Encoder_.h

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#ifndef Cpl_Text_Frame_Encoder_x_h_
#define Cpl_Text_Frame_Encoder_x_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/Text/Frame/Encoder.h"
 
 
 
///
namespace Cpl {
///
namespace Text {
///
namespace Frame {
 
 
 
/** This Private Namespace partially concrete class implements common/helper
    method for supporting the Encoder API. There is no checking/enforcement
    of the content of the Frame (e.g. it will accept non-ASCII character)
    except for the SOF, EOF, and ESC characters.
 */
class Encoder_ : public Encoder
{
protected:
    /// Output/Frame state
    bool                m_inFrame;
 
    /// SOF character
    const char          m_sof;
 
    /// EOF character
    const char          m_eof;
 
    /// Escape character
    const char          m_esc;
 
    /// Remember my newline option
    const bool          m_appendNewline;
 
 
 
protected:
    /** Constructor.  The 'appendNewline' argument when set to true will
        append a newline character to the output stream AFTER the EOF
        character (this can make for more human readable output stream).
 
        NOTES:
 
            o If 'startOfFrame' is '\0', then Encoder will begin the
              frame WITHOUT inserting a SOF character.  This is useful
              when there application desires/has multiple start-of-frame
              characters for a given frame.
 
            o If 'escapeChar' is '\0', then Encoder will NOT escape any
              characters - buyers beware when using this feature!
     */
    Encoder_( char startOfFrame, char endOfFrame, char escapeChar, bool appendNewline=true );
 
 
public:
    /// See Cpl::Text::Frame::Encoder
    bool startFrame( void ) noexcept;
 
    /// See Cpl::Text::Frame::Encoder
    bool output( char src ) noexcept;
 
    /// See Cpl::Text::Frame::Encoder
    bool output( const char* src ) noexcept;
 
    /// See Cpl::Text::Frame::Encoder
    bool output( const char* src, size_t numBytes ) noexcept;
 
    /// See Cpl::Text::Frame::Encoder
    bool endFrame( void ) noexcept;
 
 
protected:
    /// Helper method - implemented by the child class
    virtual bool start( char src ) noexcept = 0;
 
    /// Helper method - implemented by the child class
    virtual bool start() noexcept = 0;
 
    /// Helper method - implemented by the child class
    virtual bool append( char src ) noexcept = 0;
 
    /** Returns the encoded/escaped value for the specified special character.  
        The default implementation simply returns 'charToBeEscaped'
     */
    virtual char encodeChar( char charToBeEscaped );
};
 
 
 
 
};      // end namespaces
};
};
#endif  // end header latch