| Index: base/task/cancelable_task_tracker.h
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| diff --git a/base/task/cancelable_task_tracker.h b/base/task/cancelable_task_tracker.h
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| deleted file mode 100644
|
| index b8a8b70e333922b41d5e7019070f09e18a6a12e4..0000000000000000000000000000000000000000
|
| --- a/base/task/cancelable_task_tracker.h
|
| +++ /dev/null
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| @@ -1,140 +0,0 @@
|
| -// Copyright 2014 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.
|
| -
|
| -// CancelableTaskTracker posts tasks (in the form of a Closure) to a
|
| -// TaskRunner, and is able to cancel the task later if it's not needed
|
| -// anymore. On destruction, CancelableTaskTracker will cancel all
|
| -// tracked tasks.
|
| -//
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| -// Each cancelable task can be associated with a reply (also a Closure). After
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| -// the task is run on the TaskRunner, |reply| will be posted back to
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| -// originating TaskRunner.
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| -//
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| -// NOTE:
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| -//
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| -// CancelableCallback (base/cancelable_callback.h) and WeakPtr binding are
|
| -// preferred solutions for canceling a task. However, they don't support
|
| -// cancelation from another thread. This is sometimes a performance critical
|
| -// requirement. E.g. We need to cancel database lookup task on DB thread when
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| -// user changes inputed text. If it is performance critical to do a best effort
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| -// cancelation of a task, then CancelableTaskTracker is appropriate,
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| -// otherwise use one of the other mechanisms.
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| -//
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| -// THREAD-SAFETY:
|
| -//
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| -// 1. CancelableTaskTracker objects are not thread safe. They must
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| -// be created, used, and destroyed on the originating thread that posts the
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| -// task. It's safe to destroy a CancelableTaskTracker while there
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| -// are outstanding tasks. This is commonly used to cancel all outstanding
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| -// tasks.
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| -//
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| -// 2. Both task and reply are deleted on the originating thread.
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| -//
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| -// 3. IsCanceledCallback is thread safe and can be run or deleted on any
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| -// thread.
|
| -#ifndef BASE_TASK_CANCELABLE_TASK_TRACKER_H_
|
| -#define BASE_TASK_CANCELABLE_TASK_TRACKER_H_
|
| -
|
| -#include "base/base_export.h"
|
| -#include "base/basictypes.h"
|
| -#include "base/callback.h"
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| -#include "base/containers/hash_tables.h"
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| -#include "base/memory/weak_ptr.h"
|
| -#include "base/task_runner_util.h"
|
| -#include "base/threading/thread_checker.h"
|
| -
|
| -namespace tracked_objects {
|
| -class Location;
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| -} // namespace tracked_objects
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| -
|
| -namespace base {
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| -
|
| -class CancellationFlag;
|
| -class TaskRunner;
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| -
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| -class BASE_EXPORT CancelableTaskTracker {
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| - public:
|
| - // All values except kBadTaskId are valid.
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| - typedef int64 TaskId;
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| - static const TaskId kBadTaskId;
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| -
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| - typedef base::Callback<bool()> IsCanceledCallback;
|
| -
|
| - CancelableTaskTracker();
|
| -
|
| - // Cancels all tracked tasks.
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| - ~CancelableTaskTracker();
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| -
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| - TaskId PostTask(base::TaskRunner* task_runner,
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| - const tracked_objects::Location& from_here,
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| - const base::Closure& task);
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| -
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| - TaskId PostTaskAndReply(base::TaskRunner* task_runner,
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| - const tracked_objects::Location& from_here,
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| - const base::Closure& task,
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| - const base::Closure& reply);
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| -
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| - template <typename TaskReturnType, typename ReplyArgType>
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| - TaskId PostTaskAndReplyWithResult(
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| - base::TaskRunner* task_runner,
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| - const tracked_objects::Location& from_here,
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| - const base::Callback<TaskReturnType(void)>& task,
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| - const base::Callback<void(ReplyArgType)>& reply) {
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| - TaskReturnType* result = new TaskReturnType();
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| - return PostTaskAndReply(
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| - task_runner,
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| - from_here,
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| - base::Bind(&base::internal::ReturnAsParamAdapter<TaskReturnType>,
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| - task,
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| - base::Unretained(result)),
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| - base::Bind(&base::internal::ReplyAdapter<TaskReturnType, ReplyArgType>,
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| - reply,
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| - base::Owned(result)));
|
| - }
|
| -
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| - // Creates a tracked TaskId and an associated IsCanceledCallback. Client can
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| - // later call TryCancel() with the returned TaskId, and run |is_canceled_cb|
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| - // from any thread to check whether the TaskId is canceled.
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| - //
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| - // The returned task ID is tracked until the last copy of
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| - // |is_canceled_cb| is destroyed.
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| - //
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| - // Note. This function is used to address some special cancelation requirement
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| - // in existing code. You SHOULD NOT need this function in new code.
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| - TaskId NewTrackedTaskId(IsCanceledCallback* is_canceled_cb);
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| -
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| - // After calling this function, |task| and |reply| will not run. If the
|
| - // cancelation happens when |task| is running or has finished running, |reply|
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| - // will not run. If |reply| is running or has finished running, cancellation
|
| - // is a noop.
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| - //
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| - // Note. It's OK to cancel a |task| for more than once. The later calls are
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| - // noops.
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| - void TryCancel(TaskId id);
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| -
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| - // It's OK to call this function for more than once. The later calls are
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| - // noops.
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| - void TryCancelAll();
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| -
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| - // Returns true iff there are in-flight tasks that are still being
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| - // tracked.
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| - bool HasTrackedTasks() const;
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| -
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| - private:
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| - void Track(TaskId id, base::CancellationFlag* flag);
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| - void Untrack(TaskId id);
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| -
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| - base::hash_map<TaskId, base::CancellationFlag*> task_flags_;
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| -
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| - TaskId next_id_;
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| - base::ThreadChecker thread_checker_;
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| -
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| - base::WeakPtrFactory<CancelableTaskTracker> weak_factory_;
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| -
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| - DISALLOW_COPY_AND_ASSIGN(CancelableTaskTracker);
|
| -};
|
| -
|
| -} // namespace base
|
| -
|
| -#endif // BASE_TASK_CANCELABLE_TASK_TRACKER_H_
|
|
|