reference_counted_message.h

/******************************************************************************
The MIT License(MIT)
 
Embedded Template Library.
https://github.com/ETLCPP/etl
https://www.etlcpp.com
 
Copyright(c) 2021 John Wellbelove
 
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files(the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and / or sell
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The above copyright notice and this permission notice shall be included in all
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
******************************************************************************/
 
#ifndef ETL_REFERENCE_COUNTED_MESSAGE_INCLUDED
#define ETL_REFERENCE_COUNTED_MESSAGE_INCLUDED
 
#include "platform.h"
#include "atomic.h"
#include "ireference_counted_message_pool.h"
#include "message.h"
#include "reference_counted_object.h"
#include "static_assert.h"
#include "type_traits.h"
 
#include <stdint.h>
 
namespace etl
{
  //***************************************************************************
  // Base class for all reference counted messages.
  //***************************************************************************
  class ireference_counted_message
  {
  public:
 
    virtual ~ireference_counted_message() {}
    ETL_NODISCARD
    virtual etl::imessage&           get_message()           = 0;             
    ETL_NODISCARD
    virtual const etl::imessage&     get_message() const     = 0;             
    ETL_NODISCARD
    virtual etl::ireference_counter& get_reference_counter() = 0;             
    ETL_NODISCARD
    virtual const etl::ireference_counter& get_reference_counter() const = 0; 
    virtual void                           release()                     = 0; 
  };
 
  //***************************************************************************
  // Reference counted message with a counter and owner.
  //***************************************************************************
  template <typename TMessage, typename TCounter>
  class reference_counted_message : public etl::ireference_counted_message
  {
  public:
 
    ETL_STATIC_ASSERT((etl::is_base_of<etl::imessage, TMessage>::value), "Not a message type");
 
    typedef TMessage message_type;
    typedef TCounter counter_type;
 
#if ETL_USING_CPP11
    //***************************************************************************
    //***************************************************************************
    template <typename... TArgs>
    reference_counted_message(etl::ireference_counted_message_pool& owner_, TArgs&&... args)
      : rc_object(etl::forward<TArgs>(args)...)
      , owner(owner_)
    {
    }
#endif
 
    //***************************************************************************
    //***************************************************************************
    reference_counted_message(const TMessage& msg_, etl::ireference_counted_message_pool& owner_)
      : rc_object(msg_)
      , owner(owner_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual TMessage& get_message() ETL_OVERRIDE
    {
      return rc_object.get_object();
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual const TMessage& get_message() const ETL_OVERRIDE
    {
      return rc_object.get_object();
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual etl::ireference_counter& get_reference_counter() ETL_OVERRIDE
    {
      return rc_object.get_reference_counter();
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual const etl::ireference_counter& get_reference_counter() const ETL_OVERRIDE
    {
      return rc_object.get_reference_counter();
    }
 
    //***************************************************************************
    //***************************************************************************
    virtual void release() ETL_OVERRIDE
    {
      owner.release(*this);
    }
 
  private:
 
    etl::reference_counted_object<TMessage, TCounter> rc_object; 
    etl::ireference_counted_message_pool&             owner;     
  };
 
  //***************************************************************************
  // A persistent message with no counter and owner.
  //***************************************************************************
  template <typename TMessage>
  class persistent_message : public etl::ireference_counted_message
  {
  public:
 
    ETL_STATIC_ASSERT((etl::is_base_of<etl::imessage, TMessage>::value), "Not a message type");
 
    typedef TMessage message_type;
    typedef void     counter_type;
 
    //***************************************************************************
    //***************************************************************************
    explicit persistent_message(const TMessage& msg_)
      : rc_object(msg_)
    {
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual TMessage& get_message() ETL_OVERRIDE
    {
      return rc_object.get_object();
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual const TMessage& get_message() const ETL_OVERRIDE
    {
      return rc_object.get_object();
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual etl::ireference_counter& get_reference_counter() ETL_OVERRIDE
    {
      return rc_object.get_reference_counter();
    }
 
    //***************************************************************************
    //***************************************************************************
    ETL_NODISCARD
    virtual const etl::ireference_counter& get_reference_counter() const ETL_OVERRIDE
    {
      return rc_object.get_reference_counter();
    }
 
    //***************************************************************************
    //***************************************************************************
    virtual void release() ETL_OVERRIDE
    {
      // Do nothing.
    }
 
  private:
 
    etl::reference_counted_object<TMessage, void> rc_object; 
  };
 
#if ETL_USING_CPP11 && ETL_HAS_ATOMIC
  //***************************************************************************
  //***************************************************************************
  template <typename TMessage>
  using atomic_counted_message = etl::reference_counted_message<TMessage, etl::atomic_int32_t>;
#endif
} // namespace etl
 
#endif