53 lines
1.7 KiB
C++
53 lines
1.7 KiB
C++
// Copyright (c) 2012 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_SEQUENCE_CHECKER_IMPL_H_
|
|
#define BASE_SEQUENCE_CHECKER_IMPL_H_
|
|
|
|
#include "base/base_export.h"
|
|
#include "base/basictypes.h"
|
|
#include "base/synchronization/lock.h"
|
|
#include "base/threading/sequenced_worker_pool.h"
|
|
#include "base/threading/thread_checker_impl.h"
|
|
|
|
namespace base {
|
|
|
|
// SequenceCheckerImpl is used to help verify that some methods of a
|
|
// class are called in sequence -- that is, called from the same
|
|
// SequencedTaskRunner. It is a generalization of ThreadChecker; in
|
|
// particular, it behaves exactly like ThreadChecker if constructed
|
|
// on a thread that is not part of a SequencedWorkerPool.
|
|
class BASE_EXPORT SequenceCheckerImpl {
|
|
public:
|
|
SequenceCheckerImpl();
|
|
~SequenceCheckerImpl();
|
|
|
|
// Returns whether the we are being called on the same sequence token
|
|
// as previous calls. If there is no associated sequence, then returns
|
|
// whether we are being called on the underlying ThreadChecker's thread.
|
|
bool CalledOnValidSequencedThread() const;
|
|
|
|
// Unbinds the checker from the currently associated sequence. The
|
|
// checker will be re-bound on the next call to CalledOnValidSequence().
|
|
void DetachFromSequence();
|
|
|
|
private:
|
|
void EnsureSequenceTokenAssigned() const;
|
|
|
|
// Guards all variables below.
|
|
mutable Lock lock_;
|
|
|
|
// Used if |sequence_token_| is not valid.
|
|
ThreadCheckerImpl thread_checker_;
|
|
mutable bool sequence_token_assigned_;
|
|
|
|
mutable SequencedWorkerPool::SequenceToken sequence_token_;
|
|
|
|
DISALLOW_COPY_AND_ASSIGN(SequenceCheckerImpl);
|
|
};
|
|
|
|
} // namespace base
|
|
|
|
#endif // BASE_SEQUENCE_CHECKER_IMPL_H_
|