001//
002// JODConverter - Java OpenDocument Converter
003// Copyright 2009 Art of Solving Ltd
004// Copyright 2004-2009 Mirko Nasato
005//
006// JODConverter is free software: you can redistribute it and/or
007// modify it under the terms of the GNU Lesser General Public License
008// as published by the Free Software Foundation, either version 3 of
009// the License, or (at your option) any later version.
010//
011// JODConverter is distributed in the hope that it will be useful,
012// but WITHOUT ANY WARRANTY; without even the implied warranty of
013// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014// Lesser General Public License for more details.
015//
016// You should have received a copy of the GNU Lesser General
017// Public License along with JODConverter.  If not, see
018// <http://www.gnu.org/licenses/>.
019//
020package org.nuxeo.launcher.process;
021
022import static java.nio.charset.StandardCharsets.UTF_8;
023
024import java.io.IOException;
025import java.util.List;
026import java.util.regex.Matcher;
027import java.util.regex.Pattern;
028
029import org.apache.commons.io.IOUtils;
030
031/**
032 * {@link ProcessManager} implementation for *nix systems. Uses the <tt>ps</tt> and <tt>kill</tt> commands.
033 * <p>
034 * Works for Linux. Works for Solaris too, except that the command line string returned by <tt>ps</tt> there is limited
035 * to 80 characters and this affects {@link #findPid(String)}.
036 */
037public class UnixProcessManager implements ProcessManager {
038
039    protected static final boolean PID_ENABLED = true;
040
041    private static final Pattern PS_OUTPUT_LINE = Pattern.compile("^\\s*(\\d+)\\s+(.*)$");
042
043    protected String[] psCommand() {
044        return new String[] { "/bin/ps", "-e", "-o", "pid,args" };
045    }
046
047    @Override
048    public String findPid(String regex) throws IOException {
049        Pattern commandPattern = Pattern.compile(regex);
050        for (String line : execute(psCommand())) {
051            Matcher lineMatcher = PS_OUTPUT_LINE.matcher(line);
052            if (lineMatcher.matches()) {
053                String command = lineMatcher.group(2);
054                Matcher commandMatcher = commandPattern.matcher(command);
055                if (commandMatcher.find()) {
056                    return lineMatcher.group(1);
057                }
058            }
059        }
060        return null;
061    }
062
063    @Override
064    public void kill(Process process, String pid) throws IOException {
065        execute("/bin/kill", "-KILL", pid);
066    }
067
068    private List<String> execute(String... command) throws IOException {
069        Process process = new ProcessBuilder(command).start();
070        return IOUtils.readLines(process.getInputStream(), UTF_8);
071    }
072
073    @Override
074    public boolean canFindPid() {
075        return PID_ENABLED;
076    }
077
078}