43 lines
1.4 KiB
Swift
43 lines
1.4 KiB
Swift
//===----------------------------------------------------------------------===//
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//
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// This source file is part of the SwiftNIO open source project
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//
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// Copyright (c) 2022 Apple Inc. and the SwiftNIO project authors
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// Licensed under Apache License v2.0
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//
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// See LICENSE.txt for license information
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// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
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//
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// SPDX-License-Identifier: Apache-2.0
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//
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//===----------------------------------------------------------------------===//
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/// Provides locked access to `Value`.
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///
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/// - note: ``NIOLockedValueBox`` has reference semantics and holds the `Value`
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/// alongside a lock behind a reference.
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///
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/// This is no different than creating a ``Lock`` and protecting all
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/// accesses to a value using the lock. But it's easy to forget to actually
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/// acquire/release the lock in the correct place. ``NIOLockedValueBox`` makes
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/// that much easier.
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public struct NIOLockedValueBox<Value> {
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@usableFromInline
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internal let _storage: LockStorage<Value>
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/// Initialize the `Value`.
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@inlinable
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public init(_ value: Value) {
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self._storage = .create(value: value)
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}
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/// Access the `Value`, allowing mutation of it.
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@inlinable
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public func withLockedValue<T>(_ mutate: (inout Value) throws -> T) rethrows -> T {
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return try self._storage.withLockedValue(mutate)
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}
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}
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extension NIOLockedValueBox: Sendable where Value: Sendable {}
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