/*

 * Copyright (c) 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.

 *

 */

#include "precompiled.hpp"

#include "classfile/protectionDomainCache.hpp"

#include "classfile/systemDictionary.hpp"

#include "memory/iterator.hpp"

#include "memory/resourceArea.hpp"

#include "oops/oop.inline.hpp"

#include "utilities/hashtable.inline.hpp"

unsigned int ProtectionDomainCacheTable::compute_hash(Handle protection_domain) {

  // Identity hash can safepoint, so keep protection domain in a Handle.

  return (unsigned int)(protection_domain->identity_hash());

}

int ProtectionDomainCacheTable::index_for(Handle protection_domain) {

  return hash_to_index(compute_hash(protection_domain));

}

ProtectionDomainCacheTable::ProtectionDomainCacheTable(int table_size)

  : Hashtable<oop, mtClass>(table_size, sizeof(ProtectionDomainCacheEntry))

{

}

void ProtectionDomainCacheTable::unlink(BoolObjectClosure* is_alive) {

  assert(SafepointSynchronize::is_at_safepoint(), "must be");

  for (int i = 0; i < table_size(); ++i) {

    ProtectionDomainCacheEntry** p = bucket_addr(i);

    ProtectionDomainCacheEntry* entry = bucket(i);

    while (entry != NULL) {

      if (is_alive->do_object_b(entry->literal())) {

        p = entry->next_addr();

      } else {

        if (log_is_enabled(Debug, protectiondomain)) {

          outputStream* log = Log(protectiondomain)::debug_stream();

          log->print("protection domain unlinked: ");

          entry->literal()->print_value_on(log);

          log->cr();

        }

        *p = entry->next();

        free_entry(entry);

      }

      entry = *p;

    }

  }

}

void ProtectionDomainCacheTable::oops_do(OopClosure* f) {

  for (int index = 0; index < table_size(); index++) {

    for (ProtectionDomainCacheEntry* probe = bucket(index);

                                     probe != NULL;

                                     probe = probe->next()) {

      probe->oops_do(f);

    }

  }

}

#ifndef PRODUCT

void ProtectionDomainCacheTable::print() {

  tty->print_cr("Protection domain cache table (table_size=%d, classes=%d)",

                table_size(), number_of_entries());

  for (int index = 0; index < table_size(); index++) {

    for (ProtectionDomainCacheEntry* probe = bucket(index);

                                     probe != NULL;

                                     probe = probe->next()) {

      probe->print();

    }

  }

}

void ProtectionDomainCacheEntry::print() {

  tty->print_cr("entry " PTR_FORMAT " value " PTR_FORMAT " next " PTR_FORMAT,

                p2i(this), p2i(literal()), p2i(next()));

}

#endif

void ProtectionDomainCacheTable::verify() {

}

void ProtectionDomainCacheEntry::verify() {

  guarantee(literal()->is_oop(), "must be an oop");

}

ProtectionDomainCacheEntry* ProtectionDomainCacheTable::get(Handle protection_domain) {

  unsigned int hash = compute_hash(protection_domain);

  int index = hash_to_index(hash);

  ProtectionDomainCacheEntry* entry = find_entry(index, protection_domain);

  if (entry == NULL) {

    entry = add_entry(index, hash, protection_domain);

  }

  return entry;

}

ProtectionDomainCacheEntry* ProtectionDomainCacheTable::find_entry(int index, Handle protection_domain) {

  for (ProtectionDomainCacheEntry* e = bucket(index); e != NULL; e = e->next()) {

    if (e->protection_domain() == protection_domain()) {

      return e;

    }

  }

  return NULL;

}

ProtectionDomainCacheEntry* ProtectionDomainCacheTable::add_entry(int index, unsigned int hash, Handle protection_domain) {

  assert_locked_or_safepoint(SystemDictionary_lock);

  assert(index == index_for(protection_domain), "incorrect index?");

  assert(find_entry(index, protection_domain) == NULL, "no double entry");

  ProtectionDomainCacheEntry* p = new_entry(hash, protection_domain);

  Hashtable<oop, mtClass>::add_entry(index, p);

  return p;

}