Subversion Repositories Kolibri OS

align 4

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

uglobal

  dir_entry:           times 32 db 0

  startpath:           times 255 db 0

  fat_change           db 0       ; 1=fat has changed

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   [fs_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

    call  set_FAT

    cmp  [hd_error],0

    jne  adw_not_found_1

    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

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

    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     [fs_type], 16

        jz      fat_ok_for_writing

        cmp     [fs_type], 32

        jz      fat_ok_for_writing

        push    ERROR_UNKNOWN_FS

        pop     eax

        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

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     [fs_type], 16

        jz      file_del_fat_ok

        cmp     [fs_type], 32

        jz      file_del_fat_ok

        push    ERROR_UNKNOWN_FS

        pop     eax

        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?

    jnz   delete_no_access

  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

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

    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