rom/dos/addbuffers.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Add or remove cache memory from a filesystem.
   6     Lang: English
   7 */
   8 #include <proto/exec.h>
   9 #include <dos/dosextens.h>
  10 #include "dos_intern.h"
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <proto/dos.h>
  16
  17         AROS_LH2(LONG, AddBuffers,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(CONST_STRPTR, devicename, D1),
  21         AROS_LHA(LONG,         numbuffers, D2),
  22
  23 /*  LOCATION */
  24         struct DosLibrary *, DOSBase, 122, Dos)
  25
  26 /*  FUNCTION
  27         Add or remove cache memory from a filesystem.
  28
  29     INPUTS
  30         devicename  --  NUL terminated dos device name.
  31         numbuffers  --  Number of buffers to add. May be negative.
  32
  33     RESULT
  34         != 0 on success (IoErr() gives the actual number of buffers),
  35         0 else (IoErr() gives the error code).
  36
  37     NOTES
  38
  39     EXAMPLE
  40
  41     BUGS
  42
  43     SEE ALSO
  44
  45     INTERNALS
  46
  47     The error value in case of a filesystem error will be reported in
  48     the io_MORE_CACHE.io_NumBuffers field.
  49
  50 *****************************************************************************/
  51
  52 {
  53     AROS_LIBFUNC_INIT
  54
  55     struct DevProc *dvp;
  56     LONG ret;
  57
  58     /* get the device */
  59     if ((dvp = GetDeviceProc(devicename, NULL)) == NULL)
  60         return DOSFALSE;
  61
  62     /* we're only interested in real devices */
  63     if (dvp->dvp_DevNode == NULL ||
  64         dvp->dvp_DevNode->dol_Type != DLT_DEVICE) {
  65         FreeDeviceProc(dvp);
  66         SetIoErr(ERROR_DEVICE_NOT_MOUNTED);
  67         return DOSFALSE;
  68     }
  69
  70     ret = dopacket1(DOSBase, NULL, dvp->dvp_Port, ACTION_MORE_CACHE, numbuffers);
  71
  72     FreeDeviceProc(dvp);
  73
  74     return ret;
  75
  76     AROS_LIBFUNC_EXIT
  77 } /* AddBuffers */