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kolibrios/kernel/trunk/fs/fat12.inc

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Kolibri 5 initial checkout git-svn-id: svn://kolibrios.org@1 a494cfbc-eb01-0410-851d-a64ba20cac60
2005-10-06 19:56:22 +02:00
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; FAT12.INC ;;
;; (C) 2005 Mario79, License: GPL ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
n_sector dd 0 ; temporary save for sector value
flp_status dd 0
clust_tmp_flp dd 0 ; used by analyze_directory and analyze_directory_to_write
path_pointer_flp dd 0
pointer_file_name_flp dd 0
save_root_flag db 0
save_flag db 0
root_read db 0 ; 0-necessary to load root, 1-not to load root
flp_fat db 0 ; 0-necessary to load fat, 1-not to load fat
flp_number db 0 ; 1- Floppy A, 2-Floppy B
old_track db 0 ; old value track
flp_label rb 15 ; Label and ID of inserted floppy disk
reserve_flp:
cli
cmp [flp_status],0
je reserve_flp_ok
sti
call change_task
jmp reserve_flp
reserve_flp_ok:
push eax
mov eax,[0x3000]
shl eax,5
mov eax,[eax+0x3000+4]
mov [flp_status],eax
pop eax
sti
ret
floppy_free_space:
;---------------------------------------------
;
; returns free space in edi
;
;---------------------------------------------
push eax ebx ecx
call read_flp_fat
cmp [FDC_Status],0
jne fdc_status_error_2
mov eax,0x282000
xor edi,edi
mov ecx,2847 ;1448000/512
rdfs1_1:
mov ebx,[eax]
and ebx,4095
cmp ebx,0
jne rdfs2_1
add edi,512
rdfs2_1:
add eax,2
loop rdfs1_1
fdc_status_error_2:
pop ecx ebx eax
ret
floppy_fileread:
;----------------------------------------------------------------
;
; fileread - sys floppy
;
; eax points to filename 11 chars - for root directory
; ebx first wanted block ; 1+ ; if 0 then set to 1
; ecx number of blocks to read ; 1+ ; if 0 then set to 1
; edx mem location to return data
; esi length of filename 12*X
; edi pointer to path /fd/1/...... - for all files in nested directories
;
; ret ebx = size or 0xffffffff file not found
; eax = 0 ok read or other = errormsg
; 10 = access denied
;--------------------------------------------------------------
mov [save_flag],0
mov [path_pointer_flp],edi
cmp esi,0 ; return ramdisk root
jne fr_noroot_1
cmp ebx,224/16
jbe fr_do_1
mov eax,5
mov ebx,0
mov [flp_status],0
ret
fr_do_1:
push ebx ecx edx
call read_flp_root
pop edx ecx ebx
cmp [FDC_Status],0
jne fdc_status_error_1
mov edi,edx
dec ebx
shl ebx,9
mov esi,0x8000
add esi,ebx
shl ecx,9
cld
rep movsb
mov eax,0 ; ok read
mov ebx,0
mov [flp_status],0
ret
fdc_status_error_1:
mov [flp_status],0
mov eax,10
mov ebx,-1
ret
fr_noroot_1:
sub esp,32
call expand_filename
frfloppy_1:
cmp ebx,0
jne frfl5_1
mov ebx,1
frfl5_1:
cmp ecx,0
jne frfl6_1
mov ecx,1
frfl6_1:
dec ebx
push eax
push eax ebx ecx edx esi edi
call read_flp_fat
cmp [FDC_Status],0
jne fdc_status_error_3_1
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],1 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
call SeekTrack
mov dh,14
l.20_1:
call ReadSectWithRetr
cmp [FDC_Status],0
jne fdc_status_error_3_1
mov dl,16
mov edi,0xD000
inc [FDD_Sector]
l.21_1:
mov esi,eax ;Name of file we want
mov ecx,11
cld
rep cmpsb ;Found the file?
je fifound_1 ;Yes
add ecx,21
add edi, ecx ;Advance to next entry
dec dl
cmp dl,0
jne l.21_1
dec dh
cmp dh,0
jne l.20_1
fdc_status_error_3:
mov eax,5 ; file not found ?
mov ebx,-1
add esp,32+28
mov [flp_status],0
ret
fdc_status_error_3_2:
cmp [FDC_Status],0
je fdc_status_error_3
fdc_status_error_3_1:
add esp,32+28
jmp fdc_status_error_1
fifound_1:
mov eax,[path_pointer_flp]
cmp [eax+36],byte 0
je fifound_2
add edi,0xf
mov eax,[edi]
and eax,65535
mov ebx,[path_pointer_flp]
add ebx,36
call get_cluster_of_a_path_flp
jc fdc_status_error_3_2
mov ebx,[ebx-11+28] ;file size
mov [esp+20],ebx
mov [esp+24],ebx
jmp fifound_3
fifound_2:
mov ebx,[edi-11+28] ;file size
mov [esp+20],ebx
mov [esp+24],ebx
add edi,0xf
mov eax,[edi]
fifound_3:
and eax,65535
mov [n_sector],eax ;eax=cluster
frnew_1:
add eax,31 ;bootsector+2*fat+filenames
cmp [esp+16],dword 0 ; wanted cluster ?
jne frfl7_1
call read_chs_sector
cmp [FDC_Status],0
jne fdc_status_error_5
mov edi,[esp+8]
call give_back_application_data_1
add [esp+8],dword 512
dec dword [esp+12] ; last wanted cluster ?
cmp [esp+12],dword 0
je frnoread_1
jmp frfl8_1
frfl7_1:
dec dword [esp+16]
frfl8_1:
mov edi,[n_sector]
shl edi,1 ;find next cluster from FAT
add edi,0x282000
mov eax,[edi]
and eax,4095
mov edi,eax
mov [n_sector],edi
cmp edi,4095 ;eof - cluster
jz frnoread2_1
cmp [esp+24],dword 512 ;eof - size
jb frnoread_1
sub [esp+24],dword 512
jmp frnew_1
read_chs_sector:
call calculate_chs
call ReadSectWithRetr
ret
frnoread2_1:
cmp [esp+16],dword 0 ; eof without read ?
je frnoread_1
mov [fdc_irq_func],fdc_null
pop edi esi edx ecx
add esp,4
pop ebx ; ebx <- eax : size of file
add esp,36
mov eax,6 ; end of file
mov [flp_status],0
ret
frnoread_1:
pop edi esi edx ecx
add esp,4
pop ebx ; ebx <- eax : size of file
add esp,36
mov eax,0
mov [flp_status],0
ret
fdc_status_error_5:
pop edi esi edx ecx
add esp,4
pop ebx ; ebx <- eax : size of file
add esp,36
jmp fdc_status_error_1
read_flp_root:
pusha
call check_label
cmp [FDC_Status],0
jne unnecessary_root_read
cmp [root_read],1
je unnecessary_root_read
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],1 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov edi,0x8000
call SeekTrack
read_flp_root_1:
call ReadSectWithRetr
cmp [FDC_Status],0
jne unnecessary_root_read
push edi
call give_back_application_data_1
pop edi
add edi,512
inc [FDD_Sector]
cmp [FDD_Sector],16
jne read_flp_root_1
mov [root_read],1
unnecessary_root_read:
popa
ret
read_flp_fat:
pusha
call check_label
cmp [FDC_Status],0
jne unnecessary_flp_fat
cmp [flp_fat],1
je unnecessary_flp_fat
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov edi,0x8000
call SeekTrack
read_flp_fat_1:
call ReadSectWithRetr
cmp [FDC_Status],0
jne unnecessary_flp_fat
push edi
call give_back_application_data_1
pop edi
add edi,512
inc [FDD_Sector]
cmp [FDD_Sector],19
jne read_flp_fat_1
mov [FDD_Sector],1
mov [FDD_Head],1
call ReadSectWithRetr
cmp [FDC_Status],0
jne unnecessary_flp_fat
call give_back_application_data_1
call calculatefatchain_flp
mov [root_read],0
mov [flp_fat],1
unnecessary_flp_fat:
popa
ret
calculatefatchain_flp:
pushad
mov esi,0x8000
mov edi,0x282000
fcnew_1:
mov eax,dword [esi]
mov ebx,dword [esi+4]
mov ecx,dword [esi+8]
mov edx,ecx
shr edx,4 ;8 ok
shr dx,4 ;7 ok
xor ch,ch
shld ecx,ebx,20 ;6 ok
shr cx,4 ;5 ok
shld ebx,eax,12
and ebx,0x0fffffff ;4 ok
shr bx,4 ;3 ok
shl eax,4
and eax,0x0fffffff ;2 ok
shr ax,4 ;1 ok
mov dword [edi],eax
add edi,4
mov dword [edi],ebx
add edi,4
mov dword [edi],ecx
add edi,4
mov dword [edi],edx
add edi,4
add esi,12
cmp edi,0x282000+2856*2 ;2849 clusters
jnz fcnew_1
popad
ret
check_label:
pushad
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],1 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
call SetUserInterrupts
call FDDMotorON
call RecalibrateFDD
cmp [FDC_Status],0
jne fdc_status_error
call SeekTrack
cmp [FDC_Status],0
jne fdc_status_error
call ReadSectWithRetr
cmp [FDC_Status],0
jne fdc_status_error
mov esi,flp_label
mov edi,0xD000+39
mov ecx,15
cld
rep cmpsb
je same_label
mov [root_read],0
mov [flp_fat],0
same_label:
mov esi,0xD000+39
mov edi,flp_label
mov ecx,15
cld
rep movsb
popad
ret
fdc_status_error:
popad
ret
save_flp_root:
pusha
call check_label
cmp [FDC_Status],0
jne unnecessary_root_save
cmp [root_read],0
je unnecessary_root_save
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],1 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov esi,0x8000
call SeekTrack
save_flp_root_1:
push esi
call take_data_from_application_1
pop esi
add esi,512
call WriteSectWithRetr
cmp [FDC_Status],0
jne unnecessary_root_save
inc [FDD_Sector]
cmp [FDD_Sector],16
jne save_flp_root_1
unnecessary_root_save:
mov [fdc_irq_func],fdc_null
popa
ret
save_flp_fat:
pusha
call check_label
cmp [FDC_Status],0
jne unnecessary_flp_fat_save
cmp [flp_fat],0
je unnecessary_flp_fat_save
call restorefatchain_flp
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov esi,0x8000
call SeekTrack
save_flp_fat_1:
push esi
call take_data_from_application_1
pop esi
add esi,512
call WriteSectWithRetr
cmp [FDC_Status],0
jne unnecessary_flp_fat_save
inc [FDD_Sector]
cmp [FDD_Sector],19
jne save_flp_fat_1
mov [FDD_Sector],1
mov [FDD_Head],1
call take_data_from_application_1
call WriteSectWithRetr
cmp [FDC_Status],0
jne unnecessary_flp_fat_save
mov [root_read],0
unnecessary_flp_fat_save:
mov [fdc_irq_func],fdc_null
popa
ret
restorefatchain_flp: ; restore fat chain
pushad
mov esi,0x282000
mov edi,0x8000
fcnew2_1:
mov eax,dword [esi]
mov ebx,dword [esi+4]
shl ax,4
shl eax,4
shl bx,4
shr ebx,4
shrd eax,ebx,8
shr ebx,8
mov dword [edi],eax
add edi,4
mov word [edi],bx
add edi,2
add esi,8
cmp edi,0x8000+0x1200 ;4274 bytes - all used FAT
jb fcnew2_1
mov esi,0x8000 ; duplicate fat chain
mov edi,0x8000+0x1200
mov ecx,0x1200/4
cld
rep movsd
popad
ret
floppy_filedelete:
;--------------------------------------------
;
; filedelete - sys floppy
; in:
; eax - filename 11 chars - for root directory
; edi pointer to path /fd/1/...... - for all files in nested directories
;
; out:
; eax - 0 = successful, 1 = file not found, 10 = access denied
;
;--------------------------------------------
mov [path_pointer_flp],edi
mov [save_flag],0
mov ebp,1 ; file not found as default
filedelete_newtry_1:
sub esp,32
call expand_filename
push eax ebx ecx edx esi edi
call read_flp_fat
cmp [FDC_Status],0
jne frnoreadd_1
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],1 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
call SeekTrack
mov dh,14
l.20_2:
call ReadSectWithRetr
cmp [FDC_Status],0
jne fdc_status_error_4
mov dl,16
mov edi,0xD000
inc [FDD_Sector]
l.21_2:
mov esi,eax ;Name of file we want
mov ecx,11
cld
rep cmpsb ;Found the file?
je fifoundd_1 ;Yes
add ecx,21
add edi, ecx ;Advance to next entry
dec dl
cmp dl,0
jne l.21_2
dec dh
cmp dh,0
jne l.20_2
jmp frnoreadd_1
fdc_status_error_4:
pop edi esi edx ecx ebx eax
add esp,32
jmp fdc_status_error_1
fifoundd_1:
mov eax,[path_pointer_flp]
cmp [eax+36],byte 0
je fifoundd_2
add edi,0xf
mov eax,[edi]
and eax,65535
mov ebx,[path_pointer_flp]
add ebx,36
call get_cluster_of_a_path_flp
jc frnoreadd_1_1
mov edi,ebx
add edi,11
jmp fifoundd_2_1
fifoundd_2:
dec [FDD_Sector]
fifoundd_2_1:
mov [edi-11],byte 0xE5 ;mark filename deleted
add edi,0xf
mov eax,[edi]
and eax,65535
mov edi,eax ;edi = cluster
frnewd_1:
shl edi,1 ;find next cluster from FAT
add edi,0x282000
mov eax,[edi]
mov [edi],word 0x0 ;clear fat chain cluster
and eax,4095
mov edi,eax
cmp edi,dword 4095 ;last cluster ?
jz frnoreadd2_1
jmp frnewd_1
frnoreadd2_1:
call WriteSectWithRetr
cmp [FDC_Status],0
jne fdc_status_error_4
call save_flp_fat
cmp [FDC_Status],0
jne fdc_status_error_4
; pop edi esi edx ecx ebx eax
; add esp,32
mov ebp,0 ; file found
; jmp filedelete_newtry_1
jmp frnoreadd_1
frnoreadd_1_1:
cmp [FDC_Status],0
jne fdc_status_error_4
frnoreadd_1:
pop edi esi edx ecx ebx eax
add esp,32
mov eax,ebp
ret
floppy_filesave:
;----------------------------------------------------------
;
; filesave - sys floppy
;
; eax ; pointer to file name 11 chars - for root directory
; ebx ; buffer
; ecx ; count to write in bytes
; edx ; 0 create new , 1 append
; edi pointer to path /fd/1/...... - for all files in nested directories
;
; output : eax = 0 - ok
; 5 - file not found / directory not found
; 8 - disk full
; 10 - access denied
;-----------------------------------------------------------
mov [path_pointer_flp],edi
sub esp,32
call expand_filename
cmp edx,0
jnz fsdel_1
pusha
call floppy_filedelete
cmp [FDC_Status],0
jne fdc_status_error_6
popa
mov [save_flag],1
fsdel_1:
call floppy_free_space
cmp [FDC_Status],0
jne fdc_status_error_6
cmp ecx,edi
jb rd_do_save_1
add esp,32
mov eax,8 ; not enough free space
mov [flp_status],0
ret
fdc_status_error_6:
popa
add esp,32
jmp fdc_status_error_1
rd_do_save_1:
push eax ebx ecx edx esi edi
call read_flp_fat
cmp [FDC_Status],0
jne fdc_status_error_7
push eax
mov eax,[path_pointer_flp]
cmp [eax+36],byte 0
jne fifoundds_2
pop eax
mov [save_root_flag],1
call read_flp_root
cmp [FDC_Status],0
jne fdc_status_error_7
mov edi,0x8000 ;Point at directory
mov edx,224 +1
; find an empty spot for filename in the root dir
l20ds_1:
sub edx,1
cmp edx,0
jnz l21ds_1
jmp frnoreadds_1
l21ds_1:
cmp [edi],byte 0xE5
jz fifoundds_1
cmp [edi],byte 0x0
jz fifoundds_1
add edi,32 ; Advance to next entry
jmp l20ds_1
fifoundds_2:
pop eax
mov [save_root_flag],0
mov [FDD_Track],0 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Head],1 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
mov [FDD_Sector],2 ; <EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
call SeekTrack
mov dh,14
l.20_3:
call ReadSectWithRetr
cmp [FDC_Status],0
jne fdc_status_error_7
mov dl,16
mov edi,0xD000
inc [FDD_Sector]
l.21_3:
mov esi,eax ;Name of file we want
mov ecx,11
cld
rep cmpsb ;Found the file?
je fifoundds_3 ;Yes
add ecx,21
add edi, ecx ;Advance to next entry
dec dl
cmp dl,0
jne l.21_3
dec dh
cmp dh,0
jne l.20_3
fdc_status_error_8:
pop edi esi edx ecx ebx eax
mov eax,5 ; file not found ?
mov ebx,-1
add esp,32
mov [flp_status],0
ret
fifoundds_3:
add edi,0xf
mov eax,[edi]
and eax,65535
mov ebx,[path_pointer_flp]
add ebx,36
call get_cluster_of_a_path_flp
jc fdc_status_error_7_1
found_directory_for_writing_flp:
call analyze_directory_to_write_flp
jc fdc_status_error_7_1
mov edi,ebx
fifoundds_1:
push edi ; move the filename to root dir
mov esi,[esp+4+20]
cmp [save_root_flag],0
jne fifoundds_4
mov esi,[pointer_file_name_flp]
fifoundds_4:
mov ecx,11
cld
rep movsb
pop edi
mov edx,edi
add edx,11+0xf ; edx <- cluster save position
mov ebx,[esp+12] ; save file size
mov [edi+28],ebx
mov [edi+11],byte 0x20 ; attribute
call get_date_for_file ; from FAT32.INC
mov [edi+24],ax ; date
mov [edi+18],ax ; date
call get_time_for_file ; from FAT32.INC
mov [edi+22],ax ; time
xor ax,ax
mov [edi+20],ax
mov ebx,1 ; first cluster
cmp [save_root_flag],0
jne frnewds_1
call frnewds_2
pusha
call WriteSectWithRetr
popa
cmp [FDC_Status],0
jne fdc_status_error_7
jmp frnewds_3
frnewds_1:
call frnewds_2
frnewds_3:
pusha ; move save to floppy cluster
add ebx,31
mov eax,ebx
mov esi,[esp+32+16]
call take_data_from_application_1
call save_chs_sector
cmp [FDC_Status],0
jne fdc_status_error_7
popa
mov eax,[esp+12]
cmp eax,512
jb flnsa_1
sub eax,512
mov [esp+12],eax
mov eax,[esp+16]
add eax,512
mov [esp+16],eax
jmp frnewds_1
frnewds_2:
add ebx,1
mov edi,ebx ; find free cluster in FAT
shl edi,1
add edi,0x282000
mov eax,[edi]
and eax,4095
cmp eax,0x0
jnz frnewds_2
mov [edx],bx ; save next cluster pos. to prev cl.
mov edx,edi ; next save pos abs mem add
ret
flnsa_1:
mov [edi],word 4095 ; mark end of file - last cluster
cmp [save_root_flag],1
jne flnsa_2
call save_flp_root
cmp [FDC_Status],0
jne fdc_status_error_7
flnsa_2:
call save_flp_fat
cmp [FDC_Status],0
jne fdc_status_error_7
frnoreadds_1:
pop edi esi edx ecx ebx eax
add esp,32
mov eax,0
mov [flp_status],0
ret
fdc_status_error_7_1:
cmp [FDC_Status],0
je fdc_status_error_8
fdc_status_error_7:
pop edi esi edx ecx ebx eax
add esp,32
jmp fdc_status_error_1
save_chs_sector:
call calculate_chs
call WriteSectWithRetr
ret
calculate_chs:
mov bl,[FDD_Track]
mov [old_track],bl
mov ebx,18
xor edx,edx
div ebx
inc edx
mov [FDD_Sector],dl
xor edx,edx
mov ebx,2
div ebx
mov [FDD_Track],al
mov [FDD_Head],0
cmp edx,0
je no_head_2
inc [FDD_Head]
no_head_2:
mov dl,[old_track]
cmp dl,[FDD_Track]
je no_seek_track_1
call SeekTrack
no_seek_track_1:
ret
get_cluster_of_a_path_flp:
;---------------------------------------------------------
; 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 edx
mov edx,ebx
search_end_of_path_flp:
cmp [save_flag],0
jne search_end_of_path_flp_1
cmp byte [edx],0
je found_end_of_path_flp
jmp search_end_of_path_flp_2
search_end_of_path_flp_1:
cmp byte [edx+12],0
je found_end_of_path_flp
search_end_of_path_flp_2:
inc edx ; '/'
call analyze_directory_flp
jc directory_not_found_flp
mov eax,[ebx+20-2] ; read the HIGH 16bit cluster field
mov ax,[ebx+26] ; read the LOW 16bit cluster field
and eax,0xfff ;[fatMASK]
add edx,11 ; 8+3 (name+extension)
jmp search_end_of_path_flp
found_end_of_path_flp:
inc edx
mov [pointer_file_name_flp],edx
pop edx
clc ; no errors
ret
directory_not_found_flp:
pop edx
stc ; errors occour
ret
analyze_directory_flp:
;--------------------------------
; 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,EDI,EDI not changed
; IF CARRY=1
;--------------------------------
push ebx ;[esp+16]
push ecx
push edx
push esi
push edi
adr56_flp:
mov [clust_tmp_flp],eax
add eax,31
pusha
call read_chs_sector
popa
cmp [FDC_Status],0
jne not_found_file_analyze_flp
mov ecx,512/32
mov ebx,0xD000
adr1_analyze_flp:
mov esi,edx ;[esp+16]
mov edi,ebx
cld
push ecx
mov ecx,11
rep cmpsb
pop ecx
je found_file_analyze_flp
add ebx,32
loop adr1_analyze_flp
mov eax,[clust_tmp_flp]
shl eax,1 ;find next cluster from FAT
add eax,0x282000
mov eax,[eax]
and eax,4095
cmp eax,0x0ff8
jb adr56_flp
not_found_file_analyze_flp:
pop edi
pop esi
pop edx
pop ecx
add esp,4
stc ;file not found
ret
found_file_analyze_flp:
pop edi
pop esi
pop edx
pop ecx
add esp,4
clc ;file found
ret
analyze_directory_to_write_flp:
;--------------------------------
; input : EAX = first cluster of the directory
; output : IF CARRY=0 EAX = sector where the file is found
; EBX = pointer in buffer
; [buffer .. buffer+511]
; ECX,EDX,EDI,EDI not changed
; IF CARRY=1
;--------------------------------
push ecx
push edx
push esi
adr561:
mov [clust_tmp_flp],eax
add eax,31
pusha
call read_chs_sector
popa
cmp [FDC_Status],0
jne error_found_file_analyze1
mov ecx,512/32
mov ebx,0xD000
adr1_analyze1:
cmp byte [ebx],0x00
je found_file_analyze1
cmp byte [ebx],0xe5
je found_file_analyze1
avanti:
add ebx,32
loop adr1_analyze1
mov eax,[clust_tmp_flp]
shl eax,1 ;find next cluster from FAT
add eax,0x282000
mov eax,[eax]
and eax,4095
cmp eax,0x0ff8
jb adr561
call get_free_FAT ;this block of code add a new cluster
;for the directory because the directory
;is full
mov [edi],word 0x0fff
mov eax,[clust_tmp_flp]
shl eax,1 ;find next cluster from FAT
add eax,0x282000
sub edi,0x282000
mov [eax],di
pusha
mov ecx,512/4
xor eax,eax
mov edi,0xD000
cld
rep stosd
popa
mov eax,edi
add eax,31
pusha
call save_chs_sector
popa
cmp [FDC_Status],0
jne error_found_file_analyze1
mov ebx,0xD000
found_file_analyze1:
pop esi
pop edx
pop ecx
clc ;file found
ret
error_found_file_analyze1:
pop esi
pop edx
pop ecx
stc
ret
get_free_FAT_flp:
;------------------------------------------
; input : EAX = # cluster for start the searching
; output : EAX = # first cluster found free
;-------------------------------------------
push ebx
mov ebx,1
check_new_flp:
add ebx,1
mov edi,ebx ; find free cluster in FAT
shl edi,1
add edi,0x282000
mov eax,[edi]
and eax,4095
cmp eax,0x0
jnz check_new_flp
pop ebx
ret
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