source-code

source-code/ALTs/AltStore/Operations/FindServerOperation.swift

@@ -0,0 +1,115 @@
+//
+//  FindServerOperation.swift
+//  AltStore
+//
+//  Created by Riley Testut on 9/8/19.
+//  Copyright © 2019 Riley Testut. All rights reserved.
+//
+
+import Foundation
+import AltKit
+import Roxas
+
+private let ReceivedServerConnectionResponse: @convention(c) (CFNotificationCenter?, UnsafeMutableRawPointer?, CFNotificationName?, UnsafeRawPointer?, CFDictionary?) -> Void =
+{ (center, observer, name, object, userInfo) in
+    guard let name = name, let observer = observer else { return }
+    
+    let operation = unsafeBitCast(observer, to: FindServerOperation.self)
+    operation.handle(name)
+}
+
+@objc(FindServerOperation)
+class FindServerOperation: ResultOperation<Server>
+{
+    let context: OperationContext
+    
+    private var isWiredServerConnectionAvailable = false
+    private var isLocalServerConnectionAvailable = false
+    
+    init(context: OperationContext = OperationContext())
+    {
+        self.context = context
+    }
+    
+    override func main()
+    {
+        super.main()
+        
+        if let error = self.context.error
+        {
+            self.finish(.failure(error))
+            return
+        }
+        
+        if let server = self.context.server
+        {
+            self.finish(.success(server))
+            return
+        }
+        
+        let notificationCenter = CFNotificationCenterGetDarwinNotifyCenter()
+        let observer = Unmanaged.passUnretained(self).toOpaque()
+        
+        // Prepare observers to receive callback from wired connection or background daemon (if available).
+        CFNotificationCenterAddObserver(notificationCenter, observer, ReceivedServerConnectionResponse, CFNotificationName.wiredServerConnectionAvailableResponse.rawValue, nil, .deliverImmediately)
+        CFNotificationCenterAddObserver(notificationCenter, observer, ReceivedServerConnectionResponse, CFNotificationName.localServerConnectionAvailableResponse.rawValue, nil, .deliverImmediately)
+        
+        // Post notifications.
+        CFNotificationCenterPostNotification(notificationCenter, .wiredServerConnectionAvailableRequest, nil, nil, true)
+        CFNotificationCenterPostNotification(notificationCenter, .localServerConnectionAvailableRequest, nil, nil, true)
+        
+        // Wait for either callback or timeout.
+        DispatchQueue.global().asyncAfter(deadline: .now() + 1.0) {
+            if self.isLocalServerConnectionAvailable
+            {
+                // Prefer background daemon, if it exists and is running.
+                let server = Server(connectionType: .local)
+                self.finish(.success(server))
+            }
+            else if self.isWiredServerConnectionAvailable
+            {
+                let server = Server(connectionType: .wired)
+                self.finish(.success(server))
+            }
+            else if let server = ServerManager.shared.discoveredServers.first(where: { $0.isPreferred })
+            {
+                // Preferred server.
+                self.finish(.success(server))
+            }
+            else if let server = ServerManager.shared.discoveredServers.first
+            {
+                // Any available server.
+                self.finish(.success(server))
+            }
+            else
+            {
+                // No servers.
+                self.finish(.failure(ConnectionError.serverNotFound))
+            }
+        }
+    }
+    
+    override func finish(_ result: Result<Server, Error>)
+    {
+        super.finish(result)
+        
+        let notificationCenter = CFNotificationCenterGetDarwinNotifyCenter()
+        let observer = Unmanaged.passUnretained(self).toOpaque()
+        
+        CFNotificationCenterRemoveObserver(notificationCenter, observer, .wiredServerConnectionAvailableResponse, nil)
+        CFNotificationCenterRemoveObserver(notificationCenter, observer, .localServerConnectionAvailableResponse, nil)
+    }
+}
+
+fileprivate extension FindServerOperation
+{
+    func handle(_ notification: CFNotificationName)
+    {
+        switch notification
+        {
+        case .wiredServerConnectionAvailableResponse: self.isWiredServerConnectionAvailable = true
+        case .localServerConnectionAvailableResponse: self.isLocalServerConnectionAvailable = true
+        default: break
+        }
+    }
+}