rom/dos/samelock.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6     Lang: english
   7 */
   8 #include "dos_intern.h"
   9
  10 /*****************************************************************************
  11
  12     NAME */
  13 #include <proto/dos.h>
  14
  15         AROS_LH2(LONG, SameLock,
  16
  17 /*  SYNOPSIS */
  18         AROS_LHA(BPTR, lock1, D1),
  19         AROS_LHA(BPTR, lock2, D2),
  20
  21 /*  LOCATION */
  22         struct DosLibrary *, DOSBase, 70, Dos)
  23
  24 /*  FUNCTION
  25         Compares two locks.
  26
  27     INPUTS
  28         lock1, lock2 - locks
  29
  30     RESULT
  31         LOCK_SAME        - locks points to the same object
  32         LOCK_SAME_VOLUME - locks are on the same volume
  33         LOCK_DIFFERENT   - locks are different
  34
  35     NOTES
  36
  37     EXAMPLE
  38
  39     BUGS
  40
  41     SEE ALSO
  42
  43     INTERNALS
  44
  45 *****************************************************************************/
  46 {
  47     AROS_LIBFUNC_INIT
  48
  49     struct IOFileSys iofs;
  50     struct FileHandle *fh1;
  51     struct FileHandle *fh2;
  52
  53     if(!SameDevice(lock1, lock2))
  54         return LOCK_DIFFERENT;
  55
  56     fh1 = (struct FileHandle *)BADDR(lock1);
  57     fh2 = (struct FileHandle *)BADDR(lock2);
  58
  59     /* Check if it is the same lock */
  60
  61     /* Prepare I/O request. */
  62     InitIOFS(&iofs, FSA_SAME_LOCK, DOSBase);
  63
  64     iofs.IOFS.io_Device = fh1->fh_Device;
  65     iofs.IOFS.io_Unit   = fh1->fh_Unit;
  66     iofs.io_Union.io_SAME_LOCK.io_Lock[0] = fh1->fh_Unit;
  67     iofs.io_Union.io_SAME_LOCK.io_Lock[1] = fh2->fh_Unit;
  68     iofs.io_Union.io_SAME_LOCK.io_Same = LOCK_DIFFERENT;
  69
  70     /* Send the request. */
  71     DosDoIO(&iofs.IOFS);
  72
  73     /* Set error code and return */
  74     SetIoErr(iofs.io_DosError);
  75
  76     if(iofs.io_DosError != 0)
  77         return LOCK_DIFFERENT;
  78     else
  79     {
  80         if(iofs.io_Union.io_SAME_LOCK.io_Same == LOCK_SAME)
  81             return LOCK_SAME;
  82         else
  83             return LOCK_SAME_VOLUME;
  84     }
  85
  86     return 0;
  87
  88     AROS_LIBFUNC_EXIT
  89 } /* SameLock */