Ensure EpollSocketChannel.localAddress() returns correct address after connect(...) call.

Motivation:

We missed to correctly retrieve the localAddress() after we called Socket.connect(..) and so the user would always see an incorrect address when calling EpollSocketChannel.localAddress().

Modifications:

- Ensure we always retrieve the localAddress() after we called Socket.connect(...) as only after this we will be able to receive the correct address.
- Add unit test

Result:

Correct and consistent behaviour across different transports (NIO/OIO/EPOLL).

testsuite/src/main/java/io/netty/testsuite/transport/socket/SocketConnectTest.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.testsuite.transport.socket;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.util.concurrent.ImmediateEventExecutor;
+import io.netty.util.concurrent.Promise;
+import org.junit.Test;
+
+import java.net.InetSocketAddress;
+
+import static org.junit.Assert.*;
+
+public class SocketConnectTest extends AbstractSocketTest {
+
+    @Test(timeout = 30000)
+    public void testLocalAddressAfterConnect() throws Throwable {
+        run();
+    }
+
+    public void testLocalAddressAfterConnect(ServerBootstrap sb, Bootstrap cb) throws Throwable {
+        Channel serverChannel = null;
+        Channel clientChannel = null;
+        try {
+            final Promise<InetSocketAddress> localAddressPromise = ImmediateEventExecutor.INSTANCE.newPromise();
+            serverChannel = sb.childHandler(new ChannelInboundHandlerAdapter() {
+                        @Override
+                        public void channelActive(ChannelHandlerContext ctx) throws Exception {
+                            localAddressPromise.setSuccess((InetSocketAddress) ctx.channel().localAddress());
+                        }
+                    }).bind().syncUninterruptibly().channel();
+
+            clientChannel = cb.handler(new ChannelInboundHandlerAdapter()).register().syncUninterruptibly().channel();
+
+            assertNull(clientChannel.localAddress());
+            assertNull(clientChannel.remoteAddress());
+
+            clientChannel.connect(serverChannel.localAddress()).syncUninterruptibly().channel();
+            assertLocalAddress((InetSocketAddress) clientChannel.localAddress());
+            assertNotNull(clientChannel.remoteAddress());
+
+            assertLocalAddress(localAddressPromise.get());
+        } finally {
+            if (clientChannel != null) {
+                clientChannel.close().syncUninterruptibly();
+            }
+            if (serverChannel != null) {
+                serverChannel.close().syncUninterruptibly();
+            }
+        }
+    }
+
+    private static void assertLocalAddress(InetSocketAddress address) {
+        assertTrue(address.getPort() > 0);
+        assertFalse(address.getAddress().isAnyLocalAddress());
+    }
+}

transport-native-epoll/src/main/java/io/netty/channel/epoll/EpollSocketChannel.java

@@ -179,21 +179,21 @@ public final class EpollSocketChannel extends AbstractEpollStreamChannel impleme
         if (localAddress != null) {
             checkResolvable((InetSocketAddress) localAddress);
         }
-        // We always need to set the localAddress even if not connected yet
+        InetSocketAddress remoteAddr = (InetSocketAddress) remoteAddress;
+        checkResolvable(remoteAddr);
+
+        boolean connected = super.doConnect(remoteAddress, localAddress);
+        if (connected) {
+            remote = computeRemoteAddr(remoteAddr, fd().remoteAddress());
+        } else {
+            // Store for later usage in doFinishConnect()
+            requestedRemote = remoteAddr;
+        }
+        // We always need to set the localAddress even if not connected yet as the bind already took place.
         //
         // See https://github.com/netty/netty/issues/3463
         local = fd().localAddress();
-
-        InetSocketAddress remoteAddr = (InetSocketAddress) remoteAddress;
-        checkResolvable(remoteAddr);
-        if (super.doConnect(remoteAddress, localAddress)) {
-            remote = computeRemoteAddr(remoteAddr, fd().remoteAddress());
-            return true;
-        }
-
-        // Store for later usage in doFinishConnect()
-        requestedRemote = remoteAddr;
-        return false;
+        return connected;
     }
 
     private final class EpollSocketChannelUnsafe extends EpollStreamUnsafe {

transport-native-epoll/src/test/java/io/netty/channel/epoll/EpollSocketConnectTest.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2016 The Netty Project
+ *
+ * The Netty Project licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+package io.netty.channel.epoll;
+
+import io.netty.bootstrap.Bootstrap;
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.testsuite.transport.TestsuitePermutation;
+import io.netty.testsuite.transport.socket.SocketConnectTest;
+
+import java.util.List;
+
+public class EpollSocketConnectTest extends SocketConnectTest {
+
+    @Override
+    protected List<TestsuitePermutation.BootstrapComboFactory<ServerBootstrap, Bootstrap>> newFactories() {
+        return EpollSocketTestPermutation.INSTANCE.socket();
+    }
+}