UNDERTOW-1859 Fix WriteTimeoutTestCase not terminating

[TomasHofman]

https://issues.redhat.com/browse/UNDERTOW-1859

@fl4via for your consideration.

The test doesn't terminate because occasionally int res = response.write(buffer) on line 94 returns 0, which causes the thread to return and not execute the exchange.endExchange(); I think.

[TomasHofman]

The WriteTimeoutTestCase now fails in the "proxy" profile with:

java.lang.RuntimeException: Buffer Leak io.undertow.server.WriteTimeoutTestCase.testWriteTimeout[proxy]
	at io.undertow.testutils.DefaultServer$1.testFinished(DefaultServer.java:403)
	at org.junit.runner.notification.SynchronizedRunListener.testFinished(SynchronizedRunListener.java:87)
	at org.junit.runner.notification.RunNotifier$9.notifyListener(RunNotifier.java:225)
	at org.junit.runner.notification.RunNotifier$SafeNotifier.run(RunNotifier.java:72)
	at org.junit.runner.notification.RunNotifier.fireTestFinished(RunNotifier.java:222)
	at org.junit.internal.runners.model.EachTestNotifier.fireTestFinished(EachTestNotifier.java:38)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:372)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
	at io.undertow.testutils.DefaultServer.runChild(DefaultServer.java:706)
	at io.undertow.testutils.DefaultServer.runChild(DefaultServer.java:144)
	at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
	at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at io.undertow.testutils.RunDefaultServer.evaluate(RunDefaultServer.java:74)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
	at io.undertow.testutils.DefaultServer.run(DefaultServer.java:376)
	at org.junit.runners.Suite.runChild(Suite.java:128)
	at org.junit.runners.Suite.runChild(Suite.java:27)
	at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
	at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
	at org.apache.maven.surefire.junitcore.JUnitCore.run(JUnitCore.java:55)
	at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.createRequestAndRun(JUnitCoreWrapper.java:137)
	at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.executeEager(JUnitCoreWrapper.java:107)
	at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.execute(JUnitCoreWrapper.java:83)
	at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.execute(JUnitCoreWrapper.java:75)
	at org.apache.maven.surefire.junitcore.JUnitCoreProvider.invoke(JUnitCoreProvider.java:158)
	at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:383)
	at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:344)
	at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:125)
	at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:417)
Caused by: java.lang.RuntimeException: java.nio.DirectByteBuffer[pos=0 lim=8192 cap=8192] NO: 188480 [NO_CONTEXT]
	at io.undertow.testutils.DebuggingSlicePool$DebuggingBuffer.<init>(DebuggingSlicePool.java:84)
	at io.undertow.testutils.DebuggingSlicePool.allocate(DebuggingSlicePool.java:45)
	at io.undertow.util.Transfer$TransferListener.handleEvent(Transfer.java:170)
	at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92)
	at io.undertow.channels.DetachableStreamSourceChannel$SetterDelegatingListener.handleEvent(DetachableStreamSourceChannel.java:228)
	at io.undertow.channels.DetachableStreamSourceChannel$SetterDelegatingListener.handleEvent(DetachableStreamSourceChannel.java:215)
	at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92)
	at org.xnio.conduits.ReadReadyHandler$ChannelListenerHandler.readReady(ReadReadyHandler.java:66)
	at org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89)
	at org.xnio.nio.WorkerThread.run(WorkerThread.java:591)

[TomasHofman]

On my laptop the failures don't happen always, but often enough. Running mvn test -Dtest=WriteTimeoutTestCase -f core/ -Pproxy there is several surefire executions (proxy, proxy-https, ...), at least some of those executions fail always.

The "Caused by: java.lang.RuntimeException: ..." portion of the stack trace above shows where the leaking buffer was initialized, and this stack trace is different in various surefire executions, depending on which conduits are configured etc...

So far I don't understand what's causing the leak.