/*
*******************************************************************************
*  Copyright (c) 1996 Martin Poole                            *
*******************************************************************************
**
** WARNING !!  WARNING !! WARNING !! WARNING !! WARNING !! WARNING !!
**
** Any changes to be made to this file should first be checked with
** mplib1 source control for library integrity.
**
** mplib1 source control can be reached at  mplib1@quatermass.co.uk
** 
*
*  $Source: /home/cvs/cvsroot/onelan/onelan/src/mplib1/libsrc/bpo_l_007.c,v $
*  $Author: mpoole $
*  $Date: 2002/10/07 09:37:36 $
*  $Revision: 1.2 $
*
*******************************************************************************
*
* Change History
*
* $Log: bpo_l_007.c,v $
* Revision 1.2  2002/10/07 09:37:36  mpoole
* Initial checkin of mplib1-3.1.0
*
* Revision 1.1  2002/10/07 09:36:53  mpoole
* Initial checkin of mplib1-3.1.0
*
*
*******************************************************************************
*/

#ident "$Header: /home/cvs/cvsroot/onelan/onelan/src/mplib1/libsrc/bpo_l_007.c,v 1.2 2002/10/07 09:37:36 mpoole Exp $"

/* ------------------------------------------------------------------
    Include files
   ------------------------------------------------------------------ */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/ipc.h>
#include <sys/shm.h>

#include <mplib1/mplib1_config.h>
#include <mplib1/bpo_lock.h>
#include <mplib1/bpo_list.h>
#include <include/bpo_list_internal.h>
#include <mplib1/bpo_init.h>

/* ------------------------------------------------------------------
    defines
   ------------------------------------------------------------------ */

/* ------------------------------------------------------------------
    Code starts here
   ------------------------------------------------------------------ */

bpo_Node_t *
bpo_Add_Node_Before( bpo_Node_t *node1, bpo_Node_t *node2 )
{
    bpo_List_t *lp;
    if (Get_SODB_Base( node1 ) != Get_SODB_Base( node2 ))
	return(NULL);
    lp = GRPTR( node1, node1->lno_List );
    if (lp && lp->lno_me==node1->lno_List)
    {
	bpo_pid_Lock( &lp->lno_Pid_Lock );
	if (node1->lno_Pred && node2->lno_Pred==(off_t)0)
	{
	    node2->lno_Succ = node1->lno_me;
	    node2->lno_Pred = node1->lno_Pred;
	    GNNODE( node1, node1->lno_Pred)->lno_Succ = node2->lno_me;
	    node1->lno_Pred = node2->lno_me;
	    node2->lno_List = node1->lno_List;
	    lp->lno_count++;
	    lp->lno_serial_nbr++;
	}
	bpo_pid_Unlock( &lp->lno_Pid_Lock );
    }
    return(node2);
}

/* -- End of File -- */