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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// 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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#pragma once
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#ifdef _WIN32
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#include <concrt.h>
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#endif
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#include <chrono>
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#include <condition_variable>
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#include <mutex>
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#include "Common/Flag.h"
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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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  void Wait()
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  {
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    if (m_flag.TestAndClear())
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      return;
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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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  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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    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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    return signaled;
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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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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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}  // namespace Common
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