Source release 16.3.0

util/test/test_sleep.h

@@ -22,8 +22,9 @@ class TestSleep {
     virtual ~CallBack(){};
   };
 
-  // If real_sleep_ is true, then this sleeps for |seconds| of time.
-  // If the callback exists, this calls the callback.
+  // If real_sleep_ is true, then this sleeps for |seconds| of time.  If
+  // real_sleep_ is false, then the fake clock is advanced by |seconds|. If the
+  // callback exists, this calls the callback.
   static void Sleep(unsigned int seconds);
 
   // If we are using a real clock and a fake clock, then the real clock advances
@@ -33,8 +34,30 @@ class TestSleep {
   // failing due to this drift.
   static void SyncFakeClock();
 
-  static void set_real_sleep(bool real_sleep) { real_sleep_ = real_sleep; }
+  // Roll the system clock back by |seconds|. Returns true on success. A well
+  // mannered test will call CanChangeSystemTime before attempting to call this
+  // function and then assert that this is true. This function should *NOT* roll
+  // back the clock used by OEMCrypto -- in fact, there are several tests that
+  // verify this function does not roll back the clock used by OEMCrypto.
+  static bool RollbackSystemTime(int seconds);
 
+  // Roll the system clock forward to undo all previous calls to
+  // RollBackSystemTime. Returns true on success.
+  static bool ResetRollback() {
+    return total_clock_rollback_ == 0 ||
+           RollbackSystemTime(-total_clock_rollback_);
+  }
+
+  // Returns true if the system time can be rolled back. This is true on some
+  // devices if the tests are run as root. It is also true when using a fake
+  // clock with the reference version of OEMCrypto. This function is about the
+  // system clock, *NOT* the clock used by OEMCrypto.
+  static bool CanChangeSystemTime();
+
+  static void set_real_sleep(bool real_sleep) { real_sleep_ = real_sleep; }
+  static bool real_sleep() { return real_sleep_; }
+
+  // The callback is notified whenever sleep is called.
   static void set_callback(CallBack* callback) { callback_ = callback; }
 
  private:
@@ -42,6 +65,9 @@ class TestSleep {
   static bool real_sleep_;
   // Called when the clock should advance.
   static CallBack* callback_;
+  // The sum of all calls to RollBackSystemTime. Kept so we can undo all changes
+  // at the end of a test.
+  static int total_clock_rollback_;
 };
 
 }  // namespace wvcdm