win32/ComWorker: use std::queue/Mutex/Cond instead of boost::lockfree::spsc_queue/WinEvent

src/win32/ComWorker.cxx

@@ -28,15 +28,18 @@ COMWorker::Work() noexcept
 {
 	SetThreadName("COM Worker");
 	COM com;
-	while (true) {
-		if (!running_flag.test_and_set()) {
-			return;
-		}
-		while (!spsc_buffer.empty()) {
-			std::function<void()> function;
-			spsc_buffer.pop(function);
+
+	std::unique_lock lock{mutex};
+	while (running_flag) {
+		while (!queue.empty()) {
+			auto function = std::move(queue.front());
+			queue.pop();
+
+			lock.unlock();
 			function();
+			lock.lock();
 		}
-		event.Wait(200);
+
+		cond.wait(lock);
 	}
 }

src/win32/ComWorker.hxx

@@ -20,19 +20,23 @@
 #ifndef MPD_WIN32_COM_WORKER_HXX
 #define MPD_WIN32_COM_WORKER_HXX
 
-#include "WinEvent.hxx"
+#include "thread/Cond.hxx"
 #include "thread/Future.hxx"
+#include "thread/Mutex.hxx"
 #include "thread/Thread.hxx"
 
-#include <boost/lockfree/spsc_queue.hpp>
+#include <functional>
+#include <queue>
 
 // Worker thread for all COM operation
 class COMWorker {
-	Thread thread{BIND_THIS_METHOD(Work)};
+	Mutex mutex;
+	Cond cond;
 
-	boost::lockfree::spsc_queue<std::function<void()>> spsc_buffer{32};
-	std::atomic_flag running_flag = true;
-	WinEvent event{};
+	std::queue<std::function<void()>> queue;
+	bool running_flag = true;
+
+	Thread thread{BIND_THIS_METHOD(Work)};
 
 public:
 	COMWorker() {
@@ -70,13 +74,15 @@ public:
 
 private:
 	void Finish() noexcept {
-		running_flag.clear();
-		event.Set();
+		const std::scoped_lock lock{mutex};
+		running_flag = false;
+		cond.notify_one();
 	}
 
 	void Push(const std::function<void()> &function) {
-		spsc_buffer.push(function);
-		event.Set();
+		const std::scoped_lock lock{mutex};
+		queue.push(function);
+		cond.notify_one();
 	}
 
 	void Work() noexcept;