_found_path:
cmp eax,[ROOT_CLUSTER]
jnz make_dir_not_root
xor eax,eax
make_dir_not_root:
mov ecx,eax ; directorys start cluster
mov word [NewDirEntry2+26],cx ; 16 bits low of cluster
shr ecx,16
mov word [NewDirEntry2+20],cx ; 16 bits high of cluster (=0 fat16)
push eax ; save parent directory cluster
mov eax,2
call get_free_FAT
mov [cluster],eax ; first free cluster
pop eax
jc make_dir_disk_full
push eax
mov eax,[cluster] ; directory cluster
mov edx,[fatEND] ; end for directory
call set_FAT
pop eax
mov ebx,PUSHAD_EAX ; dir name
push eax
call analyze_directory ; check if directory already exist
pop eax
jnc make_dir_already_exist ; need to free allocated cluster!
call analyze_directory_to_write
jc make_dir_already_exist ; need to free allocated cluster!
mov esi,PUSHAD_EAX ; dir name
mov edi,ebx ; pointer in buffer
mov ecx,11
cld
rep movsb
mov dword [ebx+28],0 ; dir size is always 0
mov ecx,[cluster]
mov [ebx+26],cx ; 16 bits low of cluster
mov word [NewDirEntry1+26],cx
shr ecx,16
mov [ebx+20],cx ; 16 bits high of cluster (=0 fat16)
mov word [NewDirEntry1+20],cx
mov byte [ebx+11],0x10 ; attribute = directory
call set_current_time_for_entry
mov ecx,[ebx+22]
mov dword [NewDirEntry1+22],ecx
mov dword [NewDirEntry2+22],ecx
mov ebx,buffer ; save the directory name,length,cluster
call hd_write
mov ecx,512/4
xor eax,eax
mov edi,buffer
cld
rep stosd ; clear new directory cluster
mov eax,[cluster] ; new directory cluster
sub eax,2
mov edx,[SECTORS_PER_CLUSTER]
imul eax,edx
add eax,[DATA_START]
mov ebx,buffer
add eax,edx ; start from last sector
dir_set_empty_directory:
dec eax ; next sector
cmp edx,1 ; is first directory sector?
jnz not_first_sector ; no. write empty sector
mov esi,NewDirEntry1
mov edi,buffer
mov ecx,64/4
cld
rep movsd ; copy 2 first directory entrys "." and ".."
not_first_sector:
call hd_write
dec edx
jnz dir_set_empty_directory
mov ecx,-1 ; remove 1 cluster from free disk space
call add_disk_free_space
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
xor eax,eax
ret
removedir:
;-----------------------------------------------------
; input : eax = file/directory name
; edx = path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 10 - access denied
;-----------------------------------------------------
cmp [fat_type],0
jnz remove_dir_fat_ok
mov eax,ERROR_UNKNOWN_FS
ret
remove_dir_fat_ok:
; call reserve_hd1
push edi
mov edi,1 ; allow directory remove
call file_delete
pop edi
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
ret
add_disk_free_space:
;-----------------------------------------------------
; input : ecx = cluster count
; Note : negative = remove clusters from free space
; positive = add clusters to free space
;-----------------------------------------------------
test ecx,ecx ; no change
je add_dfs_no
cmp [fat_type],32 ; free disk space only used by fat32
jne add_dfs_no
push eax ebx
mov eax,[ADR_FSINFO]
mov ebx,buffer
call hd_read
cmp dword [ebx+0x1fc],0xaa550000 ; check sector id
jne add_not_fs
add [ebx+0x1e8],ecx
call hd_write
add_not_fs:
pop ebx eax
add_dfs_no:
ret
file_append:
;-----------------------------------------------------
; input : eax = file name
; edx = path
; ecx = pointer to buffer
; ebx = bytes to write (0 = truncate file)
; esi = start position (-1 = end of file)
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 6 - end of file
; 8 - disk full
; 9 - fat table corrupted
; 10 - access denied
; ebx = bytes written
;-----------------------------------------------------
cmp [fat_type],0
jnz append_fat_ok
mov eax,ERROR_UNKNOWN_FS
ret
append_fat_ok:
; call reserve_hd1
pushad
mov ebx,edx
call get_cluster_of_a_path
jc append_not_found
mov ebx,PUSHAD_EAX ; file name
call analyze_directory
jc append_not_found
mov [sector_tmp],eax
mov [entry_pos],ebx
test byte [ebx+11],0x10 ; is it directory?
jnz append_access ; yes
mov ecx,[ebx+28] ; file size
mov edi,PUSHAD_ESI ; write position
cmp edi,-1 ; -1 = eof
jnz append_inside_file
mov edi,ecx ; file size
append_inside_file:
cmp edi,ecx ; start above old file size?
ja append_eof ; yes
mov [old_filesize],ecx
mov [new_filepos],edi
mov ecx,PUSHAD_EBX ; bytes to write
test ecx,ecx ; truncate?
jz append_truncate ; yes
mov [bytes2write],ecx ; bytes to write
mov esi,PUSHAD_ECX ; pointer to buffer
mov eax,[ebx+20-2] ; FAT entry
mov ax,[ebx+26]
and eax,[fatMASK]
jnz append_find_pos ; first cluster <> 0
mov eax,2
call get_free_FAT
jc append_disk_full
mov ecx,eax ; set files first cluster
mov [ebx+26],cx ; 16 bits low of cluster
shr ecx,16
mov [ebx+20],cx ; 16 bits high of cluster (=0 fat16)
mov edx,[fatEND] ; new end for cluster chain
call set_FAT
push eax ; save first cluster
mov eax,[sector_tmp]
mov ebx,buffer
call hd_write ; write new file entry back to disk
pop eax
append_remove_free:
mov ecx,-1 ; remove 1 cluster from free disk space
call add_disk_free_space ; Note: uses buffer
append_found_cluster:
mov [cluster],eax
sub eax,2
mov ecx,[SECTORS_PER_CLUSTER]
imul eax,ecx
add eax,[DATA_START]
xor edi,edi
append_new_sector:
push ecx
mov ecx,[bytes2write] ; bytes left in buffer
mov ebx,512
sub ebx,edi ; bytes left in sector
cmp ecx,ebx
jb append_bytes_ok
mov ecx,ebx
append_bytes_ok:
cmp ecx,512 ; overwrite full sector?
jz append_full_sector ; yes
mov ebx,buffer ; overwrite part of sector
call hd_read ; read old sector
append_full_sector:
sub [bytes2write],ecx
add [new_filepos],ecx
add edi,buffer
cld
rep movsb
pop ecx
mov ebx,buffer
call hd_write
cmp [bytes2write],0 ; is all done?
jz append_done
xor edi,edi
inc eax
dec ecx
jnz append_new_sector
mov eax,[cluster]
call get_FAT
cmp eax,2
jb append_fat
cmp eax,[LAST_CLUSTER]
jbe append_found_cluster
append_alloc_cluster:
mov eax,2 ; ToDo: use temp array to keep track
call get_free_FAT ; of last free cluster
jc append_disk_full
push eax ; save new cluster
mov edx,[fatEND] ; new end for cluster chain
call set_FAT
mov edx,eax
mov eax,[cluster]
mov [f_del],1
call set_FAT ; update previous cluster
mov [f_del],0
pop eax
jmp append_remove_free
append_find_pos:
call find_filepos
mov [cluster],ebx
jnc append_new_sector
test edi,edi
jz append_alloc_cluster
append_fat:
mov eax,ERROR_FAT_TABLE
jmp append_ret_code
append_disk_full:
mov eax,ERROR_DISK_FULL
jmp append_ret_code
append_done:
xor eax,eax
append_ret_code:
mov PUSHAD_EAX,eax ; return code
mov eax,[sector_tmp] ; update directory entry
mov ebx,buffer
call hd_read
mov ebx,[entry_pos]
mov ecx,[new_filepos]
cmp ecx,[old_filesize] ; is file pos above old size?
jbe append_size_ok ; no
mov [ebx+28],ecx ; new file size
append_size_ok:
call set_current_time_for_entry
mov ebx,buffer
call hd_write ; write new file entry back to disk
sub ecx,PUSHAD_ESI ; start position
mov PUSHAD_EBX,ecx ; bytes written
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
ret
append_eof:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_END_OF_FILE
ret
append_not_found:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
append_access:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_ACCESS_DENIED
ret
append_truncate:
mov edx,[ebx+20-2] ; FAT entry
mov dx,[ebx+26]
and edx,[fatMASK]
mov [ebx+28],edi ; set new file size
test edi,edi ; 0 length file?
jnz truncate_save_size ; no
mov [ebx+20],di ; FAT entry = 0
mov [ebx+26],di
truncate_save_size:
call set_current_time_for_entry
mov ebx,buffer
call hd_write
mov eax,edx ; first cluster
test edi,edi ; 0 length file?
jz truncate_clear_chain
imul esi,[SECTORS_PER_CLUSTER],512 ; esi = cluster size in bytes
truncate_new_cluster:
cmp eax,2 ; incorrect fat chain?
jb truncate_eof ; yes
cmp eax,[fatRESERVED] ; is it end of file?
jnb truncate_eof ; yes
sub edi,esi
jbe truncate_pos_found
call get_FAT ; get next cluster
jmp truncate_new_cluster
truncate_pos_found:
mov edx,[fatEND] ; new end for cluster chain
mov [f_del],1
call set_FAT
mov [f_del],0
mov eax,edx ; clear rest of chain
truncate_clear_chain:
call clear_cluster_chain
truncate_eof:
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
xor ebx,ebx
xor eax,eax
ret
find_filepos:
;-----------------------------------------------------
; input : eax = first cluster
; edi = bytes to skip over (start position)
; output : if CARRY=0 file position found
; if CARRY=1 end of file found
; eax = current file sector
; ebx = last cluster
; ecx = sector count in last cluster
; edi = bytes to skip over (sector position)
;-----------------------------------------------------
push esi
mov ecx,[SECTORS_PER_CLUSTER]
imul esi,ecx,512 ; esi = cluster size in bytes
mov ebx,eax
filepos_new_cluster:
cmp eax,2 ; incorrect fat chain?
jb filepos_eof ; yes
cmp eax,[fatRESERVED] ; is it end of file?
jnb filepos_eof ; yes
mov ebx,eax
cmp edi,esi ; skip over full cluster?
jb filepos_cluster_ok ; no
sub edi,esi
call get_FAT ; get next cluster
jmp filepos_new_cluster
filepos_cluster_ok:
sub eax,2
imul eax,ecx
add eax,[DATA_START]
filepos_new_sector:
cmp edi,512 ; skip over full sector?
jb filepos_sector_ok ; no
sub edi,512
inc eax
dec ecx
jnz filepos_new_sector
filepos_eof:
pop esi
stc
ret
filepos_sector_ok:
pop esi
clc
ret
file_write:
;--------------------------------------------------------------------------
; INPUT : user-reg register-in-this meaning symbol-in-this-routine
;
; EAX EDI system call to write /
; EBX EAX (PAR0) pointer to file-name PAR0
; EDX ECX (PAR1) pointer to buffer PAR1
; ECX EBX (PAR2) file size PAR2
; ESI EDX (PAR3) pointer to path PAR3
;
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 8 - disk full
; 10 - access denied
;--------------------------------------------------------------------------
cmp [fat_type],0
jnz fat_ok_for_writing
mov eax,ERROR_UNKNOWN_FS
ret
fat_ok_for_writing:
; call reserve_hd1
pushad
xor edi,edi ; don't allow directory remove
call file_delete ; try to delete the file first
test eax,eax
jz old_deleted ; deleted ok
cmp eax,ERROR_FILE_NOT_FOUND
jnz exit_write_access ; it exist but can't delete
old_deleted:
mov ebx,PUSHAD_EDX
call get_cluster_of_a_path
jnc found_directory_for_writing
exit_writing_with_error:
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
mov eax,ERROR_FILE_NOT_FOUND
ret
exit_writing_disk_full_clear:
mov eax,[sector_tmp]
mov ebx,buffer
call hd_read ; read directory sector
mov edx,[entry_pos]
mov byte [edx],0xe5 ; mark as deleted
call hd_write
mov eax,[edx+20-2] ; FAT entry
mov ax,[edx+26]
and eax,[fatMASK]
call clear_cluster_chain
exit_writing_disk_full:
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
mov eax,ERROR_DISK_FULL
ret
exit_write_access:
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
mov eax,ERROR_ACCESS_DENIED
ret
found_directory_for_writing:
call analyze_directory_to_write
jc exit_writing_disk_full
mov [sector_tmp],eax
mov [entry_pos],ebx
push eax ; save directory sector
mov eax,2
call get_free_FAT
mov [cluster],eax ; first free cluster
pop eax
jc exit_writing_disk_full
mov esi,PUSHAD_EAX ; file name
mov edi,ebx ; pointer in buffer
mov ecx,11
cld
rep movsb
mov esi,PUSHAD_EBX ; file size (bytes left)
mov [ebx+28],esi ; file size
mov ecx,[cluster]
mov [ebx+26],cx ; 16 bits low of cluster
shr ecx,16
mov [ebx+20],cx ; 16 bits high of cluster (=0 fat16)
mov byte [ebx+11],0x20 ; attribute = archive
call set_current_time_for_entry
mov ebx,buffer ; save the directory name,length,cluster
call hd_write
imul edi,[SECTORS_PER_CLUSTER],512 ; edi = cluster size in bytes
xor ecx,ecx ; cluster count
mov ebx,PUSHAD_ECX ; ebx = buffer
hd_new_block_write:
mov eax,[cluster] ; eax = block
call set_data_cluster
sub esi,edi ; sub wrote bytes
jbe file_saved_OK ; end if all done
add ebx,edi ; update buffer position
inc eax
call get_free_FAT ; next free in FAT
jc exit_writing_disk_full_clear
mov edx,eax
xchg eax,[cluster] ; get old cluster and save new cluster
call set_FAT ; add it in cluster chain
dec ecx ; update cluster count
jmp hd_new_block_write
file_saved_OK:
mov edx,[fatEND] ; new end for cluster chain
call set_FAT
dec ecx ; update cluster count
call add_disk_free_space ; remove clusters from free disk space
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
xor eax,eax
ret
file_read:
;--------------------------------------------------------------------------
; INPUT : user-register register-in-this meaning symbol-in-this
;
; EAX EDI system call to write /
; EBX EAX (PAR0) pointer to file-name PAR0
; EDX ECX (PAR1) pointer to buffer PAR1
; ECX EBX (PAR2) vt file blocks to read PAR2
; ESI EDX (PAR3) pointer to path PAR3
; EDI ESI vt first 512 block to read
; EDI if 0 - read root
;
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 6 - end of file
; 9 - fat table corrupted
; ebx = size of file/directory
;--------------------------------------------------------------------------
cmp [fat_type],0
jnz fat_ok_for_reading
xor ebx,ebx
mov eax,ERROR_UNKNOWN_FS
mov [hd1_status], ebx
ret
fat_ok_for_reading:
; call reserve_hd1
pushad
mov ebx,edx
call get_cluster_of_a_path
jc file_to_read_not_found
test edi,edi ; read rootdir
jne no_read_root
xor eax,eax
call get_dir_size ; return rootdir size
mov [file_size],eax
mov eax,[ROOT_CLUSTER]
jmp file_read_start
no_read_root:
mov ebx,PUSHAD_EAX ; file name
call analyze_directory
jc file_to_read_not_found
mov eax,[ebx+28] ; file size
test byte [ebx+11],0x10 ; is it directory?
jz read_set_size ; no
mov eax,[ebx+20-2] ; FAT entry
mov ax,[ebx+26]
and eax,[fatMASK]
call get_dir_size
read_set_size:
mov [file_size],eax
mov eax,[ebx+20-2] ; FAT entry
mov ax,[ebx+26]
and eax,[fatMASK]
file_read_start:
mov ebx,PUSHAD_ECX ; pointer to buffer
mov edx,PUSHAD_EBX ; file blocks to read
mov esi,PUSHAD_ESI ; first 512 block to read
file_read_new_cluster:
call get_data_cluster
jc file_read_eof ; end of file or cluster out of range
test edx,edx ; is all read?
je file_read_OK ; yes
call get_FAT ; get next cluster
cmp eax,[fatRESERVED] ; end of file
jnb file_read_eof
cmp eax,2 ; incorrect fat chain
jnb file_read_new_cluster
popad
mov [hd1_status],0
mov ebx,[file_size]
mov eax,ERROR_FAT_TABLE
ret
file_read_eof:
popad
mov [hd1_status],0
mov ebx,[file_size]
mov eax,ERROR_END_OF_FILE
ret
file_read_OK:
popad
mov [hd1_status],0
mov ebx,[file_size]
xor eax,eax
ret
file_to_read_not_found:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_dir_size:
;-----------------------------------------------------
; input : eax = first cluster (0=rootdir)
; output : eax = directory size in bytes
;-----------------------------------------------------
push edx
xor edx,edx ; count of directory clusters
test eax,eax
jnz dir_size_next
mov eax,[ROOT_SECTORS]
shl eax,9 ; fat16 rootdir size in bytes
cmp [fat_type],16
je dir_size_ret
mov eax,[ROOT_CLUSTER]
dir_size_next:
cmp eax,2 ; incorrect fat chain
jb dir_size_end
cmp eax,[fatRESERVED] ; end of directory
ja dir_size_end
call get_FAT ; get next cluster
inc edx
jmp dir_size_next
dir_size_end:
imul eax,[SECTORS_PER_CLUSTER],512 ; cluster size in bytes
imul eax,edx
dir_size_ret:
pop edx
ret
file_delete:
;-----------------------------------------------------
; input : eax = file/directory name
; edx = path
; edi = 1 - allow directory remove else don't remove directory
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 10 - access denied
;-----------------------------------------------------
cmp [fat_type],0
jnz file_del_fat_ok
mov eax,ERROR_UNKNOWN_FS
ret
file_del_fat_ok:
pushad
mov ebx,edx
call get_cluster_of_a_path
jc file_to_delete_not_found
mov ebx,PUSHAD_EAX ; file/directory name
call analyze_directory
jc file_to_delete_not_found
test byte [ebx+11],0x10 ; is it directory?
jz delete_notdir ; no. it's file
cmp edi,1 ; allow directory remove
jnz delete_no_access ; no
push eax ; save directory sector
mov eax,[ebx+20-2] ; first cluster of file
mov ax,[ebx+26] ; 0 length files start cluster = 0
and eax,[fatMASK]
xor ebp,ebp ; counter for directory deepnes
call clear_directory
pop eax
jc delete_no_access
push ebx ; save directory pointer in buffer
mov ebx,buffer
call hd_read ; read directory sector
pop ebx
delete_notdir:
call delete_entry_name
mov eax,ecx ; first cluster of file
call clear_cluster_chain
popad
xor eax,eax
ret
delete_no_access:
popad
mov eax,ERROR_ACCESS_DENIED
ret
file_to_delete_not_found:
popad
mov eax,ERROR_FILE_NOT_FOUND
ret
clear_cluster_chain:
;-----------------------------------------------------
; input : eax = first cluster
;-----------------------------------------------------
push eax ecx edx
xor ecx,ecx ; cluster count
mov [f_del],1 ; delete on
clean_new_chain:
cmp eax,[LAST_CLUSTER] ; end of file
ja delete_OK
cmp eax,2 ; unfinished fat chain or zero length file
jb delete_OK
cmp eax,[ROOT_CLUSTER] ; don't remove root cluster
jz delete_OK
xor edx,edx
call set_FAT ; clear fat entry
inc ecx ; update cluster count
mov eax,edx ; old cluster
jmp clean_new_chain
delete_OK:
call add_disk_free_space ; add clusters to free disk space
mov [f_del],0
pop edx ecx eax
ret
clear_directory:
;-----------------------------------------------------
; input : eax = directory cluster
; ebp = directory deepnes
; Note : use recursive call
;-----------------------------------------------------
pushad
inc ebp
cmp ebp,64 ; if over 63 directory deep
jnb clear_error ; something must be wrong
clear_new_cluster:
cmp eax,[LAST_CLUSTER]
ja clear_end
cmp eax,[ROOT_CLUSTER] ; don't remove root cluster
jz clear_end
mov esi,eax ; esi = current directory cluster
sub eax,2
jb clear_end
mov ecx,[SECTORS_PER_CLUSTER]
imul eax,ecx
add eax,[DATA_START]
clear_new_sector:
mov edi,eax ; edi = current directory sector
mov ebx,deltree_buffer
call hd_read
mov edx,512/32 ; count of dir entrys per sector = 16
clear_analyze:
mov al,[ebx+11] ; file attribute
and al,0xf
cmp al,0xf
je clear_long_filename
cmp byte [ebx],'.' ; parent or current directory
je clear_next_entry
cmp byte [ebx],0xe5 ; deleted
je clear_next_entry
cmp byte [ebx],0 ; empty
je clear_write_last
;je clear_next_entry
mov eax,[ebx+20-2] ; first cluster of entry
mov ax,[ebx+26]
and eax,[fatMASK]
test byte [ebx+11],0x10 ; is it directory?
jz clear_file ; no
push eax ebx
mov eax,edi
mov ebx,deltree_buffer ; save buffer over recursive call
call hd_write ; write directory sector to disk
pop ebx eax
call clear_directory ; recursive call !!!
jc clear_error ; exit if error found
push eax ebx
mov eax,edi
mov ebx,deltree_buffer
call hd_read ; read directory sector again
pop ebx eax
clear_file:
call clear_cluster_chain
clear_long_filename:
mov byte [ebx],0xe5
clear_next_entry:
add ebx,32 ; position of next dir entry
dec edx
jnz clear_analyze
mov eax,edi
mov ebx,deltree_buffer
call hd_write ; write directory sector to disk
inc eax ; next sector
dec ecx
jnz clear_new_sector
mov eax,esi
call get_FAT ; get next cluster
jmp clear_new_cluster ; clear it
clear_write_last:
mov eax,edi
mov ebx,deltree_buffer
call hd_write ; write directory sector to disk
clear_end:
popad
clc
ret
clear_error:
popad
stc
ret
delete_entry_name:
;-----------------------------------------------------
; input : eax = directory sector
; ebx = directory pointer in buffer
; longname_sec = 2 previous directory sectors
; output : ecx = first cluster
; change : eax,ebx,edx
;-----------------------------------------------------
mov byte [ebx],0xe5
mov ecx,[ebx+20-2] ; first cluster of file
mov cx,[ebx+26] ; 0 length files start cluster = 0
and ecx,[fatMASK]
delete_empty:
sub ebx,32
cmp ebx,buffer
jnb delete_test_long
mov ebx,buffer
call hd_write ; write directory sector back
xor eax,eax
xchg eax,[longname_sec2]
xchg eax,[longname_sec1]
test eax,eax ; is there previous directory sector?
jz delete_name_end ; no
mov ebx,buffer
call hd_read ; read previous sector
mov ebx,buffer+0x1e0 ; start from last entry
delete_test_long:
mov dh,[ebx+11] ; file attribute
and dh,0xf
cmp dh,0xf
jne delete_write_buffer
cmp byte [ebx],0x40 ; end of long dir entry?
mov byte [ebx],0xe5
jb delete_empty
delete_write_buffer:
mov ebx,buffer
call hd_write ; write directory sector back
delete_name_end:
ret
rename:
;-----------------------------------------------------------
; input : eax = source directory name
; edx = source path
; ebx = dest directory name
; edi = dest path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 8 - disk full
; 10 - access denied
;-----------------------------------------------------------
cmp [fat_type],0
jnz fat_ok_for_rename
mov eax,ERROR_UNKNOWN_FS
ret
fat_ok_for_rename:
; call reserve_hd1
pushad
mov ebx,edx ; source path
call get_cluster_of_a_path
jc rename_entry_not_found
mov ebx,PUSHAD_EAX ; source directory name
call analyze_directory
jc rename_entry_not_found
mov [sector_tmp],eax ; save source sector
mov [entry_pos],ebx
mov esi,ebx
mov edi,dir_entry
mov ecx,32/4
cld
rep movsd ; save entry
mov ebx,PUSHAD_EDI ; dest path
call get_cluster_of_a_path
jc rename_entry_not_found
mov edx,eax ; save dest directory cluster
mov ebx,PUSHAD_EBX ; dest directory name
push [longname_sec1]
push [longname_sec2]
call analyze_directory ; check if entry already exist
pop [longname_sec2]
pop [longname_sec1]
jnc rename_entry_already_exist
mov eax,edx
call analyze_directory_to_write
jc rename_disk_full
mov esi,dir_entry
mov edi,ebx
mov ecx,32/4
cld
rep movsd ; copy entry
mov esi,PUSHAD_EBX ; dest directory name
mov edi,ebx
mov ecx,11
rep movsb ; copy name
mov ebx,buffer ; save the directory name,length,cluster
call hd_write
test byte [dir_entry+11],0x10 ; is it directory?
jz rename_not_dir ; no
mov eax,[dir_entry+20-2] ; FAT entry
mov ax,[dir_entry+26]
and eax,[fatMASK]
call change_2dot_cluster
rename_not_dir:
mov eax,[sector_tmp]
mov ebx,buffer
call hd_read ; read source directory sector
mov ebx,[entry_pos]
call delete_entry_name
popad
call update_disk ; write all of cache and fat to hd
mov [hd1_status],0
xor eax,eax
ret
rename_entry_not_found:
popad
mov [hd1_status],0
mov eax,ERROR_FILE_NOT_FOUND
ret
rename_entry_already_exist:
popad
mov [hd1_status],0
mov eax,ERROR_ACCESS_DENIED
ret
rename_disk_full:
popad
mov [hd1_status],0
mov eax,ERROR_DISK_FULL
ret
change_2dot_cluster:
;-----------------------------------------------------------
; input : eax = directory cluster
; edx = value to save
; change : eax,ebx,edx
;-----------------------------------------------------------
cmp eax,[LAST_CLUSTER]
ja not_2dot ; too big cluster number, something is wrong
sub eax,2
jb not_2dot
imul eax,[SECTORS_PER_CLUSTER]
add eax,[DATA_START]
mov ebx,buffer
call hd_read
cmp dword [ebx+32],'.. '
jnz not_2dot
cmp edx,[ROOT_CLUSTER] ; is rootdir cluster?
jne not_2dot_root
xor edx,edx ; yes. set it zero
not_2dot_root:
mov [ebx+32+26],dx ; 16 bits low of cluster
shr edx,16
mov [ebx+32+20],dx ; 16 bits high of cluster (=0 fat16)
call hd_write
not_2dot:
ret
get_filesize:
;-----------------------------------------------------------
; input : eax = file name
; edx = path
; edi = if 0 - read rootdir else normal dir/file size
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; ebx = file size
;-----------------------------------------------------------
cmp [fat_type],0
jnz get_filesize_fat_ok
xor ebx,ebx
mov eax,ERROR_UNKNOWN_FS
ret
get_filesize_fat_ok:
; call reserve_hd1
pushad
xor eax,eax
test edi,edi ; is read rootdir?
je get_filesize_dirsize ; yes
get_filesize_no_root:
mov ebx,edx
call get_cluster_of_a_path
jc get_filesize_not_found
mov ebx,PUSHAD_EAX ; file name
call analyze_directory
jc get_filesize_not_found
mov eax,[ebx+28] ; file size
test byte [ebx+11],0x10 ; is it directory?
jz get_filesize_set_size ; no
mov eax,[ebx+20-2] ; FAT entry
mov ax,[ebx+26]
and eax,[fatMASK]
get_filesize_dirsize:
call get_dir_size
get_filesize_set_size:
mov PUSHAD_EBX,eax
popad
mov [hd1_status],0
xor eax,eax
ret
get_filesize_not_found:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_fileattr:
;-----------------------------------------------------------
; input : eax = file name
; edx = path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; ebx = file attribute
;-----------------------------------------------------------
cmp [fat_type],0
jnz get_fileattr_fat_ok
xor ebx,ebx
mov eax,ERROR_UNKNOWN_FS
ret
get_fileattr_fat_ok:
; call reserve_hd1
pushad
mov ebx,edx
call get_cluster_of_a_path
jc get_fileattr_not_found
mov ebx,PUSHAD_EAX ; file name
call analyze_directory
jc get_fileattr_not_found
movzx eax,byte [ebx+11] ; file attribute
mov PUSHAD_EBX,eax
popad
mov [hd1_status],0
xor eax,eax
ret
get_fileattr_not_found:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_filedate:
;-----------------------------------------------------------
; input : eax = file name
; edx = path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; ebx = file date/time
; bits 31..25 = year-1980
; bits 24..21 = month
; bits 20..16 = day
; bits 15..11 = hour
; bits 10..5 = minute
; bits 4..0 = second/2
;-----------------------------------------------------------
cmp [fat_type],0
jnz get_filedate_fat_ok
xor ebx,ebx
mov eax,ERROR_UNKNOWN_FS
ret
get_filedate_fat_ok:
; call reserve_hd1
pushad
mov ebx,edx
call get_cluster_of_a_path
jc get_filedate_not_found
mov ebx,PUSHAD_EAX ; file name
call analyze_directory
jc get_filedate_not_found
mov eax,[ebx+22] ; file date/time
mov PUSHAD_EBX,eax
popad
mov [hd1_status],0
xor eax,eax
ret
get_filedate_not_found:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_hd_info:
;-----------------------------------------------------------
; output : eax = 0 - ok
; 3 - unknown FS
; edx = cluster size in bytes
; ebx = total clusters on disk
; ecx = free clusters on disk
;-----------------------------------------------------------
cmp [fat_type],0
jnz info_fat_ok
xor edx,edx
xor ebx,ebx
xor ecx,ecx
mov eax,ERROR_UNKNOWN_FS
ret
info_fat_ok:
; call reserve_hd1
xor ecx,ecx ; count of free clusters
mov eax,2
mov ebx,[LAST_CLUSTER]
info_cluster:
push eax
call get_FAT ; get cluster info
test eax,eax ; is it free?
jnz info_used ; no
inc ecx
info_used:
pop eax
inc eax
cmp eax,ebx ; is above last cluster?
jbe info_cluster ; no. test next cluster
dec ebx ; cluster count
imul edx,[SECTORS_PER_CLUSTER],512 ; cluster size in bytes
mov [hd1_status],0
xor eax,eax
ret
update_disk:
;-----------------------------------------------------------
; write changed fat and cache to disk
;-----------------------------------------------------------
cmp [fat_change],0 ; is fat changed?
je upd_no_change
call write_fat_sector
upd_no_change:
call write_cache
ret
;**************************************************************************
;
; 0x600008 - first entry in cache list
;
; +0 - lba sector
; +4 - state of cache sector
; 0 = empty
; 1 = used for read ( same as in hd )
; 2 = used for write ( differs from hd )
;
; +65536 - cache entries
;
;**************************************************************************
hd_read:
;-----------------------------------------------------------
; input : eax = block to read
; ebx = destination
;-----------------------------------------------------------
push ecx esi edi ; scan cache
mov ecx,cache_max ; entries in cache
mov esi,0x600000+8
mov edi,1
hdreadcache:
cmp dword [esi+4],0 ; empty
je nohdcache
cmp [esi],eax ; correct sector
je yeshdcache
nohdcache:
add esi,8
inc edi
dec ecx
jnz hdreadcache
call find_empty_slot ; ret in edi
call wait_for_hd_idle
push eax edx
cli
xor eax,eax
mov edx,[hdbase]
inc edx
out dx,al ; ATAFeatures ðåãèñòð "îñîáåÃÃîñòåé"
inc edx
inc eax
out dx,al ; ATASectorCount ñ÷åò÷èê ñåêòîðîâ
inc edx
mov eax,[esp+4]
out dx,al ; ATASectorNumber ðåãèñòð Ãîìåðà ñåêòîðÃ
shr eax,8
inc edx
out dx,al ; ATACylinder Ãîìåð öèëèÃäðà (ìëà äøèé áà éò)
shr eax,8
inc edx
out dx,al ; Ãîìåð öèëèÃäðà (ñòà ðøèé áà éò)
shr eax,8
inc edx
and al,1+2+4+8
add al,byte [hdid]
add al,128+64+32
out dx,al ; Ãîìåð ãîëîâêè/Ãîìåð äèñêÃ
inc edx
mov al,20h
out dx,al ; ATACommand ðåãèñòð êîìà Ãä
sti
call wait_for_sector_buffer
cmp [hd_error],0
jne hd_read_error
cli
push edi
shl edi,9
add edi,0x600000+65536
mov ecx,256
mov edx,[hdbase]
cld
rep insw
pop edi
sti
pop edx eax
blok_read_2:
lea esi,[edi*8+0x600000]
mov [esi],eax ; sector number
mov dword [esi+4],1 ; hd read - mark as same as in hd
yeshdcache:
mov esi,edi
shl esi,9
add esi,0x600000+65536
mov edi,ebx
mov ecx,512/4
cld
rep movsd ; move data
; blok_read_2:
pop edi esi ecx
ret
hd_write:
;-----------------------------------------------------------
; input : eax = block
; ebx = pointer to memory
;-----------------------------------------------------------
push ecx esi edi
; check if the cache already has the sector and overwrite it
mov ecx,cache_max
mov esi,0x600000+8
mov edi,1
hdwritecache:
cmp dword [esi+4],0 ; if cache slot is empty
je not_in_cache_write
cmp [esi],eax ; if the slot has the sector
je yes_in_cache_write
not_in_cache_write:
add esi,8
inc edi
dec ecx
jnz hdwritecache
; sector not found in cache
; write the block to a new location
call find_empty_slot ; ret in edi
lea esi,[edi*8+0x600000]
mov [esi],eax ; sector number
yes_in_cache_write:
mov dword [esi+4],2 ; write - differs from hd
shl edi,9
add edi,0x600000+65536
mov esi,ebx
mov ecx,512/4
cld
rep movsd ; move data
pop edi esi ecx
ret
write_cache:
;-----------------------------------------------------------
; write all changed sectors to disk
;-----------------------------------------------------------
push eax ecx edx esi edi
; write difference ( 2 ) from cache to hd
mov ecx,cache_max
mov esi,0x600000+8
mov edi,1
write_cache_more:
cmp dword [esi+4],2 ; if cache slot is not different
jne does_not_need_writing
mov dword [esi+4],1 ; same as in hd
mov eax,[esi] ; eax = sector to write
cmp eax,[PARTITION_START]
jb danger
cmp eax,[PARTITION_END]
ja danger
call wait_for_hd_idle
cli
xor eax,eax
mov edx,[hdbase]
inc edx
out dx,al
inc edx
inc eax
out dx,al
inc edx
mov eax,[esi] ; eax = sector to write
out dx,al
shr eax,8
inc edx
out dx,al
shr eax,8
inc edx
out dx,al
shr eax,8
inc edx
and al,1+2+4+8
add al,byte [hdid]
add al,128+64+32
out dx,al
inc edx
mov al,30h
out dx,al
sti
call wait_for_sector_buffer
cmp [hd_error],0
jne hd_write_error
push ecx esi
cli
mov esi,edi
shl esi,9
add esi,0x600000+65536 ; esi = from memory position
mov ecx,256
mov edx,[hdbase]
cld
rep outsw
sti
pop esi ecx
danger:
does_not_need_writing:
add esi,8
inc edi
dec ecx
jnz write_cache_more
pop edi esi edx ecx eax
ret
find_empty_slot:
;-----------------------------------------------------------
; find empty or read slot, flush cache if next 10% is used by write
; output : edi = cache slot
;-----------------------------------------------------------
push ecx esi
search_again:
mov ecx,cache_max*10/100
mov edi,[cache_search_start]
search_for_empty:
inc edi
cmp edi,cache_max
jbe inside_cache
mov edi,1
inside_cache:
cmp dword [edi*8+0x600000+4],2 ; get cache slot info
jb found_slot ; it's empty or read
dec ecx
jnz search_for_empty
call write_cache ; no empty slots found, write all
jmp search_again ; and start again
found_slot:
mov [cache_search_start],edi
pop esi ecx
ret
save_hd_wait_timeout:
push eax
mov eax,[timer_ticks];[0xfdf0]
add eax,300 ; 3 sec timeout
mov [hd_wait_timeout],eax
pop eax
ret
check_hd_wait_timeout:
push eax
mov eax,[hd_wait_timeout]
cmp [timer_ticks], eax ;[0xfdf0],eax
jg hd_timeout_error
pop eax
ret
iglobal
hd_timeout_str db 'K : FS - HD timeout',13,10,0
hd_read_str db 'K : FS - HD read error',13,10,0
hd_write_str db 'K : FS - HD write error',13,10,0
endg
hd_timeout_error:
call clear_hd_cache
call clear_application_table_status
mov esi,hd_timeout_str
call sys_msg_board_str
jmp $
hd_read_error:
call clear_hd_cache
call clear_application_table_status
mov esi,hd_read_str
call sys_msg_board_str
jmp $
hd_write_error:
call clear_hd_cache
call clear_application_table_status
mov esi,hd_write_str
call sys_msg_board_str
jmp $
wait_for_hd_idle:
push eax edx
call save_hd_wait_timeout
mov edx,[hdbase]
add edx,0x7
wfhil1:
call check_hd_wait_timeout
in al,dx
test al,128
jnz wfhil1
pop edx eax
ret
wait_for_sector_buffer:
push eax edx
mov edx,[hdbase]
add edx,0x7
call save_hd_wait_timeout
hdwait_sbuf: ; wait for sector buffer to be ready
call check_hd_wait_timeout
in al,dx
test al,8
jz hdwait_sbuf
mov [hd_error],0
cmp [hd_setup],1 ; do not mark error for setup request
je buf_wait_ok
test al,1 ; previous command ended up with an error
jz buf_wait_ok
mov [hd_error],1
buf_wait_ok:
pop edx eax
ret
read_hd_file:
;-----------------------------------------------------------------
;
; Converting old reading function for hd-application start.
;
; IN:
;
; eax - pointer to file (0 = read only first sector of drive: eg 'label')
; ebx - file lenght
; ecx - start 512 byte block number
; edx - number of blocks to read
; esi - pointer to return/work area (atleast 20 000 bytes)
;
; For new read function
;
; EAX (PAR0) pointer to file-name
; ECX (PAR1) pointer to buffer
; EBX (PAR2) vt file blocks to read
; EDX (PAR3) pointer to path
; ESI vt first 512 block to read
; EDI if 0 - return root
;--------------------------------------------------------------------------
push ecx esi edi
mov esi,eax
mov edi,startpath
mov ecx,250
cld
rep movsb
pop edi esi ecx
mov eax,startpath
mov [eax+ebx-12],byte 0
push eax ebx ecx edx esi
pop ecx ; pointer to buffer
add ecx,1024
pop ebx ; number of blocks to read
pop esi ; first block to read
dec esi
pop eax ; file length
pop edx ; pointer to path
mov edi,12
lea eax,[eax+edx-12+1]
call file_read
ret