java/lang/UNIXProcess.java.solaris

	UNIXProcess.java.solaris revision 0
0N/A/*
1472N/A * Copyright 1995-2006 Sun Microsystems, Inc.  All Rights Reserved.
0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
0N/A *
0N/A * This code is free software; you can redistribute it and/or modify it
0N/A * under the terms of the GNU General Public License version 2 only, as
0N/A * published by the Free Software Foundation.  Sun designates this
0N/A * particular file as subject to the "Classpath" exception as provided
0N/A * by Sun in the LICENSE file that accompanied this code.
0N/A *
0N/A * This code is distributed in the hope that it will be useful, but WITHOUT
0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
0N/A * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
0N/A * version 2 for more details (a copy is included in the LICENSE file that
0N/A * accompanied this code).
0N/A *
0N/A * You should have received a copy of the GNU General Public License version
0N/A * 2 along with this work; if not, write to the Free Software Foundation,
1472N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1472N/A *
1472N/A * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
0N/A * CA 95054 USA or visit www.sun.com if you need additional information or
0N/A * have any questions.
0N/A */
0N/A
0N/Apackage java.lang;
0N/A
0N/Aimport java.io.*;
0N/A
0N/A/* java.lang.Process subclass in the UNIX environment.
0N/A *
0N/A * @author Mario Wolczko and Ross Knippel.
0N/A */
0N/A
0N/Afinal class UNIXProcess extends Process {
0N/A    private FileDescriptor stdin_fd;
0N/A    private FileDescriptor stdout_fd;
0N/A    private FileDescriptor stderr_fd;
0N/A    private int pid;
0N/A    private int exitcode;
0N/A    private boolean hasExited;
0N/A
0N/A    private OutputStream stdin_stream;
0N/A    private BufferedInputStream stdout_stream;
0N/A    private DeferredCloseInputStream stdout_inner_stream;
0N/A    private DeferredCloseInputStream stderr_stream;
0N/A
0N/A    /* this is for the reaping thread */
0N/A    private native int waitForProcessExit(int pid);
0N/A
0N/A    private native int forkAndExec(byte[] prog,
0N/A                   byte[] argBlock, int argc,
0N/A                   byte[] envBlock, int envc,
0N/A                   byte[] dir,
0N/A                   boolean redirectErrorStream,
0N/A                   FileDescriptor stdin_fd,
0N/A                   FileDescriptor stdout_fd,
0N/A                   FileDescriptor stderr_fd)
0N/A    throws IOException;
0N/A
0N/A    UNIXProcess(final byte[] prog,
0N/A        final byte[] argBlock, int argc,
0N/A        final byte[] envBlock, int envc,
0N/A        final byte[] dir,
0N/A        final boolean redirectErrorStream)
0N/A    throws IOException {
0N/A    stdin_fd  = new FileDescriptor();
0N/A    stdout_fd = new FileDescriptor();
0N/A    stderr_fd = new FileDescriptor();
0N/A
0N/A    pid = forkAndExec(prog,
0N/A              argBlock, argc,
0N/A              envBlock, envc,
0N/A              dir,
0N/A              redirectErrorStream,
0N/A              stdin_fd, stdout_fd, stderr_fd);
0N/A
0N/A    java.security.AccessController.doPrivileged(
0N/A                    new java.security.PrivilegedAction() {
0N/A        public Object run() {
0N/A            stdin_stream
0N/A            = new BufferedOutputStream(new FileOutputStream(stdin_fd));
0N/A        stdout_inner_stream = new DeferredCloseInputStream(stdout_fd);
0N/A            stdout_stream = new BufferedInputStream(stdout_inner_stream);
0N/A            stderr_stream = new DeferredCloseInputStream(stderr_fd);
0N/A        return null;
1010N/A        }
0N/A    });
113N/A
113N/A    /*
113N/A     * For each subprocess forked a corresponding reaper thread
0N/A     * is started.  That thread is the only thread which waits
1601N/A     * for the subprocess to terminate and it doesn't hold any
0N/A     * locks while doing so.  This design allows waitFor() and
0N/A     * exitStatus() to be safely executed in parallel (and they
0N/A     * need no native code).
1601N/A     */
1601N/A
1601N/A    java.security.AccessController.doPrivileged(
1601N/A                new java.security.PrivilegedAction() {
1601N/A        public Object run() {
0N/A        Thread t = new Thread("process reaper") {
0N/A            public void run() {
1010N/A            int res = waitForProcessExit(pid);
1010N/A            synchronized (UNIXProcess.this) {
1010N/A                hasExited = true;
1010N/A                exitcode = res;
1010N/A                UNIXProcess.this.notifyAll();
1010N/A            }
0N/A            }
0N/A        };
0N/A        t.setDaemon(true);
0N/A        t.start();
0N/A        return null;
0N/A        }
0N/A    });
0N/A    }
0N/A
0N/A    public OutputStream getOutputStream() {
0N/A    return stdin_stream;
0N/A    }
0N/A
0N/A    public InputStream getInputStream() {
0N/A    return stdout_stream;
0N/A    }
0N/A
0N/A    public InputStream getErrorStream() {
0N/A    return stderr_stream;
0N/A    }
0N/A
0N/A    public synchronized int waitFor() throws InterruptedException {
0N/A        while (!hasExited) {
0N/A        wait();
0N/A    }
0N/A    return exitcode;
1010N/A    }
1010N/A
1010N/A    public synchronized int exitValue() {
1010N/A    if (!hasExited) {
0N/A        throw new IllegalThreadStateException("process hasn't exited");
0N/A    }
0N/A    return exitcode;
0N/A    }
0N/A
0N/A    private static native void destroyProcess(int pid);
0N/A    public synchronized void destroy() {
0N/A    // There is a risk that pid will be recycled, causing us to
0N/A    // kill the wrong process!  So we only terminate processes
0N/A    // that appear to still be running.  Even with this check,
0N/A    // there is an unavoidable race condition here, but the window
0N/A    // is very small, and OSes try hard to not recycle pids too
0N/A    // soon, so this is quite safe.
0N/A    if (!hasExited)
0N/A        destroyProcess(pid);
0N/A    try {
0N/A            stdin_stream.close();
0N/A        stdout_inner_stream.closeDeferred(stdout_stream);
0N/A        stderr_stream.closeDeferred(stderr_stream);
0N/A        } catch (IOException e) {
0N/A            // ignore
0N/A        }
0N/A    }
0N/A
0N/A    // A FileInputStream that supports the deferment of the actual close
0N/A    // operation until the last pending I/O operation on the stream has
0N/A    // finished.  This is required on Solaris because we must close the stdin
0N/A    // and stdout streams in the destroy method in order to reclaim the
0N/A    // underlying file descriptors.  Doing so, however, causes any thread
0N/A    // currently blocked in a read on one of those streams to receive an
0N/A    // IOException("Bad file number"), which is incompatible with historical
0N/A    // behavior.  By deferring the close we allow any pending reads to see -1
0N/A    // (EOF) as they did before.
0N/A    //
0N/A    private static class DeferredCloseInputStream
0N/A    extends FileInputStream
0N/A    {
0N/A
0N/A    private DeferredCloseInputStream(FileDescriptor fd) {
0N/A        super(fd);
0N/A    }
0N/A
0N/A    private Object lock = new Object(); // For the following fields
0N/A    private boolean closePending = false;
0N/A    private int useCount = 0;
0N/A    private InputStream streamToClose;
0N/A
0N/A    private void raise() {
0N/A        synchronized (lock) {
0N/A        useCount++;
0N/A        }
0N/A    }
0N/A
0N/A    private void lower() throws IOException {
0N/A        synchronized (lock) {
0N/A        useCount--;
0N/A        if (useCount == 0 && closePending) {
0N/A            streamToClose.close();
0N/A        }
0N/A        }
1010N/A    }
1010N/A
1010N/A    // stc is the actual stream to be closed; it might be this object, or
1010N/A    // it might be an upstream object for which this object is downstream.
1010N/A    //
1010N/A    private void closeDeferred(InputStream stc) throws IOException {
0N/A        synchronized (lock) {
0N/A        if (useCount == 0) {
0N/A            stc.close();
0N/A        } else {
0N/A            closePending = true;
0N/A            streamToClose = stc;
0N/A        }
0N/A        }
0N/A    }
0N/A
0N/A    public void close() throws IOException {
0N/A        synchronized (lock) {
0N/A        useCount = 0;
0N/A        closePending = false;
0N/A        }
0N/A        super.close();
0N/A    }
0N/A
0N/A    public int read() throws IOException {
0N/A        raise();
0N/A        try {
0N/A        return super.read();
0N/A        } finally {
0N/A        lower();
0N/A        }
0N/A    }
0N/A
0N/A    public int read(byte[] b) throws IOException {
0N/A        raise();
0N/A        try {
1010N/A        return super.read(b);
0N/A        } finally {
0N/A        lower();
0N/A        }
1010N/A    }
0N/A
0N/A    public int read(byte[] b, int off, int len) throws IOException {
1010N/A        raise();
1010N/A        try {
1010N/A        return super.read(b, off, len);
1010N/A        } finally {
0N/A        lower();
0N/A        }
0N/A    }
0N/A
0N/A    public long skip(long n) throws IOException {
0N/A        raise();
0N/A        try {
1010N/A        return super.skip(n);
0N/A        } finally {
0N/A        lower();
0N/A        }
0N/A    }
0N/A
0N/A    public int available() throws IOException {
0N/A        raise();
0N/A        try {
0N/A        return super.available();
0N/A        } finally {
0N/A        lower();
0N/A        }
0N/A    }
0N/A
0N/A    }
0N/A
0N/A    /* This routine initializes JNI field offsets for the class */
0N/A    private static native void initIDs();
0N/A
0N/A    static {
0N/A    initIDs();
0N/A    }
0N/A}
0N/A