text: /*
   * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
   *
   * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   *
   * This file contains Original Code and/or Modifications of Original Code
   * as defined in and that are subject to the Apple Public Source License
   * Version 2.0 (the 'License'). You may not use this file except in
   * compliance with the License. The rights granted to you under the License
   * may not be used to create, or enable the creation or redistribution of,
   * unlawful or unlicensed copies of an Apple operating system, or to
   * circumvent, violate, or enable the circumvention or violation of, any
   * terms of an Apple operating system software license agreement.
   *
   * Please obtain a copy of the License at
   * http://www.opensource.apple.com/apsl/ and read it before using this file.
   *
   * The Original Code and all software distributed under the License are
   * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
   * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
   * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
   * Please see the License for the specific language governing rights and
   * limitations under the License.
   *
   * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
   */
  /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
  /*
   * Copyright (c) 1982, 1986, 1989, 1993
   *	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 University of
   *	California, Berkeley and its contributors.
   * 4. Neither the name of the University nor the names of its contributors
   *    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
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * 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
   * SUCH DAMAGE.
   *
   *	@(#)kern_time.c	8.4 (Berkeley) 5/26/95
   */
  /*
   * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
   * support for mandatory and extensible security protections.  This notice
   * is included in support of clause 2.2 (b) of the Apple Public License,
   * Version 2.0.
   */
  
  #include <sys/param.h>
  #include <sys/resourcevar.h>
  #include <sys/kernel.h>
  #include <sys/systm.h>
  #include <sys/proc_internal.h>
  #include <sys/kauth.h>
  #include <sys/vnode.h>
  #include <sys/time.h>
  #include <sys/priv.h>
  
  #include <sys/mount_internal.h>
  #include <sys/sysproto.h>
  #include <sys/signalvar.h>
  #include <sys/protosw.h> /* for net_uptime2timeval() */
  
  #include <kern/clock.h>
  #include <kern/task.h>
  #include <kern/thread_call.h>
  #if CONFIG_MACF
  #include <security/mac_framework.h>
  #endif
  #include <IOKit/IOBSD.h>
  #include <sys/time.h>
  #include <kern/remote_time.h>
  
  #define HZ      100     /* XXX */
  
  /* simple lock used to access timezone, tz structure */
  lck_spin_t * tz_slock;
  lck_grp_t * tz_slock_grp;
  lck_attr_t * tz_slock_attr;
  lck_grp_attr_t  *tz_slock_grp_attr;
  
  static void             setthetime(
  	struct timeval  *tv);
  
  void time_zone_slock_init(void);
  static boolean_t timeval_fixusec(struct timeval *t1);
  
  /*
   * Time of day and interval timer support.
   *
   * These routines provide the kernel entry points to get and set
   * the time-of-day and per-process interval timers.  Subroutines
   * here provide support for adding and subtracting timeval structures
   * and decrementing interval timers, optionally reloading the interval
   * timers when they expire.
   */
  /* ARGSUSED */
  int
  gettimeofday(
  	struct proc     *p,
  	struct gettimeofday_args *uap,
  	__unused int32_t *retval)
  {
  	int error = 0;
  	struct timezone ltz; /* local copy */
  	clock_sec_t secs;
  	clock_usec_t usecs;
  	uint64_t mach_time;
  
  	if (uap->tp || uap->mach_absolute_time) {
  		clock_gettimeofday_and_absolute_time(&secs, &usecs, &mach_time);
  	}
  
  	if (uap->tp) {
  		/* Casting secs through a uint32_t to match arm64 commpage */
  		if (IS_64BIT_PROCESS(p)) {
  			struct user64_timeval user_atv = {};
  			user_atv.tv_sec = (uint32_t)secs;
  			user_atv.tv_usec = usecs;
  			error = copyout(&user_atv, uap->tp, sizeof(user_atv));
  		} else {
  			struct user32_timeval user_atv = {};
  			user_atv.tv_sec = (uint32_t)secs;
  			user_atv.tv_usec = usecs;
  			error = copyout(&user_atv, uap->tp, sizeof(user_atv));
  		}
  		if (error) {
  			return error;
  		}
  	}
  
  	if (uap->tzp) {
  		lck_spin_lock(tz_slock);
  		ltz = tz;
  		lck_spin_unlock(tz_slock);
  
  		error = copyout((caddr_t)&ltz, CAST_USER_ADDR_T(uap->tzp), sizeof(tz));
  	}
  
  	if (error == 0 && uap->mach_absolute_time) {
  		error = copyout(&mach_time, uap->mach_absolute_time, sizeof(mach_time));
  	}
  
  	return error;
  }
  
  /*
   * XXX Y2038 bug because of setthetime() argument
   */
  /* ARGSUSED */
  int
  settimeofday(__unused struct proc *p, struct settimeofday_args  *uap, __unused int32_t *retval)
  {
  	struct timeval atv;
  	struct timezone atz;
  	int error;
  
  	bzero(&atv, sizeof(atv));
  
  	/* Check that this task is entitled to set the time or it is root */
  	if (!IOTaskHasEntitlement(current_task(), SETTIME_ENTITLEMENT)) {
  #if CONFIG_MACF
  		error = mac_system_check_settime(kauth_cred_get());
  		if (error) {
  			return error;
  		}
  #endif
  #ifndef CONFIG_EMBEDDED
  		if ((error = suser(kauth_cred_get(), &p->p_acflag))) {
  			return error;
  		}
  #endif
  	}
  
  	/* Verify all parameters before changing time */
  	if (uap->tv) {
  		if (IS_64BIT_PROCESS(p)) {
  			struct user64_timeval user_atv;
  			error = copyin(uap->tv, &user_atv, sizeof(user_atv));
  			atv.tv_sec = user_atv.tv_sec;
  			atv.tv_usec = user_atv.tv_usec;
  		} else {
  			struct user32_timeval user_atv;
  			error = copyin(uap->tv, &user_atv, sizeof(user_atv));
  			atv.tv_sec = user_atv.tv_sec;
  			atv.tv_usec = user_atv.tv_usec;
  		}
  		if (error) {
  			return error;
  		}
  	}
  	if (uap->tzp && (error = copyin(uap->tzp, (caddr_t)&atz, sizeof(atz)))) {
  		return error;
  	}
  	if (uap->tv) {
  		/* only positive values of sec/usec are accepted */
  		if (atv.tv_sec < 0 || atv.tv_usec < 0) {
  			return EPERM;
  		}
  		if (!timeval_fixusec(&atv)) {
  			return EPERM;
  		}
  		setthetime(&atv);
  	}
  	if (uap->tzp) {
  		lck_spin_lock(tz_slock);
  		tz = atz;
  		lck_spin_unlock(tz_slock);
  	}
  	return 0;
  }
  
  static void
  setthetime(
  	struct timeval  *tv)
  {
  	clock_set_calendar_microtime(tv->tv_sec, tv->tv_usec);
  }
  
  /*
   *	Verify the calendar value.  If negative,
   *	reset to zero (the epoch).
   */
  void
  inittodr(
  	__unused time_t base)
  {
  	struct timeval  tv;
  
  	/*
  	 * Assertion:
  	 * The calendar has already been
  	 * set up from the platform clock.
  	 *
  	 * The value returned by microtime()
  	 * is gotten from the calendar.
  	 */
  	microtime(&tv);
  
  	if (tv.tv_sec < 0 || tv.tv_usec < 0) {
  		printf("WARNING: preposterous time in Real Time Clock");
  		tv.tv_sec = 0;          /* the UNIX epoch */
  		tv.tv_usec = 0;
  		setthetime(&tv);
  		printf(" -- CHECK AND RESET THE DATE!\n");
  	}
  }
  
  time_t
  boottime_sec(void)
  {
  	clock_sec_t             secs;
  	clock_nsec_t    nanosecs;
  
  	clock_get_boottime_nanotime(&secs, &nanosecs);
  	return secs;
  }
  
  void
  boottime_timeval(struct timeval *tv)
  {
  	clock_sec_t             secs;
  	clock_usec_t    microsecs;
  
  	clock_get_boottime_microtime(&secs, &microsecs);
  
  	tv->tv_sec = secs;
  	tv->tv_usec = microsecs;
  }
  
  /*
   * Get value of an interval timer.  The process virtual and
   * profiling virtual time timers are kept internally in the
   * way they are specified externally: in time until they expire.
   *
   * The real time interval timer expiration time (p_rtime)
   * is kept as an absolute time rather than as a delta, so that
   * it is easy to keep periodic real-time signals from drifting.
   *
   * The real time timer is processed by a callout routine.
   * Since a callout may be delayed in real time due to
   * other processing in the system, it is possible for the real
   * time callout routine (realitexpire, given below), to be delayed
   * in real time past when it is supposed to occur.  It does not
   * suffice, therefore, to reload the real time .it_value from the
   * real time .it_interval.  Rather, we compute the next time in
   * absolute time when the timer should go off.
   *
   * Returns:	0			Success
   *		EINVAL			Invalid argument
   *	copyout:EFAULT			Bad address
   */
  /* ARGSUSED */
  int
  getitimer(struct proc *p, struct getitimer_args *uap, __unused int32_t *retval)
  {
  	struct itimerval aitv;
  
  	if (uap->which > ITIMER_PROF) {
  		return EINVAL;
  	}
  
  	bzero(&aitv, sizeof(aitv));
  
  	proc_spinlock(p);
  	switch (uap->which) {
  	case ITIMER_REAL:
  		/*
  		 * If time for real time timer has passed return 0,
  		 * else return difference between current time and
  		 * time for the timer to go off.
  		 */
  		aitv = p->p_realtimer;
  		if (timerisset(&p->p_rtime)) {
  			struct timeval          now;
  
  			microuptime(&now);
  			if (timercmp(&p->p_rtime, &now, <)) {
  				timerclear(&aitv.it_value);
  			} else {
  				aitv.it_value = p->p_rtime;
  				timevalsub(&aitv.it_value, &now);
  			}
  		} else {
  			timerclear(&aitv.it_value);
  		}
  		break;
  
  	case ITIMER_VIRTUAL:
  		aitv = p->p_vtimer_user;
  		break;
  
  	case ITIMER_PROF:
  		aitv = p->p_vtimer_prof;
  		break;
  	}
  
  	proc_spinunlock(p);
  
  	if (IS_64BIT_PROCESS(p)) {
  		struct user64_itimerval user_itv;
  		bzero(&user_itv, sizeof(user_itv));
  		user_itv.it_interval.tv_sec = aitv.it_interval.tv_sec;
  		user_itv.it_interval.tv_usec = aitv.it_interval.tv_usec;
  		user_itv.it_value.tv_sec = aitv.it_value.tv_sec;
  		user_itv.it_value.tv_usec = aitv.it_value.tv_usec;
  		return copyout((caddr_t)&user_itv, uap->itv, sizeof(user_itv));
  	} else {
  		struct user32_itimerval user_itv;
  		bzero(&user_itv, sizeof(user_itv));
  		user_itv.it_interval.tv_sec = aitv.it_interval.tv_sec;
  		user_itv.it_interval.tv_usec = aitv.it_interval.tv_usec;
  		user_itv.it_value.tv_sec = aitv.it_value.tv_sec;
  		user_itv.it_value.tv_usec = aitv.it_value.tv_usec;
  		return copyout((caddr_t)&user_itv, uap->itv, sizeof(user_itv));
  	}
  }
  
  /*
   * Returns:	0			Success
   *		EINVAL			Invalid argument
   *	copyin:EFAULT			Bad address
   *	getitimer:EINVAL		Invalid argument
   *	getitimer:EFAULT		Bad address
   */
  /* ARGSUSED */
  int
  setitimer(struct proc *p, struct setitimer_args *uap, int32_t *retval)
  {
  	struct itimerval aitv;
  	user_addr_t itvp;
  	int error;
  
  	bzero(&aitv, sizeof(aitv));
  
  	if (uap->which > ITIMER_PROF) {
  		return EINVAL;
  	}
  	if ((itvp = uap->itv)) {
  		if (IS_64BIT_PROCESS(p)) {
  			struct user64_itimerval user_itv;
  			if ((error = copyin(itvp, (caddr_t)&user_itv, sizeof(user_itv)))) {
  				return error;
  			}
  			aitv.it_interval.tv_sec = user_itv.it_interval.tv_sec;
  			aitv.it_interval.tv_usec = user_itv.it_interval.tv_usec;
  			aitv.it_value.tv_sec = user_itv.it_value.tv_sec;
  			aitv.it_value.tv_usec = user_itv.it_value.tv_usec;
  		} else {
  			struct user32_itimerval user_itv;
  			if ((error = copyin(itvp, (caddr_t)&user_itv, sizeof(user_itv)))) {
  				return error;
  			}
  			aitv.it_interval.tv_sec = user_itv.it_interval.tv_sec;
  			aitv.it_interval.tv_usec = user_itv.it_interval.tv_usec;
  			aitv.it_value.tv_sec = user_itv.it_value.tv_sec;
  			aitv.it_value.tv_usec = user_itv.it_value.tv_usec;
  		}
  	}
  	if ((uap->itv = uap->oitv) && (error = getitimer(p, (struct getitimer_args *)uap, retval))) {
  		return error;
  	}
  	if (itvp == 0) {
  		return 0;
  	}
  	if (itimerfix(&aitv.it_value) || itimerfix(&aitv.it_interval)) {
  		return EINVAL;
  	}
  
  	switch (uap->which) {
  	case ITIMER_REAL:
  		proc_spinlock(p);
  		if (timerisset(&aitv.it_value)) {
  			microuptime(&p->p_rtime);
  			timevaladd(&p->p_rtime, &aitv.it_value);
  			p->p_realtimer = aitv;
  			if (!thread_call_enter_delayed_with_leeway(p->p_rcall, NULL,
  			    tvtoabstime(&p->p_rtime), 0, THREAD_CALL_DELAY_USER_NORMAL)) {
  				p->p_ractive++;
  			}
  		} else {
  			timerclear(&p->p_rtime);
  			p->p_realtimer = aitv;
  			if (thread_call_cancel(p->p_rcall)) {
  				p->p_ractive--;
  			}
  		}
  		proc_spinunlock(p);
  
  		break;
  
  
  	case ITIMER_VIRTUAL:
  		if (timerisset(&aitv.it_value)) {
  			task_vtimer_set(p->task, TASK_VTIMER_USER);
  		} else {
  			task_vtimer_clear(p->task, TASK_VTIMER_USER);
  		}
  
  		proc_spinlock(p);
  		p->p_vtimer_user = aitv;
  		proc_spinunlock(p);
  		break;
  
  	case ITIMER_PROF:
  		if (timerisset(&aitv.it_value)) {
  			task_vtimer_set(p->task, TASK_VTIMER_PROF);
  		} else {
  			task_vtimer_clear(p->task, TASK_VTIMER_PROF);
  		}
  
  		proc_spinlock(p);
  		p->p_vtimer_prof = aitv;
  		proc_spinunlock(p);
  		break;
  	}
  
  	return 0;
  }
  
  /*
   * Real interval timer expired:
   * send process whose timer expired an alarm signal.
   * If time is not set up to reload, then just return.
   * Else compute next time timer should go off which is > current time.
   * This is where delay in processing this timeout causes multiple
   * SIGALRM calls to be compressed into one.
   */
  void
  realitexpire(
  	struct proc *p)
  {
  	struct proc *r;
  	struct timeval t;
  
  	r = proc_find(p->p_pid);
  
  	proc_spinlock(p);
  
  	assert(p->p_ractive > 0);
  
  	if (--p->p_ractive > 0 || r != p) {
  		/*
  		 * bail, because either proc is exiting
  		 * or there's another active thread call
  		 */
  		proc_spinunlock(p);
  
  		if (r != NULL) {
  			proc_rele(r);
  		}
  		return;
  	}
  
  	if (!timerisset(&p->p_realtimer.it_interval)) {
  		/*
  		 * p_realtimer was cleared while this call was pending,
  		 * send one last SIGALRM, but don't re-arm
  		 */
  		timerclear(&p->p_rtime);
  		proc_spinunlock(p);
  
  		psignal(p, SIGALRM);
  		proc_rele(p);
  		return;
  	}
  
  	proc_spinunlock(p);
  
  	/*
  	 * Send the signal before re-arming the next thread call,
  	 * so in case psignal blocks, we won't create yet another thread call.
  	 */
  
  	psignal(p, SIGALRM);
  
  	proc_spinlock(p);
  
  	/* Should we still re-arm the next thread call? */
  	if (!timerisset(&p->p_realtimer.it_interval)) {
  		timerclear(&p->p_rtime);
  		proc_spinunlock(p);
  
  		proc_rele(p);
  		return;
  	}
  
  	microuptime(&t);
  	timevaladd(&p->p_rtime, &p->p_realtimer.it_interval);
  
  	if (timercmp(&p->p_rtime, &t, <=)) {
  		if ((p->p_rtime.tv_sec + 2) >= t.tv_sec) {
  			for (;;) {
  				timevaladd(&p->p_rtime, &p->p_realtimer.it_interval);
  				if (timercmp(&p->p_rtime, &t, >)) {
  					break;
  				}
  			}
  		} else {
  			p->p_rtime = p->p_realtimer.it_interval;
  			timevaladd(&p->p_rtime, &t);
  		}
  	}
  
  	assert(p->p_rcall != NULL);
  
  	if (!thread_call_enter_delayed_with_leeway(p->p_rcall, NULL, tvtoabstime(&p->p_rtime), 0,
  	    THREAD_CALL_DELAY_USER_NORMAL)) {
  		p->p_ractive++;
  	}
  
  	proc_spinunlock(p);
  
  	proc_rele(p);
  }
  
  /*
   * Called once in proc_exit to clean up after an armed or pending realitexpire
   *
   * This will only be called after the proc refcount is drained,
   * so realitexpire cannot be currently holding a proc ref.
   * i.e. it will/has gotten PROC_NULL from proc_find.
   */
  void
  proc_free_realitimer(proc_t p)
  {
  	proc_spinlock(p);
  
  	assert(p->p_rcall != NULL);
  	assert(p->p_refcount == 0);
  
  	timerclear(&p->p_realtimer.it_interval);
  
  	if (thread_call_cancel(p->p_rcall)) {
  		assert(p->p_ractive > 0);
  		p->p_ractive--;
  	}
  
  	while (p->p_ractive > 0) {
  		proc_spinunlock(p);
  
  		delay(1);
  
  		proc_spinlock(p);
  	}
  
  	thread_call_t call = p->p_rcall;
  	p->p_rcall = NULL;
  
  	proc_spinunlock(p);
  
  	thread_call_free(call);
  }
  
  /*
   * Check that a proposed value to load into the .it_value or
   * .it_interval part of an interval timer is acceptable.
   */
  int
  itimerfix(
  	struct timeval *tv)
  {
  	if (tv->tv_sec < 0 || tv->tv_sec > 100000000 ||
  	    tv->tv_usec < 0 || tv->tv_usec >= 1000000) {
  		return EINVAL;
  	}
  	return 0;
  }
  
  int
  timespec_is_valid(const struct timespec *ts)
  {
  	/* The INT32_MAX limit ensures the timespec is safe for clock_*() functions
  	 * which accept 32-bit ints. */
  	if (ts->tv_sec < 0 || ts->tv_sec > INT32_MAX ||
  	    ts->tv_nsec < 0 || (unsigned long long)ts->tv_nsec > NSEC_PER_SEC) {
  		return 0;
  	}
  	return 1;
  }
  
  /*
   * Decrement an interval timer by a specified number
   * of microseconds, which must be less than a second,
   * i.e. < 1000000.  If the timer expires, then reload
   * it.  In this case, carry over (usec - old value) to
   * reduce the value reloaded into the timer so that
   * the timer does not drift.  This routine assumes
   * that it is called in a context where the timers
   * on which it is operating cannot change in value.
   */
  int
  itimerdecr(proc_t p,
      struct itimerval *itp, int usec)
  {
  	proc_spinlock(p);
  
  	if (itp->it_value.tv_usec < usec) {
  		if (itp->it_value.tv_sec == 0) {
  			/* expired, and already in next interval */
  			usec -= itp->it_value.tv_usec;
  			goto expire;
  		}
  		itp->it_value.tv_usec += 1000000;
  		itp->it_value.tv_sec--;
  	}
  	itp->it_value.tv_usec -= usec;
  	usec = 0;
  	if (timerisset(&itp->it_value)) {
  		proc_spinunlock(p);
  		return 1;
  	}
  	/* expired, exactly at end of interval */
  expire:
  	if (timerisset(&itp->it_interval)) {
  		itp->it_value = itp->it_interval;
  		if (itp->it_value.tv_sec > 0) {
  			itp->it_value.tv_usec -= usec;
  			if (itp->it_value.tv_usec < 0) {
  				itp->it_value.tv_usec += 1000000;
  				itp->it_value.tv_sec--;
  			}
  		}
  	} else {
  		itp->it_value.tv_usec = 0;              /* sec is already 0 */
  	}
  	proc_spinunlock(p);
  	return 0;
  }
  
  /*
   * Add and subtract routines for timevals.
   * N.B.: subtract routine doesn't deal with
   * results which are before the beginning,
   * it just gets very confused in this case.
   * Caveat emptor.
   */
  void
  timevaladd(
  	struct timeval *t1,
  	struct timeval *t2)
  {
  	t1->tv_sec += t2->tv_sec;
  	t1->tv_usec += t2->tv_usec;
  	timevalfix(t1);
  }
  void
  timevalsub(
  	struct timeval *t1,
  	struct timeval *t2)
  {
  	t1->tv_sec -= t2->tv_sec;
  	t1->tv_usec -= t2->tv_usec;
  	timevalfix(t1);
  }
  void
  timevalfix(
  	struct timeval *t1)
  {
  	if (t1->tv_usec < 0) {
  		t1->tv_sec--;
  		t1->tv_usec += 1000000;
  	}
  	if (t1->tv_usec >= 1000000) {
  		t1->tv_sec++;
  		t1->tv_usec -= 1000000;
  	}
  }
  
  static boolean_t
  timeval_fixusec(
  	struct timeval *t1)
  {
  	assert(t1->tv_usec >= 0);
  	assert(t1->tv_sec >= 0);
  
  	if (t1->tv_usec >= 1000000) {
  		if (os_add_overflow(t1->tv_sec, t1->tv_usec / 1000000, &t1->tv_sec)) {
  			return FALSE;
  		}
  		t1->tv_usec = t1->tv_usec % 1000000;
  	}
  
  	return TRUE;
  }
  
  /*
   * Return the best possible estimate of the time in the timeval
   * to which tvp points.
   */
  void
  microtime(
  	struct timeval  *tvp)
  {
  	clock_sec_t             tv_sec;
  	clock_usec_t    tv_usec;
  
  	clock_get_calendar_microtime(&tv_sec, &tv_usec);
  
  	tvp->tv_sec = tv_sec;
  	tvp->tv_usec = tv_usec;
  }
  
  void
  microtime_with_abstime(
  	struct timeval  *tvp, uint64_t *abstime)
  {
  	clock_sec_t             tv_sec;
  	clock_usec_t    tv_usec;
  
  	clock_get_calendar_absolute_and_microtime(&tv_sec, &tv_usec, abstime);
  
  	tvp->tv_sec = tv_sec;
  	tvp->tv_usec = tv_usec;
  }
  
  void
  microuptime(
  	struct timeval  *tvp)
  {
  	clock_sec_t             tv_sec;
  	clock_usec_t    tv_usec;
  
  	clock_get_system_microtime(&tv_sec, &tv_usec);
  
  	tvp->tv_sec = tv_sec;
  	tvp->tv_usec = tv_usec;
  }
  
  /*
   * Ditto for timespec.
   */
  void
  nanotime(
  	struct timespec *tsp)
  {
  	clock_sec_t             tv_sec;
  	clock_nsec_t    tv_nsec;
  
  	clock_get_calendar_nanotime(&tv_sec, &tv_nsec);
  
  	tsp->tv_sec = tv_sec;
  	tsp->tv_nsec = tv_nsec;
  }
  
  void
  nanouptime(
  	struct timespec *tsp)
  {
  	clock_sec_t             tv_sec;
  	clock_nsec_t    tv_nsec;
  
  	clock_get_system_nanotime(&tv_sec, &tv_nsec);
  
  	tsp->tv_sec = tv_sec;
  	tsp->tv_nsec = tv_nsec;
  }
  
  uint64_t
  tvtoabstime(
  	struct timeval  *tvp)
  {
  	uint64_t        result, usresult;
  
  	clock_interval_to_absolutetime_interval(
  		tvp->tv_sec, NSEC_PER_SEC, &result);
  	clock_interval_to_absolutetime_interval(
  		tvp->tv_usec, NSEC_PER_USEC, &usresult);
  
  	return result + usresult;
  }
  
  uint64_t
  tstoabstime(struct timespec *ts)
  {
  	uint64_t abstime_s, abstime_ns;
  	clock_interval_to_absolutetime_interval(ts->tv_sec, NSEC_PER_SEC, &abstime_s);
  	clock_interval_to_absolutetime_interval(ts->tv_nsec, 1, &abstime_ns);
  	return abstime_s + abstime_ns;
  }
  
  #if NETWORKING
  /*
   * ratecheck(): simple time-based rate-limit checking.
   */
  int
  ratecheck(struct timeval *lasttime, const struct timeval *mininterval)
  {
  	struct timeval tv, delta;
  	int rv = 0;
  
  	net_uptime2timeval(&tv);
  	delta = tv;
  	timevalsub(&delta, lasttime);
  
  	/*
  	 * check for 0,0 is so that the message will be seen at least once,
  	 * even if interval is huge.
  	 */
  	if (timevalcmp(&delta, mininterval, >=) ||
  	    (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) {
  		*lasttime = tv;
  		rv = 1;
  	}
  
  	return rv;
  }
  
  /*
   * ppsratecheck(): packets (or events) per second limitation.
   */
  int
  ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps)
  {
  	struct timeval tv, delta;
  	int rv;
  
  	net_uptime2timeval(&tv);
  
  	timersub(&tv, lasttime, &delta);
  
  	/*
  	 * Check for 0,0 so that the message will be seen at least once.
  	 * If more than one second has passed since the last update of
  	 * lasttime, reset the counter.
  	 *
  	 * we do increment *curpps even in *curpps < maxpps case, as some may
  	 * try to use *curpps for stat purposes as well.
  	 */
  	if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) ||
  	    delta.tv_sec >= 1) {
  		*lasttime = tv;
  		*curpps = 0;
  		rv = 1;
  	} else if (maxpps < 0) {
  		rv = 1;
  	} else if (*curpps < maxpps) {
  		rv = 1;
  	} else {
  		rv = 0;
  	}
  
  #if 1 /* DIAGNOSTIC? */
  	/* be careful about wrap-around */
  	if (*curpps + 1 > 0) {
  		*curpps = *curpps + 1;
  	}
  #else
  	/*
  	 * assume that there's not too many calls to this function.
  	 * not sure if the assumption holds, as it depends on *caller's*
  	 * behavior, not the behavior of this function.
  	 * IMHO it is wrong to make assumption on the caller's behavior,
  	 * so the above #if is #if 1, not #ifdef DIAGNOSTIC.
  	 */
  	*curpps = *curpps + 1;
  #endif
  
  	return rv;
  }
  #endif /* NETWORKING */
  
  void
  time_zone_slock_init(void)
  {
  	/* allocate lock group attribute and group */
  	tz_slock_grp_attr = lck_grp_attr_alloc_init();
  
  	tz_slock_grp =  lck_grp_alloc_init("tzlock", tz_slock_grp_attr);
  
  	/* Allocate lock attribute */
  	tz_slock_attr = lck_attr_alloc_init();
  
  	/* Allocate the spin lock */
  	tz_slock = lck_spin_alloc_init(tz_slock_grp, tz_slock_attr);
  }
  
  int
  __mach_bridge_remote_time(__unused struct proc *p, struct __mach_bridge_remote_time_args *mbrt_args, uint64_t *retval)
  {
  	*retval = mach_bridge_remote_time(mbrt_args->local_timestamp);
  	return 0;
  }
  