Dépôt officiel du code source de l'ERP OpenConcerto

/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 *

 * Copyright 2011-2019 OpenConcerto, by ILM Informatique. All rights reserved.

 *

 * The contents of this file are subject to the terms of the GNU General Public License Version 3

 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a

 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific

 * language governing permissions and limitations under the License.

 *

 * When distributing the software, include this License Header Notice in each file.

 */

 package org.openconcerto.utils;

import static org.openconcerto.utils.DesktopEnvironment.cmdSubstitution;

import org.openconcerto.utils.cc.ITransformer;

import java.io.BufferedReader;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.IOException;

import java.io.InputStreamReader;

import java.math.BigDecimal;

import java.net.InetAddress;

import java.net.SocketException;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.ArrayList;

import java.util.List;

import java.util.logging.Level;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

/**

 * To abstract differences between platform for non java tasks.

 *

 * @author Sylvain

 * @see DesktopEnvironment

 */

public abstract class Platform {

    public static final String PROCESS_ALLOW_AMBIGUOUS_COMMANDS = "jdk.lang.Process.allowAmbiguousCommands";

    private static final int PING_TIMEOUT = 250;

    public static final Platform getInstance() {

        final OSFamily os = OSFamily.getInstance();

        if (os == OSFamily.Windows) {

            return CYGWIN;

        } else if (os == OSFamily.FreeBSD) {

            return FREEBSD;

        } else if (os == OSFamily.Mac) {

            return MACOS;

        } else {

            return LINUX;

        }

    }

    public static class CannotPassArgumentException extends RuntimeException {

        private final String arg;

        private CannotPassArgumentException(String arg, String message) {

            super("Cannot pass " + arg + message);

            this.arg = arg;

        }

        public final String getArg() {

            return this.arg;

        }

    }

    public abstract boolean supportsPID();

    public abstract boolean isRunning(final int pid) throws IOException;

    public abstract String getPath(final File f);

    public String getPath(final Path p) {

        return this.getPath(p.toFile());

    }

    public String getProcessArg(final String arg) {

        return arg;

    }

    public final String getPID() throws IOException {

        // TODO remove reflection and getPreJava9PID() once on java 11

        try {

            final Class<?> phClass = Class.forName("java.lang.ProcessHandle");

            final Object ph = phClass.getMethod("current").invoke(null);

            return ((Number) phClass.getMethod("pid").invoke(ph)).toString();

        } catch (ClassNotFoundException e) {

            // fall back

        } catch (Exception e) {

            throw new IOException("Couldn't get PID", e);

        }

        return getPreJava9PID();

    }

    protected String getPreJava9PID() throws IOException {

        final Process p = this.eval("echo -n $PPID");

        try (final BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()))) {

            return reader.readLine();

        }

    }

    public final String tail(final File f, final int n) throws IOException {

        final Process p = Runtime.getRuntime().exec(new String[] { "tail", "-n" + n, this.getPath(f) });

        return cmdSubstitution(p);

    }

    protected abstract String getBash();

    /**

     * Create a symbolic link from f2 to f1. NOTE: the path from f2 to f1 is made relative (eg

     * lastLog -> ./allLogs/tuesdayLog).

     *

     * @param f1 the destination of the link, eg "/dir/allLogs/tuesdayLog".

     * @param f2 the name of the link, eg "/dir/lastLog".

     * @throws IOException if an error occurs.

     */

    public final void ln_s(File f1, File f2) throws IOException {

        FileUtils.ln(f1, f2);

    }

    public boolean isSymLink(File f) throws IOException {

        return exitStatus(Runtime.getRuntime().exec(new String[] { "test", "-L", f.getAbsolutePath() })) == 0;

    }

    // see cygwin

    public File getNativeSymlinkFile(File dir) {

        return dir;

    }

    public abstract String readLink(File f) throws IOException;

    public final boolean exists(File f) throws IOException {

        return exitStatus(Runtime.getRuntime().exec(new String[] { "test", "-e", f.getAbsolutePath() })) == 0;

    }

    public final void append(File f1, File f2) throws IOException {

        final String c = "cat '" + f1.getAbsolutePath() + "' >> '" + f2.getAbsolutePath() + "'";

        this.waitForSuccess(this.eval(c), "append");

    }

    public Process cp_l(File src, File dest) throws IOException {

        return Runtime.getRuntime().exec(new String[] { "cp", "-prl", src.getAbsolutePath(), dest.getAbsolutePath() });

    }

    public final boolean ping(InetAddress host) throws IOException {

        return this.ping(host, PING_TIMEOUT);

    }

    /**

     * Test whether that address is reachable.

     *

     * @param host the host to reach.

     * @param timeout the time, in milliseconds, before the call aborts.

     * @return <code>true</code> if the address is reachable.

     * @throws IOException if a network error occurs.

     */

    public abstract boolean ping(InetAddress host, final int timeout) throws IOException;

    public final PingBuilder createPingBuilder() {

        return new PingBuilder(this);

    }

    protected abstract PingResult ping(InetAddress host, final PingBuilder pingBuilder, final int routingTableIndex) throws IOException;

    protected abstract BigDecimal parsePingAverageRT(String statsLine);

    protected final PingResult ping(final String command, final int totalCount, int requiredCount) throws IOException {

        if (requiredCount <= 0)

            requiredCount = totalCount;

        // Keep errors out of cmdSubstitution() (e.g. "ping: sendto: Message too long" when

        // setDontFragment(true))

        final Process proc = evalPB(command).redirectErrorStream(false).start();

        // some programs won't write anything until they read everything

        proc.getOutputStream().close();

        final ByteArrayOutputStream out = new ByteArrayOutputStream(5 * 1024);

        final ByteArrayOutputStream err = new ByteArrayOutputStream(2 * 1024);

        try (final ProcessStreams streams = new ProcessStreams(proc)) {

            streams.start(out, err);

            streams.awaitTermination();

        } catch (Exception e) {

            throw new IllegalStateException("Couldn't capture output of ping", e);

        }

        final String output = out.toString();

        try {

            this.waitForSuccess(proc, "ping");

            final List<String> countAndLastLine = StringUtils.splitIntoLines(output);

            if (countAndLastLine.size() != 2)

                throw new IllegalStateException("Not 2 lines in " + countAndLastLine);

            final int replied = Integer.parseInt(countAndLastLine.get(0));

            assert replied <= totalCount;

            final BigDecimal averageRTT = replied == 0 ? null : parsePingAverageRT(countAndLastLine.get(1).trim());

            return new PingResult(totalCount, replied, requiredCount, averageRTT);

        } catch (Exception e) {

            throw new IllegalStateException("Couldn't use output :<<<\n" + output + "\n<<<\nerr:<<<\n" + err.toString() + "\n<<<", e);

        }

    }

    /**

     * Eval the passed string with bash.

     *

     * @param s a bash script.

     * @return the created process.

     * @throws IOException If an I/O error occurs.

     */

    public final Process eval(String s) throws IOException {

        return evalPB(s).start();

    }

    public final ProcessBuilder evalPB(String s) throws IOException {

        return new ProcessBuilder(this.getBash(), "-c", s);

    }

    public final int exitStatus(Process p) {

        return this.exitStatus(p, null);

    }

    public final int exitStatus(Process p, final String name) {

        try {

            return p.waitFor();

        } catch (InterruptedException e) {

            throw new RTInterruptedException("Interrupted while waiting for" + (name == null ? "" : " '" + name + "'") + " process", e);

        }

    }

    public final void waitForSuccess(final Process p, final String name) {

        final int exitStatus = exitStatus(p, name);

        if (exitStatus != 0)

            throw new IllegalStateException(name + " unsuccessful : " + exitStatus);

    }

    public abstract boolean isAdmin() throws IOException;

    private static abstract class UnixPlatform extends Platform {

        @Override

        public boolean supportsPID() {

            return true;

        }

        @Override

        public final String getPreJava9PID() throws IOException {

            final String symlink = getSelfProcessSymlink();

            if (symlink == null)

                return super.getPreJava9PID();

            // readSymbolicLink() seems to faster than getCanonicalFile() or toRealPath().

            // Another way is using reflection for

            // ManagementFactory.getRuntimeMXBean().jvm.getProcessId()

            return Files.readSymbolicLink(Paths.get(symlink)).getFileName().toString();

        }

        protected abstract String getSelfProcessSymlink();

        public final boolean isRunning(final int pid) throws IOException {

            // --pid only works on Linux, -p also on Nexenta

            final Process p = Runtime.getRuntime().exec(new String[] { "ps", "-p", String.valueOf(pid) });

            return this.exitStatus(p) == 0;

        }

        @Override

        public String getPath(final File f) {

            return f.getPath();

        }

        @Override

        public String getPath(final Path f) {

            return f.toString();

        }

        @Override

        protected String getBash() {

            return "bash";

        }

        @Override

        public String readLink(File f) throws IOException {

            // --no-newline long form not supported on FreeBSD

            final Process p = Runtime.getRuntime().exec(new String[] { "readlink", "-n", f.getAbsolutePath() });

            return cmdSubstitution(p);

        }

        @Override

        public boolean ping(InetAddress host, final int timeout) throws IOException {

            try {

                return host.isReachable(timeout);

            } catch (SocketException e) {

                // On FreeBSD at least, if the destination is blocked by the firewall :

                // java.net.SocketException: Operation not permitted

                // at java.net.Inet4AddressImpl.isReachable0(Native Method)

                // at java.net.Inet4AddressImpl.isReachable(Inet4AddressImpl.java:70)

                Log.get().log(Level.FINER, "Swallow exception", e);

                return false;

            }

        }

        // Linux : rtt min/avg/max/mdev = 12.552/13.399/14.247/0.855 ms

        // FreeBSD : round-trip min/avg/max/stddev = 0.301/0.371/0.442/0.071 ms

        private static final Pattern PING_STATS_PATTERN = Pattern

                .compile("^\\p{Blank}*(?:rtt|round-trip)\\p{Blank}+min/avg/max/(?:mdev|stddev)\\p{Blank}+=\\p{Blank}+([0-9\\.]+)/([0-9\\.]+)/([0-9\\.]+)/([0-9\\.]+)\\p{Blank}+ms$");

        @Override

        protected BigDecimal parsePingAverageRT(String statsLine) {

            final Matcher m = PING_STATS_PATTERN.matcher(statsLine);

            if (!m.matches())

                throw new IllegalArgumentException("Not matching " + PING_STATS_PATTERN + " :\n" + statsLine);

            return new BigDecimal(m.group(2));

        }

        @Override

        public boolean isAdmin() throws IOException {

            // root is uid 0

            return cmdSubstitution(this.eval("id -u")).trim().equals("0");

        }

    }

    private static final Platform LINUX = new UnixPlatform() {

        @Override

        protected String getSelfProcessSymlink() {

            return "/proc/self";

        }

        @Override

        public PingResult ping(final InetAddress host, final PingBuilder pingBuilder, final int routingTableIndex) throws IOException {

            if (routingTableIndex > 0)

                throw new UnsupportedOperationException("On Linux, choosing a different routing table requires changing the system policy");

            final List<String> command = new ArrayList<String>(16);

            command.add("ping");

            final int totalCount = pingBuilder.getTotalCount();

            command.add("-c");

            command.add(String.valueOf(totalCount));

            if (pingBuilder.getWaitTime() > 0) {

                command.add("-W");

                final int timeInSeconds = pingBuilder.getWaitTime() / 1000;

                command.add(String.valueOf(Math.max(timeInSeconds, 1)));

            }

            command.add("-M");

            command.add(pingBuilder.isDontFragment() ? "do" : "dont");

            if (pingBuilder.getLength() > 0) {

                command.add("-s");

                command.add(String.valueOf(pingBuilder.getLength()));

            }

            if (pingBuilder.getTTL() > 0) {

                command.add("-t");

                command.add(String.valueOf(pingBuilder.getTTL()));

            }

            if (pingBuilder.getSourceAddress() != null) {

                command.add("-I");

                command.add(pingBuilder.getSourceAddress());

            }

            command.add(host.getHostAddress());

            return ping("out=$(" + CollectionUtils.join(command, " ") + ") ; grep -c ttl= <<< \"$out\" ; tail -n1 <<< \"$out\"", totalCount, pingBuilder.getRequiredReplies());

        }

    };

    private static final Platform FREEBSD = new UnixPlatform() {

        @Override

        protected String getSelfProcessSymlink() {

            return "/proc/curproc";

        }

        @Override

        public PingResult ping(final InetAddress host, final PingBuilder pingBuilder, final int routingTableIndex) throws IOException {

            final List<String> command = new ArrayList<String>(16);

            command.add("setfib");

            command.add(String.valueOf(routingTableIndex));

            command.add("ping");

            final int totalCount = pingBuilder.getTotalCount();

            command.add("-c");

            command.add(String.valueOf(totalCount));

            if (pingBuilder.getWaitTime() > 0) {

                command.add("-W");

                command.add(String.valueOf(pingBuilder.getWaitTime()));

            }

            if (pingBuilder.isDontFragment()) {

                command.add("-D");

            }

            if (pingBuilder.getLength() > 0) {

                command.add("-s");

                command.add(String.valueOf(pingBuilder.getLength()));

            }

            if (pingBuilder.getTTL() > 0) {

                command.add("-m");

                command.add(String.valueOf(pingBuilder.getTTL()));

            }

            if (pingBuilder.getSourceAddress() != null) {

                command.add("-S");

                command.add(pingBuilder.getSourceAddress());

            }

            command.add(host.getHostAddress());

            return ping("out=$(" + CollectionUtils.join(command, " ") + ") ; grep -c ttl= <<< \"$out\" ; tail -n1 <<< \"$out\"", totalCount, pingBuilder.getRequiredReplies());

        }

    };

    private static final Platform MACOS = new UnixPlatform() {

        @Override

        protected String getSelfProcessSymlink() {

            return null;

        }

        @Override

        protected PingResult ping(InetAddress host, PingBuilder pingBuilder, int routingTableIndex) throws IOException {

            return FREEBSD.ping(host, pingBuilder, routingTableIndex);

        }

    };

    // return 171 for "1.8.0_171"

    // return 11 for "11.0.11"

    public static final int getUpdateVersion(final char sep) {

        final String vers = System.getProperty("java.version");

        final int lastIndexOf = vers.lastIndexOf(sep);

        // e.g. "13"

        if (lastIndexOf < 0)

            return 0;

        return Integer.parseInt(vers.substring(lastIndexOf + 1));

    }

    public static abstract class WindowsPlatform extends Platform {

        // on Windows program themselves are required to parse the command line, thus a lot of them

        // do it differently, see "How Command Line Parameters Are Parsed"

        // https://daviddeley.com/autohotkey/parameters/parameters.htm

        static private final Pattern quotePatrn = Pattern.compile("([\\\\]*)\"");

        static private final Pattern endSlashPatrn = Pattern.compile("([\\\\]+)\\z");

        static private boolean needsQuoting(String s) {

            final int len = s.length();

            if (len == 0) // empty string have to be quoted

                return true;

            for (int i = 0; i < len; i++) {

                switch (s.charAt(i)) {

                case ' ':

                case '\t':

                case '"':

                    return true;

                }

            }

            return false;

        }

        // see http://bugs.sun.com/view_bug.do?bug_id=6468220

        // e.g. find.exe, choice.exe

        public String quoteParamForMsftC(String s) {

            if (!needsQuoting(s))

                return s;

            if (s.length() > 0) {

                // replace '(\*)"' by '$1$1\"', e.g. '\quote " \"' by '\quote \" \\\"'

                // $1 needed so that the backslash we add isn't escaped itself by a preceding

                // backslash

                s = quotePatrn.matcher(s).replaceAll("$1$1\\\\\"");

                // replace '(\*)\z' by '$1$1', e.g. 'foo\' by 'foo\\'

                // needed to not escape closing quote

                s = endSlashPatrn.matcher(s).replaceAll("$1$1");

            }

            return '"' + s + '"';

        }

        @Override

        public String getProcessArg(String arg) {

            return this.getProcessArg(arg, false);

        }

        public final String getScriptProcessArg(String arg) {

            return this.getProcessArg(arg, true);

        }

        private String getProcessArg(String arg, final boolean script) {

            // Perhaps should have one method for .exe and one for .cmd/.bat (ProcessImpl checks

            // with isShellFile() and isExe()).

            if (script && arg.indexOf('"') >= 0)

                throw new CannotPassArgumentException(arg, ", it contains a double quote which is always removed by wscript!SplitCommandLine()");

            /*

             * If has VERIFICATION_WIN32_SAFE && !allowAmbiguousCommands, then ProcessImpl behaves

             * almost correctly : the argument we pass arrives as-is to the process (so the caller

             * shouldn't quote, ProcessImpl will fail with "Malformed argument has embedded quote"

             * if a character was escaped). Otherwise ProcessImpl does nothing if arg begins and

             * ends with double quotes (it's the caller responsibility to correctly quote).

             */

            final boolean doubleQuote;

            // 1.8 or 11

            final String specVers = System.getProperty("java.specification.version");

            // 8 or 11

            final int jreFamilyVersion = Integer.parseInt(specVers.startsWith("1.") ? specVers.substring(2) : specVers);

            final String javaVendor = System.getProperty("java.vendor");

            // VERIFICATION_WIN32_SAFE thanks to https://nvd.nist.gov/vuln/detail/CVE-2019-2958

            // For Oracle and OpenJDK :

            // https://www.oracle.com/java/technologies/javase/8u231-relnotes.html#JDK-8221858

            // https://github.com/openjdk/jdk/commit/5a98b8cfb0cd4c5ce84746e9fa5e42a86d1b2d24#diff-71e1dde85b2937bbf08d0bfd9e8a2e3553c578a3f58907ba6f4f30ec350db184

            // For AdoptOpenJDK :

            // https://github.com/AdoptOpenJDK/openjdk-jdk11u/commit/0074850a15405a676a492d09e4955d4053966bbc#diff-71e1dde85b2937bbf08d0bfd9e8a2e3553c578a3f58907ba6f4f30ec350db184

            if (jreFamilyVersion >= 14 || (javaVendor.equals("AdoptOpenJDK") && (jreFamilyVersion == 11 && getUpdateVersion('.') >= 5 || jreFamilyVersion == 13 && getUpdateVersion('.') >= 1))

                    || (jreFamilyVersion == 8 && getUpdateVersion('_') >= 231)) {

                // copied from ProcessImpl

                final SecurityManager security = System.getSecurityManager();

                final String value = System.getProperty(PROCESS_ALLOW_AMBIGUOUS_COMMANDS, (security == null ? "true" : "false"));

                final boolean allowAmbiguousCommands = !"false".equalsIgnoreCase(value);

                if ((script || allowAmbiguousCommands) && arg.endsWith("\\")) {

                    // with script, we always do our own quoting since ProcessBuilder will double

                    // back slashes.

                    if (script || needsQuoting(arg)) {

                        throw new CannotPassArgumentException(arg,

                                ", if we'd double quote, then the string would end with 2 back slashes and 1 double quote, but ProcessImpl.unQuote() : 'not properly quoted, treat as unquoted'. So it would get quoted a second time. Try setting '"

                                        + PROCESS_ALLOW_AMBIGUOUS_COMMANDS + "' to 'false'.");

                    } else {

                        doubleQuote = false;

                    }

                } else if (!allowAmbiguousCommands && arg.length() >= 2 && arg.charAt(0) == '"' && arg.charAt(arg.length() - 1) == '"') {

                    throw new CannotPassArgumentException(arg,

                            "\nif we pass it as-is then ProcessImpl will consider the string already quoted and needsEscaping() will return false, thus the quotes will be removed by CommandLineToArgvW()"

                                    + "\nif we quote it then ProcessImpl.needsEscaping() will throw 'Malformed argument has embedded quote'");

                } else {

                    doubleQuote = allowAmbiguousCommands;

                }

            } else {

                doubleQuote = true;

            }

            if (script)

                return '"' + arg + '"';

            else

                return doubleQuote ? quoteParamForMsftC(arg) : arg;

        }

    }

    private static final class CygwinPlatform extends WindowsPlatform {

        @Override

        public boolean supportsPID() {

            return false;

        }

        @Override

        public boolean isRunning(int pid) throws IOException {

            // PID TTY STIME COMMAND

            // 864 ? 09:27:57 \??\C:\WINDOWS\system32\winlogon.exe

            // so if we count lines, we should get 2

            final Process p = this.eval("export PATH=$PATH:/usr/bin ; test $(ps -sW -p " + pid + " | wc -l) -eq 2 ");

            return this.exitStatus(p) == 0;

        }

        @Override

        protected String getBash() {

            // We used to specify the full path here, but this needed to be configurable (e.g.

            // cygwin 32 or 64 bit), plus all other programs are required to be on the PATH

            return "bash.exe";

        }

        @Override

        public String readLink(File f) throws IOException {

            // windows format to be able to use File

            final Process p = Runtime.getRuntime().exec(new String[] { "readshortcut.exe", "-w", f.getAbsolutePath() });

            return cmdSubstitution(p).trim();

        }

        @Override

        public String getPath(File f) {

            return toCygwinPath(f);

        }

        @Override

        public boolean ping(InetAddress host, final int timeout) throws IOException {

            // windows implem of isReachable() is buggy

            // see http://bordet.blogspot.com/2006/07/icmp-and-inetaddressisreachable.html

            final int exit = this.exitStatus(Runtime.getRuntime().exec("ping -n 1 -w " + timeout + " " + host.getHostAddress()), "ping");

            return exit == 0;

        }

        @Override

        public PingResult ping(final InetAddress host, final PingBuilder pingBuilder, final int routingTableIndex) throws IOException {

            if (routingTableIndex > 0)

                throw new UnsupportedOperationException("Only one routing table on Windows");

            final List<String> command = new ArrayList<String>(16);

            command.add("ping");

            final int totalCount = pingBuilder.getTotalCount();

            command.add("-n");

            command.add(String.valueOf(totalCount));

            if (pingBuilder.getWaitTime() > 0) {

                command.add("-w");

                command.add(String.valueOf(pingBuilder.getWaitTime()));

            }

            if (pingBuilder.isDontFragment()) {

                command.add("-f");

            }

            if (pingBuilder.getLength() > 0) {

                command.add("-l");

                command.add(String.valueOf(pingBuilder.getLength()));

            }

            if (pingBuilder.getTTL() > 0) {

                command.add("-i");

                command.add(String.valueOf(pingBuilder.getTTL()));

            }

            if (pingBuilder.getSourceAddress() != null) {

                command.add("-S");

                command.add(pingBuilder.getSourceAddress());

            }

            command.add(host.getHostAddress());

            // can't use local variable : never could work out newlines problem

            // see https://cygwin.com/ml/cygwin-announce/2011-02/msg00027.html

            return ping("tmpF=$(mktemp) && " + CollectionUtils.join(command, " ") + " > $tmpF ; grep -c \"TTL=\" < $tmpF ; tail -n1 $tmpF; rm \"$tmpF\"", totalCount, pingBuilder.getRequiredReplies());

        }

        // Minimum = 35ms, Maximum = 36ms, Moyenne = 35ms

        private static final Pattern PING_STATS_PATTERN = Pattern.compile("^\\p{Blank}*\\p{Alpha}+ = ([0-9\\.]+)ms, \\p{Alpha}+ = ([0-9\\.]+)ms, \\p{Alpha}+ = ([0-9\\.]+)ms$");

        @Override

        protected BigDecimal parsePingAverageRT(String statsLine) {

            final Matcher m = PING_STATS_PATTERN.matcher(statsLine);

            if (!m.matches())

                throw new IllegalArgumentException("Not matching " + PING_STATS_PATTERN + " : " + statsLine);

            return new BigDecimal(m.group(3));

        }

        @Override

        public boolean isAdmin() throws IOException {

            // SID administrators S-1-5-32-544 or S-1-5-114

            return this.exitStatus(this.eval("id -G | egrep '\\b(544|114)\\b'")) == 0;

        }

        @Override

        public boolean isSymLink(File f) throws IOException {

            // links created with "ln" can loose their "test -L" status over a copy (eg between two

            // Eclipse workspaces), so check with filename

            return getNativeSymlinkFile(f).exists() || super.isSymLink(f);

        }

        // when cygwin does "ln -s f link" it actually creates "link.lnk"

        @Override

        public File getNativeSymlinkFile(File dir) {

            return FileUtils.addSuffix(dir, ".lnk");

        }

    };

    private static final Platform CYGWIN = new CygwinPlatform();

    public static String toCygwinPath(File dir) {

        final List<File> ancestors = getAncestors(dir);

        final String root = ancestors.get(0).getPath();

        final List<File> rest = ancestors.subList(1, ancestors.size());

        return "/cygdrive/" + root.charAt(0) + "/" + CollectionUtils.join(rest, "/", new ITransformer<File, String>() {

            @Override

            public String transformChecked(File f) {

                return f.getName();

            }

        });

    }

    public static List<File> getAncestors(File f) {

        final File abs = f.getAbsoluteFile();

        File current = abs;

        final List<File> res = new ArrayList<File>();

        while (current != null) {

            res.add(0, current);

            current = current.getParentFile();

        }

        return res;

    }

    public static final class PingResult {

        private final int wantedCount, repliesCount, requiredReplies;

        private final BigDecimal averageRTT;

        private PingResult(final int wantedCount, final int repliesCount, final int requiredReplies, final BigDecimal averageRTT) {

            this.wantedCount = wantedCount;

            this.repliesCount = repliesCount;

            this.requiredReplies = requiredReplies;

            this.averageRTT = averageRTT;

        }

        public final int getRepliesCount() {

            return this.repliesCount;

        }

        public final int getRequiredReplies() {

            return this.requiredReplies;

        }

        public final boolean hasRequiredReplies() {

            return this.hasEnoughReplies(this.getRequiredReplies());

        }

        public final boolean hasEnoughReplies(final int min) {

            return this.getRepliesCount() >= min;

        }

        public final BigDecimal getAverageRTT() {

            return this.averageRTT;

        }

        @Override

        public String toString() {

            return this.getClass().getSimpleName() + " " + this.getRepliesCount() + "/" + this.wantedCount + " reply(ies), average RTT : " + this.getAverageRTT() + " ms";

        }

    }

    public static final class PingBuilder {

        private final Platform platform;

        // in milliseconds

        private int waitTime = 4000;

        private boolean dontFragment = false;

        private int length = -1;

        private String srcAddr = null;

        private int ttl = -1;

        private int totalCount = 4;

        private int requiredReplies = -1;

        PingBuilder(final Platform p) {

            this.platform = p;

        }

        public final PingBuilder setWaitTime(final int waitTime) {

            this.waitTime = waitTime;

            return this;

        }

        public final int getWaitTime() {

            return this.waitTime;

        }

        public final boolean isDontFragment() {

            return this.dontFragment;

        }

        public final PingBuilder setDontFragment(boolean dontFragment) {

            this.dontFragment = dontFragment;

            return this;

        }

        public final int getLength() {

            return this.length;

        }

        public final PingBuilder setLength(int length) {

            this.length = length;

            return this;

        }

        public String getSourceAddress() {

            return this.srcAddr;

        }

        public PingBuilder setSourceAddress(String srcAddr) {

            this.srcAddr = srcAddr;

            return this;

        }

        public final int getTTL() {

            return this.ttl;

        }

        public final PingBuilder setTTL(int ttl) {

            this.ttl = ttl;

            return this;

        }

        public final int getTotalCount() {

            return this.totalCount;

        }

        public final PingBuilder setTotalCount(int totalCount) {

            if (totalCount <= 0)

                throw new IllegalArgumentException("Negative count : " + totalCount);

            this.totalCount = totalCount;

            return this;

        }

        public final int getRequiredReplies() {

            return this.requiredReplies;

        }

        public final PingBuilder setRequiredReplies(int requiredReplies) {

            this.requiredReplies = requiredReplies;

            return this;

        }

        public final boolean isAlive(final InetAddress host) throws IOException {

            return this.isAlive(host, 0);

        }

        public final boolean isAlive(final InetAddress host, final int routingTableIndex) throws IOException {

            return execute(host, routingTableIndex).hasRequiredReplies();

        }

        public PingResult execute(final InetAddress host) throws IOException {

            return execute(host, 0);

        }

        public PingResult execute(final InetAddress host, final int routingTableIndex) throws IOException {

            return this.platform.ping(host, this, routingTableIndex);

        }

    }

    public static final class Ping {

        public static void main(String[] args) throws IOException {

            final int totalCount = Integer.parseInt(System.getProperty("count", "4"));

            final String srcAddr = System.getProperty("srcAddr");

            System.out.println(Platform.getInstance().createPingBuilder().setTotalCount(totalCount).setSourceAddress(srcAddr).execute(InetAddress.getByName(args[0])));

        }

    }

}