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38 lines
2.4 KiB
C
38 lines
2.4 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright 2022 Justine Alexandra Roberts Tunney │
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│ │
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│ Permission to use, copy, modify, and/or distribute this software for │
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│ any purpose with or without fee is hereby granted, provided that the │
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│ above copyright notice and this permission notice appear in all copies. │
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│ │
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│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
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│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
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│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
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│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
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│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
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│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
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│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
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│ PERFORMANCE OF THIS SOFTWARE. │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/calls/struct/timeval.h"
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/**
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* Reduces `ts` from 1e-9 to 1e-6 granularity w/ ceil rounding.
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*
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* This function uses ceiling rounding. For example, if `ts` is one
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* nanosecond, then one microsecond will be returned. Ceil rounding
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* is needed by many interfaces, e.g. setitimer(), because the zero
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* timestamp has a special meaning.
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*
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* @return microseconds since epoch
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* @see _timespec_tomicros()
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*/
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struct timeval _timespec_totimeval(struct timespec ts) {
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if (ts.tv_nsec < 1000000000 - 999) {
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return (struct timeval){ts.tv_sec, (ts.tv_nsec + 999) / 1000};
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} else {
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return (struct timeval){ts.tv_sec + 1, 0};
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}
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}
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