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//===----------------------------------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
// dispatch/queue.h
import CDispatch
import _SwiftDispatchOverlayShims
public final class DispatchSpecificKey<T> {
public init() {}
}
internal class _DispatchSpecificValue<T> {
internal let value: T
internal init(value: T) { self.value = value }
}
extension DispatchQueue {
public struct Attributes : OptionSet {
public let rawValue: UInt64
public init(rawValue: UInt64) { self.rawValue = rawValue }
public static let concurrent = Attributes(rawValue: 1<<1)
@available(macOS 10.12, iOS 10.0, tvOS 10.0, watchOS 3.0, *)
public static let initiallyInactive = Attributes(rawValue: 1<<2)
fileprivate func _attr() -> dispatch_queue_attr_t? {
var attr: dispatch_queue_attr_t? = nil
if self.contains(.concurrent) {
attr = _swift_dispatch_queue_concurrent()
}
if #available(macOS 10.12, iOS 10.0, tvOS 10.0, watchOS 3.0, *) {
if self.contains(.initiallyInactive) {
attr = CDispatch.dispatch_queue_attr_make_initially_inactive(attr)
}
}
return attr
}
}
public enum GlobalQueuePriority {
@available(macOS, deprecated: 10.10, message: "Use qos attributes instead")
@available(iOS, deprecated: 8.0, message: "Use qos attributes instead")
@available(tvOS, deprecated, message: "Use qos attributes instead")
@available(watchOS, deprecated, message: "Use qos attributes instead")
case high
@available(macOS, deprecated: 10.10, message: "Use qos attributes instead")
@available(iOS, deprecated: 8.0, message: "Use qos attributes instead")
@available(tvOS, deprecated, message: "Use qos attributes instead")
@available(watchOS, deprecated, message: "Use qos attributes instead")
case `default`
@available(macOS, deprecated: 10.10, message: "Use qos attributes instead")
@available(iOS, deprecated: 8.0, message: "Use qos attributes instead")
@available(tvOS, deprecated, message: "Use qos attributes instead")
@available(watchOS, deprecated, message: "Use qos attributes instead")
case low
@available(macOS, deprecated: 10.10, message: "Use qos attributes instead")
@available(iOS, deprecated: 8.0, message: "Use qos attributes instead")
@available(tvOS, deprecated, message: "Use qos attributes instead")
@available(watchOS, deprecated, message: "Use qos attributes instead")
case background
internal var _translatedValue: Int {
switch self {
case .high: return 2 // DISPATCH_QUEUE_PRIORITY_HIGH
case .default: return 0 // DISPATCH_QUEUE_PRIORITY_DEFAULT
case .low: return -2 // DISPATCH_QUEUE_PRIORITY_LOW
case .background: return Int(Int16.min) // DISPATCH_QUEUE_PRIORITY_BACKGROUND
}
}
}
public enum AutoreleaseFrequency {
case inherit
@available(macOS 10.12, iOS 10.0, tvOS 10.0, watchOS 3.0, *)
case workItem
@available(macOS 10.12, iOS 10.0, tvOS 10.0, watchOS 3.0, *)
case never
internal func _attr(attr: dispatch_queue_attr_t?) -> dispatch_queue_attr_t? {
if #available(macOS 10.12, iOS 10.0, tvOS 10.0, watchOS 3.0, *) {
switch self {
case .inherit:
// DISPATCH_AUTORELEASE_FREQUENCY_INHERIT
return CDispatch.dispatch_queue_attr_make_with_autorelease_frequency(attr, dispatch_autorelease_frequency_t(0))
case .workItem:
// DISPATCH_AUTORELEASE_FREQUENCY_WORK_ITEM
return CDispatch.dispatch_queue_attr_make_with_autorelease_frequency(attr, dispatch_autorelease_frequency_t(1))
case .never:
// DISPATCH_AUTORELEASE_FREQUENCY_NEVER
return CDispatch.dispatch_queue_attr_make_with_autorelease_frequency(attr, dispatch_autorelease_frequency_t(2))
}
} else {
return attr
}
}
}
public class func concurrentPerform(iterations: Int, execute work: (Int) -> Void) {
_swift_dispatch_apply_current(iterations, work)
}
public class var main: DispatchQueue {
return DispatchQueue(queue: _swift_dispatch_get_main_queue())
}
@available(macOS, deprecated: 10.10, message: "")
@available(iOS, deprecated: 8.0, message: "")
@available(tvOS, deprecated, message: "")
@available(watchOS, deprecated, message: "")
public class func global(priority: GlobalQueuePriority) -> DispatchQueue {
return DispatchQueue(queue: CDispatch.dispatch_get_global_queue(Int(priority._translatedValue), 0))
}
@available(macOS 10.10, iOS 8.0, *)
public class func global(qos: DispatchQoS.QoSClass = .default) -> DispatchQueue {
return DispatchQueue(queue: CDispatch.dispatch_get_global_queue(Int(qos.rawValue.rawValue), 0))
}
public class func getSpecific<T>(key: DispatchSpecificKey<T>) -> T? {
let k = Unmanaged.passUnretained(key).toOpaque()
if let p = CDispatch.dispatch_get_specific(k) {
let v = Unmanaged<_DispatchSpecificValue<T>>
.fromOpaque(p)
.takeUnretainedValue()
return v.value
}
return nil
}
public convenience init(
label: String,
qos: DispatchQoS = .unspecified,
attributes: Attributes = [],
autoreleaseFrequency: AutoreleaseFrequency = .inherit,
target: DispatchQueue? = nil)
{
var attr = attributes._attr()
if autoreleaseFrequency != .inherit {
attr = autoreleaseFrequency._attr(attr: attr)
}
if #available(macOS 10.10, iOS 8.0, *), qos != .unspecified {
attr = CDispatch.dispatch_queue_attr_make_with_qos_class(attr, qos.qosClass.rawValue.rawValue, Int32(qos.relativePriority))
}
if #available(macOS 10.12, iOS 10.0, tvOS 10.0, watchOS 3.0, *) {
self.init(__label: label, attr: attr, queue: target)
} else {
self.init(__label: label, attr: attr)
if let tq = target { self.setTarget(queue: tq) }
}
}
public var label: String {
return String(validatingUTF8: dispatch_queue_get_label(self.__wrapped))!
}
///
/// Submits a block for synchronous execution on this queue.
///
/// Submits a work item to a dispatch queue like `async(execute:)`, however
/// `sync(execute:)` will not return until the work item has finished.
///
/// Work items submitted to a queue with `sync(execute:)` do not observe certain
/// queue attributes of that queue when invoked (such as autorelease frequency
/// and QoS class).
///
/// Calls to `sync(execute:)` targeting the current queue will result
/// in deadlock. Use of `sync(execute:)` is also subject to the same
/// multi-party deadlock problems that may result from the use of a mutex.
/// Use of `async(execute:)` is preferred.
///
/// As an optimization, `sync(execute:)` invokes the work item on the thread which
/// submitted it, except when the queue is the main queue or
/// a queue targetting it.
///
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `async(execute:)`
///
@available(macOS 10.10, iOS 8.0, *)
public func sync(execute workItem: DispatchWorkItem) {
CDispatch.dispatch_sync(self.__wrapped, workItem._block)
}
///
/// Submits a work item for asynchronous execution on a dispatch queue.
///
/// `async(execute:)` is the fundamental mechanism for submitting
/// work items to a dispatch queue.
///
/// Calls to `async(execute:)` always return immediately after the work item has
/// been submitted, and never wait for the work item to be invoked.
///
/// The target queue determines whether the work item will be invoked serially or
/// concurrently with respect to other work items submitted to that same queue.
/// Serial queues are processed concurrently with respect to each other.
///
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `sync(execute:)`
///
@available(macOS 10.10, iOS 8.0, *)
public func async(execute workItem: DispatchWorkItem) {
CDispatch.dispatch_async(self.__wrapped, workItem._block)
}
///
/// Submits a work item to a dispatch queue and associates it with the given
/// dispatch group. The dispatch group may be used to wait for the completion
/// of the work items it references.
///
/// - parameter group: the dispatch group to associate with the submitted block.
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `sync(execute:)`
///
@available(macOS 10.10, iOS 8.0, *)
public func async(group: DispatchGroup, execute workItem: DispatchWorkItem) {
CDispatch.dispatch_group_async(group.__wrapped, self.__wrapped, workItem._block)
}
///
/// Submits a work item to a dispatch queue and optionally associates it with a
/// dispatch group. The dispatch group may be used to wait for the completion
/// of the work items it references.
///
/// - parameter group: the dispatch group to associate with the submitted
/// work item. If this is `nil`, the work item is not associated with a group.
/// - parameter flags: flags that control the execution environment of the
/// - parameter qos: the QoS at which the work item should be executed.
/// Defaults to `DispatchQoS.unspecified`.
/// - parameter flags: flags that control the execution environment of the
/// work item.
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `sync(execute:)`
/// - SeeAlso: `DispatchQoS`
/// - SeeAlso: `DispatchWorkItemFlags`
///
public func async(
group: DispatchGroup? = nil,
qos: DispatchQoS = .unspecified,
flags: DispatchWorkItemFlags = [],
execute work: @escaping @convention(block) () -> Void)
{
if group == nil && qos == .unspecified {
// Fast-path route for the most common API usage
if flags.isEmpty {
CDispatch.dispatch_async(self.__wrapped, work)
return
} else if flags == .barrier {
CDispatch.dispatch_barrier_async(self.__wrapped, work)
return
}
}
var block: @convention(block) () -> Void = work
if #available(macOS 10.10, iOS 8.0, *), (qos != .unspecified || !flags.isEmpty) {
let workItem = DispatchWorkItem(qos: qos, flags: flags, block: work)
block = workItem._block
}
if let g = group {
CDispatch.dispatch_group_async(g.__wrapped, self.__wrapped, block)
} else {
CDispatch.dispatch_async(self.__wrapped, block)
}
}
private func _syncBarrier(block: () -> ()) {
CDispatch.dispatch_barrier_sync(self.__wrapped, block)
}
private func _syncHelper<T>(
fn: (() -> ()) -> (),
execute work: () throws -> T,
rescue: ((Swift.Error) throws -> (T))) rethrows -> T
{
var result: T?
var error: Swift.Error?
withoutActuallyEscaping(work) { _work in
fn {
do {
result = try _work()
} catch let e {
error = e
}
}
}
if let e = error {
return try rescue(e)
} else {
return result!
}
}
@available(macOS 10.10, iOS 8.0, *)
private func _syncHelper<T>(
fn: (DispatchWorkItem) -> (),
flags: DispatchWorkItemFlags,
execute work: () throws -> T,
rescue: @escaping ((Swift.Error) throws -> (T))) rethrows -> T
{
var result: T?
var error: Swift.Error?
let workItem = DispatchWorkItem(flags: flags, noescapeBlock: {
do {
result = try work()
} catch let e {
error = e
}
})
fn(workItem)
if let e = error {
return try rescue(e)
} else {
return result!
}
}
///
/// Submits a block for synchronous execution on this queue.
///
/// Submits a work item to a dispatch queue like `sync(execute:)`, and returns
/// the value, of type `T`, returned by that work item.
///
/// - parameter execute: The work item to be invoked on the queue.
/// - returns the value returned by the work item.
/// - SeeAlso: `sync(execute:)`
///
public func sync<T>(execute work: () throws -> T) rethrows -> T {
return try self._syncHelper(fn: sync, execute: work, rescue: { throw $0 })
}
///
/// Submits a block for synchronous execution on this queue.
///
/// Submits a work item to a dispatch queue like `sync(execute:)`, and returns
/// the value, of type `T`, returned by that work item.
///
/// - parameter flags: flags that control the execution environment of the
/// - parameter execute: The work item to be invoked on the queue.
/// - returns the value returned by the work item.
/// - SeeAlso: `sync(execute:)`
/// - SeeAlso: `DispatchWorkItemFlags`
///
public func sync<T>(flags: DispatchWorkItemFlags, execute work: () throws -> T) rethrows -> T {
if flags == .barrier {
return try self._syncHelper(fn: _syncBarrier, execute: work, rescue: { throw $0 })
} else if #available(macOS 10.10, iOS 8.0, *), !flags.isEmpty {
return try self._syncHelper(fn: sync, flags: flags, execute: work, rescue: { throw $0 })
} else {
return try self._syncHelper(fn: sync, execute: work, rescue: { throw $0 })
}
}
///
/// Submits a work item to a dispatch queue for asynchronous execution after
/// a specified time.
///
/// - parameter: deadline the time after which the work item should be executed,
/// given as a `DispatchTime`.
/// - parameter qos: the QoS at which the work item should be executed.
/// Defaults to `DispatchQoS.unspecified`.
/// - parameter flags: flags that control the execution environment of the
/// work item.
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `async(execute:)`
/// - SeeAlso: `asyncAfter(deadline:execute:)`
/// - SeeAlso: `DispatchQoS`
/// - SeeAlso: `DispatchWorkItemFlags`
/// - SeeAlso: `DispatchTime`
///
public func asyncAfter(
deadline: DispatchTime,
qos: DispatchQoS = .unspecified,
flags: DispatchWorkItemFlags = [],
execute work: @escaping @convention(block) () -> Void)
{
if #available(macOS 10.10, iOS 8.0, *), qos != .unspecified || !flags.isEmpty {
let item = DispatchWorkItem(qos: qos, flags: flags, block: work)
CDispatch.dispatch_after(deadline.rawValue, self.__wrapped, item._block)
} else {
CDispatch.dispatch_after(deadline.rawValue, self.__wrapped, work)
}
}
///
/// Submits a work item to a dispatch queue for asynchronous execution after
/// a specified time.
///
/// - parameter: deadline the time after which the work item should be executed,
/// given as a `DispatchWallTime`.
/// - parameter qos: the QoS at which the work item should be executed.
/// Defaults to `DispatchQoS.unspecified`.
/// - parameter flags: flags that control the execution environment of the
/// work item.
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `async(execute:)`
/// - SeeAlso: `asyncAfter(wallDeadline:execute:)`
/// - SeeAlso: `DispatchQoS`
/// - SeeAlso: `DispatchWorkItemFlags`
/// - SeeAlso: `DispatchWallTime`
///
public func asyncAfter(
wallDeadline: DispatchWallTime,
qos: DispatchQoS = .unspecified,
flags: DispatchWorkItemFlags = [],
execute work: @escaping @convention(block) () -> Void)
{
if #available(macOS 10.10, iOS 8.0, *), qos != .unspecified || !flags.isEmpty {
let item = DispatchWorkItem(qos: qos, flags: flags, block: work)
CDispatch.dispatch_after(wallDeadline.rawValue, self.__wrapped, item._block)
} else {
CDispatch.dispatch_after(wallDeadline.rawValue, self.__wrapped, work)
}
}
///
/// Submits a work item to a dispatch queue for asynchronous execution after
/// a specified time.
///
/// - parameter: deadline the time after which the work item should be executed,
/// given as a `DispatchTime`.
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `asyncAfter(deadline:qos:flags:execute:)`
/// - SeeAlso: `DispatchTime`
///
@available(macOS 10.10, iOS 8.0, *)
public func asyncAfter(deadline: DispatchTime, execute: DispatchWorkItem) {
CDispatch.dispatch_after(deadline.rawValue, self.__wrapped, execute._block)
}
///
/// Submits a work item to a dispatch queue for asynchronous execution after
/// a specified time.
///
/// - parameter: deadline the time after which the work item should be executed,
/// given as a `DispatchWallTime`.
/// - parameter execute: The work item to be invoked on the queue.
/// - SeeAlso: `asyncAfter(wallDeadline:qos:flags:execute:)`
/// - SeeAlso: `DispatchTime`
///
@available(macOS 10.10, iOS 8.0, *)
public func asyncAfter(wallDeadline: DispatchWallTime, execute: DispatchWorkItem) {
CDispatch.dispatch_after(wallDeadline.rawValue, self.__wrapped, execute._block)
}
@available(macOS 10.10, iOS 8.0, *)
public var qos: DispatchQoS {
var relPri: Int32 = 0
let cls = DispatchQoS.QoSClass(rawValue: _OSQoSClass(qosClass: dispatch_queue_get_qos_class(self.__wrapped, &relPri))!)!
return DispatchQoS(qosClass: cls, relativePriority: Int(relPri))
}
public func getSpecific<T>(key: DispatchSpecificKey<T>) -> T? {
let k = Unmanaged.passUnretained(key).toOpaque()
if let p = dispatch_queue_get_specific(self.__wrapped, k) {
let v = Unmanaged<_DispatchSpecificValue<T>>
.fromOpaque(p)
.takeUnretainedValue()
return v.value
}
return nil
}
public func setSpecific<T>(key: DispatchSpecificKey<T>, value: T?) {
let k = Unmanaged.passUnretained(key).toOpaque()
let v = value.map { _DispatchSpecificValue(value: $0) }
let p = v.map { Unmanaged.passRetained($0).toOpaque() }
dispatch_queue_set_specific(self.__wrapped, k, p, _destructDispatchSpecificValue)
}
#if os(Android)
public static func setThreadDetachCallback(_ cb: @escaping @convention(c) () -> Void) {
_dispatch_install_thread_detach_callback(cb)
}
#endif
}
private func _destructDispatchSpecificValue(ptr: UnsafeMutableRawPointer?) {
if let p = ptr {
Unmanaged<AnyObject>.fromOpaque(p).release()
}
}