| /* |
| * 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 sun.tools.attach.HotSpotVirtualMachine; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.Random; |
| |
| public class VirtualMachineImpl extends HotSpotVirtualMachine { |
| |
| // the enqueue code stub (copied into each target VM) |
| private static byte[] stub; |
| |
| private volatile long hProcess; // handle to the process |
| |
| VirtualMachineImpl(AttachProvider provider, String id) |
| throws AttachNotSupportedException, IOException |
| { |
| super(provider, id); |
| |
| int pid; |
| try { |
| pid = Integer.parseInt(id); |
| } catch (NumberFormatException x) { |
| throw new AttachNotSupportedException("Invalid process identifier"); |
| } |
| hProcess = openProcess(pid); |
| |
| // The target VM might be a pre-6.0 VM so we enqueue a "null" command |
| // which minimally tests that the enqueue function exists in the target |
| // VM. |
| try { |
| enqueue(hProcess, stub, null, null); |
| } catch (IOException x) { |
| throw new AttachNotSupportedException(x.getMessage()); |
| } |
| } |
| |
| public void detach() throws IOException { |
| synchronized (this) { |
| if (hProcess != -1) { |
| closeProcess(hProcess); |
| hProcess = -1; |
| } |
| } |
| } |
| |
| InputStream execute(String cmd, Object ... args) |
| throws AgentLoadException, IOException |
| { |
| assert args.length <= 3; // includes null |
| |
| // create a pipe using a random name |
| int r = (new Random()).nextInt(); |
| String pipename = "\\\\.\\pipe\\javatool" + r; |
| long hPipe = createPipe(pipename); |
| |
| // check if we are detached - in theory it's possible that detach is invoked |
| // after this check but before we enqueue the command. |
| if (hProcess == -1) { |
| closePipe(hPipe); |
| throw new IOException("Detached from target VM"); |
| } |
| |
| try { |
| // enqueue the command to the process |
| enqueue(hProcess, stub, cmd, pipename, args); |
| |
| // wait for command to complete - process will connect with the |
| // completion status |
| connectPipe(hPipe); |
| |
| // create an input stream for the pipe |
| PipedInputStream in = new PipedInputStream(hPipe); |
| |
| // read completion status |
| int status = readInt(in); |
| if (status != 0) { |
| // read from the stream and use that as the error message |
| String message = readErrorMessage(in); |
| in.close(); |
| // special case the load command so that the right exception is thrown |
| if (cmd.equals("load")) { |
| String msg = "Failed to load agent library"; |
| if (!message.isEmpty()) |
| msg += ": " + message; |
| throw new AgentLoadException(msg); |
| } else { |
| if (message.isEmpty()) |
| message = "Command failed in target VM"; |
| throw new AttachOperationFailedException(message); |
| } |
| } |
| |
| // return the input stream |
| return in; |
| |
| } catch (IOException ioe) { |
| closePipe(hPipe); |
| throw ioe; |
| } |
| } |
| |
| // An InputStream based on a pipe to the target VM |
| private class PipedInputStream extends InputStream { |
| |
| private long hPipe; |
| |
| public PipedInputStream(long hPipe) { |
| this.hPipe = hPipe; |
| } |
| |
| 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 VirtualMachineImpl.readPipe(hPipe, bs, off, len); |
| } |
| |
| public void close() throws IOException { |
| if (hPipe != -1) { |
| VirtualMachineImpl.closePipe(hPipe); |
| hPipe = -1; |
| } |
| } |
| } |
| |
| |
| //-- native methods |
| |
| static native void init(); |
| |
| static native byte[] generateStub(); |
| |
| static native long openProcess(int pid) throws IOException; |
| |
| static native void closeProcess(long hProcess) throws IOException; |
| |
| static native long createPipe(String name) throws IOException; |
| |
| static native void closePipe(long hPipe) throws IOException; |
| |
| static native void connectPipe(long hPipe) throws IOException; |
| |
| static native int readPipe(long hPipe, byte buf[], int off, int buflen) throws IOException; |
| |
| static native void enqueue(long hProcess, byte[] stub, |
| String cmd, String pipename, Object ... args) throws IOException; |
| |
| static { |
| System.loadLibrary("attach"); |
| init(); // native initialization |
| stub = generateStub(); // generate stub to copy into target process |
| } |
| } |