1 /*
2  * Copyright (C) 2008 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #ifndef _SYS_TIME_H_
30 #define _SYS_TIME_H_
31 
32 #include <sys/cdefs.h>
33 #include <sys/types.h>
34 #include <linux/time.h>
35 
36 /* POSIX says <sys/time.h> gets you most of <sys/select.h> and may get you all of it. */
37 #include <sys/select.h>
38 
39 __BEGIN_DECLS
40 
41 int gettimeofday(struct timeval* _Nullable __tv, struct timezone* _Nullable __tz);
42 int settimeofday(const struct timeval* _Nullable __tv, const struct timezone* _Nullable __tz);
43 
44 int getitimer(int __which, struct itimerval* _Nonnull __current_value);
45 int setitimer(int __which, const struct itimerval* _Nonnull __new_value, struct itimerval* _Nullable __old_value);
46 
47 int utimes(const char* _Nonnull __path, const struct timeval __times[_Nullable 2]);
48 
49 #if defined(__USE_BSD)
50 
51 #if __BIONIC_AVAILABILITY_GUARD(26)
52 int futimes(int __fd, const struct timeval __times[_Nullable 2]) __INTRODUCED_IN(26);
53 int lutimes(const char* _Nonnull __path, const struct timeval __times[_Nullable 2]) __INTRODUCED_IN(26);
54 #endif /* __BIONIC_AVAILABILITY_GUARD(26) */
55 
56 #endif
57 
58 #if defined(__USE_GNU)
59 /**
60  * [futimesat(2)](https://man7.org/linux/man-pages/man2/futimesat.2.html) sets
61  * file timestamps.
62  *
63  * Note: Linux supports `__path` being NULL (in which case `__dir_fd` need not
64  * be a directory), allowing futimensat() to be implemented with utimensat().
65  * Most callers should just use utimensat() directly, especially on Android
66  * where utimensat() has been available for longer than futimesat().
67  *
68  * Returns 0 on success and -1 and sets `errno` on failure.
69  *
70  * Available since API level 26.
71  */
72 
73 #if __BIONIC_AVAILABILITY_GUARD(26)
74 int futimesat(int __dir_fd, const char* __BIONIC_COMPLICATED_NULLNESS __path, const struct timeval __times[_Nullable 2]) __INTRODUCED_IN(26);
75 #endif /* __BIONIC_AVAILABILITY_GUARD(26) */
76 
77 #endif
78 
79 #define timerclear(a)   \
80         ((a)->tv_sec = (a)->tv_usec = 0)
81 
82 #define timerisset(a)    \
83         ((a)->tv_sec != 0 || (a)->tv_usec != 0)
84 
85 #define timercmp(a, b, op)               \
86         ((a)->tv_sec == (b)->tv_sec      \
87         ? (a)->tv_usec op (b)->tv_usec   \
88         : (a)->tv_sec op (b)->tv_sec)
89 
90 #define timeradd(a, b, res)                           \
91     do {                                              \
92         (res)->tv_sec  = (a)->tv_sec  + (b)->tv_sec;  \
93         (res)->tv_usec = (a)->tv_usec + (b)->tv_usec; \
94         if ((res)->tv_usec >= 1000000) {              \
95             (res)->tv_usec -= 1000000;                \
96             (res)->tv_sec  += 1;                      \
97         }                                             \
98     } while (0)
99 
100 #define timersub(a, b, res)                           \
101     do {                                              \
102         (res)->tv_sec  = (a)->tv_sec  - (b)->tv_sec;  \
103         (res)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
104         if ((res)->tv_usec < 0) {                     \
105             (res)->tv_usec += 1000000;                \
106             (res)->tv_sec  -= 1;                      \
107         }                                             \
108     } while (0)
109 
110 #define TIMEVAL_TO_TIMESPEC(tv, ts) {     \
111     (ts)->tv_sec = (tv)->tv_sec;          \
112     (ts)->tv_nsec = (tv)->tv_usec * 1000; \
113 }
114 #define TIMESPEC_TO_TIMEVAL(tv, ts) {     \
115     (tv)->tv_sec = (ts)->tv_sec;          \
116     (tv)->tv_usec = (ts)->tv_nsec / 1000; \
117 }
118 
119 __END_DECLS
120 
121 #endif
122