/* -*- tab-width: 4 -*-
*
* Electric(tm) VLSI Design System
*
* File: ExecProcess.java
*
* Copyright (c) 2009 Sun Microsystems and Static Free Software
*
* Electric(tm) is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* Electric(tm) is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Electric(tm); see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, Mass 02111-1307, USA.
*/
package com.sun.electric.tool.io;
import java.net.*;
import java.util.*;
import java.io.*;
/**
* This class provides the same functionality as Runtime.exec(), but
* with extra safeguards and utilities. Includes the ability to
* execute a command on a remote machine via ssh, optionally rsync'ing
* the working directory to the remote machine before execution and
* back afterwards.
*
* This class should not depend on other Electric classes.
*
* @author megacz (heavily influenced by gainsley's ExecProcess)
*/
public class ExecProcess {
/** an OutputStream that discards anything written to it */
public static final OutputStream devNull = new OutputStream() {
public void write(int b) { }
public void write(byte[] b, int ofs, int len) { }
};
/** an InputStream that always returns EOF */
public static final InputStream eofInputStream = new InputStream() {
public int read() { return -1; }
public int read(byte[] buf, int ofs, int len) { return -1; }
public long skip(long ofs) { return 0; }
public int available() { return 0; }
};
/** any bytes written to this are written to all of its arguments */
public static class MultiOutputStream extends OutputStream {
private final OutputStream[] args;
public MultiOutputStream(OutputStream[] args) { this.args = args; }
public void write(int b) throws IOException { for(OutputStream os : args) os.write(b); }
public void write(byte[] b, int ofs, int len) throws IOException { for(OutputStream os : args) os.write(b,ofs,len); }
public void flush() throws IOException { for(OutputStream os : args) os.flush(); }
public void close() throws IOException { for(OutputStream os : args) os.close(); }
}
/**
* @param command the command to run (separated into argv[])
* @param workingDirectory the working directory on the LOCAL machine
*/
public ExecProcess(String[] command, File workingDirectory) {
this.command = command;
// Using java.io.tmpdir as the default working directory leads
// to far more predictable behavior than simply using the
// JVM's working directory. Electric already has a lot of
// bugs and quirks that result from doing that -- let's not
// add more!
if (workingDirectory==null)
workingDirectory = new File(System.getProperty("java.io.tmpdir"));
this.workingDirectory = workingDirectory;
}
/**
* @param host the hostname to run on
* @param user the username on the remote machine (or null to use
* whatever default ssh chooses)
* @param remoteWorkingDirectory the directory to work in on the remote machine
* @param syncBefore if true then "rsync --delete
* workingDirectory host:remoteWorkingDirectory" before
* invoking command.
* @param syncAfter if true and the command terminates with exit
* code zero, then "rsync --delete
* host:remoteWorkingDirectory workingDirectory" after
* invoking command.
*/
public synchronized void setRemote(String host, String user,
File remoteWorkingDirectory,
boolean syncBefore, boolean syncAfter) {
if (proc!=null) throw new RuntimeException("you cannot invoke ExecProcess.setRemote() after ExecProcess.start()");
throw new RuntimeException("not implemented");
}
/** undoes setRemote() */
public synchronized void setLocal() { }
public synchronized void redirectStdin(InputStream in) {
if (proc!=null) throw new RuntimeException("you cannot invoke ExecProcess.redirectStdin() after ExecProcess.start()");
this.redirectStdin = in;
}
public synchronized void redirectStdout(OutputStream os) {
if (proc!=null) throw new RuntimeException("you cannot invoke ExecProcess.redirectStdout() after ExecProcess.start()");
this.redirectStdout = os;
}
public synchronized void redirectStderr(OutputStream os) {
if (proc!=null) throw new RuntimeException("you cannot invoke ExecProcess.redirectStderr() after ExecProcess.start()");
this.redirectStderr = os;
}
public synchronized void start() throws IOException {
if (proc!=null) throw new RuntimeException("you cannot invoke ExecProcess.start() twice");
proc = Runtime.getRuntime().exec(command, null, workingDirectory);
if (redirectStdin != null) new StreamCopier(redirectStdin, proc.getOutputStream()).start();
if (redirectStdout != null) new StreamCopier(proc.getInputStream(), redirectStdout).start();
if (redirectStderr != null) new StreamCopier(proc.getErrorStream(), redirectStderr).start();
}
public synchronized void destroy() throws IOException {
if (proc==null) throw new RuntimeException("you must invoke ExecProcess.start() first");
proc.destroy();
}
public int waitFor() throws IOException {
if (proc==null) throw new RuntimeException("you must invoke ExecProcess.start() first");
try {
return proc.waitFor();
} catch (InterruptedException ie) {
throw new RuntimeException(ie);
}
}
public synchronized OutputStream getStdin() {
if (proc==null) throw new RuntimeException("you must invoke ExecProcess.start() first");
if (redirectStdin!=null) throw new RuntimeException("you cannot invoke getStdin() after redirectStdin()");
return proc.getOutputStream();
}
public synchronized InputStream getStdout() {
if (proc==null) throw new RuntimeException("you must invoke ExecProcess.start() first");
if (redirectStdout!=null) throw new RuntimeException("you cannot invoke getStdout() after redirectStdout()");
return proc.getInputStream();
}
public synchronized InputStream getStderr() {
if (proc==null) throw new RuntimeException("you must invoke ExecProcess.start() first");
if (redirectStderr!=null) throw new RuntimeException("you cannot invoke getStderr() after redirectStderr()");
return proc.getErrorStream();
}
private Process proc;
private InputStream redirectStdin;
private OutputStream redirectStdout;
private OutputStream redirectStderr;
private String[] command;
private File workingDirectory;
/**
* Copies from an InputStream to an OutputStream; used to implement redirectXXX().
*/
private static class StreamCopier extends Thread {
private final byte[] buf = new byte[16 * 1024];
private final InputStream is;
private final OutputStream os;
public StreamCopier(InputStream is, OutputStream os) {
setDaemon(true);
this.is = is;
this.os = os;
}
public void run() {
try {
while(true) {
int numread = is.read(buf, 0, buf.length);
if (numread==-1) break;
os.write(buf, 0, numread);
}
} catch (Exception e) { throw new RuntimeException(e); }
}
}
}