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diff --git a/support/dtotimespec.c b/support/dtotimespec.c
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+/* Convert double to timespec.
+ Copyright (C) 2011-2023 Free Software Foundation, Inc.
+ This file is part of the GNU C Library and is also part of gnulib.
+ Patches to this file should be submitted to both projects.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+/* Convert the double value SEC to a struct timespec. Round toward
+ positive infinity. On overflow, return an extremal value. */
+
+#include <support/timespec.h>
+#include <intprops.h>
+
+struct timespec
+dtotimespec (double sec)
+{
+ if (sec <= TYPE_MINIMUM (time_t))
+ 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);
+ }
+}