1 files changed, 104 insertions, 0 deletions
diff --git a/src/mscorlib/shared/System/Diagnostics/Tracing/TraceLogging/TraceLoggingDataCollector.cs b/src/mscorlib/shared/System/Diagnostics/Tracing/TraceLogging/TraceLoggingDataCollector.cs
new file mode 100644
index 0000000000..04a047fb35
--- /dev/null
+++ b/src/mscorlib/shared/System/Diagnostics/Tracing/TraceLogging/TraceLoggingDataCollector.cs
@@ -0,0 +1,104 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Security;
+
+#if ES_BUILD_STANDALONE
+namespace Microsoft.Diagnostics.Tracing
+#else
+namespace System.Diagnostics.Tracing
+#endif
+{
+    /// <summary>
+    /// TraceLogging: Used when implementing a custom TraceLoggingTypeInfo.
+    /// The instance of this type is provided to the TypeInfo.WriteData method.
+    /// All operations are forwarded to the current thread's DataCollector.
+    /// Note that this abstraction would allow us to expose the custom
+    /// serialization system to partially-trusted code. If we end up not
+    /// making custom serialization public, or if we only expose it to
+    /// full-trust code, this abstraction is unnecessary (though it probably
+    /// doesn't hurt anything).
+    /// </summary>
+    internal unsafe class TraceLoggingDataCollector
+    {
+        internal static readonly TraceLoggingDataCollector Instance = new TraceLoggingDataCollector();
+
+        private TraceLoggingDataCollector()
+        {
+            return;
+        }
+
+        /// <summary>
+        /// Marks the start of a non-blittable array or enumerable.
+        /// </summary>
+        /// <returns>Bookmark to be passed to EndBufferedArray.</returns>
+        public int BeginBufferedArray()
+        {
+            return DataCollector.ThreadInstance.BeginBufferedArray();
+        }
+
+        /// <summary>
+        /// Marks the end of a non-blittable array or enumerable.
+        /// </summary>
+        /// <param name="bookmark">The value returned by BeginBufferedArray.</param>
+        /// <param name="count">The number of items in the array.</param>
+        public void EndBufferedArray(int bookmark, int count)
+        {
+            DataCollector.ThreadInstance.EndBufferedArray(bookmark, count);
+        }
+
+        /// <summary>
+        /// Adds the start of a group to the event.
+        /// This has no effect on the event payload, but is provided to allow
+        /// WriteMetadata and WriteData implementations to have similar
+        /// sequences of calls, allowing for easier verification of correctness.
+        /// </summary>
+        public TraceLoggingDataCollector AddGroup()
+        {
+            return this;
+        }
+
+        public void AddScalar(PropertyValue value)
+        {
+            var scalar = value.ScalarValue;
+            DataCollector.ThreadInstance.AddScalar(&scalar, value.ScalarLength);
+        }
+
+        /// <summary>
+        /// Adds an Int64 value to the event payload.
+        /// </summary>
+        /// <param name="value">Value to be added.</param>
+        public void AddScalar(long value)
+        {
+            DataCollector.ThreadInstance.AddScalar(&value, sizeof(long));
+        }
+
+        /// <summary>
+        /// Adds a Double value to the event payload.
+        /// </summary>
+        /// <param name="value">Value to be added.</param>
+        public void AddScalar(double value)
+        {
+            DataCollector.ThreadInstance.AddScalar(&value, sizeof(double));
+        }
+
+        /// <summary>
+        /// Adds a counted String value to the event payload.
+        /// </summary>
+        /// <param name="value">
+        /// Value to be added. A null value is treated as a zero-length string.
+        /// </param>
+        public void AddBinary(string value)
+        {
+            DataCollector.ThreadInstance.AddBinary(value, value == null ? 0 : value.Length * 2);
+        }
+
+        public void AddArray(PropertyValue value, int elementSize)
+        {
+            Array array = (Array)value.ReferenceValue;
+            DataCollector.ThreadInstance.AddArray(array, array == null ? 0 : array.Length, elementSize);
+        }
+    }
+}