Spaceraven/kolibrios
1
0
Fork 0
forked from KolibriOS/kolibrios
Code Pull Requests Activity
0b65f18e93
kolibrios/kernel/trunk/fs/fat32.inc
Evgeny Grechnikov (Diamond) 0b65f18e93 Some corrections in new file system functions. Added sysfuncr.txt docs. 
git-svn-id: svn://kolibrios.org@77 a494cfbc-eb01-0410-851d-a64ba20cac60
2006-05-10 14:30:38 +00:00

3368 lines
85 KiB
PHP
Raw Blame History

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; FAT32.INC ;;
;; ;;
;; FAT16/32 functions for MenuetOS ;;
;; ;;
;; Copyright 2002 Paolo Minazzi, paolo.minazzi@inwind.it ;;
;; ;;
;; See file COPYING for details ;;
;; 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 ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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]
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
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
include 'part_set.inc'
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
cmp [hd_error],0
jne sfc_error
sfc_no_change:
mov [fat_in_cache],eax ; save fat sector
call hd_read
cmp [hd_error],0
jne sfc_error
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
cmp [hd_error],0
jne hd_error_01
gfc_no_change:
mov [fat_in_cache],eax
call hd_read
cmp [hd_error],0
jne hd_error_01
gfc_in_cache:
mov eax,[ebx+esi]
and eax,[fatMASK]
hd_error_01:
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
cmp [hd_error],0
jne 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_1:
add esp,4
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
cmp [hd_error],0
jne write_fat_not_used
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
cmp [hd_error],0
jne adr_not_found
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 [hd_error],0
jne adr_not_found
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
cmp [hd_error],0
jne adw_not_found
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 [hd_error],0
jne adw_not_found
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
cmp [hd_error],0
jne adw_not_found
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
cmp [hd_error],0
jne adw_not_found_1
mov [f_del],0
mov ecx,-1 ; remove 1 cluster from free disk space
call add_disk_free_space
cmp [hd_error],0
jne adw_not_found_1
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
cmp [hd_error],0
jne adw_not_found_1
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_1:
add esp,4
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
cmp [hd_error],0
jne gdc_error
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
cmp [hd_error],0
jne sdc_error
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
cmp [hd_error],0
jne make_dir_error_1
make_dir_path_not_found:
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne make_dir_error_2
mov [hd1_status],0
mov eax,ERROR_FILE_NOT_FOUND
ret
make_dir_disk_full:
cmp [hd_error],0
jne make_dir_error_1
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne make_dir_error_2
mov [hd1_status],0
mov eax,ERROR_DISK_FULL
ret
make_dir_already_exist:
cmp [hd_error],0
jne make_dir_error_1
mov eax,[cluster] ; directory cluster
xor edx,edx ; free
mov [f_del],1
call set_FAT
cmp [hd_error],0
jne make_dir_error_1
mov [f_del],0
popad
call update_disk ; write all of cache and fat to hd
make_dir_error_2:
mov [hd1_status],0
mov eax,ERROR_ACCESS_DENIED
ret
make_dir_error_1:
popad
jmp make_dir_error_2
make_dir_error_3:
add esp,4
jmp make_dir_error_1
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
cmp [hd_error],0
jne make_dir_error_3
pop eax
mov ebx,PUSHAD_EAX ; dir name
push eax
call analyze_directory ; check if directory already exist
cmp [hd_error],0
jne make_dir_error_1
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
cmp [hd_error],0
jne make_dir_error_1
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
cmp [hd_error],0
jne make_dir_error_1
dec edx
jnz dir_set_empty_directory
mov ecx,-1 ; remove 1 cluster from free disk space
call add_disk_free_space
cmp [hd_error],0
jne make_dir_error_1
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne make_dir_error_2
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
cmp [hd_error],0
jne @f
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 [hd_error],0
jne add_not_fs
cmp dword [ebx+0x1fc],0xaa550000 ; check sector id
jne add_not_fs
add [ebx+0x1e8],ecx
call hd_write
cmp [hd_error],0
jne add_not_fs
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
cmp [hd_error],0
jne append_access
push eax ; save first cluster
mov eax,[sector_tmp]
mov ebx,buffer
call hd_write ; write new file entry back to disk
cmp [hd_error],0
jne append_access_1
pop eax
append_remove_free:
mov ecx,-1 ; remove 1 cluster from free disk space
call add_disk_free_space ; Note: uses buffer
cmp [hd_error],0
jne append_access
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:
cmp [hd_error],0
jne append_access
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
cmp [hd_error],0
jne append_access_1
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 [hd_error],0
jne append_access
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 [hd_error],0
jne append_access
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
cmp [hd_error],0
jne append_access_1
mov edx,eax
mov eax,[cluster]
mov [f_del],1
call set_FAT ; update previous cluster
cmp [hd_error],0
jne append_access_1
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:
cmp [hd_error],0
jne append_access
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
cmp [hd_error],0
jne append_access
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
cmp [hd_error],0
jne append_access
sub ecx,PUSHAD_ESI ; start position
mov PUSHAD_EBX,ecx ; bytes written
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne append_access_2
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:
cmp [hd_error],0
jne append_access
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
append_access_1:
add esp,4
append_access:
popad
append_access_2:
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
cmp [hd_error],0
jne append_access
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
cmp [hd_error],0
jne append_access
jmp truncate_new_cluster
truncate_pos_found:
mov edx,[fatEND] ; new end for cluster chain
mov [f_del],1
call set_FAT
cmp [hd_error],0
jne append_access
mov [f_del],0
mov eax,edx ; clear rest of chain
truncate_clear_chain:
call clear_cluster_chain
cmp [hd_error],0
jne append_access
truncate_eof:
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne append_access_2
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
cmp [hd_error],0
jne filepos_eof
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
cmp [hd_error],0
jne exit_write_access_1
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
cmp [hd_error],0
jne exit_write_access
exit_writing_with_error:
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne exit_write_access_2
mov [hd1_status],0
mov eax,ERROR_FILE_NOT_FOUND
ret
exit_writing_disk_full_clear:
cmp [hd_error],0
jne exit_write_access_1
mov eax,[sector_tmp]
mov ebx,buffer
call hd_read ; read directory sector
cmp [hd_error],0
jne exit_write_access_1
mov edx,[entry_pos]
mov byte [edx],0xe5 ; mark as deleted
call hd_write
cmp [hd_error],0
jne exit_write_access_1
mov eax,[edx+20-2] ; FAT entry
mov ax,[edx+26]
and eax,[fatMASK]
call clear_cluster_chain
exit_writing_disk_full:
cmp [hd_error],0
jne exit_write_access_1
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne exit_write_access_2
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
exit_write_access_1:
popad
exit_write_access_2:
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
cmp [hd_error],0
jne exit_write_access_1
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
cmp [hd_error],0
jne exit_write_access_1
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
cmp [hd_error],0
jne exit_write_access_1
dec ecx ; update cluster count
jmp hd_new_block_write
file_saved_OK:
mov edx,[fatEND] ; new end for cluster chain
call set_FAT
cmp [hd_error],0
jne exit_write_access_1
dec ecx ; update cluster count
call add_disk_free_space ; remove clusters from free disk space
cmp [hd_error],0
jne exit_write_access_1
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne exit_write_access_2
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
; 10 - access denied
; 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
cmp [hd_error],0
jne file_access_denied
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
cmp [hd_error],0
jne file_access_denied
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 [hd_error],0
jne file_access_denied
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:
cmp [hd_error],0
jne file_access_denied
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:
cmp [hd_error],0
jne file_access_denied
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
file_access_denied:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_ACCESS_DENIED
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
cmp [hd_error],0
jne dir_size_ret
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
cmp [hd_error],0
jne delete_no_access_1
pop ebx
delete_notdir:
call delete_entry_name
cmp [hd_error],0
jne delete_no_access
mov eax,ecx ; first cluster of file
call clear_cluster_chain
cmp [hd_error],0
jne delete_no_access
popad
xor eax,eax
ret
delete_no_access_1:
add esp,4
delete_no_access:
popad
mov eax,ERROR_ACCESS_DENIED
ret
file_to_delete_not_found:
cmp [hd_error],0
jne delete_no_access
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
cmp [hd_error],0
jne 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
access_denied_01:
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
cmp [hd_error],0
jne clear_error
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
cmp [hd_error],0
jne clear_error
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
cmp [hd_error],0
jne clear_error_1
pop ebx eax
clear_file:
call clear_cluster_chain
cmp [hd_error],0
jne clear_error
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
cmp [hd_error],0
jne clear_error
inc eax ; next sector
dec ecx
jnz clear_new_sector
mov eax,esi
call get_FAT ; get next cluster
cmp [hd_error],0
jne clear_error
jmp clear_new_cluster ; clear it
clear_write_last:
mov eax,edi
mov ebx,deltree_buffer
call hd_write ; write directory sector to disk
cmp [hd_error],0
jne clear_error
clear_end:
popad
clc
ret
clear_error_1:
add esp,8
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
cmp [hd_error],0
jne delete_name_end
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
cmp [hd_error],0
jne delete_name_end
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
cmp [hd_error],0
jne rename_entry_already_exist_1
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
cmp [hd_error],0
jne rename_entry_already_exist
rename_not_dir:
cmp [hd_error],0
jne rename_entry_already_exist
mov eax,[sector_tmp]
mov ebx,buffer
call hd_read ; read source directory sector
cmp [hd_error],0
jne rename_entry_already_exist
mov ebx,[entry_pos]
call delete_entry_name
cmp [hd_error],0
jne rename_entry_already_exist
popad
call update_disk ; write all of cache and fat to hd
cmp [hd_error],0
jne rename_entry_already_exist_2
mov [hd1_status],0
xor eax,eax
ret
rename_entry_not_found:
cmp [hd_error],0
jne rename_entry_already_exist
popad
mov [hd1_status],0
mov eax,ERROR_FILE_NOT_FOUND
ret
rename_entry_already_exist_1:
add esp,8
rename_entry_already_exist:
popad
rename_entry_already_exist_2:
mov [hd1_status],0
mov eax,ERROR_ACCESS_DENIED
ret
rename_disk_full:
cmp [hd_error],0
jne rename_entry_already_exist
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 [hd_error],0
jne not_2dot
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
; 10 - access denied
; 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
cmp [hd_error],0
jne get_filesize_access_denied
get_filesize_set_size:
mov PUSHAD_EBX,eax
popad
mov [hd1_status],0
xor eax,eax
ret
get_filesize_not_found:
cmp [hd_error],0
jne get_filesize_access_denied
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_filesize_access_denied:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_ACCESS_DENIED
ret
get_fileattr:
;-----------------------------------------------------------
; input : eax = file name
; edx = path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 10 - access denied
; 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:
cmp [hd_error],0
jne get_fileattr_access_denied
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_fileattr_access_denied:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_ACCESS_DENIED
ret
get_filedate:
;-----------------------------------------------------------
; input : eax = file name
; edx = path
; output : eax = 0 - ok
; 3 - unknown FS
; 5 - file not found
; 10 - access denied
; 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:
cmp [hd_error],0
jne get_filedate_access_denied
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_FILE_NOT_FOUND
ret
get_filedate_access_denied:
popad
mov [hd1_status],0
xor ebx,ebx
mov eax,ERROR_ACCESS_DENIED
ret
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 [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
cmp [hd_error],0
jne 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,[SECTORS_PER_CLUSTER],512 ; cluster size in bytes
mov [hd1_status],0
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
update_disk:
;-----------------------------------------------------------
; write changed fat and cache to disk
;-----------------------------------------------------------
cmp [fat_change],0 ; is fat changed?
je upd_no_change
call write_fat_sector
cmp [hd_error],0
jne update_disk_acces_denied
upd_no_change:
call write_cache
update_disk_acces_denied:
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
cmp [hd_error],0
jne return_01
push eax edx
call wait_for_hd_idle
cmp [hd_error],0
jne hd_read_error
cli
xor eax,eax
mov edx,[hdbase]
inc edx
out dx,al ; ATAFeatures <20><><EFBFBD>𡢠 "<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>"
inc edx
inc eax
out dx,al ; ATASectorCount <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
inc edx
mov eax,[esp+4]
out dx,al ; ATASectorNumber <20><><EFBFBD>𡢠 <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
shr eax,8
inc edx
out dx,al ; ATACylinder <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>𭤠<EFBFBD> (<28><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>)
shr eax,8
inc edx
out dx,al ; <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD>𭤠<EFBFBD> (<28><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD>)
shr eax,8
inc edx
and al,1+2+4+8
add al,byte [hdid]
add al,128+64+32
out dx,al ; <20><><EFBFBD><EFBFBD><EFBFBD> <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>/<2F><><EFBFBD><EFBFBD><EFBFBD> <20>𡪠
inc edx
mov al,20h
out dx,al ; ATACommand <20><><EFBFBD>𡢠 <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
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
return_01:
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
cmp [hd_error],0
jne hd_write_access_denied
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
hd_write_access_denied:
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
cmp [hd_error],0
jne hd_write_error
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
return_02:
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
cmp [hd_error],0
jne found_slot_access_denied
jmp search_again ; and start again
found_slot:
mov [cache_search_start],edi
found_slot_access_denied:
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
mov [hd_error],0
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
hd_lba_str db 'K : FS - HD LBA 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 $
mov [hd_error],1
pop eax
ret
hd_read_error:
call clear_hd_cache
call clear_application_table_status
mov esi,hd_read_str
call sys_msg_board_str
pop edx eax
jmp return_01
; jmp $
hd_write_error:
call clear_hd_cache
call clear_application_table_status
mov esi,hd_write_str
call sys_msg_board_str
jmp return_02
; jmp $
hd_lba_error:
call clear_hd_cache
call clear_application_table_status
mov esi,hd_lba_str
call sys_msg_board_str
jmp LBA_read_ret
wait_for_hd_idle:
push eax edx
call save_hd_wait_timeout
mov edx,[hdbase]
add edx,0x7
wfhil1:
call check_hd_wait_timeout
cmp [hd_error],0
jne @f
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
cmp [hd_error],0
jne @f
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
; \begin{diamond}
hd_find_lfn:
; in: esi->name
; out: CF=1 - file not found
; else CF=0 and edi->direntry
pusha
sub esp, 262*2 ; allocate space for LFN
mov ebp, esp
push 0 ; for fat_get_name: read ASCII name
mov eax, [ROOT_CLUSTER] ; start from root
.mainloop:
.new_cluster:
mov [cluster_tmp], eax
mov [fat16_root], 0
cmp eax, [LAST_CLUSTER]
ja .notfound
cmp eax, 2
jae .data_cluster
cmp [fat_type], 16
jnz .notfound
mov eax, [ROOT_START]
mov ecx, [ROOT_SECTORS]
mov [fat16_root], 1
jmp .new_sector
.data_cluster:
dec eax
dec eax
mov ecx, [SECTORS_PER_CLUSTER]
mul ecx
add eax, [DATA_START]
.new_sector:
mov ebx, buffer
call hd_read
cmp [hd_error],0
jne .notfound
mov edi, ebx
add ebx, 512
push eax
.l1:
call fat_get_name
jc .l2
call fat_compare_name
jz .found
.l2:
add edi, 0x20
cmp edi, ebx
jb .l1
pop eax
inc eax
loop .new_sector
cmp [fat16_root], 0
jnz .notfound
mov eax, [cluster_tmp]
call get_FAT
cmp [hd_error],0
jne .notfound
cmp eax, 2
jb .notfound
cmp eax, [fatRESERVED]
jb .new_cluster
.notfound:
add esp, 262*2+4
popa
stc
ret
.found:
pop eax
; if this is LFN entry, advance to true entry
cmp byte [edi+11], 0xF
jnz .entryfound
add edi, 0x20
cmp edi, ebx
jb .entryfound
inc eax
dec ecx
jnz .read_entry
cmp [fat16_root], 0
jnz .notfound
mov eax, [cluster_tmp]
call get_FAT
cmp [hd_error],0
jne .notfound
cmp eax, 2
jb .notfound
cmp eax, [fatRESERVED]
jae .notfound
dec eax
dec eax
mul [SECTORS_PER_CLUSTER]
add eax, [DATA_START]
.read_entry:
mov ebx, [buffer]
call hd_read
cmp [hd_error],0
jne .notfound
mov edi, ebx
.entryfound:
cmp byte [esi], 0
jz .done
test byte [edi+11], 10h ; is a directory?
jz .notfound
mov eax, [edi+20-2]
mov ax, [edi+26]
jmp .mainloop
.done:
add esp, 262*2+4+4 ; CF=0
push edi
popad
ret
;----------------------------------------------------------------
;
; fs_HdRead - LFN variant for reading hard disk
;
; esi points to filename
; ebx pointer to 64-bit number = first wanted byte, 0+
; may be ebx=0 - start from first byte
; ecx number of bytes to read, 0+
; edx mem location to return data
;
; ret ebx = bytes read or 0xffffffff file not found
; eax = 0 ok read or other = errormsg
;
;--------------------------------------------------------------
fs_HdRead:
cmp [fat_type], 0
jnz @f
or ebx, -1
mov eax, ERROR_UNKNOWN_FS
ret
@@:
push edi
cmp byte [esi], 0
jnz @f
.noaccess:
pop edi
.noaccess_2:
or ebx, -1
mov eax, ERROR_ACCESS_DENIED
ret
.noaccess_3:
add esp,4
.noaccess_1:
add esp,4
.noaccess_4:
add esp,4*5
jmp .noaccess_2
@@:
call hd_find_lfn
jnc .found
pop edi
cmp [hd_error],0
jne .noaccess_2
or ebx, -1
mov eax, ERROR_FILE_NOT_FOUND
ret
.found:
test byte [edi+11], 0x10 ; do not allow read directories
jnz .noaccess
test ebx, ebx
jz .l1
cmp dword [ebx+4], 0
jz @f
xor ebx, ebx
.reteof:
mov eax, 6
pop edi
ret
@@:
mov ebx, [ebx]
.l1:
push ecx 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
test eax, eax
jz .eof
cmp eax, [fatRESERVED]
jae .eof
mov [cluster_tmp], eax
dec eax
dec eax
mov edi, [SECTORS_PER_CLUSTER]
imul eax, edi
add eax, [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 ebx
mov ebx, edx
call hd_read
cmp [hd_error],0
jne .noaccess_1
pop ebx
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
mov ebx, buffer
call hd_read
cmp [hd_error],0
jne .noaccess_3
mov eax, ebx
pop ebx
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, [cluster_tmp]
call get_FAT
cmp [hd_error],0
jne .noaccess_4
jmp .new_cluster
.done:
mov ebx, edx
pop eax edx ecx edi
sub ebx, edx
ret
.eof:
mov ebx, edx
pop eax edx ecx
sub ebx, edx
jmp .reteof
;----------------------------------------------------------------
;
; fs_HdReadFolder - LFN variant for reading hard disk folder
;
; esi points to filename
; ebx pointer to 32-bit number = first wanted block, 0+
; ecx number of blocks to read, 0+
; edx mem location to return data
;
; ret ebx = blocks read or 0xffffffff folder not found
; eax = 0 ok read or other = errormsg
;
;--------------------------------------------------------------
fs_HdReadFolder:
mov ebx, [ebx]
mov eax, [ROOT_CLUSTER]
push edi
cmp byte [esi], 0
jz .doit
call hd_find_lfn
jnc .found
pop edi
or ebx, -1
mov eax, ERROR_FILE_NOT_FOUND
ret
.found:
test byte [edi+11], 0x10 ; do not allow read files
jnz .found_dir
pop edi
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 ecx
push ebp
sub esp, 262*2 ; reserve space for LFN
mov ebp, esp
push 1 ; for fat_get_name: read UNICODE name
; init header
push eax ecx
mov edi, edx
mov ecx, 32/4
xor eax, eax
rep stosd
pop ecx eax
mov byte [edx], 1 ; version
mov esi, edi ; esi points to BDFE
.new_cluster:
mov [cluster_tmp], eax
test eax, eax
jnz @f
cmp [fat_type], 32
jz .notfound
mov eax, [ROOT_START]
push [ROOT_SECTORS]
push ebx
jmp .new_sector
@@:
dec eax
dec eax
imul eax, [SECTORS_PER_CLUSTER]
push [SECTORS_PER_CLUSTER]
add eax, [DATA_START]
push ebx
.new_sector:
mov ebx, buffer
mov edi, ebx
call hd_read
cmp [hd_error], 0
jnz .notfound2
add ebx, 512
push eax
.l1:
call fat_get_name
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, [cluster_tmp]
test eax, eax
jz .done
call get_FAT
cmp [hd_error], 0
jnz .notfound2
cmp eax, 2
jb .done
cmp eax, [fatRESERVED]
jae .done
push eax
mov eax, [SECTORS_PER_CLUSTER]
mov [esp+8], eax
pop eax
mov [cluster_tmp], eax
dec eax
dec eax
imul eax, [SECTORS_PER_CLUSTER]
add eax, [DATA_START]
@@:
mov ebx, buffer
mov edi, ebx
call hd_read
cmp [hd_error], 0
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
call fat_entry_to_bdfe
.l2:
add edi, 0x20
cmp edi, ebx
jb .l1
pop eax
inc eax
dec dword [esp+4]
jnz .new_sector
mov eax, [cluster_tmp]
test eax, eax
jz .done
call get_FAT
cmp [hd_error], 0
jnz .notfound2
cmp eax, 2
jb .done
cmp eax, [fatRESERVED]
jae .done
push eax
mov eax, [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 ebp ecx esi edi
mov eax, ERROR_FILE_NOT_FOUND
or ebx, -1
ret
.done:
add esp, 262*2+4+8
pop ebp
mov ebx, [edx+4]
xor eax, eax
dec ecx
js @f
mov al, ERROR_END_OF_FILE
@@:
pop ecx esi edi
ret
; \end{diamond}
View Git Blame Copy Permalink