1// Copyright (c) 2014 Google Inc. (contributed by Remy Blank <rblank@google.com>)
2// Copyright (c) 2013-2014 Sandstorm Development Group, Inc. and contributors
3// Licensed under the MIT License:
4//
5// Permission is hereby granted, free of charge, to any person obtaining a copy
6// of this software and associated documentation files (the "Software"), to deal
7// in the Software without restriction, including without limitation the rights
8// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
9// copies of the Software, and to permit persons to whom the Software is
10// furnished to do so, subject to the following conditions:
11//
12// The above copyright notice and this permission notice shall be included in
13// all copies or substantial portions of the Software.
14//
15// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21// THE SOFTWARE.
22
23#pragma once
24
25#if defined(__GNUC__) && !KJ_HEADER_WARNINGS
26#pragma GCC system_header
27#endif
28
29#include "units.h"
30#include <inttypes.h>
31
32namespace kj {
33namespace _ { // private
34
35class NanosecondLabel;
36class TimeLabel;
37class DateLabel;
38
39} // namespace _ (private)
40
41using Duration = Quantity<int64_t, _::NanosecondLabel>;
42// A time value, in nanoseconds.
43
44constexpr Duration NANOSECONDS = unit<Duration>();
45constexpr Duration MICROSECONDS = 1000 * NANOSECONDS;
46constexpr Duration MILLISECONDS = 1000 * MICROSECONDS;
47constexpr Duration SECONDS = 1000 * MILLISECONDS;
48constexpr Duration MINUTES = 60 * SECONDS;
49constexpr Duration HOURS = 60 * MINUTES;
50constexpr Duration DAYS = 24 * HOURS;
51
52using TimePoint = Absolute<Duration, _::TimeLabel>;
53// An absolute time measured by some particular instance of `Timer`. `Time`s from two different
54// `Timer`s may be measured from different origins and so are not necessarily compatible.
55
56using Date = Absolute<Duration, _::DateLabel>;
57// A point in real-world time, measured relative to the Unix epoch (Jan 1, 1970 00:00:00 UTC).
58
59constexpr Date UNIX_EPOCH = origin<Date>();
60// The `Date` representing Jan 1, 1970 00:00:00 UTC.
61
62class Clock {
63 // Interface to read the current date and time.
64public:
65 virtual Date now() const = 0;
66};
67
68const Clock& nullClock();
69// A clock which always returns UNIX_EPOCH as the current time. Useful when you don't care about
70// time.
71
72} // namespace kj
73