dom/performance/PerformanceService.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "PerformanceService.h"
   8
   9 #include "mozilla/ClearOnShutdown.h"
  10 #include "mozilla/StaticMutex.h"
  11 #include "mozilla/StaticPtr.h"
  12 #include "prtime.h"
  13
  14 namespace mozilla::dom {
  15
  16 static StaticRefPtr<PerformanceService> gPerformanceService;
  17 static StaticMutex gPerformanceServiceMutex MOZ_UNANNOTATED;
  18
  19 /* static */
  20 PerformanceService* PerformanceService::GetOrCreate() {
  21   StaticMutexAutoLock al(gPerformanceServiceMutex);
  22
  23   if (!gPerformanceService) {
  24     gPerformanceService = new PerformanceService();
  25     ClearOnShutdown(&gPerformanceService);
  26   }
  27
  28   return gPerformanceService;
  29 }
  30
  31 DOMHighResTimeStamp PerformanceService::TimeOrigin(
  32     const TimeStamp& aCreationTimeStamp) const {
  33   return (aCreationTimeStamp - mCreationTimeStamp).ToMilliseconds() +
  34          (mCreationEpochTime / PR_USEC_PER_MSEC);
  35 }
  36
  37 PerformanceService::PerformanceService() {
  38   mCreationTimeStamp = TimeStamp::Now();
  39   mCreationEpochTime = PR_Now();
  40 }
  41
  42 }  // namespace mozilla::dom