From 46344dd0b1ebcd658a17559955d5d7fdbff41630 Mon Sep 17 00:00:00 2001
From: Mike Hearn <mike@plan99.net>
Date: Wed, 21 Jan 2015 16:22:46 +0100
Subject: [PATCH] PeerGroup: fix the IPv6 routing failure detection which was
 broken by a recent change and improve logging in a bunch of places.

---
 .../org/bitcoinj/core/PeerEventListener.java  |  3 ++-
 .../java/org/bitcoinj/core/PeerGroup.java     | 20 ++++++++++++-------
 .../bitcoinj/net/ClientConnectionManager.java |  3 ++-
 3 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/core/src/main/java/org/bitcoinj/core/PeerEventListener.java b/core/src/main/java/org/bitcoinj/core/PeerEventListener.java
index 31f4e538..a711491c 100644
--- a/core/src/main/java/org/bitcoinj/core/PeerEventListener.java
+++ b/core/src/main/java/org/bitcoinj/core/PeerEventListener.java
@@ -65,7 +65,8 @@ public interface PeerEventListener {
     /**
      * Called when a peer is disconnected. Note that this won't be called if the listener is registered on a
      * {@link PeerGroup} and the group is in the process of shutting down. If this listener is registered to a
-     * {@link Peer} instead of a {@link PeerGroup}, peerCount will always be 0.
+     * {@link Peer} instead of a {@link PeerGroup}, peerCount will always be 0. This handler can be called without
+     * a corresponding invocation of onPeerConnected if the initial connection is never successful.
      *
      * @param peer
      * @param peerCount the total number of connected peers
diff --git a/core/src/main/java/org/bitcoinj/core/PeerGroup.java b/core/src/main/java/org/bitcoinj/core/PeerGroup.java
index 1c911cd8..4969fe3a 100644
--- a/core/src/main/java/org/bitcoinj/core/PeerGroup.java
+++ b/core/src/main/java/org/bitcoinj/core/PeerGroup.java
@@ -18,6 +18,7 @@
 package org.bitcoinj.core;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.*;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Lists;
@@ -1169,10 +1170,15 @@ public class PeerGroup implements TransactionBroadcaster {
         pendingPeers.add(peer);
 
         try {
-            channels.openConnection(address.toSocketAddress(), peer);
-        } catch (Exception e) {
-            log.warn("Failed to connect to " + address + ": " + e.getMessage());
-            handlePeerDeath(peer, e);
+            log.info("Attempting connection to {}     ({} connected, {} pending, {} max)", address,
+                    peers.size(), pendingPeers.size(), maxConnections);
+            ListenableFuture<SocketAddress> future = channels.openConnection(address.toSocketAddress(), peer);
+            if (future.isDone())
+                Uninterruptibles.getUninterruptibly(future);
+        } catch (ExecutionException e) {
+            Throwable cause = Throwables.getRootCause(e);
+            log.warn("Failed to connect to " + address + ": " + cause.getMessage());
+            handlePeerDeath(peer, cause);
             return null;
         }
         peer.setSocketTimeout(connectTimeoutMillis);
@@ -1245,10 +1251,10 @@ public class PeerGroup implements TransactionBroadcaster {
             backoffMap.get(peer.getAddress()).trackSuccess();
 
             // Sets up the newly connected peer so it can do everything it needs to.
-            log.info("{}: New peer", peer);
             pendingPeers.remove(peer);
             peers.add(peer);
             newSize = peers.size();
+            log.info("{}: New peer      ({} connected, {} pending, {} max)", peer, newSize, pendingPeers.size(), maxConnections);
             // Give the peer a filter that can be used to probabilistically drop transactions that
             // aren't relevant to our wallet. We may still receive some false positives, which is
             // OK because it helps improve wallet privacy. Old nodes will just ignore the message.
@@ -1386,7 +1392,7 @@ public class PeerGroup implements TransactionBroadcaster {
         }
     }
 
-    protected void handlePeerDeath(final Peer peer, @Nullable Exception exception) {
+    protected void handlePeerDeath(final Peer peer, @Nullable Throwable exception) {
         // Peer deaths can occur during startup if a connect attempt after peer discovery aborts immediately.
         if (!isRunning()) return;
 
@@ -1417,7 +1423,7 @@ public class PeerGroup implements TransactionBroadcaster {
 
             groupBackoff.trackFailure();
 
-            if (!(exception instanceof NoRouteToHostException)) {
+            if (exception instanceof NoRouteToHostException) {
                 if (address.getAddr() instanceof Inet6Address && !ipv6Unreachable) {
                     ipv6Unreachable = true;
                     log.warn("IPv6 peer connect failed due to routing failure, ignoring IPv6 addresses from now on");
diff --git a/core/src/main/java/org/bitcoinj/net/ClientConnectionManager.java b/core/src/main/java/org/bitcoinj/net/ClientConnectionManager.java
index e4dd5a77..8027023d 100644
--- a/core/src/main/java/org/bitcoinj/net/ClientConnectionManager.java
+++ b/core/src/main/java/org/bitcoinj/net/ClientConnectionManager.java
@@ -30,7 +30,8 @@ import java.net.SocketAddress;
  */
 public interface ClientConnectionManager extends Service {
     /**
-     * Creates a new connection to the given address, with the given parser used to handle incoming data.
+     * Creates a new connection to the given address, with the given parser used to handle incoming data. Any errors
+     * that occur during connection will be returned in the given future, including errors that can occur immediately.
      */
     ListenableFuture<SocketAddress> openConnection(SocketAddress serverAddress, StreamParser parser);