/*

 * 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.

 *

 */

#include "precompiled.hpp"

#include "services/memPtr.hpp"

#include "services/memTracker.hpp"

volatile jint SequenceGenerator::_seq_number = 1;

volatile unsigned long SequenceGenerator::_generation = 1;

NOT_PRODUCT(jint SequenceGenerator::_max_seq_number = 1;)

jint SequenceGenerator::next() {

  jint seq = Atomic::add(1, &_seq_number);

  if (seq < 0) {

    MemTracker::shutdown(MemTracker::NMT_sequence_overflow);

  }

  assert(seq > 0, "counter overflow");

  NOT_PRODUCT(_max_seq_number = (seq > _max_seq_number) ? seq : _max_seq_number;)

  return seq;

}