/*

 * Copyright (c) 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.

 *

 * 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.

 *

 */

#ifndef SHARE_VM_MEMORY_METASPACE_SHARED_HPP

#define SHARE_VM_MEMORY_METASPACE_SHARED_HPP

#include "memory/allocation.hpp"

#include "memory/memRegion.hpp"

#include "runtime/virtualspace.hpp"

#include "utilities/exceptions.hpp"

#include "utilities/macros.hpp"

class FileMapInfo;

// Class Data Sharing Support

class MetaspaceShared : AllStatic {

  // CDS support

  static ReservedSpace* _shared_rs;

  static int _max_alignment;

 public:

  enum {

    vtbl_list_size = 17, // number of entries in the shared space vtable list.

    num_virtuals = 200   // maximum number of virtual functions

                         // If virtual functions are added to Metadata,

                         // this number needs to be increased.  Also,

                         // SharedMiscCodeSize will need to be increased.

  };

  enum {

    ro = 0,  // read-only shared space in the heap

    rw = 1,  // read-write shared space in the heap

    md = 2,  // miscellaneous data for initializing tables, etc.

    mc = 3,  // miscellaneous code - vtable replacement.

    n_regions = 4

  };

  // Accessor functions to save shared space created for metadata, which has

  // extra space allocated at the end for miscellaneous data and code.

  static void set_max_alignment(int alignment) {

    CDS_ONLY(_max_alignment = alignment);

  }

  static int max_alignment() {

    CDS_ONLY(return _max_alignment);

    NOT_CDS(return 0);

  }

  static void preload_and_dump(TRAPS) NOT_CDS_RETURN;

  static ReservedSpace* shared_rs() {

    CDS_ONLY(return _shared_rs);

    NOT_CDS(return NULL);

  }

  static void set_shared_rs(ReservedSpace* rs) {

    CDS_ONLY(_shared_rs = rs;)

  }

  static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);

  static void initialize_shared_spaces() NOT_CDS_RETURN;

  // Return true if given address is in the mapped shared space.

  static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false);

  static void generate_vtable_methods(void** vtbl_list,

                                      void** vtable,

                                      char** md_top, char* md_end,

                                      char** mc_top, char* mc_end);

  static void serialize(SerializeClosure* sc);

  // JVM/TI RedefineClasses() support:

  // Remap the shared readonly space to shared readwrite, private if

  // sharing is enabled. Simply returns true if sharing is not enabled

  // or if the remapping has already been done by a prior call.

  static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);

  static void print_shared_spaces();

};

#endif // SHARE_VM_MEMORY_METASPACE_SHARED_HPP