Initial checkin of gRPC to third_party/

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

+#region Copyright notice and license
+// 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
+using System;
+using System.Runtime.InteropServices;
+using System.Threading.Tasks;
+using Grpc.Core.Profiling;
+
+namespace Grpc.Core.Internal
+{
+    /// <summary>
+    /// grpc_metadata_array from <c>grpc/grpc.h</c>
+    /// </summary>
+    internal class MetadataArraySafeHandle : SafeHandleZeroIsInvalid
+    {
+        static readonly NativeMethods Native = NativeMethods.Get();
+
+        private MetadataArraySafeHandle()
+        {
+        }
+            
+        public static MetadataArraySafeHandle Create(Metadata metadata)
+        {
+            using (Profilers.ForCurrentThread().NewScope("MetadataArraySafeHandle.Create"))
+            {
+                // TODO(jtattermusch): we might wanna check that the metadata is readonly 
+                var metadataArray = Native.grpcsharp_metadata_array_create(new UIntPtr((ulong)metadata.Count));
+                for (int i = 0; i < metadata.Count; i++)
+                {
+                    var valueBytes = metadata[i].GetSerializedValueUnsafe();
+                    Native.grpcsharp_metadata_array_add(metadataArray, metadata[i].Key, valueBytes, new UIntPtr((ulong)valueBytes.Length));
+                }
+                return metadataArray;
+            }
+        }
+
+        /// <summary>
+        /// Reads metadata from pointer to grpc_metadata_array
+        /// </summary>
+        public static Metadata ReadMetadataFromPtrUnsafe(IntPtr metadataArray)
+        {
+            if (metadataArray == IntPtr.Zero)
+            {
+                return null;
+            }
+
+            ulong count = Native.grpcsharp_metadata_array_count(metadataArray).ToUInt64();
+
+            var metadata = new Metadata();
+            for (ulong i = 0; i < count; i++)
+            {
+                var index = new UIntPtr(i);
+                string key = Marshal.PtrToStringAnsi(Native.grpcsharp_metadata_array_get_key(metadataArray, index));
+                var bytes = new byte[Native.grpcsharp_metadata_array_get_value_length(metadataArray, index).ToUInt64()];
+                Marshal.Copy(Native.grpcsharp_metadata_array_get_value(metadataArray, index), bytes, 0, bytes.Length);
+                metadata.Add(Metadata.Entry.CreateUnsafe(key, bytes));
+            }
+            return metadata;
+        }
+
+        internal IntPtr Handle
+        {
+            get
+            {
+                return handle;
+            }
+        }
+
+        protected override bool ReleaseHandle()
+        {
+            Native.grpcsharp_metadata_array_destroy_full(handle);
+            return true;
+        }
+    }
+}