Bug 1313420 - Implement Performance.timeOrigin - part 1

https://hg.mozilla.org/mozilla-central/rev/cf0f72f0b0be

1 files changed, 46 insertions, 0 deletions

diff --git a/dom/performance/PerformanceService.cpp b/dom/performance/PerformanceService.cpp
new file mode 100644
index 000000000..cf119af89
--- /dev/null
+++ b/dom/performance/PerformanceService.cpp
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "PerformanceService.h"
+
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/StaticMutex.h"
+#include "mozilla/StaticPtr.h"
+
+namespace mozilla {
+namespace dom {
+
+static StaticRefPtr<PerformanceService> gPerformanceService;
+static StaticMutex gPerformanceServiceMutex;
+
+/* static */ PerformanceService*
+PerformanceService::GetOrCreate()
+{
+  StaticMutexAutoLock al(gPerformanceServiceMutex);
+
+  if (!gPerformanceService) {
+    gPerformanceService = new PerformanceService();
+    ClearOnShutdown(&gPerformanceService);
+  }
+
+  return gPerformanceService;
+}
+
+DOMHighResTimeStamp
+PerformanceService::TimeOrigin(const TimeStamp& aCreationTimeStamp) const
+{
+  return (aCreationTimeStamp - mCreationTimeStamp).ToMilliseconds() +
+           (mCreationEpochTime / PR_USEC_PER_MSEC);
+}
+
+PerformanceService::PerformanceService()
+{
+  mCreationTimeStamp = TimeStamp::Now();
+  mCreationEpochTime = PR_Now();
+}
+
+} // dom namespace
+} // mozilla namespace