Add missing source file

Author: aacuevas

OpenEphys.Onix1/EquivalentDataSource.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace OpenEphys.Onix1
+{
+    /// <summary>
+    /// Specifies a device class as equivalent to another for data production
+    /// </summary>
+    /// <remarks>
+    /// This attribute must be used on the static classes that specify
+    /// the device IDs and name converters to mark it as equivalent to
+    /// another. 
+    /// 
+    /// This will be used only for data production and name converters
+    /// 
+    /// The method <see cref="ContextHelper.CheckDeviceType(Type, Type)"/>
+    /// can be used to check for type or equivalent type matching
+    /// </remarks>
+    [AttributeUsage(AttributeTargets.Class, AllowMultiple = true, Inherited = false)]
+    public sealed class EquivalentDataSource : Attribute
+    {
+        /// <summary>
+        /// The original type the tagged class is equivalent to
+        /// </summary>
+        public Type BaseType { get; }
+
+        public EquivalentDataSource(Type baseType)
+        {
+            BaseType = baseType;
+        }
+    }
+}