1 // Copyright (c) 2012 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_THREAD_TASK_RUNNER_HANDLE_H_ 6 #define BASE_THREAD_TASK_RUNNER_HANDLE_H_ 7 8 #include "base/base_export.h" 9 #include "base/memory/ref_counted.h" 10 11 namespace base { 12 13 class SingleThreadTaskRunner; 14 15 // ThreadTaskRunnerHandle stores a reference to a thread's TaskRunner 16 // in thread-local storage. Callers can then retrieve the TaskRunner 17 // for the current thread by calling ThreadTaskRunnerHandle::Get(). 18 // At most one TaskRunner may be bound to each thread at a time. 19 class BASE_EXPORT ThreadTaskRunnerHandle { 20 public: 21 // Gets the SingleThreadTaskRunner for the current thread. 22 static scoped_refptr<SingleThreadTaskRunner> Get(); 23 24 // Returns true if the SingleThreadTaskRunner is already created for 25 // the current thread. 26 static bool IsSet(); 27 28 // Binds |task_runner| to the current thread. |task_runner| must belong 29 // to the current thread for this to succeed. 30 explicit ThreadTaskRunnerHandle( 31 const scoped_refptr<SingleThreadTaskRunner>& task_runner); 32 ~ThreadTaskRunnerHandle(); 33 34 private: 35 scoped_refptr<SingleThreadTaskRunner> task_runner_; 36 }; 37 38 } // namespace base 39 40 #endif // BASE_THREAD_TASK_RUNNER_HANDLE_H_ 41