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/* monotonic time object and functions, for libreswan
*
* Copyright (C) 1998, 1999, 2000 Henry Spencer.
* Copyright (C) 1999, 2000, 2001 Richard Guy Briggs
* Copyright (C) 2017-2019 Andrew Cagney <cagney@gnu.org>
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Library General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <https://www.gnu.org/licenses/lgpl-2.1.txt>.
*
* 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 Library General Public
* License for more details.
*
*/
#ifndef MONOTIME_H
#define MONOTIME_H /* seen it, no need to see it again */
#include <sys/time.h> /* for struct timeval */
#include <stdbool.h> /* for bool */
#include "deltatime.h"
/*
* The time objects are wrapped so that dimensional analysis will be
* enforced by the compiler.
*/
/*
* monotime_t: absolute monotonic time. No discontinuities (except
* for machine sleep?)
*
* - various clocks can jump backwards on UNIX/LINUX; for instance
* when the machine's UTC clock is corrected
*
* - this causes all kinds of problems with timeouts observable in the
* Real World
*
* - this code detects backward jumps and compensates by refusing to
* go backwards
*
* - unfortunately there is no way to detect forward jumps
*
*/
typedef struct { struct timeval mt; } monotime_t;
monotime_t monotime(intmax_t seconds);
#define MONOTIME_EPOCH { { 0, 0 } }
extern const monotime_t monotime_epoch;
bool is_monotime_epoch(monotime_t t);
monotime_t mononow(void);
monotime_t monotime_max(monotime_t l, monotime_t r);
monotime_t monotime_min(monotime_t l, monotime_t r);
monotime_t monotime_add(monotime_t l, deltatime_t r);
monotime_t monotime_sub(monotime_t l, deltatime_t r);
deltatime_t monotime_diff(monotime_t l, monotime_t r);
/* sign(a - b); see timercmp() for hacks origin */
int monotime_sub_sign(monotime_t l, monotime_t r);
#define monotime_cmp(L, OP, R) (monotime_sub_sign(L, R) OP 0)
intmax_t monosecs(monotime_t m);
/* for pthread_cond_timedwait() */
clockid_t monotime_clockid(void);
typedef struct {
/* slightly over size */
char buf[sizeof("-18446744073709551615.1000000")+1/*canary*/]; /* true length ???? */
} monotime_buf;
const char *str_monotime(monotime_t d, monotime_buf *buf);
size_t jam_monotime(struct jambuf *buf, monotime_t d);
#endif
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