Adding audio interface part 1

include/audio/audio_device.hpp

@@ -0,0 +1,31 @@
+#pragma once
+#include <array>
+
+#include "config.hpp"
+#include "helpers.hpp"
+#include "ring_buffer.hpp"
+
+class AudioDeviceInterface {
+  protected:
+	using Samples = Common::RingBuffer<s16, 0x2000 * 2>;
+	Samples* samples = nullptr;
+
+	const AudioDeviceConfig& audioSettings;
+
+  public:
+	AudioDeviceInterface(Samples* samples, const AudioDeviceConfig& audioSettings) : samples(samples), audioSettings(audioSettings) {}
+
+	// Store the last stereo sample we output. We play this when underruning to avoid pops.
+	// TODO: Make this protected again before merging!!!
+	std::array<s16, 2> lastStereoSample{};
+
+	bool running = false;
+	Samples* getSamples() { return samples; }
+
+	// If safe is on, we create a null audio device
+	virtual void init(Samples& samples, bool safe = false) = 0;
+	virtual void close() = 0;
+
+	virtual void start() = 0;
+	virtual void stop() = 0;
+};