com.izforge.izpack.uninstaller.SelfModifier Maven / Gradle / Ivy
/*
* IzPack - Copyright 2001-2008 Julien Ponge, All Rights Reserved.
*
* http://izpack.org/
* http://izpack.codehaus.org/
*
* Copyright 2004 Chadwick McHenry
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.izforge.izpack.uninstaller;
import com.izforge.izpack.installer.MultiVolumeInstaller;
import com.izforge.izpack.util.OsVersion;
import java.io.*;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.net.URI;
import java.net.URL;
import java.text.CharacterIterator;
import java.text.SimpleDateFormat;
import java.text.StringCharacterIterator;
import java.util.Date;
import java.util.Enumeration;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.zip.ZipEntry;
/**
* Allows an application to modify the jar file from which it came, including outright deletion. The
* jar file of an app is usually locked when java is run so this is normally not possible.
*
*
* Create a SelfModifier with a target method, then invoke the SelfModifier with arguments to be
* passed to the target method. The jar file containing the target method's class (obtained by
* reflection) will be extracted to a temporary directory, and a new java process will be spawned to
* invoke the target method. The original jar file may now be modified.
*
*
* If the constructor or invoke() methods fail, it is generally because secondary java processes
* could not be started.
*
* Requirements
*
* - The target method, and all it's required classes must be in a jar file.
*
- The Self Modifier, and its inner classes must also be in the jar file.
*
*
* There are three system processes (or "phases") involved, the first invoked by the user, the
* second and third by the SelfModifier.
*
*
* Phase 1:
*
* - Program is launched, SelfModifier is created, invoke(String[]) is called
*
- A temporary directory (or "sandbox") is created in the default temp directory, and the jar
* file contents ar extracted into it
*
- Phase 2 is spawned using the sandbox as it's classpath, SelfModifier as the main class, the
* arguments to "invoke(String[])" as the main arguments, and the SelfModifier system properties set.
*
- Immidiately exit so the system unlocks the jar file
*
*
* Phase 2:
*
* - Initializes from system properties.
*
- Spawn phase 3 exactly as phase 2 except the self.modifier.phase system properties set to 3.
*
- Wait for phase 3 to die
*
- Delete the temporary sandbox
*
*
* Phase 3:
*
* - Initializes from system properties.
*
- Redirect std err stream to the log
*
- Invoke the target method with arguments we were given
*
- The target method is expected to call exit(), or to not start any looping threads (e.g. AWT
* thread). In other words, the target is the new "main" method.
*
*
* SelfModifier system properties used to pass information
* between processes.
*
* Constant
* System property
* description
*
* BASE_KEY
* self.mod.jar
* base path to log file and sandbox dir
*
* JAR_KEY
* self.mod.class
* path to original jar file
*
* CLASS_KEY
* self.mod.method
* class of target method
*
* METHOD_KEY
* self.mod.phase
* name of method to be invoked in sandbox
*
* PHASE_KEY
* self.mod.base
* phase of operation to run
*
*
* @author Chadwick McHenry
* @version 1.0
*/
public class SelfModifier
{
/**
* System property name of base for log and sandbox of secondary processes.
*/
public static final String BASE_KEY = "self.mod.base";
/**
* System property name of original jar file containing application.
*/
public static final String JAR_KEY = "self.mod.jar";
/**
* System property name of class declaring target method.
*/
public static final String CLASS_KEY = "self.mod.class";
/**
* System property name of target method to invoke in secondary process.
*/
public static final String METHOD_KEY = "self.mod.method";
/**
* System property name of phase (1, 2, or 3) indicator.
*/
public static final String PHASE_KEY = "self.mod.phase";
/**
* Base prefix name for sandbox and log, used only in phase 1.
*/
private String prefix = "izpack";
/**
* Target method to be invoked in sandbox.
*/
private Method method = null;
/**
* Log for phase 2 and 3, because we can't capture the stdio from them.
*/
private File logFile = null;
/**
* Directory which we extract too, invoke from, and finally delete.
*/
private File sandbox = null;
/**
* Original jar file program was launched from.
*/
private File jarFile = null;
/**
* Current phase of execution: 1, 2, or 3.
*/
private int phase = 0;
/**
* For logging time.
*/
private SimpleDateFormat isoPoint = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
private Date date = new Date();
public static void test(String[] args)
{
// open a File for random access in the sandbox, which will cause
// deletion
// of the file and its parent directories to fail until it is closed (by
// virtue of this java process halting)
try
{
File sandbox = new File(System.getProperty(BASE_KEY) + ".d");
File randFile = new File(sandbox, "RandomAccess.tmp");
RandomAccessFile rand = new RandomAccessFile(randFile, "rw");
rand.writeChars("Just a test: The jvm has to close 'cuz I won't!\n");
System.err.print("Deleting sandbox: ");
deleteTree(sandbox);
System.err.println(sandbox.exists() ? "FAILED" : "SUCCEEDED");
}
catch (Exception x)
{
System.err.println(x.getMessage());
x.printStackTrace();
}
}
public static void main(String[] args)
{
// phase 1 already set up the sandbox and spawned phase 2.
// phase 2 creates the log, spawns phase 3 and waits
// phase 3 invokes method and returns. method must kill all it's threads
try
{
// all it's attributes are retrieved from system properties
SelfModifier selfModifier = new SelfModifier();
// phase 2: invoke a process for phase 3, wait, and clean up
if (selfModifier.phase == 2)
{
selfModifier.invoke2(args);
}
// phase 3: invoke method and die
else if (selfModifier.phase == 3)
{
selfModifier.invoke3(args);
}
}
catch (IOException ioe)
{
System.err.println("Error invoking a secondary phase");
System.err.println("Note that this program is only intended as a secondary process");
ioe.printStackTrace();
}
}
/**
* Internal constructor where target class and method are obtained from system properties.
*
* @throws IOException for errors getting to the sandbox.
* @throws SecurityException if access to the target method is denied
*/
private SelfModifier() throws IOException
{
phase = Integer.parseInt(System.getProperty(PHASE_KEY));
String cName = System.getProperty(CLASS_KEY);
String tName = System.getProperty(METHOD_KEY);
jarFile = new File(System.getProperty(JAR_KEY));
logFile = new File(System.getProperty(BASE_KEY) + ".log");
sandbox = new File(System.getProperty(BASE_KEY) + ".d");
// retrieve refrence to target method
try
{
Class clazz = Class.forName(cName);
Method method = clazz.getMethod(tName, new Class[]{String[].class});
initMethod(method);
}
catch (ClassNotFoundException x1)
{
log("No class found for " + cName);
}
catch (NoSuchMethodException x2)
{
log("No method " + tName + " found in " + cName);
}
}
/**
* Creates a SelfModifier which will invoke the target method in a separate process from which
* it may modify it's own jar file.
*
* The target method must be public, static, and take a single array of strings as its only
* parameter. The class which declares the method must also be public. Reflection is used to
* ensure this.
*
* @param method a public, static method that accepts a String array as it's only parameter. Any
* return value is ignored.
* @throws NullPointerException if method is null
* @throws IllegalArgumentException if method is not public, static, and take a
* String array as it's only argument, or of it's declaring class is not public.
* @throws IllegalStateException if process was not invoked from a jar file, or an IOExceptioin
* occured while accessing it
* @throws IOException if java is unable to be executed as a separte process
* @throws SecurityException if access to the method, or creation of a subprocess is denied
*/
public SelfModifier(Method method) throws IOException
{
phase = 1;
initJavaExec();
initMethod(method);
}
/**
* Check the method for the required properties (public, static, params:(String[])).
*
* @throws NullPointerException if method is null
* @throws IllegalArgumentException if method is not public, static, and take a
* String array as it's only argument, or of it's declaring class is not public.
* @throws SecurityException if access to the method is denied
*/
private void initMethod(Method method)
{
int mod = method.getModifiers();
if ((mod & Modifier.PUBLIC) == 0 || (mod & Modifier.STATIC) == 0)
{
throw new IllegalArgumentException("Method not public and static");
}
Class[] params = method.getParameterTypes();
if (params.length != 1 || !params[0].isArray()
|| !"java.lang.String".equals(params[0].getComponentType().getName()))
{
throw new IllegalArgumentException("Method must accept String array");
}
Class clazz = method.getDeclaringClass();
mod = clazz.getModifiers();
if ((mod & Modifier.PUBLIC) == 0 || (mod & Modifier.INTERFACE) != 0)
{
throw new IllegalArgumentException("Method must be in a public class");
}
this.method = method;
}
/**
* This call ensures that java can be exec'd in a separate process.
*
* @throws IOException if an I/O error occurs, indicating java is unable to be exec'd
* @throws SecurityException if a security manager exists and doesn't allow creation of a
* subprocess
*/
private void initJavaExec() throws IOException
{
try
{
Process p = Runtime.getRuntime().exec(javaCommand());
new StreamProxy(p.getErrorStream(), "err").start();
new StreamProxy(p.getInputStream(), "out").start();
p.getOutputStream().close();
// even if it returns an error code, it was at least found
p.waitFor();
}
catch (InterruptedException ie)
{
throw new IOException("Unable to create a java subprocess");
}
}
/***********************************************************************************************
* --------------------------------------------------------------------- Phase 1 (call from
* external spawn phase 2) ---------------------------------------------------------------------
*/
/**
* Invoke the target method in a separate process from which it may modify it's own jar file.
* This method does not normally return. After spawning the secondary process, the current
* process must die before the jar file is unlocked, therefore calling this method is akin to
* calling {@link System#exit(int)}.
*
*
* The contents of the current jar file are extracted copied to a 'sandbox' directory from which
* the method is invoked. The path to the original jar file is placed in the system property
* {@link #JAR_KEY}.
*
*
* @param args arguments to pass to the target method. May be empty or null to indicate no
* arguments.
* @throws IOException for lots of things
* @throws IllegalStateException if method's class was not loaded from a jar
*/
public void invoke(String[] args) throws IOException
{
// Initialize sandbox and log file to be unique, but similarly named
while (true)
{
logFile = File.createTempFile(prefix, ".log");
String f = logFile.toString();
sandbox = new File(f.substring(0, f.length() - 4) + ".d");
// check if the similarly named directory is free
if (!sandbox.exists())
{
break;
}
logFile.delete();
}
if (!sandbox.mkdir())
{
throw new RuntimeException("Failed to create temp dir: " + sandbox);
}
sandbox = sandbox.getCanonicalFile();
logFile = logFile.getCanonicalFile();
jarFile = findJarFile((Class) method.getDeclaringClass()).getCanonicalFile();
if (jarFile == null)
{
throw new IllegalStateException("SelfModifier must be in a jar file");
}
log("JarFile: " + jarFile);
extractJarFile();
if (args == null)
{
args = new String[0];
}
spawn(args, 2);
// finally, if all went well, the invoking process must exit
log("Exit");
System.exit(0);
}
/**
* Run a new jvm with all the system parameters needed for phases 2 and 3.
*
* @throws IOException if there is an error getting the cononical name of a path
*/
private Process spawn(String[] args, int nextPhase) throws IOException
{
String base = logFile.getAbsolutePath();
base = base.substring(0, base.length() - 4);
// invoke from tmpdir, passing target method arguments as args, and
// SelfModifier parameters as sustem properties
String[] javaCmd = new String[]{javaCommand(), "-classpath", sandbox.getAbsolutePath(),
"-D" + BASE_KEY + "=" + base, "-D" + JAR_KEY + "=" + jarFile.getPath(),
"-D" + CLASS_KEY + "=" + method.getDeclaringClass().getName(),
"-D" + METHOD_KEY + "=" + method.getName(), "-D" + PHASE_KEY + "=" + nextPhase,
getClass().getName()};
String[] entireCmd = new String[javaCmd.length + args.length];
System.arraycopy(javaCmd, 0, entireCmd, 0, javaCmd.length);
System.arraycopy(args, 0, entireCmd, javaCmd.length, args.length);
StringBuffer sb = new StringBuffer("Spawning phase ");
sb.append(nextPhase).append(": ");
for (String anEntireCmd : entireCmd)
{
sb.append("\n\t").append(anEntireCmd);
}
log(sb.toString());
// Just invoke it and let it go, the exception will be caught above
// Won't compile on < jdk1.3, but will run on jre1.2
if (JAVA_SPECIFICATION_VERSION < 1.3)
{
return Runtime.getRuntime().exec(entireCmd, null);
}
else
{
return Runtime.getRuntime().exec(entireCmd, null, null); // workDir);
}
}
/**
* Retrieve the jar file the specified class was loaded from.
*
* @return null if file was not loaded from a jar file
* @throws SecurityException if access to is denied by SecurityManager
*/
public static File findJarFile(Class clazz)
{
String resource = clazz.getName().replace('.', '/') + ".class";
URL url = ClassLoader.getSystemResource(resource);
if (!"jar".equals(url.getProtocol()))
{
return null;
}
String path = url.getFile();
// starts at "file:..." (use getPath() as of 1.3)
path = path.substring(0, path.lastIndexOf('!'));
File file;
// getSystemResource() returns a valid URL (eg. spaces are %20), but a
// file
// Constructed w/ it will expect "%20" in path. URI and File(URI)
// properly
// deal with escaping back and forth, but didn't exist until 1.4
if (JAVA_SPECIFICATION_VERSION < 1.4)
{
file = new File(fromURI(path));
}
else
{
file = new File(URI.create(path));
}
return file;
}
/**
* @throws IOException
*/
private void extractJarFile() throws IOException
{
byte[] buf = new byte[5120];
int extracted = 0;
InputStream in = null;
OutputStream out = null;
String MANIFEST = "META-INF/MANIFEST.MF";
JarFile jar = new JarFile(jarFile, true);
try
{
Enumeration entries = jar.entries();
while (entries.hasMoreElements())
{
ZipEntry entry = entries.nextElement();
if (entry.isDirectory())
{
continue;
}
String pathname = entry.getName();
if (MANIFEST.equals(pathname.toUpperCase()))
{
continue;
}
in = jar.getInputStream(entry);
File outFile = new File(sandbox, pathname);
File parent = outFile.getParentFile();
if (parent != null && !parent.exists())
{
parent.mkdirs();
}
out = new BufferedOutputStream(new FileOutputStream(outFile));
int n;
while ((n = in.read(buf, 0, buf.length)) > 0)
{
out.write(buf, 0, n);
}
out.close();
extracted++;
}
jar.close();
log("Extracted " + extracted + " file" + (extracted > 1 ? "s" : "") + " into "
+ sandbox.getPath());
}
finally
{
try
{
jar.close();
}
catch (IOException ioe)
{
}
if (out != null)
{
try
{
out.close();
}
catch (IOException ioe)
{
}
}
if (in != null)
{
try
{
in.close();
}
catch (IOException ioe)
{
}
}
}
}
/***********************************************************************************************
* --------------------------------------------------------------------- Phase 2 (spawn the
* phase 3 and clean up) ---------------------------------------------------------------------
*/
/**
* Invoke phase 2, which starts phase 3, then cleans up the sandbox. This is needed because
* GUI's often call the exit() method to kill the AWT thread, and early versions of java did not
* have exit hooks. In order to delete the sandbox on exit we invoke method in separate process
* and wait for that process to complete. Even worse, resources in the jar may be locked by the
* target process, which would prevent the sandbox from being deleted as well.
*/
private void invoke2(String[] args)
{
int retVal = -1;
try
{
// TODO: in jre 1.2, Phs1 consistently needs more time to unlock the
// original jar. Phs2 should wait to invoke Phs3 until it knows its
// parent (Phs1) has died, but Process.waitFor() only works on
// children. Can we see when a parent dies, or /this/ Process
// becomes
// orphaned?
try
{
Thread.sleep(1000);
}
catch (Exception x)
{
}
// spawn phase 3, capture its stdio and wait for it to exit
Process p = spawn(args, 3);
new StreamProxy(p.getErrorStream(), "err", log).start();
new StreamProxy(p.getInputStream(), "out", log).start();
p.getOutputStream().close();
try
{
retVal = p.waitFor();
}
catch (InterruptedException e)
{
log(e);
}
// clean up and go
log("deleteing sandbox");
deleteTree(sandbox);
}
catch (Exception e)
{
log(e);
}
log("Phase 3 return value = " + retVal);
}
/**
* Recursively delete a file structure.
*/
public static boolean deleteTree(File file)
{
if (file.isDirectory())
{
File[] files = file.listFiles();
for (File file1 : files)
{
deleteTree(file1);
}
}
return file.delete();
}
/***********************************************************************************************
* --------------------------------------------------------------------- Phase 3 (invoke method,
* let it go as long as it likes)
* ---------------------------------------------------------------------
*/
/**
* Invoke the target method and let it run free!
*/
private void invoke3(String[] args)
{
// std io is being redirected to the log
try
{
errlog("Invoking method: " + method.getDeclaringClass().getName() + "."
+ method.getName() + "(String[] args)");
method.invoke(null, new Object[]{args});
}
catch (Throwable t)
{
errlog(t.getMessage());
t.printStackTrace();
errlog("exiting");
System.err.flush();
System.exit(31);
}
errlog("Method returned, waiting for other threads");
System.err.flush();
// now let the method call exit...
}
/**
* ********************************************************************************************
* --------------------------------------------------------------------- Logging
* ---------------------------------------------------------------------
*/
PrintStream log = null;
private void errlog(String msg)
{
date.setTime(System.currentTimeMillis());
System.err.println(isoPoint.format(date) + " Phase " + phase + ": " + msg);
}
private PrintStream checkLog()
{
try
{
if (log == null)
{
log = new PrintStream(new FileOutputStream(logFile.toString(), true));
}
}
catch (IOException x)
{
System.err.println("Phase " + phase + " log err: " + x.getMessage());
x.printStackTrace();
}
date.setTime(System.currentTimeMillis());
return log;
}
private void log(Throwable t)
{
if (checkLog() != null)
{
log.println(isoPoint.format(date) + " Phase " + phase + ": " + t.getMessage());
t.printStackTrace(log);
}
}
private void log(String msg)
{
if (checkLog() != null)
{
log.println(isoPoint.format(date) + " Phase " + phase + ": " + msg);
}
}
public static class StreamProxy extends Thread
{
InputStream in;
String name;
OutputStream out;
public StreamProxy(InputStream in, String name)
{
this(in, name, null);
}
public StreamProxy(InputStream in, String name, OutputStream out)
{
this.in = in;
this.name = name;
this.out = out;
}
public void run()
{
try
{
PrintWriter pw = null;
if (out != null)
{
pw = new PrintWriter(out);
}
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String line;
while ((line = br.readLine()) != null)
{
if (pw != null)
{
pw.println(line);
}
// System.out.println(name + ">" + line);
}
if (pw != null)
{
pw.flush();
}
}
catch (IOException ioe)
{
ioe.printStackTrace();
}
}
}
/**
* ********************************************************************************************
* --------------------------------------------------------------------- Apache ant code
* ---------------------------------------------------------------------
*/
// This was stolen (and specialized from much more modular code) from the
// jakarta ant class org.apache.tools.ant.taskdefs.condition.Os
// See the javaCommand() method.
private static final float JAVA_SPECIFICATION_VERSION = Float.parseFloat(System
.getProperty("java.specification.version"));
private static final String JAVA_HOME = System.getProperty("java.home");
/**
* Constructs a file path from a file: URI.
*
*
* Will be an absolute path if the given URI is absolute.
*
*
*
* Swallows '%' that are not followed by two characters, doesn't deal with non-ASCII characters.
*
*
* @param uri the URI designating a file in the local filesystem.
* @return the local file system path for the file.
*/
public static String fromURI(String uri)
{
if (!uri.startsWith("file:"))
{
throw new IllegalArgumentException("Can only handle file: URIs");
}
if (uri.startsWith("file://"))
{
uri = uri.substring(7);
}
else
{
uri = uri.substring(5);
}
uri = uri.replace('/', File.separatorChar);
if (File.pathSeparatorChar == ';' && uri.startsWith("\\") && uri.length() > 2
&& Character.isLetter(uri.charAt(1)) && uri.lastIndexOf(':') > -1)
{
uri = uri.substring(1);
}
StringBuffer sb = new StringBuffer();
CharacterIterator iter = new StringCharacterIterator(uri);
for (char c = iter.first(); c != CharacterIterator.DONE; c = iter.next())
{
if (c == '%')
{
char c1 = iter.next();
if (c1 != CharacterIterator.DONE)
{
int i1 = Character.digit(c1, 16);
char c2 = iter.next();
if (c2 != CharacterIterator.DONE)
{
int i2 = Character.digit(c2, 16);
sb.append((char) ((i1 << 4) + i2));
}
}
}
else
{
sb.append(c);
}
}
String path = sb.toString();
return path;
}
private static String addExtension(String command)
{
// This is the most common extension case - exe for windows and OS/2,
// nothing for *nix.
return command + (OsVersion.IS_WINDOWS || OsVersion.IS_OS2 ? ".exe" : "");
}
private static String javaCommand()
{
// This was stolen (and specialized from much more modular code) from
// the
// jakarta ant classes Os & JavaEnvUtils. Also see the following
// org.apache.tools.ant.taskdefs.Java
// org.apache.tools.ant.taskdefs.Execute
// org.apache.tools.ant.taskdefs.condition.Os
// org.apache.tools.ant.util.CommandlineJava
// org.apache.tools.ant.util.JavaEnvUtils
// org.apache.tools.ant.util.FileUtils
// TODO: I didn't copy nearly all of their conditions
String executable = addExtension("java");
String dir = new File(JAVA_HOME + "/bin").getAbsolutePath();
File jExecutable = new File(dir, executable);
// Unfortunately on Windows java.home doesn't always refer
// to the correct location, so we need to fall back to
// assuming java is somewhere on the PATH.
if (!jExecutable.exists())
{
return executable;
}
return jExecutable.getAbsolutePath();
}
}