1 files changed, 97 insertions, 0 deletions
diff --git a/Firebase/Utilities/Network/GULMutableDictionary.m b/Firebase/Utilities/Network/GULMutableDictionary.m
new file mode 100644
index 0000000..d281eb4
--- /dev/null
+++ b/Firebase/Utilities/Network/GULMutableDictionary.m
@@ -0,0 +1,97 @@
+// Copyright 2017 Google
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import "Private/GULMutableDictionary.h"
+
+@implementation GULMutableDictionary {
+  /// The mutable dictionary.
+  NSMutableDictionary *_objects;
+
+  /// Serial synchronization queue. All reads should use dispatch_sync, while writes use
+  /// dispatch_async.
+  dispatch_queue_t _queue;
+}
+
+- (instancetype)init {
+  self = [super init];
+
+  if (self) {
+    _objects = [[NSMutableDictionary alloc] init];
+    _queue = dispatch_queue_create("GULMutableDictionary", DISPATCH_QUEUE_SERIAL);
+  }
+
+  return self;
+}
+
+- (NSString *)description {
+  __block NSString *description;
+  dispatch_sync(_queue, ^{
+    description = self->_objects.description;
+  });
+  return description;
+}
+
+- (id)objectForKey:(id)key {
+  __block id object;
+  dispatch_sync(_queue, ^{
+    object = self->_objects[key];
+  });
+  return object;
+}
+
+- (void)setObject:(id)object forKey:(id<NSCopying>)key {
+  dispatch_async(_queue, ^{
+    self->_objects[key] = object;
+  });
+}
+
+- (void)removeObjectForKey:(id)key {
+  dispatch_async(_queue, ^{
+    [self->_objects removeObjectForKey:key];
+  });
+}
+
+- (void)removeAllObjects {
+  dispatch_async(_queue, ^{
+    [self->_objects removeAllObjects];
+  });
+}
+
+- (NSUInteger)count {
+  __block NSUInteger count;
+  dispatch_sync(_queue, ^{
+    count = self->_objects.count;
+  });
+  return count;
+}
+
+- (id)objectForKeyedSubscript:(id<NSCopying>)key {
+  // The method this calls is already synchronized.
+  return [self objectForKey:key];
+}
+
+- (void)setObject:(id)obj forKeyedSubscript:(id<NSCopying>)key {
+  // The method this calls is already synchronized.
+  [self setObject:obj forKey:key];
+}
+
+- (NSDictionary *)dictionary {
+  __block NSDictionary *dictionary;
+  dispatch_sync(_queue, ^{
+    dictionary = [self->_objects copy];
+  });
+  return dictionary;
+}
+
+@end