dolphin/Source/Core/Common/WorkQueueThread.h
2017-08-20 14:40:56 -07:00

87 lines
1.6 KiB
C++

// Copyright 2017 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#pragma once
#include <functional>
#include <queue>
#include <thread>
#include "Common/Event.h"
#include "Common/Flag.h"
// A thread that executes the given function for every item placed into its queue.
namespace Common
{
template <typename T>
class WorkQueueThread
{
public:
WorkQueueThread() = default;
WorkQueueThread(std::function<void(T)> function) { Reset(std::move(function)); }
~WorkQueueThread() { Shutdown(); }
void Reset(std::function<void(T)> function)
{
Shutdown();
m_shutdown.Clear();
m_function = std::move(function);
m_thread = std::thread([this] { ThreadLoop(); });
}
template <typename... Args>
void EmplaceItem(Args&&... args)
{
{
std::unique_lock<std::mutex> lg(m_lock);
m_items.emplace(std::forward<Args>(args)...);
}
m_wakeup.Set();
}
private:
void Shutdown()
{
if (m_thread.joinable())
{
m_shutdown.Set();
m_wakeup.Set();
m_thread.join();
}
}
void ThreadLoop()
{
while (true)
{
m_wakeup.Wait();
while (true)
{
T item;
{
std::unique_lock<std::mutex> lg(m_lock);
if (m_items.empty())
break;
item = m_items.front();
m_items.pop();
}
m_function(std::move(item));
}
if (m_shutdown.IsSet())
break;
}
}
std::function<void(T)> m_function;
std::thread m_thread;
Common::Event m_wakeup;
Common::Flag m_shutdown;
std::mutex m_lock;
std::queue<T> m_items;
};
} // namespace Common