1 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_NON_THREAD_SAFE_H__ 6 #define BASE_NON_THREAD_SAFE_H__ 7 8 #include "base/platform_thread.h" 9 10 // A helper class used to help verify that methods of a class are 11 // called from the same thread. One can inherit from this class and use 12 // CalledOnValidThread() to verify. 13 // 14 // This is intended to be used with classes that appear to be thread safe, but 15 // aren't. For example, a service or a singleton like the preferences system. 16 // 17 // Example: 18 // class MyClass : public NonThreadSafe { 19 // public: 20 // void Foo() { 21 // DCHECK(CalledOnValidThread()); 22 // ... (do stuff) ... 23 // } 24 // } 25 // 26 // In Release mode, CalledOnValidThread will always return true. 27 // 28 #ifndef NDEBUG 29 class NonThreadSafe { 30 public: 31 NonThreadSafe(); 32 ~NonThreadSafe(); 33 34 bool CalledOnValidThread() const; 35 36 private: 37 PlatformThreadId valid_thread_id_; 38 }; 39 #else 40 // Do nothing in release mode. 41 class NonThreadSafe { 42 public: NonThreadSafe()43 NonThreadSafe() {} ~NonThreadSafe()44 ~NonThreadSafe() {} 45 CalledOnValidThread()46 bool CalledOnValidThread() const { 47 return true; 48 } 49 }; 50 #endif // NDEBUG 51 52 #endif // BASE_NON_THREAD_SAFE_H__ 53