src/basic/time-util.h

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 #pragma once
   4
   5 /***
   6   This file is part of systemd.
   7
   8   Copyright 2010 Lennart Poettering
   9
  10   systemd is free software; you can redistribute it and/or modify it
  11   under the terms of the GNU Lesser General Public License as published by
  12   the Free Software Foundation; either version 2.1 of the License, or
  13   (at your option) any later version.
  14
  15   systemd is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   Lesser General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  22 ***/
  23
  24 #include <inttypes.h>
  25 #include <stdbool.h>
  26 #include <stddef.h>
  27 #include <stdint.h>
  28 #include <stdio.h>
  29 #include <time.h>
  30
  31 typedef uint64_t usec_t;
  32 typedef uint64_t nsec_t;
  33
  34 #define NSEC_FMT "%" PRIu64
  35 #define USEC_FMT "%" PRIu64
  36
  37 #include "macro.h"
  38
  39 typedef struct dual_timestamp {
  40         usec_t realtime;
  41         usec_t monotonic;
  42 } dual_timestamp;
  43
  44 #define USEC_INFINITY ((usec_t) -1)
  45 #define NSEC_INFINITY ((nsec_t) -1)
  46
  47 #define MSEC_PER_SEC  1000ULL
  48 #define USEC_PER_SEC  ((usec_t) 1000000ULL)
  49 #define USEC_PER_MSEC ((usec_t) 1000ULL)
  50 #define NSEC_PER_SEC  ((nsec_t) 1000000000ULL)
  51 #define NSEC_PER_MSEC ((nsec_t) 1000000ULL)
  52 #define NSEC_PER_USEC ((nsec_t) 1000ULL)
  53
  54 #define USEC_PER_MINUTE ((usec_t) (60ULL*USEC_PER_SEC))
  55 #define NSEC_PER_MINUTE ((nsec_t) (60ULL*NSEC_PER_SEC))
  56 #define USEC_PER_HOUR ((usec_t) (60ULL*USEC_PER_MINUTE))
  57 #define NSEC_PER_HOUR ((nsec_t) (60ULL*NSEC_PER_MINUTE))
  58 #define USEC_PER_DAY ((usec_t) (24ULL*USEC_PER_HOUR))
  59 #define NSEC_PER_DAY ((nsec_t) (24ULL*NSEC_PER_HOUR))
  60 #define USEC_PER_WEEK ((usec_t) (7ULL*USEC_PER_DAY))
  61 #define NSEC_PER_WEEK ((nsec_t) (7ULL*NSEC_PER_DAY))
  62 #define USEC_PER_MONTH ((usec_t) (2629800ULL*USEC_PER_SEC))
  63 #define NSEC_PER_MONTH ((nsec_t) (2629800ULL*NSEC_PER_SEC))
  64 #define USEC_PER_YEAR ((usec_t) (31557600ULL*USEC_PER_SEC))
  65 #define NSEC_PER_YEAR ((nsec_t) (31557600ULL*NSEC_PER_SEC))
  66
  67 #define FORMAT_TIMESTAMP_MAX ((4*4+1)+11+9+4+1) /* weekdays can be unicode */
  68 #define FORMAT_TIMESTAMP_WIDTH 28 /* when outputting, assume this width */
  69 #define FORMAT_TIMESTAMP_RELATIVE_MAX 256
  70 #define FORMAT_TIMESPAN_MAX 64
  71
  72 #define TIME_T_MAX (time_t)((UINTMAX_C(1) << ((sizeof(time_t) << 3) - 1)) - 1)
  73
  74 #define DUAL_TIMESTAMP_NULL ((struct dual_timestamp) { 0ULL, 0ULL })
  75
  76 usec_t now(clockid_t clock);
  77 nsec_t now_nsec(clockid_t clock);
  78
  79 dual_timestamp* dual_timestamp_get(dual_timestamp *ts);
  80 dual_timestamp* dual_timestamp_from_realtime(dual_timestamp *ts, usec_t u);
  81 dual_timestamp* dual_timestamp_from_monotonic(dual_timestamp *ts, usec_t u);
  82 dual_timestamp* dual_timestamp_from_boottime_or_monotonic(dual_timestamp *ts, usec_t u);
  83
  84 static inline bool dual_timestamp_is_set(dual_timestamp *ts) {
  85         return ((ts->realtime > 0 && ts->realtime != USEC_INFINITY) ||
  86                 (ts->monotonic > 0 && ts->monotonic != USEC_INFINITY));
  87 }
  88
  89 usec_t timespec_load(const struct timespec *ts) _pure_;
  90 struct timespec *timespec_store(struct timespec *ts, usec_t u);
  91
  92 usec_t timeval_load(const struct timeval *tv) _pure_;
  93 struct timeval *timeval_store(struct timeval *tv, usec_t u);
  94
  95 char *format_timestamp(char *buf, size_t l, usec_t t);
  96 char *format_timestamp_utc(char *buf, size_t l, usec_t t);
  97 char *format_timestamp_us(char *buf, size_t l, usec_t t);
  98 char *format_timestamp_us_utc(char *buf, size_t l, usec_t t);
  99 char *format_timestamp_relative(char *buf, size_t l, usec_t t);
 100 char *format_timespan(char *buf, size_t l, usec_t t, usec_t accuracy);
 101
 102 void dual_timestamp_serialize(FILE *f, const char *name, dual_timestamp *t);
 103 int dual_timestamp_deserialize(const char *value, dual_timestamp *t);
 104
 105 int parse_timestamp(const char *t, usec_t *usec);
 106
 107 int parse_sec(const char *t, usec_t *usec);
 108 int parse_time(const char *t, usec_t *usec, usec_t default_unit);
 109 int parse_nsec(const char *t, nsec_t *nsec);
 110
 111 bool ntp_synced(void);
 112
 113 int get_timezones(char ***l);
 114 bool timezone_is_valid(const char *name);
 115
 116 clockid_t clock_boottime_or_monotonic(void);
 117
 118 #define xstrftime(buf, fmt, tm) \
 119         assert_message_se(strftime(buf, ELEMENTSOF(buf), fmt, tm) > 0, \
 120                           "xstrftime: " #buf "[] must be big enough")
 121
 122 int get_timezone(char **timezone);
 123
 124 time_t mktime_or_timegm(struct tm *tm, bool utc);
 125 struct tm *localtime_or_gmtime_r(const time_t *t, struct tm *tm, bool utc);
 126
 127 unsigned long usec_to_jiffies(usec_t usec);
 128
 129 static inline usec_t usec_add(usec_t a, usec_t b) {
 130         usec_t c;
 131
 132         /* Adds two time values, and makes sure USEC_INFINITY as input results as USEC_INFINITY in output, and doesn't
 133          * overflow. */
 134
 135         c = a + b;
 136         if (c < a || c < b) /* overflow check */
 137                 return USEC_INFINITY;
 138
 139         return c;
 140 }
 141
 142 static inline usec_t usec_sub(usec_t timestamp, int64_t delta) {
 143         if (delta < 0)
 144                 return usec_add(timestamp, (usec_t) (-delta));
 145
 146         if (timestamp == USEC_INFINITY) /* Make sure infinity doesn't degrade */
 147                 return USEC_INFINITY;
 148
 149         if (timestamp < (usec_t) delta)
 150                 return 0;
 151
 152         return timestamp - delta;
 153 }