1/* Copyright (C) 1991-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#ifndef _SYS_TIME_H
19#define _SYS_TIME_H 1
20
21#include <features.h>
22
23#include <bits/types.h>
24#include <bits/types/time_t.h>
25#include <bits/types/struct_timeval.h>
26
27#ifndef __suseconds_t_defined
28typedef __suseconds_t suseconds_t;
29# define __suseconds_t_defined
30#endif
31
32#include <sys/select.h>
33
34__BEGIN_DECLS
35
36#ifdef __USE_GNU
37/* Macros for converting between `struct timeval' and `struct timespec'. */
38# define TIMEVAL_TO_TIMESPEC(tv, ts) { \
39 (ts)->tv_sec = (tv)->tv_sec; \
40 (ts)->tv_nsec = (tv)->tv_usec * 1000; \
41}
42# define TIMESPEC_TO_TIMEVAL(tv, ts) { \
43 (tv)->tv_sec = (ts)->tv_sec; \
44 (tv)->tv_usec = (ts)->tv_nsec / 1000; \
45}
46#endif
47
48
49#ifdef __USE_MISC
50/* Structure crudely representing a timezone.
51 This is obsolete and should never be used. */
52struct timezone
53 {
54 int tz_minuteswest; /* Minutes west of GMT. */
55 int tz_dsttime; /* Nonzero if DST is ever in effect. */
56 };
57#endif
58
59/* Get the current time of day, putting it into *TV.
60 If TZ is not null, *TZ must be a struct timezone, and both fields
61 will be set to zero.
62 Calling this function with a non-null TZ is obsolete;
63 use localtime etc. instead.
64 This function itself is semi-obsolete;
65 most callers should use time or clock_gettime instead. */
66extern int gettimeofday (struct timeval *__restrict __tv,
67 void *__restrict __tz) __THROW __nonnull ((1));
68
69#ifdef __USE_MISC
70/* Set the current time of day and timezone information.
71 This call is restricted to the super-user.
72 Setting the timezone in this way is obsolete, but we don't yet
73 warn about it because it still has some uses for which there is
74 no alternative. */
75extern int settimeofday (const struct timeval *__tv,
76 const struct timezone *__tz)
77 __THROW;
78
79/* Adjust the current time of day by the amount in DELTA.
80 If OLDDELTA is not NULL, it is filled in with the amount
81 of time adjustment remaining to be done from the last `adjtime' call.
82 This call is restricted to the super-user. */
83extern int adjtime (const struct timeval *__delta,
84 struct timeval *__olddelta) __THROW;
85#endif
86
87
88/* Values for the first argument to `getitimer' and `setitimer'. */
89enum __itimer_which
90 {
91 /* Timers run in real time. */
92 ITIMER_REAL = 0,
93#define ITIMER_REAL ITIMER_REAL
94 /* Timers run only when the process is executing. */
95 ITIMER_VIRTUAL = 1,
96#define ITIMER_VIRTUAL ITIMER_VIRTUAL
97 /* Timers run when the process is executing and when
98 the system is executing on behalf of the process. */
99 ITIMER_PROF = 2
100#define ITIMER_PROF ITIMER_PROF
101 };
102
103/* Type of the second argument to `getitimer' and
104 the second and third arguments `setitimer'. */
105struct itimerval
106 {
107 /* Value to put into `it_value' when the timer expires. */
108 struct timeval it_interval;
109 /* Time to the next timer expiration. */
110 struct timeval it_value;
111 };
112
113#if defined __USE_GNU && !defined __cplusplus
114/* Use the nicer parameter type only in GNU mode and not for C++ since the
115 strict C++ rules prevent the automatic promotion. */
116typedef enum __itimer_which __itimer_which_t;
117#else
118typedef int __itimer_which_t;
119#endif
120
121/* Set *VALUE to the current setting of timer WHICH.
122 Return 0 on success, -1 on errors. */
123extern int getitimer (__itimer_which_t __which,
124 struct itimerval *__value) __THROW;
125
126/* Set the timer WHICH to *NEW. If OLD is not NULL,
127 set *OLD to the old value of timer WHICH.
128 Returns 0 on success, -1 on errors. */
129extern int setitimer (__itimer_which_t __which,
130 const struct itimerval *__restrict __new,
131 struct itimerval *__restrict __old) __THROW;
132
133/* Change the access time of FILE to TVP[0] and the modification time of
134 FILE to TVP[1]. If TVP is a null pointer, use the current time instead.
135 Returns 0 on success, -1 on errors. */
136extern int utimes (const char *__file, const struct timeval __tvp[2])
137 __THROW __nonnull ((1));
138
139#ifdef __USE_MISC
140/* Same as `utimes', but does not follow symbolic links. */
141extern int lutimes (const char *__file, const struct timeval __tvp[2])
142 __THROW __nonnull ((1));
143
144/* Same as `utimes', but takes an open file descriptor instead of a name. */
145extern int futimes (int __fd, const struct timeval __tvp[2]) __THROW;
146#endif
147
148#ifdef __USE_GNU
149/* Change the access time of FILE relative to FD to TVP[0] and the
150 modification time of FILE to TVP[1]. If TVP is a null pointer, use
151 the current time instead. Returns 0 on success, -1 on errors. */
152extern int futimesat (int __fd, const char *__file,
153 const struct timeval __tvp[2]) __THROW;
154#endif
155
156
157#ifdef __USE_MISC
158/* Convenience macros for operations on timevals.
159 NOTE: `timercmp' does not work for >= or <=. */
160# define timerisset(tvp) ((tvp)->tv_sec || (tvp)->tv_usec)
161# define timerclear(tvp) ((tvp)->tv_sec = (tvp)->tv_usec = 0)
162# define timercmp(a, b, CMP) \
163 (((a)->tv_sec == (b)->tv_sec) \
164 ? ((a)->tv_usec CMP (b)->tv_usec) \
165 : ((a)->tv_sec CMP (b)->tv_sec))
166# define timeradd(a, b, result) \
167 do { \
168 (result)->tv_sec = (a)->tv_sec + (b)->tv_sec; \
169 (result)->tv_usec = (a)->tv_usec + (b)->tv_usec; \
170 if ((result)->tv_usec >= 1000000) \
171 { \
172 ++(result)->tv_sec; \
173 (result)->tv_usec -= 1000000; \
174 } \
175 } while (0)
176# define timersub(a, b, result) \
177 do { \
178 (result)->tv_sec = (a)->tv_sec - (b)->tv_sec; \
179 (result)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
180 if ((result)->tv_usec < 0) { \
181 --(result)->tv_sec; \
182 (result)->tv_usec += 1000000; \
183 } \
184 } while (0)
185#endif /* Misc. */
186
187__END_DECLS
188
189#endif /* sys/time.h */
190