1 /* Convert double to timespec.
3 Copyright (C) 2011-2013 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
18 /* written by Paul Eggert */
20 /* Convert the double value SEC to a struct timespec. Round toward
21 positive infinity. On overflow, return an extremal value. */
30 dtotimespec (double sec)
32 enum { BILLION = 1000 * 1000 * 1000 };
33 double min_representable = TYPE_MINIMUM (time_t);
34 double max_representable =
35 ((TYPE_MAXIMUM (time_t) * (double) BILLION + (BILLION - 1))
39 if (! (min_representable < sec))
41 r.tv_sec = TYPE_MINIMUM (time_t);
44 else if (! (sec < max_representable))
46 r.tv_sec = TYPE_MAXIMUM (time_t);
47 r.tv_nsec = BILLION - 1;
52 double frac = BILLION * (sec - s);