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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
* Copyright 2016 Joyent, Inc.
*/
#include <sys/types.h>
#include <time.h>
#include <errno.h>
/*
* This function is blatently stolen from the kernel.
* See the dissertation in the comments preceding the
* hrt2ts() function in:
* uts/common/os/timers.c
*/
void
hrt2ts(hrtime_t hrt, timespec_t *tsp)
{
#if defined(__amd64)
tsp->tv_sec = hrt / NANOSEC;
tsp->tv_nsec = hrt % NANOSEC;
#else
uint32_t sec, nsec, tmp;
tmp = (uint32_t)(hrt >> 30);
sec = tmp - (tmp >> 2);
sec = tmp - (sec >> 5);
sec = tmp + (sec >> 1);
sec = tmp - (sec >> 6) + 7;
sec = tmp - (sec >> 3);
sec = tmp + (sec >> 1);
sec = tmp + (sec >> 3);
sec = tmp + (sec >> 4);
tmp = (sec << 7) - sec - sec - sec;
tmp = (tmp << 7) - tmp - tmp - tmp;
tmp = (tmp << 7) - tmp - tmp - tmp;
nsec = (uint32_t)hrt - (tmp << 9);
while (nsec >= NANOSEC) {
nsec -= NANOSEC;
sec++;
}
tsp->tv_sec = (time_t)sec;
tsp->tv_nsec = nsec;
#endif /* defined(__amd64) */
}
/*
* Convert absolute time to relative time.
* All *timedwait() system call traps expect relative time.
*/
void
abstime_to_reltime(clockid_t clock_id, const timespec_t *abstime,
timespec_t *reltime)
{
extern int __clock_gettime(clockid_t, timespec_t *);
timespec_t now;
if (clock_id == CLOCK_HIGHRES)
hrt2ts(gethrtime(), &now);
else
(void) __clock_gettime(clock_id, &now);
if (abstime->tv_nsec >= now.tv_nsec) {
reltime->tv_sec = abstime->tv_sec - now.tv_sec;
reltime->tv_nsec = abstime->tv_nsec - now.tv_nsec;
} else {
reltime->tv_sec = abstime->tv_sec - now.tv_sec - 1;
reltime->tv_nsec = abstime->tv_nsec - now.tv_nsec + NANOSEC;
}
/*
* If the absolute time has already passed,
* just set the relative time to zero.
*/
if (reltime->tv_sec < 0) {
reltime->tv_sec = 0;
reltime->tv_nsec = 0;
}
/*
* If the specified absolute time has a bad nanoseconds value,
* assign it to the relative time value. If the interface
* attempts to sleep, the bad value will be detected then.
* The SUSV3 Posix spec is very clear that such detection
* should not happen until an attempt to sleep is made.
*/
if ((ulong_t)abstime->tv_nsec >= NANOSEC)
reltime->tv_nsec = abstime->tv_nsec;
}
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