jdk/test/com/sun/jdi/TwoThreadsTest.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/com/sun/jdi/TwoThreadsTest.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,245 @@
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * 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).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/**
+ *  @test
+ *  @bug 6296125
+ *  @summary  JDI: Disabling an EventRequest can cause a multi-threaded debuggee to hang
+ *
+ *  @author jjh
+ *
+ *  @run build TestScaffold VMConnection TargetListener TargetAdapter
+ *  @run compile -g TwoThreadsTest.java
+ *  @run main 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);
+        }
+    }
+}