;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2004-2013. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; FAT32.INC ;;
;; ;;
;; FAT16/32 functions for KolibriOS ;;
;; ;;
;; Copyright 2002 Paolo Minazzi, paolo.minazzi@inwind.it ;;
;; ;;
;; See file COPYING for details ;;
;; 04.02.2007 LFN create folder - diamond ;;
;; 08.10.2006 LFN delete file/folder - diamond ;;
;; 20.08.2006 LFN set file size (truncate/extend) - diamond ;;
;; 17.08.2006 LFN write/append to file - diamond ;;
;; 23.06.2006 LFN start application - diamond ;;
;; 15.06.2006 LFN get/set file/folder info - diamond ;;
;; 27.05.2006 LFN create/rewrite file - diamond ;;
;; 04.05.2006 LFN read folder - diamond ;;
;; 29.04.2006 Elimination of hangup after the ;;
;; expiration hd_wait_timeout - Mario79 ;;
;; 23.04.2006 LFN read file - diamond ;;
;; 28.01.2006 find all Fat16/32 partition in all input point ;;
;; to MBR, see file part_set.inc - Mario79 ;;
;; 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 ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
$Revision: 3908 $
cache_max equ 1919 ; max. is 1919*512+0x610000=0x6ffe00
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]
; Internal data for every FAT partition.
struct FAT PARTITION
fs_type db ?
fat16_root db 0 ; flag for fat16 rootdir
fat_change db 0 ; 1=fat has changed
db ? ; alignment
Lock MUTEX ? ; currently operations with one partition
; can not be executed in parallel since the
; legacy code is not ready; this mutex guards
; all operations
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
fatStartScan dd 2
cluster_tmp dd 0 ; used by analyze_directory
; and analyze_directory_to_write
longname_sec1 dd 0 ; used by analyze_directory to save 2 previous
longname_sec2 dd 0 ; directory sectors for delete long filename
fat_in_cache dd -1
fat_cache rb 512
buffer rb 512
fsinfo_buffer rb 512
ends
uglobal
align 4
partition_count dd 0 ; partitions found by set_FAT32_variables
hd_error dd 0 ; set by wait_for_sector_buffer
hd_setup dd 0
hd_wait_timeout dd 0
cache_search_start dd 0 ; used by find_empty_slot
endg
uglobal
align 4
Sector512: ; label for dev_hdcd.inc
buffer:
times 512 db 0
endg
iglobal
align 4
fat_user_functions:
dd free
dd (fat_user_functions_end - fat_user_functions - 4) / 4
dd fat_Read
dd fat_ReadFolder
dd fat_Rewrite
dd fat_Write
dd fat_SetFileEnd
dd fat_GetFileInfo
dd fat_SetFileInfo
dd 0
dd fat_Delete
dd fat_CreateFolder
fat_user_functions_end:
endg
; these labels are located before the main function to make
; most of jumps to these be short
fat_create_partition.free_return0:
mov eax, ebp
call free
pop ebp
fat_create_partition.return0:
xor eax, eax
ret
fat_create_partition:
; bootsector must have been successfully read
cmp dword [esp+4], 0
jnz .return0
; bootsector signature must be correct
cmp word [ebx+0x1fe], 0xaa55
jnz .return0
; sectors per cluster must be nonzero
cmp byte [ebx+0xd], 0
jz .return0
; bytes per sector must be 0x200
cmp word [ebx+0xb], 0x200
jnz .return0
; number of fats must be nonzero
cmp byte [ebx+0x10], 0
jz .return0
; The only reason to be invalid partition now is FAT12. Since the test for
; FAT size requires knowledge of some calculated values, which are also used
; in the normal operation, let's hope for the best and allocate data now; if
; it will prove wrong, just deallocate it.
movi eax, sizeof.FAT
call malloc
test eax, eax
jz .return0
mov ecx, dword [ebp+PARTITION.FirstSector]
mov dword [eax+FAT.FirstSector], ecx
mov ecx, dword [ebp+PARTITION.FirstSector+4]
mov dword [eax+FAT.FirstSector+4], ecx
mov ecx, dword [ebp+PARTITION.Length]
mov dword [eax+FAT.Length], ecx
mov ecx, dword [ebp+PARTITION.Length+4]
mov dword [eax+FAT.Length+4], ecx
mov ecx, [ebp+PARTITION.Disk]
mov [eax+FAT.Disk], ecx
mov [eax+FAT.FSUserFunctions], fat_user_functions
or [eax+FAT.fat_in_cache], -1
mov [eax+FAT.fat_change], 0
push ebp
mov ebp, eax
lea ecx, [ebp+FAT.Lock]
call mutex_init
movzx eax, word [ebx+0xe] ; sectors reserved
mov [ebp+FAT.FAT_START], eax
movzx eax, byte [ebx+0xd] ; sectors per cluster
mov [ebp+FAT.SECTORS_PER_CLUSTER], eax
movzx ecx, word [ebx+0xb] ; bytes per sector
mov [ebp+FAT.BYTES_PER_SECTOR], ecx
movzx eax, word [ebx+0x11] ; count of rootdir entries (=0 fat32)
shl eax, 5 ; mul 32
dec ecx
add eax, ecx ; round up if not equal count
inc ecx ; bytes per sector
xor edx, edx
div ecx
mov [ebp+FAT.ROOT_SECTORS], eax ; count of rootdir sectors
movzx eax, word [ebx+0x16] ; sectors per fat <65536
test eax, eax
jnz @f
mov eax, [ebx+0x24] ; sectors per fat
@@:
mov [ebp+FAT.SECTORS_PER_FAT], eax
movzx eax, byte [ebx+0x10] ; number of fats
mov [ebp+FAT.NUMBER_OF_FATS], eax
imul eax, [ebp+FAT.SECTORS_PER_FAT]
add eax, [ebp+FAT.FAT_START]
mov [ebp+FAT.ROOT_START], eax ; rootdir = fat_start + fat_size * fat_count
add eax, [ebp+FAT.ROOT_SECTORS] ; rootdir sectors should be 0 on fat32
mov [ebp+FAT.DATA_START], eax ; data area = rootdir + rootdir_size
movzx eax, word [ebx+0x13] ; total sector count <65536
test eax, eax
jnz @f
mov eax, [ebx+0x20] ; total sector count
@@:
mov dword [ebp+FAT.Length], eax
and dword [ebp+FAT.Length+4], 0
sub eax, [ebp+FAT.DATA_START] ; eax = count of data sectors
xor edx, edx
div [ebp+FAT.SECTORS_PER_CLUSTER]
inc eax
mov [ebp+FAT.LAST_CLUSTER], eax
dec eax ; cluster count
mov [ebp+FAT.fatStartScan], 2
; limits by Microsoft Hardware White Paper v1.03
cmp eax, 4085 ; 0xff5
jb .free_return0 ; fat12 not supported
cmp eax, 65525 ; 0xfff5
jb .fat16
.fat32:
mov eax, [ebx+0x2c] ; rootdir cluster
mov [ebp+FAT.ROOT_CLUSTER], eax
movzx eax, word [ebx+0x30]
mov [ebp+FAT.ADR_FSINFO], eax
push ebx
add ebx, 512
call fs_read32_sys
test eax, eax
jnz @f
mov eax, [ebx+0x1ec]
cmp eax, -1
jz @f
mov [ebp+FAT.fatStartScan], eax
@@:
pop ebx
mov [ebp+FAT.fatRESERVED], 0x0FFFFFF6
mov [ebp+FAT.fatBAD], 0x0FFFFFF7
mov [ebp+FAT.fatEND], 0x0FFFFFF8
mov [ebp+FAT.fatMASK], 0x0FFFFFFF
mov al, 32
mov [ebp+FAT.fs_type], al
mov eax, ebp
pop ebp
ret
.fat16:
and [ebp+FAT.ROOT_CLUSTER], 0
mov [ebp+FAT.fatRESERVED], 0x0000FFF6
mov [ebp+FAT.fatBAD], 0x0000FFF7
mov [ebp+FAT.fatEND], 0x0000FFF8
mov [ebp+FAT.fatMASK], 0x0000FFFF
mov al, 16
mov [ebp+FAT.fs_type], al
mov eax, ebp
pop ebp
ret
set_FAT:
;--------------------------------
; input : EAX = cluster
; EDX = value to save
; EBP = pointer to FAT structure
; output : EDX = old value
;--------------------------------
; out: CF set <=> error
push eax ebx esi
cmp eax, 2
jb sfc_error
cmp eax, [ebp+FAT.LAST_CLUSTER]
ja sfc_error
cmp [ebp+FAT.fs_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, [ebp+FAT.FAT_START]
lea ebx, [ebp+FAT.fat_cache]
cmp eax, [ebp+FAT.fat_in_cache]; is fat sector already in memory?
je sfc_in_cache ; yes
cmp [ebp+FAT.fat_change], 0; is fat changed?
je sfc_no_change ; no
call write_fat_sector; yes. write it into disk
jc sfc_error
sfc_no_change:
mov [ebp+FAT.fat_in_cache], eax; save fat sector
call fs_read32_sys
test eax, eax
jne sfc_error
sfc_in_cache:
cmp [ebp+FAT.fs_type], 16
jne sfc_test32
sfc_set16:
xchg [ebx+esi], dx ; save new value and get old value
jmp sfc_write
sfc_test32:
mov eax, [ebp+FAT.fatMASK]
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 [ebp+FAT.fat_change], 1; fat has changed
sfc_nonzero:
and edx, [ebp+FAT.fatMASK]
sfc_return:
pop esi ebx eax
ret
sfc_error:
stc
jmp sfc_return
get_FAT:
;--------------------------------
; input : EAX = cluster
; EBP = pointer to FAT structure
; output : EAX = next cluster
;--------------------------------
; out: CF set <=> error
push ebx esi
cmp [ebp+FAT.fs_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, [ebp+FAT.FAT_START]
lea ebx, [ebp+FAT.fat_cache]
cmp eax, [ebp+FAT.fat_in_cache]; is fat sector already in memory?
je gfc_in_cache
cmp [ebp+FAT.fat_change], 0; is fat changed?
je gfc_no_change ; no
call write_fat_sector; yes. write it into disk
jc hd_error_01
gfc_no_change:
mov [ebp+FAT.fat_in_cache], eax
call fs_read32_sys
test eax, eax
jne hd_error_01
gfc_in_cache:
mov eax, [ebx+esi]
and eax, [ebp+FAT.fatMASK]
gfc_return:
pop esi ebx
ret
hd_error_01:
stc
jmp gfc_return
get_free_FAT:
;-----------------------------------------------------------
; 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, [ebp+FAT.LAST_CLUSTER]; counter for full disk
sub ecx, 2
mov eax, [ebp+FAT.fatStartScan]
cmp eax, 2
jb gff_reset
gff_test:
cmp eax, [ebp+FAT.LAST_CLUSTER]; if above last cluster start at cluster 2
jbe gff_in_range
gff_reset:
mov eax, 2
gff_in_range:
push eax
call get_FAT ; get cluster state
jc gff_not_found_1
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_not_found_1:
pop eax
jmp gff_not_found
gff_found:
lea ecx, [eax+1]
mov [ebp+FAT.fatStartScan], ecx
pop ecx
clc
ret
write_fat_sector:
;-----------------------------------------------------------
; write changed fat to disk
;-----------------------------------------------------------
push eax ebx ecx
mov [ebp+FAT.fat_change], 0
mov eax, [ebp+FAT.fat_in_cache]
cmp eax, -1
jz write_fat_not_used
lea ebx, [ebp+FAT.fat_cache]
mov ecx, [ebp+FAT.NUMBER_OF_FATS]
write_next_fat:
push eax
call fs_write32_sys
test eax, eax
pop eax
jnz write_fat_not_used
add eax, [ebp+FAT.SECTORS_PER_FAT]
dec ecx
jnz write_next_fat
write_fat_not_used:
pop ecx ebx eax
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
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 [ebp+FAT.fs_type], 32 ; free disk space only used by fat32
jne add_dfs_no
push eax ebx
mov eax, [ebp+FAT.ADR_FSINFO]
lea ebx, [ebp+FAT.fsinfo_buffer]
call fs_read32_sys
test eax, eax
jnz add_not_fs
cmp dword [ebx+0x1fc], 0xaa550000; check sector id
jne add_not_fs
add [ebx+0x1e8], ecx
push [ebp+FAT.fatStartScan]
pop dword [ebx+0x1ec]
mov eax, [ebp+FAT.ADR_FSINFO]
call fs_write32_sys
; jc add_not_fs
add_not_fs:
pop ebx eax
add_dfs_no:
ret
clear_cluster_chain:
;-----------------------------------------------------
; input : eax = first cluster
;-----------------------------------------------------
push eax ecx edx
xor ecx, ecx ; cluster count
clean_new_chain:
cmp eax, [ebp+FAT.LAST_CLUSTER]; end of file
ja delete_OK
cmp eax, 2 ; unfinished fat chain or zero length file
jb delete_OK
cmp eax, [ebp+FAT.ROOT_CLUSTER]; don't remove root cluster
jz delete_OK
xor edx, edx
call set_FAT ; clear fat entry
jc access_denied_01
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
clc
access_denied_01:
pop edx ecx eax
ret
if 0
get_hd_info:
;-----------------------------------------------------------
; output : eax = 0 - ok
; 3 - unknown FS
; 10 - access denied
; edx = cluster size in bytes
; ebx = total clusters on disk
; ecx = free clusters on disk
;-----------------------------------------------------------
cmp [ebp+FAT.fs_type], 16
jz info_fat_ok
cmp [ebp+FAT.fs_type], 32
jz 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, [ebp+FAT.LAST_CLUSTER]
info_cluster:
push eax
call get_FAT ; get cluster info
jc info_access_denied
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, [ebp+FAT.SECTORS_PER_CLUSTER], 512; cluster size in bytes
xor eax, eax
ret
info_access_denied:
add esp, 4
xor edx, edx
xor ebx, ebx
xor ecx, ecx
mov eax, ERROR_ACCESS_DENIED
ret
end if
update_disk:
;-----------------------------------------------------------
; write changed fat and cache to disk
;-----------------------------------------------------------
cmp [ebp+FAT.fat_change], 0 ; is fat changed?
je upd_no_change
call write_fat_sector
jc update_disk_acces_denied
upd_no_change:
push esi
mov esi, [ebp+PARTITION.Disk]
call disk_sync
pop esi
update_disk_acces_denied:
ret
fat_lock:
lea ecx, [ebp+FAT.Lock]
jmp mutex_lock
fat_unlock:
lea ecx, [ebp+FAT.Lock]
jmp mutex_unlock
; \begin{diamond}
hd_find_lfn:
; in: ebp -> FAT structure
; in: esi+[esp+4] -> name
; out: CF=1 - file not found, eax=error code
; else CF=0 and edi->direntry, eax=sector
; destroys eax
push esi edi
push 0
push 0
push fat16_root_first
push fat16_root_next
mov eax, [ebp+FAT.ROOT_CLUSTER]
cmp [ebp+FAT.fs_type], 32
jz .fat32
.loop:
call fat_find_lfn
jc .notfound
cmp byte [esi], 0
jz .found
.continue:
test byte [edi+11], 10h
jz .notfound
and dword [esp+12], 0
mov eax, [edi+20-2]
mov ax, [edi+26] ; cluster
.fat32:
mov [esp+8], eax
mov dword [esp+4], fat_notroot_first
mov dword [esp], fat_notroot_next
jmp .loop
.notfound:
add esp, 16
pop edi esi
stc
ret 4
.found:
lea eax, [esp+4+24]
cmp dword [eax], 0
jz @f
mov esi, [eax]
and dword [eax], 0
jmp .continue
@@:
lea eax, [esp+8]
cmp dword [eax], 0
jz .root
call fat_get_sector
jmp .cmn
.root:
mov eax, [eax+4]
add eax, [ebp+FAT.ROOT_START]
.cmn:
add esp, 20 ; CF=0
pop esi
ret 4
;----------------------------------------------------------------
; fat_Read - FAT16/32 implementation of reading a file
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_Read:
call fat_lock
push edi
cmp byte [esi], 0
jnz @f
.noaccess:
pop edi
.noaccess_2:
call fat_unlock
or ebx, -1
mov eax, ERROR_ACCESS_DENIED
ret
@@:
stdcall hd_find_lfn, [esp+4+4]
jnc .found
pop edi
push eax
call fat_unlock
pop eax
or ebx, -1
ret
.found:
test byte [edi+11], 0x10; do not allow read directories
jnz .noaccess
cmp dword [ebx+8], 0
jz @f
xor ebx, ebx
.reteof:
call fat_unlock
mov eax, ERROR_END_OF_FILE
pop edi
ret
@@:
mov ecx, [ebx+12] ; size
mov edx, [ebx+16] ; pointer
mov ebx, [ebx+4] ; file offset
push edx
push 0
mov eax, [edi+28]
sub eax, ebx
jb .eof
cmp eax, ecx
jae @f
mov ecx, eax
mov byte [esp], 6
@@:
mov eax, [edi+20-2]
mov ax, [edi+26]
; now eax=cluster, ebx=position, ecx=count, edx=buffer for data
.new_cluster:
jecxz .new_sector
cmp eax, 2
jb .eof
cmp eax, [ebp+FAT.fatRESERVED]
jae .eof
mov [ebp+FAT.cluster_tmp], eax
dec eax
dec eax
mov edi, [ebp+FAT.SECTORS_PER_CLUSTER]
imul eax, edi
add eax, [ebp+FAT.DATA_START]
.new_sector:
test ecx, ecx
jz .done
sub ebx, 512
jae .skip
add ebx, 512
jnz .force_buf
cmp ecx, 512
jb .force_buf
; we may read directly to given buffer
push eax ebx
mov ebx, edx
call fs_read32_app
test eax, eax
pop ebx eax
jne .noaccess_1
add edx, 512
sub ecx, 512
jmp .skip
.force_buf:
; we must read sector to temporary buffer and then copy it to destination
push eax ebx
lea ebx, [ebp+FAT.buffer]
call fs_read32_app
test eax, eax
mov eax, ebx
pop ebx
jne .noaccess_3
add eax, ebx
push ecx
add ecx, ebx
cmp ecx, 512
jbe @f
mov ecx, 512
@@:
sub ecx, ebx
mov ebx, edx
call memmove
add edx, ecx
sub [esp], ecx
pop ecx
pop eax
xor ebx, ebx
.skip:
inc eax
dec edi
jnz .new_sector
mov eax, [ebp+FAT.cluster_tmp]
call get_FAT
jc .noaccess_1
jmp .new_cluster
.noaccess_3:
pop eax
.noaccess_1:
pop eax
push ERROR_DEVICE
.done:
mov ebx, edx
call fat_unlock
pop eax edx edi
sub ebx, edx
ret
.eof:
mov ebx, edx
pop eax edx
sub ebx, edx
jmp .reteof
;----------------------------------------------------------------
; fat_ReadFolder - FAT16/32 implementation of reading a folder
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_ReadFolder:
call fat_lock
mov eax, [ebp+FAT.ROOT_CLUSTER]
push edi
cmp byte [esi], 0
jz .doit
stdcall hd_find_lfn, [esp+4+4]
jnc .found
pop edi
push eax
call fat_unlock
pop eax
or ebx, -1
ret
.found:
test byte [edi+11], 0x10 ; do not allow read files
jnz .found_dir
pop edi
call fat_unlock
or ebx, -1
mov eax, ERROR_ACCESS_DENIED
ret
.found_dir:
mov eax, [edi+20-2]
mov ax, [edi+26] ; eax=cluster
.doit:
push esi
sub esp, 262*2 ; reserve space for LFN
push dword [ebx+8] ; for fat_get_name: read ANSI/UNICODE name
mov edx, [ebx+16] ; pointer to buffer
; init header
push eax
mov edi, edx
mov ecx, 32/4
xor eax, eax
rep stosd
pop eax
mov byte [edx], 1 ; version
mov esi, edi ; esi points to BDFE
mov ecx, [ebx+12] ; number of blocks to read
mov ebx, [ebx+4] ; index of the first block
.new_cluster:
mov [ebp+FAT.cluster_tmp], eax
test eax, eax
jnz @f
cmp [ebp+FAT.fs_type], 32
jz .notfound
mov eax, [ebp+FAT.ROOT_START]
push [ebp+FAT.ROOT_SECTORS]
push ebx
jmp .new_sector
@@:
dec eax
dec eax
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
push [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
push ebx
.new_sector:
lea ebx, [ebp+FAT.buffer]
mov edi, ebx
push eax
call fs_read32_sys
test eax, eax
pop eax
jnz .notfound2
add ebx, 512
push eax
.l1:
push ebp
lea ebp, [esp+20]
call fat_get_name
pop ebp
jc .l2
cmp byte [edi+11], 0xF
jnz .do_bdfe
add edi, 0x20
cmp edi, ebx
jb .do_bdfe
pop eax
inc eax
dec dword [esp+4]
jnz @f
mov eax, [ebp+FAT.cluster_tmp]
test eax, eax
jz .done
call get_FAT
jc .notfound2
cmp eax, 2
jb .done
cmp eax, [ebp+FAT.fatRESERVED]
jae .done
push eax
mov eax, [ebp+FAT.SECTORS_PER_CLUSTER]
mov [esp+8], eax
pop eax
mov [ebp+FAT.cluster_tmp], eax
dec eax
dec eax
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
@@:
lea ebx, [ebp+FAT.buffer]
mov edi, ebx
push eax
call fs_read32_sys
test eax, eax
pop eax
jnz .notfound2
add ebx, 512
push eax
.do_bdfe:
inc dword [edx+8] ; new file found
dec dword [esp+4]
jns .l2
dec ecx
js .l2
inc dword [edx+4] ; new file block copied
push ebp
lea ebp, [esp+20]
call fat_entry_to_bdfe
pop ebp
.l2:
add edi, 0x20
cmp edi, ebx
jb .l1
pop eax
inc eax
dec dword [esp+4]
jnz .new_sector
mov eax, [ebp+FAT.cluster_tmp]
test eax, eax
jz .done
call get_FAT
jc .notfound2
cmp eax, 2
jb .done
cmp eax, [ebp+FAT.fatRESERVED]
jae .done
push eax
mov eax, [ebp+FAT.SECTORS_PER_CLUSTER]
mov [esp+8], eax
pop eax
pop ebx
add esp, 4
jmp .new_cluster
.notfound2:
add esp, 8
.notfound:
add esp, 262*2+4
pop esi edi
mov ebx, [edx+4]
call fat_unlock
mov eax, ERROR_DEVICE
ret
.done:
add esp, 262*2+4+8
mov ebx, [edx+4]
xor eax, eax
dec ecx
js @f
mov al, ERROR_END_OF_FILE
@@:
push eax
call fat_unlock
pop eax
pop esi edi
ret
fat16_root_next:
push ecx
lea ecx, [ebp+FAT.buffer+0x200-0x20]
cmp edi, ecx
jae fat16_root_next_sector
pop ecx
add edi, 0x20
ret ; CF=0
fat16_root_next_sector:
; read next sector
push [ebp+FAT.longname_sec2]
pop [ebp+FAT.longname_sec1]
mov ecx, [eax+4]
push ecx
add ecx, [ebp+FAT.ROOT_START]
mov [ebp+FAT.longname_sec2], ecx
pop ecx
inc ecx
mov [eax+4], ecx
cmp ecx, [ebp+FAT.ROOT_SECTORS]
pop ecx
jb fat16_root_first
mov eax, ERROR_FILE_NOT_FOUND
stc
ret
fat16_root_first:
mov eax, [eax+4]
add eax, [ebp+FAT.ROOT_START]
push ebx
lea edi, [ebp+FAT.buffer]
mov ebx, edi
call fs_read32_sys
pop ebx
test eax, eax
jnz .readerr
ret ; CF=0
.readerr:
mov eax, ERROR_DEVICE
stc
ret
.notfound:
mov eax, ERROR_FILE_NOT_FOUND
stc
ret
fat16_root_begin_write:
push edi eax
call fat16_root_first
pop eax edi
ret
fat16_root_end_write:
pusha
mov eax, [eax+4]
add eax, [ebp+FAT.ROOT_START]
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
popa
ret
fat16_root_next_write:
push ecx
lea ecx, [ebp+FAT.buffer+0x200]
cmp edi, ecx
jae @f
pop ecx
ret
@@:
call fat16_root_end_write
jmp fat16_root_next_sector
fat16_root_extend_dir:
stc
ret
fat_notroot_next:
push ecx
lea ecx, [ebp+FAT.buffer+0x200-0x20]
cmp edi, ecx
jae fat_notroot_next_sector
pop ecx
add edi, 0x20
ret ; CF=0
fat_notroot_next_sector:
push [ebp+FAT.longname_sec2]
pop [ebp+FAT.longname_sec1]
push eax
call fat_get_sector
mov [ebp+FAT.longname_sec2], eax
pop eax
mov ecx, [eax+4]
inc ecx
cmp ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
jae fat_notroot_next_cluster
mov [eax+4], ecx
jmp @f
fat_notroot_next_cluster:
push eax
mov eax, [eax]
call get_FAT
mov ecx, eax
pop eax
jc fat_notroot_first.deverr
cmp ecx, 2
jb fat_notroot_next_err
cmp ecx, [ebp+FAT.fatRESERVED]
jae fat_notroot_next_err
mov [eax], ecx
and dword [eax+4], 0
@@:
pop ecx
fat_notroot_first:
call fat_get_sector
push ebx
lea edi, [ebp+FAT.buffer]
mov ebx, edi
call fs_read32_sys
pop ebx
test eax, eax
jz .ret ; CF=0
push ecx
.deverr:
pop ecx
mov eax, ERROR_DEVICE
stc
.ret:
ret
fat_notroot_next_err:
pop ecx
mov eax, ERROR_FILE_NOT_FOUND
stc
ret
fat_notroot_begin_write:
push eax edi
call fat_notroot_first
pop edi eax
ret
fat_notroot_end_write:
call fat_get_sector
push ebx
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
pop ebx
ret
fat_notroot_next_write:
push ecx
lea ecx, [ebp+FAT.buffer+0x200]
cmp edi, ecx
jae @f
pop ecx
ret
@@:
push eax
call fat_notroot_end_write
pop eax
jmp fat_notroot_next_sector
fat_notroot_extend_dir:
push eax
call get_free_FAT
jnc .found
pop eax
ret ; CF=1
.found:
push edx
mov edx, [ebp+FAT.fatEND]
call set_FAT
jc .writeerr
mov edx, eax
mov eax, [esp+4]
mov eax, [eax]
push edx
call set_FAT
pop edx
jnc @f
.writeerr:
pop edx
pop eax
stc
ret
@@:
push ecx
or ecx, -1
call add_disk_free_space
; zero new cluster
mov ecx, 512/4
lea edi, [ebp+FAT.buffer]
push edi
xor eax, eax
rep stosd
pop edi
pop ecx
mov eax, [esp+4]
mov [eax], edx
and dword [eax+4], 0
pop edx
mov eax, [eax]
dec eax
dec eax
push ebx ecx
mov ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
imul eax, ecx
add eax, [ebp+FAT.DATA_START]
mov ebx, edi
@@:
push eax
call fs_write32_sys
pop eax
inc eax
loop @b
pop ecx ebx eax
clc
ret
fat_get_sector:
push ecx
mov ecx, [eax]
dec ecx
dec ecx
imul ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
add ecx, [ebp+FAT.DATA_START]
add ecx, [eax+4]
mov eax, ecx
pop ecx
ret
fshrad:
call fat_unlock
mov eax, ERROR_ACCESS_DENIED
xor ebx, ebx
ret
;----------------------------------------------------------------
; fat_CreateFolder - FAT16/32 implementation of creating a folder
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_CreateFolder:
push 1
jmp fat_Rewrite.common
;----------------------------------------------------------------
; fat_Rewrite - FAT16/32 implementation of creating a new file
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_Rewrite:
push 0
.common:
call fat_lock
pop eax
cmp byte [esi], 0
jz fshrad
mov ecx, [ebx+12]
mov edx, [ebx+16]
pushad
xor edi, edi
mov edx, [esp+4+20h]
push esi
test edx, edx
jz @f
mov esi, edx
@@:
lodsb
test al, al
jz @f
cmp al, '/'
jnz @b
lea edi, [esi-1]
jmp @b
@@:
pop esi
test edi, edi
jnz .noroot
test edx, edx
jnz .hasebp
mov edx, [ebp+FAT.ROOT_CLUSTER]
cmp [ebp+FAT.fs_type], 32
jz .pushnotroot
xor edx, edx
push edx
push fat16_root_extend_dir
push fat16_root_end_write
push fat16_root_next_write
push fat16_root_begin_write
push edx
push edx
push fat16_root_first
push fat16_root_next
jmp .common1
.hasebp:
mov eax, ERROR_ACCESS_DENIED
cmp byte [edx], 0
jz .ret1
stdcall hd_find_lfn, 0
mov esi, [esp+4+20h]
jc .ret1
jmp .common0
.noroot:
mov eax, ERROR_ACCESS_DENIED
cmp byte [edi+1], 0
jz .ret1
; check existence
mov byte [edi], 0
push edi
stdcall hd_find_lfn, [esp+4+24h]
pop esi
mov byte [esi], '/'
jnc @f
.notfound0:
mov eax, ERROR_FILE_NOT_FOUND
.ret1:
mov [esp+28], eax
call fat_unlock
popad
xor ebx, ebx
ret
@@:
inc esi
.common0:
test byte [edi+11], 0x10 ; must be directory
mov eax, ERROR_ACCESS_DENIED
jz .ret1
mov edx, [edi+20-2]
mov dx, [edi+26] ; ebp=cluster
mov eax, ERROR_FAT_TABLE
cmp edx, 2
jb .ret1
.pushnotroot:
push edx
push fat_notroot_extend_dir
push fat_notroot_end_write
push fat_notroot_next_write
push fat_notroot_begin_write
push 0
push edx
push fat_notroot_first
push fat_notroot_next
.common1:
call fat_find_lfn
jc .notfound
; found
test byte [edi+11], 10h
jz .exists_file
; found directory; if we are creating directory, return OK,
; if we are creating file, say "access denied"
add esp, 36
call fat_unlock
popad
test al, al
mov eax, ERROR_ACCESS_DENIED
jz @f
mov al, 0
@@:
xor ebx, ebx
ret
.exists_file:
; found file; if we are creating directory, return "access denied",
; if we are creating file, delete existing file and continue
cmp byte [esp+36+28], 0
jz @f
add esp, 36
call fat_unlock
popad
mov eax, ERROR_ACCESS_DENIED
xor ebx, ebx
ret
@@:
; delete FAT chain
push edi
xor eax, eax
mov dword [edi+28], eax ; zero size
xor ecx, ecx
mov eax, [edi+20-2]
mov ax, [edi+26]
mov word [edi+20], cx
mov word [edi+26], cx
test eax, eax
jz .done1
@@:
cmp eax, [ebp+FAT.fatRESERVED]
jae .done1
push edx
xor edx, edx
call set_FAT
mov eax, edx
pop edx
jc .done1
inc ecx
jmp @b
.done1:
pop edi
call get_time_for_file
mov [edi+22], ax
call get_date_for_file
mov [edi+24], ax
mov [edi+18], ax
or byte [edi+11], 20h ; set 'archive' attribute
jmp .doit
.notfound:
; file is not found; generate short name
call fat_name_is_legal
jc @f
add esp, 36
call fat_unlock
popad
mov eax, ERROR_FILE_NOT_FOUND
xor ebx, ebx
ret
@@:
sub esp, 12
mov edi, esp
call fat_gen_short_name
.test_short_name_loop:
push esi edi ecx
mov esi, edi
lea eax, [esp+12+12+8]
mov edx, [eax+24]
mov [eax], edx
and dword [eax+4], 0
call dword [eax-4]
jc .found
.test_short_name_entry:
cmp byte [edi+11], 0xF
jz .test_short_name_cont
mov ecx, 11
push esi edi
repz cmpsb
pop edi esi
jz .short_name_found
.test_short_name_cont:
lea eax, [esp+12+12+8]
call dword [eax-8]
jnc .test_short_name_entry
jmp .found
.short_name_found:
pop ecx edi esi
call fat_next_short_name
jnc .test_short_name_loop
.disk_full:
add esp, 12+36
call fat_unlock
popa
mov eax, ERROR_DISK_FULL
xor ebx, ebx
ret
.found:
pop ecx edi esi
; now find space in directory
; we need to save LFN <=> LFN is not equal to short name <=> generated name contains '~'
mov al, '~'
push ecx edi
mov ecx, 8
repnz scasb
movi eax, 1 ; 1 entry
jnz .notilde
; we need ceil(strlen(esi)/13) additional entries = floor((strlen(esi)+12+13)/13) total
xor eax, eax
@@:
cmp byte [esi], 0
jz @f
inc esi
inc eax
jmp @b
@@:
sub esi, eax
add eax, 12+13
mov ecx, 13
push edx
cdq
div ecx
pop edx
.notilde:
push -1
push -1
push -1
; find <eax> successive entries in directory
xor ecx, ecx
push eax
lea eax, [esp+16+8+12+8]
mov edx, [eax+24]
mov [eax], edx
and dword [eax+4], 0
call dword [eax-4]
pop eax
jnc .scan_dir
.fsfrfe3:
add esp, 12+8+12+36
call fat_unlock
popad
mov eax, ERROR_DEVICE
xor ebx, ebx
ret
.scan_dir:
cmp byte [edi], 0
jz .free
cmp byte [edi], 0xE5
jz .free
xor ecx, ecx
.scan_cont:
push eax
lea eax, [esp+16+8+12+8]
call dword [eax-8]
mov edx, eax
pop eax
jnc .scan_dir
cmp edx, ERROR_DEVICE
jz .fsfrfe3
push eax
lea eax, [esp+16+8+12+8]
call dword [eax+20] ; extend directory
pop eax
jnc .scan_dir
add esp, 12+8+12+36
call fat_unlock
popad
mov eax, ERROR_DISK_FULL
xor ebx, ebx
ret
.free:
test ecx, ecx
jnz @f
mov [esp], edi
mov ecx, [esp+12+8+12+8]
mov [esp+4], ecx
mov ecx, [esp+12+8+12+12]
mov [esp+8], ecx
xor ecx, ecx
@@:
inc ecx
cmp ecx, eax
jb .scan_cont
; found!
push esi ecx
; If creating a directory, allocate one data cluster now and fail immediately
; if this is impossible. This prevents from creating an invalid directory entry
; on a full disk.
; yup, the argument is quite non-intuitive... but what should I do if
; the entire function uses such arguments? BTW, it refers to al from pushad,
; which in turn is filled with 0 in fat_Rewrite and 1 in fat_CreateFolder.
cmp byte [esp+8+12+8+12+36+28], 0
jz .no.preallocate.folder.data
call get_free_FAT
jnc @f
add esp, 8+12+8
jmp .disk_full
@@:
mov [esp+8+12+8+12+36+20], eax ; store the cluster somewhere
.no.preallocate.folder.data:
; calculate name checksum
mov esi, [esp+8+12]
mov ecx, 11
xor eax, eax
@@:
ror al, 1
add al, [esi]
inc esi
loop @b
pop ecx esi
pop edi
pop dword [esp+8+12+12]
pop dword [esp+8+12+12]
; edi points to first entry in free chunk
dec ecx
jz .nolfn
push esi
push eax
lea eax, [esp+8+8+12+8]
call dword [eax+8] ; begin write
mov al, 40h
.writelfn:
or al, cl
mov esi, [esp+4]
push ecx
dec ecx
imul ecx, 13
add esi, ecx
stosb
mov cl, 5
call fs_RamdiskRewrite.read_symbols
mov ax, 0xF
stosw
mov al, [esp+4]
stosb
mov cl, 6
call fs_RamdiskRewrite.read_symbols
xor eax, eax
stosw
mov cl, 2
call fs_RamdiskRewrite.read_symbols
pop ecx
lea eax, [esp+8+8+12+8]
call dword [eax+12] ; next write
xor eax, eax
loop .writelfn
pop eax
pop esi
; lea eax, [esp+8+12+8]
; call dword [eax+16] ; end write
.nolfn:
xchg esi, [esp]
mov ecx, 11
rep movsb
mov word [edi], 20h ; attributes
sub edi, 11
pop esi ecx
add esp, 12
mov byte [edi+13], 0 ; tenths of a second at file creation time
call get_time_for_file
mov [edi+14], ax ; creation time
mov [edi+22], ax ; last write time
call get_date_for_file
mov [edi+16], ax ; creation date
mov [edi+24], ax ; last write date
mov [edi+18], ax ; last access date
xor ecx, ecx
mov word [edi+20], cx ; high word of cluster
mov word [edi+26], cx ; low word of cluster - to be filled
mov dword [edi+28], ecx ; file size - to be filled
cmp byte [esp+36+28], cl
jz .doit
; create directory
mov byte [edi+11], 10h ; attributes: folder
mov esi, edi
lea eax, [esp+8]
call dword [eax+16] ; flush directory
mov eax, [esp+36+20] ; extract saved cluster
mov [esp+36+20], edi ; this is needed for calculating arg of add_disk_free_space!
push ecx
mov ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
shl ecx, 9
push ecx
push edi
jmp .doit2
.doit:
mov esi, [esp+36+20]
lea eax, [esp+8]
call dword [eax+16] ; flush directory
push ecx
mov ecx, [esp+4+36+24]
push ecx
push edi
test ecx, ecx
jz .done
call get_free_FAT
jc .diskfull
.doit2:
push eax
mov [edi+26], ax
shr eax, 16
mov [edi+20], ax
lea eax, [esp+16+8]
call dword [eax+16] ; flush directory
pop eax
push edx
mov edx, [ebp+FAT.fatEND]
call set_FAT
pop edx
.write_cluster:
push eax
dec eax
dec eax
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
push [ebp+FAT.SECTORS_PER_CLUSTER]
; write data
.write_sector:
cmp byte [esp+20+36+28], 0
jnz .writedir
mov ecx, 512
cmp dword [esp+12], ecx
jb .writeshort
; we can write directly from given buffer
mov ebx, esi
add esi, ecx
jmp .writecommon
.writeshort:
mov ecx, [esp+12]
push ecx
lea edi, [ebp+FAT.buffer]
mov ebx, edi
rep movsb
.writedircont:
lea ecx, [ebp+FAT.buffer+0x200]
sub ecx, edi
push eax
xor eax, eax
rep stosb
pop eax
pop ecx
.writecommon:
push eax
call fs_write32_app
test eax, eax
pop eax
jnz .writeerr
inc eax
sub dword [esp+12], ecx
jz .writedone
dec dword [esp]
jnz .write_sector
pop eax
; allocate new cluster
pop eax
mov ecx, eax
call get_free_FAT
jc .diskfull
push edx
mov edx, [ebp+FAT.fatEND]
call set_FAT
xchg eax, ecx
mov edx, ecx
call set_FAT
pop edx
xchg eax, ecx
jmp .write_cluster
.diskfull:
mov eax, ERROR_DISK_FULL
jmp .ret
.writeerr:
pop eax eax
sub esi, ecx
mov eax, ERROR_DEVICE
jmp .ret
.writedone:
pop eax eax
.done:
xor eax, eax
.ret:
pop edi ecx
sub esi, [esp+4+36+20]
mov [esp+4+36+28], eax
mov [esp+4+36+16], esi
lea eax, [esp+12]
call dword [eax+8]
mov [edi+28], esi
call dword [eax+16]
mov [esp+36+16], ebx
lea eax, [esi+511]
shr eax, 9
mov ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
lea eax, [eax+ecx-1]
xor edx, edx
div ecx
pop ecx
sub ecx, eax
call add_disk_free_space
add esp, 36
call update_disk
call fat_unlock
popad
ret
.writedir:
push 512
lea edi, [ebp+FAT.buffer]
mov ebx, edi
mov ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
shl ecx, 9
cmp ecx, [esp+16]
jnz .writedircont
dec dword [esp+20]
push esi
mov ecx, 32/4
rep movsd
pop esi
mov dword [edi-32], '. '
mov dword [edi-32+4], ' '
mov dword [edi-32+8], ' '
mov byte [edi-32+11], 10h
push esi
mov ecx, 32/4
rep movsd
pop esi
mov dword [edi-32], '.. '
mov dword [edi-32+4], ' '
mov dword [edi-32+8], ' '
mov byte [edi-32+11], 10h
mov ecx, [esp+20+36]
cmp ecx, [ebp+FAT.ROOT_CLUSTER]
jnz @f
xor ecx, ecx
@@:
mov word [edi-32+26], cx
shr ecx, 16
mov [edi-32+20], cx
jmp .writedircont
fat_Write.access_denied:
push ERROR_ACCESS_DENIED
fat_Write.ret0:
pop eax
xor ebx, ebx
ret
fat_Write.ret11:
push ERROR_DEVICE
jmp fat_Write.ret0
;----------------------------------------------------------------
; fat_Write - FAT16/32 implementation of writing to file
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_Write:
cmp byte [esi], 0
jz .access_denied
call fat_lock
push edi
stdcall hd_find_lfn, [esp+4+4]
jnc .found
pop edi
push eax
call fat_unlock
jmp .ret0
.found:
; FAT does not support files larger than 4GB
cmp dword [ebx+8], 0
jz @f
.eof:
pop edi
push ERROR_END_OF_FILE
call fat_unlock
jmp .ret0
@@:
mov ecx, [ebx+12]
mov edx, [ebx+16]
mov ebx, [ebx+4]
; now edi points to direntry, ebx=start byte to write,
; ecx=number of bytes to write, edx=data pointer
; extend file if needed
add ecx, ebx
jc .eof ; FAT does not support files larger than 4GB
push edx
push eax ; save directory sector
push 0 ; return value=0
call get_time_for_file
mov [edi+22], ax ; last write time
call get_date_for_file
mov [edi+24], ax ; last write date
mov [edi+18], ax ; last access date
push dword [edi+28] ; save current file size
cmp ecx, [edi+28]
jbe .length_ok
cmp ecx, ebx
jz .length_ok
call hd_extend_file
jnc .length_ok
mov [esp+4], eax
; hd_extend_file can return three error codes: FAT table error, device error or disk full.
; First two cases are fatal errors, in third case we may write some data
cmp al, ERROR_DISK_FULL
jz .disk_full
call fat_unlock
pop eax
pop eax
pop ecx
pop edx
pop edi
xor ebx, ebx
ret
.disk_full:
; correct number of bytes to write
mov ecx, [edi+28]
cmp ecx, ebx
ja .length_ok
push 0
.ret:
pop eax
sub edx, [esp+12]
mov ebx, edx ; ebx=number of written bytes
call update_disk
test eax, eax
jz @f
mov byte [esp+4], ERROR_DEVICE
@@:
call fat_unlock
pop eax
pop eax
pop ecx
pop edx
pop edi
ret
.length_ok:
mov esi, [edi+28]
mov eax, [edi+20-2]
mov ax, [edi+26]
mov edi, eax ; edi=current cluster
push 0 ; current sector in cluster
; save directory
mov eax, [esp+12]
push ebx
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
pop ebx
test eax, eax
jz @f
.device_err:
mov byte [esp+8], ERROR_DEVICE
jmp .ret
.fat_err:
mov byte [esp+8], ERROR_FAT_TABLE
jmp .ret
@@:
; now ebx=start pos, ecx=end pos, both lie inside file
sub ecx, ebx
jz .ret
.write_loop:
; skip unmodified sectors
cmp dword [esp+4], 0x200
jb .modify
sub ebx, 0x200
jae .skip
add ebx, 0x200
.modify:
; get length of data in current sector
push ecx
sub ebx, 0x200
jb .hasdata
neg ebx
xor ecx, ecx
jmp @f
.hasdata:
neg ebx
cmp ecx, ebx
jbe @f
mov ecx, ebx
@@:
; get current sector number
mov eax, edi
dec eax
dec eax
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
add eax, [esp+4]
; load sector if needed
cmp dword [esp+8], 0 ; we don't need to read uninitialized data
jz .noread
cmp ecx, 0x200 ; we don't need to read sector if it is fully rewritten
jz .noread
cmp ecx, esi ; (same for the last sector)
jz .noread
push eax ebx
lea ebx, [ebp+FAT.buffer]
call fs_read32_app
test eax, eax
pop ebx eax
jz @f
.device_err2:
pop ecx
jmp .device_err
@@:
.noread:
; zero uninitialized data if file was extended (because hd_extend_file does not this)
push eax ecx edi
xor eax, eax
mov ecx, 0x200
sub ecx, [esp+8+12]
jbe @f
lea edi, [ebp+FAT.buffer]
add edi, [esp+8+12]
rep stosb
@@:
; zero uninitialized data in the last sector
mov ecx, 0x200
sub ecx, esi
jbe @f
lea edi, [ebp+FAT.buffer+esi]
rep stosb
@@:
pop edi ecx
; copy new data
mov eax, edx
neg ebx
jecxz @f
lea ebx, [ebp+FAT.buffer+0x200+ebx]
call memmove
xor ebx, ebx
@@:
pop eax
; save sector
push ebx
lea ebx, [ebp+FAT.buffer]
call fs_write32_app
pop ebx
test eax, eax
jnz .device_err2
add edx, ecx
sub [esp], ecx
pop ecx
jz .ret
.skip:
; next sector
pop eax
inc eax
push eax
cmp eax, [ebp+FAT.SECTORS_PER_CLUSTER]
jb @f
and dword [esp], 0
mov eax, edi
call get_FAT
mov edi, eax
jc .device_err
cmp edi, 2
jb .fat_err
cmp edi, [ebp+FAT.fatRESERVED]
jae .fat_err
@@:
sub esi, 0x200
jae @f
xor esi, esi
@@:
sub dword [esp+4], 0x200
jae @f
and dword [esp+4], 0
@@:
jmp .write_loop
hd_extend_file.zero_size:
xor eax, eax
jmp hd_extend_file.start_extend
; extends file on hd to given size (new data area is undefined)
; in: edi->direntry, ecx=new size
; out: CF=0 => OK, eax=0
; CF=1 => error, eax=code (ERROR_FAT_TABLE or ERROR_DISK_FULL or ERROR_DEVICE)
hd_extend_file:
push esi
mov esi, [ebp+FAT.SECTORS_PER_CLUSTER]
imul esi, [ebp+FAT.BYTES_PER_SECTOR]
push ecx
; find the last cluster of file
mov eax, [edi+20-2]
mov ax, [edi+26]
mov ecx, [edi+28]
jecxz .zero_size
.last_loop:
sub ecx, esi
jbe .last_found
call get_FAT
jnc @f
.device_err:
pop ecx
.device_err2:
pop esi
push ERROR_DEVICE
.ret_err:
pop eax
stc
ret
@@:
cmp eax, 2
jb .fat_err
cmp eax, [ebp+FAT.fatRESERVED]
jb .last_loop
.fat_err:
pop ecx esi
push ERROR_FAT_TABLE
jmp .ret_err
.last_found:
push eax
call get_FAT
jnc @f
pop eax
jmp .device_err
@@:
cmp eax, [ebp+FAT.fatRESERVED]
pop eax
jb .fat_err
; set length to full number of clusters
sub [edi+28], ecx
.start_extend:
pop ecx
; now do extend
push edx
mov edx, 2 ; start scan from cluster 2
.extend_loop:
cmp [edi+28], ecx
jae .extend_done
; add new cluster
push eax
call get_free_FAT
jc .disk_full
mov edx, [ebp+FAT.fatEND]
call set_FAT
mov edx, eax
pop eax
test eax, eax
jz .first_cluster
push edx
call set_FAT
pop edx
jmp @f
.first_cluster:
ror edx, 16
mov [edi+20], dx
ror edx, 16
mov [edi+26], dx
@@:
push ecx
mov ecx, -1
call add_disk_free_space
pop ecx
mov eax, edx
add [edi+28], esi
jmp .extend_loop
.extend_done:
mov [edi+28], ecx
pop edx esi
xor eax, eax ; CF=0
ret
.device_err3:
pop edx
jmp .device_err2
.disk_full:
pop eax edx esi
movi eax, ERROR_DISK_FULL
stc
ret
;----------------------------------------------------------------
; fat_SetFileEnd - FAT16/32 implementation of setting end-of-file
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_SetFileEnd:
call fat_lock
push edi
cmp byte [esi], 0
jnz @f
.access_denied:
push ERROR_ACCESS_DENIED
.ret:
call fat_unlock
pop eax
pop edi
ret
@@:
stdcall hd_find_lfn, [esp+4+4]
jnc @f
.reteax:
push eax
jmp .ret
@@:
; must not be directory
test byte [edi+11], 10h
jnz .access_denied
; file size must not exceed 4 Gb
cmp dword [ebx+8], 0
jz @f
push ERROR_END_OF_FILE
jmp .ret
@@:
push eax ; save directory sector
; set file modification date/time to current
call fat_update_datetime
mov eax, [ebx+4]
cmp eax, [edi+28]
jb .truncate
ja .expand
pop eax
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
test eax, eax
jz @f
push ERROR_DEVICE
jmp .ret
@@:
push 0
jmp .ret
.expand:
push ebx ebp ecx
push dword [edi+28] ; save old size
mov ecx, eax
call hd_extend_file
push eax ; return code
jnc .expand_ok
cmp al, ERROR_DISK_FULL
jz .disk_full
.pop_ret:
call update_disk
pop eax ecx ecx ebp ebx ecx
jmp .reteax
.expand_ok:
.disk_full:
; save directory
mov eax, [edi+28]
xchg eax, [esp+20]
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
test eax, eax
mov eax, [edi+20-2]
mov ax, [edi+26]
mov edi, eax
jz @f
.pop_ret11:
mov byte [esp], ERROR_DEVICE
jmp .pop_ret
@@:
test edi, edi
jz .pop_ret
; now zero new data
push 0
; edi=current cluster, [esp]=sector in cluster
; [esp+24]=new size, [esp+8]=old size, [esp+4]=return code
.zero_loop:
cmp edi, 2
jb .error_fat
cmp edi, [ebp+FAT.fatRESERVED]
jae .error_fat
sub dword [esp+8], 0x200
jae .next_cluster
lea eax, [edi-2]
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
add eax, [esp]
cmp dword [esp+8], -0x200
jz .noread
push eax
lea ebx, [ebp+FAT.buffer]
call fs_read32_app
test eax, eax
pop eax
jnz .err_next
.noread:
mov ecx, [esp+8]
neg ecx
push edi
lea edi, [ebp+FAT.buffer+0x200]
add edi, [esp+12]
push eax
xor eax, eax
mov [esp+16], eax
rep stosb
pop eax
pop edi
call fs_write32_app
test eax, eax
jz .next_cluster
.err_next:
mov byte [esp+4], ERROR_DEVICE
.next_cluster:
pop eax
sub dword [esp+20], 0x200
jbe .pop_ret
inc eax
push eax
cmp eax, [ebp+FAT.SECTORS_PER_CLUSTER]
jb .zero_loop
and dword [esp], 0
mov eax, edi
call get_FAT
mov edi, eax
jnc .zero_loop
pop eax
jmp .pop_ret11
.truncate:
mov [edi+28], eax
push ecx
mov ecx, [edi+20-2]
mov cx, [edi+26]
push eax
test eax, eax
jz .zero_size
; find new last cluster
@@:
cmp ecx, 2
jb .error_fat2
cmp ecx, [ebp+FAT.fatRESERVED]
jae .error_fat2
mov eax, [ebp+FAT.SECTORS_PER_CLUSTER]
shl eax, 9
sub [esp], eax
jbe @f
mov eax, ecx
call get_FAT
mov ecx, eax
jnc @b
.device_err3:
pop eax ecx eax edi
call update_disk
call fat_unlock
movi eax, ERROR_DEVICE
ret
@@:
; we will zero data at the end of last sector - remember it
push ecx
; terminate FAT chain
push edx
mov eax, ecx
mov edx, [ebp+FAT.fatEND]
call set_FAT
mov eax, edx
pop edx
jnc @f
.device_err4:
pop ecx
jmp .device_err3
.zero_size:
and word [edi+20], 0
and word [edi+26], 0
push 0
mov eax, ecx
@@:
; delete FAT chain
call clear_cluster_chain
jc .device_err4
; save directory
mov eax, [esp+12]
push ebx
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
pop ebx
test eax, eax
jnz .device_err4
; zero last sector, ignore errors
pop ecx
pop eax
dec ecx
imul ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
add ecx, [ebp+FAT.DATA_START]
push eax
sar eax, 9
add ecx, eax
pop eax
and eax, 0x1FF
jz .truncate_done
push ebx eax
mov eax, ecx
lea ebx, [ebp+FAT.buffer]
call fs_read32_app
pop eax
lea edi, [ebp+FAT.buffer+eax]
push ecx
mov ecx, 0x200
sub ecx, eax
xor eax, eax
rep stosb
pop eax
call fs_write32_app
pop ebx
.truncate_done:
pop ecx eax edi
call update_disk
call fat_unlock
xor eax, eax
ret
.error_fat:
pop eax
mov byte [esp], ERROR_FAT_TABLE
jmp .pop_ret
.error_fat2:
pop eax ecx eax edi
call update_disk
call fat_unlock
movi eax, ERROR_FAT_TABLE
ret
;----------------------------------------------------------------
; fat_GetFileInfo - FAT16/32 implementation of getting file info
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_GetFileInfo:
cmp byte [esi], 0
jnz @f
mov eax, 2
ret
@@:
push edi
call fat_lock
stdcall hd_find_lfn, [esp+4+4]
jc .error
push ebp
xor ebp, ebp
mov esi, [ebx+16]
mov dword [esi+4], ebp
call fat_entry_to_bdfe2
pop ebp
call fat_unlock
xor eax, eax
pop edi
ret
.error:
push eax
call fat_unlock
pop eax
pop edi
ret
;----------------------------------------------------------------
; fat_SetFileInfo - FAT16/32 implementation of setting file info
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_SetFileInfo:
cmp byte [esi], 0
jnz @f
mov eax, 2
ret
@@:
push edi
call fat_lock
stdcall hd_find_lfn, [esp+4+4]
jc .error
push eax
mov edx, [ebx+16]
call bdfe_to_fat_entry
pop eax
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
call update_disk
call fat_unlock
pop edi
xor eax, eax
ret
.error:
push eax
call fat_unlock
pop eax
pop edi
ret
;----------------------------------------------------------------
; fat_Delete - FAT16/32 implementation of deleting a file/folder
; in: ebp = pointer to FAT structure
; in: esi+[esp+4] = name
; in: ebx = pointer to parameters from sysfunc 70
; out: eax, ebx = return values for sysfunc 70
;----------------------------------------------------------------
fat_Delete:
call fat_lock
cmp byte [esi], 0
jnz @f
; cannot delete root!
.access_denied:
push ERROR_ACCESS_DENIED
.pop_ret:
call fat_unlock
pop eax
xor ebx, ebx
ret
@@:
and [ebp+FAT.longname_sec1], 0
and [ebp+FAT.longname_sec2], 0
push edi
stdcall hd_find_lfn, [esp+4+4]
jnc .found
pop edi
push ERROR_FILE_NOT_FOUND
jmp .pop_ret
.found:
cmp dword [edi], '. '
jz .access_denied2
cmp dword [edi], '.. '
jz .access_denied2
test byte [edi+11], 10h
jz .dodel
; we can delete only empty folders!
pushad
mov esi, [edi+20-2]
mov si, [edi+26]
xor ecx, ecx
lea eax, [esi-2]
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
lea ebx, [ebp+FAT.buffer]
call fs_read32_sys
test eax, eax
jnz .err1
lea eax, [ebx+0x200]
add ebx, 2*0x20
.checkempty:
cmp byte [ebx], 0
jz .empty
cmp byte [ebx], 0xE5
jnz .notempty
add ebx, 0x20
cmp ebx, eax
jb .checkempty
inc ecx
cmp ecx, [ebp+FAT.SECTORS_PER_CLUSTER]
jb @f
mov eax, esi
call get_FAT
jc .err1
cmp eax, 2
jb .error_fat
cmp eax, [ebp+FAT.fatRESERVED]
jae .empty
mov esi, eax
xor ecx, ecx
@@:
lea eax, [esi-2]
imul eax, [ebp+FAT.SECTORS_PER_CLUSTER]
add eax, [ebp+FAT.DATA_START]
add eax, ecx
lea ebx, [ebp+FAT.buffer]
call fs_read32_sys
test eax, eax
lea eax, [ebx+0x200]
jz .checkempty
.err1:
popad
.err2:
pop edi
call fat_unlock
movi eax, ERROR_DEVICE
ret
.error_fat:
popad
pop edi
call fat_unlock
movi eax, ERROR_FAT_TABLE
ret
.notempty:
popad
.access_denied2:
pop edi
call fat_unlock
movi eax, ERROR_ACCESS_DENIED
ret
.empty:
popad
push eax ebx
lea ebx, [ebp+FAT.buffer]
call fs_read32_sys
test eax, eax
pop ebx eax
jnz .err2
.dodel:
push eax
mov eax, [edi+20-2]
mov ax, [edi+26]
xchg eax, [esp]
; delete folder entry
mov byte [edi], 0xE5
; delete LFN (if present)
.lfndel:
lea edx, [ebp+FAT.buffer]
cmp edi, edx
ja @f
cmp [ebp+FAT.longname_sec2], 0
jz .lfndone
push [ebp+FAT.longname_sec2]
push [ebp+FAT.longname_sec1]
pop [ebp+FAT.longname_sec2]
and [ebp+FAT.longname_sec1], 0
push ebx
mov ebx, edx
call fs_write32_sys
mov eax, [esp+4]
call fs_read32_sys
pop ebx
pop eax
lea edi, [ebp+FAT.buffer+0x200]
@@:
sub edi, 0x20
cmp byte [edi], 0xE5
jz .lfndone
cmp byte [edi+11], 0xF
jnz .lfndone
mov byte [edi], 0xE5
jmp .lfndel
.lfndone:
push ebx
lea ebx, [ebp+FAT.buffer]
call fs_write32_sys
pop ebx
; delete FAT chain
pop eax
call clear_cluster_chain
call update_disk
call fat_unlock
pop edi
xor eax, eax
ret
; \end{diamond}