WireGuard add extra source files

Signed-off-by: Joseph Mattello <mail@joemattiello.com>

WireguardNetworkExtension/FileManager+Extension.swift

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: MIT
+// Copyright © 2018-2021 WireGuard LLC. All Rights Reserved.
+
+import Foundation
+import os.log
+
+extension FileManager {
+    static var appGroupId: String? {
+        #if os(iOS)
+        let appGroupIdInfoDictionaryKey = "com.wireguard.ios.app_group_id"
+        #elseif os(macOS)
+        let appGroupIdInfoDictionaryKey = "com.wireguard.macos.app_group_id"
+        #else
+        #error("Unimplemented")
+        #endif
+        return Bundle.main.object(forInfoDictionaryKey: appGroupIdInfoDictionaryKey) as? String
+    }
+    private static var sharedFolderURL: URL? {
+        guard let appGroupId = FileManager.appGroupId else {
+            os_log("Cannot obtain app group ID from bundle", log: OSLog.default, type: .error)
+            return nil
+        }
+        guard let sharedFolderURL = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: appGroupId) else {
+            wg_log(.error, message: "Cannot obtain shared folder URL")
+            return nil
+        }
+        return sharedFolderURL
+    }
+
+    static var logFileURL: URL? {
+        return sharedFolderURL?.appendingPathComponent("tunnel-log.bin")
+    }
+
+    static var networkExtensionLastErrorFileURL: URL? {
+        return sharedFolderURL?.appendingPathComponent("last-error.txt")
+    }
+
+    static var loginHelperTimestampURL: URL? {
+        return sharedFolderURL?.appendingPathComponent("login-helper-timestamp.bin")
+    }
+
+    static func deleteFile(at url: URL) -> Bool {
+        do {
+            try FileManager.default.removeItem(at: url)
+        } catch {
+            return false
+        }
+        return true
+    }
+}