Category : Files from Magazines
Archive   : PCTV3N5.ZIP
Filename : NEWDEBUG.H

/////////////////////////////////////////////////
// DEBUG DYNAMIC MEMORY ALLOCATION
// newdebug.h
//
// Implements a debugging replacement for
// the standard C++ memory allocation
// operators.
//
// Tested with:
// Microsoft C/C++ 7.00
// Borland C++ 3.x
//
// Copyright 1992 Scott Robert Ladd
// All Rights Reserved
/////////////////////////////////////////////////

#ifndef NEWDEBUG_H
#define NEWDEBUG_H

#include "stddef.h"

//-----------------------------------------------
// NewDbg
// This class encapsulates the tools used in
// tracking and verifying dynamic memory
// allocations. "new" and "delete" are
// friends to provide access to the
// protected members of NewDbg.
//-----------------------------------------------

class NewDbg
{
friend void * operator new (size_t size);
friend void operator delete (void * ptr);

public:
// error codes
enum Errors
{
EF_OKAY,
EF_ZEROSIZE,
EF_NOTALLOC,
EF_INVALID,
EF_UNDERFLOW,
EF_TOOMANY
};

// returns number of active allocations
static long GetCount();

// returns number of bytes allocated
static long GetBytes();

// returns non-zero if ptr
// was allocated with new
static int IsDynamic(void * ptr);

// returns the current error code
static Errors GetError();

// sets the error code to EF_OKAY
static void ClearError();

// sets the function called on error
static void InstallHandler(
void (* func)(Errors flag));

// called when an error occurs
static void ReportError(Errors err);

protected:

// header data for tracking allocations
struct AllocHeader
{
unsigned short Marker;
size_t Bytes;
};

// number of items allocated
static long Count;

// number of bytes allocated
static long Bytes;

// current error code
static Errors ErrorFlag;

// allocation marker
static const unsigned short CorrectMark;

// pointer to function called on error
static void (* ErrorFunc)(Errors flag);
};

// pointer to C++ error handler
extern void (* _new_handler)();

// function to set _new_handler
void (* set_new_handler(void (* handler)()))();

// synonym for set_new_handler
#define _set_new_handler(ptr) set_new_handler(ptr)

// debugging implementations of new and delete
void * operator new (size_t size);
void operator delete (void * ptr);

#endif