79 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			79 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C++
		
	
	
	
| /*
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|  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
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|  *
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|  *  Use of this source code is governed by a BSD-style license
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|  *  that can be found in the LICENSE file in the root of the source
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|  *  tree. An additional intellectual property rights grant can be found
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|  *  in the file PATENTS.  All contributing project authors may
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|  *  be found in the AUTHORS file in the root of the source tree.
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|  */
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| 
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| #ifndef RTC_BASE_RACE_CHECKER_H_
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| #define RTC_BASE_RACE_CHECKER_H_
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| 
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| #include "rtc_base/checks.h"
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| #include "rtc_base/platform_thread_types.h"
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| #include "rtc_base/thread_annotations.h"
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| 
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| namespace rtc {
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| 
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| namespace internal {
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| class RaceCheckerScope;
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| }  // namespace internal
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| 
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| // Best-effort race-checking implementation. This primitive uses no
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| // synchronization at all to be as-fast-as-possible in the non-racy case.
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| class RTC_LOCKABLE RaceChecker {
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|  public:
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|   friend class internal::RaceCheckerScope;
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|   RaceChecker();
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| 
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|  private:
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|   bool Acquire() const RTC_EXCLUSIVE_LOCK_FUNCTION();
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|   void Release() const RTC_UNLOCK_FUNCTION();
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| 
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|   // Volatile to prevent code being optimized away in Acquire()/Release().
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|   mutable volatile int access_count_ = 0;
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|   mutable volatile PlatformThreadRef accessing_thread_;
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| };
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| 
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| namespace internal {
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| class RTC_SCOPED_LOCKABLE RaceCheckerScope {
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|  public:
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|   explicit RaceCheckerScope(const RaceChecker* race_checker)
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|       RTC_EXCLUSIVE_LOCK_FUNCTION(race_checker);
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| 
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|   bool RaceDetected() const;
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|   ~RaceCheckerScope() RTC_UNLOCK_FUNCTION();
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| 
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|  private:
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|   const RaceChecker* const race_checker_;
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|   const bool race_check_ok_;
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| };
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| 
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| class RTC_SCOPED_LOCKABLE RaceCheckerScopeDoNothing {
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|  public:
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|   explicit RaceCheckerScopeDoNothing(const RaceChecker* race_checker)
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|       RTC_EXCLUSIVE_LOCK_FUNCTION(race_checker) {}
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| 
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|   ~RaceCheckerScopeDoNothing() RTC_UNLOCK_FUNCTION() {}
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| };
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| 
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| }  // namespace internal
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| }  // namespace rtc
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| 
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| #define RTC_CHECK_RUNS_SERIALIZED(x)               \
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|   rtc::internal::RaceCheckerScope race_checker(x); \
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|   RTC_CHECK(!race_checker.RaceDetected())
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| 
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| #if RTC_DCHECK_IS_ON
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| #define RTC_DCHECK_RUNS_SERIALIZED(x)              \
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|   rtc::internal::RaceCheckerScope race_checker(x); \
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|   RTC_DCHECK(!race_checker.RaceDetected())
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| #else
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| #define RTC_DCHECK_RUNS_SERIALIZED(x) \
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|   rtc::internal::RaceCheckerScopeDoNothing race_checker(x)
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| #endif
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| 
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| #endif  // RTC_BASE_RACE_CHECKER_H_
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