/*

 * Copyright (c) 2012, 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/jni/jfrJavaSupport.hpp"

#include "jfr/recorder/repository/jfrChunkRotation.hpp"

#include "jfr/recorder/repository/jfrChunkWriter.hpp"

#include "runtime/handles.inline.hpp"

static jobject chunk_monitor = NULL;

static int64_t threshold = 0;

static bool rotate = false;

static jobject install_chunk_monitor(Thread* thread) {

  assert(chunk_monitor == NULL, "invariant");

  // read static field

  HandleMark hm(thread);

  static const char klass[] = "jdk/jfr/internal/JVM";

  static const char field[] = "FILE_DELTA_CHANGE";

  static const char signature[] = "Ljava/lang/Object;";

  JavaValue result(T_OBJECT);

  JfrJavaArguments field_args(&result, klass, field, signature, thread);

  JfrJavaSupport::get_field_global_ref(&field_args, thread);

  chunk_monitor = result.get_jobject();

  return chunk_monitor;

}

// lazy install

static jobject get_chunk_monitor(Thread* thread) {

  return chunk_monitor != NULL ? chunk_monitor : install_chunk_monitor(thread);

}

static void notify() {

  Thread* const thread = Thread::current();

  JfrJavaSupport::notify_all(get_chunk_monitor(thread), thread);

}

void JfrChunkRotation::evaluate(const JfrChunkWriter& writer) {

  assert(threshold > 0, "invariant");

  if (rotate) {

    // already in progress

    return;

  }

  if (writer.size_written() > threshold) {

    rotate = true;

    notify();

  }

}

bool JfrChunkRotation::should_rotate() {

  return rotate;

}

void JfrChunkRotation::on_rotation() {

  rotate = false;

}

void JfrChunkRotation::set_threshold(int64_t bytes) {

  threshold = bytes;

}