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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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*/
/**
* @test
* @bug 6296125
* @summary JDI: Disabling an EventRequest can cause a multi-threaded debuggee to hang
*
* @author jjh
*
* @modules jdk.jdi
* @run build TestScaffold VMConnection TargetListener TargetAdapter
* @run compile -g TwoThreadsTest.java
* @run driver TwoThreadsTest
*/
import com.sun.jdi.*;
import com.sun.jdi.event.*;
import com.sun.jdi.request.*;
import java.util.*;
/*
* This debuggee basically runs two threads each of
* which loop, hitting a bkpt in each iteration.
*
*/
class TwoThreadsTarg extends Thread {
static boolean one = false;
static String name1 = "Thread 1";
static String name2 = "Thread 2";
static int count = 100;
public static void main(String[] args) {
System.out.println("Howdy!");
TwoThreadsTarg t1 = new TwoThreadsTarg(name1);
TwoThreadsTarg t2 = new TwoThreadsTarg(name2);
t1.start();
t2.start();
}
public TwoThreadsTarg(String name) {
super(name);
}
public void run() {
if (getName().equals(name1)) {
run1();
} else {
run2();
}
}
public void bkpt1(int i) {
yield();
}
public void run1() {
int i = 0;
while (i < count) {
i++;
bkpt1(i);
}
}
public void bkpt2(int i) {
yield();
}
public void run2() {
int i = 0;
while (i < count) {
i++;
bkpt2(i);
}
}
}
/********** test program **********/
public class TwoThreadsTest extends TestScaffold {
ReferenceType targetClass;
ThreadReference mainThread;
BreakpointRequest request1;
BreakpointRequest request2;
static volatile int bkpts = 0;
Thread timerThread;
static int waitTime = 20000;
TwoThreadsTest (String args[]) {
super(args);
}
public static void main(String[] args) throws Exception {
new TwoThreadsTest(args).startTests();
}
/* BreakpointEvent handler */
public void breakpointReached(BreakpointEvent event) {
if (bkpts == 0) {
/*
* This thread will watch for n secs to go by with no
* calls to this method.
*/
timerThread.start();
}
synchronized("abc") {
/*
* Note that this will most likely never get to
* the number of times the two bkpt lines in the debuggee
* are hit because bkpts are lost while they are disabled.
*/
bkpts++;
}
/*
* The bug occurs when the requests are disabled
* and then re-enabled during the event handler.
*/
request1.disable();
request2.disable();
/*
* This code between the disables and enables
* is just filler that leaves the requests disabled
* for awhile. I suppose a sleep could be used instead
*/
Method mmm = event.location().method();
List lvlist;
try {
lvlist = mmm.variablesByName("i");
} catch (AbsentInformationException ee) {
failure("FAILED: can't get local var i");
return;
}
LocalVariable ivar = (LocalVariable)lvlist.get(0);
ThreadReference thr = event.thread();
StackFrame sf;
try {
sf = thr.frame(0);
} catch (IncompatibleThreadStateException ee) {
failure("FAILED: bad thread state");
return;
}
Value ival = sf.getValue(ivar);
println("Got bkpt at: " + event.location() + ", i = " + ival);
request1.enable();
request2.enable();
}
/********** test core **********/
protected void runTests() throws Exception {
/*
* Get to the top of main()
* to determine targetClass and mainThread
*/
BreakpointEvent bpe = startToMain("TwoThreadsTarg");
targetClass = bpe.location().declaringType();
mainThread = bpe.thread();
EventRequestManager erm = vm().eventRequestManager();
final Thread mainThread = Thread.currentThread();
/*
* Set event requests
*/
Location loc1 = findMethod(targetClass, "bkpt1", "(I)V").location();
Location loc2 = findMethod(targetClass, "bkpt2", "(I)V").location();
request1 = erm.createBreakpointRequest(loc1);
request2 = erm.createBreakpointRequest(loc2);
request1.enable();
request2.enable();
/*
* This thread will be started when we get the first bkpt.
* (Which we always expect to get).
* It awakens every n seconds and checks to see if we
* got any breakpoint events while it was asleep.
*/
timerThread = new Thread("test timer") {
public void run() {
int myBkpts = bkpts;
while (true) {
try {
Thread.sleep(waitTime);
System.out.println("bkpts = " + bkpts);
if (myBkpts == bkpts) {
// no bkpt for 'waitTime' secs
failure("failure: Debuggee appears to be hung");
vmDisconnected = true;
// This awakens the main thread which is
// waiting for a VMDisconnect.
mainThread.interrupt();
break;
}
myBkpts = bkpts;
} catch (InterruptedException ee) {
// If the test completes, this occurs.
println("timer Interrupted");
break;
}
}
}
};
/*
* resume the target, listening for events
*/
listenUntilVMDisconnect();
timerThread.interrupt();
/*
* deal with results of test
* if anything has called failure("foo") testFailed will be true
*/
if (!testFailed) {
println("TwoThreadsTest: passed; bkpts = " + bkpts);
} else {
throw new Exception("TwoThreadsTest: failed; bkpts = " + bkpts);
}
}
}