Initial checkin of gRPC to third_party/

third_party/grpc/src/csharp/Grpc.Core/Internal/CStringSafeHandle.cs

 #region Copyright notice and license
-// Protocol Buffers - Google's data interchange format
-// Copyright 2015 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
+// Copyright 2015-2016, Google Inc.
+// All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #endregion
-    
-namespace Google.Protobuf
+using System;
+using System.Runtime.InteropServices;
+using System.Threading.Tasks;
+
+namespace Grpc.Core.Internal
 {
-    // Just a sample enum with positive and negative values to be used in tests.
-    internal enum SampleEnum
+    /// <summary>
+    /// Owned char* object.
+    /// </summary>
+    internal class CStringSafeHandle : SafeHandleZeroIsInvalid
     {
-        NegativeValue = -2,
-        None = 0,
-        PositiveValue = 3
+        static readonly NativeMethods Native = NativeMethods.Get();
+
+        private CStringSafeHandle()
+        {
+        }
+
+        public string GetValue()
+        {
+            return Marshal.PtrToStringAnsi(handle);
+        }
+
+        protected override bool ReleaseHandle()
+        {
+            Native.gprsharp_free(handle);
+            return true;
+        }
     }
 }