VPNC control and logging (#748)

VPNC control and logging

client/platforms/ios/VPNCController.swift

@@ -0,0 +1,50 @@
+import Foundation
+import NetworkExtension
+
+public func removeVPNC(_ vpncName: std.string) {
+  let vpncName = String(describing: vpncName)
+
+  Task {
+    await getManagers()?.first { manager in
+      if let name = manager.localizedDescription, name == vpncName {
+        Task {
+          await remove(manager)
+        }
+
+        return true
+      } else {
+        return false
+      }
+    }
+  }
+}
+
+public func clearSettings() {
+  Task {
+    await getManagers()?.forEach { manager in
+      Task {
+        await remove(manager)
+      }
+    }
+  }
+}
+
+func getManagers() async -> [NETunnelProviderManager]? {
+  do {
+    return try await NETunnelProviderManager.loadAllFromPreferences()
+  } catch {
+    log(.error, title: "VPNC: ", message: "loadAllFromPreferences error: \(error.localizedDescription)")
+    return nil
+  }
+}
+
+func remove(_ manager: NETunnelProviderManager) async {
+  let vpncName = manager.localizedDescription ?? "Unknown"
+  do {
+    try await manager.removeFromPreferences()
+    try await manager.loadFromPreferences()
+    log(.info, title: "VPNC: ", message: "Remove \(vpncName)")
+  } catch {
+    log(.error, title: "VPNC: ", message: "Failed to remove \(vpncName) (\(error.localizedDescription))")
+  }
+}