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

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 * published by the Free Software Foundation.

 *

 * 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

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package sun.jvm.hotspot.debugger.windows.x86;

import sun.jvm.hotspot.debugger.*;

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

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

import sun.jvm.hotspot.debugger.cdbg.basic.*;

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

public class WindowsX86CFrame extends BasicCFrame {

  private Address ebp;

  private Address pc;

  private static final int ADDRESS_SIZE = 4;

  /** Constructor for topmost frame */

  public WindowsX86CFrame(WindbgDebugger dbg, Address ebp, Address pc) {

    super(dbg.getCDebugger());

    this.ebp = ebp;

    this.pc  = pc;

    this.dbg = dbg;

  }

  public CFrame sender(ThreadProxy thread) {

    X86ThreadContext context = (X86ThreadContext) thread.getContext();

    Address esp = context.getRegisterAsAddress(X86ThreadContext.ESP);

    if ( (ebp == null) || ebp.lessThan(esp) ) {

      return null;

    }

    // Check alignment of ebp

    if ( dbg.getAddressValue(ebp) % ADDRESS_SIZE != 0) {

        return null;

    }

    Address nextEBP = ebp.getAddressAt( 0 * ADDRESS_SIZE);

    if (nextEBP == null || nextEBP.lessThanOrEqual(ebp)) {

      return null;

    }

    Address nextPC  = ebp.getAddressAt( 1 * ADDRESS_SIZE);

    if (nextPC == null) {

      return null;

    }

    return new WindowsX86CFrame(dbg, nextEBP, nextPC);

  }

  public Address pc() {

    return pc;

  }

  public Address localVariableBase() {

    return ebp;

  }

  private WindbgDebugger dbg;

}