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 <inttypes.h>
18 #include <limits>
19 #include <sstream>
20 
21 #include "time_utils.h"
22 
23 #include "base/logging.h"
24 #include "base/stringprintf.h"
25 
26 #if defined(__APPLE__)
27 #include <sys/time.h>
28 #endif
29 
30 namespace art {
31 
PrettyDuration(uint64_t nano_duration,size_t max_fraction_digits)32 std::string PrettyDuration(uint64_t nano_duration, size_t max_fraction_digits) {
33   if (nano_duration == 0) {
34     return "0";
35   } else {
36     return FormatDuration(nano_duration, GetAppropriateTimeUnit(nano_duration),
37                           max_fraction_digits);
38   }
39 }
40 
GetAppropriateTimeUnit(uint64_t nano_duration)41 TimeUnit GetAppropriateTimeUnit(uint64_t nano_duration) {
42   const uint64_t one_sec = 1000 * 1000 * 1000;
43   const uint64_t one_ms  = 1000 * 1000;
44   const uint64_t one_us  = 1000;
45   if (nano_duration >= one_sec) {
46     return kTimeUnitSecond;
47   } else if (nano_duration >= one_ms) {
48     return kTimeUnitMillisecond;
49   } else if (nano_duration >= one_us) {
50     return kTimeUnitMicrosecond;
51   } else {
52     return kTimeUnitNanosecond;
53   }
54 }
55 
GetNsToTimeUnitDivisor(TimeUnit time_unit)56 uint64_t GetNsToTimeUnitDivisor(TimeUnit time_unit) {
57   const uint64_t one_sec = 1000 * 1000 * 1000;
58   const uint64_t one_ms  = 1000 * 1000;
59   const uint64_t one_us  = 1000;
60 
61   switch (time_unit) {
62     case kTimeUnitSecond:
63       return one_sec;
64     case kTimeUnitMillisecond:
65       return one_ms;
66     case kTimeUnitMicrosecond:
67       return one_us;
68     case kTimeUnitNanosecond:
69       return 1;
70   }
71   return 0;
72 }
73 
FormatDuration(uint64_t nano_duration,TimeUnit time_unit,size_t max_fraction_digits)74 std::string FormatDuration(uint64_t nano_duration, TimeUnit time_unit,
75                            size_t max_fraction_digits) {
76   const char* unit = nullptr;
77   uint64_t divisor = GetNsToTimeUnitDivisor(time_unit);
78   switch (time_unit) {
79     case kTimeUnitSecond:
80       unit = "s";
81       break;
82     case kTimeUnitMillisecond:
83       unit = "ms";
84       break;
85     case kTimeUnitMicrosecond:
86       unit = "us";
87       break;
88     case kTimeUnitNanosecond:
89       unit = "ns";
90       break;
91   }
92   const uint64_t whole_part = nano_duration / divisor;
93   uint64_t fractional_part = nano_duration % divisor;
94   if (fractional_part == 0) {
95     return StringPrintf("%" PRIu64 "%s", whole_part, unit);
96   } else {
97     static constexpr size_t kMaxDigits = 30;
98     size_t avail_digits = kMaxDigits;
99     char fraction_buffer[kMaxDigits];
100     char* ptr = fraction_buffer;
101     uint64_t multiplier = 10;
102     // This infinite loops if fractional part is 0.
103     while (avail_digits > 1 && fractional_part * multiplier < divisor) {
104       multiplier *= 10;
105       *ptr++ = '0';
106       avail_digits--;
107     }
108     snprintf(ptr, avail_digits, "%" PRIu64, fractional_part);
109     fraction_buffer[std::min(kMaxDigits - 1, max_fraction_digits)] = '\0';
110     return StringPrintf("%" PRIu64 ".%s%s", whole_part, fraction_buffer, unit);
111   }
112 }
113 
GetIsoDate()114 std::string GetIsoDate() {
115   time_t now = time(nullptr);
116   tm tmbuf;
117   tm* ptm = localtime_r(&now, &tmbuf);
118   return StringPrintf("%04d-%02d-%02d %02d:%02d:%02d",
119       ptm->tm_year + 1900, ptm->tm_mon+1, ptm->tm_mday,
120       ptm->tm_hour, ptm->tm_min, ptm->tm_sec);
121 }
122 
MilliTime()123 uint64_t MilliTime() {
124 #if defined(__linux__)
125   timespec now;
126   clock_gettime(CLOCK_MONOTONIC, &now);
127   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000) + now.tv_nsec / UINT64_C(1000000);
128 #else  // __APPLE__
129   timeval now;
130   gettimeofday(&now, nullptr);
131   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000) + now.tv_usec / UINT64_C(1000);
132 #endif
133 }
134 
MicroTime()135 uint64_t MicroTime() {
136 #if defined(__linux__)
137   timespec now;
138   clock_gettime(CLOCK_MONOTONIC, &now);
139   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_nsec / UINT64_C(1000);
140 #else  // __APPLE__
141   timeval now;
142   gettimeofday(&now, nullptr);
143   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_usec;
144 #endif
145 }
146 
NanoTime()147 uint64_t NanoTime() {
148 #if defined(__linux__)
149   timespec now;
150   clock_gettime(CLOCK_MONOTONIC, &now);
151   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
152 #else  // __APPLE__
153   timeval now;
154   gettimeofday(&now, nullptr);
155   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_usec * UINT64_C(1000);
156 #endif
157 }
158 
ThreadCpuNanoTime()159 uint64_t ThreadCpuNanoTime() {
160 #if defined(__linux__)
161   timespec now;
162   clock_gettime(CLOCK_THREAD_CPUTIME_ID, &now);
163   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
164 #else  // __APPLE__
165   UNIMPLEMENTED(WARNING);
166   return -1;
167 #endif
168 }
169 
NanoSleep(uint64_t ns)170 void NanoSleep(uint64_t ns) {
171   timespec tm;
172   tm.tv_sec = ns / MsToNs(1000);
173   tm.tv_nsec = ns - static_cast<uint64_t>(tm.tv_sec) * MsToNs(1000);
174   nanosleep(&tm, nullptr);
175 }
176 
InitTimeSpec(bool absolute,int clock,int64_t ms,int32_t ns,timespec * ts)177 void InitTimeSpec(bool absolute, int clock, int64_t ms, int32_t ns, timespec* ts) {
178   if (absolute) {
179 #if !defined(__APPLE__)
180     clock_gettime(clock, ts);
181 #else
182     UNUSED(clock);
183     timeval tv;
184     gettimeofday(&tv, nullptr);
185     ts->tv_sec = tv.tv_sec;
186     ts->tv_nsec = tv.tv_usec * 1000;
187 #endif
188   } else {
189     ts->tv_sec = 0;
190     ts->tv_nsec = 0;
191   }
192 
193   int64_t end_sec = ts->tv_sec + ms / 1000;
194   constexpr int32_t int32_max = std::numeric_limits<int32_t>::max();
195   if (UNLIKELY(end_sec >= int32_max)) {
196     // Either ms was intended to denote an infinite timeout, or we have a
197     // problem. The former generally uses the largest possible millisecond
198     // or nanosecond value.  Log only in the latter case.
199     constexpr int64_t int64_max = std::numeric_limits<int64_t>::max();
200     if (ms != int64_max && ms != int64_max / (1000 * 1000)) {
201       LOG(INFO) << "Note: end time exceeds INT32_MAX: " << end_sec;
202     }
203     end_sec = int32_max - 1;  // Allow for increment below.
204   }
205   ts->tv_sec = end_sec;
206   ts->tv_nsec = (ts->tv_nsec + (ms % 1000) * 1000000) + ns;
207 
208   // Catch rollover.
209   if (ts->tv_nsec >= 1000000000L) {
210     ts->tv_sec++;
211     ts->tv_nsec -= 1000000000L;
212   }
213 }
214 
215 }  // namespace art
216