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 #include "time_utils.h"
18 
19 #include <inttypes.h>
20 #include <stdio.h>
21 
22 #include <limits>
23 #include <sstream>
24 
25 #include "android-base/stringprintf.h"
26 
27 #include "logging.h"
28 
29 #if defined(__APPLE__)
30 #include <sys/time.h>
31 #endif
32 
33 namespace art {
34 
35 namespace {
36 
37 #if !defined(__linux__)
38 int GetTimeOfDay(struct timeval* tv, struct timezone* tz) {
39 #ifdef _WIN32
40   return mingw_gettimeofday(tv, tz);
41 #else
42   return gettimeofday(tv, tz);
43 #endif
44 }
45 #endif
46 
47 }  // namespace
48 
49 using android::base::StringPrintf;
50 
51 std::string PrettyDuration(uint64_t nano_duration, size_t max_fraction_digits) {
52   if (nano_duration == 0) {
53     return "0";
54   } else {
55     return FormatDuration(nano_duration, GetAppropriateTimeUnit(nano_duration),
56                           max_fraction_digits);
57   }
58 }
59 
60 TimeUnit GetAppropriateTimeUnit(uint64_t nano_duration) {
61   const uint64_t one_sec = 1000 * 1000 * 1000;
62   const uint64_t one_ms  = 1000 * 1000;
63   const uint64_t one_us  = 1000;
64   if (nano_duration >= one_sec) {
65     return kTimeUnitSecond;
66   } else if (nano_duration >= one_ms) {
67     return kTimeUnitMillisecond;
68   } else if (nano_duration >= one_us) {
69     return kTimeUnitMicrosecond;
70   } else {
71     return kTimeUnitNanosecond;
72   }
73 }
74 
75 uint64_t GetNsToTimeUnitDivisor(TimeUnit time_unit) {
76   const uint64_t one_sec = 1000 * 1000 * 1000;
77   const uint64_t one_ms  = 1000 * 1000;
78   const uint64_t one_us  = 1000;
79 
80   switch (time_unit) {
81     case kTimeUnitSecond:
82       return one_sec;
83     case kTimeUnitMillisecond:
84       return one_ms;
85     case kTimeUnitMicrosecond:
86       return one_us;
87     case kTimeUnitNanosecond:
88       return 1;
89   }
90   return 0;
91 }
92 
93 std::string FormatDuration(uint64_t nano_duration, TimeUnit time_unit,
94                            size_t max_fraction_digits) {
95   const char* unit = nullptr;
96   uint64_t divisor = GetNsToTimeUnitDivisor(time_unit);
97   switch (time_unit) {
98     case kTimeUnitSecond:
99       unit = "s";
100       break;
101     case kTimeUnitMillisecond:
102       unit = "ms";
103       break;
104     case kTimeUnitMicrosecond:
105       unit = "us";
106       break;
107     case kTimeUnitNanosecond:
108       unit = "ns";
109       break;
110   }
111   const uint64_t whole_part = nano_duration / divisor;
112   uint64_t fractional_part = nano_duration % divisor;
113   if (fractional_part == 0) {
114     return StringPrintf("%" PRIu64 "%s", whole_part, unit);
115   } else {
116     static constexpr size_t kMaxDigits = 30;
117     size_t avail_digits = kMaxDigits;
118     char fraction_buffer[kMaxDigits];
119     char* ptr = fraction_buffer;
120     uint64_t multiplier = 10;
121     // This infinite loops if fractional part is 0.
122     while (avail_digits > 1 && fractional_part * multiplier < divisor) {
123       multiplier *= 10;
124       *ptr++ = '0';
125       avail_digits--;
126     }
127     snprintf(ptr, avail_digits, "%" PRIu64, fractional_part);
128     fraction_buffer[std::min(kMaxDigits - 1, max_fraction_digits)] = '\0';
129     return StringPrintf("%" PRIu64 ".%s%s", whole_part, fraction_buffer, unit);
130   }
131 }
132 
133 std::string GetIsoDate() {
134   tm tmbuf;
135   int ns;
136 #ifdef _WIN32
137   time_t now = time(nullptr);
138   localtime_s(&tmbuf, &now);
139   ns = 0;
140 #else
141   if (__builtin_available(macOS 10.12, *)) {
142     timespec now;
143     clock_gettime(CLOCK_REALTIME, &now);
144     localtime_r(&now.tv_sec, &tmbuf);
145     ns = now.tv_nsec;
146   } else {
147     time_t now = time(nullptr);
148     localtime_r(&now, &tmbuf);
149     ns = 0;
150   }
151 #endif
152   char zone[16] = {};
153   strftime(zone, sizeof(zone), "%z", &tmbuf);
154   return StringPrintf("%04d-%02d-%02d %02d:%02d:%02d.%09d%s",
155       tmbuf.tm_year + 1900, tmbuf.tm_mon+1, tmbuf.tm_mday,
156       tmbuf.tm_hour, tmbuf.tm_min, tmbuf.tm_sec, ns, zone);
157 }
158 
159 uint64_t MilliTime() {
160 #if defined(__linux__)
161   timespec now;
162   clock_gettime(CLOCK_MONOTONIC, &now);
163   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000) + now.tv_nsec / UINT64_C(1000000);
164 #else
165   timeval now;
166   GetTimeOfDay(&now, nullptr);
167   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000) + now.tv_usec / UINT64_C(1000);
168 #endif
169 }
170 
171 uint64_t MicroTime() {
172 #if defined(__linux__)
173   timespec now;
174   clock_gettime(CLOCK_MONOTONIC, &now);
175   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_nsec / UINT64_C(1000);
176 #else
177   timeval now;
178   GetTimeOfDay(&now, nullptr);
179   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_usec;
180 #endif
181 }
182 
183 uint64_t NanoTime() {
184 #if defined(__linux__)
185   timespec now;
186   clock_gettime(CLOCK_MONOTONIC, &now);
187   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
188 #else
189   timeval now;
190   GetTimeOfDay(&now, nullptr);
191   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_usec * UINT64_C(1000);
192 #endif
193 }
194 
195 uint64_t ThreadCpuNanoTime() {
196 #if defined(__linux__)
197   timespec now;
198   clock_gettime(CLOCK_THREAD_CPUTIME_ID, &now);
199   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
200 #else
201   UNIMPLEMENTED(WARNING);
202   return -1;
203 #endif
204 }
205 
206 uint64_t ProcessCpuNanoTime() {
207 #if defined(__linux__)
208   timespec now;
209   clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &now);
210   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
211 #else
212   // We cannot use clock_gettime() here. Return the process wall clock time
213   // (using art::NanoTime, which relies on gettimeofday()) as approximation of
214   // the process CPU time instead.
215   //
216   // Note: clock_gettime() is available from macOS 10.12 (Darwin 16), but we try
217   // to keep things simple here.
218   return NanoTime();
219 #endif
220 }
221 
222 void NanoSleep(uint64_t ns) {
223   timespec tm;
224   tm.tv_sec = SaturatedTimeT(ns / MsToNs(1000));
225   tm.tv_nsec = ns - static_cast<uint64_t>(tm.tv_sec) * MsToNs(1000);
226   nanosleep(&tm, nullptr);
227 }
228 
229 void InitTimeSpec(bool absolute, int clock, int64_t ms, int32_t ns, timespec* ts) {
230   if (absolute) {
231 #if defined(__linux__)
232     clock_gettime(clock, ts);
233 #else
234     UNUSED(clock);
235     timeval tv;
236     GetTimeOfDay(&tv, nullptr);
237     ts->tv_sec = tv.tv_sec;
238     ts->tv_nsec = tv.tv_usec * 1000;
239 #endif
240   } else {
241     ts->tv_sec = 0;
242     ts->tv_nsec = 0;
243   }
244 
245   int64_t end_sec = ts->tv_sec + ms / 1000;
246   constexpr int32_t int32_max = std::numeric_limits<int32_t>::max();
247   if (UNLIKELY(end_sec >= int32_max)) {
248     // Either ms was intended to denote an infinite timeout, or we have a
249     // problem. The former generally uses the largest possible millisecond
250     // or nanosecond value.  Log only in the latter case.
251     constexpr int64_t int64_max = std::numeric_limits<int64_t>::max();
252     if (ms != int64_max && ms != int64_max / (1000 * 1000)) {
253       LOG(INFO) << "Note: end time exceeds INT32_MAX: " << end_sec;
254     }
255     end_sec = int32_max - 1;  // Allow for increment below.
256   }
257   ts->tv_sec = end_sec;
258   ts->tv_nsec = (ts->tv_nsec + (ms % 1000) * 1000000) + ns;
259 
260   // Catch rollover.
261   if (ts->tv_nsec >= 1000000000L) {
262     ts->tv_sec++;
263     ts->tv_nsec -= 1000000000L;
264   }
265 }
266 
267 }  // namespace art
268