Fix threadsafety in DataServiceClient EntityTracker's internal dicti…

…onary (#1200)

* Change Dictionary<> objects in EntityTracker to use thread-safe ConcurrentDictionary<> objects instead.

* Convert tabs to spaces.

* More tabs to spaces.

* Fix editor removing spaces.

* Fix spaces.

* Mimic IDictionary Add() duplicate exception semantics.

* Fix thread safety

src/Microsoft.OData.Client/DictionaryExtensions.cs

@@ -8,11 +8,12 @@ namespace Microsoft.OData.Client
 {
     using System;
     using System.Collections.Generic;
+    using System.Collections.Concurrent;
     using System.Diagnostics;
     using System.Diagnostics.CodeAnalysis;
 
     /// <summary>
-    /// Useful extension methods for IDictionary
+    /// Useful extension methods for IDictionary and ConcurrentDictionary
     /// </summary>
     internal static class DictionaryExtensions
     {
@@ -54,7 +55,7 @@ internal static void SetRange<TKey, TValue>(this IDictionary<TKey, TValue> dicti
             }
         }
 
-#if PORTABLELIB
+#if PORTABLELIB && WINDOWSPHONE
         /// <summary>
         /// Try to add a key/value pair to the dictionary and returns true if the key was added, false if it was already present.
         /// The difference with Add is that it will not throw <see cref="ArgumentException"/> if the key is already present.
@@ -85,6 +86,23 @@ internal static bool TryAdd<TKey, TValue>(this IDictionary<TKey, TValue> dict, T
 
             return false;
         }
+#else
+        /// <summary>
+        /// Convenience function that wraps ConcurrentDictionary.TryAdd() to allow same signature as IDictionary
+        /// </summary>
+        public static void Add<TKey, TValue>(this ConcurrentDictionary<TKey, TValue> self, TKey key, TValue value)
+        {
+            if (!self.TryAdd(key, value))
+                throw new ArgumentException("Argument_AddingDuplicate");
+        }
+
+        /// <summary>
+        /// Convenience function for ConcurrentDictionary to allow same signature as IDictionary
+        /// </summary>
+        public static bool Remove<TKey, TValue>(this ConcurrentDictionary<TKey, TValue> self, TKey key)
+        {
+            return ((IDictionary<TKey, TValue>)self).Remove(key);
+        }
 #endif
     }
 }

src/Microsoft.OData.Client/EntityTracker.cs

@@ -9,6 +9,7 @@ namespace Microsoft.OData.Client
     #region Namespaces
     using System;
     using System.Collections.Generic;
+    using System.Collections.Concurrent;
     using System.Diagnostics;
     using System.Diagnostics.CodeAnalysis;
     using System.Linq;
@@ -26,14 +27,28 @@ public class EntityTracker : EntityTrackerBase
 
         #region Resource state management
 
+    #if PORTABLELIB && WINDOWSPHONE
         /// <summary>Set of tracked resources</summary>
         private Dictionary<object, EntityDescriptor> entityDescriptors = new Dictionary<object, EntityDescriptor>(EqualityComparer<object>.Default);
-
+    #else
+        /// <summary>Set of tracked resources</summary>
+        private ConcurrentDictionary<object, EntityDescriptor> entityDescriptors = new ConcurrentDictionary<object, EntityDescriptor>(EqualityComparer<object>.Default);
+    #endif
+    #if PORTABLELIB && WINDOWSPHONE
         /// <summary>Set of tracked resources by Identity</summary>
         private Dictionary<Uri, EntityDescriptor> identityToDescriptor;
+    #else
+        /// <summary>Set of tracked resources by Identity</summary>
+        private ConcurrentDictionary<Uri, EntityDescriptor> identityToDescriptor;
+    #endif
 
+    #if PORTABLELIB && WINDOWSPHONE
         /// <summary>Set of tracked bindings</summary>
         private Dictionary<LinkDescriptor, LinkDescriptor> bindings;
+    #else
+        /// <summary>Set of tracked bindings</summary>
+        private ConcurrentDictionary<LinkDescriptor, LinkDescriptor> bindings;
+    #endif
 
         /// <summary>change order</summary>
         private uint nextChange;
@@ -525,16 +540,24 @@ private void EnsureIdentityToResource()
         {
             if (null == this.identityToDescriptor)
             {
+            #if PORTABLELIB && WINDOWSPHONE
                 System.Threading.Interlocked.CompareExchange(ref this.identityToDescriptor, new Dictionary<Uri, EntityDescriptor>(EqualityComparer<Uri>.Default), null);
-            }
-        }
+            #else
+                System.Threading.Interlocked.CompareExchange(ref this.identityToDescriptor, new ConcurrentDictionary<Uri, EntityDescriptor>(EqualityComparer<Uri>.Default), null);
+            #endif
+			}
+		}
 
         /// <summary>create this.bindings when necessary</summary>
         private void EnsureLinkBindings()
         {
             if (null == this.bindings)
             {
+            #if PORTABLELIB && WINDOWSPHONE
                 System.Threading.Interlocked.CompareExchange(ref this.bindings, new Dictionary<LinkDescriptor, LinkDescriptor>(LinkDescriptor.EquivalenceComparer), null);
+            #else
+                System.Threading.Interlocked.CompareExchange(ref this.bindings, new ConcurrentDictionary<LinkDescriptor, LinkDescriptor>(LinkDescriptor.EquivalenceComparer), null);
+            #endif
             }
         }