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dilepingdileping
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Added semaphore
1 parent f2847cf commit 4038741

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3 files changed

+114
-3
lines changed

3 files changed

+114
-3
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‎ExecutionContext.xcodeproj/project.pbxproj‎

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@@ -29,6 +29,10 @@
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65E646DE1C7994A00036D028 /* CustomExecutionContext.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646DC1C79949C0036D028 /* CustomExecutionContext.swift */; };
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65E646DF1C7994A10036D028 /* CustomExecutionContext.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646DC1C79949C0036D028 /* CustomExecutionContext.swift */; };
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65E646E01C7994A20036D028 /* CustomExecutionContext.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646DC1C79949C0036D028 /* CustomExecutionContext.swift */; };
32+
65E646F21C79E0590036D028 /* Semaphore.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646F11C79E0580036D028 /* Semaphore.swift */; };
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65E646F31C79E0590036D028 /* Semaphore.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646F11C79E0580036D028 /* Semaphore.swift */; };
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65E646F41C79E0590036D028 /* Semaphore.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646F11C79E0580036D028 /* Semaphore.swift */; };
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65E646F51C79E0590036D028 /* Semaphore.swift in Sources */ = {isa = PBXBuildFile; fileRef = 65E646F11C79E0580036D028 /* Semaphore.swift */; };
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65FB86901C78A8330005CD1B /* Result.framework in Copy Frameworks */ = {isa = PBXBuildFile; fileRef = 659E80E61C78A70700DE85B1 /* Result.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
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65FB86921C78A8D30005CD1B /* Result.framework in Copy Frameworks */ = {isa = PBXBuildFile; fileRef = 659E80E31C78A70700DE85B1 /* Result.framework */; settings = {ATTRIBUTES = (CodeSignOnCopy, RemoveHeadersOnCopy, ); }; };
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65FB86A21C78AA400005CD1B /* ExecutionContext.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 65FB86981C78AA400005CD1B /* ExecutionContext.framework */; };
@@ -141,6 +145,7 @@
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659E80F01C78A70700DE85B1 /* Result.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; path = Result.framework; sourceTree = "<group>"; };
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659E80F11C78A70700DE85B1 /* Result.framework.dSYM */ = {isa = PBXFileReference; lastKnownFileType = wrapper.dsym; path = Result.framework.dSYM; sourceTree = "<group>"; };
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65E646DC1C79949C0036D028 /* CustomExecutionContext.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = CustomExecutionContext.swift; sourceTree = "<group>"; };
148+
65E646F11C79E0580036D028 /* Semaphore.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = Semaphore.swift; sourceTree = "<group>"; };
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65FB86981C78AA400005CD1B /* ExecutionContext.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = ExecutionContext.framework; sourceTree = BUILT_PRODUCTS_DIR; };
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65FB86A11C78AA400005CD1B /* ExecutionContextTests-tvOS.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = "ExecutionContextTests-tvOS.xctest"; sourceTree = BUILT_PRODUCTS_DIR; };
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65FB86BE1C78AC260005CD1B /* ExecutionContext.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = ExecutionContext.framework; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -240,6 +245,7 @@
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659E809B1C77457E00DE85B1 /* ImmediateExecutionContext.swift */,
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65E646DC1C79949C0036D028 /* CustomExecutionContext.swift */,
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659E809D1C77457E00DE85B1 /* Result+Some.swift */,
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65E646F11C79E0580036D028 /* Semaphore.swift */,
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659E80831C77450200DE85B1 /* Info.plist */,
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);
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path = ExecutionContext;
@@ -596,6 +602,7 @@
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659E80A31C77457E00DE85B1 /* Result+Some.swift in Sources */,
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659E80A11C77457E00DE85B1 /* ImmediateExecutionContext.swift in Sources */,
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659E809E1C77457E00DE85B1 /* DefaultExecutionContext.swift in Sources */,
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65E646F21C79E0590036D028 /* Semaphore.swift in Sources */,
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659E80A21C77457E00DE85B1 /* PThreadExecutionContext.swift in Sources */,
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);
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runOnlyForDeploymentPostprocessing = 0;
@@ -618,6 +625,7 @@
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659E80DC1C78A4BC00DE85B1 /* Result+Some.swift in Sources */,
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659E80DB1C78A4B800DE85B1 /* ImmediateExecutionContext.swift in Sources */,
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659E80D71C78A4AB00DE85B1 /* ExecutionContext.swift in Sources */,
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65E646F31C79E0590036D028 /* Semaphore.swift in Sources */,
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659E80D91C78A4B200DE85B1 /* DispatchExecutionContext.swift in Sources */,
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);
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runOnlyForDeploymentPostprocessing = 0;
@@ -640,6 +648,7 @@
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65FB86B41C78AAE50005CD1B /* Result+Some.swift in Sources */,
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65FB86B31C78AAE50005CD1B /* ImmediateExecutionContext.swift in Sources */,
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65FB86AF1C78AADB0005CD1B /* ExecutionContext.swift in Sources */,
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65E646F41C79E0590036D028 /* Semaphore.swift in Sources */,
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65FB86B11C78AAE50005CD1B /* DispatchExecutionContext.swift in Sources */,
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);
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runOnlyForDeploymentPostprocessing = 0;
@@ -662,6 +671,7 @@
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65FB86CB1C78AC8B0005CD1B /* Result+Some.swift in Sources */,
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65FB86CA1C78AC8B0005CD1B /* ImmediateExecutionContext.swift in Sources */,
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65FB86C61C78AC8B0005CD1B /* ExecutionContext.swift in Sources */,
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65E646F51C79E0590036D028 /* Semaphore.swift in Sources */,
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65FB86C81C78AC8B0005CD1B /* DispatchExecutionContext.swift in Sources */,
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);
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runOnlyForDeploymentPostprocessing = 0;

‎ExecutionContext/Semaphore.swift‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,87 @@
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//===--- Semaphore.swift ------------------------------------------------------===//
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//Copyright (c) 2016 Daniel Leping (dileping)
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//
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//Licensed under the Apache License, Version 2.0 (the "License");
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//you may not use this file except in compliance with the License.
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//You may obtain a copy of the License at
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//
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//http://www.apache.org/licenses/LICENSE-2.0
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//
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//Unless required by applicable law or agreed to in writing, software
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//distributed under the License is distributed on an "AS IS" BASIS,
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//WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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//See the License for the specific language governing permissions and
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//limitations under the License.
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//===----------------------------------------------------------------------===//
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import Foundation
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private extension NSCondition {
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func waitWithConditionalEnd(date:NSDate?) -> Bool {
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guard let date = date else {
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self.wait()
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return true
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}
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return self.waitUntilDate(date)
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}
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}
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/// A wrapper around NSCondition
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public class Semaphore {
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/// The underlying NSCondition
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private(set) public var underlyingSemaphore: NSCondition
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private(set) public var value: Int
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/// Creates a new semaphore with the given initial value
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/// See NSCondition and https://developer.apple.com/library/prerelease/mac/documentation/Cocoa/Conceptual/Multithreading/ThreadSafety/ThreadSafety.html#//apple_ref/doc/uid/10000057i-CH8-SW13
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public init(value: Int) {
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self.underlyingSemaphore = NSCondition()
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self.value = value
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}
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/// Creates a new semaphore with initial value 1
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/// This kind of semaphores is useful to protect a critical section
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public convenience init() {
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self.init(value: 1)
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}
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/// returns true on success (false if timeout expired)
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/// if nil is passed - waits forever
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public func wait(until:NSDate? = nil) -> Bool {
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underlyingSemaphore.lock()
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defer {
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value -= 1
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underlyingSemaphore.unlock()
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}
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var signaled:Bool = true
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while value <= 0 {
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signaled = underlyingSemaphore.waitWithConditionalEnd(until)
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if !signaled {
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break
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}
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}
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return signaled
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}
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/// Performs the wait operation on this semaphore until the timeout
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/// Returns true if the semaphore was signalled before the timeout occurred
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/// or false if the timeout occurred.
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public func wait(timeout: Double?) -> Bool {
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let until = timeout.flatMap {$0 <= 0 ? nil : $0}.map{NSDate(timeIntervalSinceNow: $0)}
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return wait(until)
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}
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/// Performs the signal operation on this semaphore
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public func signal() -> Int {
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underlyingSemaphore.lock()
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defer {
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underlyingSemaphore.unlock()
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}
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value += 1
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underlyingSemaphore.signal()
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return value
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}
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}

‎Tests/ExecutionContext/ExecutionContextTests.swift‎

Lines changed: 17 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -37,7 +37,7 @@ class ExecutionContextTests: XCTestCase {
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let expectation = self.expectationWithDescription("OK ASYNC")
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context.async {
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sleep(1)
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sleep(1.0)
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expectation.fulfill()
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}
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@@ -61,11 +61,11 @@ class ExecutionContextTests: XCTestCase {
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ok = false
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}
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sleep(2)
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sleep(2.0)
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XCTAssert(ok)
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sleep(2)
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sleep(2.0)
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XCTAssertFalse(ok)
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}
@@ -134,6 +134,20 @@ class ExecutionContextTests: XCTestCase {
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afterTest(context)
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//afterTestAdvanced - no it will not work here
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}
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func testSemaphore() {
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let sema = Semaphore()
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var n = 0
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for _ in [0...100] {
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global.execute {
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sema.wait()
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n += 1
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sleep(0.1)
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n -= 1
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sema.signal()
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}
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}
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}
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}
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#if os(Linux)

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