rom/dos/flush.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <aros/debug.h>
   7
   8 #include <dos/dosextens.h>
   9 #include <proto/dos.h>
  10 #include "dos_intern.h"
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <proto/dos.h>
  16
  17         AROS_LH1(LONG, Flush,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(BPTR, file, D1),
  21
  22 /*  LOCATION */
  23         struct DosLibrary *, DOSBase, 60, Dos)
  24
  25 /*  FUNCTION
  26         Flushes any pending writes on the file. If the file was used
  27         for input and there is still some data to read it tries to
  28         seek back to the expected position.
  29
  30     INPUTS
  31         file - filehandle
  32
  33     RESULT
  34         != 0 on success, 0 on error. IoErr() gives additional information
  35         in that case.
  36
  37     NOTES
  38
  39     EXAMPLE
  40
  41     BUGS
  42
  43     SEE ALSO
  44
  45     INTERNALS
  46
  47 *****************************************************************************/
  48 {
  49     AROS_LIBFUNC_INIT
  50
  51     /* Get pointer to filehandle. */
  52     struct FileHandle *fh = (struct FileHandle *)BADDR(file);
  53
  54     if (!fh)
  55         return DOSTRUE;
  56
  57     /* The file must be in write mode. */
  58     if( fh->fh_Flags & FHF_WRITE )
  59     {
  60         /* Handle append mode. */
  61         if( fh->fh_Flags & FHF_APPEND )
  62         {
  63             InternalSeek( fh, 0, OFFSET_END, DOSBase );
  64         }
  65
  66         return InternalFlush( fh, DOSBase );
  67     }
  68     else if( fh->fh_Pos < fh->fh_End )
  69     {
  70         int offset = fh->fh_Pos - fh->fh_End;
  71
  72         fh->fh_Pos = fh->fh_End = 0;
  73
  74         /* Read mode. Try to seek back to the current position. */
  75         if( InternalSeek( fh, offset, OFFSET_CURRENT, DOSBase ) < 0 )
  76         {
  77             return FALSE;
  78         }
  79     }
  80
  81     return TRUE;
  82
  83     AROS_LIBFUNC_EXIT
  84 } /* Flush */