Add UDP support to dart:io

tests/standalone/io/raw_datagram_socket_test.dart

Index: tests/standalone/io/raw_datagram_socket_test.dart
diff --git a/tests/standalone/io/raw_datagram_socket_test.dart b/tests/standalone/io/raw_datagram_socket_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..084416dd4c556d179c73afcd035e29b777db623b
--- /dev/null
+++ b/tests/standalone/io/raw_datagram_socket_test.dart
@@ -0,0 +1,148 @@
+// 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.
+
+import "dart:async";
+import "dart:io";
+import "dart:typed_data";
+
+import "package:expect/expect.dart";
+
+testDatagramSocketOptions() {
+  var socket = new RawDatagramSocket(InternetAddress.LOOPBACK_IP_V4, 0);
+  Expect.isTrue(socket.multicastLoopback);
+  Expect.equals(1, socket.multicastTTL);
+  Expect.isFalse(socket.broadcastEnabled);
+
+  socket.multicastLoopback = false;
+  socket.multicastTTL = 4;
+  socket.broadcastEnabled = true;
+  Expect.isFalse(socket.multicastLoopback);
+  Expect.equals(4, socket.multicastTTL);
+  Expect.isTrue(socket.broadcastEnabled);
+
+  socket.multicastLoopback = true;
+  socket.multicastTTL = 1;
+  socket.broadcastEnabled = false;
+  Expect.isTrue(socket.multicastLoopback);
+  Expect.equals(1, socket.multicastTTL);
+  Expect.isFalse(socket.broadcastEnabled);
+}
+
+
+testSendReceive(InternetAddress bindAddress) {
+  var total = 10;
+
+  int receivedSeq = 0;
+  var ackSeq = 0;
+  Timer ackTimer;
+
+  var sender = new RawDatagramSocket(bindAddress, 0);
+  var receiver = new RawDatagramSocket(bindAddress, 0);
+  if (bindAddress.isMulticast) {
+    sender.multicastLoopback = true;
+    receiver.multicastLoopback = true;
+    sender.join(bindAddress);
+    receiver.join(bindAddress);
+  }
+
+  UInt8List createDataPackage(int seq) {
+    var data = new Uint8List(1000);
+    (new ByteData.view(data.buffer, 0, 4)).setUint32(0, seq);
+    return data;
+  }
+
+  UInt8List createAckPackage(int seq) {
+    var data = new Uint8List(4);
+    new ByteData.view(data.buffer, 0, 4).setUint32(0, seq);
+    return data;
+  }
+
+  int packageSeq(Datagram datagram) =>
+      new ByteData.view(datagram.data.buffer).getUint32(0);
+
+  void sendData(int seq) {
+    print("sending $seq (${bindAddress.isMulticast})");
+    // Send a datagram acknowledging the received sequence.
+    sender.send(
+        new Datagram(createDataPackage(seq), bindAddress, receiver.port));
+  }
+
+  void sendAck(address, port) {
+    // Send a datagram acknowledging the received sequence.
+    receiver.send(
+        new Datagram(createAckPackage(receivedSeq), address, port));
+    // Start a "long" timer for more data.
+    if (ackTimer != null) ackTimer.cancel();
+    ackTimer = new Timer.periodic(
+        new Duration(milliseconds: 100), (_) => sendAck(address, port));
+  }
+
+  sender.listen((event) {
+    switch (event) {
+      case RawSocketEvent.READ:
+        var datagram = sender.receive();
+        if (datagram != null) {
+          Expect.equals(datagram.port, receiver.port);
+          if (!bindAddress.isMulticast) {
+            Expect.equals(datagram.address, receiver.address);
+          }
+          ackSeq = packageSeq(datagram);
+          if (ackSeq < total) {
+            sender.writeEventsEnabled = true;
+          } else {
+            sender.close();
+            receiver.close();
+            ackTimer.cancel();
+          }
+        }
+        break;
+      case RawSocketEvent.WRITE:
+        // Send the next package.
+        sendData(ackSeq + 1);
+        break;
+      case RawSocketEvent.CLOSED:
+        break;
+      default:
+        throw "Unexpected event $event";
+    }
+  });
+
+  receiver.writeEventsEnabled = false;
+  receiver.listen((event) {
+    switch (event) {
+      case RawSocketEvent.READ:
+        var datagram = receiver.receive();
+        if (datagram != null) {
+          Expect.equals(datagram.port, sender.port);
+          if (!bindAddress.isMulticast) {
+            Expect.equals(datagram.address, receiver.address);
+          }
+          var seq = packageSeq(datagram);
+          if (seq == receivedSeq + 1) {
+            receivedSeq = seq;
+            sendAck(bindAddress, sender.port);
+          }
+        }
+        break;
+      case RawSocketEvent.WRITE:
+        throw "Unexpected WRITE";
+        break;
+      case RawSocketEvent.CLOSED:
+        break;
+      default:
+        throw "Unexpected event $event";
+    }
+  });
+}
+
+
+main() {
+  testDatagramSocketOptions();
+
+  var local = new InternetAddress('172.28.168.197');
+  testSendReceive(local);
+
+  var multicast = new InternetAddress("224.0.0.0");
+  testSendReceive(multicast);
+}