android/libwvdrmengine/cdm/util/test/test_clock.cpp

// Copyright 2019 Google LLC. All Rights Reserved. This file and proprietary
// source code may only be used and distributed under the Widevine License
// Agreement.
//
// Clock - A fake clock just for running tests. This is used when running
// OEMCrypto unit tests. It is not used when tests include the CE CDM source
// code because that uses the clock in cdm/test_host.cpp instead.

#include <chrono>

#include "clock.h"
#include "test_sleep.h"

namespace wvutil {

namespace {
// A fake clock that only advances when TestSleep::Sleep is called.
class FakeClock : public TestSleep::CallBack {
 public:
  FakeClock() {
    auto now = std::chrono::system_clock().now();
    now_ = now.time_since_epoch() / std::chrono::milliseconds(1);
    TestSleep::set_callback(this);
  }
  ~FakeClock() { TestSleep::set_callback(nullptr); }
  void ElapseTime(int64_t milliseconds) { now_ += milliseconds; }

  int64_t now() const { return now_; }

 private:
  int64_t now_;
};

FakeClock* g_fake_clock = nullptr;
}  // namespace

// On devices running a fake OEMCrypto, we can use a fake sleep and fake time.
int64_t Clock::GetCurrentTime() {
  TestSleep::SyncFakeClock();
  if (g_fake_clock == nullptr) g_fake_clock = new FakeClock();
  return g_fake_clock->now() / 1000;
}

}  // namespace wvutil