AU: Add unit tests for the Terminator class.

terminator.h

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_TERMINATOR_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_TERMINATOR_H__
 
 #include <signal.h>
 
+#include <gtest/gtest_prod.h>  // for FRIEND_TEST
+
 namespace chromeos_update_engine {
 
 // A class allowing graceful delayed exit.
 class Terminator {
  public:
   // Initializes the terminator and sets up signal handlers.
   static void Init();
 
   // Terminates the current process.
   static void Exit();
 
   // Set to true if the terminator should block termination requests in an
   // attempt to block exiting.
   static void set_exit_blocked(bool block) { exit_blocked_ = block ? 1 : 0; }
+  static bool exit_blocked() { return exit_blocked_ != 0; }
 
   // Returns true if the system is trying to terminate the process, false
   // otherwise. Returns true only if exit was blocked when the termination
   // request arrived.
   static bool exit_requested() { return exit_requested_ != 0; }
 
  private:
+  FRIEND_TEST(TerminatorTest, HandleSignalTest);
+  FRIEND_TEST(TerminatorDeathTest, ScopedTerminatorExitUnblockerExitTest);
+
   // The signal handler.
   static void HandleSignal(int signum);
 
   static volatile sig_atomic_t exit_blocked_;
   static volatile sig_atomic_t exit_requested_;
 };
 
 class ScopedTerminatorExitUnblocker {
  public:
   ~ScopedTerminatorExitUnblocker();
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_TERMINATOR_H__