object.h

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/*
 * object.h
 *
 * Mother of all ancestor classes.
 *
 * Portable Tools Library
 *
 * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
 * All Rights Reserved.
 *
 * Contributor(s): ______________________________________.
 *
 * $Revision: 26129 $
 * $Author: rjongbloed $
 * $Date: 2011-07-07 21:42:50 -0500 (Thu, 07 Jul 2011) $
 */

#ifndef PTLIB_OBJECT_H
#define PTLIB_OBJECT_H

#ifdef P_USE_PRAGMA
#pragma interface
#endif

#if defined(_WIN32) || defined(_WIN32_WCE)
#include "msos/ptlib/contain.h"
#else
#include "unix/ptlib/contain.h"
#endif

#if defined(P_VXWORKS)
#include <private/stdiop.h>
#endif

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>

#include <string.h>

#include <string>
#include <iomanip>
#include <iostream>
#include <sstream>


#define P_REMOVE_VIRTUAL_INTERNAL_BASE(fn) __inline virtual struct ptlib_virtual_function_changed_or_removed ****** fn { return 0; }

#if defined(_MSC_VER)
  #if _MSC_VER < 1310
    #define P_DEPRECATED
    #define P_REMOVE_VIRTUAL_INTERNAL(type, fn, body) P_REMOVE_VIRTUAL_INTERNAL_BASE(fn)
  #elif _MSC_VER < 1400
    #define P_DEPRECATED __declspec(deprecated)
    #define P_REMOVE_VIRTUAL_INTERNAL(type, fn, body) __inline virtual __declspec(deprecated) type fn body
  #else
    #define P_DEPRECATED __declspec(deprecated)
    #define P_REMOVE_VIRTUAL_INTERNAL(type, fn, body) __inline virtual __declspec(deprecated("Virtual function signature changed or function deprecated")) type fn body
  #endif
#elif defined(__GNUC__)
  #if __GNUC__ < 4
    #define P_DEPRECATED
    #define P_REMOVE_VIRTUAL_INTERNAL(type, fn, body) P_REMOVE_VIRTUAL_INTERNAL_BASE(fn)
  #else
    #define P_DEPRECATED __attribute__((deprecated))
    #define P_REMOVE_VIRTUAL_INTERNAL(type, fn, body) __attribute__((warn_unused_result)) __attribute__((deprecated)) P_REMOVE_VIRTUAL_INTERNAL_BASE(fn)
  #endif
#else
    #define P_DEPRECATED
    #define P_REMOVE_VIRTUAL_INTERNAL(type, fn, body) P_REMOVE_VIRTUAL_INTERNAL_BASE(fn)
#endif

#define P_REMOVE_VIRTUAL_VOID(fn)       P_REMOVE_VIRTUAL_INTERNAL(void, fn, {})
#define P_REMOVE_VIRTUAL(type, fn, ret) P_REMOVE_VIRTUAL_INTERNAL(type, fn, { return ret; })


// P_USE_INTEGER_BOOL is the default and gives the old behaviour (it
// is also used for C translation units).
// without P_USE_INTEGER_BOOL, the ANSI C++ bool is used.

#if defined(P_USE_INTEGER_BOOL) || !defined(__cplusplus)
   typedef BOOL PBoolean;
#  define PTrue TRUE
#  define PFalse FALSE
#else
   typedef bool PBoolean;
#  define PTrue true
#  define PFalse false
#endif


// Disable inlines when debugging for faster compiles (the compiler doesn't
// actually inline the function with debug on any way).

#ifndef P_USE_INLINES
#ifdef _DEBUG
#define P_USE_INLINES 0
#else
#define P_USE_INLINES 0
#endif
#endif

#if P_USE_INLINES
#define PINLINE inline
#else
#define PINLINE
#endif


// Declare the debugging support

#ifndef P_USE_ASSERTS
#define P_USE_ASSERTS 1
#endif

#if !P_USE_ASSERTS

#define PAssert(b, m) (b)
#define PAssert2(b, c, m) (b)
#define PAssertOS(b) (b)
#define PAssertNULL(p) (p)
#define PAssertAlways(m) {}
#define PAssertAlways2(c, m) {}

#else // P_USE_ASSERTS

enum PStandardAssertMessage {
  PLogicError,              
  POutOfMemory,             
  PNullPointerReference,    
  PInvalidCast,             
  PInvalidArrayIndex,       
  PInvalidArrayElement,     
  PStackEmpty,              
  PUnimplementedFunction,   
  PInvalidParameter,        
  POperatingSystemError,    
  PChannelNotOpen,          
  PUnsupportedFeature,      
  PInvalidWindow,           
  PMaxStandardAssertMessage 
};

#define __CLASS__ NULL

void PAssertFunc(const char * file, int line, const char * className, PStandardAssertMessage msg);
void PAssertFunc(const char * file, int line, const char * className, const char * msg);
void PAssertFunc(const char * full_msg);

inline bool PAssertFuncInline(bool b, const char * file, int line, const char * className, PStandardAssertMessage msg)
{
  if (!b) 
    PAssertFunc(file, line, className, msg);
  return b;
}
inline bool PAssertFuncInline(bool b, const char * file, int line, const char * className, const char * msg)
{
  if (!b) 
    PAssertFunc(file, line, className, msg);
  return b;
}

#define PAssert(b, msg) PAssertFuncInline((b), __FILE__,__LINE__,__CLASS__,(msg))

#define PAssert2(b, cls, msg) PAssertFuncInline((b), __FILE__,__LINE__,(cls),(msg))

#define PAssertOS(b) PAssertFuncInline((b), __FILE__,__LINE__,__CLASS__,POperatingSystemError)

#define PAssertNULL(ptr) (((ptr)!=NULL)?(ptr): \
                     (PAssertFunc(__FILE__,__LINE__, __CLASS__, PNullPointerReference),(ptr)))

#define PAssertAlways(msg) PAssertFunc(__FILE__,__LINE__,__CLASS__,(msg))

#define PAssertAlways2(cls, msg) PAssertFunc(__FILE__,__LINE__,(cls),(msg))

#endif // P_USE_ASSERTS


ostream & PGetErrorStream();

void PSetErrorStream(ostream * strm  );

#define PError (PGetErrorStream())



// Debug and tracing

#ifndef PTRACING
#define PTRACING 1
#endif

#if PTRACING

class PTrace
{
public:
  enum Options {
    Blocks = 1,
    DateAndTime = 2,
    Timestamp = 4,
    Thread = 8,
    TraceLevel = 16,
    FileAndLine = 32,
    ThreadAddress = 64,
    AppendToFile = 128,
    GMTTime = 256,
    RotateDaily = 512,
    RotateHourly = 1024,
    RotateMinutely = 2048,
    RotateLogMask = RotateDaily + RotateHourly + RotateMinutely,
    SystemLogStream = 32768
  };


  static void Initialise(
    unsigned level,                               
    const char * filename = NULL,                 
    unsigned options = Timestamp | Thread | Blocks 
  );

  static void Initialise(
    unsigned level,                                 
    const char * filename,                          
    const char * rolloverPattern,                   
    unsigned options = Timestamp | Thread | Blocks  
  );

  static void SetOptions(
    unsigned options 
  );

  static void ClearOptions(
    unsigned options 
  );

  static unsigned GetOptions();

  static void SetLevel(
    unsigned level 
  );

  static unsigned GetLevel();

  static PBoolean CanTrace(
    unsigned level 
  );

  static void SetStream(
    ostream * out 
  );

  static ostream & Begin(
    unsigned level,         
    const char * fileName,  
    int lineNum             
  );

  static ostream & End(
    ostream & strm 
  );

  static void Cleanup();

  class Block {
    public:
      Block(
        const char * fileName, 
        int lineNum,           
        const char * traceName
       );
      Block(const Block & obj)
        : file(obj.file), line(obj.line), name(obj.name) { }
      ~Block();
    private:
      Block & operator=(const Block &)
      { return *this; }
      const char * file;
      int          line;
      const char * name;
  };
};

/* Macro to conditionally declare a parameter to a function to avoid compiler
   warning due that parameter only being used in a <code>PTRACE()</code> */
#define PTRACE_PARAM(param) param

#define PTRACE_BLOCK(name) PTrace::Block __trace_block_instance(__FILE__, __LINE__, name)

#define PTRACE_LINE() \
    if (PTrace::CanTrace(1)) \
      PTrace::Begin(1, __FILE__, __LINE__) << __FILE__ << '(' << __LINE__ << ')' << PTrace::End; \
    else (void)0

#define PTRACE(level, args) \
    if (PTrace::CanTrace(level)) \
      PTrace::Begin(level, __FILE__, __LINE__) << args << PTrace::End; \
    else (void)0

#define PTRACE_IF(level, cond, args) \
    if ((PTrace::CanTrace(level) && (cond))) \
      PTrace::Begin(level, __FILE__, __LINE__) << args << PTrace::End; \
    else (void)0

#else // PTRACING

#define PTRACE_PARAM(param)
#define PTRACE_BLOCK(n)
#define PTRACE_LINE()
#define PTRACE(level, arg)
#define PTRACE_IF(level, cond, args)

#endif // PTRACING



#if PMEMORY_CHECK || (defined(_MSC_VER) && defined(_DEBUG) && !defined(_WIN32_WCE)) 

#define PMEMORY_HEAP 1

class PMemoryHeap {
  public:
    PMemoryHeap();

    // Clear up the memory checking subsystem, dumping memory leaks.
    ~PMemoryHeap();

    static void * Allocate(
      size_t nSize,           
      const char * file,      
      int line,               
      const char * className  
    );
    static void * Allocate(
      size_t count,       
      size_t iSize,       
      const char * file,  
      int line            
    );

    static void * Reallocate(
      void * ptr,         
      size_t nSize,       
      const char * file,  
      int line            
    );

    static void Deallocate(
      void * ptr,             
      const char * className  
    );

    enum Validation {
      Ok, Bad, Trashed
    };
    static Validation Validate(
      const void * ptr,       
      const char * className, 
      ostream * error         
    );

    static PBoolean ValidateHeap(
      ostream * error = NULL  
    );

    static PBoolean SetIgnoreAllocations(
      PBoolean ignore  
    );

    static void DumpStatistics();
    static void DumpStatistics(ostream & strm );

#if PMEMORY_CHECK
    struct State {
      DWORD allocationNumber;
    };
#else
        typedef _CrtMemState State;
#endif

    /* Get memory state.
      This returns a state that may be used to determine where to start dumping
      objects from.
     */
    static void GetState(
      State & state  
    );

    static void DumpObjectsSince(
      const State & when    
    );

    static void DumpObjectsSince(
      const State & when,   
      ostream & strm        
    );

    static void SetAllocationBreakpoint(
      DWORD point   
    );

#if PMEMORY_CHECK

  protected:
    void * InternalAllocate(
      size_t nSize,           // Number of bytes to allocate.
      const char * file,      // Source file name for allocating function.
      int line,               // Source file line for allocating function.
      const char * className  // Class name for allocating function.
    );
    Validation InternalValidate(
      const void * ptr,       // Pointer to memory block to check
      const char * className, // Class name it should be.
      ostream * error         // Stream to receive error message (may be NULL)
    );
    void InternalDumpStatistics(ostream & strm);
    void InternalDumpObjectsSince(DWORD objectNumber, ostream & strm);

    class Wrapper {
      public:
        Wrapper();
        ~Wrapper();
        PMemoryHeap * operator->() const { return instance; }
      private:
        PMemoryHeap * instance;
    };
    friend class Wrapper;

    enum Flags {
      NoLeakPrint = 1
    };

#pragma pack(1)
    struct Header {
      enum {
        // Assure that the Header struct is aligned to 8 byte boundary
        NumGuardBytes = 16 - (sizeof(Header *) +
                              sizeof(Header *) +
                              sizeof(const char *) +
                              sizeof(const char *) +
                              sizeof(size_t) +
                              sizeof(DWORD) +
                              sizeof(WORD) +
                              sizeof(BYTE)
#ifdef P_LINUX
                              + sizeof(pthread_t)
#endif
                              )%8
      };

      Header     * prev;
      Header     * next;
      const char * className;
      const char * fileName;
      size_t       size;
      DWORD        request;
      WORD         line;
      BYTE         flags;
#ifdef P_LINUX
      pthread_t    thread;
#endif
      char         guard[NumGuardBytes];

      static char GuardBytes[NumGuardBytes];
    };
#pragma pack()

    PBoolean isDestroyed;

    Header * listHead;
    Header * listTail;

    static DWORD allocationBreakpoint;
    DWORD allocationRequest;
    DWORD firstRealObject;
    BYTE  flags;

    char  allocFillChar;
    char  freeFillChar;

    DWORD currentMemoryUsage;
    DWORD peakMemoryUsage;
    DWORD currentObjects;
    DWORD peakObjects;
    DWORD totalObjects;

    ostream * leakDumpStream;

#if defined(_WIN32)
    CRITICAL_SECTION mutex;
#elif defined(P_PTHREADS)
    pthread_mutex_t mutex;
#elif defined(P_VXWORKS)
    void * mutex;
#endif

#else

#define P_CLIENT_BLOCK (_CLIENT_BLOCK|(0x61<<16)) // This identifies a PObject derived class
    _CrtMemState initialState;

#endif // PMEMORY_CHECK
};


inline void * runtime_malloc(size_t bytes  ) { return malloc(bytes); }

inline void runtime_free(void * ptr  ) { free(ptr); }


#define malloc(s) PMemoryHeap::Allocate(s, __FILE__, __LINE__, NULL)

#define calloc(n,s) PMemoryHeap::Allocate(n, s, __FILE__, __LINE__)

#define realloc(p,s) PMemoryHeap::Reallocate(p, s, __FILE__, __LINE__)


#define free(p) PMemoryHeap::Deallocate(p, NULL)


#define cfree(p) PMemoryHeap::Deallocate(p, NULL)


#define PNEW  new (__FILE__, __LINE__)

#if !defined(_MSC_VER) || _MSC_VER<1200
#define PSPECIAL_DELETE_FUNCTION
#else
#define PSPECIAL_DELETE_FUNCTION \
    void operator delete(void * ptr, const char *, int) \
      { PMemoryHeap::Deallocate(ptr, Class()); } \
    void operator delete[](void * ptr, const char *, int) \
      { PMemoryHeap::Deallocate(ptr, Class()); }
#endif

#define PNEW_AND_DELETE_FUNCTIONS \
    void * operator new(size_t nSize, const char * file, int line) \
      { return PMemoryHeap::Allocate(nSize, file, line, Class()); } \
    void * operator new(size_t nSize) \
      { return PMemoryHeap::Allocate(nSize, NULL, 0, Class()); } \
    void operator delete(void * ptr) \
      { PMemoryHeap::Deallocate(ptr, Class()); } \
    void * operator new(size_t, void * placement) \
      { return placement; } \
    void operator delete(void *, void *) \
      { } \
    void * operator new[](size_t nSize, const char * file, int line) \
      { return PMemoryHeap::Allocate(nSize, file, line, Class()); } \
    void * operator new[](size_t nSize) \
      { return PMemoryHeap::Allocate(nSize, NULL, 0, Class()); } \
    void operator delete[](void * ptr) \
      { PMemoryHeap::Deallocate(ptr, Class()); } \
    PSPECIAL_DELETE_FUNCTION


inline void * operator new(size_t nSize, const char * file, int line)
  { return PMemoryHeap::Allocate(nSize, file, line, NULL); }

inline void * operator new[](size_t nSize, const char * file, int line)
  { return PMemoryHeap::Allocate(nSize, file, line, NULL); }

#ifndef __GNUC__
void * operator new(size_t nSize);
void * operator new[](size_t nSize);

void operator delete(void * ptr);
void operator delete[](void * ptr);

#if defined(_MSC_VER) && _MSC_VER>=1200
inline void operator delete(void * ptr, const char *, int)
  { PMemoryHeap::Deallocate(ptr, NULL); }

inline void operator delete[](void * ptr, const char *, int)
  { PMemoryHeap::Deallocate(ptr, NULL); }
#endif
#endif


class PMemoryHeapIgnoreAllocationsForScope {
public:
  PMemoryHeapIgnoreAllocationsForScope() : previousIgnoreAllocations(PMemoryHeap::SetIgnoreAllocations(true)) { }
  ~PMemoryHeapIgnoreAllocationsForScope() { PMemoryHeap::SetIgnoreAllocations(previousIgnoreAllocations); }
private:
  PBoolean previousIgnoreAllocations;
};

#define PMEMORY_IGNORE_ALLOCATIONS_FOR_SCOPE PMemoryHeapIgnoreAllocationsForScope instance_PMemoryHeapIgnoreAllocationsForScope

class PMemoryAllocationBreakpoint {
public:
  PMemoryAllocationBreakpoint(DWORD point)
  {
    PMemoryHeap::SetAllocationBreakpoint(point);
  }
};

#define PMEMORY_ALLOCATION_BREAKPOINT(point) PMemoryAllocationBreakpoint PMemoryAllocationBreakpointInstance(point)


#else // PMEMORY_CHECK || (defined(_MSC_VER) && defined(_DEBUG))

#define PMEMORY_HEAP 0

#define PNEW new

#define PNEW_AND_DELETE_FUNCTIONS

#define runtime_malloc(s) malloc(s)
#define runtime_free(p) free(p)

#define PMEMORY_IGNORE_ALLOCATIONS_FOR_SCOPE
#define PMEMORY_ALLOCATION_BREAKPOINT(point)

#endif // PMEMORY_CHECK || (defined(_MSC_VER) && defined(_DEBUG))



/*
 *  Implement "construct on first use" paradigm
 */

template <class GnuAllocator, class Type>
struct PAllocatorTemplate
{
  Type * allocate(size_t v)  
  {
    return GetAllocator().allocate(v);
  }

  void deallocate(Type * p, size_t v)  
  {
    GetAllocator().deallocate(p, v);
  }

  private:
    static GnuAllocator & GetAllocator()
    {
      static GnuAllocator instance;
      return instance;
    }
};

#define GCC_VERSION (__GNUC__ * 10000 \
                   + __GNUC_MINOR__ * 100 \
                   + __GNUC_PATCHLEVEL__)

// Memory pooling allocators
#if defined(__GNUC__) && (GCC_VERSION > 40000) && !defined(P_MINGW) && !defined(P_MACOSX) 
#include <ext/mt_allocator.h>
template <class Type> struct PFixedPoolAllocator    : public PAllocatorTemplate<__gnu_cxx::__mt_alloc<Type>, Type> { };
template <class Type> struct PVariablePoolAllocator : public PAllocatorTemplate<__gnu_cxx::__mt_alloc<Type>, Type> { };

#else

template <class Type> struct PFixedPoolAllocator    : public PAllocatorTemplate<std::allocator<Type>, Type> { };
template <class Type> struct PVariablePoolAllocator : public PAllocatorTemplate<std::allocator<Type>, Type> { };
#endif

#define PDECLARE_POOL_ALLOCATOR() \
    void * operator new(size_t nSize); \
    void * operator new(size_t nSize, const char * file, int line); \
    void operator delete(void * ptr); \
    void operator delete(void * ptr, const char *, int)

#define PDEFINE_POOL_ALLOCATOR(cls) \
  static PFixedPoolAllocator<cls> cls##_allocator; \
  void * cls::operator new(size_t)                           { return cls##_allocator.allocate(1);               } \
  void * cls::operator new(size_t, const char *, int)        { return cls##_allocator.allocate(1);               } \
  void   cls::operator delete(void * ptr)                    {        cls##_allocator.deallocate((cls *)ptr, 1); } \
  void   cls::operator delete(void * ptr, const char *, int) {        cls##_allocator.deallocate((cls *)ptr, 1); }


#define PCLASSINFO(cls, par) \
  public: \
    typedef cls P_thisClass; \
    static inline const char * Class() \
      { return #cls; } \
    virtual PBoolean InternalIsDescendant(const char * clsName) const \
      { return strcmp(clsName, cls::Class()) == 0 || par::InternalIsDescendant(clsName); } \
    virtual const char * GetClass(unsigned ancestor = 0) const \
      { return ancestor > 0 ? par::GetClass(ancestor-1) : cls::Class(); } \
    virtual PObject::Comparison CompareObjectMemoryDirect(const PObject & _obj) const \
      { return (PObject::Comparison)memcmp(this, &_obj, sizeof(cls)); } \
    PNEW_AND_DELETE_FUNCTIONS


#if P_HAS_TYPEINFO

#define PIsDescendant(ptr, cls)    (dynamic_cast<const cls *>(ptr) != NULL) 
#define PIsDescendantStr(ptr, str) ((ptr)->InternalIsDescendant(str)) 

#define PRemoveConst(cls, ptr)  (const_cast<cls*>(ptr))

#if P_USE_ASSERTS
template<class BaseClass> inline BaseClass * PAssertCast(BaseClass * obj, const char * file, int line) 
  { if (obj == NULL) PAssertFunc(file, line, BaseClass::Class(), PInvalidCast); return obj; }
#define PDownCast(cls, ptr) PAssertCast<cls>(dynamic_cast<cls*>(ptr),__FILE__,__LINE__)
#else
#define PDownCast(cls, ptr) (dynamic_cast<cls*>(ptr))
#endif

#include <typeinfo>

#else // P_HAS_TYPEINFO

#define PIsDescendant(ptr, cls)    ((ptr)->InternalIsDescendant(cls::Class()))
#define PIsDescendantStr(ptr, str) ((ptr)->InternalIsDescendant(str))

#define PRemoveConst(cls, ptr)  ((cls*)(ptr))

#if P_USE_ASSERTS
template<class BaseClass> inline BaseClass * PAssertCast(PObject * obj, const char * file, int line) 
  { if (obj->InternalIsDescendant(BaseClass::Class())) return (BaseClass *)obj; PAssertFunc(file, line, BaseClass::Class(), PInvalidCast); return NULL; }
#define PDownCast(cls, ptr) PAssertCast<cls>((ptr),__FILE__,__LINE__)
#else
#define PDownCast(cls, ptr) ((cls*)(ptr))
#endif

#endif // P_HAS_TYPEINFO


#define PDECLARE_CLASS(cls, par) class cls : public par { PCLASSINFO(cls, par)
#ifdef DOC_PLUS_PLUS
} Match previous opening brace in doc++
#endif

// The root of all evil ... umm classes

class PObject {

  protected:
    PObject() { }

  public:
    /* Destructor required to get the "virtual". A PObject really has nothing
       to destroy.
     */
    virtual ~PObject() { }

    static inline const char * Class()    { return "PObject"; }

    virtual const char * GetClass(unsigned ancestor = 0) const { return ancestor > 0 ? "" : Class(); }

    PBoolean IsClass(const char * cls) const 
    { return strcmp(cls, GetClass()) == 0; }

    virtual PBoolean InternalIsDescendant(
      const char * clsName    // Ancestor class name to compare against.
    ) const
    { return IsClass(clsName); }


    enum Comparison {
      LessThan = -1,
      EqualTo = 0,
      GreaterThan = 1
    };

    virtual Comparison Compare(
      const PObject & obj   // Object to compare against.
    ) const;
    
    virtual Comparison CompareObjectMemoryDirect(
      const PObject & obj   // Object to compare against.
    ) const;

    bool operator==(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) == EqualTo; }

    bool operator!=(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) != EqualTo; }

    bool operator<(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) == LessThan; }

    bool operator>(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) == GreaterThan; }

    bool operator<=(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) != GreaterThan; }

    bool operator>=(
      const PObject & obj   // Object to compare against.
    ) const { return Compare(obj) != LessThan; }

    virtual void PrintOn(
      ostream &strm   // Stream to print the object into.
    ) const;

    virtual void ReadFrom(
      istream &strm   // Stream to read the objects contents from.
    );


    inline friend ostream & operator<<(
      ostream &strm,       
      const PObject & obj  
    ) { obj.PrintOn(strm); return strm; }

    inline friend istream & operator>>(
      istream &strm,   
      PObject & obj    
    ) { obj.ReadFrom(strm); return strm; }


    virtual PObject * Clone() const;

    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


template <typename type>
struct PIntSameOrder {
  __inline PIntSameOrder()                            : data(0)              { }
  __inline PIntSameOrder(type value)                  : data(value)          { }
  __inline PIntSameOrder(const PIntSameOrder & value) : data(value.data)     { }
  __inline PIntSameOrder & operator=(type value)                             { data = value; return *this; }
  __inline PIntSameOrder & operator=(const PIntSameOrder & value)            { data = value.data; return *this; }
  __inline operator type() const                                             { return data; }
  __inline friend ostream & operator<<(ostream & s, const PIntSameOrder & v) { return s << v.data; }
  __inline friend istream & operator>>(istream & s, PIntSameOrder & v)       { return s >> v.data; }

  private:
    type data;
};


template <typename type>
struct PIntReversedOrder {
  __inline PIntReversedOrder()                                : data(0)              { }
  __inline PIntReversedOrder(type value)                                             { ReverseBytes(value, data); }
  __inline PIntReversedOrder(const PIntReversedOrder & value) : data(value.data)     { }
  __inline PIntReversedOrder & operator=(type value)                                 { ReverseBytes(value, data); return *this; }
  __inline PIntReversedOrder & operator=(const PIntReversedOrder & value)            { data = value.data; return *this; }
  __inline operator type() const                                                     { type value; ReverseBytes(data, value); return value; }
  __inline friend ostream & operator<<(ostream & s, const PIntReversedOrder & value) { return s << (type)value; }
  __inline friend istream & operator>>(istream & s, PIntReversedOrder & v)           { type val; s >> val; v = val; return s; }

  private:
    type data;

  static __inline void ReverseBytes(const type & src, type & dst)
  {
    size_t s = sizeof(type)-1;
    for (size_t d = 0; d < sizeof(type); ++d,--s)
      ((BYTE *)&dst)[d] = ((const BYTE *)&src)[s];
  }
};

#ifndef PCHAR8
#define PCHAR8 PANSI_CHAR
#endif

#if PCHAR8==PANSI_CHAR
typedef PIntSameOrder<char> PChar8;
#endif

typedef PIntSameOrder<char> PInt8;

typedef PIntSameOrder<unsigned char> PUInt8;

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<PInt16> PInt16l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<PInt16> PInt16l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<PInt16> PInt16b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<PInt16> PInt16b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<WORD> PUInt16l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<WORD> PUInt16l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<WORD> PUInt16b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<WORD> PUInt16b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<PInt32> PInt32l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<PInt32> PInt32l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<PInt32> PInt32b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<PInt32> PInt32b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<DWORD> PUInt32l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<DWORD> PUInt32l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<DWORD> PUInt32b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<DWORD> PUInt32b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<PInt64> PInt64l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<PInt64> PInt64l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<PInt64> PInt64b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<PInt64> PInt64b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<PUInt64> PUInt64l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<PUInt64> PUInt64l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<PUInt64> PUInt64b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<PUInt64> PUInt64b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<float> PFloat32l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<float> PFloat32l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<float> PFloat32b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<float> PFloat32b;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<double> PFloat64l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<double> PFloat64l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<double> PFloat64b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<double> PFloat64b;
#endif

#ifndef NO_LONG_DOUBLE // stupid OSX compiler
#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntSameOrder<long double> PFloat80l;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntReversedOrder<long double> PFloat80l;
#endif

#if PBYTE_ORDER==PLITTLE_ENDIAN
typedef PIntReversedOrder<long double> PFloat80b;
#elif PBYTE_ORDER==PBIG_ENDIAN
typedef PIntSameOrder<long double> PFloat80b;
#endif
#endif


// 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 <code>v1</code> or <code>v2</code> 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 <code>v1</code> or <code>v2</code> 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 <code>val</code> is executed twice so extreme care should be
   made in its use.
 */
#define PABS(v) ((v) < 0 ? -(v) : (v))


#endif // PTLIB_OBJECT_H


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