1 files changed, 43 insertions, 0 deletions
diff --git a/dom/performance/PerformanceService.h b/dom/performance/PerformanceService.h
new file mode 100644
index 0000000000..80ded9b180
--- /dev/null
+++ b/dom/performance/PerformanceService.h
@@ -0,0 +1,43 @@
+/* -*- 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/. */
+
+#ifndef dom_performance_PerformanceService_h
+#define dom_performance_PerformanceService_h
+
+#include "mozilla/TimeStamp.h"
+#include "nsCOMPtr.h"
+#include "nsDOMNavigationTiming.h"
+
+namespace mozilla::dom {
+
+// This class is thread-safe.
+
+// We use this singleton for having the correct value of performance.timeOrigin.
+// This value must be calculated on top of the pair:
+// - mCreationTimeStamp (monotonic clock)
+// - mCreationEpochTime (unix epoch time)
+// These 2 values must be taken "at the same time" in order to be used
+// correctly.
+
+class PerformanceService {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(PerformanceService)
+
+  static PerformanceService* GetOrCreate();
+
+  DOMHighResTimeStamp TimeOrigin(const TimeStamp& aCreationTimeStamp) const;
+
+ private:
+  PerformanceService();
+  ~PerformanceService() = default;
+
+  TimeStamp mCreationTimeStamp;
+  PRTime mCreationEpochTime;
+};
+
+}  // namespace mozilla::dom
+
+#endif  // dom_performance_PerformanceService_h