44 lines
1.2 KiB
C++
44 lines
1.2 KiB
C++
// Copyright (c) 2011 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef BASE_SYNCHRONIZATION_CANCELLATION_FLAG_H_
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#define BASE_SYNCHRONIZATION_CANCELLATION_FLAG_H_
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#include "base/base_export.h"
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#include "base/atomicops.h"
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#include "base/threading/platform_thread.h"
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namespace base {
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// CancellationFlag allows one thread to cancel jobs executed on some worker
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// thread. Calling Set() from one thread and IsSet() from a number of threads
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// is thread-safe.
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//
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// This class IS NOT intended for synchronization between threads.
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class BASE_EXPORT CancellationFlag {
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public:
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CancellationFlag() : flag_(false) {
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#if !defined(NDEBUG)
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set_on_ = PlatformThread::CurrentId();
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#endif
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}
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~CancellationFlag() {}
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// Set the flag. May only be called on the thread which owns the object.
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void Set();
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bool IsSet() const; // Returns true iff the flag was set.
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private:
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base::subtle::Atomic32 flag_;
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#if !defined(NDEBUG)
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PlatformThreadId set_on_;
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#endif
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DISALLOW_COPY_AND_ASSIGN(CancellationFlag);
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};
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} // namespace base
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#endif // BASE_SYNCHRONIZATION_CANCELLATION_FLAG_H_
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