src/basic/time-util.h

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