/*
* NOTE: This copyright does *not* cover user programs that use HQ
* program services by normal system calls through the application
* program interfaces provided as part of the Hyperic Plug-in Development
* Kit or the Hyperic Client Development Kit - this is merely considered
* normal use of the program, and does *not* fall under the heading of
* "derived work".
*
* Copyright (C) [2004, 2005, 2006], Hyperic, Inc.
* This file is part of HQ.
*
* HQ is free software; you can redistribute it and/or modify
* it under the terms version 2 of the GNU General Public License as
* published by the Free Software Foundation. This program 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 for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA.
*/
/*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Ant", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package org.hyperic.util.exec;
/**
* Destroys a process running for too long.
* For example:
* <pre>
* ExecuteWatchdog watchdog = new ExecuteWatchdog(30000);
* Execute exec = new Execute(myloghandler, watchdog);
* exec.setCommandLine(mycmdline);
* int exitvalue = exec.execute();
* if (exitvalue != SUCCESS && watchdog.killedProcess()){
* // it was killed on purpose by the watchdog
* }
* </pre>
* @author thomas.haas@softwired-inc.com
* @author <a href="mailto:sbailliez@imediation.com">Stephane Bailliez</a>
* @see Execute
*/
public class ExecuteWatchdog implements Runnable {
/** the process to execute and watch for duration */
private Process process;
/** timeout duration. Once the process running time exceeds this it should be killed */
private int timeout;
/** say whether or not the watchog is currently monitoring a process */
private boolean watch = false;
/** exception that might be thrown during the process execution */
private Exception caught = null;
/** say whether or not the process was killed due to running overtime */
private boolean killedProcess = false;
Thread execThread;
private boolean dontkill=false;
/**
* Creates a new watchdog with a given timeout.
*
* @param timeout the timeout for the process in milliseconds. It must be greather than 0.
*/
public ExecuteWatchdog(int timeout) {
if (timeout < 1) {
throw new IllegalArgumentException("timeout lesser than 1.");
}
this.timeout = timeout;
}
public void setDontkill( boolean b ) {
dontkill=b;
}
/**
* Watches the given process and terminates it, if it runs for too long.
* All information from the previous run are reset.
* @param process the process to monitor. It cannot be <tt>null</tt>
* @throws IllegalStateException thrown if a process is still being monitored.
*/
public synchronized void start(Process process, Thread execThread) {
if (process == null) {
throw new NullPointerException("process is null.");
}
if (this.process != null) {
throw new IllegalStateException("Already running.");
}
this.caught = null;
this.killedProcess = false;
this.watch = true;
this.process = process;
final Thread thread = new Thread(this, "WATCHDOG");
this.execThread=execThread;
thread.setDaemon(true);
thread.start();
}
/**
* Stops the watcher. It will notify all threads possibly waiting on this object.
*/
public synchronized void stop() {
watch = false;
notifyAll();
}
/**
* Watches the process and terminates it, if it runs for to long.
*/
public synchronized void run() {
try {
// This isn't a Task, don't have a Project object to log.
// project.log("ExecuteWatchdog: timeout = "+timeout+" msec", Project.MSG_VERBOSE);
final long until = System.currentTimeMillis() + timeout;
long now;
while (watch && until > (now = System.currentTimeMillis())) {
try {
wait(until - now);
} catch (InterruptedException e) {}
}
// if we are here, either someone stopped the watchdog,
// we are on timeout and the process must be killed, or
// we are on timeout and the process has already stopped.
try {
// We must check if the process was not stopped
// before being here
process.exitValue();
} catch (IllegalThreadStateException e){
// the process is not terminated, if this is really
// a timeout and not a manual stop then kill it.
//System.out.println("ExecuteWatchdog: timeout");
if (watch){
killedProcess = true;
if( ! dontkill ) {
//System.out.println("ExecuteWatchdog: destroying process");
process.destroy();
}
if( execThread != null ) {
execThread.interrupt();
}
}
}
} catch(Exception e) {
caught = e;
} finally {
cleanUp();
}
//System.out.println("ExecuteWatchdog: done");
}
/**
* reset the monitor flag and the process.
*/
protected void cleanUp() {
watch = false;
process = null;
}
/**
* This method will rethrow the exception that was possibly caught during the
* run of the process. It will only remains valid once the process has been
* terminated either by 'error', timeout or manual intervention. Information
* will be discarded once a new process is ran.
* @throws BuildException a wrapped exception over the one that was silently
* swallowed and stored during the process run.
*/
// public void checkException() throws BuildException {
// if (caught != null) {
// throw new BuildException("Exception in ExecuteWatchdog.run: "
// + caught.getMessage(), caught);
// }
// }
public Exception getException() {
return caught;
}
/**
* Indicates whether or not the watchdog is still monitoring the process.
* @return <tt>true</tt> if the process is still running, otherwise <tt>false</tt>.
*/
public boolean isWatching(){
return watch;
}
/**
* Indicates whether the last process run was killed on timeout or not.
* @return <tt>true</tt> if the process was killed otherwise <tt>false</tt>.
*/
public boolean killedProcess(){
return killedProcess;
}
}