sun.tools.attach.SolarisVirtualMachine Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jmockit Show documentation
Show all versions of jmockit Show documentation
JMockit is a Java toolkit for automated developer testing.
It contains mocking/faking APIs and a code coverage tool, supporting both JUnit and TestNG.
The mocking APIs allow all kinds of Java code, without testability restrictions, to be tested
in isolation from selected dependencies.
/*
* Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.tools.attach;
import com.sun.tools.attach.AttachOperationFailedException;
import com.sun.tools.attach.AgentLoadException;
import com.sun.tools.attach.AttachNotSupportedException;
import com.sun.tools.attach.spi.AttachProvider;
import java.io.InputStream;
import java.io.IOException;
import java.io.File;
import java.io.FileNotFoundException;
/*
* Solaris implementation of HotSpotVirtualMachine.
*/
public class SolarisVirtualMachine extends HotSpotVirtualMachine {
// "/tmp" is used as a global well-known location for the files
// .java_pid. and .attach_pid. It is important that this
// location is the same for all processes, otherwise the tools
// will not be able to find all Hotspot processes.
// Any changes to this needs to be synchronized with HotSpot.
private static final String tmpdir = "/tmp";
// door descriptor;
private int fd = -1;
/**
* Attaches to the target VM
*/
public SolarisVirtualMachine(AttachProvider provider, String vmid)
throws AttachNotSupportedException, IOException
{
super(provider, vmid);
// This provider only understands process-ids (pids).
int pid;
try {
pid = Integer.parseInt(vmid);
} catch (NumberFormatException x) {
throw new AttachNotSupportedException("invalid process identifier");
}
// Opens the door file to the target VM. If the file is not
// found it might mean that the attach mechanism isn't started in the
// target VM so we attempt to start it and retry.
try {
fd = openDoor(pid);
} catch (FileNotFoundException fnf1) {
File f = createAttachFile(pid);
try {
// kill -QUIT will tickle target VM to check for the
// attach file.
sigquit(pid);
// give the target VM time to start the attach mechanism
int i = 0;
long delay = 200;
int retries = (int)(attachTimeout() / delay);
do {
try {
Thread.sleep(delay);
} catch (InterruptedException x) { }
try {
fd = openDoor(pid);
} catch (FileNotFoundException fnf2) { }
i++;
} while (i <= retries && fd == -1);
if (fd == -1) {
throw new AttachNotSupportedException(
"Unable to open door: target process not responding or " +
"HotSpot VM not loaded");
}
} finally {
f.delete();
}
}
assert fd >= 0;
}
/**
* Detach from the target VM
*/
public void detach() throws IOException {
synchronized (this) {
if (fd != -1) {
close(fd);
fd = -1;
}
}
}
/**
* Execute the given command in the target VM.
*/
InputStream execute(String cmd, Object ... args) throws AgentLoadException, IOException {
assert args.length <= 3; // includes null
// first check that we are still attached
int door;
synchronized (this) {
if (fd == -1) {
throw new IOException("Detached from target VM");
}
door = fd;
}
// enqueue the command via a door call
int s = enqueue(door, cmd, args);
assert s >= 0; // valid file descriptor
// The door call returns a file descriptor (one end of a socket pair).
// Create an input stream around it.
SocketInputStream sis = new SocketInputStream(s);
// Read the command completion status
int completionStatus;
try {
completionStatus = readInt(sis);
} catch (IOException ioe) {
sis.close();
throw ioe;
}
// If non-0 it means an error but we need to special-case the
// "load" command to ensure that the right exception is thrown.
if (completionStatus != 0) {
// read from the stream and use that as the error message
String message = readErrorMessage(sis);
sis.close();
if (cmd.equals("load")) {
throw new AgentLoadException("Failed to load agent library");
} else {
if (message == null) {
throw new AttachOperationFailedException("Command failed in target VM");
} else {
throw new AttachOperationFailedException(message);
}
}
}
// Return the input stream so that the command output can be read
return sis;
}
// InputStream over a socket
private class SocketInputStream extends InputStream {
int s;
public SocketInputStream(int s) {
this.s = s;
}
public synchronized int read() throws IOException {
byte b[] = new byte[1];
int n = this.read(b, 0, 1);
if (n == 1) {
return b[0] & 0xff;
} else {
return -1;
}
}
public synchronized int read(byte[] bs, int off, int len) throws IOException {
if ((off < 0) || (off > bs.length) || (len < 0) ||
((off + len) > bs.length) || ((off + len) < 0)) {
throw new IndexOutOfBoundsException();
} else if (len == 0)
return 0;
return SolarisVirtualMachine.read(s, bs, off, len);
}
public void close() throws IOException {
SolarisVirtualMachine.close(s);
}
}
// The door is attached to .java_pid in the temporary directory.
private int openDoor(int pid) throws IOException {
String path = tmpdir + "/.java_pid" + pid;;
fd = open(path);
// Check that the file owner/permission to avoid attaching to
// bogus process
try {
checkPermissions(path);
} catch (IOException ioe) {
close(fd);
throw ioe;
}
return fd;
}
// On Solaris/Linux a simple handshake is used to start the attach mechanism
// if not already started. The client creates a .attach_pid file in the
// target VM's working directory (or temporary directory), and the SIGQUIT
// handler checks for the file.
private File createAttachFile(int pid) throws IOException {
String fn = ".attach_pid" + pid;
String path = "/proc/" + pid + "/cwd/" + fn;
File f = new File(path);
try {
f.createNewFile();
} catch (IOException x) {
f = new File(tmpdir, fn);
f.createNewFile();
}
return f;
}
//-- native methods
static native int open(String path) throws IOException;
static native void close(int fd) throws IOException;
static native int read(int fd, byte buf[], int off, int buflen) throws IOException;
static native void checkPermissions(String path) throws IOException;
static native void sigquit(int pid) throws IOException;
// enqueue a command (and arguments) to the given door
static native int enqueue(int fd, String cmd, Object ... args)
throws IOException;
static {
System.loadLibrary("attach");
}
}