/*
 * This file is part of the Sofia-SIP package
 *
 * Copyright (C) 2005 Nokia Corporation.
 *
 * Contact: Pekka Pessi <pekka.pessi@nokia.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

/**@ingroup su_time
 * @CFILE su_time0.c
 * @brief su_time() implementation
 *
 * The file su_time0.c contains implementation of OS-independent wallclock
 * time with microsecond resolution.
 *
 * @author Pekka Pessi <Pekka.Pessi@nokia.com>
 * @author Jari Selin <Jari.Selin@nokia.com>
 * 
 * @date Created: Fri May 10 18:13:19 2002 ppessi
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>

#include "sofia-sip/su_types.h"
#include "sofia-sip/su_time.h"
#include "su_module_debug.h"

#include <time.h>

#if HAVE_SYS_TIME_H
#include <sys/time.h> /* Get struct timeval */
#endif

#if defined(__MINGW32__)
#define HAVE_FILETIME 1
#include <windows.h>
#endif

#if HAVE_FILETIME
#define HAVE_FILETIME 1
#include <windows.h>
#endif

/** Seconds from 1.1.1900 to 1.1.1970 */
#define NTP_EPOCH 2208988800UL 
#define E9 (1000000000U)
#define E7 (10000000U)

/* Hooks for testing timing and timers */
void (*_su_time)(su_time_t *tv);
uint64_t (*_su_nanotime)(uint64_t *);

/** Get current time.
 *
 * The function @c su_time() fills its argument with the current NTP
 * timestamp expressed as a su_time_t structure.
 *
 * @param tv pointer to the timeval object
 */
void su_time(su_time_t *tv)
{
#if HAVE_GETTIMEOFDAY
  if (tv) {
    gettimeofday((struct timeval *)tv, NULL);
    tv->tv_sec += NTP_EPOCH;
  }
#elif HAVE_FILETIME
  union {
    FILETIME       ft[1];
    ULARGE_INTEGER ull[1];
  } date;

  GetSystemTimeAsFileTime(date.ft);

  tv->tv_usec = (unsigned long) ((date.ull->QuadPart % E7) / 10);
  tv->tv_sec = (unsigned long) ((date.ull->QuadPart / E7) - 
    /* 1900-Jan-01 - 1601-Jan-01: 299 years, 72 leap years */
    (299 * 365 + 72) * 24 * 60 * (uint64_t)60);
#else
#error no su_time() implementation
#endif

  if (_su_time)
    _su_time(tv);
}

/** Get current time as nanoseconds since epoch.
 *
 * Return the current NTP timestamp expressed as nanoseconds since epoch
 * (January 1st 1900).
 *
 * @param return_time optional pointer to current time to return
 *
 * @return Nanoseconds since epoch
 */
su_nanotime_t su_nanotime(su_nanotime_t *return_time)
{
  su_nanotime_t now;

  if (!return_time)
    return_time = &now;

#if HAVE_CLOCK_GETTIME
  {
    struct timespec tv;
  
    if (clock_gettime(CLOCK_REALTIME, &tv) == 0) {
      now = ((su_nanotime_t)tv.tv_sec + NTP_EPOCH) * E9 + tv.tv_nsec;
      *return_time = now;
      if (_su_nanotime)
	return _su_nanotime(return_time);
      return now;
    }
  }
#endif

#if HAVE_FILETIME
  {
    union {
      FILETIME       ft[1];
      ULARGE_INTEGER ull[1];
    } date;
    
    GetSystemTimeAsFileTime(date.ft);

    now = 100 * 
      (date.ull->QuadPart - 
       /* 1900-Jan-01 - 1601-Jan-01: 299 years, 72 leap years */
       ((su_nanotime_t)(299 * 365 + 72) * 24 * 60 * 60) * E7);
  }
#elif HAVE_GETTIMEOFDAY
  {
    struct timeval tv;

    gettimeofday(&tv, NULL);

    now = ((su_nanotime_t)tv.tv_sec + NTP_EPOCH) * E9 + tv.tv_usec * 1000;
  }
#else
  now = ((su_nanotime_t)time() + NTP_EPOCH) * E9;
#endif

  *return_time = now;

  if (_su_nanotime)
    return _su_nanotime(return_time);

  return now;
}

/** Get current time as nanoseconds.
 *
 * Return the current time expressed as nanoseconds. The time returned is
 * monotonic and never goes back - if the underlying system supports such a
 * clock.
 *
 * @param return_time optional pointer to return the current time 
 *
 * @return Current time as nanoseconds 
 */
su_nanotime_t su_monotime(su_nanotime_t *return_time)
{
#if HAVE_CLOCK_GETTIME && CLOCK_MONOTONIC
  {
    struct timespec tv;
  
    if (clock_gettime(CLOCK_MONOTONIC, &tv) == 0) {
      su_nanotime_t now = (su_nanotime_t)tv.tv_sec * E9 + tv.tv_nsec;
      if (return_time)
	*return_time = now;
      return now;
    }
  }
#endif

#if HAVE_NANOUPTIME
  {
    struct timespec tv;
  
    nanouptime(&tv);
    now = (su_nanotime_t)tv.tv_sec * E9 + tv.tv_nsec;
    if (return_time)
      *return_time = now;
    return now;
  }
#elif HAVE_MICROUPTIME
  {
    struct timeval tv;

    microuptime(&tv);
    now = (su_nanotime_t)tv.tv_sec * E9 + tv.tv_usec * 1000;
    if (return_time)
      *return_time = now;
    return now;
  }
#else
  return su_nanotime(return_time);
#endif
}