From 3ded023629e1d90365d95e2857230a8086d4e67a Mon Sep 17 00:00:00 2001
From: Florian Schmaus <flo@geekplace.eu>
Date: Sat, 16 Mar 2019 10:27:18 +0100
Subject: [PATCH] Remove 'synchronized' from notifyConnectionError()

as it is not neccessary and causes stalls and deadlocks with a
concurrent connect()/login() (which could be resolved interrupting the
connect()/login() calling thread):

"Smack Reader (0)" daemon prio=5 tid=21 Blocked
  | group="main" sCount=1 dsCount=0 obj=0x12c84670 self=0x7e072ca200
  | sysTid=14965 nice=0 cgrp=default sched=0/0 handle=0x7e06155450
  | state=S schedstat=( 63430626 3034269 21 ) utm=5 stm=0 core=2 HZ=100
  | stack=0x7e06053000-0x7e06055000 stackSize=1037KB
  | held mutexes=
  at org.jivesoftware.smack.tcp.XMPPTCPConnection.notifyConnectionError(XMPPTCPConnection.java:-1)
  - waiting to lock <0x0ec6e6bb> (a org.jivesoftware.smack.tcp.XMPPTCPConnection) held by thread 22
  at org.jivesoftware.smack.tcp.XMPPTCPConnection.access$3900(XMPPTCPConnection.java:154)
  at org.jivesoftware.smack.tcp.XMPPTCPConnection$PacketReader.parsePackets(XMPPTCPConnection.java:1330)
  at org.jivesoftware.smack.tcp.XMPPTCPConnection$PacketReader.access$900(XMPPTCPConnection.java:1064)
  at org.jivesoftware.smack.tcp.XMPPTCPConnection$PacketReader$1.run(XMPPTCPConnection.java:1081)
  at java.lang.Thread.run(Thread.java:761)

"connect" prio=5 tid=22 Waiting
  | group="main" sCount=1 dsCount=0 obj=0x12c8e820 self=0x7e19bcd600
  | sysTid=15047 nice=0 cgrp=default sched=0/0 handle=0x7e05ee4450
  | state=S schedstat=( 14067083 7475835 14 ) utm=1 stm=0 core=0 HZ=100
  | stack=0x7e05de2000-0x7e05de4000 stackSize=1037KB
  | held mutexes=
  at java.lang.Object.wait!(Native method)
  - waiting on <0x0c058b14> (a java.lang.Object)
  at java.lang.Thread.parkFor$(Thread.java:2127)
  - locked <0x0c058b14> (a java.lang.Object)
  at sun.misc.Unsafe.park(Unsafe.java:325)
  at java.util.concurrent.locks.LockSupport.park(LockSupport.java:161)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:840)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:994)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1303)
  at java.util.concurrent.Semaphore.acquire(Semaphore.java:446)
  at org.jivesoftware.smack.tcp.XMPPTCPConnection.initConnection(XMPPTCPConnection.java:685)
  at org.jivesoftware.smack.tcp.XMPPTCPConnection.connectInternal(XMPPTCPConnection.java:942)
  at org.jivesoftware.smack.AbstractXMPPConnection.connect(AbstractXMPPConnection.java:417)
  - locked <0x0ec6e6bb> (a org.jivesoftware.smack.tcp.XMPPTCPConnection)
  at org.yaxim.androidclient.service.SmackableImp.connectAndLogin(SmackableImp.java:717)
  - locked <0x0ec6e6bb> (a org.jivesoftware.smack.tcp.XMPPTCPConnection)
  at org.yaxim.androidclient.service.SmackableImp.doConnect(SmackableImp.java:304)
  at org.yaxim.androidclient.service.SmackableImp$5.run(SmackableImp.java:391)
---
 .../main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java b/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
index 61de855d6..b0fcb8b7d 100644
--- a/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
+++ b/smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java
@@ -953,7 +953,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
      *
      * @param e the exception that causes the connection close event.
      */
-    private synchronized void notifyConnectionError(final Exception e) {
+    private void notifyConnectionError(final Exception e) {
         ASYNC_BUT_ORDERED.performAsyncButOrdered(this, new Runnable() {
             @Override
             public void run() {