rom/dos/setfilesize.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Change the size of a file.
   6     Lang: english
   7 */
   8 #include <proto/exec.h>
   9 #include <dos/dosextens.h>
  10 #include <dos/filesystem.h>
  11 #include "dos_intern.h"
  12
  13 /*****************************************************************************
  14
  15     NAME */
  16 #include <proto/dos.h>
  17
  18         AROS_LH3(LONG, SetFileSize,
  19
  20 /*  SYNOPSIS */
  21         AROS_LHA(BPTR, file,   D1),
  22         AROS_LHA(LONG, offset, D2),
  23         AROS_LHA(LONG, mode,   D3),
  24
  25 /*  LOCATION */
  26         struct DosLibrary *, DOSBase, 76, Dos)
  27
  28 /*  FUNCTION
  29         Change the size of a file.
  30
  31     INPUTS
  32         file   - filehandle
  33         offset - relative size
  34         mode   - OFFSET_BEGINNING, OFFSET_CURRENT or OFFSET_END
  35
  36     RESULT
  37         New size of the file or -1 in case of an error.
  38         IoErr() gives additional information in that case.
  39
  40     NOTES
  41
  42     EXAMPLE
  43
  44     BUGS
  45
  46     SEE ALSO
  47
  48     INTERNALS
  49
  50 *****************************************************************************/
  51 {
  52     AROS_LIBFUNC_INIT
  53
  54     /* Get pointer to filehandle */
  55     struct FileHandle *fh = (struct FileHandle *)BADDR(file);
  56
  57     /* Get pointer to I/O request. Use stackspace for now. */
  58     struct IOFileSys iofs;
  59
  60     /* Prepare I/O request. */
  61     InitIOFS(&iofs, FSA_SET_FILE_SIZE, DOSBase);
  62
  63     iofs.IOFS.io_Device = fh->fh_Device;
  64     iofs.IOFS.io_Unit   = fh->fh_Unit;
  65
  66     iofs.io_Union.io_SET_FILE_SIZE.io_Offset   = (QUAD)offset;
  67     iofs.io_Union.io_SET_FILE_SIZE.io_SeekMode = mode;
  68
  69     /* Send the request. */
  70     DosDoIO(&iofs.IOFS);
  71
  72     SetIoErr(iofs.io_DosError);
  73
  74     if(iofs.io_DosError != 0)
  75         return -1;
  76     else
  77         return (LONG)iofs.io_Union.io_SET_FILE_SIZE.io_Offset;
  78
  79     AROS_LIBFUNC_EXIT
  80 } /* SetFileSize */