/*

 * Copyright (c) 2003, 2017, 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_CLASSFILE_LOADERCONSTRAINTS_HPP

#define SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP

#include "classfile/dictionary.hpp"

#include "classfile/placeholders.hpp"

#include "utilities/hashtable.hpp"

class LoaderConstraintEntry;

class Symbol;

class LoaderConstraintTable : public Hashtable<InstanceKlass*, mtClass> {

  friend class VMStructs;

private:

  enum Constants {

    _loader_constraint_size = 107,                     // number of entries in constraint table

    _nof_buckets            = 1009                     // number of buckets in hash table

  };

  LoaderConstraintEntry** find_loader_constraint(Symbol* name,

                                                 Handle loader);

public:

  LoaderConstraintTable(int nof_buckets);

  LoaderConstraintEntry* new_entry(unsigned int hash, Symbol* name,

                                   InstanceKlass* klass, int num_loaders,

                                   int max_loaders);

  void free_entry(LoaderConstraintEntry *entry);

  LoaderConstraintEntry* bucket(int i) {

    return (LoaderConstraintEntry*)Hashtable<InstanceKlass*, mtClass>::bucket(i);

  }

  LoaderConstraintEntry** bucket_addr(int i) {

    return (LoaderConstraintEntry**)Hashtable<InstanceKlass*, mtClass>::bucket_addr(i);

  }

  // Check class loader constraints

  bool add_entry(Symbol* name, InstanceKlass* klass1, Handle loader1,

                                    InstanceKlass* klass2, Handle loader2);

  // Note:  The main entry point for this module is via SystemDictionary.

  // SystemDictionary::check_signature_loaders(Symbol* signature,

  //                                           Handle loader1, Handle loader2,

  //                                           bool is_method, TRAPS)

  InstanceKlass* find_constrained_klass(Symbol* name, Handle loader);

  // Class loader constraints

  void ensure_loader_constraint_capacity(LoaderConstraintEntry *p, int nfree);

  void extend_loader_constraint(LoaderConstraintEntry* p, Handle loader,

                                InstanceKlass* klass);

  void merge_loader_constraints(LoaderConstraintEntry** pp1,

                                LoaderConstraintEntry** pp2, InstanceKlass* klass);

  bool check_or_update(InstanceKlass* k, Handle loader, Symbol* name);

  void purge_loader_constraints();

  void verify(Dictionary* dictionary, PlaceholderTable* placeholders);

#ifndef PRODUCT

  void print();

#endif

};

class LoaderConstraintEntry : public HashtableEntry<InstanceKlass*, mtClass> {

  friend class VMStructs;

private:

  Symbol*                _name;                   // class name

  int                    _num_loaders;

  int                    _max_loaders;

  // Loader constraints enforce correct linking behavior.

  // Thus, it really operates on ClassLoaderData which represents linking domain,

  // not class loaders.

  ClassLoaderData**              _loaders;                // initiating loaders

public:

  InstanceKlass* klass() { return literal(); }

  InstanceKlass** klass_addr() { return literal_addr(); }

  void set_klass(InstanceKlass* k) { set_literal(k); }

  LoaderConstraintEntry* next() {

    return (LoaderConstraintEntry*)HashtableEntry<InstanceKlass*, mtClass>::next();

  }

  LoaderConstraintEntry** next_addr() {

    return (LoaderConstraintEntry**)HashtableEntry<InstanceKlass*, mtClass>::next_addr();

  }

  void set_next(LoaderConstraintEntry* next) {

    HashtableEntry<InstanceKlass*, mtClass>::set_next(next);

  }

  Symbol* name() { return _name; }

  void set_name(Symbol* name) {

    _name = name;

    if (name != NULL) name->increment_refcount();

  }

  int num_loaders() { return _num_loaders; }

  void set_num_loaders(int i) { _num_loaders = i; }

  int max_loaders() { return _max_loaders; }

  void set_max_loaders(int i) { _max_loaders = i; }

  ClassLoaderData** loaders() { return _loaders; }

  void set_loaders(ClassLoaderData** loaders) { _loaders = loaders; }

  ClassLoaderData* loader_data(int i) { return _loaders[i]; }

  void set_loader_data(int i, ClassLoaderData* p) { _loaders[i] = p; }

  // convenience

  void set_loader(int i, oop p);

};

#endif // SHARE_VM_CLASSFILE_LOADERCONSTRAINTS_HPP