1 files changed, 188 insertions, 0 deletions
diff --git a/Ryujinx.Audio.Renderer/Utils/SpanIOHelper.cs b/Ryujinx.Audio.Renderer/Utils/SpanIOHelper.cs
new file mode 100644
index 00000000..214927bc
--- /dev/null
+++ b/Ryujinx.Audio.Renderer/Utils/SpanIOHelper.cs
@@ -0,0 +1,188 @@
+//
+// 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 System;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Audio.Renderer.Utils
+{
+    /// <summary>
+    /// Helper for IO operations on <see cref="Span{T}"/> and <see cref="Memory{T}"/>.
+    /// </summary>
+    public static class SpanIOHelper
+    {
+        /// <summary>
+        /// Write the given data to the given backing <see cref="Memory{T}"/> and move cursor after the written data.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="backingMemory">The backing <see cref="Memory{T}"/> to store the data.</param>
+        /// <param name="data">The data to write to the backing <see cref="Memory{T}"/>.</param>
+        public static void Write<T>(ref Memory<byte> backingMemory, ref T data) where T : unmanaged
+        {
+            int size = Unsafe.SizeOf<T>();
+
+            if (size > backingMemory.Length)
+            {
+                throw new ArgumentOutOfRangeException();
+            }
+
+            MemoryMarshal.Write<T>(backingMemory.Span.Slice(0, size), ref data);
+
+            backingMemory = backingMemory.Slice(size);
+        }
+
+        /// <summary>
+        /// Write the given data to the given backing <see cref="Span{T}"/> and move cursor after the written data.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="backingMemory">The backing <see cref="Span{T}"/> to store the data.</param>
+        /// <param name="data">The data to write to the backing <see cref="Span{T}"/>.</param>
+        public static void Write<T>(ref Span<byte> backingMemory, ref T data) where T : unmanaged
+        {
+            int size = Unsafe.SizeOf<T>();
+
+            if (size > backingMemory.Length)
+            {
+                throw new ArgumentOutOfRangeException();
+            }
+
+            MemoryMarshal.Write<T>(backingMemory.Slice(0, size), ref data);
+
+            backingMemory = backingMemory.Slice(size);
+        }
+
+        /// <summary>
+        /// Get a <see cref="Span{T}"/> out of a <paramref name="backingMemory"/> and move cursor after T size.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="backingMemory">The backing <see cref="Memory{T}"/> to get a <see cref="Span{T}"/> from.</param>
+        /// <returns>A <see cref="Span{T}"/> from backing <see cref="Memory{T}"/>.</returns>
+        public static Span<T> GetWriteRef<T>(ref Memory<byte> backingMemory) where T : unmanaged
+        {
+            int size = Unsafe.SizeOf<T>();
+
+            if (size > backingMemory.Length)
+            {
+                throw new ArgumentOutOfRangeException();
+            }
+
+            Span<T> result = MemoryMarshal.Cast<byte, T>(backingMemory.Span.Slice(0, size));
+
+            backingMemory = backingMemory.Slice(size);
+
+            return result;
+        }
+
+        /// <summary>
+        /// Get a <see cref="Span{T}"/> out of a backingMemory and move cursor after T size.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="backingMemory">The backing <see cref="Span{T}"/> to get a <see cref="Span{T}"/> from.</param>
+        /// <returns>A <see cref="Span{T}"/> from backing <see cref="Span{T}"/>.</returns>
+        public static Span<T> GetWriteRef<T>(ref Span<byte> backingMemory) where T : unmanaged
+        {
+            int size = Unsafe.SizeOf<T>();
+
+            if (size > backingMemory.Length)
+            {
+                throw new ArgumentOutOfRangeException();
+            }
+
+            Span<T> result = MemoryMarshal.Cast<byte, T>(backingMemory.Slice(0, size));
+
+            backingMemory = backingMemory.Slice(size);
+
+            return result;
+        }
+
+        /// <summary>
+        /// Read data from the given backing <see cref="ReadOnlyMemory{T}"/> and move cursor after the read data.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="backingMemory">The backing <see cref="ReadOnlyMemory{T}"/> to read data from.</param>
+        /// <returns>Return the read data.</returns>
+        public static T Read<T>(ref ReadOnlyMemory<byte> backingMemory) where T : unmanaged
+        {
+            int size = Unsafe.SizeOf<T>();
+
+            if (size > backingMemory.Length)
+            {
+                throw new ArgumentOutOfRangeException();
+            }
+
+            T result = MemoryMarshal.Read<T>(backingMemory.Span.Slice(0, size));
+
+            backingMemory = backingMemory.Slice(size);
+
+            return result;
+        }
+
+        /// <summary>
+        /// Read data from the given backing <see cref="ReadOnlySpan{T}"/> and move cursor after the read data.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="backingMemory">The backing <see cref="ReadOnlySpan{T}"/> to read data from.</param>
+        /// <returns>Return the read data.</returns>
+        public static T Read<T>(ref ReadOnlySpan<byte> backingMemory) where T : unmanaged
+        {
+            int size = Unsafe.SizeOf<T>();
+
+            if (size > backingMemory.Length)
+            {
+                throw new ArgumentOutOfRangeException();
+            }
+
+            T result = MemoryMarshal.Read<T>(backingMemory.Slice(0, size));
+
+            backingMemory = backingMemory.Slice(size);
+
+            return result;
+        }
+
+        /// <summary>
+        /// Extract a <see cref="Memory{T}"/> at the given index.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="memory">The <see cref="Memory{T}"/> to extract the data from.</param>
+        /// <param name="id">The id in the provided memory.</param>
+        /// <param name="count">The max allowed count. (for bound checking of the id in debug mode)</param>
+        /// <returns>a <see cref="Memory{T}"/> at the given id.</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static Memory<T> GetMemory<T>(Memory<T> memory, int id, uint count) where T : unmanaged
+        {
+            Debug.Assert(id >= 0 && id < count);
+
+            return memory.Slice(id, 1);
+        }
+
+        /// <summary>
+        /// Extract a ref T at the given index.
+        /// </summary>
+        /// <typeparam name="T">The data type.</typeparam>
+        /// <param name="memory">The <see cref="Memory{T}"/> to extract the data from.</param>
+        /// <param name="id">The id in the provided memory.</param>
+        /// <param name="count">The max allowed count. (for bound checking of the id in debug mode)</param>
+        /// <returns>a ref T at the given id.</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static ref T GetFromMemory<T>(Memory<T> memory, int id, uint count) where T : unmanaged
+        {
+            return ref GetMemory(memory, id, count).Span[0];
+        }
+    }
+}