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 java.io.IOException;
023import java.util.List;
024import java.util.regex.Matcher;
025import java.util.regex.Pattern;
026
027import org.apache.commons.io.IOUtils;
028
029/**
030 * {@link ProcessManager} implementation for *nix systems. Uses the <tt>ps</tt> and <tt>kill</tt> commands.
031 * <p>
032 * Works for Linux. Works for Solaris too, except that the command line string returned by <tt>ps</tt> there is limited
033 * to 80 characters and this affects {@link #findPid(String)}.
034 */
035public class UnixProcessManager implements ProcessManager {
036
037    protected static final boolean PID_ENABLED = true;
038
039    private static final Pattern PS_OUTPUT_LINE = Pattern.compile("^\\s*(\\d+)\\s+(.*)$");
040
041    protected String[] psCommand() {
042        return new String[] { "/bin/ps", "-e", "-o", "pid,args" };
043    }
044
045    @Override
046    public String findPid(String regex) throws IOException {
047        Pattern commandPattern = Pattern.compile(regex);
048        for (String line : execute(psCommand())) {
049            Matcher lineMatcher = PS_OUTPUT_LINE.matcher(line);
050            if (lineMatcher.matches()) {
051                String command = lineMatcher.group(2);
052                Matcher commandMatcher = commandPattern.matcher(command);
053                if (commandMatcher.find()) {
054                    return lineMatcher.group(1);
055                }
056            }
057        }
058        return null;
059    }
060
061    @Override
062    public void kill(Process process, String pid) throws IOException {
063        execute("/bin/kill", "-KILL", pid);
064    }
065
066    private List<String> execute(String... command) throws IOException {
067        Process process = new ProcessBuilder(command).start();
068        List<String> lines = IOUtils.readLines(process.getInputStream());
069        return lines;
070    }
071
072    @Override
073    public boolean canFindPid() {
074        return PID_ENABLED;
075    }
076
077}