/*

 * 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.

 *

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

package sun.jvm.hotspot.utilities;

import sun.jvm.hotspot.code.*;

import sun.jvm.hotspot.debugger.*;

import sun.jvm.hotspot.gc_interface.*;

import sun.jvm.hotspot.interpreter.*;

import sun.jvm.hotspot.runtime.*;

import sun.jvm.hotspot.memory.*;

/** This class, only intended for use in the debugging system,

    provides the functionality of find() in the VM. */

public class PointerFinder {

  public static PointerLocation find(Address a) {

    PointerLocation loc = new PointerLocation(a);

    CollectedHeap heap = VM.getVM().getUniverse().heap();

    if (heap instanceof GenCollectedHeap) {

      GenCollectedHeap genheap = (GenCollectedHeap) heap;

      if (genheap.isIn(a)) {

        for (int i = 0; i < genheap.nGens(); i++) {

          Generation g = genheap.getGen(i);

          if (g.isIn(a)) {

            loc.gen = g;

            break;

          }

        }

        if (loc.gen == null) {

          // Should be in perm gen

          Generation permGen = genheap.permGen();

          if (Assert.ASSERTS_ENABLED) {

            Assert.that(permGen.isIn(a), "should have been in ordinary or perm gens if it's in the heap");

          }

          loc.permGen = permGen;

        }

        if (VM.getVM().getUseTLAB()) {

          // Try to find thread containing it

          for (JavaThread t = VM.getVM().getThreads().first(); t != null; t = t.next()) {

            ThreadLocalAllocBuffer tlab = t.tlab();

            if (tlab.contains(a)) {

              loc.inTLAB = true;

              loc.tlabThread = t;

              loc.tlab = tlab;

              break;

            }

          }

        }

        return loc;

      }

    } else {

      if (heap.isIn(a)) {

        loc.heap = heap;

        return loc;

      }

    }

    Interpreter interp = VM.getVM().getInterpreter();

    if (interp.contains(a)) {

      loc.inInterpreter = true;

      loc.interpreterCodelet = interp.getCodeletContaining(a);

      return loc;

    }

    if (!VM.getVM().isCore()) {

      CodeCache c = VM.getVM().getCodeCache();

      if (c.contains(a)) {

        loc.inCodeCache = true;

        loc.blob = c.findBlobUnsafe(a);

        if (Assert.ASSERTS_ENABLED) {

          Assert.that(loc.blob != null, "Should have found CodeBlob");

        }

        loc.inBlobInstructions = loc.blob.instructionsContains(a);

        loc.inBlobData         = loc.blob.dataContains(a);

        loc.inBlobUnknownLocation = (!(loc.inBlobInstructions ||

                                       loc.inBlobData ||

                                       loc.inBlobOops));

        return loc;

      }

    }

    // Check JNIHandles; both local and global

    JNIHandles handles = VM.getVM().getJNIHandles();

    JNIHandleBlock handleBlock = handles.globalHandles();

    if (handleBlock != null) {

      handleBlock = handleBlock.blockContainingHandle(a);

    }

    if (handleBlock != null) {

      loc.inStrongGlobalJNIHandleBlock = true;

      loc.handleBlock = handleBlock;

      return loc;

    } else {

      handleBlock = handles.weakGlobalHandles();

      if (handleBlock != null) {

        handleBlock = handleBlock.blockContainingHandle(a);

        if (handleBlock != null) {

          loc.inWeakGlobalJNIHandleBlock = true;

          loc.handleBlock = handleBlock;

          return loc;

        } else {

          // Look in thread-local handles

          for (JavaThread t = VM.getVM().getThreads().first(); t != null; t = t.next()) {

            handleBlock = t.activeHandles();

            if (handleBlock != null) {

              handleBlock = handleBlock.blockContainingHandle(a);

              if (handleBlock != null) {

                loc.inLocalJNIHandleBlock = true;

                loc.handleBlock = handleBlock;

                loc.handleThread = t;

                return loc;

              }

            }

          }

        }

      }

    }

    // Fall through; have to return it anyway.

    return loc;

  }

}