1 /* $NetBSD: clock.h,v 1.3 2014/11/17 17:11:29 christos Exp $ */
4 * Copyright (c) 1996 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
35 /* Some handy constants. */
36 #define SECS_PER_MINUTE 60
37 #define SECS_PER_HOUR 3600
38 #define SECS_PER_DAY 86400
39 #define DAYS_PER_COMMON_YEAR 365
40 #define DAYS_PER_LEAP_YEAR 366
41 #define SECS_PER_COMMON_YEAR (SECS_PER_DAY * DAYS_PER_COMMON_YEAR)
42 #define SECS_PER_LEAP_YEAR (SECS_PER_DAY * DAYS_PER_LEAP_YEAR)
44 /* Traditional POSIX base year */
45 #define POSIX_BASE_YEAR 1970
47 /* Some handy functions */
54 case 4: case 6: case 9: case 11:
56 case 1: case 3: case 5: case 7: case 8: case 10: case 12:
64 * This inline avoids some unnecessary modulo operations
65 * as compared with the usual macro:
66 * ( ((year % 4) == 0 &&
67 * (year % 100) != 0) ||
68 * ((year % 400) == 0) )
69 * It is otherwise equivalent.
72 is_leap_year(uint64_t year
)
77 if (__predict_false((year
% 100) != 0))
80 return __predict_false((year
% 400) == 0);
84 days_per_year(uint64_t year
)
86 return is_leap_year(year
) ? DAYS_PER_LEAP_YEAR
: DAYS_PER_COMMON_YEAR
;
89 #endif /* _SYS_CLOCK_H_ */