1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #ifndef ART_LIBARTBASE_BASE_TIME_UTILS_H_
18 #define ART_LIBARTBASE_BASE_TIME_UTILS_H_
19
20 #ifdef _WIN32
21 #include <stdio.h> // Needed for correct macro definitions.
22 #endif
23
24 #include <time.h>
25
26 #include <cstdint>
27 #include <string>
28
29 namespace art {
30
31 enum TimeUnit {
32 kTimeUnitNanosecond,
33 kTimeUnitMicrosecond,
34 kTimeUnitMillisecond,
35 kTimeUnitSecond,
36 };
37
38 // Constants for common time periods.
39 constexpr unsigned int kOneMinuteInSeconds = 60;
40 constexpr unsigned int kOneHourInSeconds = 60 * kOneMinuteInSeconds;
41
42 // Returns a human-readable time string which prints every nanosecond while trying to limit the
43 // number of trailing zeros. Prints using the largest human readable unit up to a second.
44 // e.g. "1ms", "1.000000001s", "1.001us"
45 std::string PrettyDuration(uint64_t nano_duration, size_t max_fraction_digits = 3);
46
47 // Format a nanosecond time to specified units.
48 std::string FormatDuration(uint64_t nano_duration, TimeUnit time_unit,
49 size_t max_fraction_digits);
50
51 // Get the appropriate unit for a nanosecond duration.
52 TimeUnit GetAppropriateTimeUnit(uint64_t nano_duration);
53
54 // Get the divisor to convert from a nanoseconds to a time unit.
55 uint64_t GetNsToTimeUnitDivisor(TimeUnit time_unit);
56
57 // Returns the current date in ISO yyyy-mm-dd hh:mm:ss format.
58 std::string GetIsoDate();
59
60 // Returns the monotonic time since some unspecified starting point in milliseconds.
61 uint64_t MilliTime();
62
63 // Returns the monotonic time since some unspecified starting point in microseconds.
64 uint64_t MicroTime();
65
66 // Returns the monotonic time since some unspecified starting point in nanoseconds.
67 uint64_t NanoTime();
68
69 // Returns the thread-specific CPU-time clock in nanoseconds or -1 if unavailable.
70 uint64_t ThreadCpuNanoTime();
71
72 // Returns the process CPU-time clock in nanoseconds or -1 if unavailable.
73 uint64_t ProcessCpuNanoTime();
74
75 // Converts the given number of nanoseconds to milliseconds.
NsToMs(uint64_t ns)76 static constexpr uint64_t NsToMs(uint64_t ns) {
77 return ns / 1000 / 1000;
78 }
79
80 // Converts the given number of nanoseconds to microseconds.
NsToUs(uint64_t ns)81 static constexpr uint64_t NsToUs(uint64_t ns) {
82 return ns / 1000;
83 }
84
85 // Converts the given number of milliseconds to nanoseconds
MsToNs(uint64_t ms)86 static constexpr uint64_t MsToNs(uint64_t ms) {
87 return ms * 1000 * 1000;
88 }
89
90 // Converts the given number of milliseconds to microseconds
MsToUs(uint64_t ms)91 static constexpr uint64_t MsToUs(uint64_t ms) {
92 return ms * 1000;
93 }
94
UsToNs(uint64_t us)95 static constexpr uint64_t UsToNs(uint64_t us) {
96 return us * 1000;
97 }
98
SecondsToMs(uint64_t seconds)99 static constexpr uint64_t SecondsToMs(uint64_t seconds) {
100 return seconds * 1000;
101 }
102
SaturatedTimeT(int64_t secs)103 static constexpr time_t SaturatedTimeT(int64_t secs) {
104 if (sizeof(time_t) < sizeof(int64_t)) {
105 return static_cast<time_t>(std::min(secs,
106 static_cast<int64_t>(std::numeric_limits<time_t>::max())));
107 } else {
108 return secs;
109 }
110 }
111
112 #if defined(__APPLE__)
113 #ifndef CLOCK_REALTIME
114 // No clocks to specify on OS/X < 10.12, fake value to pass to routines that require a clock.
115 #define CLOCK_REALTIME 0xebadf00d
116 #endif
117 #endif
118
119 // Sleep for the given number of nanoseconds, a bad way to handle contention.
120 void NanoSleep(uint64_t ns);
121
122 // Initialize a timespec to either a relative time (ms,ns), or to the absolute
123 // time corresponding to the indicated clock value plus the supplied offset.
124 void InitTimeSpec(bool absolute, int clock, int64_t ms, int32_t ns, timespec* ts);
125
126 } // namespace art
127
128 #endif // ART_LIBARTBASE_BASE_TIME_UTILS_H_
129