Atomic.swift (2008B)
1 // MIT License 2 // Copyright 2023 Marc Stibane 3 // 4 // Permission is hereby granted, free of charge, to any person obtaining a copy of this software 5 // and associated documentation files (the "Software"), to deal in the Software without restriction, 6 // including without limitation the rights to use, copy, modify, merge, publish, distribute, 7 // sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is 8 // furnished to do so, subject to the following conditions: 9 // 10 // The above copyright notice and this permission notice shall be included in all copies or 11 // substantial portions of the Software. 12 // 13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING 14 // BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 16 // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 17 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 18 // 19 import Foundation 20 21 @propertyWrapper 22 class Atomic<Value> where Value: BinaryInteger { 23 24 private let lock: NSLock 25 private var value: Value 26 27 init(default: Value) { 28 self.lock = NSLock() 29 self.value = `default` 30 } 31 32 var wrappedValue: Value { 33 get { 34 lock.lock() 35 defer { lock.unlock() } 36 return value 37 } 38 set { 39 lock.lock() 40 value = newValue 41 lock.unlock() 42 } 43 } 44 45 var projectedValue: Atomic<Value> { self } 46 47 @discardableResult 48 func atomicIncrement() -> Value { 49 lock.lock() 50 defer { lock.unlock() } 51 self.value += 1 52 return value 53 } 54 55 @discardableResult 56 func atomicAdd(_ value: Value) -> Value { 57 lock.lock() 58 defer { lock.unlock() } 59 self.value += value 60 return value 61 } 62 }