rom/dos/internalseek.c

   1 /*
   2     Copyright © 2002, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #undef SDEBUG
   7 #undef DEBUG
   8 #define DEBUG 0
   9 #include <aros/debug.h>
  10
  11 #include <proto/dos.h>
  12 #include "dos_intern.h"
  13
  14 LONG InternalSeek
  15 (
  16     struct FileHandle *fh,
  17     LONG               position,
  18     LONG               mode,
  19     struct DosLibrary *DOSBase
  20 )
  21 {
  22     AROS_LIBBASE_EXT_DECL( struct DosLibrary *, DOSBase )
  23
  24     /* Get pointer to I/O request. Use stackspace for now. */
  25     struct IOFileSys iofs;
  26
  27     /* Make sure the input parameters are sane. */
  28     ASSERT_VALID_PTR( fh );
  29     ASSERT
  30     (
  31            mode == OFFSET_BEGINNING
  32         || mode == OFFSET_END
  33         || mode == OFFSET_CURRENT
  34     );
  35
  36     /* Prepare I/O request. */
  37     InitIOFS( &iofs, FSA_SEEK, DOSBase );
  38
  39     iofs.IOFS.io_Device = fh->fh_Device;
  40     iofs.IOFS.io_Unit   = fh->fh_Unit;
  41
  42     iofs.io_Union.io_SEEK.io_Offset   = (QUAD)position;
  43     iofs.io_Union.io_SEEK.io_SeekMode = mode;
  44
  45     /* Send the request. */
  46     DosDoIO( &iofs.IOFS );
  47
  48     if( iofs.io_DosError )
  49     {
  50         SetIoErr( iofs.io_DosError );
  51         return -1;
  52     }
  53     else
  54         return (LONG) iofs.io_Union.io_SEEK.io_Offset;
  55 }