Commit

Carthage/Checkouts/TrueTime.swift/Sources/GCDLock.swift

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+//
+//  GCDLock.swift
+//  TrueTime
+//
+//  Created by Michael Sanders on 10/27/16.
+//  Copyright © 2016 Instacart. All rights reserved.
+//
+
+import Foundation
+
+final class GCDLock<Value> {
+    var value: Value
+    let queue = DispatchQueue(label: "")
+    init(value: Value) {
+        self.value = value
+    }
+
+    func read() -> Value {
+        var value: Value?
+        queue.sync {
+            value = self.value
+        }
+        return value!
+    }
+
+    func write(_ newValue: Value) {
+        queue.async {
+            self.value = newValue
+        }
+    }
+}