/*

 * Copyright (c) 2019, 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 "jfr/support/jfrThreadLocal.hpp"

#include "jfr/utilities/jfrThreadIterator.hpp"

#include "runtime/thread.inline.hpp"

static bool thread_inclusion_predicate(Thread* t) {

  assert(t != NULL, "invariant");

}

static bool java_thread_inclusion_predicate(JavaThread* jt) {

  assert(jt != NULL, "invariant");

  return thread_inclusion_predicate(jt) && jt->thread_state() != _thread_new;

}

static JavaThread* next_java_thread(JavaThreadIteratorWithHandle& iter) {

  JavaThread* next = iter.next();

  while (next != NULL && !java_thread_inclusion_predicate(next)) {

    next = iter.next();

  }

  return next;

}

static NonJavaThread* next_non_java_thread(NonJavaThread::Iterator& iter) {

  NonJavaThread* next = NULL;

  while (!iter.end()) {

    next = iter.current();

    iter.step();

    assert(next != NULL, "invariant");

    if (!thread_inclusion_predicate(next)) {

      continue;

    }

  }

  return next;

}

JfrJavaThreadIteratorAdapter::JfrJavaThreadIteratorAdapter() : _iter(), _next(next_java_thread(_iter)) {}

JavaThread* JfrJavaThreadIteratorAdapter::next() {

  assert(has_next(), "invariant");

  Type* const temp = _next;

  assert(java_thread_inclusion_predicate(temp), "invariant");

  _next = next_java_thread(_iter);

  assert(temp != _next, "invariant");

  return temp;

}

JfrNonJavaThreadIteratorAdapter::JfrNonJavaThreadIteratorAdapter() : _iter(), _next(next_non_java_thread(_iter)) {}

bool JfrNonJavaThreadIteratorAdapter::has_next() const {

  return _next != NULL;

}

NonJavaThread* JfrNonJavaThreadIteratorAdapter::next() {

  assert(has_next(), "invariant");

  Type* const temp = _next;

  assert(thread_inclusion_predicate(temp), "invariant");

  _next = next_non_java_thread(_iter);

  assert(temp != _next, "invariant");

  return temp;

}

// explicit instantiations

template class JfrThreadIterator<JfrJavaThreadIteratorAdapter, StackObj>;

template class JfrThreadIterator<JfrNonJavaThreadIteratorAdapter, StackObj>;