1 // Copyright (c) 2011 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_PENDING_TASK_H_ 6 #define BASE_PENDING_TASK_H_ 7 8 #include <queue> 9 10 #include "base/base_export.h" 11 #include "base/callback.h" 12 #include "base/location.h" 13 #include "base/time/time.h" 14 #include "base/tracking_info.h" 15 16 namespace base { 17 18 // Contains data about a pending task. Stored in TaskQueue and DelayedTaskQueue 19 // for use by classes that queue and execute tasks. 20 struct BASE_EXPORT PendingTask : public TrackingInfo { 21 PendingTask(const tracked_objects::Location& posted_from, 22 const Closure& task); 23 PendingTask(const tracked_objects::Location& posted_from, 24 const Closure& task, 25 TimeTicks delayed_run_time, 26 bool nestable); 27 ~PendingTask(); 28 29 // Used to support sorting. 30 bool operator<(const PendingTask& other) const; 31 32 // The task to run. 33 Closure task; 34 35 // The site this PendingTask was posted from. 36 tracked_objects::Location posted_from; 37 38 // Secondary sort key for run time. 39 int sequence_num; 40 41 // OK to dispatch from a nested loop. 42 bool nestable; 43 44 // Needs high resolution timers. 45 bool is_high_res; 46 }; 47 48 // Wrapper around std::queue specialized for PendingTask which adds a Swap 49 // helper method. 50 class BASE_EXPORT TaskQueue : public std::queue<PendingTask> { 51 public: 52 void Swap(TaskQueue* queue); 53 }; 54 55 // PendingTasks are sorted by their |delayed_run_time| property. 56 typedef std::priority_queue<base::PendingTask> DelayedTaskQueue; 57 58 } // namespace base 59 60 #endif // BASE_PENDING_TASK_H_ 61