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+/* Convert double to timespec.
+
+ Copyright (C) 2011-2020 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 <https://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)
+{
+ if (! (TYPE_MINIMUM (time_t) < sec))
+ return make_timespec (TYPE_MINIMUM (time_t), 0);
+ else if (! (sec < 1.0 + TYPE_MAXIMUM (time_t)))
+ return make_timespec (TYPE_MAXIMUM (time_t), TIMESPEC_HZ - 1);
+ else
+ {
+ time_t s = sec;
+ double frac = TIMESPEC_HZ * (sec - s);
+ long ns = frac;
+ ns += ns < frac;
+ s += ns / TIMESPEC_HZ;
+ ns %= TIMESPEC_HZ;
+
+ if (ns < 0)
+ {
+ s--;
+ ns += TIMESPEC_HZ;
+ }
+
+ return make_timespec (s, ns);
+ }
+}