ntp-time.h

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// -*- C++ -*-

// $Id: ntp-time.h 71526 2006-03-14 06:14:35Z jtc $
/*
 * Copyright (c) 1995 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the Network Research
 *      Group at Lawrence Berkeley National Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 */

#ifndef TAO_AV_NTP_TIME_H
#define TAO_AV_NTP_TIME_H
#include /**/ "ace/pre.h"

#include "orbsvcs/AV/RTCP.h"

/*
 * convert microseconds to fraction of second * 2^32 (i.e., the lsw of
 * a 64-bit ntp timestamp).  This routine uses the factorization
 * 2^32/10^6 = 4096 + 256 - 1825/32 which results in a max conversion
 * error of 3 * 10^-7 and an average error of half that.
 */
ACE_INLINE u_int usec2ntp(u_int usec)
{
  u_int const t = (usec * 1825) >> 5;
  return ((usec << 12) + (usec << 8) - t);
}

/*
 * Number of seconds between 1-Jan-1900 and 1-Jan-1970
 */
const ACE_UINT32 GETTIMEOFDAY_TO_NTP_OFFSET = 2208988800U;

/*
 * Return a 64-bit ntp timestamp (UTC time relative to Jan 1, 1970).
 * gettimeofday conveniently gives us the correct reference -- we just
 * need to convert sec+usec to a 64-bit fixed point (with binary point
 * at bit 32).
 */
ACE_INLINE TAO_AV_RTCP::ntp64
ntp64time (timeval tv)
{
  TAO_AV_RTCP::ntp64 n;
  n.upper = (u_int)tv.tv_sec + GETTIMEOFDAY_TO_NTP_OFFSET;
  n.lower = usec2ntp((u_int)tv.tv_usec);
  return (n);
}

ACE_INLINE ACE_UINT32
ntptime (timeval t)
{
        u_int s = (u_int)t.tv_sec + GETTIMEOFDAY_TO_NTP_OFFSET;
        return (s << 16 | usec2ntp((u_int)t.tv_usec) >> 16);
}

ACE_INLINE ACE_UINT32 
ntptime()
{
  //
 ACE_Time_Value tim_v = ACE_OS::gettimeofday();
 //struct timeval tv = (timeval) tim_v;
        return (ntptime ((timeval) tim_v));
}

ACE_INLINE timeval unixtime()
{
  ACE_Time_Value tv = ACE_OS::gettimeofday();
        return ((timeval) tv);
}
#include /**/ "ace/post.h"
#endif /* TAO_AV_NTP_TIME_H */

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