Void.h

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#ifndef Cpl_Dm_Mp_Void_h_
#define Cpl_Dm_Mp_Void_h_
/*-----------------------------------------------------------------------------
* This file is part of the Colony.Core Project.  The Colony.Core Project is an
* open source project with a BSD type of licensing agreement.  See the license
* agreement (license.txt) in the top/ directory or on the Internet at
* http://integerfox.com/colony.core/license.txt
*
* Copyright (c) 2014-2022  John T. Taylor
*
* Redistributions of the source code must retain the above copyright notice.
*----------------------------------------------------------------------------*/
/** @file */
 
 
#include "Cpl/Dm/Mp/Numeric.h"
 
///
namespace Cpl {
///
namespace Dm {
///
namespace Mp {
 
 
/** This class provides a concrete implementation for a Point who's data is a
    void pointer.  
    
    On general principle there should NOT be model point type that is generic 
    (it goes against the whole 'model-points-are-type-safe' thingy). HOWEVER, 
    there are some cases where it is desirable to have MP contain a pointer - 
    where the actual definition of what that pointer points to is 'not visible' 
    
    Shorter version: DO NOT USE THIS MODEL POINT TYPE UNLESS YOU HAVE NO 
    ALTERNATIVE. Not wanting to take the time to create a new model point type
    (with test code) is NOT an acceptable excuse for using this model point 
    type.
 
    The toJSON()/fromJSON format is:
        \code
 
        { name:"<mpname>", type:"<mptypestring>", valid:true|false, seqnum:nnnn, locked:true|false, val:"<hexvalue>" }
 
        \endcode
 
 NOTE: All methods in this class ARE thread Safe unless explicitly
          documented otherwise.
 */
class Void : public Pointer_<Void>
{
public:
    /// Constructor. Invalid MP. 
    Void( Cpl::Dm::ModelDatabase& myModelBase, const char* symbolicName )
        :Pointer_<Void>( myModelBase, symbolicName )
    {
    }
 
    /// Constructor. Valid MP.  Requires an initial value
    Void( Cpl::Dm::ModelDatabase& myModelBase, const char* symbolicName, void* initialValue )
        : Pointer_<Void>( myModelBase, symbolicName, initialValue )
    {
    }
 
 
public:
    /// Type safe read. See Cpl::Dm::ModelPoint
    inline bool read( void*& dstData, uint16_t* seqNumPtr = 0 ) const noexcept
    {
        return readData( &dstData, sizeof( void* ), seqNumPtr );
    }
 
    /// Type safe write. See Cpl::Dm::ModelPoint
    inline uint16_t write( void* newValue, Cpl::Dm::ModelPoint::LockRequest_T lockRequest = Cpl::Dm::ModelPoint::eNO_REQUEST ) noexcept
    {
        return writeData( &newValue, sizeof( void* ), lockRequest );
    }
 
public:
    /// Type safe subscriber
    typedef Cpl::Dm::Subscriber<Void> Observer;
 
    /// See Cpl::Dm::ModelPointCommon
    inline bool readAndSync( void*& dstData, SubscriberApi& observerToSync )
    {
        return ModelPointCommon_::readAndSync( &dstData, sizeof( void* ), observerToSync );
    }
 
    ///  See Cpl::Dm::ModelPoint.
    const char* getTypeAsText() const noexcept
    {
        return "Cpl::Dm::Mp::Void";
    }
};
 
 
 
};      // end namespaces
};
};
#endif  // end header latch