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@_implementationOnly import os | |
// Backports the Swift interface around os_unfair_lock_t available in recent Darwin platforms | |
// https://github.com/swhitty/AllocatedLock | |
// | |
@available(iOS, deprecated: 16.0, message: "use OSAllocatedUnfairLock directly") | |
@available(tvOS, deprecated: 16.0, message: "use OSAllocatedUnfairLock directly") | |
@available(watchOS, deprecated: 9, message: "use OSAllocatedUnfairLock directly") | |
@available(macOS, deprecated: 13.0, message: "use OSAllocatedUnfairLock directly") | |
public struct AllocatedLock<State>: @unchecked Sendable { | |
@usableFromInline | |
let storage: Storage | |
public init(initialState: State) { | |
self.storage = Storage(initialState: initialState) | |
} | |
@inlinable | |
public func withLock<R>(_ body: @Sendable (inout State) throws -> R) rethrows -> R where R: Sendable { | |
storage.lock() | |
defer { storage.unlock() } | |
return try body(&storage.state) | |
} | |
} | |
public extension AllocatedLock where State == Void { | |
init() { | |
self.storage = Storage(initialState: ()) | |
} | |
@inlinable @available(*, noasync) | |
func lock() { | |
storage.lock() | |
} | |
@inlinable @available(*, noasync) | |
func unlock() { | |
storage.unlock() | |
} | |
@inlinable | |
func withLock<R>(_ body: @Sendable () throws -> R) rethrows -> R where R: Sendable { | |
storage.lock() | |
defer { storage.unlock() } | |
return try body() | |
} | |
} | |
@_implementationOnly import os | |
extension AllocatedLock { | |
@usableFromInline | |
final class Storage { | |
private let _lock: os_unfair_lock_t | |
@usableFromInline | |
var state: State | |
init(initialState: State) { | |
self._lock = .allocate(capacity: 1) | |
self._lock.initialize(to: os_unfair_lock()) | |
self.state = initialState | |
} | |
@usableFromInline | |
func lock() { | |
os_unfair_lock_lock(_lock) | |
} | |
@usableFromInline | |
func unlock() { | |
os_unfair_lock_unlock(_lock) | |
} | |
deinit { | |
self._lock.deinitialize(count: 1) | |
self._lock.deallocate() | |
} | |
} | |
} |
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