src/protozero/message_handle.cc

/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "perfetto/protozero/message_handle.h"

#include <utility>

#include "perfetto/protozero/message.h"

namespace protozero {

MessageHandleBase::MessageHandleBase(Message* message) : message_(message) {
#if PERFETTO_DCHECK_IS_ON()
  generation_ = message_ ? message->generation_ : 0;
  if (message_)
    message_->set_handle(this);
#endif
}

MessageHandleBase::~MessageHandleBase() {
  if (message_) {
#if PERFETTO_DCHECK_IS_ON()
    PERFETTO_DCHECK(generation_ == message_->generation_);
#endif
    FinalizeMessage();
  }
}

MessageHandleBase::MessageHandleBase(MessageHandleBase&& other) noexcept {
  Move(std::move(other));
}

MessageHandleBase& MessageHandleBase::operator=(MessageHandleBase&& other) {
  // If the current handle was pointing to a message and is being reset to a new
  // one, finalize the old message. However, if the other message is the same as
  // the one we point to, don't finalize.
  if (message_ && message_ != other.message_)
    FinalizeMessage();
  Move(std::move(other));
  return *this;
}

void MessageHandleBase::Move(MessageHandleBase&& other) {
  message_ = other.message_;
  other.message_ = nullptr;
#if PERFETTO_DCHECK_IS_ON()
  if (message_) {
    generation_ = message_->generation_;
    message_->set_handle(this);
  }
#endif
}

}  // namespace protozero