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 // Returns a human-readable time string which prints every nanosecond while trying to limit the
39 // number of trailing zeros. Prints using the largest human readable unit up to a second.
40 // e.g. "1ms", "1.000000001s", "1.001us"
41 std::string PrettyDuration(uint64_t nano_duration, size_t max_fraction_digits = 3);
42
43 // Format a nanosecond time to specified units.
44 std::string FormatDuration(uint64_t nano_duration, TimeUnit time_unit,
45 size_t max_fraction_digits);
46
47 // Get the appropriate unit for a nanosecond duration.
48 TimeUnit GetAppropriateTimeUnit(uint64_t nano_duration);
49
50 // Get the divisor to convert from a nanoseconds to a time unit.
51 uint64_t GetNsToTimeUnitDivisor(TimeUnit time_unit);
52
53 // Returns the current date in ISO yyyy-mm-dd hh:mm:ss format.
54 std::string GetIsoDate();
55
56 // Returns the monotonic time since some unspecified starting point in milliseconds.
57 uint64_t MilliTime();
58
59 // Returns the monotonic time since some unspecified starting point in microseconds.
60 uint64_t MicroTime();
61
62 // Returns the monotonic time since some unspecified starting point in nanoseconds.
63 uint64_t NanoTime();
64
65 // Returns the thread-specific CPU-time clock in nanoseconds or -1 if unavailable.
66 uint64_t ThreadCpuNanoTime();
67
68 // Returns the process CPU-time clock in nanoseconds or -1 if unavailable.
69 uint64_t ProcessCpuNanoTime();
70
71 // Converts the given number of nanoseconds to milliseconds.
NsToMs(uint64_t ns)72 static constexpr inline uint64_t NsToMs(uint64_t ns) {
73 return ns / 1000 / 1000;
74 }
75
76 // Converts the given number of milliseconds to nanoseconds
MsToNs(uint64_t ms)77 static constexpr inline uint64_t MsToNs(uint64_t ms) {
78 return ms * 1000 * 1000;
79 }
80
81 // Converts the given number of milliseconds to microseconds
MsToUs(uint64_t ms)82 static constexpr inline uint64_t MsToUs(uint64_t ms) {
83 return ms * 1000;
84 }
85
UsToNs(uint64_t us)86 static constexpr inline uint64_t UsToNs(uint64_t us) {
87 return us * 1000;
88 }
89
90 #if defined(__APPLE__)
91 #ifndef CLOCK_REALTIME
92 // No clocks to specify on OS/X < 10.12, fake value to pass to routines that require a clock.
93 #define CLOCK_REALTIME 0xebadf00d
94 #endif
95 #endif
96
97 // Sleep for the given number of nanoseconds, a bad way to handle contention.
98 void NanoSleep(uint64_t ns);
99
100 // Initialize a timespec to either a relative time (ms,ns), or to the absolute
101 // time corresponding to the indicated clock value plus the supplied offset.
102 void InitTimeSpec(bool absolute, int clock, int64_t ms, int32_t ns, timespec* ts);
103
104 } // namespace art
105
106 #endif // ART_LIBARTBASE_BASE_TIME_UTILS_H_
107