Implemented recursive lock using pthread mutex

Dip/DipLinuxTests/Package.swift

@@ -0,0 +1,10 @@
+import PackageDescription
+
+let package = Package(
+        name: "DipLinuxTests",
+        targets: [],
+        dependencies: [
+                .Package(url: "https://github.com/AliSoftware/Dip", majorVersion: 4, minor: 2),
+        ]
+)
+

Dip/DipLinuxTests/Sources/main.swift

@@ -0,0 +1,156 @@
+import Glibc
+import XCTest
+import Dip
+
+
+private protocol Service: class {
+  var client: Client? { get set }
+}
+
+private protocol Client: class {
+  var service: Service { get }
+}
+
+private class ClientImp: Client, Equatable {
+  var service: Service
+  init(service: Service) {
+    self.service = service
+  }
+}
+
+private func ==<T: ClientImp>(lhs: T, rhs: T) -> Bool {
+  return lhs === rhs
+}
+
+private class ServiceImp: Service, Hashable {
+  weak var client: Client?
+  init() {}
+
+  var hashValue: Int {
+    return unsafeAddressOf(self).hashValue
+  }
+}
+
+private func ==<T: ServiceImp>(lhs: T, rhs: T) -> Bool {
+  return lhs === rhs
+}
+
+
+typealias TMain = @convention(c) (UnsafeMutablePointer<Void>) -> UnsafeMutablePointer<Void>
+
+func dispatch_async(block: TMain) {
+  var pid: pthread_t = 0
+  pthread_create(&pid, nil, block, nil)
+}
+
+func dispatch_sync(block: TMain) -> UnsafeMutablePointer<Void> {
+  var pid: pthread_t = 0
+  var result: UnsafeMutablePointer<Void> = nil
+  pthread_create(&pid, nil, block, nil)
+  pthread_join(pid, &result)
+  return result
+}
+
+private var resolvedServices = Set<ServiceImp>()
+private var resolvedClients = Array<ClientImp>()
+
+private var lock: pthread_spinlock_t = 0
+pthread_spin_init(&lock, 0)
+
+private var container: DependencyContainer!
+
+class ThreadSafetyTests: XCTestCase {
+
+  var allTests: [(String, () throws -> Void)] {
+    return [
+      ("testSingletonThreadSafety", testSingletonThreadSafety),
+      ("testFactoryThreadSafety", testFactoryThreadSafety),
+      ("testCircularReferenceThreadSafety", testCircularReferenceThreadSafety)
+    ]
+  }
+
+  func setUp() {
+    container = DependencyContainer()
+  }
+
+  func tearDown() {
+  }
+
+  func testSingletonThreadSafety() {
+    container.register(.Singleton) { ServiceImp() as Service }
+
+    for _ in 0..<100 {
+      dispatch_async { _ in
+        let service = try! container.resolve() as Service
+        pthread_spin_lock(&lock)
+        resolvedServices.insert(service as! ServiceImp)
+        pthread_spin_unlock(&lock)
+        return nil
+      }
+    }
+
+    sleep(1)
+    XCTAssertEqual(resolvedServices.count, 1, "Should create only one instance")
+    resolvedServices.removeAll()
+  }
+
+
+  func testFactoryThreadSafety() {
+    container.register { ServiceImp() as Service }
+
+    for _ in 0..<100 {
+      dispatch_async { _ in
+        let service = try! container.resolve() as Service
+        pthread_spin_lock(&lock)
+        resolvedServices.insert(service as! ServiceImp)
+        pthread_spin_unlock(&lock)
+        return nil
+      }
+    }
+
+    sleep(1)
+    XCTAssertEqual(resolvedServices.count, 100, "All instances should be different")
+    resolvedServices.removeAll()
+  }
+
+
+  func testCircularReferenceThreadSafety() {
+    container.register(.ObjectGraph) { ClientImp(service: try container.resolve()) as Client }
+
+    let resolveClient: TMain = { _ in
+      let resolved = try! container.resolve() as Client
+      return UnsafeMutablePointer(Unmanaged.passUnretained(resolved as! ClientImp).toOpaque())
+    }
+    container.register(.ObjectGraph) { ServiceImp() as Service }
+      .resolveDependencies { container, service in
+        var clientPointer: UnsafeMutablePointer<Void> = nil
+        clientPointer = dispatch_sync(resolveClient)
+        let client = Unmanaged<ClientImp>.fromOpaque(COpaquePointer(clientPointer)).takeUnretainedValue()
+        service.client = client
+    }
+
+    for _ in 0..<100 {
+      dispatch_async { _ in
+        let client = try! container.resolve() as Client
+        pthread_spin_lock(&lock)
+        resolvedClients.append(client as! ClientImp)
+        pthread_spin_unlock(&lock)
+        return nil
+      }
+    }
+
+    sleep(2)
+
+    XCTAssertEqual(resolvedClients.count, 100, "Instances should be not reused in different object graphs")
+    for client in resolvedClients {
+      let service = client.service as! ServiceImp
+      let serviceClient = service.client as! ClientImp
+      XCTAssertEqual(serviceClient, client, "Instances should be reused when resolving single object graph")
+    }
+
+    resolvedClients.removeAll()
+  }
+
+}
+
+XCTMain([ThreadSafetyTests()])

Sources/Dip.swift

@@ -22,8 +22,6 @@
 // THE SOFTWARE.
 //
 
-import Foundation
-
 // MARK: - DependencyContainer
 
 /**
@@ -43,7 +41,7 @@ public final class DependencyContainer {
 
   var definitions = [DefinitionKey : Definition]()
   let resolvedInstances = ResolvedInstances()
-  let lock = NSRecursiveLock()
+  let lock = RecursiveLock()
 
   /**
    Designated initializer for a DependencyContainer

Sources/Utils.swift

@@ -22,8 +22,6 @@
 // THE SOFTWARE.
 //
 
-import Foundation
-
 extension Dictionary {
   subscript(key: Key?) -> Value? {
     get {
@@ -42,3 +40,45 @@ extension Optional {
     return self.map { "\($0)" } ?? "nil"
   }
 }
+
+#if os(Linux)
+  import Glibc
+  class RecursiveLock {
+    private var _lock = _initializeRecursiveMutex()
+
+    func lock() {
+      _lock.lock()
+    }
+
+    func unlock() {
+      _lock.unlock()
+    }
+
+    deinit {
+      pthread_mutex_destroy(&_lock)
+    }
+
+  }
+
+  private func _initializeRecursiveMutex() -> pthread_mutex_t {
+    var mutex: pthread_mutex_t = pthread_mutex_t()
+    var mta: pthread_mutexattr_t = pthread_mutexattr_t()
+    pthread_mutexattr_init(&mta)
+    pthread_mutexattr_settype(&mta, Int32(PTHREAD_MUTEX_RECURSIVE))
+    pthread_mutex_init(&mutex, &mta)
+    return mutex
+  }
+
+  extension pthread_mutex_t {
+    mutating func lock() {
+      pthread_mutex_trylock(&self)
+    }
+    mutating func unlock() {
+      pthread_mutex_unlock(&self)
+    }
+  }
+
+#else
+  import Foundation
+  typealias RecursiveLock = NSRecursiveLock
+#endif