Initial checkin of gRPC to third_party/

third_party/grpc/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs

Index: third_party/grpc/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
diff --git a/third_party/grpc/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs b/third_party/grpc/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
new file mode 100644
index 0000000000000000000000000000000000000000..76bf04ce8b2091c56b00d5104db26757dc2caf77
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+++ b/third_party/grpc/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
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+#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;
+
+namespace Grpc.Core.Utils
+{
+    /// <summary>
+    /// Utility methods to simplify checking preconditions in the code.
+    /// </summary>
+    public static class GrpcPreconditions
+    {
+        /// <summary>
+        /// Throws <see cref="ArgumentException"/> if condition is false.
+        /// </summary>
+        /// <param name="condition">The condition.</param>
+        public static void CheckArgument(bool condition)
+        {
+            if (!condition)
+            {
+                throw new ArgumentException();
+            }
+        }
+
+        /// <summary>
+        /// Throws <see cref="ArgumentException"/> with given message if condition is false.
+        /// </summary>
+        /// <param name="condition">The condition.</param>
+        /// <param name="errorMessage">The error message.</param>
+        public static void CheckArgument(bool condition, string errorMessage)
+        {
+            if (!condition)
+            {
+                throw new ArgumentException(errorMessage);
+            }
+        }
+
+        /// <summary>
+        /// Throws <see cref="ArgumentNullException"/> if reference is null.
+        /// </summary>
+        /// <param name="reference">The reference.</param>
+        public static T CheckNotNull<T>(T reference)
+        {
+            if (reference == null)
+            {
+                throw new ArgumentNullException();
+            }
+            return reference;
+        }
+
+        /// <summary>
+        /// Throws <see cref="ArgumentNullException"/> if reference is null.
+        /// </summary>
+        /// <param name="reference">The reference.</param>
+        /// <param name="paramName">The parameter name.</param>
+        public static T CheckNotNull<T>(T reference, string paramName)
+        {
+            if (reference == null)
+            {
+                throw new ArgumentNullException(paramName);
+            }
+            return reference;
+        }
+
+        /// <summary>
+        /// Throws <see cref="InvalidOperationException"/> if condition is false.
+        /// </summary>
+        /// <param name="condition">The condition.</param>
+        public static void CheckState(bool condition)
+        {
+            if (!condition)
+            {
+                throw new InvalidOperationException();
+            }
+        }
+
+        /// <summary>
+        /// Throws <see cref="InvalidOperationException"/> with given message if condition is false.
+        /// </summary>
+        /// <param name="condition">The condition.</param>
+        /// <param name="errorMessage">The error message.</param>
+        public static void CheckState(bool condition, string errorMessage)
+        {
+            if (!condition)
+            {
+                throw new InvalidOperationException(errorMessage);
+            }
+        }
+    }
+}