Refactor IPC services to have commands into separate classes, fix readme url

Ryujinx.Core/OsHle/IpcServices/FspSrv/IStorage.cs

@@ -0,0 +1,52 @@
+using ChocolArm64.Memory;
+using Ryujinx.Core.OsHle.Ipc;
+using System.Collections.Generic;
+using System.IO;
+
+namespace Ryujinx.Core.OsHle.IpcServices.FspSrv
+{
+    class IStorage : IIpcService
+    {
+        private Dictionary<int, ServiceProcessRequest> m_Commands;
+
+        public IReadOnlyDictionary<int, ServiceProcessRequest> Commands => m_Commands;
+
+        private Stream BaseStream;
+
+        public IStorage(Stream BaseStream)
+        {
+            m_Commands = new Dictionary<int, ServiceProcessRequest>()
+            {
+                { 0, Read }
+            };
+
+            this.BaseStream = BaseStream;
+        }
+
+        public long Read(ServiceCtx Context)
+        {
+            long Offset = Context.RequestData.ReadInt64();
+            long Size   = Context.RequestData.ReadInt64();
+
+            if (Context.Request.ReceiveBuff.Count > 0)
+            {
+                IpcBuffDesc BuffDesc = Context.Request.ReceiveBuff[0];
+
+                //Use smaller length to avoid overflows.
+                if (Size > BuffDesc.Size)
+                {
+                    Size = BuffDesc.Size;
+                }
+
+                byte[] Data = new byte[Size];
+
+                BaseStream.Seek(Offset, SeekOrigin.Begin);
+                BaseStream.Read(Data, 0, Data.Length);
+
+                AMemoryHelper.WriteBytes(Context.Memory, BuffDesc.Position, Data);
+            }
+
+            return 0;
+        }
+    }
+}