utils/benchmark/src/sleep.cc

   1 // Copyright 2015 Google Inc. All rights reserved.
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 #include "sleep.h"
  16
  17 #include <cerrno>
  18 #include <cstdlib>
  19 #include <ctime>
  20
  21 #include "internal_macros.h"
  22
  23 #ifdef BENCHMARK_OS_WINDOWS
  24 #include <windows.h>
  25 #endif
  26
  27 namespace benchmark {
  28 #ifdef BENCHMARK_OS_WINDOWS
  29 // Window's Sleep takes milliseconds argument.
  30 void SleepForMilliseconds(int milliseconds) { Sleep(milliseconds); }
  31 void SleepForSeconds(double seconds) {
  32   SleepForMilliseconds(static_cast<int>(kNumMillisPerSecond * seconds));
  33 }
  34 #else   // BENCHMARK_OS_WINDOWS
  35 void SleepForMicroseconds(int microseconds) {
  36   struct timespec sleep_time;
  37   sleep_time.tv_sec = microseconds / kNumMicrosPerSecond;
  38   sleep_time.tv_nsec = (microseconds % kNumMicrosPerSecond) * kNumNanosPerMicro;
  39   while (nanosleep(&sleep_time, &sleep_time) != 0 && errno == EINTR)
  40     ;  // Ignore signals and wait for the full interval to elapse.
  41 }
  42
  43 void SleepForMilliseconds(int milliseconds) {
  44   SleepForMicroseconds(milliseconds * kNumMicrosPerMilli);
  45 }
  46
  47 void SleepForSeconds(double seconds) {
  48   SleepForMicroseconds(static_cast<int>(seconds * kNumMicrosPerSecond));
  49 }
  50 #endif  // BENCHMARK_OS_WINDOWS
  51 }  // end namespace benchmark