Index: base/task_scheduler/sequence.h |
diff --git a/base/task_scheduler/sequence.h b/base/task_scheduler/sequence.h |
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+// Copyright 2016 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef BASE_TASK_SCHEDULER_SEQUENCE_H_ |
+#define BASE_TASK_SCHEDULER_SEQUENCE_H_ |
+ |
+#include <stddef.h> |
+ |
+#include <queue> |
+ |
+#include "base/base_export.h" |
+#include "base/macros.h" |
+#include "base/memory/ref_counted.h" |
+#include "base/memory/scoped_ptr.h" |
+#include "base/task_scheduler/scheduler_lock.h" |
+#include "base/task_scheduler/sequence_sort_key.h" |
+#include "base/task_scheduler/task.h" |
+#include "base/task_scheduler/task_traits.h" |
+ |
+namespace base { |
+namespace internal { |
+ |
+// A sequence holds tasks that must be executed in posting order. This class is |
robliao
2016/02/19 02:33:43
Nit: Linebreak after the period here is okay.
fdoray
2016/02/19 14:12:14
Done.
|
+// thread-safe. |
+class BASE_EXPORT Sequence : public RefCountedThreadSafe<Sequence> { |
+ public: |
+ Sequence(); |
+ |
+ // Adds |task| at the end of the sequence's queue. Returns true if the |
+ // sequence was empty before this operation. |
+ bool PushTask(scoped_ptr<Task> task); |
+ |
+ // Returns the task in front of the sequence's queue, if any. |
+ const Task* PeekTask() const; |
+ |
+ // Removes the task in front of the sequence's queue. Returns true if the |
+ // sequence is empty after this operation. Cannot be called on an empty |
+ // sequence. |
+ bool PopTask(); |
+ |
+ // Returns a SequenceSortKey to use when inserting the sequence in a priority |
+ // queue. Cannot be called on an empty sequence. |
+ SequenceSortKey GetSortKey() const; |
+ |
+ private: |
+ friend class RefCountedThreadSafe<Sequence>; |
+ ~Sequence(); |
+ |
+ // Controls access to all members. |
robliao
2016/02/19 02:33:43
Nit: Synchronizes access to all members.
fdoray
2016/02/19 14:12:14
Done.
|
+ mutable SchedulerLock lock_; |
+ |
+ // Queue of tasks to execute. |
+ std::queue<scoped_ptr<Task>> queue_; |
+ |
+ // Number of task priorities in the TaskPriority enum. |
+ static const size_t kNumTaskPriorities = |
robliao
2016/02/19 02:33:43
Shouldn't this be taken from task_traits.h?
fdoray
2016/02/19 14:12:14
Done.
|
+ static_cast<TaskPriorityUnderlyingType>(TaskPriority::HIGHEST) + 1; |
robliao
2016/02/19 02:33:43
This seems like something that should remain at or
fdoray
2016/02/19 14:12:14
Done.
|
+ |
+ // Number of tasks contained in the sequence for each priority. |
+ size_t num_tasks_per_priority_[kNumTaskPriorities] = {}; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(Sequence); |
+}; |
+ |
+} // namespace internal |
+} // namespace base |
+ |
+#endif // BASE_TASK_SCHEDULER_SEQUENCE_H_ |