xref: /netbsd-src/sys/external/bsd/drm2/include/linux/time.h (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: time.h,v 1.2 2014/03/18 18:20:43 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Taylor R. Campbell.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
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.
18  *
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.
30  */
31 
32 #ifndef _LINUX_TIME_H_
33 #define _LINUX_TIME_H_
34 
35 #include <sys/time.h>
36 
37 /*
38  * XXX get_seconds as implemented by Linux is a Y2038 bug waiting to
39  * happen on 32-bit systems because it returns unsigned long.  Some
40  * callers in Linux (implicitly) convert the result to time_t, though.
41  * We'll pretend get_seconds returns time_t and make sure all our
42  * callers treat it as if it did.
43  */
44 
45 static inline time_t
46 get_seconds(void)
47 {
48 	return time_second;
49 }
50 
51 static inline void
52 getrawmonotonic(struct timespec *ts)
53 {
54 	getnanouptime(ts);
55 }
56 
57 static inline bool
58 timespec_valid(const struct timespec *ts)
59 {
60 	if (ts->tv_sec < 0)
61 		return false;
62 	if (1000000000L <= ts->tv_nsec)
63 		return false;
64 	return true;
65 }
66 
67 static inline struct timespec
68 ns_to_timespec(const int64_t nsec)
69 {
70 	struct timespec ts;
71 
72 	ts.tv_sec = (nsec / 1000000000L);
73 	ts.tv_nsec = (nsec % 1000000000L);
74 	if (ts.tv_nsec < 0) {
75 		ts.tv_sec -= 1;
76 		ts.tv_nsec += 1000000000L;
77 	}
78 
79 	return ts;
80 }
81 
82 static inline int64_t
83 timespec_to_ns(const struct timespec *ts)
84 {
85 	return (((int64_t)ts->tv_sec * 1000000000LL) + ts->tv_nsec);
86 }
87 
88 static inline struct timespec
89 timespec_sub(struct timespec a, struct timespec b)
90 {
91 	struct timespec d;
92 
93 	timespecsub(&a, &b, &d);
94 
95 	return d;
96 }
97 
98 static inline void
99 set_normalized_timespec(struct timespec *ts, time_t sec, int64_t nsec)
100 {
101 	while (nsec >= 1000000000L) {
102 		nsec -= 1000000000L;
103 		sec += 1;
104 	}
105 	while (nsec < 0) {
106 		nsec += 1000000000L;
107 		sec -= 1;
108 	}
109 	ts->tv_sec = sec;
110 	ts->tv_nsec = nsec;
111 }
112 
113 #endif  /* _LINUX_TIME_H_ */
114