/*

 * Copyright (c) 2018, 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 "gc/shared/ptrQueue.hpp"

#include "runtime/mutex.hpp"

#include "unittest.hpp"

// Some basic testing of BufferNode::Allocator.

TEST_VM(PtrQueueBufferAllocatorTest, test) {

  Mutex m(Mutex::leaf, "PtrQueueBufferAllocatorTest",

          false, Mutex::_safepoint_check_never);

  BufferNode::Allocator allocator(256, &m);

  // Allocate some new nodes for use in testing.

  BufferNode* nodes[10] = {};

  const size_t node_count = ARRAY_SIZE(nodes);

  for (size_t i = 0; i < node_count; ++i) {

    ASSERT_EQ(0u, allocator.free_count());

    nodes[i] = allocator.allocate();

  }

  // Release the nodes, adding them to the allocator's free list.

  for (size_t i = 0; i < node_count; ++i) {

    ASSERT_EQ(i, allocator.free_count());

    allocator.release(nodes[i]);

    if (i == 0) {

    } else {

      ASSERT_EQ(nodes[i - 1], nodes[i]->next());

    }

  }

  // Allocate nodes from the free list.

  for (size_t i = 0; i < node_count; ++i) {

    size_t j = node_count - i;

    ASSERT_EQ(j, allocator.free_count());

    ASSERT_EQ(nodes[j - 1], allocator.allocate());

  }

  ASSERT_EQ(0u, allocator.free_count());

  // Release nodes back to the free list.

  for (size_t i = 0; i < node_count; ++i) {

    allocator.release(nodes[i]);

  }

  ASSERT_EQ(node_count, allocator.free_count());

  // Destroy some nodes in the free list.

  // We don't have a way to verify destruction, but we can at

  // leat verify we don't crash along the way.

  allocator.reduce_free_list();

  // destroy allocator.

}