1 /*

     2  * Copyright (c) 2002, 2003, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    24 

    25 package sun.jvm.hotspot.runtime.linux_x86;

    26 

    27 import java.io.*;

    28 import java.util.*;

    29 import sun.jvm.hotspot.debugger.*;

    30 import sun.jvm.hotspot.debugger.x86.*;

    31 import sun.jvm.hotspot.runtime.*;

    32 import sun.jvm.hotspot.runtime.x86.*;

    33 import sun.jvm.hotspot.types.*;

    34 import sun.jvm.hotspot.utilities.*;

    35 

    36 public class LinuxX86JavaThreadPDAccess implements JavaThreadPDAccess {

    37   private static AddressField  lastJavaFPField;

    38   private static AddressField  osThreadField;

    39 

    40   // Field from OSThread

    41   private static CIntegerField osThreadThreadIDField;

    42 

    43   // This is currently unneeded but is being kept in case we change

    44   // the currentFrameGuess algorithm

    45   private static final long GUESS_SCAN_RANGE = 128 * 1024;

    46 

    47   static {

    48     VM.registerVMInitializedObserver(new Observer() {

    49         public void update(Observable o, Object data) {

    50           initialize(VM.getVM().getTypeDataBase());

    51         }

    52       });

    53   }

    54 

    55   private static synchronized void initialize(TypeDataBase db) {

    56     Type type = db.lookupType("JavaThread");

    57     osThreadField           = type.getAddressField("_osthread");

    58 

    59     Type anchorType = db.lookupType("JavaFrameAnchor");

    60     lastJavaFPField         = anchorType.getAddressField("_last_Java_fp");

    61 

    62     Type osThreadType = db.lookupType("OSThread");

    63     osThreadThreadIDField   = osThreadType.getCIntegerField("_thread_id");

    64   }

    65 

    66   public    Address getLastJavaFP(Address addr) {

    67     return lastJavaFPField.getValue(addr.addOffsetTo(sun.jvm.hotspot.runtime.JavaThread.getAnchorField().getOffset()));

    68   }

    69 

    70   public    Address getLastJavaPC(Address addr) {

    71     return null;

    72   }

    73 

    74   public    Address getBaseOfStackPointer(Address addr) {

    75     return null;

    76   }

    77 

    78   public    Frame getLastFramePD(JavaThread thread, Address addr) {

    79     Address fp = thread.getLastJavaFP();

    80     if (fp == null) {

    81       return null; // no information

    82     }

    83     return new X86Frame(thread.getLastJavaSP(), fp);

    84   }

    85 

    86   public    RegisterMap newRegisterMap(JavaThread thread, boolean updateMap) {

    87     return new X86RegisterMap(thread, updateMap);

    88   }

    89 

    90   public    Frame getCurrentFrameGuess(JavaThread thread, Address addr) {

    91     ThreadProxy t = getThreadProxy(addr);

    92     X86ThreadContext context = (X86ThreadContext) t.getContext();

    93     X86CurrentFrameGuess guesser = new X86CurrentFrameGuess(context, thread);

    94     if (!guesser.run(GUESS_SCAN_RANGE)) {

    95       return null;

    96     }

    97     if (guesser.getPC() == null) {

    98       return new X86Frame(guesser.getSP(), guesser.getFP());

    99     } else {

   100       return new X86Frame(guesser.getSP(), guesser.getFP(), guesser.getPC());

   101     }

   102   }

   103 

   104   public    void printThreadIDOn(Address addr, PrintStream tty) {

   105     tty.print(getThreadProxy(addr));

   106   }

   107 

   108   public    void printInfoOn(Address threadAddr, PrintStream tty) {

   109     tty.print("Thread id: ");

   110     printThreadIDOn(threadAddr, tty);

   111 //    tty.println("\nPostJavaState: " + getPostJavaState(threadAddr));

   112   }

   113 

   114   public    Address getLastSP(Address addr) {

   115     ThreadProxy t = getThreadProxy(addr);

   116     X86ThreadContext context = (X86ThreadContext) t.getContext();

   117     return context.getRegisterAsAddress(X86ThreadContext.ESP);

   118   }

   119 

   120   public    ThreadProxy getThreadProxy(Address addr) {

   121     // Addr is the address of the JavaThread.

   122     // Fetch the OSThread (for now and for simplicity, not making a

   123     // separate "OSThread" class in this package)

   124     Address osThreadAddr = osThreadField.getValue(addr);

   125     // Get the address of the _thread_id from the OSThread

   126     Address threadIdAddr = osThreadAddr.addOffsetTo(osThreadThreadIDField.getOffset());

   127 

   128     JVMDebugger debugger = VM.getVM().getDebugger();

   129     return debugger.getThreadForIdentifierAddress(threadIdAddr);

   130   }

   131 }