nearby sdk refactor

PiperOrigin-RevId: 425434260

internal/platform/implementation/windows/system_clock.cc

@@ -0,0 +1,43 @@
+// Copyright 2021 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_IMPL_WINDOWS_SYSTEM_CLOCK_H_
+#define PLATFORM_IMPL_WINDOWS_SYSTEM_CLOCK_H_
+
+#include "internal/platform/implementation/system_clock.h"
+
+namespace location {
+namespace nearby {
+
+// Initialize global system state.
+void SystemClock::Init() { }
+
+// Returns current absolute time. It is guaranteed to be monotonic.
+absl::Time SystemClock::ElapsedRealtime() {
+  return absl::FromUnixNanos(
+     std::chrono::duration_cast<std::chrono::nanoseconds>(
+         std::chrono::steady_clock::now().time_since_epoch())
+         .count());
+}
+
+// Pauses current thread for the specified duration.
+Exception SystemClock::Sleep(absl::Duration duration) {
+  absl::SleepFor(duration);
+  return {Exception::kSuccess};
+}
+
+}  // namespace nearby
+}  // namespace location
+
+#endif  // PLATFORM_IMPL_WINDOWS_SYSTEM_CLOCK_H_