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C:/temp/src/j2k/Fred/String/StrData.hpp

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#ifndef __J2K__JString_Data_HPP__
#define __J2K__JString_Data_HPP__

#include <j2k/Fred/Basic.hpp>
#include <j2k/Fred/Boolean.hpp>
#include <j2k/Fred/StdTypes.hpp>

////////////////////////////////////////////////////////////////////////////
/// always allocate one extra character for '\0' termination assumes     ///
/// [optimistically] that data length will equal allocation length       ///
////////////////////////////////////////////////////////////////////////////
/// Something like 4 GigaBytes...                                        ///
////////////////////////////////////////////////////////////////////////////
#define JString_MAX   ( sizeof(size_t) )

/** ANDREA ***************************************************

  What do you think sizeof(size_t) will return ? Fortunately
  you never used that #defined symbol anywhere.

  This is for portability, some system might use long or long long or ...

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

class JStringData {
public:
  size_t  bufferSize;  // Allocated Buffer Size
  size_t  length;      // Length of Data
  long    nbRefs;      // Reference Counter
  int     lock;        // Lock, if direct access (CJString compatibility)
  char*   data;

  /* Kept public for easy access by JString
     A more secure Friend Class definition might do it better. */

////////////////////////////////////////////////////////////////////////////
/// Constructor, Copy Constructor and Destructor                         ///
////////////////////////////////////////////////////////////////////////////
  inline JStringData();
  inline JStringData( const char* s );
  inline JStringData( const char* s, size_t nBuffer );
  inline JStringData( const JStringData& sd );
  inline JStringData( size_t nBuffer );
  inline JStringData( char fill, size_t nRepeat );
  inline JStringData( char fill, size_t nRepeat, size_t nBuffer );
  inline virtual ~JStringData();

////////////////////////////////////////////////////////////////////////////
/// Utility functions                                                    ///
////////////////////////////////////////////////////////////////////////////
  inline void Dec();  // NOTICE: Dec() is a Suicidal function !
  inline void Inc();

  // Might become private...
  void Init( const char* s, size_t nBuffer );
  void InitBuffer( size_t nBuffer, char fill );
  void Clear( char fill );

private:
  // Might become public ?
  const JStringData& operator=(const JStringData& sd);

public:
  // Global Null JStringData Object
  // I hate this, but it's the only optimize way of doing this !
  // I tried without and the testing of pdata == NULL are awful ! 
  static JStringData* strNull()
  {
    static JStringData s;
    return &s;
  }
};

#define strNull  JStringData::strNull()

// Global Null JStringData Object
// I hate this, but it's the only optimize way of doing this !
// I tried without and the testing of pdata == NULL are awful ! 
// JStringData strNull;

/** ANDREA ***************************************************

  You are defining this global variable in an include file.
  This means that every compilation unit using the library
  will have its own strNull object and, if you're lucky,
  the linker will complain.
  Can you handle several different strNull objects lying
  around ?

  That was a problem, that's why String.cpp is included inorder
  else we get many JStringData

  There are several solution for this problem, the simplest
  being using a static member function

       static JStringData *strNull()
       {
         static JStringData s;
         return &s;
       }

  Well, that's an implementation I saw in a String class on Linux,
  in the 1st place, I didn't have that global variable,
  but I had to check for NULL so often that it was too messy.
  With this one, it's much more easier and faster !

  I will probably used "extern" keyword, so it doesn't screw up.

  October 2000:

  I used your trick, it's seems to be a good idea,
  to avoid headache !  Thanks!

  Fred

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

#endif

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