forked from dolphin-emu/dolphin
		
	
		
			
				
	
	
		
			75 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| // Copyright 2014 Dolphin Emulator Project
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| // Licensed under GPLv2+
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| // Refer to the license.txt file included.
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| 
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| // Multithreaded event class. This allows waiting in a thread for an event to
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| // be triggered in another thread. While waiting, the CPU will be available for
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| // other tasks.
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| // * Set(): triggers the event and wakes up the waiting thread.
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| // * Wait(): waits for the event to be triggered.
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| // * Reset(): tries to reset the event before the waiting thread sees it was
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| //            triggered. Usually a bad idea.
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| 
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| #pragma once
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| 
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| #ifdef _WIN32
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| #include <concrt.h>
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| #endif
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| 
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| #include <chrono>
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| #include <condition_variable>
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| #include <mutex>
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| 
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| #include "Common/Flag.h"
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| 
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| namespace Common
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| {
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| class Event final
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| {
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| public:
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|   void Set()
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|   {
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|     if (m_flag.TestAndSet())
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|     {
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|       std::lock_guard<std::mutex> lk(m_mutex);
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|       m_condvar.notify_one();
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|     }
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|   }
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| 
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|   void Wait()
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|   {
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|     if (m_flag.TestAndClear())
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|       return;
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| 
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|     std::unique_lock<std::mutex> lk(m_mutex);
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|     m_condvar.wait(lk, [&] { return m_flag.TestAndClear(); });
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|   }
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| 
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|   template <class Rep, class Period>
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|   bool WaitFor(const std::chrono::duration<Rep, Period>& rel_time)
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|   {
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|     if (m_flag.TestAndClear())
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|       return true;
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| 
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|     std::unique_lock<std::mutex> lk(m_mutex);
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|     bool signaled = m_condvar.wait_for(lk, rel_time, [&] { return m_flag.TestAndClear(); });
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| 
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|     return signaled;
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|   }
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| 
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|   void Reset()
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|   {
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|     // no other action required, since wait loops on
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|     // the predicate and any lingering signal will get
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|     // cleared on the first iteration
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|     m_flag.Clear();
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|   }
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| 
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| private:
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|   Flag m_flag;
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|   std::condition_variable m_condvar;
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|   std::mutex m_mutex;
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| };
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| 
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| }  // namespace Common
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