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JMockit is a Java toolkit for developer (unit/integration) testing.
It contains mocking APIs and other tools, 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, 2012, 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.
*
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package sun.tools.attach;
import com.sun.tools.attach.VirtualMachine;
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.util.Properties;
/*
* Bsd implementation of HotSpotVirtualMachine
*/
public class BsdVirtualMachine extends HotSpotVirtualMachine {
// "tmpdir" 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.
// This is intentionally not the same as java.io.tmpdir, since
// the latter can be changed by the user.
// Any changes to this needs to be synchronized with HotSpot.
private static final String tmpdir;
// The patch to the socket file created by the target VM
String path;
/**
* Attaches to the target VM
*/
public BsdVirtualMachine(AttachProvider provider, String vmid)
throws AttachNotSupportedException, IOException
{
super(provider, vmid);
// This provider only understands pids
int pid;
try {
pid = Integer.parseInt(vmid);
} catch (NumberFormatException x) {
throw new AttachNotSupportedException("Invalid process identifier");
}
// Find the socket file. If not found then we attempt to start the
// attach mechanism in the target VM by sending it a QUIT signal.
// Then we attempt to find the socket file again.
path = findSocketFile(pid);
if (path == null) {
File f = new File(tmpdir, ".attach_pid" + pid);
createAttachFile(f.getPath());
try {
sendQuitTo(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) { }
path = findSocketFile(pid);
i++;
} while (i <= retries && path == null);
if (path == null) {
throw new AttachNotSupportedException(
"Unable to open socket file: target process not responding " +
"or HotSpot VM not loaded");
}
} finally {
f.delete();
}
}
// Check that the file owner/permission to avoid attaching to
// bogus process
checkPermissions(path);
// Check that we can connect to the process
// - this ensures we throw the permission denied error now rather than
// later when we attempt to enqueue a command.
int s = socket();
try {
connect(s, path);
} finally {
close(s);
}
}
/**
* Detach from the target VM
*/
public void detach() throws IOException {
synchronized (this) {
if (this.path != null) {
this.path = null;
}
}
}
// protocol version
private final static String PROTOCOL_VERSION = "1";
// known errors
private final static int ATTACH_ERROR_BADVERSION = 101;
/**
* Execute the given command in the target VM.
*/
InputStream execute(String cmd, Object ... args) throws AgentLoadException, IOException {
assert args.length <= 3; // includes null
// did we detach?
String p;
synchronized (this) {
if (this.path == null) {
throw new IOException("Detached from target VM");
}
p = this.path;
}
// create UNIX socket
int s = socket();
// connect to target VM
try {
connect(s, p);
} catch (IOException x) {
close(s);
throw x;
}
IOException ioe = null;
// connected - write request
//
try {
writeString(s, PROTOCOL_VERSION);
writeString(s, cmd);
for (int i=0; i<3; i++) {
if (i < args.length && args[i] != null) {
writeString(s, (String)args[i]);
} else {
writeString(s, "");
}
}
} catch (IOException x) {
ioe = x;
}
// Create an input stream to read reply
SocketInputStream sis = new SocketInputStream(s);
// Read the command completion status
int completionStatus;
try {
completionStatus = readInt(sis);
} catch (IOException x) {
sis.close();
if (ioe != null) {
throw ioe;
} else {
throw x;
}
}
if (completionStatus != 0) {
sis.close();
// In the event of a protocol mismatch then the target VM
// returns a known error so that we can throw a reasonable
// error.
if (completionStatus == ATTACH_ERROR_BADVERSION) {
throw new IOException("Protocol mismatch with target VM");
}
// Special-case the "load" command so that the right exception is
// thrown.
if (cmd.equals("load")) {
throw new AgentLoadException("Failed to load agent library");
} else {
throw new IOException("Command failed in target VM");
}
}
// Return the input stream so that the command output can be read
return sis;
}
/*
* InputStream for the socket connection to get target VM
*/
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 BsdVirtualMachine.read(s, bs, off, len);
}
public void close() throws IOException {
BsdVirtualMachine.close(s);
}
}
// Return the socket file for the given process.
// Checks temp directory for .java_pid.
private String findSocketFile(int pid) {
String fn = ".java_pid" + pid;
File f = new File(tmpdir, fn);
return f.exists() ? f.getPath() : null;
}
/*
* Write/sends the given to the target VM. String is transmitted in
* UTF-8 encoding.
*/
private void writeString(int fd, String s) throws IOException {
if (s.length() > 0) {
byte b[];
try {
b = s.getBytes("UTF-8");
} catch (java.io.UnsupportedEncodingException x) {
throw new InternalError();
}
BsdVirtualMachine.write(fd, b, 0, b.length);
}
byte b[] = new byte[1];
b[0] = 0;
write(fd, b, 0, 1);
}
//-- native methods
static native void sendQuitTo(int pid) throws IOException;
static native void checkPermissions(String path) throws IOException;
static native int socket() throws IOException;
static native void connect(int fd, 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 write(int fd, byte buf[], int off, int bufLen) throws IOException;
static native void createAttachFile(String path);
static native String getTempDir();
static {
System.loadLibrary("attach");
tmpdir = getTempDir();
}
}