mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-22 10:26:20 +00:00
60 lines
1.7 KiB
C
60 lines
1.7 KiB
C
/* Convert double to timespec.
|
|
|
|
Copyright (C) 2011-2014 Free Software Foundation, Inc.
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
|
|
|
/* written by Paul Eggert */
|
|
|
|
/* Convert the double value SEC to a struct timespec. Round toward
|
|
positive infinity. On overflow, return an extremal value. */
|
|
|
|
#include <config.h>
|
|
|
|
#include "timespec.h"
|
|
|
|
#include "intprops.h"
|
|
|
|
struct timespec
|
|
dtotimespec (double sec)
|
|
{
|
|
double min_representable = TYPE_MINIMUM (time_t);
|
|
double max_representable =
|
|
((TYPE_MAXIMUM (time_t) * (double) TIMESPEC_RESOLUTION
|
|
+ (TIMESPEC_RESOLUTION - 1))
|
|
/ TIMESPEC_RESOLUTION);
|
|
|
|
if (! (min_representable < sec))
|
|
return make_timespec (TYPE_MINIMUM (time_t), 0);
|
|
else if (! (sec < max_representable))
|
|
return make_timespec (TYPE_MAXIMUM (time_t), TIMESPEC_RESOLUTION - 1);
|
|
else
|
|
{
|
|
time_t s = sec;
|
|
double frac = TIMESPEC_RESOLUTION * (sec - s);
|
|
long ns = frac;
|
|
ns += ns < frac;
|
|
s += ns / TIMESPEC_RESOLUTION;
|
|
ns %= TIMESPEC_RESOLUTION;
|
|
|
|
if (ns < 0)
|
|
{
|
|
s--;
|
|
ns += TIMESPEC_RESOLUTION;
|
|
}
|
|
|
|
return make_timespec (s, ns);
|
|
}
|
|
}
|