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               Closure task);
23   PendingTask(const tracked_objects::Location& posted_from,
24               Closure task,
25               TimeTicks delayed_run_time,
26               bool nestable);
27   PendingTask(PendingTask&& other);
28   ~PendingTask();
29 
30   PendingTask& operator=(PendingTask&& other);
31 
32   // Used to support sorting.
33   bool operator<(const PendingTask& other) const;
34 
35   // The task to run.
36   Closure task;
37 
38   // The site this PendingTask was posted from.
39   tracked_objects::Location posted_from;
40 
41   // Secondary sort key for run time.
42   int sequence_num;
43 
44   // OK to dispatch from a nested loop.
45   bool nestable;
46 
47   // Needs high resolution timers.
48   bool is_high_res;
49 };
50 
51 using TaskQueue = std::queue<PendingTask>;
52 
53 // PendingTasks are sorted by their |delayed_run_time| property.
54 using DelayedTaskQueue = std::priority_queue<base::PendingTask>;
55 
56 }  // namespace base
57 
58 #endif  // BASE_PENDING_TASK_H_
59