/*

 * Copyright (c) 2016, 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/metadata/jfrSerializer.hpp"

#include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"

#include "jfr/recorder/checkpoint/types/jfrType.hpp"

#include "jfr/recorder/checkpoint/types/jfrTypeManager.hpp"

#include "jfr/utilities/jfrDoublyLinkedList.hpp"

#include "jfr/utilities/jfrIterator.hpp"

#include "runtime/safepoint.hpp"

#include "runtime/thread.inline.hpp"

#include "utilities/exceptions.hpp"

#include "runtime/semaphore.hpp"

class JfrSerializerRegistration : public JfrCHeapObj {

 private:

  JfrSerializerRegistration* _next;

  JfrSerializerRegistration* _prev;

  JfrSerializer* _serializer;

  JfrTypeId _id;

  bool _permit_cache;

 public:

  JfrSerializerRegistration(JfrTypeId id, bool permit_cache, JfrSerializer* serializer) :

    _next(NULL), _prev(NULL), _serializer(serializer), _cache(), _id(id), _permit_cache(permit_cache) {}

  ~JfrSerializerRegistration() {

    delete _serializer;

  }

  JfrSerializerRegistration* next() const {

    return _next;

  }

  void set_next(JfrSerializerRegistration* next) {

    _next = next;

  }

  JfrSerializerRegistration* prev() const {

    return _prev;

  }

  void set_prev(JfrSerializerRegistration* prev) {

    _prev = prev;

  }

  JfrTypeId id() const {

    return _id;

  }

  void invoke(JfrCheckpointWriter& writer) const;

};

void JfrSerializerRegistration::invoke(JfrCheckpointWriter& writer) const {

  if (_cache.valid()) {

    writer.increment();

    _cache->write(writer);

    return;

  }

  const JfrCheckpointContext ctx = writer.context();

  // serialize the type id before invoking callback

  writer.write_type(_id);

  const intptr_t start = writer.current_offset();

  // invoke the serializer routine

  _serializer->serialize(writer);

  if (start == writer.current_offset() ) {

    // the serializer implementation did nothing, rewind to restore

    writer.set_context(ctx);

    return;

  }

  if (_permit_cache) {

    _cache = writer.copy(&ctx);

  }

}

class SerializerRegistrationGuard : public StackObj {

 private:

  static Semaphore _mutex_semaphore;

 public:

  SerializerRegistrationGuard() {

    _mutex_semaphore.wait();

  }

  ~SerializerRegistrationGuard() {

    _mutex_semaphore.signal();

  }

};

Semaphore SerializerRegistrationGuard::_mutex_semaphore(1);

typedef JfrDoublyLinkedList<JfrSerializerRegistration> List;

typedef StopOnNullIterator<const List> Iterator;

static List types;

static List safepoint_types;

void JfrTypeManager::clear() {

  SerializerRegistrationGuard guard;

  Iterator iter(types);

  JfrSerializerRegistration* registration;

  while (iter.has_next()) {

    registration = types.remove(iter.next());

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

    delete registration;

  }

  Iterator sp_type_iter(safepoint_types);

  while (sp_type_iter.has_next()) {

    registration = safepoint_types.remove(sp_type_iter.next());

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

    delete registration;

  }

}

void JfrTypeManager::write_types(JfrCheckpointWriter& writer) {

  const Iterator iter(types);

  while (iter.has_next()) {

    iter.next()->invoke(writer);

  }

}

void JfrTypeManager::write_safepoint_types(JfrCheckpointWriter& writer) {

  assert(SafepointSynchronize::is_at_safepoint(), "invariant");

  const Iterator iter(safepoint_types);

  while (iter.has_next()) {

    iter.next()->invoke(writer);

  }

}

void JfrTypeManager::write_type_set() {

  set.serialize(writer);

}

void JfrTypeManager::write_type_set_for_unloaded_classes() {

  assert_locked_or_safepoint(ClassLoaderDataGraph_lock);

  JfrCheckpointWriter writer(false, true, Thread::current());

  ClassUnloadTypeSet class_unload_set;

  class_unload_set.serialize(writer);

}

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

  JfrThreadConstant type_thread(jt);

  JfrCheckpointWriter writer(false, true, jt);

  writer.write_type(TYPE_THREAD);

  type_thread.serialize(writer);

  // create and install a checkpoint blob

}

void JfrTypeManager::write_thread_checkpoint(JavaThread* jt) {

  assert(jt != NULL, "JavaThread is NULL!");

  ResourceMark rm(jt);

}

#ifdef ASSERT

static void assert_not_registered_twice(JfrTypeId id, List& list) {

  const Iterator iter(list);

  while (iter.has_next()) {

    assert(iter.next()->id() != id, "invariant");

  }

}

#endif

static bool register_type(JfrTypeId id, bool require_safepoint, bool permit_cache, JfrSerializer* serializer) {

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

  JfrSerializerRegistration* const registration = new JfrSerializerRegistration(id, permit_cache, serializer);

  if (registration == NULL) {

    delete serializer;

    return false;

  }

  if (require_safepoint) {

    assert(!safepoint_types.in_list(registration), "invariant");

    DEBUG_ONLY(assert_not_registered_twice(id, safepoint_types);)

    safepoint_types.prepend(registration);

  } else {

    assert(!types.in_list(registration), "invariant");

    DEBUG_ONLY(assert_not_registered_twice(id, types);)

    types.prepend(registration);

  }

  return true;

}

bool JfrTypeManager::initialize() {

  SerializerRegistrationGuard guard;

  // register non-safepointing type serialization

  register_type(TYPE_FLAGVALUEORIGIN, false, true, new FlagValueOriginConstant());

  register_type(TYPE_INFLATECAUSE, false, true, new MonitorInflateCauseConstant());

  register_type(TYPE_GCCAUSE, false, true, new GCCauseConstant());

  register_type(TYPE_GCNAME, false, true, new GCNameConstant());

  register_type(TYPE_GCWHEN, false, true, new GCWhenConstant());

  register_type(TYPE_GCTHRESHOLDUPDATER, false, true, new GCThresholdUpdaterConstant());

  register_type(TYPE_METADATATYPE, false, true, new MetadataTypeConstant());

  register_type(TYPE_METASPACEOBJECTTYPE, false, true, new MetaspaceObjectTypeConstant());

  register_type(TYPE_REFERENCETYPE, false, true, new ReferenceTypeConstant());

  register_type(TYPE_NARROWOOPMODE, false, true, new NarrowOopModeConstant());

  register_type(TYPE_COMPILERPHASETYPE, false, true, new CompilerPhaseTypeConstant());

  register_type(TYPE_CODEBLOBTYPE, false, true, new CodeBlobTypeConstant());

  register_type(TYPE_VMOPERATIONTYPE, false, true, new VMOperationTypeConstant());

  register_type(TYPE_THREADSTATE, false, true, new ThreadStateConstant());

  // register safepointing type serialization

  register_type(TYPE_THREADGROUP, true, false, new JfrThreadGroupConstant());

  register_type(TYPE_THREAD, true, false, new JfrThreadConstantSet());

  return true;

}

// implementation for the static registration function exposed in the JfrSerializer api

bool JfrSerializer::register_serializer(JfrTypeId id, bool require_safepoint, bool permit_cache, JfrSerializer* serializer) {

  SerializerRegistrationGuard guard;

  return register_type(id, require_safepoint, permit_cache, serializer);

}