1 files changed, 237 insertions, 0 deletions
diff --git a/Ryujinx.Audio.Renderer/Server/Splitter/SplitterState.cs b/Ryujinx.Audio.Renderer/Server/Splitter/SplitterState.cs
new file mode 100644
index 00000000..f86e75dd
--- /dev/null
+++ b/Ryujinx.Audio.Renderer/Server/Splitter/SplitterState.cs
@@ -0,0 +1,237 @@
+//
+// Copyright (c) 2019-2020 Ryujinx
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+//
+using Ryujinx.Audio.Renderer.Parameter;
+using System;
+using System.Buffers;
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Audio.Renderer.Server.Splitter
+{
+    /// <summary>
+    /// Server state for a splitter.
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, Size = 0x20, Pack = Alignment)]
+    public struct SplitterState
+    {
+        public const int Alignment = 0x10;
+
+        /// <summary>
+        /// The unique id of this <see cref="SplitterState"/>.
+        /// </summary>
+        public int Id;
+
+        /// <summary>
+        /// Target sample rate to use on the splitter.
+        /// </summary>
+        public uint SampleRate;
+
+        /// <summary>
+        /// Count of splitter destinations (<see cref="SplitterDestination"/>).
+        /// </summary>
+        public int DestinationCount;
+
+        /// <summary>
+        /// Set to true if the splitter has a new connection.
+        /// </summary>
+        [MarshalAs(UnmanagedType.I1)]
+        public bool HasNewConnection;
+
+        /// <summary>
+        /// Linked list of <see cref="SplitterDestination"/>.
+        /// </summary>
+        private unsafe SplitterDestination* _destinationsData;
+
+        /// <summary>
+        /// Span to the first element of the linked list of <see cref="SplitterDestination"/>.
+        /// </summary>
+        public Span<SplitterDestination> Destinations
+        {
+            get
+            {
+                unsafe
+                {
+                    return (IntPtr)_destinationsData != IntPtr.Zero ? new Span<SplitterDestination>(_destinationsData, 1) : Span<SplitterDestination>.Empty;
+                }
+            }
+        }
+
+        /// <summary>
+        /// Create a new <see cref="SplitterState"/>.
+        /// </summary>
+        /// <param name="id">The unique id of this <see cref="SplitterState"/>.</param>
+        public SplitterState(int id) : this()
+        {
+            Id = id;
+        }
+
+        public Span<SplitterDestination> GetData(int index)
+        {
+            int i = 0;
+
+            Span<SplitterDestination> result = Destinations;
+
+            while (i < index)
+            {
+                if (result.IsEmpty)
+                {
+                    break;
+                }
+
+                result = result[0].Next;
+                i++;
+            }
+
+            return result;
+        }
+
+        /// <summary>
+        /// Clear the new connection flag.
+        /// </summary>
+        public void ClearNewConnectionFlag()
+        {
+            HasNewConnection = false;
+        }
+
+        /// <summary>
+        /// Utility function to apply a given <see cref="SpanAction{T, TArg}"/> to all <see cref="Destinations"/>.
+        /// </summary>
+        /// <param name="action">The action to execute on each elements.</param>
+        private void ForEachDestination(SpanAction<SplitterDestination, int> action)
+        {
+            Span<SplitterDestination> temp = Destinations;
+
+            int i = 0;
+
+            while (true)
+            {
+                if (temp.IsEmpty)
+                {
+                    break;
+                }
+
+                Span<SplitterDestination> next = temp[0].Next;
+
+                action.Invoke(temp, i++);
+
+                temp = next;
+            }
+        }
+
+        /// <summary>
+        /// Update the <see cref="SplitterState"/> from user parameter.
+        /// </summary>
+        /// <param name="context">The splitter context.</param>
+        /// <param name="parameter">The user parameter.</param>
+        /// <param name="input">The raw input data after the <paramref name="parameter"/>.</param>
+        public void Update(SplitterContext context, ref SplitterInParameter parameter, ReadOnlySpan<byte> input)
+        {
+            ClearLinks();
+
+            int destinationCount;
+
+            if (context.IsBugFixed)
+            {
+                destinationCount = parameter.DestinationCount;
+            }
+            else
+            {
+                destinationCount = Math.Min(context.GetDestinationCountPerStateForCompatibility(), parameter.DestinationCount);
+            }
+
+            if (destinationCount > 0)
+            {
+                ReadOnlySpan<int> destinationIds = MemoryMarshal.Cast<byte, int>(input);
+
+                Memory<SplitterDestination> destination = context.GetDestinationMemory(destinationIds[0]);
+
+                SetDestination(ref destination.Span[0]);
+
+                DestinationCount = destinationCount;
+
+                for (int i = 1; i < destinationCount; i++)
+                {
+                    Memory<SplitterDestination> nextDestination = context.GetDestinationMemory(destinationIds[i]);
+
+                    destination.Span[0].Link(ref nextDestination.Span[0]);
+                    destination = nextDestination;
+                }
+            }
+
+            Debug.Assert(parameter.Id == Id);
+
+            if (parameter.Id == Id)
+            {
+                SampleRate = parameter.SampleRate;
+                HasNewConnection = true;
+            }
+        }
+
+        /// <summary>
+        /// Set the head of the linked list of <see cref="Destinations"/>.
+        /// </summary>
+        /// <param name="newValue">A reference to a <see cref="SplitterDestination"/>.</param>
+        public void SetDestination(ref SplitterDestination newValue)
+        {
+            unsafe
+            {
+                fixed (SplitterDestination* newValuePtr = &newValue)
+                {
+                    _destinationsData = newValuePtr;
+                }
+            }
+        }
+
+        /// <summary>
+        /// Update the internal state of this instance.
+        /// </summary>
+        public void UpdateInternalState()
+        {
+            ForEachDestination((destination, _) => destination[0].UpdateInternalState());
+        }
+
+        /// <summary>
+        /// Clear all links from the <see cref="Destinations"/>.
+        /// </summary>
+        public void ClearLinks()
+        {
+            ForEachDestination((destination, _) => destination[0].Unlink());
+
+            unsafe
+            {
+                _destinationsData = (SplitterDestination*)IntPtr.Zero;
+            }
+        }
+
+        /// <summary>
+        /// Initialize a given <see cref="Span{SplitterState}"/>.
+        /// </summary>
+        /// <param name="splitters">All the <see cref="SplitterState"/> to initialize.</param>
+        public static void InitializeSplitters(Span<SplitterState> splitters)
+        {
+            foreach (ref SplitterState splitter in splitters)
+            {
+                unsafe
+                {
+                    splitter._destinationsData = (SplitterDestination*)IntPtr.Zero;
+                }
+
+                splitter.DestinationCount = 0;
+            }
+        }
+    }
+}