roll forward to cl/317978613

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I988b9fa534d61583b2af67dfef002fa2a5823fb7

cpp/platform_v2/impl/g3/atomic_reference.h

@@ -0,0 +1,47 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef PLATFORM_V2_IMPL_G3_ATOMIC_REFERENCE_H_
+#define PLATFORM_V2_IMPL_G3_ATOMIC_REFERENCE_H_
+
+#include <atomic>
+#include <cstdint>
+
+#include "platform_v2/api/atomic_reference.h"
+
+namespace location {
+namespace nearby {
+namespace g3 {
+
+class AtomicUint32 : public api::AtomicUint32 {
+ public:
+  explicit AtomicUint32(std::int32_t value) : value_(value) {}
+  ~AtomicUint32() override = default;
+
+  std::uint32_t Get() const override {
+    return value_;
+  }
+  void Set(std::uint32_t value) override {
+    value_ = value;
+  }
+
+ private:
+  std::atomic<std::uint32_t> value_;
+};
+
+}  // namespace g3
+}  // namespace nearby
+}  // namespace location
+
+#endif  // PLATFORM_V2_IMPL_G3_ATOMIC_REFERENCE_H_