1 // Copyright (c) 2010 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_THREADING_THREAD_CHECKER_H_ 6 #define BASE_THREADING_THREAD_CHECKER_H_ 7 #pragma once 8 9 #ifndef NDEBUG 10 #include "base/threading/thread_checker_impl.h" 11 #endif 12 13 namespace base { 14 15 // Do nothing implementation, for use in release mode. 16 // 17 // Note: You should almost always use the ThreadChecker class to get the 18 // right version for your build configuration. 19 class ThreadCheckerDoNothing { 20 public: CalledOnValidThread()21 bool CalledOnValidThread() const { 22 return true; 23 } 24 DetachFromThread()25 void DetachFromThread() {} 26 }; 27 28 // Before using this class, please consider using NonThreadSafe as it 29 // makes it much easier to determine the nature of your class. 30 // 31 // ThreadChecker is a helper class used to help verify that some methods of a 32 // class are called from the same thread. One can inherit from this class and 33 // use CalledOnValidThread() to verify. 34 // 35 // Inheriting from class indicates that one must be careful when using the 36 // class with multiple threads. However, it is up to the class document to 37 // indicate how it can be used with threads. 38 // 39 // Example: 40 // class MyClass : public ThreadChecker { 41 // public: 42 // void Foo() { 43 // DCHECK(CalledOnValidThread()); 44 // ... (do stuff) ... 45 // } 46 // } 47 // 48 // In Release mode, CalledOnValidThread will always return true. 49 #ifndef NDEBUG 50 class ThreadChecker : public ThreadCheckerImpl { 51 }; 52 #else 53 class ThreadChecker : public ThreadCheckerDoNothing { 54 }; 55 #endif // NDEBUG 56 57 } // namespace base 58 59 #endif // BASE_THREADING_THREAD_CHECKER_H_ 60