Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.ServiceModel/System/ServiceModel/Channels/EncoderHelpers.cs

@@ -0,0 +1,65 @@
+// <copyright>
+// Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright> 
+
+namespace System.ServiceModel.Channels
+{
+    using System.ComponentModel;
+    using System.Runtime;
+    using System.Runtime.Serialization;
+    using System.ServiceModel.Configuration;
+    using System.Xml;
+
+    internal static class EncoderHelpers
+    {
+        internal static XmlDictionaryReaderQuotas GetBufferedReadQuotas(XmlDictionaryReaderQuotas encoderQuotas)
+        {
+            XmlDictionaryReaderQuotas bufferedReadQuotas = new XmlDictionaryReaderQuotas();
+            encoderQuotas.CopyTo(bufferedReadQuotas);
+
+            // now we have the quotas from the encoder, we need to update the values with the new quotas from the default read quotas. 
+            if (IsDefaultQuota(bufferedReadQuotas, XmlDictionaryReaderQuotaTypes.MaxStringContentLength))
+            {
+                bufferedReadQuotas.MaxStringContentLength = EncoderDefaults.BufferedReadDefaultMaxStringContentLength;
+            }
+
+            if (IsDefaultQuota(bufferedReadQuotas, XmlDictionaryReaderQuotaTypes.MaxArrayLength))
+            {
+                bufferedReadQuotas.MaxArrayLength = EncoderDefaults.BufferedReadDefaultMaxArrayLength;
+            }
+
+            if (IsDefaultQuota(bufferedReadQuotas, XmlDictionaryReaderQuotaTypes.MaxBytesPerRead))
+            {
+                bufferedReadQuotas.MaxBytesPerRead = EncoderDefaults.BufferedReadDefaultMaxBytesPerRead;
+            }
+
+            if (IsDefaultQuota(bufferedReadQuotas, XmlDictionaryReaderQuotaTypes.MaxNameTableCharCount))
+            {
+                bufferedReadQuotas.MaxNameTableCharCount = EncoderDefaults.BufferedReadDefaultMaxNameTableCharCount;
+            }
+
+            if (IsDefaultQuota(bufferedReadQuotas, XmlDictionaryReaderQuotaTypes.MaxDepth))
+            {
+                bufferedReadQuotas.MaxDepth = EncoderDefaults.BufferedReadDefaultMaxDepth;
+            }
+
+            return bufferedReadQuotas;
+        }
+
+        private static bool IsDefaultQuota(XmlDictionaryReaderQuotas quotas, XmlDictionaryReaderQuotaTypes quotaType)
+        {
+            switch (quotaType)
+            {
+                case XmlDictionaryReaderQuotaTypes.MaxDepth:
+                case XmlDictionaryReaderQuotaTypes.MaxStringContentLength:
+                case XmlDictionaryReaderQuotaTypes.MaxArrayLength:
+                case XmlDictionaryReaderQuotaTypes.MaxBytesPerRead:
+                case XmlDictionaryReaderQuotaTypes.MaxNameTableCharCount:
+                    return (quotas.ModifiedQuotas & quotaType) == 0x00;
+            }
+
+            Fx.Assert("invalid quota type.");
+            return false;
+        }
+    }
+}