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* Copyright 2012 Google Inc.
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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// Author: jmarantz@google.com (Joshua Marantz)
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#ifndef PAGESPEED_KERNEL_BASE_NULL_RW_LOCK_H_
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#define PAGESPEED_KERNEL_BASE_NULL_RW_LOCK_H_
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#include "pagespeed/kernel/base/thread_annotations.h"
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#include "pagespeed/kernel/base/thread_system.h"
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namespace net_instaweb {
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// Implements an empty mutex for single-threaded programs that need to work
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// with interfaces that require mutexes.
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class LOCKABLE NullRWLock : public ThreadSystem::RWLock {
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virtual ~NullRWLock();
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virtual bool TryLock() EXCLUSIVE_TRYLOCK_FUNCTION(true);
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virtual void Lock() EXCLUSIVE_LOCK_FUNCTION();
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virtual void Unlock() UNLOCK_FUNCTION();
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virtual bool ReaderTryLock() SHARED_TRYLOCK_FUNCTION(true);
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virtual void ReaderLock() SHARED_LOCK_FUNCTION();
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virtual void ReaderUnlock() UNLOCK_FUNCTION();
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virtual void DCheckReaderLocked();
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} // namespace net_instaweb
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#endif // PAGESPEED_KERNEL_BASE_NULL_RW_LOCK_H_