001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019 package org.crsh.shell.impl.command;
020
021 import org.crsh.shell.ShellProcess;
022 import org.crsh.shell.ShellProcessContext;
023 import org.crsh.shell.ShellResponse;
024
025 import java.util.logging.Level;
026
027 abstract class CRaSHProcess implements ShellProcess {
028
029 /** . */
030 protected final CRaSHSession crash;
031
032 /** . */
033 protected final String request;
034
035 /** . */
036 private volatile Thread thread;
037
038 /** . */
039 private volatile boolean cancelled;
040
041 protected CRaSHProcess(CRaSHSession crash, String request) {
042 this.crash = crash;
043 this.request = request;
044 }
045
046 public void execute(ShellProcessContext processContext) {
047 ClassLoader previous = crash.setCRaSHLoader();
048 try {
049 ShellResponse resp;
050 thread = Thread.currentThread();
051
052 //
053 String userName = crash.user != null ? crash.user.getName() : "unauthenticated";
054 CRaSHSession.accessLog.log(Level.FINE, "User " + userName + " executes " + request);
055
056 //
057 try {
058 try {
059 resp = doInvoke(processContext);
060 if (Thread.interrupted() || cancelled) {
061 throw new InterruptedException("like a goto");
062 }
063 }
064 catch (InterruptedException e) {
065 resp = ShellResponse.cancelled();
066 }
067 } catch (Throwable t) {
068 resp = ShellResponse.internalError("Unexpected error when executing process", t);
069 } finally {
070 thread = null;
071 }
072
073 //
074 processContext.end(resp);
075
076 //
077 if (resp instanceof ShellResponse.Error) {
078 ShellResponse.Error error = (ShellResponse.Error)resp;
079 Throwable t = error.getThrowable();
080 if (t != null) {
081 CRaSHSession.log.log(Level.SEVERE, "Error while evaluating request '" + request + "' " + error.getMessage(), t);
082 } else {
083 CRaSHSession.log.log(Level.SEVERE, "Error while evaluating request '" + request + "' " + error.getMessage());
084 }
085 }
086 }
087 finally {
088 crash.setPreviousLoader(previous);
089 }
090 }
091
092 abstract ShellResponse doInvoke(ShellProcessContext context) throws InterruptedException;
093
094 public void cancel() {
095 ClassLoader previous = crash.setCRaSHLoader();
096 try {
097 Thread t = thread;
098 if (t != null) {
099 t.interrupt();
100 }
101 cancelled = true;
102 }
103 finally {
104 crash.setPreviousLoader(previous);
105 }
106 }
107 }