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      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 "android-base/stringprintf.h"
     24 
     25 #include "base/logging.h"
     26 
     27 #if defined(__APPLE__)
     28 #include <sys/time.h>
     29 #endif
     30 
     31 namespace art {
     32 
     33 using android::base::StringPrintf;
     34 
     35 std::string PrettyDuration(uint64_t nano_duration, size_t max_fraction_digits) {
     36   if (nano_duration == 0) {
     37     return "0";
     38   } else {
     39     return FormatDuration(nano_duration, GetAppropriateTimeUnit(nano_duration),
     40                           max_fraction_digits);
     41   }
     42 }
     43 
     44 TimeUnit GetAppropriateTimeUnit(uint64_t nano_duration) {
     45   const uint64_t one_sec = 1000 * 1000 * 1000;
     46   const uint64_t one_ms  = 1000 * 1000;
     47   const uint64_t one_us  = 1000;
     48   if (nano_duration >= one_sec) {
     49     return kTimeUnitSecond;
     50   } else if (nano_duration >= one_ms) {
     51     return kTimeUnitMillisecond;
     52   } else if (nano_duration >= one_us) {
     53     return kTimeUnitMicrosecond;
     54   } else {
     55     return kTimeUnitNanosecond;
     56   }
     57 }
     58 
     59 uint64_t GetNsToTimeUnitDivisor(TimeUnit time_unit) {
     60   const uint64_t one_sec = 1000 * 1000 * 1000;
     61   const uint64_t one_ms  = 1000 * 1000;
     62   const uint64_t one_us  = 1000;
     63 
     64   switch (time_unit) {
     65     case kTimeUnitSecond:
     66       return one_sec;
     67     case kTimeUnitMillisecond:
     68       return one_ms;
     69     case kTimeUnitMicrosecond:
     70       return one_us;
     71     case kTimeUnitNanosecond:
     72       return 1;
     73   }
     74   return 0;
     75 }
     76 
     77 std::string FormatDuration(uint64_t nano_duration, TimeUnit time_unit,
     78                            size_t max_fraction_digits) {
     79   const char* unit = nullptr;
     80   uint64_t divisor = GetNsToTimeUnitDivisor(time_unit);
     81   switch (time_unit) {
     82     case kTimeUnitSecond:
     83       unit = "s";
     84       break;
     85     case kTimeUnitMillisecond:
     86       unit = "ms";
     87       break;
     88     case kTimeUnitMicrosecond:
     89       unit = "us";
     90       break;
     91     case kTimeUnitNanosecond:
     92       unit = "ns";
     93       break;
     94   }
     95   const uint64_t whole_part = nano_duration / divisor;
     96   uint64_t fractional_part = nano_duration % divisor;
     97   if (fractional_part == 0) {
     98     return StringPrintf("%" PRIu64 "%s", whole_part, unit);
     99   } else {
    100     static constexpr size_t kMaxDigits = 30;
    101     size_t avail_digits = kMaxDigits;
    102     char fraction_buffer[kMaxDigits];
    103     char* ptr = fraction_buffer;
    104     uint64_t multiplier = 10;
    105     // This infinite loops if fractional part is 0.
    106     while (avail_digits > 1 && fractional_part * multiplier < divisor) {
    107       multiplier *= 10;
    108       *ptr++ = '0';
    109       avail_digits--;
    110     }
    111     snprintf(ptr, avail_digits, "%" PRIu64, fractional_part);
    112     fraction_buffer[std::min(kMaxDigits - 1, max_fraction_digits)] = '\0';
    113     return StringPrintf("%" PRIu64 ".%s%s", whole_part, fraction_buffer, unit);
    114   }
    115 }
    116 
    117 std::string GetIsoDate() {
    118   time_t now = time(nullptr);
    119   tm tmbuf;
    120   tm* ptm = localtime_r(&now, &tmbuf);
    121   return StringPrintf("%04d-%02d-%02d %02d:%02d:%02d",
    122       ptm->tm_year + 1900, ptm->tm_mon+1, ptm->tm_mday,
    123       ptm->tm_hour, ptm->tm_min, ptm->tm_sec);
    124 }
    125 
    126 uint64_t MilliTime() {
    127 #if defined(__linux__)
    128   timespec now;
    129   clock_gettime(CLOCK_MONOTONIC, &now);
    130   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000) + now.tv_nsec / UINT64_C(1000000);
    131 #else  // __APPLE__
    132   timeval now;
    133   gettimeofday(&now, nullptr);
    134   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000) + now.tv_usec / UINT64_C(1000);
    135 #endif
    136 }
    137 
    138 uint64_t MicroTime() {
    139 #if defined(__linux__)
    140   timespec now;
    141   clock_gettime(CLOCK_MONOTONIC, &now);
    142   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_nsec / UINT64_C(1000);
    143 #else  // __APPLE__
    144   timeval now;
    145   gettimeofday(&now, nullptr);
    146   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000) + now.tv_usec;
    147 #endif
    148 }
    149 
    150 uint64_t NanoTime() {
    151 #if defined(__linux__)
    152   timespec now;
    153   clock_gettime(CLOCK_MONOTONIC, &now);
    154   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
    155 #else  // __APPLE__
    156   timeval now;
    157   gettimeofday(&now, nullptr);
    158   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_usec * UINT64_C(1000);
    159 #endif
    160 }
    161 
    162 uint64_t ThreadCpuNanoTime() {
    163 #if defined(__linux__)
    164   timespec now;
    165   clock_gettime(CLOCK_THREAD_CPUTIME_ID, &now);
    166   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
    167 #else  // __APPLE__
    168   UNIMPLEMENTED(WARNING);
    169   return -1;
    170 #endif
    171 }
    172 
    173 uint64_t ProcessCpuNanoTime() {
    174 #if defined(__linux__)
    175   timespec now;
    176   clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &now);
    177   return static_cast<uint64_t>(now.tv_sec) * UINT64_C(1000000000) + now.tv_nsec;
    178 #else
    179   UNIMPLEMENTED(WARNING);
    180   return -1;
    181 #endif
    182 }
    183 
    184 void NanoSleep(uint64_t ns) {
    185   timespec tm;
    186   tm.tv_sec = ns / MsToNs(1000);
    187   tm.tv_nsec = ns - static_cast<uint64_t>(tm.tv_sec) * MsToNs(1000);
    188   nanosleep(&tm, nullptr);
    189 }
    190 
    191 void InitTimeSpec(bool absolute, int clock, int64_t ms, int32_t ns, timespec* ts) {
    192   if (absolute) {
    193 #if !defined(__APPLE__)
    194     clock_gettime(clock, ts);
    195 #else
    196     UNUSED(clock);
    197     timeval tv;
    198     gettimeofday(&tv, nullptr);
    199     ts->tv_sec = tv.tv_sec;
    200     ts->tv_nsec = tv.tv_usec * 1000;
    201 #endif
    202   } else {
    203     ts->tv_sec = 0;
    204     ts->tv_nsec = 0;
    205   }
    206 
    207   int64_t end_sec = ts->tv_sec + ms / 1000;
    208   constexpr int32_t int32_max = std::numeric_limits<int32_t>::max();
    209   if (UNLIKELY(end_sec >= int32_max)) {
    210     // Either ms was intended to denote an infinite timeout, or we have a
    211     // problem. The former generally uses the largest possible millisecond
    212     // or nanosecond value.  Log only in the latter case.
    213     constexpr int64_t int64_max = std::numeric_limits<int64_t>::max();
    214     if (ms != int64_max && ms != int64_max / (1000 * 1000)) {
    215       LOG(INFO) << "Note: end time exceeds INT32_MAX: " << end_sec;
    216     }
    217     end_sec = int32_max - 1;  // Allow for increment below.
    218   }
    219   ts->tv_sec = end_sec;
    220   ts->tv_nsec = (ts->tv_nsec + (ms % 1000) * 1000000) + ns;
    221 
    222   // Catch rollover.
    223   if (ts->tv_nsec >= 1000000000L) {
    224     ts->tv_sec++;
    225     ts->tv_nsec -= 1000000000L;
    226   }
    227 }
    228 
    229 }  // namespace art
    230