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        xchg    edi, [esp+4]

        mov     edi, [esp+4]

;----------------------------------------------------------------

;

;  fs_FloppySetFileEnd - set end of file on floppy

;

;  esi  points to filename

;  ebx  points to 64-bit number = new file size

;  ecx  ignored (reserved)

;  edx  ignored (reserved)

;

;  ret eax = 0 ok or other = errormsg

;

;--------------------------------------------------------------

fs_FloppySetFileEnd:

        call    read_flp_fat

        cmp     [FDC_Status], 0

        jnz     ret11

        cmp     byte [esi], 0

        jnz     @f

.access_denied:

        push    ERROR_ACCESS_DENIED

        jmp     .ret

@@:

        push    edi

        call    fd_find_lfn

        jnc     @f

        pop     edi

        push    ERROR_FILE_NOT_FOUND

.ret:

        pop     eax

        jmp     .doret

@@:

; must not be directory

        test    byte [edi+11], 10h

        jz      @f

        pop     edi

        jmp     .access_denied

@@:

; file size must not exceed 4 Gb

        cmp     dword [ebx+4], 0

        jz      @f

        pop     edi

        push    ERROR_END_OF_FILE

        jmp     .ret

@@:

        push    eax

; set file modification date/time to current

        call    fat_update_datetime

        mov     eax, [ebx]

        cmp     eax, [edi+28]

        jb      .truncate

        ja      .expand

        pop     eax

        pushad

        call    save_chs_sector

        popad

        pop     edi

        xor     eax, eax

        cmp     [FDC_Status], 0

        jz      @f

        mov     al, 11

@@:

.doret:

        mov     [fdc_irq_func], fdc_null

        ret

.expand:

        push    ecx

        push    dword [edi+28]  ; save old size

        mov     ecx, eax

        call    floppy_extend_file

        push    eax     ; return code

        jnc     .expand_ok

        cmp     al, ERROR_DISK_FULL

        jz      .disk_full

        pop     eax ecx ecx edi edi

        jmp     .doret

.device_err:

        pop     eax

.device_err2:

        pop     ecx ecx eax edi

        push    11

        jmp     .ret

.disk_full:

.expand_ok:

; save directory & FAT

        mov     eax, [edi+28]

        xchg    eax, [esp+12]

        movzx   edi, word [edi+26]

        pusha

        call    save_chs_sector

        popa

        cmp     [FDC_Status], 0

        jnz     .device_err

        call    save_flp_fat

        cmp     [FDC_Status], 0

        jnz     .device_err

        call    SetUserInterrupts

; now zero new data

; edi = current cluster, [esp+12]=new size, [esp+4]=old size, [esp]=return code

.zero_loop:

        sub     dword [esp+4], 0x200

        jae     .next_cluster

        cmp     dword [esp+4], -0x200

        jz      .noread

        lea     eax, [edi+31]

        pusha

        call    read_chs_sector

        popa

        cmp     [FDC_Status], 0

        jnz     .err_next

.noread:

        mov     ecx, [esp+4]

        neg     ecx

        push    edi

        mov     edi, 0xD000+0x200

        add     edi, [esp+8]

        xor     eax, eax

        mov     [esp+8], eax

        rep     stosb

        pop     edi

        lea     eax, [edi+31]

        pusha

        call    save_chs_sector

        popa

        cmp     [FDC_Status], 0

        jz      .next_cluster

.err_next:

        mov     byte [esp], 11

.next_cluster:

        sub     dword [esp+12], 0x200

        jbe     .expand_done

        movzx   edi, word [0x282000+edi*2]

        jmp     .zero_loop

.expand_done:

        pop     eax ecx ecx edi edi

        jmp     .doret

.truncate:

        mov     [edi+28], eax

        push    ecx

        movzx   ecx, word [edi+26]

        test    eax, eax

        jz      .zero_size

; find new last sector

@@:

        sub     eax, 0x200

        jbe     @f

        movzx   ecx, word [0x282000+ecx*2]

        jmp     @b

@@:

; we will zero data at the end of last sector - remember it

        push    ecx

; terminate FAT chain

        lea     ecx, [0x282000+ecx+ecx]

        push    dword [ecx]

        mov     word [ecx], 0xFFF

        pop     ecx

        and     ecx, 0xFFF

        jmp     .delete

.zero_size:

        and     word [edi+26], 0

        push    0

.delete:

; delete FAT chain starting with ecx

; mark all clusters as free

        cmp     ecx, 0xFF8

        jae     .deleted

        lea     ecx, [0x282000+ecx+ecx]

        push    dword [ecx]

        and     word [ecx], 0

        pop     ecx

        and     ecx, 0xFFF

        jmp     .delete

.deleted:

        mov     edi, [edi+28]

; save directory & FAT

        mov     eax, [esp+8]

        pusha

        call    save_chs_sector

        popa

        cmp     [FDC_Status], 0

        jnz     .device_err2

        call    save_flp_fat

        cmp     [FDC_Status], 0

        jnz     .device_err2

; zero last sector, ignore errors

        pop     eax

        add     eax, 31

        and     edi, 0x1FF

        jz      .truncate_done

        call    SetUserInterrupts

        pusha

        call    read_chs_sector

        popa

        add     edi, 0xD000

        mov     ecx, 0xD000+0x200

        sub     ecx, edi

        push    eax

        xor     eax, eax

        rep     stosb

        pop     eax

        pusha

        call    save_chs_sector

        popa

.truncate_done:

        pop     ecx eax edi

        xor     eax, eax

        jmp     .doret