etl/include/etl/reference_counted_message.h

/******************************************************************************
The MIT License(MIT)

Embedded Template Library.
https://github.com/ETLCPP/etl
https://www.etlcpp.com

Copyright(c) 2017 jwellbelove

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******************************************************************************/

#ifndef ETL_REFERENCE_COUNTED_MESSAGE_INCLUDED
#define ETL_REFERENCE_COUNTED_MESSAGE_INCLUDED

#include <stdint.h>

#include "platform.h"
#include "message.h"
#include "atomic.h"
#include "reference_counted_object.h"

namespace etl
{
  //***************************************************************************
  // Base class for all reference counted messages.
  //***************************************************************************
  class ireference_counted_message
  {
  public:

    virtual const etl::imessage& get_message() const = 0; ///< Get a const reference to the message.

    virtual etl::ireference_counted_object& get_reference_counter() = 0;             ///< Get a reference to the reference counter.
    virtual const etl::ireference_counted_object& get_reference_counter() const = 0; ///< Get a const reference to the reference counter.
  };

  //***************************************************************************
  // Reference counted message type.
  //***************************************************************************
  template <typename TMessage, typename TCounter>
  class reference_counted_message : public etl::ireference_counted_message
  {
  public:

    typedef TMessage message_type;
    typedef TCounter counter_type;

    //***************************************************************************
    /// Constructor
    /// \param msg The message to count.
    //***************************************************************************
    reference_counted_message(const TMessage& msg_)
      : rc_object(msg_)
    {
    }

    //***************************************************************************
    /// Get a const reference to the message.
    /// \return A const reference to the message.
    //***************************************************************************
    virtual const TMessage& get_message() const ETL_OVERRIDE
    {
      return rc_object.get_object();
    }

    //***************************************************************************
    /// Get a reference to the reference counter.
    /// \return A reference to the reference counter.
    //***************************************************************************
    virtual etl::ireference_counted_object& get_reference_counter() ETL_OVERRIDE
    {
      return rc_object;
    }

    //***************************************************************************
    /// Get a const reference to the reference counter.
    /// \return A const reference to the reference counter.
    //***************************************************************************
    virtual const etl::ireference_counted_object& get_reference_counter() const ETL_OVERRIDE
    {
      return rc_object;
    }

  private:

    /// The reference counted object.
    etl::reference_counted_object<TMessage, TCounter> rc_object;
  };

#if ETL_HAS_ATOMIC
  //***************************************************************************
  /// Class for creating reference counted messages using an atomic counter.
  /// \tparam TMessage The type to be reference counted.
  //***************************************************************************
  template <typename TMessage>
  class atomic_counted_message : virtual public etl::reference_counted_message<TMessage, etl::atomic_int32_t>
  {
  public:

    //***************************************************************************
    /// Constructor.
    /// \param msg The message to count.
    //***************************************************************************
    atomic_counted_message(const TMessage& msg_)
      : reference_counted_message<TMessage, etl::atomic_int32_t>(msg_)
    {
    }

    typedef typename reference_counted_message<TMessage, etl::atomic_int32_t>::message_type message_type;
    typedef typename reference_counted_message<TMessage, etl::atomic_int32_t>::counter_type counter_type;
  };
#endif

  //***************************************************************************
  // Uncounted message type.
  //***************************************************************************
  template <typename TMessage>
  class reference_counted_message<TMessage, void> : virtual public etl::ireference_counted_message
  {
  public:

    typedef TMessage message_type;
    typedef void     counter_type;

    //***************************************************************************
    /// Constructor
    /// \param msg The message to count.
    //***************************************************************************
    reference_counted_message(const TMessage& msg_)
      : rc_object(msg_)
    {
    }

    //***************************************************************************
    /// Get a const reference to the message.
    /// \return A const reference to the message.
    //***************************************************************************
    virtual const TMessage& get_message() const ETL_OVERRIDE
    {
      return rc_object.get_object();
    }

    //***************************************************************************
    /// Get a reference to the reference counter.
    /// \return A reference to the reference counter.
    //***************************************************************************
    virtual etl::ireference_counted_object& get_reference_counter() ETL_OVERRIDE
    {
      return rc_object;
    }

    //***************************************************************************
    /// Get a const reference to the reference counter.
    /// \return A const reference to the reference counter.
    //***************************************************************************
    virtual const etl::ireference_counted_object& get_reference_counter() const ETL_OVERRIDE
    {
      return rc_object;
    }

  private:

    /// The reference counted object.
    etl::reference_counted_object<TMessage, void> rc_object;
  };

  //***************************************************************************
  /// Synonym for reference_counted_message<TMessage, void>
  /// \tparam TObject  The type stored in the object.
  //***************************************************************************
  template <typename TMessage>
  class uncounted_message : public etl::reference_counted_message<TMessage, void>
  {
  public:

    //***************************************************************************
    /// Constructor.
    //***************************************************************************
    uncounted_message(const TMessage& msg_)
      : reference_counted_message<TMessage, void>(msg_)
    {
    }

    typedef typename reference_counted_message<TMessage, void>::message_type message_type;
    typedef typename reference_counted_message<TMessage, void>::counter_type counter_type;
  };
}

#endif