/* Duplicate a protid

   Copyright (C) 1993,94,95,96,2001 Free Software Foundation, Inc.

   This file is part of the GNU Hurd.

   The GNU Hurd is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   The GNU Hurd is distributed in the hope that it will be useful, 
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with the GNU Hurd; see the file COPYING.  If not, write to
   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include <string.h>
#include "priv.h"

/* Return a duplicate of CRED in DUP, sharing the same peropen and hook.  A
   non-null hook may be used to detect that this is a duplicate by
   trivfs_protid_create_hook.  */
error_t
trivfs_protid_dup (struct trivfs_protid *cred, struct trivfs_protid **dup)
{
  struct trivfs_protid *new;
  error_t err = ports_create_port (cred->po->cntl->protid_class,
				   cred->po->cntl->protid_bucket,
				   sizeof (struct trivfs_protid), 
				   &new);

  if (! err)
    {
      new->po = cred->po;
      refcount_ref (&new->po->refcnt);
      new->isroot = cred->isroot;

      err = iohelp_dup_iouser (&new->user, cred->user);
      if (err)
        {
	  ports_port_deref (new);
	  return err;
	}

      new->realnode = cred->realnode;
      mach_port_mod_refs (mach_task_self (), new->realnode,
			  MACH_PORT_RIGHT_SEND, 1);

      new->hook = cred->hook;

      if (trivfs_protid_create_hook)
	err = (*trivfs_protid_create_hook) (new);
      if (err)
	{
	  mach_port_deallocate (mach_task_self (), new->realnode);
	  /* Signal that the user destroy hook shouldn't be called on NEW.  */
	  new->realnode = MACH_PORT_NULL;
	  ports_port_deref (new);
	}
      else
	*dup = new;
    }

  return err;
}