1 files changed, 176 insertions, 0 deletions
diff --git a/src/Ryujinx.Audio.Backends.SDL2/SDL2HardwareDeviceDriver.cs b/src/Ryujinx.Audio.Backends.SDL2/SDL2HardwareDeviceDriver.cs
new file mode 100644
index 00000000..b190b4c8
--- /dev/null
+++ b/src/Ryujinx.Audio.Backends.SDL2/SDL2HardwareDeviceDriver.cs
@@ -0,0 +1,176 @@
+using Ryujinx.Audio.Common;
+using Ryujinx.Audio.Integration;
+using Ryujinx.Common.Logging;
+using Ryujinx.Memory;
+using Ryujinx.SDL2.Common;
+using System;
+using System.Collections.Concurrent;
+using System.Threading;
+
+using static Ryujinx.Audio.Integration.IHardwareDeviceDriver;
+using static SDL2.SDL;
+
+namespace Ryujinx.Audio.Backends.SDL2
+{
+    public class SDL2HardwareDeviceDriver : IHardwareDeviceDriver
+    {
+        private readonly ManualResetEvent _updateRequiredEvent;
+        private readonly ManualResetEvent _pauseEvent;
+        private readonly ConcurrentDictionary<SDL2HardwareDeviceSession, byte> _sessions;
+
+        public SDL2HardwareDeviceDriver()
+        {
+            _updateRequiredEvent = new ManualResetEvent(false);
+            _pauseEvent = new ManualResetEvent(true);
+            _sessions = new ConcurrentDictionary<SDL2HardwareDeviceSession, byte>();
+
+            SDL2Driver.Instance.Initialize();
+        }
+
+        public static bool IsSupported => IsSupportedInternal();
+
+        private static bool IsSupportedInternal()
+        {
+            uint device = OpenStream(SampleFormat.PcmInt16, Constants.TargetSampleRate, Constants.ChannelCountMax, Constants.TargetSampleCount, null);
+
+            if (device != 0)
+            {
+                SDL_CloseAudioDevice(device);
+            }
+
+            return device != 0;
+        }
+
+        public ManualResetEvent GetUpdateRequiredEvent()
+        {
+            return _updateRequiredEvent;
+        }
+
+        public ManualResetEvent GetPauseEvent()
+        {
+            return _pauseEvent;
+        }
+
+        public IHardwareDeviceSession OpenDeviceSession(Direction direction, IVirtualMemoryManager memoryManager, SampleFormat sampleFormat, uint sampleRate, uint channelCount, float volume)
+        {
+            if (channelCount == 0)
+            {
+                channelCount = 2;
+            }
+
+            if (sampleRate == 0)
+            {
+                sampleRate = Constants.TargetSampleRate;
+            }
+
+            if (direction != Direction.Output)
+            {
+                throw new NotImplementedException("Input direction is currently not implemented on SDL2 backend!");
+            }
+
+            SDL2HardwareDeviceSession session = new SDL2HardwareDeviceSession(this, memoryManager, sampleFormat, sampleRate, channelCount, volume);
+
+            _sessions.TryAdd(session, 0);
+
+            return session;
+        }
+
+        internal bool Unregister(SDL2HardwareDeviceSession session)
+        {
+            return _sessions.TryRemove(session, out _);
+        }
+
+        private static SDL_AudioSpec GetSDL2Spec(SampleFormat requestedSampleFormat, uint requestedSampleRate, uint requestedChannelCount, uint sampleCount)
+        {
+            return new SDL_AudioSpec
+            {
+                channels = (byte)requestedChannelCount,
+                format = GetSDL2Format(requestedSampleFormat),
+                freq = (int)requestedSampleRate,
+                samples = (ushort)sampleCount
+            };
+        }
+
+        internal static ushort GetSDL2Format(SampleFormat format)
+        {
+            return format switch
+            {
+                SampleFormat.PcmInt8 => AUDIO_S8,
+                SampleFormat.PcmInt16 => AUDIO_S16,
+                SampleFormat.PcmInt32 => AUDIO_S32,
+                SampleFormat.PcmFloat => AUDIO_F32,
+                _ => throw new ArgumentException($"Unsupported sample format {format}"),
+            };
+        }
+
+        internal static uint OpenStream(SampleFormat requestedSampleFormat, uint requestedSampleRate, uint requestedChannelCount, uint sampleCount, SDL_AudioCallback callback)
+        {
+            SDL_AudioSpec desired = GetSDL2Spec(requestedSampleFormat, requestedSampleRate, requestedChannelCount, sampleCount);
+
+            desired.callback = callback;
+
+            uint device = SDL_OpenAudioDevice(IntPtr.Zero, 0, ref desired, out SDL_AudioSpec got, 0);
+
+            if (device == 0)
+            {
+                Logger.Error?.Print(LogClass.Application, 
+                    $"SDL2 open audio device initialization failed with error \"{SDL_GetError()}\"");
+
+                return 0;
+            }
+
+            bool isValid = got.format == desired.format && got.freq == desired.freq && got.channels == desired.channels;
+
+            if (!isValid)
+            {
+                Logger.Error?.Print(LogClass.Application, "SDL2 open audio device is not valid");
+                SDL_CloseAudioDevice(device);
+
+                return 0;
+            }
+
+            return device;
+        }
+
+        public void Dispose()
+        {
+            Dispose(true);
+        }
+
+        protected virtual void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                foreach (SDL2HardwareDeviceSession session in _sessions.Keys)
+                {
+                    session.Dispose();
+                }
+
+                SDL2Driver.Instance.Dispose();
+
+                _pauseEvent.Dispose();
+            }
+        }
+
+        public bool SupportsSampleRate(uint sampleRate)
+        {
+            return true;
+        }
+
+        public bool SupportsSampleFormat(SampleFormat sampleFormat)
+        {
+            return sampleFormat != SampleFormat.PcmInt24;
+        }
+
+        public bool SupportsChannelCount(uint channelCount)
+        {
+            return true;
+        }
+
+        public bool SupportsDirection(Direction direction)
+        {
+            // TODO: add direction input when supported.
+            return direction == Direction.Output;
+        }
+    }
+}