Add new InternetAddress class with a static lookup function (including IPv6 results).

sdk/lib/io/socket.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
+
+class InternetAddressType {
+  static const InternetAddressType IPv4 = const InternetAddressType._(0);
+  static const InternetAddressType IPv6 = const InternetAddressType._(1);
+  static const InternetAddressType ANY = const InternetAddressType._(-1);
+
+  final int _value;
+
+  const InternetAddressType._(String this._value);
+
+  String get name {
+    switch (_value) {
+      case -1: return "ANY";
+      case 0: return "IPv4";
+      case 1: return "IPv6";
+      default: throw new ArgumentError("Invalid InternetAddress");
+    }
+  }
+
+  String toString() => "InternetAddressType($name)";
+
+  int get hashCode => _value;
+
+  bool operator==(other) => _value == other._value;
+}
+
+abstract class InternetAddress {
+  InternetAddressType type;
+  String get address;
+  String get host;
+
+  external static Future<List<InternetAddress>> lookup(
+      String host, {InternetAddressType type: InternetAddressType.ANY});
+}
+
 /**
  * The RawServerSocket is a server socket, providing a stream of low-level
  * [RawSocket]s.
  *
  * See [RawSocket] for more info.
  */
 abstract class RawServerSocket implements Stream<RawSocket> {
   /**
    * Returns a future for a [:RawServerSocket:]. When the future
    * completes the server socket is bound to the given [address] and
@@ skipping 120 matching lines @@
 
 /**
  * The [RawSocket] is a low-level interface to a socket, exposing the raw
  * events signaled by the system. It's a [Stream] of [RawSocketEvent]s.
  */
 abstract class RawSocket implements Stream<RawSocketEvent> {
   /**
    * Creates a new socket connection to the host and port and returns a [Future]
    * that will complete with either a [RawSocket] once connected or an error
    * if the host-lookup or connection failed.
+   *
+   * [host] can either be a [String] or an [InternetAddress]. If [host] is a
+   * [String], [connect] will perform a [InternetAddress.lookup] and use
+   * the first value in the list.
    */
-  external static Future<RawSocket> connect(String host, int port);
+  external static Future<RawSocket> connect(host, int port);
 
   /**
    * Returns the number of received and non-read bytes in the socket that
    * can be read.
    */
   int available();
 
   /**
    * Read up to [len] bytes from the socket. This function is
    * non-blocking and will only return data if data is available. The
@@ skipping 15 matching lines @@
    * Returns the port used by this socket.
    */
   int get port;
 
   /**
    * Returns the remote port connected to by this socket.
    */
   int get remotePort;
 
   /**
-   * Returns the host used to connect this socket.
+   * Returns the [InternetAddress] used to connect this socket.
    */
-  String get host;
+  InternetAddress get address;
 
   /**
    * Returns the remote host connected to by this socket.
    */
   String get remoteHost;
 
   /**
    * Closes the socket. Calling [close] will never throw an exception
    * and calling it several times is supported. Calling [close] can result in
    * a [RawSocketEvent.READ_CLOSED] event.
@@ skipping 34 matching lines @@
 /**
  * A high-level class for communicating over a TCP socket. The [Socket] exposes
  * both a [Stream] and a [IOSink] interface, making it ideal for
  * using together with other [Stream]s.
  */
 abstract class Socket implements Stream<List<int>>, IOSink {
   /**
    * Creats a new socket connection to the host and port and returns a [Future]
    * that will complete with either a [Socket] once connected or an error
    * if the host-lookup or connection failed.
+   *
+   * [host] can either be a [String] or an [InternetAddress]. If [host] is a
+   * [String], [connect] will perform a [InternetAddress.lookup] and use
+   * the first value in the list.
    */
-  external static Future<Socket> connect(String host, int port);
+  external static Future<Socket> connect(host, int port);
 
   /**
    * Destroy the socket in both directions. Calling [destroy] will make the
    * send a close event on the stream and will no longer react on data being
    * piped to it.
    *
    * Call [close](inherited from [IOSink]) to only close the [Socket]
    * for sending data.
    */
   void destroy();
@@ skipping 10 matching lines @@
    * Returns the port used by this socket.
    */
   int get port;
 
   /**
    * Returns the remote port connected to by this socket.
    */
   int get remotePort;
 
   /**
-   * Returns the host used to connect this socket.
+   * Returns the [InternetAddress] used to connect this socket.
    */
-  String get host;
+  InternetAddress get address;
 
   /**
    * Returns the remote host connected to by this socket.
    */
   String get remoteHost;
 }
 
 
 class SocketIOException implements Exception {
   const SocketIOException([String this.message = "",
                            OSError this.osError = null]);
   String toString() {
     StringBuffer sb = new StringBuffer();
     sb.write("SocketIOException");
     if (!message.isEmpty) {
       sb.write(": $message");
       if (osError != null) {
         sb.write(" ($osError)");
       }
     } else if (osError != null) {
       sb.write(": $osError");
     }
     return sb.toString();
   }
   final String message;
   final OSError osError;
 }