/*
  $Header: /cvs/src/chrony/reference.h,v 1.13 2002/02/28 23:27:12 richard Exp $

  =======================================================================

  chronyd/chronyc - Programs for keeping computer clocks accurate.

 **********************************************************************
 * Copyright (C) Richard P. Curnow  1997-2002
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 * 
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 * 
 **********************************************************************

  =======================================================================

  This is the header file for the module that keeps track of the current
  reference.

  */

#ifndef GOT_REFERENCE_H
#define GOT_REFERENCE_H

#include "sysincl.h"

#include "ntp.h"
#include "reports.h"

/* Init function */
extern void REF_Initialise(void);

/* Fini function */
extern void REF_Finalise(void);

/* Function which takes a local cooked time and returns the estimated
   time of the reference.  It also returns the other parameters
   required for forming the outgoing NTP packet.

   local_time is the cooked local time returned by the LCL module

   is_synchronised indicates whether we are synchronised to anything
   at the moment.

   leap indicates the current leap status

   stratum is the stratum of this machine, when considered to be sync'd to the
   reference
   
   ref_id is the reference_id of the source

   ref_time is the time at which the we last set the reference source up

   root_delay is the root delay of the sample we are using

   root_dispersion is the root dispersion of the sample we are using, with all the
   skew etc added on.

   */

extern void REF_GetReferenceParams
(
 struct timeval *local_time,
 int *is_synchronised,
 NTP_Leap *leap,
 int *stratum,
 unsigned long *ref_id,
 struct timeval *ref_time,
 double *root_delay,
 double *root_dispersion
);

/* Function called by the clock selection process to register a new
   reference source and its parameters

   stratum is the stratum of the reference

   leap is the leap status read from the source

   ref_id is the reference id of the reference

   ref_time is the time at which the parameters are assumed to be
   correct, in terms of local time

   frequency is the amount of local clock gain relative to the
   reference per unit time interval of the local clock

   skew is the maximum estimated frequency error (so we are within
   [frequency+-skew])

   root_delay is the root delay of the sample we are using

   root_dispersion is the root dispersion of the sample we are using

   */

extern void REF_SetReference
(
 int stratum,
 NTP_Leap leap,
 unsigned long ref_id,
 IPAddr *ref_ip,
 struct timeval *ref_time,
 double offset,
 double frequency,
 double skew,
 double root_delay,
 double root_dispersion
);

extern void REF_SetManualReference
(
 struct timeval *ref_time,
 double offset,
 double frequency,
 double skew
);

/* Mark the local clock as unsynchronised */
extern void
REF_SetUnsynchronised(void);

/* Return the current stratum of this host or zero if the host is not
   synchronised */
extern int REF_GetOurStratum(void);

/* Modify the setting for the maximum skew we are prepared to allow updates on (in ppm). */
extern void REF_ModifyMaxupdateskew(double new_max_update_skew);

extern void REF_EnableLocal(int stratum);
extern void REF_DisableLocal(void);
extern int REF_IsLocalActive(void);

extern void REF_GetTrackingReport(RPT_TrackingReport *rep);

extern void REF_CycleLogFile(void);

#endif /* GOT_REFERENCE_H */
