enumerate iphone interfaces in swift and objective-c

network_interface.swift

private struct InterfaceNames {
    static let wifi = ["en0"]
    static let wired = ["en2", "en3", "en4"]
    static let cellular = ["pdp_ip0", "pdp_ip1", "pdp_ip2", "pdp_ip3"]
    static let supported = wifi + wired + cellular
} 

private func ipAddresses() -> [String] {
        var addresses = [String]()
        var ifaddr: UnsafeMutablePointer<ifaddrs>?

        guard getifaddrs(&ifaddr) == 0 else { return addresses }

        var pointer = ifaddr

        while pointer != nil {
            defer { pointer = pointer?.pointee.ifa_next }

            guard
                let interface = pointer?.pointee,
                interface.ifa_addr.pointee.sa_family == UInt8(AF_INET) ||
                    interface.ifa_addr.pointee.sa_family == UInt8(AF_INET6),
                let interfaceName = interface.ifa_name,
                let interfaceNameFormatted = String(cString: interfaceName, encoding: .utf8),
                InterfaceNames.supported.contains(interfaceNameFormatted)
            else { continue }

            var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST))

            getnameinfo(
                interface.ifa_addr,
                socklen_t(interface.ifa_addr.pointee.sa_len),
                &hostname,
                socklen_t(hostname.count),
                nil,
                socklen_t(0),
                NI_NUMERICHOST
            )

            if let formattedIpAddress = String(cString: hostname, encoding: .utf8), !formattedIpAddress.isEmpty {
                addresses.append(formattedIpAddress)
            }
        }

        freeifaddrs(ifaddr)
        return addresses
    }

network_interface_objc.m

// Code adapted from https://stackoverflow.com/a/6807801
- (NSArray *)ipAddresses {
    NSMutableArray *addresses = [[NSMutableArray alloc] init];
    struct ifaddrs *interfaces = NULL;
    struct ifaddrs *temp_addr = NULL;
    int success = 0;
    // retrieve the current interfaces - returns 0 on success
    success = getifaddrs(&interfaces);
    if (success == 0) {
        // Loop through linked list of interfaces
        temp_addr = interfaces;
        while(temp_addr != NULL) {
            if(temp_addr->ifa_addr->sa_family == AF_INET) {
                // Skip the loopback interface, it's always the same.
                if ([[NSString stringWithUTF8String: temp_addr->ifa_name] isEqualToString: @"lo0"]) {
                    temp_addr = temp_addr->ifa_next;
                    continue;
                }

                NSString *address = [NSString stringWithUTF8String: inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];

                [addresses addObject: address];
            }

            temp_addr = temp_addr->ifa_next;
        }
    }
    // Free memory
    freeifaddrs(interfaces);

    return [addresses copy];
}