cycleDataLockedStageReader.I

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/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file cycleDataLockedStageReader.I
 * @author drose
 * @date 2006-04-30
 */

#ifndef CPPPARSER

#ifdef DO_PIPELINING
// This is the implementation for full support of pipelining (as well as the
// sanity-check only implementation).

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
CycleDataLockedStageReader(const PipelineCycler<CycleDataType> &cycler,
                           int stage, Thread *current_thread) :
  _cycler(&cycler),
  _current_thread(current_thread),
  _stage(stage)
{
  _pointer = _cycler->read_stage(_stage, _current_thread);
  nassertv(_pointer != nullptr);
}

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
CycleDataLockedStageReader(const CycleDataLockedStageReader<CycleDataType> &copy) :
  _cycler(copy._cycler),
  _current_thread(copy._current_thread),
  _pointer(copy._pointer),
  _stage(copy._stage)
{
  nassertv(_pointer != nullptr);
  _cycler->increment_read(_pointer);
}

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
CycleDataLockedStageReader(CycleDataLockedStageReader<CycleDataType> &&from) noexcept :
  _cycler(from._cycler),
  _current_thread(from._current_thread),
  _pointer(from._pointer),
  _stage(from._stage)
{
  from._pointer = nullptr;
}

/**
 *
 */
template<class CycleDataType>
INLINE void CycleDataLockedStageReader<CycleDataType>::
operator = (const CycleDataLockedStageReader<CycleDataType> &copy) {
  nassertv(_pointer == nullptr);
  nassertv(_current_thread == copy._current_thread);

  _cycler = copy._cycler;
  _pointer = copy._pointer;
  _stage = copy._stage;

  nassertv(_pointer != nullptr);
  _cycler->increment_read(_pointer);
}

/**
 *
 */
template<class CycleDataType>
INLINE void CycleDataLockedStageReader<CycleDataType>::
operator = (CycleDataLockedStageReader<CycleDataType> &&from) noexcept {
  nassertv(_pointer == nullptr);
  nassertv(_current_thread == from._current_thread);

  _cycler = from._cycler;
  _pointer = from._pointer;
  _stage = from._stage;

  from._pointer = nullptr;
}

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
~CycleDataLockedStageReader() {
  if (_pointer != nullptr) {
    _cycler->release_read_stage(_stage, _pointer);
  }
}

/**
 * This provides an indirect member access to the actual CycleData data.
 */
template<class CycleDataType>
INLINE const CycleDataType *CycleDataLockedStageReader<CycleDataType>::
operator -> () const {
  nassertr(_pointer != nullptr, _cycler->cheat());
  return _pointer;
}

/**
 * This allows the CycleDataLockedStageReader to be passed to any function
 * that expects a const CycleDataType pointer.
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
operator const CycleDataType * () const {
  nassertr(_pointer != nullptr, _cycler->cheat());
  return _pointer;
}

/**
 * This is intended to be called only from CycleDataStageWriter when it
 * elevates the pointer from read to write status.  This function returns the
 * reader's pointer and relinquishes ownership of the pointer, rendering the
 * reader invalid for future reads.
 */
template<class CycleDataType>
INLINE const CycleDataType *CycleDataLockedStageReader<CycleDataType>::
take_pointer() {
  const CycleDataType *pointer = _pointer;
  _pointer = nullptr;
  nassertr(pointer != nullptr, _cycler->cheat());
  return pointer;
}

/**
 * Returns the Thread pointer of the currently-executing thread, as passed to
 * the constructor of this object.
 */
template<class CycleDataType>
INLINE Thread *CycleDataLockedStageReader<CycleDataType>::
get_current_thread() const {
  return _current_thread;
}

#else  // !DO_PIPELINING
// This is the trivial, do-nothing implementation.

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
CycleDataLockedStageReader(const PipelineCycler<CycleDataType> &cycler, int,
                           Thread *) {
  _pointer = cycler.cheat();
}

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
CycleDataLockedStageReader(const CycleDataLockedStageReader<CycleDataType> &copy) :
  _pointer(copy._pointer)
{
}

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
CycleDataLockedStageReader(CycleDataLockedStageReader<CycleDataType> &&from) noexcept :
  _pointer(from._cycler)
{
  from._pointer = nullptr;
}

/**
 *
 */
template<class CycleDataType>
INLINE void CycleDataLockedStageReader<CycleDataType>::
operator = (const CycleDataLockedStageReader<CycleDataType> &copy) {
  _pointer = copy._pointer;
}

/**
 *
 */
template<class CycleDataType>
INLINE void CycleDataLockedStageReader<CycleDataType>::
operator = (CycleDataLockedStageReader<CycleDataType> &&from) noexcept {
  nassertv(_pointer == nullptr);

  _pointer = from._pointer;
  from._pointer = nullptr;
}

/**
 *
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
~CycleDataLockedStageReader() {
}

/**
 * This provides an indirect member access to the actual CycleData data.
 */
template<class CycleDataType>
INLINE const CycleDataType *CycleDataLockedStageReader<CycleDataType>::
operator -> () const {
  return _pointer;
}

/**
 * This allows the CycleDataLockedStageReader to be passed to any function
 * that expects a const CycleDataType pointer.
 */
template<class CycleDataType>
INLINE CycleDataLockedStageReader<CycleDataType>::
operator const CycleDataType * () const {
  return _pointer;
}

/**
 * This is intended to be called only from CycleDataStageWriter when it
 * elevates the pointer from read to write status.  This function returns the
 * reader's pointer and relinquishes ownership of the pointer, rendering the
 * reader invalid for future reads.
 */
template<class CycleDataType>
INLINE const CycleDataType *CycleDataLockedStageReader<CycleDataType>::
take_pointer() {
  return _pointer;
}

/**
 * Returns the Thread pointer of the currently-executing thread, as passed to
 * the constructor of this object.
 */
template<class CycleDataType>
INLINE Thread *CycleDataLockedStageReader<CycleDataType>::
get_current_thread() const {
  return Thread::get_current_thread();
}

#endif  // DO_PIPELINING
#endif  // CPPPARSER