object.h

pwlib源码库

    ) const { return Compare(obj) != EqualTo; }

    /** Compare the two objects.
    
       @return
       TRUE if objects are less than.
     */
    bool operator<(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) == LessThan; }

    /** Compare the two objects.
    
       @return
       TRUE if objects are greater than.
     */
    bool operator>(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) == GreaterThan; }

    /** Compare the two objects.
    
       @return
       TRUE if objects are less than or equal.
     */
    bool operator<=(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) != GreaterThan; }

    /** Compare the two objects.
    
       @return
       TRUE if objects are greater than or equal.
     */
    bool operator>=(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) != LessThan; }
  //@}

  /**@name I/O functions */
  //@{
    /** Output the contents of the object to the stream. The exact output is
       dependent on the exact semantics of the descendent class. This is
       primarily used by the standard #operator<<# function.

       The default behaviour is to print the class name.
     */
    virtual void PrintOn(
      ostream &strm   // Stream to print the object into.
    ) const;

    /** Input the contents of the object from the stream. The exact input is
       dependent on the exact semantics of the descendent class. This is
       primarily used by the standard #operator>># function.

       The default behaviour is to do nothing.
     */
    virtual void ReadFrom(
      istream &strm   // Stream to read the objects contents from.
    );


    /** Global function for using the standard << operator on objects descended
       from PObject. This simply calls the objects #PrintOn()# function.
       
       @return the #strm# parameter.
     */
    inline friend ostream & operator<<(
      ostream &strm,       // Stream to print the object into.
      const PObject & obj  // Object to print to the stream.
    ) { obj.PrintOn(strm); return strm; }

    /** Global function for using the standard >> operator on objects descended
       from PObject. This simply calls the objects #ReadFrom()# function.

       @return the #strm# parameter.
     */
    inline friend istream & operator>>(
      istream &strm,   // Stream to read the objects contents from.
      PObject & obj    // Object to read inormation into.
    ) { obj.ReadFrom(strm); return strm; }


  /**@name Miscellaneous functions */
  //@{
    /** Create a copy of the class on the heap. The exact semantics of the
       descendent class determine what is required to make a duplicate of the
       instance. Not all classes can even {\bf do} a clone operation.
       
       The main user of the clone function is the #PDictionary# class as
       it requires copies of the dictionary keys.

       The default behaviour is for this function to assert.

       @return
       pointer to new copy of the class instance.
     */
    virtual PObject * Clone() const;

    /** This function yields a hash value required by the #PDictionary#
       class. A descendent class that is required to be the key of a dictionary
       should override this function. The precise values returned is dependent
       on the semantics of the class. For example, the #PString# class
       overrides it to provide a hash function for distinguishing text strings.

       The default behaviour is to return the value zero.

       @return
       hash function value for class instance.
     */
    virtual PINDEX HashFunction() const;
  //@}
};

///////////////////////////////////////////////////////////////////////////////
// Platform independent types

// All these classes encapsulate primitive types such that they may be
// transfered in a platform independent manner. In particular it is used to
// do byte swapping for little endien and big endien processor architectures
// as well as accommodating structure packing rules for memory structures.

#define PANSI_CHAR 1
#define PLITTLE_ENDIAN 2
#define PBIG_ENDIAN 3


#if 0
class PStandardType
/* Encapsulate a standard 8 bit character into a portable format. This would
   rarely need to do translation, only if the target platform uses EBCDIC
   would it do anything.

   The platform independent form here is always 8 bit ANSI.
 */
{
  public:
    PStandardType(
      type newVal   // Value to initialise data in platform dependent form.
    ) { data = newVal; }
    /* Create a new instance of the platform independent type using platform
       dependent data, or platform independent streams.
     */

    operator type() { return data; }
    /* Get the platform dependent value for the type.

       @return
       data for instance.
     */

    friend ostream & operator<<(ostream & strm, const PStandardType & val)
      { return strm << (type)val; }
    /* Output the platform dependent value for the type to the stream.

       @return
       the stream output was made to.
     */

    friend istream & operator>>(istream & strm, PStandardType & val)
      { type data; strm >> data; val = PStandardType(data); return strm; }
    /* Input the platform dependent value for the type from the stream.

       @return
       the stream input was made from.
     */


  private:
    type data;
};
#endif


#define PI_SAME(name, type) \
  struct name { \
    name() { } \
    name(type value) { data = value; } \
    name(const name & value) { data = value.data; } \
    name & operator =(type value) { data = value; return *this; } \
    name & operator =(const name & value) { data = value.data; return *this; } \
    operator type() const { return data; } \
    friend ostream & operator<<(ostream & s, const name & v) { return s << v.data; } \
    friend istream & operator>>(istream & s, name & v) { return s >> v.data; } \
    private: type data; \
  }

#define PI_LOOP(src, dst) \
    BYTE *s = ((BYTE *)&src)+sizeof(src); BYTE *d = (BYTE *)&dst; \
    while (s != (BYTE *)&src) *d++ = *--s;

#define PI_DIFF(name, type) \
  struct name { \
    name() { } \
    name(type value) { operator=(value); } \
    name(const name & value) { data = value.data; } \
    name & operator =(type value) { PI_LOOP(value, data); return *this; } \
    name & operator =(const name & value) { data = value.data; return *this; } \
    operator type() const { type value; PI_LOOP(data, value); return value; } \
    friend ostream & operator<<(ostream & s, const name & value) { return s << (type)value; } \
    friend istream & operator>>(istream & s, name & v) { type val; s >> val; v = val; return s; } \
    private: type data; \
  }

#ifndef PCHAR8
#define PCHAR8 PANSI_CHAR
#endif

#if PCHAR8==PANSI_CHAR
PI_SAME(PChar8, char);
#endif

PI_SAME(PInt8, signed char);

PI_SAME(PUInt8, unsigned char);

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PInt16l, PInt16);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PInt16l, PInt16);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PInt16b, PInt16);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PInt16b, PInt16);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PUInt16l, WORD);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PUInt16l, WORD);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PUInt16b, WORD);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PUInt16b, WORD);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PInt32l, PInt32);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PInt32l, PInt32);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PInt32b, PInt32);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PInt32b, PInt32);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PUInt32l, DWORD);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PUInt32l, DWORD);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PUInt32b, DWORD);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PUInt32b, DWORD);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PInt64l, PInt64);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PInt64l, PInt64);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PInt64b, PInt64);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PInt64b, PInt64);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PUInt64l, PUInt64);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PUInt64l, PUInt64);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PUInt64b, PUInt64);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PUInt64b, PUInt64);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PFloat32l, float);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PFloat32l, float);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PFloat32b, float);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PFloat32b, float);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PFloat64l, double);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PFloat64l, double);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PFloat64b, double);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PFloat64b, double);
#endif

#ifndef NO_LONG_DOUBLE // stupid OSX compiler
#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_SAME(PFloat80l, long double);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_DIFF(PFloat80l, long double);
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
PI_DIFF(PFloat80b, long double);
#elif PBYTE_ORDER==PBIG_ENDIAN
PI_SAME(PFloat80b, long double);
#endif
#endif

#undef PI_LOOP
#undef PI_SAME
#undef PI_DIFF


///////////////////////////////////////////////////////////////////////////////
// Miscellaneous

/*$MACRO PARRAYSIZE(array)
   This macro is used to calculate the number of array elements in a static
   array.
 */
#define PARRAYSIZE(array) ((PINDEX)(sizeof(array)/sizeof(array[0])))

/*$MACRO PMIN(v1, v2)
   This macro is used to calculate the minimum of two values. As this is a
   macro the expression in #v1# or #v2# is executed
   twice so extreme care should be made in its use.
 */
#define PMIN(v1, v2) ((v1) < (v2) ? (v1) : (v2))

/*$MACRO PMAX(v1, v2)
   This macro is used to calculate the maximum of two values. As this is a
   macro the expression in #v1# or #v2# is executed
   twice so extreme care should be made in its use.
 */
#define PMAX(v1, v2) ((v1) > (v2) ? (v1) : (v2))

/*$MACRO PABS(val)
   This macro is used to calculate an absolute value. As this is a macro the
   expression in #val# is executed twice so extreme care should be
   made in its use.
 */
#define PABS(v) ((v) < 0 ? -(v) : (v))

#endif // _POBJECT_H

// End Of File ///////////////////////////////////////////////////////////////