Null.h

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#ifndef Cpl_Io_File_Null_h_
#define Cpl_Io_File_Null_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/Io/File/InputOutputApi.h"
 
 
///
namespace Cpl {
///
namespace Io {
///
namespace File {
 
 
/** This concrete class implements a NULL InputOutputApi File that all of its
    input operations return 'End-of-File' (i.e. return false) and all output is
    dropped in the proverbial bit-bucket and goes no where!  Note: The write()
    methods always return true (i.e. no error).
 */
class Null : public InputOutputApi
{
public:
    /// Constructor
    Null();
 
    /// Destructor
    ~Null();
 
 
public:
    /// Pull in overloaded methods from base class
    using Cpl::Io::File::InputOutputApi::read;
 
    /// See Cpl::Io::Input
    bool read( void* buffer, int numBytes, int& bytesRead );
 
    /// See Cpl::Io::Input
    bool available();
 
 
public:
    /// Pull in overloaded methods from base class
    using Cpl::Io::File::InputOutputApi::write;
 
    /// See Cpl::Io::Output
    bool write( const void* buffer, int maxBytes, int& bytesWritten );
 
    /// See Cpl::Io::Output
    void flush();
 
    /// See Cpl::Io::IsEos (is equivalent to isEof())
    bool isEos();
    
    /// See Cpl::Io::Close. Note: Once closed() has been called, all of the write() and ObjecApi methods will return false
    void close();
 
 
public:
    /// See Cpl::Io::File::ObjectApi
    bool isEof();
 
    /// See Cpl::Io::File::ObjectApi
    bool length( unsigned long& len );
 
    /// See Cpl::Io::File::ObjectApi
    bool currentPos( unsigned long& curPos );
 
    /// See Cpl::Io::File::ObjectApi
    bool setRelativePos( long deltaOffset );
 
    /// See Cpl::Io::File::ObjectApi
    bool setAbsolutePos( unsigned long newoffset );
 
    /// See Cpl::Io::File::ObjectApi
    bool setToEof();
 
 
protected:
    /// Track my opened/closed state
    bool m_opened;
 
 
};
 
};      // end namespaces
};
};
#endif  // end header latch