1 files changed, 40 insertions, 0 deletions
diff --git a/ipc/mscom/SpinEvent.h b/ipc/mscom/SpinEvent.h
new file mode 100644
index 0000000000..461865a6bc
--- /dev/null
+++ b/ipc/mscom/SpinEvent.h
@@ -0,0 +1,40 @@
+/* -*- 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 mozilla_mscom_SpinEvent_h
+#define mozilla_mscom_SpinEvent_h
+
+#include "mozilla/Atomics.h"
+#include "mozilla/Attributes.h"
+#include "nsWindowsHelpers.h"
+
+namespace mozilla {
+namespace mscom {
+
+class MOZ_NON_TEMPORARY_CLASS SpinEvent final {
+ public:
+  SpinEvent();
+  ~SpinEvent() = default;
+
+  bool Wait(HANDLE aTargetThread);
+  void Signal();
+
+  SpinEvent(const SpinEvent&) = delete;
+  SpinEvent(SpinEvent&&) = delete;
+  SpinEvent& operator=(SpinEvent&&) = delete;
+  SpinEvent& operator=(const SpinEvent&) = delete;
+
+ private:
+  Atomic<bool, ReleaseAcquire> mDone;
+  nsAutoHandle mDoneEvent;
+  static bool InitStatics();
+  static bool sIsMulticore;
+};
+
+}  // namespace mscom
+}  // namespace mozilla
+
+#endif  // mozilla_mscom_SpinEvent_h