/*

 * 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/recorder/checkpoint/jfrCheckpointManager.hpp"

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

#include "jfr/utilities/jfrBlob.hpp"

#include "jfr/writers/jfrBigEndianWriter.hpp"

JfrCheckpointFlush::JfrCheckpointFlush(Type* old, size_t used, size_t requested, Thread* t) :

  _result(JfrCheckpointManager::flush(old, used, requested, t)) {}

  _time(JfrTicks::now()),

  _offset(0),

  _count(0),

  _header(header) {

  assert(this->is_acquired(), "invariant");

  assert(0 == this->current_offset(), "invariant");

  if (_header) {

    reserve(sizeof(JfrCheckpointEntry));

  }

}

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

  JfrBigEndianWriter be_writer(pos, sizeof(JfrCheckpointEntry));

  be_writer.write(size);

  be_writer.write(time);

  be_writer.write(JfrTicks::now().value() - time);

  be_writer.write(type_count);

  assert(be_writer.is_valid(), "invariant");

}

JfrCheckpointWriter::~JfrCheckpointWriter() {

  assert(this->is_acquired(), "invariant");

  if (!this->is_valid() || !_header) {

    release();

    return;

  }

  if (0 == count()) {

    assert(this->used_size() == sizeof(JfrCheckpointEntry), "invariant");

    this->seek(_offset);

    release();

    return;

  }

  assert(_header, "invariant");

  assert(this->is_valid(), "invariant");

  assert(count() > 0, "invariant");

  assert(this->used_size() > sizeof(JfrCheckpointEntry), "invariant");

  const int64_t size = this->current_offset();

  assert(size + this->start_pos() == this->current_pos(), "invariant");

  release();

}

u4 JfrCheckpointWriter::count() const {

  return _count;

}

void JfrCheckpointWriter::set_count(u4 count) {

  _count = count;

}

void JfrCheckpointWriter::release() {

  assert(this->is_acquired(), "invariant");

  if (!this->is_valid() || this->used_size() == 0) {

    return;

  }

  assert(this->used_size() > 0, "invariant");

  // write through to backing storage

  this->commit();

  assert(0 == this->current_offset(), "invariant");

}

void JfrCheckpointWriter::write_type(JfrTypeId type_id) {

  assert(type_id < TYPES_END, "invariant");

  write<u8>(type_id);

  increment();

}

void JfrCheckpointWriter::write_key(u8 key) {

  write(key);

}

void JfrCheckpointWriter::increment() {

  ++_count;

}

void JfrCheckpointWriter::write_count(u4 nof_entries) {

  write(nof_entries);

}

void JfrCheckpointWriter::write_count(u4 nof_entries, int64_t offset) {

  write_padded_at_offset(nof_entries, offset);

}

const u1* JfrCheckpointWriter::session_data(size_t* size, bool move /* false */, const JfrCheckpointContext* ctx /* 0 */) {

  assert(this->is_acquired(), "wrong state!");

  if (!this->is_valid()) {

    *size = 0;

    return NULL;

  }

  if (ctx != NULL) {

    const u1* session_start_pos = this->start_pos() + ctx->offset;

    *size = this->current_pos() - session_start_pos;

    return session_start_pos;

  }

  *size = this->used_size();

  assert(this->start_pos() + *size == this->current_pos(), "invariant");

  _header = false; // the header was just written

  if (move) {

    this->seek(_offset);

  }

  return this->start_pos();

}

const JfrCheckpointContext JfrCheckpointWriter::context() const {

  JfrCheckpointContext ctx;

  ctx.offset = this->current_offset();

  ctx.count = this->count();

  return ctx;

}

void JfrCheckpointWriter::set_context(const JfrCheckpointContext ctx) {

  this->seek(ctx.offset);

  set_count(ctx.count);

}

bool JfrCheckpointWriter::has_data() const {

  return this->used_size() > sizeof(JfrCheckpointEntry);

}

JfrBlobHandle JfrCheckpointWriter::copy(const JfrCheckpointContext* ctx /* 0 */) {

  size_t size = 0;

  const u1* data = session_data(&size, false, ctx);

  return JfrBlob::make(data, size);

}

JfrBlobHandle JfrCheckpointWriter::move(const JfrCheckpointContext* ctx /* 0 */) {

  size_t size = 0;

  const u1* data = session_data(&size, true, ctx);

  JfrBlobHandle blob = JfrBlob::make(data, size);

  if (ctx != NULL) {

    const_cast<JfrCheckpointContext*>(ctx)->count = 0;

    set_context(*ctx);

  }

  return blob;

}